drivers/usb/host/fotg210-hcd.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /* Faraday FOTG210 EHCI-like driver
   3  *
   4  * Copyright (c) 2013 Faraday Technology Corporation
   5  *
   6  * Author: Yuan-Hsin Chen <yhchen@faraday-tech.com>
   7  *         Feng-Hsin Chiang <john453@faraday-tech.com>
   8  *         Po-Yu Chuang <ratbert.chuang@gmail.com>
   9  *
  10  * Most of code borrowed from the Linux-3.7 EHCI driver
  11  */
  12 #include <linux/module.h>
  13 #include <linux/of.h>
  14 #include <linux/device.h>
  15 #include <linux/dmapool.h>
  16 #include <linux/kernel.h>
  17 #include <linux/delay.h>
  18 #include <linux/ioport.h>
  19 #include <linux/sched.h>
  20 #include <linux/vmalloc.h>
  21 #include <linux/errno.h>
  22 #include <linux/init.h>
  23 #include <linux/hrtimer.h>
  24 #include <linux/list.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/usb.h>
  27 #include <linux/usb/hcd.h>
  28 #include <linux/moduleparam.h>
  29 #include <linux/dma-mapping.h>
  30 #include <linux/debugfs.h>
  31 #include <linux/slab.h>
  32 #include <linux/uaccess.h>
  33 #include <linux/platform_device.h>
  34 #include <linux/io.h>
  35 #include <linux/iopoll.h>
  36 #include <linux/clk.h>
  37
  38 #include <asm/byteorder.h>
  39 #include <asm/irq.h>
  40 #include <asm/unaligned.h>
  41
  42 #define DRIVER_AUTHOR "Yuan-Hsin Chen"
  43 #define DRIVER_DESC "FOTG210 Host Controller (EHCI) Driver"
  44 static const char hcd_name[] = "fotg210_hcd";
  45
  46 #undef FOTG210_URB_TRACE
  47 #define FOTG210_STATS
  48
  49 /* magic numbers that can affect system performance */
  50 #define FOTG210_TUNE_CERR       3 /* 0-3 qtd retries; 0 == don't stop */
  51 #define FOTG210_TUNE_RL_HS      4 /* nak throttle; see 4.9 */
  52 #define FOTG210_TUNE_RL_TT      0
  53 #define FOTG210_TUNE_MULT_HS    1 /* 1-3 transactions/uframe; 4.10.3 */
  54 #define FOTG210_TUNE_MULT_TT    1
  55
  56 /* Some drivers think it's safe to schedule isochronous transfers more than 256
  57  * ms into the future (partly as a result of an old bug in the scheduling
  58  * code).  In an attempt to avoid trouble, we will use a minimum scheduling
  59  * length of 512 frames instead of 256.
  60  */
  61 #define FOTG210_TUNE_FLS 1 /* (medium) 512-frame schedule */
  62
  63 /* Initial IRQ latency:  faster than hw default */
  64 static int log2_irq_thresh; /* 0 to 6 */
  65 module_param(log2_irq_thresh, int, S_IRUGO);
  66 MODULE_PARM_DESC(log2_irq_thresh, "log2 IRQ latency, 1-64 microframes");
  67
  68 /* initial park setting:  slower than hw default */
  69 static unsigned park;
  70 module_param(park, uint, S_IRUGO);
  71 MODULE_PARM_DESC(park, "park setting; 1-3 back-to-back async packets");
  72
  73 /* for link power management(LPM) feature */
  74 static unsigned int hird;
  75 module_param(hird, int, S_IRUGO);
  76 MODULE_PARM_DESC(hird, "host initiated resume duration, +1 for each 75us");
  77
  78 #define INTR_MASK (STS_IAA | STS_FATAL | STS_PCD | STS_ERR | STS_INT)
  79
  80 #include "fotg210.h"
  81
  82 #define fotg210_dbg(fotg210, fmt, args...) \
  83         dev_dbg(fotg210_to_hcd(fotg210)->self.controller, fmt, ## args)
  84 #define fotg210_err(fotg210, fmt, args...) \
  85         dev_err(fotg210_to_hcd(fotg210)->self.controller, fmt, ## args)
  86 #define fotg210_info(fotg210, fmt, args...) \
  87         dev_info(fotg210_to_hcd(fotg210)->self.controller, fmt, ## args)
  88 #define fotg210_warn(fotg210, fmt, args...) \
  89         dev_warn(fotg210_to_hcd(fotg210)->self.controller, fmt, ## args)
  90
  91 /* check the values in the HCSPARAMS register (host controller _Structural_
  92  * parameters) see EHCI spec, Table 2-4 for each value
  93  */
  94 static void dbg_hcs_params(struct fotg210_hcd *fotg210, char *label)
  95 {
  96         u32 params = fotg210_readl(fotg210, &fotg210->caps->hcs_params);
  97
  98         fotg210_dbg(fotg210, "%s hcs_params 0x%x ports=%d\n", label, params,
  99                         HCS_N_PORTS(params));
 100 }
 101
 102 /* check the values in the HCCPARAMS register (host controller _Capability_
 103  * parameters) see EHCI Spec, Table 2-5 for each value
 104  */
 105 static void dbg_hcc_params(struct fotg210_hcd *fotg210, char *label)
 106 {
 107         u32 params = fotg210_readl(fotg210, &fotg210->caps->hcc_params);
 108
 109         fotg210_dbg(fotg210, "%s hcc_params %04x uframes %s%s\n", label,
 110                         params,
 111                         HCC_PGM_FRAMELISTLEN(params) ? "256/512/1024" : "1024",
 112                         HCC_CANPARK(params) ? " park" : "");
 113 }
 114
 115 static void __maybe_unused
 116 dbg_qtd(const char *label, struct fotg210_hcd *fotg210, struct fotg210_qtd *qtd)
 117 {
 118         fotg210_dbg(fotg210, "%s td %p n%08x %08x t%08x p0=%08x\n", label, qtd,
 119                         hc32_to_cpup(fotg210, &qtd->hw_next),
 120                         hc32_to_cpup(fotg210, &qtd->hw_alt_next),
 121                         hc32_to_cpup(fotg210, &qtd->hw_token),
 122                         hc32_to_cpup(fotg210, &qtd->hw_buf[0]));
 123         if (qtd->hw_buf[1])
 124                 fotg210_dbg(fotg210, "  p1=%08x p2=%08x p3=%08x p4=%08x\n",
 125                                 hc32_to_cpup(fotg210, &qtd->hw_buf[1]),
 126                                 hc32_to_cpup(fotg210, &qtd->hw_buf[2]),
 127                                 hc32_to_cpup(fotg210, &qtd->hw_buf[3]),
 128                                 hc32_to_cpup(fotg210, &qtd->hw_buf[4]));
 129 }
 130
 131 static void __maybe_unused
 132 dbg_qh(const char *label, struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
 133 {
 134         struct fotg210_qh_hw *hw = qh->hw;
 135
 136         fotg210_dbg(fotg210, "%s qh %p n%08x info %x %x qtd %x\n", label, qh,
 137                         hw->hw_next, hw->hw_info1, hw->hw_info2,
 138                         hw->hw_current);
 139
 140         dbg_qtd("overlay", fotg210, (struct fotg210_qtd *) &hw->hw_qtd_next);
 141 }
 142
 143 static void __maybe_unused
 144 dbg_itd(const char *label, struct fotg210_hcd *fotg210, struct fotg210_itd *itd)
 145 {
 146         fotg210_dbg(fotg210, "%s[%d] itd %p, next %08x, urb %p\n", label,
 147                         itd->frame, itd, hc32_to_cpu(fotg210, itd->hw_next),
 148                         itd->urb);
 149
 150         fotg210_dbg(fotg210,
 151                         "  trans: %08x %08x %08x %08x %08x %08x %08x %08x\n",
 152                         hc32_to_cpu(fotg210, itd->hw_transaction[0]),
 153                         hc32_to_cpu(fotg210, itd->hw_transaction[1]),
 154                         hc32_to_cpu(fotg210, itd->hw_transaction[2]),
 155                         hc32_to_cpu(fotg210, itd->hw_transaction[3]),
 156                         hc32_to_cpu(fotg210, itd->hw_transaction[4]),
 157                         hc32_to_cpu(fotg210, itd->hw_transaction[5]),
 158                         hc32_to_cpu(fotg210, itd->hw_transaction[6]),
 159                         hc32_to_cpu(fotg210, itd->hw_transaction[7]));
 160
 161         fotg210_dbg(fotg210,
 162                         "  buf:   %08x %08x %08x %08x %08x %08x %08x\n",
 163                         hc32_to_cpu(fotg210, itd->hw_bufp[0]),
 164                         hc32_to_cpu(fotg210, itd->hw_bufp[1]),
 165                         hc32_to_cpu(fotg210, itd->hw_bufp[2]),
 166                         hc32_to_cpu(fotg210, itd->hw_bufp[3]),
 167                         hc32_to_cpu(fotg210, itd->hw_bufp[4]),
 168                         hc32_to_cpu(fotg210, itd->hw_bufp[5]),
 169                         hc32_to_cpu(fotg210, itd->hw_bufp[6]));
 170
 171         fotg210_dbg(fotg210, "  index: %d %d %d %d %d %d %d %d\n",
 172                         itd->index[0], itd->index[1], itd->index[2],
 173                         itd->index[3], itd->index[4], itd->index[5],
 174                         itd->index[6], itd->index[7]);
 175 }
 176
 177 static int __maybe_unused
 178 dbg_status_buf(char *buf, unsigned len, const char *label, u32 status)
 179 {
 180         return scnprintf(buf, len, "%s%sstatus %04x%s%s%s%s%s%s%s%s%s%s",
 181                         label, label[0] ? " " : "", status,
 182                         (status & STS_ASS) ? " Async" : "",
 183                         (status & STS_PSS) ? " Periodic" : "",
 184                         (status & STS_RECL) ? " Recl" : "",
 185                         (status & STS_HALT) ? " Halt" : "",
 186                         (status & STS_IAA) ? " IAA" : "",
 187                         (status & STS_FATAL) ? " FATAL" : "",
 188                         (status & STS_FLR) ? " FLR" : "",
 189                         (status & STS_PCD) ? " PCD" : "",
 190                         (status & STS_ERR) ? " ERR" : "",
 191                         (status & STS_INT) ? " INT" : "");
 192 }
 193
 194 static int __maybe_unused
 195 dbg_intr_buf(char *buf, unsigned len, const char *label, u32 enable)
 196 {
 197         return scnprintf(buf, len, "%s%sintrenable %02x%s%s%s%s%s%s",
 198                         label, label[0] ? " " : "", enable,
 199                         (enable & STS_IAA) ? " IAA" : "",
 200                         (enable & STS_FATAL) ? " FATAL" : "",
 201                         (enable & STS_FLR) ? " FLR" : "",
 202                         (enable & STS_PCD) ? " PCD" : "",
 203                         (enable & STS_ERR) ? " ERR" : "",
 204                         (enable & STS_INT) ? " INT" : "");
 205 }
 206
 207 static const char *const fls_strings[] = { "1024", "512", "256", "??" };
 208
 209 static int dbg_command_buf(char *buf, unsigned len, const char *label,
 210                 u32 command)
 211 {
 212         return scnprintf(buf, len,
 213                         "%s%scommand %07x %s=%d ithresh=%d%s%s%s period=%s%s %s",
 214                         label, label[0] ? " " : "", command,
 215                         (command & CMD_PARK) ? " park" : "(park)",
 216                         CMD_PARK_CNT(command),
 217                         (command >> 16) & 0x3f,
 218                         (command & CMD_IAAD) ? " IAAD" : "",
 219                         (command & CMD_ASE) ? " Async" : "",
 220                         (command & CMD_PSE) ? " Periodic" : "",
 221                         fls_strings[(command >> 2) & 0x3],
 222                         (command & CMD_RESET) ? " Reset" : "",
 223                         (command & CMD_RUN) ? "RUN" : "HALT");
 224 }
 225
 226 static char *dbg_port_buf(char *buf, unsigned len, const char *label, int port,
 227                 u32 status)
 228 {
 229         char *sig;
 230
 231         /* signaling state */
 232         switch (status & (3 << 10)) {
 233         case 0 << 10:
 234                 sig = "se0";
 235                 break;
 236         case 1 << 10:
 237                 sig = "k";
 238                 break; /* low speed */
 239         case 2 << 10:
 240                 sig = "j";
 241                 break;
 242         default:
 243                 sig = "?";
 244                 break;
 245         }
 246
 247         scnprintf(buf, len, "%s%sport:%d status %06x %d sig=%s%s%s%s%s%s%s%s",
 248                         label, label[0] ? " " : "", port, status,
 249                         status >> 25, /*device address */
 250                         sig,
 251                         (status & PORT_RESET) ? " RESET" : "",
 252                         (status & PORT_SUSPEND) ? " SUSPEND" : "",
 253                         (status & PORT_RESUME) ? " RESUME" : "",
 254                         (status & PORT_PEC) ? " PEC" : "",
 255                         (status & PORT_PE) ? " PE" : "",
 256                         (status & PORT_CSC) ? " CSC" : "",
 257                         (status & PORT_CONNECT) ? " CONNECT" : "");
 258
 259         return buf;
 260 }
 261
 262 /* functions have the "wrong" filename when they're output... */
 263 #define dbg_status(fotg210, label, status) {                    \
 264         char _buf[80];                                          \
 265         dbg_status_buf(_buf, sizeof(_buf), label, status);      \
 266         fotg210_dbg(fotg210, "%s\n", _buf);                     \
 267 }
 268
 269 #define dbg_cmd(fotg210, label, command) {                      \
 270         char _buf[80];                                          \
 271         dbg_command_buf(_buf, sizeof(_buf), label, command);    \
 272         fotg210_dbg(fotg210, "%s\n", _buf);                     \
 273 }
 274
 275 #define dbg_port(fotg210, label, port, status) {                               \
 276         char _buf[80];                                                         \
 277         fotg210_dbg(fotg210, "%s\n",                                           \
 278                         dbg_port_buf(_buf, sizeof(_buf), label, port, status));\
 279 }
 280
 281 /* troubleshooting help: expose state in debugfs */
 282 static int debug_async_open(struct inode *, struct file *);
 283 static int debug_periodic_open(struct inode *, struct file *);
 284 static int debug_registers_open(struct inode *, struct file *);
 285 static int debug_async_open(struct inode *, struct file *);
 286
 287 static ssize_t debug_output(struct file*, char __user*, size_t, loff_t*);
 288 static int debug_close(struct inode *, struct file *);
 289
 290 static const struct file_operations debug_async_fops = {
 291         .owner          = THIS_MODULE,
 292         .open           = debug_async_open,
 293         .read           = debug_output,
 294         .release        = debug_close,
 295         .llseek         = default_llseek,
 296 };
 297 static const struct file_operations debug_periodic_fops = {
 298         .owner          = THIS_MODULE,
 299         .open           = debug_periodic_open,
 300         .read           = debug_output,
 301         .release        = debug_close,
 302         .llseek         = default_llseek,
 303 };
 304 static const struct file_operations debug_registers_fops = {
 305         .owner          = THIS_MODULE,
 306         .open           = debug_registers_open,
 307         .read           = debug_output,
 308         .release        = debug_close,
 309         .llseek         = default_llseek,
 310 };
 311
 312 static struct dentry *fotg210_debug_root;
 313
 314 struct debug_buffer {
 315         ssize_t (*fill_func)(struct debug_buffer *);    /* fill method */
 316         struct usb_bus *bus;
 317         struct mutex mutex;     /* protect filling of buffer */
 318         size_t count;           /* number of characters filled into buffer */
 319         char *output_buf;
 320         size_t alloc_size;
 321 };
 322
 323 static inline char speed_char(u32 scratch)
 324 {
 325         switch (scratch & (3 << 12)) {
 326         case QH_FULL_SPEED:
 327                 return 'f';
 328
 329         case QH_LOW_SPEED:
 330                 return 'l';
 331
 332         case QH_HIGH_SPEED:
 333                 return 'h';
 334
 335         default:
 336                 return '?';
 337         }
 338 }
 339
 340 static inline char token_mark(struct fotg210_hcd *fotg210, __hc32 token)
 341 {
 342         __u32 v = hc32_to_cpu(fotg210, token);
 343
 344         if (v & QTD_STS_ACTIVE)
 345                 return '*';
 346         if (v & QTD_STS_HALT)
 347                 return '-';
 348         if (!IS_SHORT_READ(v))
 349                 return ' ';
 350         /* tries to advance through hw_alt_next */
 351         return '/';
 352 }
 353
 354 static void qh_lines(struct fotg210_hcd *fotg210, struct fotg210_qh *qh,
 355                 char **nextp, unsigned *sizep)
 356 {
 357         u32 scratch;
 358         u32 hw_curr;
 359         struct fotg210_qtd *td;
 360         unsigned temp;
 361         unsigned size = *sizep;
 362         char *next = *nextp;
 363         char mark;
 364         __le32 list_end = FOTG210_LIST_END(fotg210);
 365         struct fotg210_qh_hw *hw = qh->hw;
 366
 367         if (hw->hw_qtd_next == list_end) /* NEC does this */
 368                 mark = '@';
 369         else
 370                 mark = token_mark(fotg210, hw->hw_token);
 371         if (mark == '/') { /* qh_alt_next controls qh advance? */
 372                 if ((hw->hw_alt_next & QTD_MASK(fotg210)) ==
 373                     fotg210->async->hw->hw_alt_next)
 374                         mark = '#'; /* blocked */
 375                 else if (hw->hw_alt_next == list_end)
 376                         mark = '.'; /* use hw_qtd_next */
 377                 /* else alt_next points to some other qtd */
 378         }
 379         scratch = hc32_to_cpup(fotg210, &hw->hw_info1);
 380         hw_curr = (mark == '*') ? hc32_to_cpup(fotg210, &hw->hw_current) : 0;
 381         temp = scnprintf(next, size,
 382                         "qh/%p dev%d %cs ep%d %08x %08x(%08x%c %s nak%d)",
 383                         qh, scratch & 0x007f,
 384                         speed_char(scratch),
 385                         (scratch >> 8) & 0x000f,
 386                         scratch, hc32_to_cpup(fotg210, &hw->hw_info2),
 387                         hc32_to_cpup(fotg210, &hw->hw_token), mark,
 388                         (cpu_to_hc32(fotg210, QTD_TOGGLE) & hw->hw_token)
 389                                 ? "data1" : "data0",
 390                         (hc32_to_cpup(fotg210, &hw->hw_alt_next) >> 1) & 0x0f);
 391         size -= temp;
 392         next += temp;
 393
 394         /* hc may be modifying the list as we read it ... */
 395         list_for_each_entry(td, &qh->qtd_list, qtd_list) {
 396                 scratch = hc32_to_cpup(fotg210, &td->hw_token);
 397                 mark = ' ';
 398                 if (hw_curr == td->qtd_dma)
 399                         mark = '*';
 400                 else if (hw->hw_qtd_next == cpu_to_hc32(fotg210, td->qtd_dma))
 401                         mark = '+';
 402                 else if (QTD_LENGTH(scratch)) {
 403                         if (td->hw_alt_next == fotg210->async->hw->hw_alt_next)
 404                                 mark = '#';
 405                         else if (td->hw_alt_next != list_end)
 406                                 mark = '/';
 407                 }
 408                 temp = snprintf(next, size,
 409                                 "\n\t%p%c%s len=%d %08x urb %p",
 410                                 td, mark, ({ char *tmp;
 411                                 switch ((scratch>>8)&0x03) {
 412                                 case 0:
 413                                         tmp = "out";
 414                                         break;
 415                                 case 1:
 416                                         tmp = "in";
 417                                         break;
 418                                 case 2:
 419                                         tmp = "setup";
 420                                         break;
 421                                 default:
 422                                         tmp = "?";
 423                                         break;
 424                                  } tmp; }),
 425                                 (scratch >> 16) & 0x7fff,
 426                                 scratch,
 427                                 td->urb);
 428                 if (size < temp)
 429                         temp = size;
 430                 size -= temp;
 431                 next += temp;
 432                 if (temp == size)
 433                         goto done;
 434         }
 435
 436         temp = snprintf(next, size, "\n");
 437         if (size < temp)
 438                 temp = size;
 439
 440         size -= temp;
 441         next += temp;
 442
 443 done:
 444         *sizep = size;
 445         *nextp = next;
 446 }
 447
 448 static ssize_t fill_async_buffer(struct debug_buffer *buf)
 449 {
 450         struct usb_hcd *hcd;
 451         struct fotg210_hcd *fotg210;
 452         unsigned long flags;
 453         unsigned temp, size;
 454         char *next;
 455         struct fotg210_qh *qh;
 456
 457         hcd = bus_to_hcd(buf->bus);
 458         fotg210 = hcd_to_fotg210(hcd);
 459         next = buf->output_buf;
 460         size = buf->alloc_size;
 461
 462         *next = 0;
 463
 464         /* dumps a snapshot of the async schedule.
 465          * usually empty except for long-term bulk reads, or head.
 466          * one QH per line, and TDs we know about
 467          */
 468         spin_lock_irqsave(&fotg210->lock, flags);
 469         for (qh = fotg210->async->qh_next.qh; size > 0 && qh;
 470                         qh = qh->qh_next.qh)
 471                 qh_lines(fotg210, qh, &next, &size);
 472         if (fotg210->async_unlink && size > 0) {
 473                 temp = scnprintf(next, size, "\nunlink =\n");
 474                 size -= temp;
 475                 next += temp;
 476
 477                 for (qh = fotg210->async_unlink; size > 0 && qh;
 478                                 qh = qh->unlink_next)
 479                         qh_lines(fotg210, qh, &next, &size);
 480         }
 481         spin_unlock_irqrestore(&fotg210->lock, flags);
 482
 483         return strlen(buf->output_buf);
 484 }
 485
 486 /* count tds, get ep direction */
 487 static unsigned output_buf_tds_dir(char *buf, struct fotg210_hcd *fotg210,
 488                 struct fotg210_qh_hw *hw, struct fotg210_qh *qh, unsigned size)
 489 {
 490         u32 scratch = hc32_to_cpup(fotg210, &hw->hw_info1);
 491         struct fotg210_qtd *qtd;
 492         char *type = "";
 493         unsigned temp = 0;
 494
 495         /* count tds, get ep direction */
 496         list_for_each_entry(qtd, &qh->qtd_list, qtd_list) {
 497                 temp++;
 498                 switch ((hc32_to_cpu(fotg210, qtd->hw_token) >> 8) & 0x03) {
 499                 case 0:
 500                         type = "out";
 501                         continue;
 502                 case 1:
 503                         type = "in";
 504                         continue;
 505                 }
 506         }
 507
 508         return scnprintf(buf, size, "(%c%d ep%d%s [%d/%d] q%d p%d)",
 509                         speed_char(scratch), scratch & 0x007f,
 510                         (scratch >> 8) & 0x000f, type, qh->usecs,
 511                         qh->c_usecs, temp, (scratch >> 16) & 0x7ff);
 512 }
 513
 514 #define DBG_SCHED_LIMIT 64
 515 static ssize_t fill_periodic_buffer(struct debug_buffer *buf)
 516 {
 517         struct usb_hcd *hcd;
 518         struct fotg210_hcd *fotg210;
 519         unsigned long flags;
 520         union fotg210_shadow p, *seen;
 521         unsigned temp, size, seen_count;
 522         char *next;
 523         unsigned i;
 524         __hc32 tag;
 525
 526         seen = kmalloc_array(DBG_SCHED_LIMIT, sizeof(*seen), GFP_ATOMIC);
 527         if (!seen)
 528                 return 0;
 529
 530         seen_count = 0;
 531
 532         hcd = bus_to_hcd(buf->bus);
 533         fotg210 = hcd_to_fotg210(hcd);
 534         next = buf->output_buf;
 535         size = buf->alloc_size;
 536
 537         temp = scnprintf(next, size, "size = %d\n", fotg210->periodic_size);
 538         size -= temp;
 539         next += temp;
 540
 541         /* dump a snapshot of the periodic schedule.
 542          * iso changes, interrupt usually doesn't.
 543          */
 544         spin_lock_irqsave(&fotg210->lock, flags);
 545         for (i = 0; i < fotg210->periodic_size; i++) {
 546                 p = fotg210->pshadow[i];
 547                 if (likely(!p.ptr))
 548                         continue;
 549
 550                 tag = Q_NEXT_TYPE(fotg210, fotg210->periodic[i]);
 551
 552                 temp = scnprintf(next, size, "%4d: ", i);
 553                 size -= temp;
 554                 next += temp;
 555
 556                 do {
 557                         struct fotg210_qh_hw *hw;
 558
 559                         switch (hc32_to_cpu(fotg210, tag)) {
 560                         case Q_TYPE_QH:
 561                                 hw = p.qh->hw;
 562                                 temp = scnprintf(next, size, " qh%d-%04x/%p",
 563                                                 p.qh->period,
 564                                                 hc32_to_cpup(fotg210,
 565                                                         &hw->hw_info2)
 566                                                         /* uframe masks */
 567                                                         & (QH_CMASK | QH_SMASK),
 568                                                 p.qh);
 569                                 size -= temp;
 570                                 next += temp;
 571                                 /* don't repeat what follows this qh */
 572                                 for (temp = 0; temp < seen_count; temp++) {
 573                                         if (seen[temp].ptr != p.ptr)
 574                                                 continue;
 575                                         if (p.qh->qh_next.ptr) {
 576                                                 temp = scnprintf(next, size,
 577                                                                 " ...");
 578                                                 size -= temp;
 579                                                 next += temp;
 580                                         }
 581                                         break;
 582                                 }
 583                                 /* show more info the first time around */
 584                                 if (temp == seen_count) {
 585                                         temp = output_buf_tds_dir(next,
 586                                                         fotg210, hw,
 587                                                         p.qh, size);
 588
 589                                         if (seen_count < DBG_SCHED_LIMIT)
 590                                                 seen[seen_count++].qh = p.qh;
 591                                 } else
 592                                         temp = 0;
 593                                 tag = Q_NEXT_TYPE(fotg210, hw->hw_next);
 594                                 p = p.qh->qh_next;
 595                                 break;
 596                         case Q_TYPE_FSTN:
 597                                 temp = scnprintf(next, size,
 598                                                 " fstn-%8x/%p",
 599                                                 p.fstn->hw_prev, p.fstn);
 600                                 tag = Q_NEXT_TYPE(fotg210, p.fstn->hw_next);
 601                                 p = p.fstn->fstn_next;
 602                                 break;
 603                         case Q_TYPE_ITD:
 604                                 temp = scnprintf(next, size,
 605                                                 " itd/%p", p.itd);
 606                                 tag = Q_NEXT_TYPE(fotg210, p.itd->hw_next);
 607                                 p = p.itd->itd_next;
 608                                 break;
 609                         }
 610                         size -= temp;
 611                         next += temp;
 612                 } while (p.ptr);
 613
 614                 temp = scnprintf(next, size, "\n");
 615                 size -= temp;
 616                 next += temp;
 617         }
 618         spin_unlock_irqrestore(&fotg210->lock, flags);
 619         kfree(seen);
 620
 621         return buf->alloc_size - size;
 622 }
 623 #undef DBG_SCHED_LIMIT
 624
 625 static const char *rh_state_string(struct fotg210_hcd *fotg210)
 626 {
 627         switch (fotg210->rh_state) {
 628         case FOTG210_RH_HALTED:
 629                 return "halted";
 630         case FOTG210_RH_SUSPENDED:
 631                 return "suspended";
 632         case FOTG210_RH_RUNNING:
 633                 return "running";
 634         case FOTG210_RH_STOPPING:
 635                 return "stopping";
 636         }
 637         return "?";
 638 }
 639
 640 static ssize_t fill_registers_buffer(struct debug_buffer *buf)
 641 {
 642         struct usb_hcd *hcd;
 643         struct fotg210_hcd *fotg210;
 644         unsigned long flags;
 645         unsigned temp, size, i;
 646         char *next, scratch[80];
 647         static const char fmt[] = "%*s\n";
 648         static const char label[] = "";
 649
 650         hcd = bus_to_hcd(buf->bus);
 651         fotg210 = hcd_to_fotg210(hcd);
 652         next = buf->output_buf;
 653         size = buf->alloc_size;
 654
 655         spin_lock_irqsave(&fotg210->lock, flags);
 656
 657         if (!HCD_HW_ACCESSIBLE(hcd)) {
 658                 size = scnprintf(next, size,
 659                                 "bus %s, device %s\n"
 660                                 "%s\n"
 661                                 "SUSPENDED(no register access)\n",
 662                                 hcd->self.controller->bus->name,
 663                                 dev_name(hcd->self.controller),
 664                                 hcd->product_desc);
 665                 goto done;
 666         }
 667
 668         /* Capability Registers */
 669         i = HC_VERSION(fotg210, fotg210_readl(fotg210,
 670                         &fotg210->caps->hc_capbase));
 671         temp = scnprintf(next, size,
 672                         "bus %s, device %s\n"
 673                         "%s\n"
 674                         "EHCI %x.%02x, rh state %s\n",
 675                         hcd->self.controller->bus->name,
 676                         dev_name(hcd->self.controller),
 677                         hcd->product_desc,
 678                         i >> 8, i & 0x0ff, rh_state_string(fotg210));
 679         size -= temp;
 680         next += temp;
 681
 682         /* FIXME interpret both types of params */
 683         i = fotg210_readl(fotg210, &fotg210->caps->hcs_params);
 684         temp = scnprintf(next, size, "structural params 0x%08x\n", i);
 685         size -= temp;
 686         next += temp;
 687
 688         i = fotg210_readl(fotg210, &fotg210->caps->hcc_params);
 689         temp = scnprintf(next, size, "capability params 0x%08x\n", i);
 690         size -= temp;
 691         next += temp;
 692
 693         /* Operational Registers */
 694         temp = dbg_status_buf(scratch, sizeof(scratch), label,
 695                         fotg210_readl(fotg210, &fotg210->regs->status));
 696         temp = scnprintf(next, size, fmt, temp, scratch);
 697         size -= temp;
 698         next += temp;
 699
 700         temp = dbg_command_buf(scratch, sizeof(scratch), label,
 701                         fotg210_readl(fotg210, &fotg210->regs->command));
 702         temp = scnprintf(next, size, fmt, temp, scratch);
 703         size -= temp;
 704         next += temp;
 705
 706         temp = dbg_intr_buf(scratch, sizeof(scratch), label,
 707                         fotg210_readl(fotg210, &fotg210->regs->intr_enable));
 708         temp = scnprintf(next, size, fmt, temp, scratch);
 709         size -= temp;
 710         next += temp;
 711
 712         temp = scnprintf(next, size, "uframe %04x\n",
 713                         fotg210_read_frame_index(fotg210));
 714         size -= temp;
 715         next += temp;
 716
 717         if (fotg210->async_unlink) {
 718                 temp = scnprintf(next, size, "async unlink qh %p\n",
 719                                 fotg210->async_unlink);
 720                 size -= temp;
 721                 next += temp;
 722         }
 723
 724 #ifdef FOTG210_STATS
 725         temp = scnprintf(next, size,
 726                         "irq normal %ld err %ld iaa %ld(lost %ld)\n",
 727                         fotg210->stats.normal, fotg210->stats.error,
 728                         fotg210->stats.iaa, fotg210->stats.lost_iaa);
 729         size -= temp;
 730         next += temp;
 731
 732         temp = scnprintf(next, size, "complete %ld unlink %ld\n",
 733                         fotg210->stats.complete, fotg210->stats.unlink);
 734         size -= temp;
 735         next += temp;
 736 #endif
 737
 738 done:
 739         spin_unlock_irqrestore(&fotg210->lock, flags);
 740
 741         return buf->alloc_size - size;
 742 }
 743
 744 static struct debug_buffer
 745 *alloc_buffer(struct usb_bus *bus, ssize_t (*fill_func)(struct debug_buffer *))
 746 {
 747         struct debug_buffer *buf;
 748
 749         buf = kzalloc(sizeof(struct debug_buffer), GFP_KERNEL);
 750
 751         if (buf) {
 752                 buf->bus = bus;
 753                 buf->fill_func = fill_func;
 754                 mutex_init(&buf->mutex);
 755                 buf->alloc_size = PAGE_SIZE;
 756         }
 757
 758         return buf;
 759 }
 760
 761 static int fill_buffer(struct debug_buffer *buf)
 762 {
 763         int ret = 0;
 764
 765         if (!buf->output_buf)
 766                 buf->output_buf = vmalloc(buf->alloc_size);
 767
 768         if (!buf->output_buf) {
 769                 ret = -ENOMEM;
 770                 goto out;
 771         }
 772
 773         ret = buf->fill_func(buf);
 774
 775         if (ret >= 0) {
 776                 buf->count = ret;
 777                 ret = 0;
 778         }
 779
 780 out:
 781         return ret;
 782 }
 783
 784 static ssize_t debug_output(struct file *file, char __user *user_buf,
 785                 size_t len, loff_t *offset)
 786 {
 787         struct debug_buffer *buf = file->private_data;
 788         int ret = 0;
 789
 790         mutex_lock(&buf->mutex);
 791         if (buf->count == 0) {
 792                 ret = fill_buffer(buf);
 793                 if (ret != 0) {
 794                         mutex_unlock(&buf->mutex);
 795                         goto out;
 796                 }
 797         }
 798         mutex_unlock(&buf->mutex);
 799
 800         ret = simple_read_from_buffer(user_buf, len, offset,
 801                         buf->output_buf, buf->count);
 802
 803 out:
 804         return ret;
 805
 806 }
 807
 808 static int debug_close(struct inode *inode, struct file *file)
 809 {
 810         struct debug_buffer *buf = file->private_data;
 811
 812         if (buf) {
 813                 vfree(buf->output_buf);
 814                 kfree(buf);
 815         }
 816
 817         return 0;
 818 }
 819 static int debug_async_open(struct inode *inode, struct file *file)
 820 {
 821         file->private_data = alloc_buffer(inode->i_private, fill_async_buffer);
 822
 823         return file->private_data ? 0 : -ENOMEM;
 824 }
 825
 826 static int debug_periodic_open(struct inode *inode, struct file *file)
 827 {
 828         struct debug_buffer *buf;
 829
 830         buf = alloc_buffer(inode->i_private, fill_periodic_buffer);
 831         if (!buf)
 832                 return -ENOMEM;
 833
 834         buf->alloc_size = (sizeof(void *) == 4 ? 6 : 8)*PAGE_SIZE;
 835         file->private_data = buf;
 836         return 0;
 837 }
 838
 839 static int debug_registers_open(struct inode *inode, struct file *file)
 840 {
 841         file->private_data = alloc_buffer(inode->i_private,
 842                         fill_registers_buffer);
 843
 844         return file->private_data ? 0 : -ENOMEM;
 845 }
 846
 847 static inline void create_debug_files(struct fotg210_hcd *fotg210)
 848 {
 849         struct usb_bus *bus = &fotg210_to_hcd(fotg210)->self;
 850         struct dentry *root;
 851
 852         root = debugfs_create_dir(bus->bus_name, fotg210_debug_root);
 853
 854         debugfs_create_file("async", S_IRUGO, root, bus, &debug_async_fops);
 855         debugfs_create_file("periodic", S_IRUGO, root, bus,
 856                             &debug_periodic_fops);
 857         debugfs_create_file("registers", S_IRUGO, root, bus,
 858                             &debug_registers_fops);
 859 }
 860
 861 static inline void remove_debug_files(struct fotg210_hcd *fotg210)
 862 {
 863         struct usb_bus *bus = &fotg210_to_hcd(fotg210)->self;
 864
 865         debugfs_remove(debugfs_lookup(bus->bus_name, fotg210_debug_root));
 866 }
 867
 868 /* handshake - spin reading hc until handshake completes or fails
 869  * @ptr: address of hc register to be read
 870  * @mask: bits to look at in result of read
 871  * @done: value of those bits when handshake succeeds
 872  * @usec: timeout in microseconds
 873  *
 874  * Returns negative errno, or zero on success
 875  *
 876  * Success happens when the "mask" bits have the specified value (hardware
 877  * handshake done).  There are two failure modes:  "usec" have passed (major
 878  * hardware flakeout), or the register reads as all-ones (hardware removed).
 879  *
 880  * That last failure should_only happen in cases like physical cardbus eject
 881  * before driver shutdown. But it also seems to be caused by bugs in cardbus
 882  * bridge shutdown:  shutting down the bridge before the devices using it.
 883  */
 884 static int handshake(struct fotg210_hcd *fotg210, void __iomem *ptr,
 885                 u32 mask, u32 done, int usec)
 886 {
 887         u32 result;
 888         int ret;
 889
 890         ret = readl_poll_timeout_atomic(ptr, result,
 891                                         ((result & mask) == done ||
 892                                          result == U32_MAX), 1, usec);
 893         if (result == U32_MAX)          /* card removed */
 894                 return -ENODEV;
 895
 896         return ret;
 897 }
 898
 899 /* Force HC to halt state from unknown (EHCI spec section 2.3).
 900  * Must be called with interrupts enabled and the lock not held.
 901  */
 902 static int fotg210_halt(struct fotg210_hcd *fotg210)
 903 {
 904         u32 temp;
 905
 906         spin_lock_irq(&fotg210->lock);
 907
 908         /* disable any irqs left enabled by previous code */
 909         fotg210_writel(fotg210, 0, &fotg210->regs->intr_enable);
 910
 911         /*
 912          * This routine gets called during probe before fotg210->command
 913          * has been initialized, so we can't rely on its value.
 914          */
 915         fotg210->command &= ~CMD_RUN;
 916         temp = fotg210_readl(fotg210, &fotg210->regs->command);
 917         temp &= ~(CMD_RUN | CMD_IAAD);
 918         fotg210_writel(fotg210, temp, &fotg210->regs->command);
 919
 920         spin_unlock_irq(&fotg210->lock);
 921         synchronize_irq(fotg210_to_hcd(fotg210)->irq);
 922
 923         return handshake(fotg210, &fotg210->regs->status,
 924                         STS_HALT, STS_HALT, 16 * 125);
 925 }
 926
 927 /* Reset a non-running (STS_HALT == 1) controller.
 928  * Must be called with interrupts enabled and the lock not held.
 929  */
 930 static int fotg210_reset(struct fotg210_hcd *fotg210)
 931 {
 932         int retval;
 933         u32 command = fotg210_readl(fotg210, &fotg210->regs->command);
 934
 935         /* If the EHCI debug controller is active, special care must be
 936          * taken before and after a host controller reset
 937          */
 938         if (fotg210->debug && !dbgp_reset_prep(fotg210_to_hcd(fotg210)))
 939                 fotg210->debug = NULL;
 940
 941         command |= CMD_RESET;
 942         dbg_cmd(fotg210, "reset", command);
 943         fotg210_writel(fotg210, command, &fotg210->regs->command);
 944         fotg210->rh_state = FOTG210_RH_HALTED;
 945         fotg210->next_statechange = jiffies;
 946         retval = handshake(fotg210, &fotg210->regs->command,
 947                         CMD_RESET, 0, 250 * 1000);
 948
 949         if (retval)
 950                 return retval;
 951
 952         if (fotg210->debug)
 953                 dbgp_external_startup(fotg210_to_hcd(fotg210));
 954
 955         fotg210->port_c_suspend = fotg210->suspended_ports =
 956                         fotg210->resuming_ports = 0;
 957         return retval;
 958 }
 959
 960 /* Idle the controller (turn off the schedules).
 961  * Must be called with interrupts enabled and the lock not held.
 962  */
 963 static void fotg210_quiesce(struct fotg210_hcd *fotg210)
 964 {
 965         u32 temp;
 966
 967         if (fotg210->rh_state != FOTG210_RH_RUNNING)
 968                 return;
 969
 970         /* wait for any schedule enables/disables to take effect */
 971         temp = (fotg210->command << 10) & (STS_ASS | STS_PSS);
 972         handshake(fotg210, &fotg210->regs->status, STS_ASS | STS_PSS, temp,
 973                         16 * 125);
 974
 975         /* then disable anything that's still active */
 976         spin_lock_irq(&fotg210->lock);
 977         fotg210->command &= ~(CMD_ASE | CMD_PSE);
 978         fotg210_writel(fotg210, fotg210->command, &fotg210->regs->command);
 979         spin_unlock_irq(&fotg210->lock);
 980
 981         /* hardware can take 16 microframes to turn off ... */
 982         handshake(fotg210, &fotg210->regs->status, STS_ASS | STS_PSS, 0,
 983                         16 * 125);
 984 }
 985
 986 static void end_unlink_async(struct fotg210_hcd *fotg210);
 987 static void unlink_empty_async(struct fotg210_hcd *fotg210);
 988 static void fotg210_work(struct fotg210_hcd *fotg210);
 989 static void start_unlink_intr(struct fotg210_hcd *fotg210,
 990                               struct fotg210_qh *qh);
 991 static void end_unlink_intr(struct fotg210_hcd *fotg210, struct fotg210_qh *qh);
 992
 993 /* Set a bit in the USBCMD register */
 994 static void fotg210_set_command_bit(struct fotg210_hcd *fotg210, u32 bit)
 995 {
 996         fotg210->command |= bit;
 997         fotg210_writel(fotg210, fotg210->command, &fotg210->regs->command);
 998
 999         /* unblock posted write */
1000         fotg210_readl(fotg210, &fotg210->regs->command);
1001 }
1002
1003 /* Clear a bit in the USBCMD register */
1004 static void fotg210_clear_command_bit(struct fotg210_hcd *fotg210, u32 bit)
1005 {
1006         fotg210->command &= ~bit;
1007         fotg210_writel(fotg210, fotg210->command, &fotg210->regs->command);
1008
1009         /* unblock posted write */
1010         fotg210_readl(fotg210, &fotg210->regs->command);
1011 }
1012
1013 /* EHCI timer support...  Now using hrtimers.
1014  *
1015  * Lots of different events are triggered from fotg210->hrtimer.  Whenever
1016  * the timer routine runs, it checks each possible event; events that are
1017  * currently enabled and whose expiration time has passed get handled.
1018  * The set of enabled events is stored as a collection of bitflags in
1019  * fotg210->enabled_hrtimer_events, and they are numbered in order of
1020  * increasing delay values (ranging between 1 ms and 100 ms).
1021  *
1022  * Rather than implementing a sorted list or tree of all pending events,
1023  * we keep track only of the lowest-numbered pending event, in
1024  * fotg210->next_hrtimer_event.  Whenever fotg210->hrtimer gets restarted, its
1025  * expiration time is set to the timeout value for this event.
1026  *
1027  * As a result, events might not get handled right away; the actual delay
1028  * could be anywhere up to twice the requested delay.  This doesn't
1029  * matter, because none of the events are especially time-critical.  The
1030  * ones that matter most all have a delay of 1 ms, so they will be
1031  * handled after 2 ms at most, which is okay.  In addition to this, we
1032  * allow for an expiration range of 1 ms.
1033  */
1034
1035 /* Delay lengths for the hrtimer event types.
1036  * Keep this list sorted by delay length, in the same order as
1037  * the event types indexed by enum fotg210_hrtimer_event in fotg210.h.
1038  */
1039 static unsigned event_delays_ns[] = {
1040         1 * NSEC_PER_MSEC,      /* FOTG210_HRTIMER_POLL_ASS */
1041         1 * NSEC_PER_MSEC,      /* FOTG210_HRTIMER_POLL_PSS */
1042         1 * NSEC_PER_MSEC,      /* FOTG210_HRTIMER_POLL_DEAD */
1043         1125 * NSEC_PER_USEC,   /* FOTG210_HRTIMER_UNLINK_INTR */
1044         2 * NSEC_PER_MSEC,      /* FOTG210_HRTIMER_FREE_ITDS */
1045         6 * NSEC_PER_MSEC,      /* FOTG210_HRTIMER_ASYNC_UNLINKS */
1046         10 * NSEC_PER_MSEC,     /* FOTG210_HRTIMER_IAA_WATCHDOG */
1047         10 * NSEC_PER_MSEC,     /* FOTG210_HRTIMER_DISABLE_PERIODIC */
1048         15 * NSEC_PER_MSEC,     /* FOTG210_HRTIMER_DISABLE_ASYNC */
1049         100 * NSEC_PER_MSEC,    /* FOTG210_HRTIMER_IO_WATCHDOG */
1050 };
1051
1052 /* Enable a pending hrtimer event */
1053 static void fotg210_enable_event(struct fotg210_hcd *fotg210, unsigned event,
1054                 bool resched)
1055 {
1056         ktime_t *timeout = &fotg210->hr_timeouts[event];
1057
1058         if (resched)
1059                 *timeout = ktime_add(ktime_get(), event_delays_ns[event]);
1060         fotg210->enabled_hrtimer_events |= (1 << event);
1061
1062         /* Track only the lowest-numbered pending event */
1063         if (event < fotg210->next_hrtimer_event) {
1064                 fotg210->next_hrtimer_event = event;
1065                 hrtimer_start_range_ns(&fotg210->hrtimer, *timeout,
1066                                 NSEC_PER_MSEC, HRTIMER_MODE_ABS);
1067         }
1068 }
1069
1070
1071 /* Poll the STS_ASS status bit; see when it agrees with CMD_ASE */
1072 static void fotg210_poll_ASS(struct fotg210_hcd *fotg210)
1073 {
1074         unsigned actual, want;
1075
1076         /* Don't enable anything if the controller isn't running (e.g., died) */
1077         if (fotg210->rh_state != FOTG210_RH_RUNNING)
1078                 return;
1079
1080         want = (fotg210->command & CMD_ASE) ? STS_ASS : 0;
1081         actual = fotg210_readl(fotg210, &fotg210->regs->status) & STS_ASS;
1082
1083         if (want != actual) {
1084
1085                 /* Poll again later, but give up after about 20 ms */
1086                 if (fotg210->ASS_poll_count++ < 20) {
1087                         fotg210_enable_event(fotg210, FOTG210_HRTIMER_POLL_ASS,
1088                                         true);
1089                         return;
1090                 }
1091                 fotg210_dbg(fotg210, "Waited too long for the async schedule status (%x/%x), giving up\n",
1092                                 want, actual);
1093         }
1094         fotg210->ASS_poll_count = 0;
1095
1096         /* The status is up-to-date; restart or stop the schedule as needed */
1097         if (want == 0) {        /* Stopped */
1098                 if (fotg210->async_count > 0)
1099                         fotg210_set_command_bit(fotg210, CMD_ASE);
1100
1101         } else {                /* Running */
1102                 if (fotg210->async_count == 0) {
1103
1104                         /* Turn off the schedule after a while */
1105                         fotg210_enable_event(fotg210,
1106                                         FOTG210_HRTIMER_DISABLE_ASYNC,
1107                                         true);
1108                 }
1109         }
1110 }
1111
1112 /* Turn off the async schedule after a brief delay */
1113 static void fotg210_disable_ASE(struct fotg210_hcd *fotg210)
1114 {
1115         fotg210_clear_command_bit(fotg210, CMD_ASE);
1116 }
1117
1118
1119 /* Poll the STS_PSS status bit; see when it agrees with CMD_PSE */
1120 static void fotg210_poll_PSS(struct fotg210_hcd *fotg210)
1121 {
1122         unsigned actual, want;
1123
1124         /* Don't do anything if the controller isn't running (e.g., died) */
1125         if (fotg210->rh_state != FOTG210_RH_RUNNING)
1126                 return;
1127
1128         want = (fotg210->command & CMD_PSE) ? STS_PSS : 0;
1129         actual = fotg210_readl(fotg210, &fotg210->regs->status) & STS_PSS;
1130
1131         if (want != actual) {
1132
1133                 /* Poll again later, but give up after about 20 ms */
1134                 if (fotg210->PSS_poll_count++ < 20) {
1135                         fotg210_enable_event(fotg210, FOTG210_HRTIMER_POLL_PSS,
1136                                         true);
1137                         return;
1138                 }
1139                 fotg210_dbg(fotg210, "Waited too long for the periodic schedule status (%x/%x), giving up\n",
1140                                 want, actual);
1141         }
1142         fotg210->PSS_poll_count = 0;
1143
1144         /* The status is up-to-date; restart or stop the schedule as needed */
1145         if (want == 0) {        /* Stopped */
1146                 if (fotg210->periodic_count > 0)
1147                         fotg210_set_command_bit(fotg210, CMD_PSE);
1148
1149         } else {                /* Running */
1150                 if (fotg210->periodic_count == 0) {
1151
1152                         /* Turn off the schedule after a while */
1153                         fotg210_enable_event(fotg210,
1154                                         FOTG210_HRTIMER_DISABLE_PERIODIC,
1155                                         true);
1156                 }
1157         }
1158 }
1159
1160 /* Turn off the periodic schedule after a brief delay */
1161 static void fotg210_disable_PSE(struct fotg210_hcd *fotg210)
1162 {
1163         fotg210_clear_command_bit(fotg210, CMD_PSE);
1164 }
1165
1166
1167 /* Poll the STS_HALT status bit; see when a dead controller stops */
1168 static void fotg210_handle_controller_death(struct fotg210_hcd *fotg210)
1169 {
1170         if (!(fotg210_readl(fotg210, &fotg210->regs->status) & STS_HALT)) {
1171
1172                 /* Give up after a few milliseconds */
1173                 if (fotg210->died_poll_count++ < 5) {
1174                         /* Try again later */
1175                         fotg210_enable_event(fotg210,
1176                                         FOTG210_HRTIMER_POLL_DEAD, true);
1177                         return;
1178                 }
1179                 fotg210_warn(fotg210, "Waited too long for the controller to stop, giving up\n");
1180         }
1181
1182         /* Clean up the mess */
1183         fotg210->rh_state = FOTG210_RH_HALTED;
1184         fotg210_writel(fotg210, 0, &fotg210->regs->intr_enable);
1185         fotg210_work(fotg210);
1186         end_unlink_async(fotg210);
1187
1188         /* Not in process context, so don't try to reset the controller */
1189 }
1190
1191
1192 /* Handle unlinked interrupt QHs once they are gone from the hardware */
1193 static void fotg210_handle_intr_unlinks(struct fotg210_hcd *fotg210)
1194 {
1195         bool stopped = (fotg210->rh_state < FOTG210_RH_RUNNING);
1196
1197         /*
1198          * Process all the QHs on the intr_unlink list that were added
1199          * before the current unlink cycle began.  The list is in
1200          * temporal order, so stop when we reach the first entry in the
1201          * current cycle.  But if the root hub isn't running then
1202          * process all the QHs on the list.
1203          */
1204         fotg210->intr_unlinking = true;
1205         while (fotg210->intr_unlink) {
1206                 struct fotg210_qh *qh = fotg210->intr_unlink;
1207
1208                 if (!stopped && qh->unlink_cycle == fotg210->intr_unlink_cycle)
1209                         break;
1210                 fotg210->intr_unlink = qh->unlink_next;
1211                 qh->unlink_next = NULL;
1212                 end_unlink_intr(fotg210, qh);
1213         }
1214
1215         /* Handle remaining entries later */
1216         if (fotg210->intr_unlink) {
1217                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_UNLINK_INTR,
1218                                 true);
1219                 ++fotg210->intr_unlink_cycle;
1220         }
1221         fotg210->intr_unlinking = false;
1222 }
1223
1224
1225 /* Start another free-iTDs/siTDs cycle */
1226 static void start_free_itds(struct fotg210_hcd *fotg210)
1227 {
1228         if (!(fotg210->enabled_hrtimer_events &
1229                         BIT(FOTG210_HRTIMER_FREE_ITDS))) {
1230                 fotg210->last_itd_to_free = list_entry(
1231                                 fotg210->cached_itd_list.prev,
1232                                 struct fotg210_itd, itd_list);
1233                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_FREE_ITDS, true);
1234         }
1235 }
1236
1237 /* Wait for controller to stop using old iTDs and siTDs */
1238 static void end_free_itds(struct fotg210_hcd *fotg210)
1239 {
1240         struct fotg210_itd *itd, *n;
1241
1242         if (fotg210->rh_state < FOTG210_RH_RUNNING)
1243                 fotg210->last_itd_to_free = NULL;
1244
1245         list_for_each_entry_safe(itd, n, &fotg210->cached_itd_list, itd_list) {
1246                 list_del(&itd->itd_list);
1247                 dma_pool_free(fotg210->itd_pool, itd, itd->itd_dma);
1248                 if (itd == fotg210->last_itd_to_free)
1249                         break;
1250         }
1251
1252         if (!list_empty(&fotg210->cached_itd_list))
1253                 start_free_itds(fotg210);
1254 }
1255
1256
1257 /* Handle lost (or very late) IAA interrupts */
1258 static void fotg210_iaa_watchdog(struct fotg210_hcd *fotg210)
1259 {
1260         if (fotg210->rh_state != FOTG210_RH_RUNNING)
1261                 return;
1262
1263         /*
1264          * Lost IAA irqs wedge things badly; seen first with a vt8235.
1265          * So we need this watchdog, but must protect it against both
1266          * (a) SMP races against real IAA firing and retriggering, and
1267          * (b) clean HC shutdown, when IAA watchdog was pending.
1268          */
1269         if (fotg210->async_iaa) {
1270                 u32 cmd, status;
1271
1272                 /* If we get here, IAA is *REALLY* late.  It's barely
1273                  * conceivable that the system is so busy that CMD_IAAD
1274                  * is still legitimately set, so let's be sure it's
1275                  * clear before we read STS_IAA.  (The HC should clear
1276                  * CMD_IAAD when it sets STS_IAA.)
1277                  */
1278                 cmd = fotg210_readl(fotg210, &fotg210->regs->command);
1279
1280                 /*
1281                  * If IAA is set here it either legitimately triggered
1282                  * after the watchdog timer expired (_way_ late, so we'll
1283                  * still count it as lost) ... or a silicon erratum:
1284                  * - VIA seems to set IAA without triggering the IRQ;
1285                  * - IAAD potentially cleared without setting IAA.
1286                  */
1287                 status = fotg210_readl(fotg210, &fotg210->regs->status);
1288                 if ((status & STS_IAA) || !(cmd & CMD_IAAD)) {
1289                         INCR(fotg210->stats.lost_iaa);
1290                         fotg210_writel(fotg210, STS_IAA,
1291                                         &fotg210->regs->status);
1292                 }
1293
1294                 fotg210_dbg(fotg210, "IAA watchdog: status %x cmd %x\n",
1295                                 status, cmd);
1296                 end_unlink_async(fotg210);
1297         }
1298 }
1299
1300
1301 /* Enable the I/O watchdog, if appropriate */
1302 static void turn_on_io_watchdog(struct fotg210_hcd *fotg210)
1303 {
1304         /* Not needed if the controller isn't running or it's already enabled */
1305         if (fotg210->rh_state != FOTG210_RH_RUNNING ||
1306                         (fotg210->enabled_hrtimer_events &
1307                         BIT(FOTG210_HRTIMER_IO_WATCHDOG)))
1308                 return;
1309
1310         /*
1311          * Isochronous transfers always need the watchdog.
1312          * For other sorts we use it only if the flag is set.
1313          */
1314         if (fotg210->isoc_count > 0 || (fotg210->need_io_watchdog &&
1315                         fotg210->async_count + fotg210->intr_count > 0))
1316                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_IO_WATCHDOG,
1317                                 true);
1318 }
1319
1320
1321 /* Handler functions for the hrtimer event types.
1322  * Keep this array in the same order as the event types indexed by
1323  * enum fotg210_hrtimer_event in fotg210.h.
1324  */
1325 static void (*event_handlers[])(struct fotg210_hcd *) = {
1326         fotg210_poll_ASS,                       /* FOTG210_HRTIMER_POLL_ASS */
1327         fotg210_poll_PSS,                       /* FOTG210_HRTIMER_POLL_PSS */
1328         fotg210_handle_controller_death,        /* FOTG210_HRTIMER_POLL_DEAD */
1329         fotg210_handle_intr_unlinks,    /* FOTG210_HRTIMER_UNLINK_INTR */
1330         end_free_itds,                  /* FOTG210_HRTIMER_FREE_ITDS */
1331         unlink_empty_async,             /* FOTG210_HRTIMER_ASYNC_UNLINKS */
1332         fotg210_iaa_watchdog,           /* FOTG210_HRTIMER_IAA_WATCHDOG */
1333         fotg210_disable_PSE,            /* FOTG210_HRTIMER_DISABLE_PERIODIC */
1334         fotg210_disable_ASE,            /* FOTG210_HRTIMER_DISABLE_ASYNC */
1335         fotg210_work,                   /* FOTG210_HRTIMER_IO_WATCHDOG */
1336 };
1337
1338 static enum hrtimer_restart fotg210_hrtimer_func(struct hrtimer *t)
1339 {
1340         struct fotg210_hcd *fotg210 =
1341                         container_of(t, struct fotg210_hcd, hrtimer);
1342         ktime_t now;
1343         unsigned long events;
1344         unsigned long flags;
1345         unsigned e;
1346
1347         spin_lock_irqsave(&fotg210->lock, flags);
1348
1349         events = fotg210->enabled_hrtimer_events;
1350         fotg210->enabled_hrtimer_events = 0;
1351         fotg210->next_hrtimer_event = FOTG210_HRTIMER_NO_EVENT;
1352
1353         /*
1354          * Check each pending event.  If its time has expired, handle
1355          * the event; otherwise re-enable it.
1356          */
1357         now = ktime_get();
1358         for_each_set_bit(e, &events, FOTG210_HRTIMER_NUM_EVENTS) {
1359                 if (ktime_compare(now, fotg210->hr_timeouts[e]) >= 0)
1360                         event_handlers[e](fotg210);
1361                 else
1362                         fotg210_enable_event(fotg210, e, false);
1363         }
1364
1365         spin_unlock_irqrestore(&fotg210->lock, flags);
1366         return HRTIMER_NORESTART;
1367 }
1368
1369 #define fotg210_bus_suspend NULL
1370 #define fotg210_bus_resume NULL
1371
1372 static int check_reset_complete(struct fotg210_hcd *fotg210, int index,
1373                 u32 __iomem *status_reg, int port_status)
1374 {
1375         if (!(port_status & PORT_CONNECT))
1376                 return port_status;
1377
1378         /* if reset finished and it's still not enabled -- handoff */
1379         if (!(port_status & PORT_PE))
1380                 /* with integrated TT, there's nobody to hand it to! */
1381                 fotg210_dbg(fotg210, "Failed to enable port %d on root hub TT\n",
1382                                 index + 1);
1383         else
1384                 fotg210_dbg(fotg210, "port %d reset complete, port enabled\n",
1385                                 index + 1);
1386
1387         return port_status;
1388 }
1389
1390
1391 /* build "status change" packet (one or two bytes) from HC registers */
1392
1393 static int fotg210_hub_status_data(struct usb_hcd *hcd, char *buf)
1394 {
1395         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
1396         u32 temp, status;
1397         u32 mask;
1398         int retval = 1;
1399         unsigned long flags;
1400
1401         /* init status to no-changes */
1402         buf[0] = 0;
1403
1404         /* Inform the core about resumes-in-progress by returning
1405          * a non-zero value even if there are no status changes.
1406          */
1407         status = fotg210->resuming_ports;
1408
1409         mask = PORT_CSC | PORT_PEC;
1410         /* PORT_RESUME from hardware ~= PORT_STAT_C_SUSPEND */
1411
1412         /* no hub change reports (bit 0) for now (power, ...) */
1413
1414         /* port N changes (bit N)? */
1415         spin_lock_irqsave(&fotg210->lock, flags);
1416
1417         temp = fotg210_readl(fotg210, &fotg210->regs->port_status);
1418
1419         /*
1420          * Return status information even for ports with OWNER set.
1421          * Otherwise hub_wq wouldn't see the disconnect event when a
1422          * high-speed device is switched over to the companion
1423          * controller by the user.
1424          */
1425
1426         if ((temp & mask) != 0 || test_bit(0, &fotg210->port_c_suspend) ||
1427                         (fotg210->reset_done[0] &&
1428                         time_after_eq(jiffies, fotg210->reset_done[0]))) {
1429                 buf[0] |= 1 << 1;
1430                 status = STS_PCD;
1431         }
1432         /* FIXME autosuspend idle root hubs */
1433         spin_unlock_irqrestore(&fotg210->lock, flags);
1434         return status ? retval : 0;
1435 }
1436
1437 static void fotg210_hub_descriptor(struct fotg210_hcd *fotg210,
1438                 struct usb_hub_descriptor *desc)
1439 {
1440         int ports = HCS_N_PORTS(fotg210->hcs_params);
1441         u16 temp;
1442
1443         desc->bDescriptorType = USB_DT_HUB;
1444         desc->bPwrOn2PwrGood = 10;      /* fotg210 1.0, 2.3.9 says 20ms max */
1445         desc->bHubContrCurrent = 0;
1446
1447         desc->bNbrPorts = ports;
1448         temp = 1 + (ports / 8);
1449         desc->bDescLength = 7 + 2 * temp;
1450
1451         /* two bitmaps:  ports removable, and usb 1.0 legacy PortPwrCtrlMask */
1452         memset(&desc->u.hs.DeviceRemovable[0], 0, temp);
1453         memset(&desc->u.hs.DeviceRemovable[temp], 0xff, temp);
1454
1455         temp = HUB_CHAR_INDV_PORT_OCPM; /* per-port overcurrent reporting */
1456         temp |= HUB_CHAR_NO_LPSM;       /* no power switching */
1457         desc->wHubCharacteristics = cpu_to_le16(temp);
1458 }
1459
1460 static int fotg210_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
1461                 u16 wIndex, char *buf, u16 wLength)
1462 {
1463         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
1464         int ports = HCS_N_PORTS(fotg210->hcs_params);
1465         u32 __iomem *status_reg = &fotg210->regs->port_status;
1466         u32 temp, temp1, status;
1467         unsigned long flags;
1468         int retval = 0;
1469         unsigned selector;
1470
1471         /*
1472          * FIXME:  support SetPortFeatures USB_PORT_FEAT_INDICATOR.
1473          * HCS_INDICATOR may say we can change LEDs to off/amber/green.
1474          * (track current state ourselves) ... blink for diagnostics,
1475          * power, "this is the one", etc.  EHCI spec supports this.
1476          */
1477
1478         spin_lock_irqsave(&fotg210->lock, flags);
1479         switch (typeReq) {
1480         case ClearHubFeature:
1481                 switch (wValue) {
1482                 case C_HUB_LOCAL_POWER:
1483                 case C_HUB_OVER_CURRENT:
1484                         /* no hub-wide feature/status flags */
1485                         break;
1486                 default:
1487                         goto error;
1488                 }
1489                 break;
1490         case ClearPortFeature:
1491                 if (!wIndex || wIndex > ports)
1492                         goto error;
1493                 wIndex--;
1494                 temp = fotg210_readl(fotg210, status_reg);
1495                 temp &= ~PORT_RWC_BITS;
1496
1497                 /*
1498                  * Even if OWNER is set, so the port is owned by the
1499                  * companion controller, hub_wq needs to be able to clear
1500                  * the port-change status bits (especially
1501                  * USB_PORT_STAT_C_CONNECTION).
1502                  */
1503
1504                 switch (wValue) {
1505                 case USB_PORT_FEAT_ENABLE:
1506                         fotg210_writel(fotg210, temp & ~PORT_PE, status_reg);
1507                         break;
1508                 case USB_PORT_FEAT_C_ENABLE:
1509                         fotg210_writel(fotg210, temp | PORT_PEC, status_reg);
1510                         break;
1511                 case USB_PORT_FEAT_SUSPEND:
1512                         if (temp & PORT_RESET)
1513                                 goto error;
1514                         if (!(temp & PORT_SUSPEND))
1515                                 break;
1516                         if ((temp & PORT_PE) == 0)
1517                                 goto error;
1518
1519                         /* resume signaling for 20 msec */
1520                         fotg210_writel(fotg210, temp | PORT_RESUME, status_reg);
1521                         fotg210->reset_done[wIndex] = jiffies
1522                                         + msecs_to_jiffies(USB_RESUME_TIMEOUT);
1523                         break;
1524                 case USB_PORT_FEAT_C_SUSPEND:
1525                         clear_bit(wIndex, &fotg210->port_c_suspend);
1526                         break;
1527                 case USB_PORT_FEAT_C_CONNECTION:
1528                         fotg210_writel(fotg210, temp | PORT_CSC, status_reg);
1529                         break;
1530                 case USB_PORT_FEAT_C_OVER_CURRENT:
1531                         fotg210_writel(fotg210, temp | OTGISR_OVC,
1532                                         &fotg210->regs->otgisr);
1533                         break;
1534                 case USB_PORT_FEAT_C_RESET:
1535                         /* GetPortStatus clears reset */
1536                         break;
1537                 default:
1538                         goto error;
1539                 }
1540                 fotg210_readl(fotg210, &fotg210->regs->command);
1541                 break;
1542         case GetHubDescriptor:
1543                 fotg210_hub_descriptor(fotg210, (struct usb_hub_descriptor *)
1544                                 buf);
1545                 break;
1546         case GetHubStatus:
1547                 /* no hub-wide feature/status flags */
1548                 memset(buf, 0, 4);
1549                 /*cpu_to_le32s ((u32 *) buf); */
1550                 break;
1551         case GetPortStatus:
1552                 if (!wIndex || wIndex > ports)
1553                         goto error;
1554                 wIndex--;
1555                 status = 0;
1556                 temp = fotg210_readl(fotg210, status_reg);
1557
1558                 /* wPortChange bits */
1559                 if (temp & PORT_CSC)
1560                         status |= USB_PORT_STAT_C_CONNECTION << 16;
1561                 if (temp & PORT_PEC)
1562                         status |= USB_PORT_STAT_C_ENABLE << 16;
1563
1564                 temp1 = fotg210_readl(fotg210, &fotg210->regs->otgisr);
1565                 if (temp1 & OTGISR_OVC)
1566                         status |= USB_PORT_STAT_C_OVERCURRENT << 16;
1567
1568                 /* whoever resumes must GetPortStatus to complete it!! */
1569                 if (temp & PORT_RESUME) {
1570
1571                         /* Remote Wakeup received? */
1572                         if (!fotg210->reset_done[wIndex]) {
1573                                 /* resume signaling for 20 msec */
1574                                 fotg210->reset_done[wIndex] = jiffies
1575                                                 + msecs_to_jiffies(20);
1576                                 /* check the port again */
1577                                 mod_timer(&fotg210_to_hcd(fotg210)->rh_timer,
1578                                                 fotg210->reset_done[wIndex]);
1579                         }
1580
1581                         /* resume completed? */
1582                         else if (time_after_eq(jiffies,
1583                                         fotg210->reset_done[wIndex])) {
1584                                 clear_bit(wIndex, &fotg210->suspended_ports);
1585                                 set_bit(wIndex, &fotg210->port_c_suspend);
1586                                 fotg210->reset_done[wIndex] = 0;
1587
1588                                 /* stop resume signaling */
1589                                 temp = fotg210_readl(fotg210, status_reg);
1590                                 fotg210_writel(fotg210, temp &
1591                                                 ~(PORT_RWC_BITS | PORT_RESUME),
1592                                                 status_reg);
1593                                 clear_bit(wIndex, &fotg210->resuming_ports);
1594                                 retval = handshake(fotg210, status_reg,
1595                                                 PORT_RESUME, 0, 2000);/* 2ms */
1596                                 if (retval != 0) {
1597                                         fotg210_err(fotg210,
1598                                                         "port %d resume error %d\n",
1599                                                         wIndex + 1, retval);
1600                                         goto error;
1601                                 }
1602                                 temp &= ~(PORT_SUSPEND|PORT_RESUME|(3<<10));
1603                         }
1604                 }
1605
1606                 /* whoever resets must GetPortStatus to complete it!! */
1607                 if ((temp & PORT_RESET) && time_after_eq(jiffies,
1608                                 fotg210->reset_done[wIndex])) {
1609                         status |= USB_PORT_STAT_C_RESET << 16;
1610                         fotg210->reset_done[wIndex] = 0;
1611                         clear_bit(wIndex, &fotg210->resuming_ports);
1612
1613                         /* force reset to complete */
1614                         fotg210_writel(fotg210,
1615                                         temp & ~(PORT_RWC_BITS | PORT_RESET),
1616                                         status_reg);
1617                         /* REVISIT:  some hardware needs 550+ usec to clear
1618                          * this bit; seems too long to spin routinely...
1619                          */
1620                         retval = handshake(fotg210, status_reg,
1621                                         PORT_RESET, 0, 1000);
1622                         if (retval != 0) {
1623                                 fotg210_err(fotg210, "port %d reset error %d\n",
1624                                                 wIndex + 1, retval);
1625                                 goto error;
1626                         }
1627
1628                         /* see what we found out */
1629                         temp = check_reset_complete(fotg210, wIndex, status_reg,
1630                                         fotg210_readl(fotg210, status_reg));
1631
1632                         /* restart schedule */
1633                         fotg210->command |= CMD_RUN;
1634                         fotg210_writel(fotg210, fotg210->command, &fotg210->regs->command);
1635                 }
1636
1637                 if (!(temp & (PORT_RESUME|PORT_RESET))) {
1638                         fotg210->reset_done[wIndex] = 0;
1639                         clear_bit(wIndex, &fotg210->resuming_ports);
1640                 }
1641
1642                 /* transfer dedicated ports to the companion hc */
1643                 if ((temp & PORT_CONNECT) &&
1644                                 test_bit(wIndex, &fotg210->companion_ports)) {
1645                         temp &= ~PORT_RWC_BITS;
1646                         fotg210_writel(fotg210, temp, status_reg);
1647                         fotg210_dbg(fotg210, "port %d --> companion\n",
1648                                         wIndex + 1);
1649                         temp = fotg210_readl(fotg210, status_reg);
1650                 }
1651
1652                 /*
1653                  * Even if OWNER is set, there's no harm letting hub_wq
1654                  * see the wPortStatus values (they should all be 0 except
1655                  * for PORT_POWER anyway).
1656                  */
1657
1658                 if (temp & PORT_CONNECT) {
1659                         status |= USB_PORT_STAT_CONNECTION;
1660                         status |= fotg210_port_speed(fotg210, temp);
1661                 }
1662                 if (temp & PORT_PE)
1663                         status |= USB_PORT_STAT_ENABLE;
1664
1665                 /* maybe the port was unsuspended without our knowledge */
1666                 if (temp & (PORT_SUSPEND|PORT_RESUME)) {
1667                         status |= USB_PORT_STAT_SUSPEND;
1668                 } else if (test_bit(wIndex, &fotg210->suspended_ports)) {
1669                         clear_bit(wIndex, &fotg210->suspended_ports);
1670                         clear_bit(wIndex, &fotg210->resuming_ports);
1671                         fotg210->reset_done[wIndex] = 0;
1672                         if (temp & PORT_PE)
1673                                 set_bit(wIndex, &fotg210->port_c_suspend);
1674                 }
1675
1676                 temp1 = fotg210_readl(fotg210, &fotg210->regs->otgisr);
1677                 if (temp1 & OTGISR_OVC)
1678                         status |= USB_PORT_STAT_OVERCURRENT;
1679                 if (temp & PORT_RESET)
1680                         status |= USB_PORT_STAT_RESET;
1681                 if (test_bit(wIndex, &fotg210->port_c_suspend))
1682                         status |= USB_PORT_STAT_C_SUSPEND << 16;
1683
1684                 if (status & ~0xffff)   /* only if wPortChange is interesting */
1685                         dbg_port(fotg210, "GetStatus", wIndex + 1, temp);
1686                 put_unaligned_le32(status, buf);
1687                 break;
1688         case SetHubFeature:
1689                 switch (wValue) {
1690                 case C_HUB_LOCAL_POWER:
1691                 case C_HUB_OVER_CURRENT:
1692                         /* no hub-wide feature/status flags */
1693                         break;
1694                 default:
1695                         goto error;
1696                 }
1697                 break;
1698         case SetPortFeature:
1699                 selector = wIndex >> 8;
1700                 wIndex &= 0xff;
1701
1702                 if (!wIndex || wIndex > ports)
1703                         goto error;
1704                 wIndex--;
1705                 temp = fotg210_readl(fotg210, status_reg);
1706                 temp &= ~PORT_RWC_BITS;
1707                 switch (wValue) {
1708                 case USB_PORT_FEAT_SUSPEND:
1709                         if ((temp & PORT_PE) == 0
1710                                         || (temp & PORT_RESET) != 0)
1711                                 goto error;
1712
1713                         /* After above check the port must be connected.
1714                          * Set appropriate bit thus could put phy into low power
1715                          * mode if we have hostpc feature
1716                          */
1717                         fotg210_writel(fotg210, temp | PORT_SUSPEND,
1718                                         status_reg);
1719                         set_bit(wIndex, &fotg210->suspended_ports);
1720                         break;
1721                 case USB_PORT_FEAT_RESET:
1722                         if (temp & PORT_RESUME)
1723                                 goto error;
1724                         /* line status bits may report this as low speed,
1725                          * which can be fine if this root hub has a
1726                          * transaction translator built in.
1727                          */
1728                         fotg210_dbg(fotg210, "port %d reset\n", wIndex + 1);
1729                         temp |= PORT_RESET;
1730                         temp &= ~PORT_PE;
1731
1732                         /*
1733                          * caller must wait, then call GetPortStatus
1734                          * usb 2.0 spec says 50 ms resets on root
1735                          */
1736                         fotg210->reset_done[wIndex] = jiffies
1737                                         + msecs_to_jiffies(50);
1738                         fotg210_writel(fotg210, temp, status_reg);
1739                         break;
1740
1741                 /* For downstream facing ports (these):  one hub port is put
1742                  * into test mode according to USB2 11.24.2.13, then the hub
1743                  * must be reset (which for root hub now means rmmod+modprobe,
1744                  * or else system reboot).  See EHCI 2.3.9 and 4.14 for info
1745                  * about the EHCI-specific stuff.
1746                  */
1747                 case USB_PORT_FEAT_TEST:
1748                         if (!selector || selector > 5)
1749                                 goto error;
1750                         spin_unlock_irqrestore(&fotg210->lock, flags);
1751                         fotg210_quiesce(fotg210);
1752                         spin_lock_irqsave(&fotg210->lock, flags);
1753
1754                         /* Put all enabled ports into suspend */
1755                         temp = fotg210_readl(fotg210, status_reg) &
1756                                 ~PORT_RWC_BITS;
1757                         if (temp & PORT_PE)
1758                                 fotg210_writel(fotg210, temp | PORT_SUSPEND,
1759                                                 status_reg);
1760
1761                         spin_unlock_irqrestore(&fotg210->lock, flags);
1762                         fotg210_halt(fotg210);
1763                         spin_lock_irqsave(&fotg210->lock, flags);
1764
1765                         temp = fotg210_readl(fotg210, status_reg);
1766                         temp |= selector << 16;
1767                         fotg210_writel(fotg210, temp, status_reg);
1768                         break;
1769
1770                 default:
1771                         goto error;
1772                 }
1773                 fotg210_readl(fotg210, &fotg210->regs->command);
1774                 break;
1775
1776         default:
1777 error:
1778                 /* "stall" on error */
1779                 retval = -EPIPE;
1780         }
1781         spin_unlock_irqrestore(&fotg210->lock, flags);
1782         return retval;
1783 }
1784
1785 static void __maybe_unused fotg210_relinquish_port(struct usb_hcd *hcd,
1786                 int portnum)
1787 {
1788         return;
1789 }
1790
1791 static int __maybe_unused fotg210_port_handed_over(struct usb_hcd *hcd,
1792                 int portnum)
1793 {
1794         return 0;
1795 }
1796
1797 /* There's basically three types of memory:
1798  *      - data used only by the HCD ... kmalloc is fine
1799  *      - async and periodic schedules, shared by HC and HCD ... these
1800  *        need to use dma_pool or dma_alloc_coherent
1801  *      - driver buffers, read/written by HC ... single shot DMA mapped
1802  *
1803  * There's also "register" data (e.g. PCI or SOC), which is memory mapped.
1804  * No memory seen by this driver is pageable.
1805  */
1806
1807 /* Allocate the key transfer structures from the previously allocated pool */
1808 static inline void fotg210_qtd_init(struct fotg210_hcd *fotg210,
1809                 struct fotg210_qtd *qtd, dma_addr_t dma)
1810 {
1811         memset(qtd, 0, sizeof(*qtd));
1812         qtd->qtd_dma = dma;
1813         qtd->hw_token = cpu_to_hc32(fotg210, QTD_STS_HALT);
1814         qtd->hw_next = FOTG210_LIST_END(fotg210);
1815         qtd->hw_alt_next = FOTG210_LIST_END(fotg210);
1816         INIT_LIST_HEAD(&qtd->qtd_list);
1817 }
1818
1819 static struct fotg210_qtd *fotg210_qtd_alloc(struct fotg210_hcd *fotg210,
1820                 gfp_t flags)
1821 {
1822         struct fotg210_qtd *qtd;
1823         dma_addr_t dma;
1824
1825         qtd = dma_pool_alloc(fotg210->qtd_pool, flags, &dma);
1826         if (qtd != NULL)
1827                 fotg210_qtd_init(fotg210, qtd, dma);
1828
1829         return qtd;
1830 }
1831
1832 static inline void fotg210_qtd_free(struct fotg210_hcd *fotg210,
1833                 struct fotg210_qtd *qtd)
1834 {
1835         dma_pool_free(fotg210->qtd_pool, qtd, qtd->qtd_dma);
1836 }
1837
1838
1839 static void qh_destroy(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
1840 {
1841         /* clean qtds first, and know this is not linked */
1842         if (!list_empty(&qh->qtd_list) || qh->qh_next.ptr) {
1843                 fotg210_dbg(fotg210, "unused qh not empty!\n");
1844                 BUG();
1845         }
1846         if (qh->dummy)
1847                 fotg210_qtd_free(fotg210, qh->dummy);
1848         dma_pool_free(fotg210->qh_pool, qh->hw, qh->qh_dma);
1849         kfree(qh);
1850 }
1851
1852 static struct fotg210_qh *fotg210_qh_alloc(struct fotg210_hcd *fotg210,
1853                 gfp_t flags)
1854 {
1855         struct fotg210_qh *qh;
1856         dma_addr_t dma;
1857
1858         qh = kzalloc(sizeof(*qh), GFP_ATOMIC);
1859         if (!qh)
1860                 goto done;
1861         qh->hw = dma_pool_zalloc(fotg210->qh_pool, flags, &dma);
1862         if (!qh->hw)
1863                 goto fail;
1864         qh->qh_dma = dma;
1865         INIT_LIST_HEAD(&qh->qtd_list);
1866
1867         /* dummy td enables safe urb queuing */
1868         qh->dummy = fotg210_qtd_alloc(fotg210, flags);
1869         if (qh->dummy == NULL) {
1870                 fotg210_dbg(fotg210, "no dummy td\n");
1871                 goto fail1;
1872         }
1873 done:
1874         return qh;
1875 fail1:
1876         dma_pool_free(fotg210->qh_pool, qh->hw, qh->qh_dma);
1877 fail:
1878         kfree(qh);
1879         return NULL;
1880 }
1881
1882 /* The queue heads and transfer descriptors are managed from pools tied
1883  * to each of the "per device" structures.
1884  * This is the initialisation and cleanup code.
1885  */
1886
1887 static void fotg210_mem_cleanup(struct fotg210_hcd *fotg210)
1888 {
1889         if (fotg210->async)
1890                 qh_destroy(fotg210, fotg210->async);
1891         fotg210->async = NULL;
1892
1893         if (fotg210->dummy)
1894                 qh_destroy(fotg210, fotg210->dummy);
1895         fotg210->dummy = NULL;
1896
1897         /* DMA consistent memory and pools */
1898         dma_pool_destroy(fotg210->qtd_pool);
1899         fotg210->qtd_pool = NULL;
1900
1901         dma_pool_destroy(fotg210->qh_pool);
1902         fotg210->qh_pool = NULL;
1903
1904         dma_pool_destroy(fotg210->itd_pool);
1905         fotg210->itd_pool = NULL;
1906
1907         if (fotg210->periodic)
1908                 dma_free_coherent(fotg210_to_hcd(fotg210)->self.controller,
1909                                 fotg210->periodic_size * sizeof(u32),
1910                                 fotg210->periodic, fotg210->periodic_dma);
1911         fotg210->periodic = NULL;
1912
1913         /* shadow periodic table */
1914         kfree(fotg210->pshadow);
1915         fotg210->pshadow = NULL;
1916 }
1917
1918 /* remember to add cleanup code (above) if you add anything here */
1919 static int fotg210_mem_init(struct fotg210_hcd *fotg210, gfp_t flags)
1920 {
1921         int i;
1922
1923         /* QTDs for control/bulk/intr transfers */
1924         fotg210->qtd_pool = dma_pool_create("fotg210_qtd",
1925                         fotg210_to_hcd(fotg210)->self.controller,
1926                         sizeof(struct fotg210_qtd),
1927                         32 /* byte alignment (for hw parts) */,
1928                         4096 /* can't cross 4K */);
1929         if (!fotg210->qtd_pool)
1930                 goto fail;
1931
1932         /* QHs for control/bulk/intr transfers */
1933         fotg210->qh_pool = dma_pool_create("fotg210_qh",
1934                         fotg210_to_hcd(fotg210)->self.controller,
1935                         sizeof(struct fotg210_qh_hw),
1936                         32 /* byte alignment (for hw parts) */,
1937                         4096 /* can't cross 4K */);
1938         if (!fotg210->qh_pool)
1939                 goto fail;
1940
1941         fotg210->async = fotg210_qh_alloc(fotg210, flags);
1942         if (!fotg210->async)
1943                 goto fail;
1944
1945         /* ITD for high speed ISO transfers */
1946         fotg210->itd_pool = dma_pool_create("fotg210_itd",
1947                         fotg210_to_hcd(fotg210)->self.controller,
1948                         sizeof(struct fotg210_itd),
1949                         64 /* byte alignment (for hw parts) */,
1950                         4096 /* can't cross 4K */);
1951         if (!fotg210->itd_pool)
1952                 goto fail;
1953
1954         /* Hardware periodic table */
1955         fotg210->periodic =
1956                 dma_alloc_coherent(fotg210_to_hcd(fotg210)->self.controller,
1957                                 fotg210->periodic_size * sizeof(__le32),
1958                                 &fotg210->periodic_dma, 0);
1959         if (fotg210->periodic == NULL)
1960                 goto fail;
1961
1962         for (i = 0; i < fotg210->periodic_size; i++)
1963                 fotg210->periodic[i] = FOTG210_LIST_END(fotg210);
1964
1965         /* software shadow of hardware table */
1966         fotg210->pshadow = kcalloc(fotg210->periodic_size, sizeof(void *),
1967                         flags);
1968         if (fotg210->pshadow != NULL)
1969                 return 0;
1970
1971 fail:
1972         fotg210_dbg(fotg210, "couldn't init memory\n");
1973         fotg210_mem_cleanup(fotg210);
1974         return -ENOMEM;
1975 }
1976 /* EHCI hardware queue manipulation ... the core.  QH/QTD manipulation.
1977  *
1978  * Control, bulk, and interrupt traffic all use "qh" lists.  They list "qtd"
1979  * entries describing USB transactions, max 16-20kB/entry (with 4kB-aligned
1980  * buffers needed for the larger number).  We use one QH per endpoint, queue
1981  * multiple urbs (all three types) per endpoint.  URBs may need several qtds.
1982  *
1983  * ISO traffic uses "ISO TD" (itd) records, and (along with
1984  * interrupts) needs careful scheduling.  Performance improvements can be
1985  * an ongoing challenge.  That's in "ehci-sched.c".
1986  *
1987  * USB 1.1 devices are handled (a) by "companion" OHCI or UHCI root hubs,
1988  * or otherwise through transaction translators (TTs) in USB 2.0 hubs using
1989  * (b) special fields in qh entries or (c) split iso entries.  TTs will
1990  * buffer low/full speed data so the host collects it at high speed.
1991  */
1992
1993 /* fill a qtd, returning how much of the buffer we were able to queue up */
1994 static int qtd_fill(struct fotg210_hcd *fotg210, struct fotg210_qtd *qtd,
1995                 dma_addr_t buf, size_t len, int token, int maxpacket)
1996 {
1997         int i, count;
1998         u64 addr = buf;
1999
2000         /* one buffer entry per 4K ... first might be short or unaligned */
2001         qtd->hw_buf[0] = cpu_to_hc32(fotg210, (u32)addr);
2002         qtd->hw_buf_hi[0] = cpu_to_hc32(fotg210, (u32)(addr >> 32));
2003         count = 0x1000 - (buf & 0x0fff);        /* rest of that page */
2004         if (likely(len < count))                /* ... iff needed */
2005                 count = len;
2006         else {
2007                 buf +=  0x1000;
2008                 buf &= ~0x0fff;
2009
2010                 /* per-qtd limit: from 16K to 20K (best alignment) */
2011                 for (i = 1; count < len && i < 5; i++) {
2012                         addr = buf;
2013                         qtd->hw_buf[i] = cpu_to_hc32(fotg210, (u32)addr);
2014                         qtd->hw_buf_hi[i] = cpu_to_hc32(fotg210,
2015                                         (u32)(addr >> 32));
2016                         buf += 0x1000;
2017                         if ((count + 0x1000) < len)
2018                                 count += 0x1000;
2019                         else
2020                                 count = len;
2021                 }
2022
2023                 /* short packets may only terminate transfers */
2024                 if (count != len)
2025                         count -= (count % maxpacket);
2026         }
2027         qtd->hw_token = cpu_to_hc32(fotg210, (count << 16) | token);
2028         qtd->length = count;
2029
2030         return count;
2031 }
2032
2033 static inline void qh_update(struct fotg210_hcd *fotg210,
2034                 struct fotg210_qh *qh, struct fotg210_qtd *qtd)
2035 {
2036         struct fotg210_qh_hw *hw = qh->hw;
2037
2038         /* writes to an active overlay are unsafe */
2039         BUG_ON(qh->qh_state != QH_STATE_IDLE);
2040
2041         hw->hw_qtd_next = QTD_NEXT(fotg210, qtd->qtd_dma);
2042         hw->hw_alt_next = FOTG210_LIST_END(fotg210);
2043
2044         /* Except for control endpoints, we make hardware maintain data
2045          * toggle (like OHCI) ... here (re)initialize the toggle in the QH,
2046          * and set the pseudo-toggle in udev. Only usb_clear_halt() will
2047          * ever clear it.
2048          */
2049         if (!(hw->hw_info1 & cpu_to_hc32(fotg210, QH_TOGGLE_CTL))) {
2050                 unsigned is_out, epnum;
2051
2052                 is_out = qh->is_out;
2053                 epnum = (hc32_to_cpup(fotg210, &hw->hw_info1) >> 8) & 0x0f;
2054                 if (unlikely(!usb_gettoggle(qh->dev, epnum, is_out))) {
2055                         hw->hw_token &= ~cpu_to_hc32(fotg210, QTD_TOGGLE);
2056                         usb_settoggle(qh->dev, epnum, is_out, 1);
2057                 }
2058         }
2059
2060         hw->hw_token &= cpu_to_hc32(fotg210, QTD_TOGGLE | QTD_STS_PING);
2061 }
2062
2063 /* if it weren't for a common silicon quirk (writing the dummy into the qh
2064  * overlay, so qh->hw_token wrongly becomes inactive/halted), only fault
2065  * recovery (including urb dequeue) would need software changes to a QH...
2066  */
2067 static void qh_refresh(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
2068 {
2069         struct fotg210_qtd *qtd;
2070
2071         if (list_empty(&qh->qtd_list))
2072                 qtd = qh->dummy;
2073         else {
2074                 qtd = list_entry(qh->qtd_list.next,
2075                                 struct fotg210_qtd, qtd_list);
2076                 /*
2077                  * first qtd may already be partially processed.
2078                  * If we come here during unlink, the QH overlay region
2079                  * might have reference to the just unlinked qtd. The
2080                  * qtd is updated in qh_completions(). Update the QH
2081                  * overlay here.
2082                  */
2083                 if (cpu_to_hc32(fotg210, qtd->qtd_dma) == qh->hw->hw_current) {
2084                         qh->hw->hw_qtd_next = qtd->hw_next;
2085                         qtd = NULL;
2086                 }
2087         }
2088
2089         if (qtd)
2090                 qh_update(fotg210, qh, qtd);
2091 }
2092
2093 static void qh_link_async(struct fotg210_hcd *fotg210, struct fotg210_qh *qh);
2094
2095 static void fotg210_clear_tt_buffer_complete(struct usb_hcd *hcd,
2096                 struct usb_host_endpoint *ep)
2097 {
2098         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
2099         struct fotg210_qh *qh = ep->hcpriv;
2100         unsigned long flags;
2101
2102         spin_lock_irqsave(&fotg210->lock, flags);
2103         qh->clearing_tt = 0;
2104         if (qh->qh_state == QH_STATE_IDLE && !list_empty(&qh->qtd_list)
2105                         && fotg210->rh_state == FOTG210_RH_RUNNING)
2106                 qh_link_async(fotg210, qh);
2107         spin_unlock_irqrestore(&fotg210->lock, flags);
2108 }
2109
2110 static void fotg210_clear_tt_buffer(struct fotg210_hcd *fotg210,
2111                 struct fotg210_qh *qh, struct urb *urb, u32 token)
2112 {
2113
2114         /* If an async split transaction gets an error or is unlinked,
2115          * the TT buffer may be left in an indeterminate state.  We
2116          * have to clear the TT buffer.
2117          *
2118          * Note: this routine is never called for Isochronous transfers.
2119          */
2120         if (urb->dev->tt && !usb_pipeint(urb->pipe) && !qh->clearing_tt) {
2121                 struct usb_device *tt = urb->dev->tt->hub;
2122
2123                 dev_dbg(&tt->dev,
2124                                 "clear tt buffer port %d, a%d ep%d t%08x\n",
2125                                 urb->dev->ttport, urb->dev->devnum,
2126                                 usb_pipeendpoint(urb->pipe), token);
2127
2128                 if (urb->dev->tt->hub !=
2129                                 fotg210_to_hcd(fotg210)->self.root_hub) {
2130                         if (usb_hub_clear_tt_buffer(urb) == 0)
2131                                 qh->clearing_tt = 1;
2132                 }
2133         }
2134 }
2135
2136 static int qtd_copy_status(struct fotg210_hcd *fotg210, struct urb *urb,
2137                 size_t length, u32 token)
2138 {
2139         int status = -EINPROGRESS;
2140
2141         /* count IN/OUT bytes, not SETUP (even short packets) */
2142         if (likely(QTD_PID(token) != 2))
2143                 urb->actual_length += length - QTD_LENGTH(token);
2144
2145         /* don't modify error codes */
2146         if (unlikely(urb->unlinked))
2147                 return status;
2148
2149         /* force cleanup after short read; not always an error */
2150         if (unlikely(IS_SHORT_READ(token)))
2151                 status = -EREMOTEIO;
2152
2153         /* serious "can't proceed" faults reported by the hardware */
2154         if (token & QTD_STS_HALT) {
2155                 if (token & QTD_STS_BABBLE) {
2156                         /* FIXME "must" disable babbling device's port too */
2157                         status = -EOVERFLOW;
2158                 /* CERR nonzero + halt --> stall */
2159                 } else if (QTD_CERR(token)) {
2160                         status = -EPIPE;
2161
2162                 /* In theory, more than one of the following bits can be set
2163                  * since they are sticky and the transaction is retried.
2164                  * Which to test first is rather arbitrary.
2165                  */
2166                 } else if (token & QTD_STS_MMF) {
2167                         /* fs/ls interrupt xfer missed the complete-split */
2168                         status = -EPROTO;
2169                 } else if (token & QTD_STS_DBE) {
2170                         status = (QTD_PID(token) == 1) /* IN ? */
2171                                 ? -ENOSR  /* hc couldn't read data */
2172                                 : -ECOMM; /* hc couldn't write data */
2173                 } else if (token & QTD_STS_XACT) {
2174                         /* timeout, bad CRC, wrong PID, etc */
2175                         fotg210_dbg(fotg210, "devpath %s ep%d%s 3strikes\n",
2176                                         urb->dev->devpath,
2177                                         usb_pipeendpoint(urb->pipe),
2178                                         usb_pipein(urb->pipe) ? "in" : "out");
2179                         status = -EPROTO;
2180                 } else {        /* unknown */
2181                         status = -EPROTO;
2182                 }
2183
2184                 fotg210_dbg(fotg210,
2185                                 "dev%d ep%d%s qtd token %08x --> status %d\n",
2186                                 usb_pipedevice(urb->pipe),
2187                                 usb_pipeendpoint(urb->pipe),
2188                                 usb_pipein(urb->pipe) ? "in" : "out",
2189                                 token, status);
2190         }
2191
2192         return status;
2193 }
2194
2195 static void fotg210_urb_done(struct fotg210_hcd *fotg210, struct urb *urb,
2196                 int status)
2197 __releases(fotg210->lock)
2198 __acquires(fotg210->lock)
2199 {
2200         if (likely(urb->hcpriv != NULL)) {
2201                 struct fotg210_qh *qh = (struct fotg210_qh *) urb->hcpriv;
2202
2203                 /* S-mask in a QH means it's an interrupt urb */
2204                 if ((qh->hw->hw_info2 & cpu_to_hc32(fotg210, QH_SMASK)) != 0) {
2205
2206                         /* ... update hc-wide periodic stats (for usbfs) */
2207                         fotg210_to_hcd(fotg210)->self.bandwidth_int_reqs--;
2208                 }
2209         }
2210
2211         if (unlikely(urb->unlinked)) {
2212                 INCR(fotg210->stats.unlink);
2213         } else {
2214                 /* report non-error and short read status as zero */
2215                 if (status == -EINPROGRESS || status == -EREMOTEIO)
2216                         status = 0;
2217                 INCR(fotg210->stats.complete);
2218         }
2219
2220 #ifdef FOTG210_URB_TRACE
2221         fotg210_dbg(fotg210,
2222                         "%s %s urb %p ep%d%s status %d len %d/%d\n",
2223                         __func__, urb->dev->devpath, urb,
2224                         usb_pipeendpoint(urb->pipe),
2225                         usb_pipein(urb->pipe) ? "in" : "out",
2226                         status,
2227                         urb->actual_length, urb->transfer_buffer_length);
2228 #endif
2229
2230         /* complete() can reenter this HCD */
2231         usb_hcd_unlink_urb_from_ep(fotg210_to_hcd(fotg210), urb);
2232         spin_unlock(&fotg210->lock);
2233         usb_hcd_giveback_urb(fotg210_to_hcd(fotg210), urb, status);
2234         spin_lock(&fotg210->lock);
2235 }
2236
2237 static int qh_schedule(struct fotg210_hcd *fotg210, struct fotg210_qh *qh);
2238
2239 /* Process and free completed qtds for a qh, returning URBs to drivers.
2240  * Chases up to qh->hw_current.  Returns number of completions called,
2241  * indicating how much "real" work we did.
2242  */
2243 static unsigned qh_completions(struct fotg210_hcd *fotg210,
2244                 struct fotg210_qh *qh)
2245 {
2246         struct fotg210_qtd *last, *end = qh->dummy;
2247         struct fotg210_qtd *qtd, *tmp;
2248         int last_status;
2249         int stopped;
2250         unsigned count = 0;
2251         u8 state;
2252         struct fotg210_qh_hw *hw = qh->hw;
2253
2254         if (unlikely(list_empty(&qh->qtd_list)))
2255                 return count;
2256
2257         /* completions (or tasks on other cpus) must never clobber HALT
2258          * till we've gone through and cleaned everything up, even when
2259          * they add urbs to this qh's queue or mark them for unlinking.
2260          *
2261          * NOTE:  unlinking expects to be done in queue order.
2262          *
2263          * It's a bug for qh->qh_state to be anything other than
2264          * QH_STATE_IDLE, unless our caller is scan_async() or
2265          * scan_intr().
2266          */
2267         state = qh->qh_state;
2268         qh->qh_state = QH_STATE_COMPLETING;
2269         stopped = (state == QH_STATE_IDLE);
2270
2271 rescan:
2272         last = NULL;
2273         last_status = -EINPROGRESS;
2274         qh->needs_rescan = 0;
2275
2276         /* remove de-activated QTDs from front of queue.
2277          * after faults (including short reads), cleanup this urb
2278          * then let the queue advance.
2279          * if queue is stopped, handles unlinks.
2280          */
2281         list_for_each_entry_safe(qtd, tmp, &qh->qtd_list, qtd_list) {
2282                 struct urb *urb;
2283                 u32 token = 0;
2284
2285                 urb = qtd->urb;
2286
2287                 /* clean up any state from previous QTD ...*/
2288                 if (last) {
2289                         if (likely(last->urb != urb)) {
2290                                 fotg210_urb_done(fotg210, last->urb,
2291                                                 last_status);
2292                                 count++;
2293                                 last_status = -EINPROGRESS;
2294                         }
2295                         fotg210_qtd_free(fotg210, last);
2296                         last = NULL;
2297                 }
2298
2299                 /* ignore urbs submitted during completions we reported */
2300                 if (qtd == end)
2301                         break;
2302
2303                 /* hardware copies qtd out of qh overlay */
2304                 rmb();
2305                 token = hc32_to_cpu(fotg210, qtd->hw_token);
2306
2307                 /* always clean up qtds the hc de-activated */
2308 retry_xacterr:
2309                 if ((token & QTD_STS_ACTIVE) == 0) {
2310
2311                         /* Report Data Buffer Error: non-fatal but useful */
2312                         if (token & QTD_STS_DBE)
2313                                 fotg210_dbg(fotg210,
2314                                         "detected DataBufferErr for urb %p ep%d%s len %d, qtd %p [qh %p]\n",
2315                                         urb, usb_endpoint_num(&urb->ep->desc),
2316                                         usb_endpoint_dir_in(&urb->ep->desc)
2317                                                 ? "in" : "out",
2318                                         urb->transfer_buffer_length, qtd, qh);
2319
2320                         /* on STALL, error, and short reads this urb must
2321                          * complete and all its qtds must be recycled.
2322                          */
2323                         if ((token & QTD_STS_HALT) != 0) {
2324
2325                                 /* retry transaction errors until we
2326                                  * reach the software xacterr limit
2327                                  */
2328                                 if ((token & QTD_STS_XACT) &&
2329                                                 QTD_CERR(token) == 0 &&
2330                                                 ++qh->xacterrs < QH_XACTERR_MAX &&
2331                                                 !urb->unlinked) {
2332                                         fotg210_dbg(fotg210,
2333                                                 "detected XactErr len %zu/%zu retry %d\n",
2334                                                 qtd->length - QTD_LENGTH(token),
2335                                                 qtd->length,
2336                                                 qh->xacterrs);
2337
2338                                         /* reset the token in the qtd and the
2339                                          * qh overlay (which still contains
2340                                          * the qtd) so that we pick up from
2341                                          * where we left off
2342                                          */
2343                                         token &= ~QTD_STS_HALT;
2344                                         token |= QTD_STS_ACTIVE |
2345                                                  (FOTG210_TUNE_CERR << 10);
2346                                         qtd->hw_token = cpu_to_hc32(fotg210,
2347                                                         token);
2348                                         wmb();
2349                                         hw->hw_token = cpu_to_hc32(fotg210,
2350                                                         token);
2351                                         goto retry_xacterr;
2352                                 }
2353                                 stopped = 1;
2354
2355                         /* magic dummy for some short reads; qh won't advance.
2356                          * that silicon quirk can kick in with this dummy too.
2357                          *
2358                          * other short reads won't stop the queue, including
2359                          * control transfers (status stage handles that) or
2360                          * most other single-qtd reads ... the queue stops if
2361                          * URB_SHORT_NOT_OK was set so the driver submitting
2362                          * the urbs could clean it up.
2363                          */
2364                         } else if (IS_SHORT_READ(token) &&
2365                                         !(qtd->hw_alt_next &
2366                                         FOTG210_LIST_END(fotg210))) {
2367                                 stopped = 1;
2368                         }
2369
2370                 /* stop scanning when we reach qtds the hc is using */
2371                 } else if (likely(!stopped
2372                                 && fotg210->rh_state >= FOTG210_RH_RUNNING)) {
2373                         break;
2374
2375                 /* scan the whole queue for unlinks whenever it stops */
2376                 } else {
2377                         stopped = 1;
2378
2379                         /* cancel everything if we halt, suspend, etc */
2380                         if (fotg210->rh_state < FOTG210_RH_RUNNING)
2381                                 last_status = -ESHUTDOWN;
2382
2383                         /* this qtd is active; skip it unless a previous qtd
2384                          * for its urb faulted, or its urb was canceled.
2385                          */
2386                         else if (last_status == -EINPROGRESS && !urb->unlinked)
2387                                 continue;
2388
2389                         /* qh unlinked; token in overlay may be most current */
2390                         if (state == QH_STATE_IDLE &&
2391                                         cpu_to_hc32(fotg210, qtd->qtd_dma)
2392                                         == hw->hw_current) {
2393                                 token = hc32_to_cpu(fotg210, hw->hw_token);
2394
2395                                 /* An unlink may leave an incomplete
2396                                  * async transaction in the TT buffer.
2397                                  * We have to clear it.
2398                                  */
2399                                 fotg210_clear_tt_buffer(fotg210, qh, urb,
2400                                                 token);
2401                         }
2402                 }
2403
2404                 /* unless we already know the urb's status, collect qtd status
2405                  * and update count of bytes transferred.  in common short read
2406                  * cases with only one data qtd (including control transfers),
2407                  * queue processing won't halt.  but with two or more qtds (for
2408                  * example, with a 32 KB transfer), when the first qtd gets a
2409                  * short read the second must be removed by hand.
2410                  */
2411                 if (last_status == -EINPROGRESS) {
2412                         last_status = qtd_copy_status(fotg210, urb,
2413                                         qtd->length, token);
2414                         if (last_status == -EREMOTEIO &&
2415                                         (qtd->hw_alt_next &
2416                                         FOTG210_LIST_END(fotg210)))
2417                                 last_status = -EINPROGRESS;
2418
2419                         /* As part of low/full-speed endpoint-halt processing
2420                          * we must clear the TT buffer (11.17.5).
2421                          */
2422                         if (unlikely(last_status != -EINPROGRESS &&
2423                                         last_status != -EREMOTEIO)) {
2424                                 /* The TT's in some hubs malfunction when they
2425                                  * receive this request following a STALL (they
2426                                  * stop sending isochronous packets).  Since a
2427                                  * STALL can't leave the TT buffer in a busy
2428                                  * state (if you believe Figures 11-48 - 11-51
2429                                  * in the USB 2.0 spec), we won't clear the TT
2430                                  * buffer in this case.  Strictly speaking this
2431                                  * is a violation of the spec.
2432                                  */
2433                                 if (last_status != -EPIPE)
2434                                         fotg210_clear_tt_buffer(fotg210, qh,
2435                                                         urb, token);
2436                         }
2437                 }
2438
2439                 /* if we're removing something not at the queue head,
2440                  * patch the hardware queue pointer.
2441                  */
2442                 if (stopped && qtd->qtd_list.prev != &qh->qtd_list) {
2443                         last = list_entry(qtd->qtd_list.prev,
2444                                         struct fotg210_qtd, qtd_list);
2445                         last->hw_next = qtd->hw_next;
2446                 }
2447
2448                 /* remove qtd; it's recycled after possible urb completion */
2449                 list_del(&qtd->qtd_list);
2450                 last = qtd;
2451
2452                 /* reinit the xacterr counter for the next qtd */
2453                 qh->xacterrs = 0;
2454         }
2455
2456         /* last urb's completion might still need calling */
2457         if (likely(last != NULL)) {
2458                 fotg210_urb_done(fotg210, last->urb, last_status);
2459                 count++;
2460                 fotg210_qtd_free(fotg210, last);
2461         }
2462
2463         /* Do we need to rescan for URBs dequeued during a giveback? */
2464         if (unlikely(qh->needs_rescan)) {
2465                 /* If the QH is already unlinked, do the rescan now. */
2466                 if (state == QH_STATE_IDLE)
2467                         goto rescan;
2468
2469                 /* Otherwise we have to wait until the QH is fully unlinked.
2470                  * Our caller will start an unlink if qh->needs_rescan is
2471                  * set.  But if an unlink has already started, nothing needs
2472                  * to be done.
2473                  */
2474                 if (state != QH_STATE_LINKED)
2475                         qh->needs_rescan = 0;
2476         }
2477
2478         /* restore original state; caller must unlink or relink */
2479         qh->qh_state = state;
2480
2481         /* be sure the hardware's done with the qh before refreshing
2482          * it after fault cleanup, or recovering from silicon wrongly
2483          * overlaying the dummy qtd (which reduces DMA chatter).
2484          */
2485         if (stopped != 0 || hw->hw_qtd_next == FOTG210_LIST_END(fotg210)) {
2486                 switch (state) {
2487                 case QH_STATE_IDLE:
2488                         qh_refresh(fotg210, qh);
2489                         break;
2490                 case QH_STATE_LINKED:
2491                         /* We won't refresh a QH that's linked (after the HC
2492                          * stopped the queue).  That avoids a race:
2493                          *  - HC reads first part of QH;
2494                          *  - CPU updates that first part and the token;
2495                          *  - HC reads rest of that QH, including token
2496                          * Result:  HC gets an inconsistent image, and then
2497                          * DMAs to/from the wrong memory (corrupting it).
2498                          *
2499                          * That should be rare for interrupt transfers,
2500                          * except maybe high bandwidth ...
2501                          */
2502
2503                         /* Tell the caller to start an unlink */
2504                         qh->needs_rescan = 1;
2505                         break;
2506                 /* otherwise, unlink already started */
2507                 }
2508         }
2509
2510         return count;
2511 }
2512
2513 /* high bandwidth multiplier, as encoded in highspeed endpoint descriptors */
2514 #define hb_mult(wMaxPacketSize) (1 + (((wMaxPacketSize) >> 11) & 0x03))
2515 /* ... and packet size, for any kind of endpoint descriptor */
2516 #define max_packet(wMaxPacketSize) ((wMaxPacketSize) & 0x07ff)
2517
2518 /* reverse of qh_urb_transaction:  free a list of TDs.
2519  * used for cleanup after errors, before HC sees an URB's TDs.
2520  */
2521 static void qtd_list_free(struct fotg210_hcd *fotg210, struct urb *urb,
2522                 struct list_head *head)
2523 {
2524         struct fotg210_qtd *qtd, *temp;
2525
2526         list_for_each_entry_safe(qtd, temp, head, qtd_list) {
2527                 list_del(&qtd->qtd_list);
2528                 fotg210_qtd_free(fotg210, qtd);
2529         }
2530 }
2531
2532 /* create a list of filled qtds for this URB; won't link into qh.
2533  */
2534 static struct list_head *qh_urb_transaction(struct fotg210_hcd *fotg210,
2535                 struct urb *urb, struct list_head *head, gfp_t flags)
2536 {
2537         struct fotg210_qtd *qtd, *qtd_prev;
2538         dma_addr_t buf;
2539         int len, this_sg_len, maxpacket;
2540         int is_input;
2541         u32 token;
2542         int i;
2543         struct scatterlist *sg;
2544
2545         /*
2546          * URBs map to sequences of QTDs:  one logical transaction
2547          */
2548         qtd = fotg210_qtd_alloc(fotg210, flags);
2549         if (unlikely(!qtd))
2550                 return NULL;
2551         list_add_tail(&qtd->qtd_list, head);
2552         qtd->urb = urb;
2553
2554         token = QTD_STS_ACTIVE;
2555         token |= (FOTG210_TUNE_CERR << 10);
2556         /* for split transactions, SplitXState initialized to zero */
2557
2558         len = urb->transfer_buffer_length;
2559         is_input = usb_pipein(urb->pipe);
2560         if (usb_pipecontrol(urb->pipe)) {
2561                 /* SETUP pid */
2562                 qtd_fill(fotg210, qtd, urb->setup_dma,
2563                                 sizeof(struct usb_ctrlrequest),
2564                                 token | (2 /* "setup" */ << 8), 8);
2565
2566                 /* ... and always at least one more pid */
2567                 token ^= QTD_TOGGLE;
2568                 qtd_prev = qtd;
2569                 qtd = fotg210_qtd_alloc(fotg210, flags);
2570                 if (unlikely(!qtd))
2571                         goto cleanup;
2572                 qtd->urb = urb;
2573                 qtd_prev->hw_next = QTD_NEXT(fotg210, qtd->qtd_dma);
2574                 list_add_tail(&qtd->qtd_list, head);
2575
2576                 /* for zero length DATA stages, STATUS is always IN */
2577                 if (len == 0)
2578                         token |= (1 /* "in" */ << 8);
2579         }
2580
2581         /*
2582          * data transfer stage:  buffer setup
2583          */
2584         i = urb->num_mapped_sgs;
2585         if (len > 0 && i > 0) {
2586                 sg = urb->sg;
2587                 buf = sg_dma_address(sg);
2588
2589                 /* urb->transfer_buffer_length may be smaller than the
2590                  * size of the scatterlist (or vice versa)
2591                  */
2592                 this_sg_len = min_t(int, sg_dma_len(sg), len);
2593         } else {
2594                 sg = NULL;
2595                 buf = urb->transfer_dma;
2596                 this_sg_len = len;
2597         }
2598
2599         if (is_input)
2600                 token |= (1 /* "in" */ << 8);
2601         /* else it's already initted to "out" pid (0 << 8) */
2602
2603         maxpacket = max_packet(usb_maxpacket(urb->dev, urb->pipe, !is_input));
2604
2605         /*
2606          * buffer gets wrapped in one or more qtds;
2607          * last one may be "short" (including zero len)
2608          * and may serve as a control status ack
2609          */
2610         for (;;) {
2611                 int this_qtd_len;
2612
2613                 this_qtd_len = qtd_fill(fotg210, qtd, buf, this_sg_len, token,
2614                                 maxpacket);
2615                 this_sg_len -= this_qtd_len;
2616                 len -= this_qtd_len;
2617                 buf += this_qtd_len;
2618
2619                 /*
2620                  * short reads advance to a "magic" dummy instead of the next
2621                  * qtd ... that forces the queue to stop, for manual cleanup.
2622                  * (this will usually be overridden later.)
2623                  */
2624                 if (is_input)
2625                         qtd->hw_alt_next = fotg210->async->hw->hw_alt_next;
2626
2627                 /* qh makes control packets use qtd toggle; maybe switch it */
2628                 if ((maxpacket & (this_qtd_len + (maxpacket - 1))) == 0)
2629                         token ^= QTD_TOGGLE;
2630
2631                 if (likely(this_sg_len <= 0)) {
2632                         if (--i <= 0 || len <= 0)
2633                                 break;
2634                         sg = sg_next(sg);
2635                         buf = sg_dma_address(sg);
2636                         this_sg_len = min_t(int, sg_dma_len(sg), len);
2637                 }
2638
2639                 qtd_prev = qtd;
2640                 qtd = fotg210_qtd_alloc(fotg210, flags);
2641                 if (unlikely(!qtd))
2642                         goto cleanup;
2643                 qtd->urb = urb;
2644                 qtd_prev->hw_next = QTD_NEXT(fotg210, qtd->qtd_dma);
2645                 list_add_tail(&qtd->qtd_list, head);
2646         }
2647
2648         /*
2649          * unless the caller requires manual cleanup after short reads,
2650          * have the alt_next mechanism keep the queue running after the
2651          * last data qtd (the only one, for control and most other cases).
2652          */
2653         if (likely((urb->transfer_flags & URB_SHORT_NOT_OK) == 0 ||
2654                         usb_pipecontrol(urb->pipe)))
2655                 qtd->hw_alt_next = FOTG210_LIST_END(fotg210);
2656
2657         /*
2658          * control requests may need a terminating data "status" ack;
2659          * other OUT ones may need a terminating short packet
2660          * (zero length).
2661          */
2662         if (likely(urb->transfer_buffer_length != 0)) {
2663                 int one_more = 0;
2664
2665                 if (usb_pipecontrol(urb->pipe)) {
2666                         one_more = 1;
2667                         token ^= 0x0100;        /* "in" <--> "out"  */
2668                         token |= QTD_TOGGLE;    /* force DATA1 */
2669                 } else if (usb_pipeout(urb->pipe)
2670                                 && (urb->transfer_flags & URB_ZERO_PACKET)
2671                                 && !(urb->transfer_buffer_length % maxpacket)) {
2672                         one_more = 1;
2673                 }
2674                 if (one_more) {
2675                         qtd_prev = qtd;
2676                         qtd = fotg210_qtd_alloc(fotg210, flags);
2677                         if (unlikely(!qtd))
2678                                 goto cleanup;
2679                         qtd->urb = urb;
2680                         qtd_prev->hw_next = QTD_NEXT(fotg210, qtd->qtd_dma);
2681                         list_add_tail(&qtd->qtd_list, head);
2682
2683                         /* never any data in such packets */
2684                         qtd_fill(fotg210, qtd, 0, 0, token, 0);
2685                 }
2686         }
2687
2688         /* by default, enable interrupt on urb completion */
2689         if (likely(!(urb->transfer_flags & URB_NO_INTERRUPT)))
2690                 qtd->hw_token |= cpu_to_hc32(fotg210, QTD_IOC);
2691         return head;
2692
2693 cleanup:
2694         qtd_list_free(fotg210, urb, head);
2695         return NULL;
2696 }
2697
2698 /* Would be best to create all qh's from config descriptors,
2699  * when each interface/altsetting is established.  Unlink
2700  * any previous qh and cancel its urbs first; endpoints are
2701  * implicitly reset then (data toggle too).
2702  * That'd mean updating how usbcore talks to HCDs. (2.7?)
2703  */
2704
2705
2706 /* Each QH holds a qtd list; a QH is used for everything except iso.
2707  *
2708  * For interrupt urbs, the scheduler must set the microframe scheduling
2709  * mask(s) each time the QH gets scheduled.  For highspeed, that's
2710  * just one microframe in the s-mask.  For split interrupt transactions
2711  * there are additional complications: c-mask, maybe FSTNs.
2712  */
2713 static struct fotg210_qh *qh_make(struct fotg210_hcd *fotg210, struct urb *urb,
2714                 gfp_t flags)
2715 {
2716         struct fotg210_qh *qh = fotg210_qh_alloc(fotg210, flags);
2717         u32 info1 = 0, info2 = 0;
2718         int is_input, type;
2719         int maxp = 0;
2720         struct usb_tt *tt = urb->dev->tt;
2721         struct fotg210_qh_hw *hw;
2722
2723         if (!qh)
2724                 return qh;
2725
2726         /*
2727          * init endpoint/device data for this QH
2728          */
2729         info1 |= usb_pipeendpoint(urb->pipe) << 8;
2730         info1 |= usb_pipedevice(urb->pipe) << 0;
2731
2732         is_input = usb_pipein(urb->pipe);
2733         type = usb_pipetype(urb->pipe);
2734         maxp = usb_maxpacket(urb->dev, urb->pipe, !is_input);
2735
2736         /* 1024 byte maxpacket is a hardware ceiling.  High bandwidth
2737          * acts like up to 3KB, but is built from smaller packets.
2738          */
2739         if (max_packet(maxp) > 1024) {
2740                 fotg210_dbg(fotg210, "bogus qh maxpacket %d\n",
2741                                 max_packet(maxp));
2742                 goto done;
2743         }
2744
2745         /* Compute interrupt scheduling parameters just once, and save.
2746          * - allowing for high bandwidth, how many nsec/uframe are used?
2747          * - split transactions need a second CSPLIT uframe; same question
2748          * - splits also need a schedule gap (for full/low speed I/O)
2749          * - qh has a polling interval
2750          *
2751          * For control/bulk requests, the HC or TT handles these.
2752          */
2753         if (type == PIPE_INTERRUPT) {
2754                 qh->usecs = NS_TO_US(usb_calc_bus_time(USB_SPEED_HIGH,
2755                                 is_input, 0,
2756                                 hb_mult(maxp) * max_packet(maxp)));
2757                 qh->start = NO_FRAME;
2758
2759                 if (urb->dev->speed == USB_SPEED_HIGH) {
2760                         qh->c_usecs = 0;
2761                         qh->gap_uf = 0;
2762
2763                         qh->period = urb->interval >> 3;
2764                         if (qh->period == 0 && urb->interval != 1) {
2765                                 /* NOTE interval 2 or 4 uframes could work.
2766                                  * But interval 1 scheduling is simpler, and
2767                                  * includes high bandwidth.
2768                                  */
2769                                 urb->interval = 1;
2770                         } else if (qh->period > fotg210->periodic_size) {
2771                                 qh->period = fotg210->periodic_size;
2772                                 urb->interval = qh->period << 3;
2773                         }
2774                 } else {
2775                         int think_time;
2776
2777                         /* gap is f(FS/LS transfer times) */
2778                         qh->gap_uf = 1 + usb_calc_bus_time(urb->dev->speed,
2779                                         is_input, 0, maxp) / (125 * 1000);
2780
2781                         /* FIXME this just approximates SPLIT/CSPLIT times */
2782                         if (is_input) {         /* SPLIT, gap, CSPLIT+DATA */
2783                                 qh->c_usecs = qh->usecs + HS_USECS(0);
2784                                 qh->usecs = HS_USECS(1);
2785                         } else {                /* SPLIT+DATA, gap, CSPLIT */
2786                                 qh->usecs += HS_USECS(1);
2787                                 qh->c_usecs = HS_USECS(0);
2788                         }
2789
2790                         think_time = tt ? tt->think_time : 0;
2791                         qh->tt_usecs = NS_TO_US(think_time +
2792                                         usb_calc_bus_time(urb->dev->speed,
2793                                         is_input, 0, max_packet(maxp)));
2794                         qh->period = urb->interval;
2795                         if (qh->period > fotg210->periodic_size) {
2796                                 qh->period = fotg210->periodic_size;
2797                                 urb->interval = qh->period;
2798                         }
2799                 }
2800         }
2801
2802         /* support for tt scheduling, and access to toggles */
2803         qh->dev = urb->dev;
2804
2805         /* using TT? */
2806         switch (urb->dev->speed) {
2807         case USB_SPEED_LOW:
2808                 info1 |= QH_LOW_SPEED;
2809                 fallthrough;
2810
2811         case USB_SPEED_FULL:
2812                 /* EPS 0 means "full" */
2813                 if (type != PIPE_INTERRUPT)
2814                         info1 |= (FOTG210_TUNE_RL_TT << 28);
2815                 if (type == PIPE_CONTROL) {
2816                         info1 |= QH_CONTROL_EP;         /* for TT */
2817                         info1 |= QH_TOGGLE_CTL;         /* toggle from qtd */
2818                 }
2819                 info1 |= maxp << 16;
2820
2821                 info2 |= (FOTG210_TUNE_MULT_TT << 30);
2822
2823                 /* Some Freescale processors have an erratum in which the
2824                  * port number in the queue head was 0..N-1 instead of 1..N.
2825                  */
2826                 if (fotg210_has_fsl_portno_bug(fotg210))
2827                         info2 |= (urb->dev->ttport-1) << 23;
2828                 else
2829                         info2 |= urb->dev->ttport << 23;
2830
2831                 /* set the address of the TT; for TDI's integrated
2832                  * root hub tt, leave it zeroed.
2833                  */
2834                 if (tt && tt->hub != fotg210_to_hcd(fotg210)->self.root_hub)
2835                         info2 |= tt->hub->devnum << 16;
2836
2837                 /* NOTE:  if (PIPE_INTERRUPT) { scheduler sets c-mask } */
2838
2839                 break;
2840
2841         case USB_SPEED_HIGH:            /* no TT involved */
2842                 info1 |= QH_HIGH_SPEED;
2843                 if (type == PIPE_CONTROL) {
2844                         info1 |= (FOTG210_TUNE_RL_HS << 28);
2845                         info1 |= 64 << 16;      /* usb2 fixed maxpacket */
2846                         info1 |= QH_TOGGLE_CTL; /* toggle from qtd */
2847                         info2 |= (FOTG210_TUNE_MULT_HS << 30);
2848                 } else if (type == PIPE_BULK) {
2849                         info1 |= (FOTG210_TUNE_RL_HS << 28);
2850                         /* The USB spec says that high speed bulk endpoints
2851                          * always use 512 byte maxpacket.  But some device
2852                          * vendors decided to ignore that, and MSFT is happy
2853                          * to help them do so.  So now people expect to use
2854                          * such nonconformant devices with Linux too; sigh.
2855                          */
2856                         info1 |= max_packet(maxp) << 16;
2857                         info2 |= (FOTG210_TUNE_MULT_HS << 30);
2858                 } else {                /* PIPE_INTERRUPT */
2859                         info1 |= max_packet(maxp) << 16;
2860                         info2 |= hb_mult(maxp) << 30;
2861                 }
2862                 break;
2863         default:
2864                 fotg210_dbg(fotg210, "bogus dev %p speed %d\n", urb->dev,
2865                                 urb->dev->speed);
2866 done:
2867                 qh_destroy(fotg210, qh);
2868                 return NULL;
2869         }
2870
2871         /* NOTE:  if (PIPE_INTERRUPT) { scheduler sets s-mask } */
2872
2873         /* init as live, toggle clear, advance to dummy */
2874         qh->qh_state = QH_STATE_IDLE;
2875         hw = qh->hw;
2876         hw->hw_info1 = cpu_to_hc32(fotg210, info1);
2877         hw->hw_info2 = cpu_to_hc32(fotg210, info2);
2878         qh->is_out = !is_input;
2879         usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe), !is_input, 1);
2880         qh_refresh(fotg210, qh);
2881         return qh;
2882 }
2883
2884 static void enable_async(struct fotg210_hcd *fotg210)
2885 {
2886         if (fotg210->async_count++)
2887                 return;
2888
2889         /* Stop waiting to turn off the async schedule */
2890         fotg210->enabled_hrtimer_events &= ~BIT(FOTG210_HRTIMER_DISABLE_ASYNC);
2891
2892         /* Don't start the schedule until ASS is 0 */
2893         fotg210_poll_ASS(fotg210);
2894         turn_on_io_watchdog(fotg210);
2895 }
2896
2897 static void disable_async(struct fotg210_hcd *fotg210)
2898 {
2899         if (--fotg210->async_count)
2900                 return;
2901
2902         /* The async schedule and async_unlink list are supposed to be empty */
2903         WARN_ON(fotg210->async->qh_next.qh || fotg210->async_unlink);
2904
2905         /* Don't turn off the schedule until ASS is 1 */
2906         fotg210_poll_ASS(fotg210);
2907 }
2908
2909 /* move qh (and its qtds) onto async queue; maybe enable queue.  */
2910
2911 static void qh_link_async(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
2912 {
2913         __hc32 dma = QH_NEXT(fotg210, qh->qh_dma);
2914         struct fotg210_qh *head;
2915
2916         /* Don't link a QH if there's a Clear-TT-Buffer pending */
2917         if (unlikely(qh->clearing_tt))
2918                 return;
2919
2920         WARN_ON(qh->qh_state != QH_STATE_IDLE);
2921
2922         /* clear halt and/or toggle; and maybe recover from silicon quirk */
2923         qh_refresh(fotg210, qh);
2924
2925         /* splice right after start */
2926         head = fotg210->async;
2927         qh->qh_next = head->qh_next;
2928         qh->hw->hw_next = head->hw->hw_next;
2929         wmb();
2930
2931         head->qh_next.qh = qh;
2932         head->hw->hw_next = dma;
2933
2934         qh->xacterrs = 0;
2935         qh->qh_state = QH_STATE_LINKED;
2936         /* qtd completions reported later by interrupt */
2937
2938         enable_async(fotg210);
2939 }
2940
2941 /* For control/bulk/interrupt, return QH with these TDs appended.
2942  * Allocates and initializes the QH if necessary.
2943  * Returns null if it can't allocate a QH it needs to.
2944  * If the QH has TDs (urbs) already, that's great.
2945  */
2946 static struct fotg210_qh *qh_append_tds(struct fotg210_hcd *fotg210,
2947                 struct urb *urb, struct list_head *qtd_list,
2948                 int epnum, void **ptr)
2949 {
2950         struct fotg210_qh *qh = NULL;
2951         __hc32 qh_addr_mask = cpu_to_hc32(fotg210, 0x7f);
2952
2953         qh = (struct fotg210_qh *) *ptr;
2954         if (unlikely(qh == NULL)) {
2955                 /* can't sleep here, we have fotg210->lock... */
2956                 qh = qh_make(fotg210, urb, GFP_ATOMIC);
2957                 *ptr = qh;
2958         }
2959         if (likely(qh != NULL)) {
2960                 struct fotg210_qtd *qtd;
2961
2962                 if (unlikely(list_empty(qtd_list)))
2963                         qtd = NULL;
2964                 else
2965                         qtd = list_entry(qtd_list->next, struct fotg210_qtd,
2966                                         qtd_list);
2967
2968                 /* control qh may need patching ... */
2969                 if (unlikely(epnum == 0)) {
2970                         /* usb_reset_device() briefly reverts to address 0 */
2971                         if (usb_pipedevice(urb->pipe) == 0)
2972                                 qh->hw->hw_info1 &= ~qh_addr_mask;
2973                 }
2974
2975                 /* just one way to queue requests: swap with the dummy qtd.
2976                  * only hc or qh_refresh() ever modify the overlay.
2977                  */
2978                 if (likely(qtd != NULL)) {
2979                         struct fotg210_qtd *dummy;
2980                         dma_addr_t dma;
2981                         __hc32 token;
2982
2983                         /* to avoid racing the HC, use the dummy td instead of
2984                          * the first td of our list (becomes new dummy).  both
2985                          * tds stay deactivated until we're done, when the
2986                          * HC is allowed to fetch the old dummy (4.10.2).
2987                          */
2988                         token = qtd->hw_token;
2989                         qtd->hw_token = HALT_BIT(fotg210);
2990
2991                         dummy = qh->dummy;
2992
2993                         dma = dummy->qtd_dma;
2994                         *dummy = *qtd;
2995                         dummy->qtd_dma = dma;
2996
2997                         list_del(&qtd->qtd_list);
2998                         list_add(&dummy->qtd_list, qtd_list);
2999                         list_splice_tail(qtd_list, &qh->qtd_list);
3000
3001                         fotg210_qtd_init(fotg210, qtd, qtd->qtd_dma);
3002                         qh->dummy = qtd;
3003
3004                         /* hc must see the new dummy at list end */
3005                         dma = qtd->qtd_dma;
3006                         qtd = list_entry(qh->qtd_list.prev,
3007                                         struct fotg210_qtd, qtd_list);
3008                         qtd->hw_next = QTD_NEXT(fotg210, dma);
3009
3010                         /* let the hc process these next qtds */
3011                         wmb();
3012                         dummy->hw_token = token;
3013
3014                         urb->hcpriv = qh;
3015                 }
3016         }
3017         return qh;
3018 }
3019
3020 static int submit_async(struct fotg210_hcd *fotg210, struct urb *urb,
3021                 struct list_head *qtd_list, gfp_t mem_flags)
3022 {
3023         int epnum;
3024         unsigned long flags;
3025         struct fotg210_qh *qh = NULL;
3026         int rc;
3027
3028         epnum = urb->ep->desc.bEndpointAddress;
3029
3030 #ifdef FOTG210_URB_TRACE
3031         {
3032                 struct fotg210_qtd *qtd;
3033
3034                 qtd = list_entry(qtd_list->next, struct fotg210_qtd, qtd_list);
3035                 fotg210_dbg(fotg210,
3036                                 "%s %s urb %p ep%d%s len %d, qtd %p [qh %p]\n",
3037                                 __func__, urb->dev->devpath, urb,
3038                                 epnum & 0x0f, (epnum & USB_DIR_IN)
3039                                         ? "in" : "out",
3040                                 urb->transfer_buffer_length,
3041                                 qtd, urb->ep->hcpriv);
3042         }
3043 #endif
3044
3045         spin_lock_irqsave(&fotg210->lock, flags);
3046         if (unlikely(!HCD_HW_ACCESSIBLE(fotg210_to_hcd(fotg210)))) {
3047                 rc = -ESHUTDOWN;
3048                 goto done;
3049         }
3050         rc = usb_hcd_link_urb_to_ep(fotg210_to_hcd(fotg210), urb);
3051         if (unlikely(rc))
3052                 goto done;
3053
3054         qh = qh_append_tds(fotg210, urb, qtd_list, epnum, &urb->ep->hcpriv);
3055         if (unlikely(qh == NULL)) {
3056                 usb_hcd_unlink_urb_from_ep(fotg210_to_hcd(fotg210), urb);
3057                 rc = -ENOMEM;
3058                 goto done;
3059         }
3060
3061         /* Control/bulk operations through TTs don't need scheduling,
3062          * the HC and TT handle it when the TT has a buffer ready.
3063          */
3064         if (likely(qh->qh_state == QH_STATE_IDLE))
3065                 qh_link_async(fotg210, qh);
3066 done:
3067         spin_unlock_irqrestore(&fotg210->lock, flags);
3068         if (unlikely(qh == NULL))
3069                 qtd_list_free(fotg210, urb, qtd_list);
3070         return rc;
3071 }
3072
3073 static void single_unlink_async(struct fotg210_hcd *fotg210,
3074                 struct fotg210_qh *qh)
3075 {
3076         struct fotg210_qh *prev;
3077
3078         /* Add to the end of the list of QHs waiting for the next IAAD */
3079         qh->qh_state = QH_STATE_UNLINK;
3080         if (fotg210->async_unlink)
3081                 fotg210->async_unlink_last->unlink_next = qh;
3082         else
3083                 fotg210->async_unlink = qh;
3084         fotg210->async_unlink_last = qh;
3085
3086         /* Unlink it from the schedule */
3087         prev = fotg210->async;
3088         while (prev->qh_next.qh != qh)
3089                 prev = prev->qh_next.qh;
3090
3091         prev->hw->hw_next = qh->hw->hw_next;
3092         prev->qh_next = qh->qh_next;
3093         if (fotg210->qh_scan_next == qh)
3094                 fotg210->qh_scan_next = qh->qh_next.qh;
3095 }
3096
3097 static void start_iaa_cycle(struct fotg210_hcd *fotg210, bool nested)
3098 {
3099         /*
3100          * Do nothing if an IAA cycle is already running or
3101          * if one will be started shortly.
3102          */
3103         if (fotg210->async_iaa || fotg210->async_unlinking)
3104                 return;
3105
3106         /* Do all the waiting QHs at once */
3107         fotg210->async_iaa = fotg210->async_unlink;
3108         fotg210->async_unlink = NULL;
3109
3110         /* If the controller isn't running, we don't have to wait for it */
3111         if (unlikely(fotg210->rh_state < FOTG210_RH_RUNNING)) {
3112                 if (!nested)            /* Avoid recursion */
3113                         end_unlink_async(fotg210);
3114
3115         /* Otherwise start a new IAA cycle */
3116         } else if (likely(fotg210->rh_state == FOTG210_RH_RUNNING)) {
3117                 /* Make sure the unlinks are all visible to the hardware */
3118                 wmb();
3119
3120                 fotg210_writel(fotg210, fotg210->command | CMD_IAAD,
3121                                 &fotg210->regs->command);
3122                 fotg210_readl(fotg210, &fotg210->regs->command);
3123                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_IAA_WATCHDOG,
3124                                 true);
3125         }
3126 }
3127
3128 /* the async qh for the qtds being unlinked are now gone from the HC */
3129
3130 static void end_unlink_async(struct fotg210_hcd *fotg210)
3131 {
3132         struct fotg210_qh *qh;
3133
3134         /* Process the idle QHs */
3135 restart:
3136         fotg210->async_unlinking = true;
3137         while (fotg210->async_iaa) {
3138                 qh = fotg210->async_iaa;
3139                 fotg210->async_iaa = qh->unlink_next;
3140                 qh->unlink_next = NULL;
3141
3142                 qh->qh_state = QH_STATE_IDLE;
3143                 qh->qh_next.qh = NULL;
3144
3145                 qh_completions(fotg210, qh);
3146                 if (!list_empty(&qh->qtd_list) &&
3147                                 fotg210->rh_state == FOTG210_RH_RUNNING)
3148                         qh_link_async(fotg210, qh);
3149                 disable_async(fotg210);
3150         }
3151         fotg210->async_unlinking = false;
3152
3153         /* Start a new IAA cycle if any QHs are waiting for it */
3154         if (fotg210->async_unlink) {
3155                 start_iaa_cycle(fotg210, true);
3156                 if (unlikely(fotg210->rh_state < FOTG210_RH_RUNNING))
3157                         goto restart;
3158         }
3159 }
3160
3161 static void unlink_empty_async(struct fotg210_hcd *fotg210)
3162 {
3163         struct fotg210_qh *qh, *next;
3164         bool stopped = (fotg210->rh_state < FOTG210_RH_RUNNING);
3165         bool check_unlinks_later = false;
3166
3167         /* Unlink all the async QHs that have been empty for a timer cycle */
3168         next = fotg210->async->qh_next.qh;
3169         while (next) {
3170                 qh = next;
3171                 next = qh->qh_next.qh;
3172
3173                 if (list_empty(&qh->qtd_list) &&
3174                                 qh->qh_state == QH_STATE_LINKED) {
3175                         if (!stopped && qh->unlink_cycle ==
3176                                         fotg210->async_unlink_cycle)
3177                                 check_unlinks_later = true;
3178                         else
3179                                 single_unlink_async(fotg210, qh);
3180                 }
3181         }
3182
3183         /* Start a new IAA cycle if any QHs are waiting for it */
3184         if (fotg210->async_unlink)
3185                 start_iaa_cycle(fotg210, false);
3186
3187         /* QHs that haven't been empty for long enough will be handled later */
3188         if (check_unlinks_later) {
3189                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_ASYNC_UNLINKS,
3190                                 true);
3191                 ++fotg210->async_unlink_cycle;
3192         }
3193 }
3194
3195 /* makes sure the async qh will become idle */
3196 /* caller must own fotg210->lock */
3197
3198 static void start_unlink_async(struct fotg210_hcd *fotg210,
3199                 struct fotg210_qh *qh)
3200 {
3201         /*
3202          * If the QH isn't linked then there's nothing we can do
3203          * unless we were called during a giveback, in which case
3204          * qh_completions() has to deal with it.
3205          */
3206         if (qh->qh_state != QH_STATE_LINKED) {
3207                 if (qh->qh_state == QH_STATE_COMPLETING)
3208                         qh->needs_rescan = 1;
3209                 return;
3210         }
3211
3212         single_unlink_async(fotg210, qh);
3213         start_iaa_cycle(fotg210, false);
3214 }
3215
3216 static void scan_async(struct fotg210_hcd *fotg210)
3217 {
3218         struct fotg210_qh *qh;
3219         bool check_unlinks_later = false;
3220
3221         fotg210->qh_scan_next = fotg210->async->qh_next.qh;
3222         while (fotg210->qh_scan_next) {
3223                 qh = fotg210->qh_scan_next;
3224                 fotg210->qh_scan_next = qh->qh_next.qh;
3225 rescan:
3226                 /* clean any finished work for this qh */
3227                 if (!list_empty(&qh->qtd_list)) {
3228                         int temp;
3229
3230                         /*
3231                          * Unlinks could happen here; completion reporting
3232                          * drops the lock.  That's why fotg210->qh_scan_next
3233                          * always holds the next qh to scan; if the next qh
3234                          * gets unlinked then fotg210->qh_scan_next is adjusted
3235                          * in single_unlink_async().
3236                          */
3237                         temp = qh_completions(fotg210, qh);
3238                         if (qh->needs_rescan) {
3239                                 start_unlink_async(fotg210, qh);
3240                         } else if (list_empty(&qh->qtd_list)
3241                                         && qh->qh_state == QH_STATE_LINKED) {
3242                                 qh->unlink_cycle = fotg210->async_unlink_cycle;
3243                                 check_unlinks_later = true;
3244                         } else if (temp != 0)
3245                                 goto rescan;
3246                 }
3247         }
3248
3249         /*
3250          * Unlink empty entries, reducing DMA usage as well
3251          * as HCD schedule-scanning costs.  Delay for any qh
3252          * we just scanned, there's a not-unusual case that it
3253          * doesn't stay idle for long.
3254          */
3255         if (check_unlinks_later && fotg210->rh_state == FOTG210_RH_RUNNING &&
3256                         !(fotg210->enabled_hrtimer_events &
3257                         BIT(FOTG210_HRTIMER_ASYNC_UNLINKS))) {
3258                 fotg210_enable_event(fotg210,
3259                                 FOTG210_HRTIMER_ASYNC_UNLINKS, true);
3260                 ++fotg210->async_unlink_cycle;
3261         }
3262 }
3263 /* EHCI scheduled transaction support:  interrupt, iso, split iso
3264  * These are called "periodic" transactions in the EHCI spec.
3265  *
3266  * Note that for interrupt transfers, the QH/QTD manipulation is shared
3267  * with the "asynchronous" transaction support (control/bulk transfers).
3268  * The only real difference is in how interrupt transfers are scheduled.
3269  *
3270  * For ISO, we make an "iso_stream" head to serve the same role as a QH.
3271  * It keeps track of every ITD (or SITD) that's linked, and holds enough
3272  * pre-calculated schedule data to make appending to the queue be quick.
3273  */
3274 static int fotg210_get_frame(struct usb_hcd *hcd);
3275
3276 /* periodic_next_shadow - return "next" pointer on shadow list
3277  * @periodic: host pointer to qh/itd
3278  * @tag: hardware tag for type of this record
3279  */
3280 static union fotg210_shadow *periodic_next_shadow(struct fotg210_hcd *fotg210,
3281                 union fotg210_shadow *periodic, __hc32 tag)
3282 {
3283         switch (hc32_to_cpu(fotg210, tag)) {
3284         case Q_TYPE_QH:
3285                 return &periodic->qh->qh_next;
3286         case Q_TYPE_FSTN:
3287                 return &periodic->fstn->fstn_next;
3288         default:
3289                 return &periodic->itd->itd_next;
3290         }
3291 }
3292
3293 static __hc32 *shadow_next_periodic(struct fotg210_hcd *fotg210,
3294                 union fotg210_shadow *periodic, __hc32 tag)
3295 {
3296         switch (hc32_to_cpu(fotg210, tag)) {
3297         /* our fotg210_shadow.qh is actually software part */
3298         case Q_TYPE_QH:
3299                 return &periodic->qh->hw->hw_next;
3300         /* others are hw parts */
3301         default:
3302                 return periodic->hw_next;
3303         }
3304 }
3305
3306 /* caller must hold fotg210->lock */
3307 static void periodic_unlink(struct fotg210_hcd *fotg210, unsigned frame,
3308                 void *ptr)
3309 {
3310         union fotg210_shadow *prev_p = &fotg210->pshadow[frame];
3311         __hc32 *hw_p = &fotg210->periodic[frame];
3312         union fotg210_shadow here = *prev_p;
3313
3314         /* find predecessor of "ptr"; hw and shadow lists are in sync */
3315         while (here.ptr && here.ptr != ptr) {
3316                 prev_p = periodic_next_shadow(fotg210, prev_p,
3317                                 Q_NEXT_TYPE(fotg210, *hw_p));
3318                 hw_p = shadow_next_periodic(fotg210, &here,
3319                                 Q_NEXT_TYPE(fotg210, *hw_p));
3320                 here = *prev_p;
3321         }
3322         /* an interrupt entry (at list end) could have been shared */
3323         if (!here.ptr)
3324                 return;
3325
3326         /* update shadow and hardware lists ... the old "next" pointers
3327          * from ptr may still be in use, the caller updates them.
3328          */
3329         *prev_p = *periodic_next_shadow(fotg210, &here,
3330                         Q_NEXT_TYPE(fotg210, *hw_p));
3331
3332         *hw_p = *shadow_next_periodic(fotg210, &here,
3333                         Q_NEXT_TYPE(fotg210, *hw_p));
3334 }
3335
3336 /* how many of the uframe's 125 usecs are allocated? */
3337 static unsigned short periodic_usecs(struct fotg210_hcd *fotg210,
3338                 unsigned frame, unsigned uframe)
3339 {
3340         __hc32 *hw_p = &fotg210->periodic[frame];
3341         union fotg210_shadow *q = &fotg210->pshadow[frame];
3342         unsigned usecs = 0;
3343         struct fotg210_qh_hw *hw;
3344
3345         while (q->ptr) {
3346                 switch (hc32_to_cpu(fotg210, Q_NEXT_TYPE(fotg210, *hw_p))) {
3347                 case Q_TYPE_QH:
3348                         hw = q->qh->hw;
3349                         /* is it in the S-mask? */
3350                         if (hw->hw_info2 & cpu_to_hc32(fotg210, 1 << uframe))
3351                                 usecs += q->qh->usecs;
3352                         /* ... or C-mask? */
3353                         if (hw->hw_info2 & cpu_to_hc32(fotg210,
3354                                         1 << (8 + uframe)))
3355                                 usecs += q->qh->c_usecs;
3356                         hw_p = &hw->hw_next;
3357                         q = &q->qh->qh_next;
3358                         break;
3359                 /* case Q_TYPE_FSTN: */
3360                 default:
3361                         /* for "save place" FSTNs, count the relevant INTR
3362                          * bandwidth from the previous frame
3363                          */
3364                         if (q->fstn->hw_prev != FOTG210_LIST_END(fotg210))
3365                                 fotg210_dbg(fotg210, "ignoring FSTN cost ...\n");
3366
3367                         hw_p = &q->fstn->hw_next;
3368                         q = &q->fstn->fstn_next;
3369                         break;
3370                 case Q_TYPE_ITD:
3371                         if (q->itd->hw_transaction[uframe])
3372                                 usecs += q->itd->stream->usecs;
3373                         hw_p = &q->itd->hw_next;
3374                         q = &q->itd->itd_next;
3375                         break;
3376                 }
3377         }
3378         if (usecs > fotg210->uframe_periodic_max)
3379                 fotg210_err(fotg210, "uframe %d sched overrun: %d usecs\n",
3380                                 frame * 8 + uframe, usecs);
3381         return usecs;
3382 }
3383
3384 static int same_tt(struct usb_device *dev1, struct usb_device *dev2)
3385 {
3386         if (!dev1->tt || !dev2->tt)
3387                 return 0;
3388         if (dev1->tt != dev2->tt)
3389                 return 0;
3390         if (dev1->tt->multi)
3391                 return dev1->ttport == dev2->ttport;
3392         else
3393                 return 1;
3394 }
3395
3396 /* return true iff the device's transaction translator is available
3397  * for a periodic transfer starting at the specified frame, using
3398  * all the uframes in the mask.
3399  */
3400 static int tt_no_collision(struct fotg210_hcd *fotg210, unsigned period,
3401                 struct usb_device *dev, unsigned frame, u32 uf_mask)
3402 {
3403         if (period == 0)        /* error */
3404                 return 0;
3405
3406         /* note bandwidth wastage:  split never follows csplit
3407          * (different dev or endpoint) until the next uframe.
3408          * calling convention doesn't make that distinction.
3409          */
3410         for (; frame < fotg210->periodic_size; frame += period) {
3411                 union fotg210_shadow here;
3412                 __hc32 type;
3413                 struct fotg210_qh_hw *hw;
3414
3415                 here = fotg210->pshadow[frame];
3416                 type = Q_NEXT_TYPE(fotg210, fotg210->periodic[frame]);
3417                 while (here.ptr) {
3418                         switch (hc32_to_cpu(fotg210, type)) {
3419                         case Q_TYPE_ITD:
3420                                 type = Q_NEXT_TYPE(fotg210, here.itd->hw_next);
3421                                 here = here.itd->itd_next;
3422                                 continue;
3423                         case Q_TYPE_QH:
3424                                 hw = here.qh->hw;
3425                                 if (same_tt(dev, here.qh->dev)) {
3426                                         u32 mask;
3427
3428                                         mask = hc32_to_cpu(fotg210,
3429                                                         hw->hw_info2);
3430                                         /* "knows" no gap is needed */
3431                                         mask |= mask >> 8;
3432                                         if (mask & uf_mask)
3433                                                 break;
3434                                 }
3435                                 type = Q_NEXT_TYPE(fotg210, hw->hw_next);
3436                                 here = here.qh->qh_next;
3437                                 continue;
3438                         /* case Q_TYPE_FSTN: */
3439                         default:
3440                                 fotg210_dbg(fotg210,
3441                                                 "periodic frame %d bogus type %d\n",
3442                                                 frame, type);
3443                         }
3444
3445                         /* collision or error */
3446                         return 0;
3447                 }
3448         }
3449
3450         /* no collision */
3451         return 1;
3452 }
3453
3454 static void enable_periodic(struct fotg210_hcd *fotg210)
3455 {
3456         if (fotg210->periodic_count++)
3457                 return;
3458
3459         /* Stop waiting to turn off the periodic schedule */
3460         fotg210->enabled_hrtimer_events &=
3461                 ~BIT(FOTG210_HRTIMER_DISABLE_PERIODIC);
3462
3463         /* Don't start the schedule until PSS is 0 */
3464         fotg210_poll_PSS(fotg210);
3465         turn_on_io_watchdog(fotg210);
3466 }
3467
3468 static void disable_periodic(struct fotg210_hcd *fotg210)
3469 {
3470         if (--fotg210->periodic_count)
3471                 return;
3472
3473         /* Don't turn off the schedule until PSS is 1 */
3474         fotg210_poll_PSS(fotg210);
3475 }
3476
3477 /* periodic schedule slots have iso tds (normal or split) first, then a
3478  * sparse tree for active interrupt transfers.
3479  *
3480  * this just links in a qh; caller guarantees uframe masks are set right.
3481  * no FSTN support (yet; fotg210 0.96+)
3482  */
3483 static void qh_link_periodic(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
3484 {
3485         unsigned i;
3486         unsigned period = qh->period;
3487
3488         dev_dbg(&qh->dev->dev,
3489                         "link qh%d-%04x/%p start %d [%d/%d us]\n", period,
3490                         hc32_to_cpup(fotg210, &qh->hw->hw_info2) &
3491                         (QH_CMASK | QH_SMASK), qh, qh->start, qh->usecs,
3492                         qh->c_usecs);
3493
3494         /* high bandwidth, or otherwise every microframe */
3495         if (period == 0)
3496                 period = 1;
3497
3498         for (i = qh->start; i < fotg210->periodic_size; i += period) {
3499                 union fotg210_shadow *prev = &fotg210->pshadow[i];
3500                 __hc32 *hw_p = &fotg210->periodic[i];
3501                 union fotg210_shadow here = *prev;
3502                 __hc32 type = 0;
3503
3504                 /* skip the iso nodes at list head */
3505                 while (here.ptr) {
3506                         type = Q_NEXT_TYPE(fotg210, *hw_p);
3507                         if (type == cpu_to_hc32(fotg210, Q_TYPE_QH))
3508                                 break;
3509                         prev = periodic_next_shadow(fotg210, prev, type);
3510                         hw_p = shadow_next_periodic(fotg210, &here, type);
3511                         here = *prev;
3512                 }
3513
3514                 /* sorting each branch by period (slow-->fast)
3515                  * enables sharing interior tree nodes
3516                  */
3517                 while (here.ptr && qh != here.qh) {
3518                         if (qh->period > here.qh->period)
3519                                 break;
3520                         prev = &here.qh->qh_next;
3521                         hw_p = &here.qh->hw->hw_next;
3522                         here = *prev;
3523                 }
3524                 /* link in this qh, unless some earlier pass did that */
3525                 if (qh != here.qh) {
3526                         qh->qh_next = here;
3527                         if (here.qh)
3528                                 qh->hw->hw_next = *hw_p;
3529                         wmb();
3530                         prev->qh = qh;
3531                         *hw_p = QH_NEXT(fotg210, qh->qh_dma);
3532                 }
3533         }
3534         qh->qh_state = QH_STATE_LINKED;
3535         qh->xacterrs = 0;
3536
3537         /* update per-qh bandwidth for usbfs */
3538         fotg210_to_hcd(fotg210)->self.bandwidth_allocated += qh->period
3539                 ? ((qh->usecs + qh->c_usecs) / qh->period)
3540                 : (qh->usecs * 8);
3541
3542         list_add(&qh->intr_node, &fotg210->intr_qh_list);
3543
3544         /* maybe enable periodic schedule processing */
3545         ++fotg210->intr_count;
3546         enable_periodic(fotg210);
3547 }
3548
3549 static void qh_unlink_periodic(struct fotg210_hcd *fotg210,
3550                 struct fotg210_qh *qh)
3551 {
3552         unsigned i;
3553         unsigned period;
3554
3555         /*
3556          * If qh is for a low/full-speed device, simply unlinking it
3557          * could interfere with an ongoing split transaction.  To unlink
3558          * it safely would require setting the QH_INACTIVATE bit and
3559          * waiting at least one frame, as described in EHCI 4.12.2.5.
3560          *
3561          * We won't bother with any of this.  Instead, we assume that the
3562          * only reason for unlinking an interrupt QH while the current URB
3563          * is still active is to dequeue all the URBs (flush the whole
3564          * endpoint queue).
3565          *
3566          * If rebalancing the periodic schedule is ever implemented, this
3567          * approach will no longer be valid.
3568          */
3569
3570         /* high bandwidth, or otherwise part of every microframe */
3571         period = qh->period;
3572         if (!period)
3573                 period = 1;
3574
3575         for (i = qh->start; i < fotg210->periodic_size; i += period)
3576                 periodic_unlink(fotg210, i, qh);
3577
3578         /* update per-qh bandwidth for usbfs */
3579         fotg210_to_hcd(fotg210)->self.bandwidth_allocated -= qh->period
3580                 ? ((qh->usecs + qh->c_usecs) / qh->period)
3581                 : (qh->usecs * 8);
3582
3583         dev_dbg(&qh->dev->dev,
3584                         "unlink qh%d-%04x/%p start %d [%d/%d us]\n",
3585                         qh->period, hc32_to_cpup(fotg210, &qh->hw->hw_info2) &
3586                         (QH_CMASK | QH_SMASK), qh, qh->start, qh->usecs,
3587                         qh->c_usecs);
3588
3589         /* qh->qh_next still "live" to HC */
3590         qh->qh_state = QH_STATE_UNLINK;
3591         qh->qh_next.ptr = NULL;
3592
3593         if (fotg210->qh_scan_next == qh)
3594                 fotg210->qh_scan_next = list_entry(qh->intr_node.next,
3595                                 struct fotg210_qh, intr_node);
3596         list_del(&qh->intr_node);
3597 }
3598
3599 static void start_unlink_intr(struct fotg210_hcd *fotg210,
3600                 struct fotg210_qh *qh)
3601 {
3602         /* If the QH isn't linked then there's nothing we can do
3603          * unless we were called during a giveback, in which case
3604          * qh_completions() has to deal with it.
3605          */
3606         if (qh->qh_state != QH_STATE_LINKED) {
3607                 if (qh->qh_state == QH_STATE_COMPLETING)
3608                         qh->needs_rescan = 1;
3609                 return;
3610         }
3611
3612         qh_unlink_periodic(fotg210, qh);
3613
3614         /* Make sure the unlinks are visible before starting the timer */
3615         wmb();
3616
3617         /*
3618          * The EHCI spec doesn't say how long it takes the controller to
3619          * stop accessing an unlinked interrupt QH.  The timer delay is
3620          * 9 uframes; presumably that will be long enough.
3621          */
3622         qh->unlink_cycle = fotg210->intr_unlink_cycle;
3623
3624         /* New entries go at the end of the intr_unlink list */
3625         if (fotg210->intr_unlink)
3626                 fotg210->intr_unlink_last->unlink_next = qh;
3627         else
3628                 fotg210->intr_unlink = qh;
3629         fotg210->intr_unlink_last = qh;
3630
3631         if (fotg210->intr_unlinking)
3632                 ;       /* Avoid recursive calls */
3633         else if (fotg210->rh_state < FOTG210_RH_RUNNING)
3634                 fotg210_handle_intr_unlinks(fotg210);
3635         else if (fotg210->intr_unlink == qh) {
3636                 fotg210_enable_event(fotg210, FOTG210_HRTIMER_UNLINK_INTR,
3637                                 true);
3638                 ++fotg210->intr_unlink_cycle;
3639         }
3640 }
3641
3642 static void end_unlink_intr(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
3643 {
3644         struct fotg210_qh_hw *hw = qh->hw;
3645         int rc;
3646
3647         qh->qh_state = QH_STATE_IDLE;
3648         hw->hw_next = FOTG210_LIST_END(fotg210);
3649
3650         qh_completions(fotg210, qh);
3651
3652         /* reschedule QH iff another request is queued */
3653         if (!list_empty(&qh->qtd_list) &&
3654                         fotg210->rh_state == FOTG210_RH_RUNNING) {
3655                 rc = qh_schedule(fotg210, qh);
3656
3657                 /* An error here likely indicates handshake failure
3658                  * or no space left in the schedule.  Neither fault
3659                  * should happen often ...
3660                  *
3661                  * FIXME kill the now-dysfunctional queued urbs
3662                  */
3663                 if (rc != 0)
3664                         fotg210_err(fotg210, "can't reschedule qh %p, err %d\n",
3665                                         qh, rc);
3666         }
3667
3668         /* maybe turn off periodic schedule */
3669         --fotg210->intr_count;
3670         disable_periodic(fotg210);
3671 }
3672
3673 static int check_period(struct fotg210_hcd *fotg210, unsigned frame,
3674                 unsigned uframe, unsigned period, unsigned usecs)
3675 {
3676         int claimed;
3677
3678         /* complete split running into next frame?
3679          * given FSTN support, we could sometimes check...
3680          */
3681         if (uframe >= 8)
3682                 return 0;
3683
3684         /* convert "usecs we need" to "max already claimed" */
3685         usecs = fotg210->uframe_periodic_max - usecs;
3686
3687         /* we "know" 2 and 4 uframe intervals were rejected; so
3688          * for period 0, check _every_ microframe in the schedule.
3689          */
3690         if (unlikely(period == 0)) {
3691                 do {
3692                         for (uframe = 0; uframe < 7; uframe++) {
3693                                 claimed = periodic_usecs(fotg210, frame,
3694                                                 uframe);
3695                                 if (claimed > usecs)
3696                                         return 0;
3697                         }
3698                 } while ((frame += 1) < fotg210->periodic_size);
3699
3700         /* just check the specified uframe, at that period */
3701         } else {
3702                 do {
3703                         claimed = periodic_usecs(fotg210, frame, uframe);
3704                         if (claimed > usecs)
3705                                 return 0;
3706                 } while ((frame += period) < fotg210->periodic_size);
3707         }
3708
3709         /* success! */
3710         return 1;
3711 }
3712
3713 static int check_intr_schedule(struct fotg210_hcd *fotg210, unsigned frame,
3714                 unsigned uframe, const struct fotg210_qh *qh, __hc32 *c_maskp)
3715 {
3716         int retval = -ENOSPC;
3717         u8 mask = 0;
3718
3719         if (qh->c_usecs && uframe >= 6)         /* FSTN territory? */
3720                 goto done;
3721
3722         if (!check_period(fotg210, frame, uframe, qh->period, qh->usecs))
3723                 goto done;
3724         if (!qh->c_usecs) {
3725                 retval = 0;
3726                 *c_maskp = 0;
3727                 goto done;
3728         }
3729
3730         /* Make sure this tt's buffer is also available for CSPLITs.
3731          * We pessimize a bit; probably the typical full speed case
3732          * doesn't need the second CSPLIT.
3733          *
3734          * NOTE:  both SPLIT and CSPLIT could be checked in just
3735          * one smart pass...
3736          */
3737         mask = 0x03 << (uframe + qh->gap_uf);
3738         *c_maskp = cpu_to_hc32(fotg210, mask << 8);
3739
3740         mask |= 1 << uframe;
3741         if (tt_no_collision(fotg210, qh->period, qh->dev, frame, mask)) {
3742                 if (!check_period(fotg210, frame, uframe + qh->gap_uf + 1,
3743                                 qh->period, qh->c_usecs))
3744                         goto done;
3745                 if (!check_period(fotg210, frame, uframe + qh->gap_uf,
3746                                 qh->period, qh->c_usecs))
3747                         goto done;
3748                 retval = 0;
3749         }
3750 done:
3751         return retval;
3752 }
3753
3754 /* "first fit" scheduling policy used the first time through,
3755  * or when the previous schedule slot can't be re-used.
3756  */
3757 static int qh_schedule(struct fotg210_hcd *fotg210, struct fotg210_qh *qh)
3758 {
3759         int status;
3760         unsigned uframe;
3761         __hc32 c_mask;
3762         unsigned frame; /* 0..(qh->period - 1), or NO_FRAME */
3763         struct fotg210_qh_hw *hw = qh->hw;
3764
3765         qh_refresh(fotg210, qh);
3766         hw->hw_next = FOTG210_LIST_END(fotg210);
3767         frame = qh->start;
3768
3769         /* reuse the previous schedule slots, if we can */
3770         if (frame < qh->period) {
3771                 uframe = ffs(hc32_to_cpup(fotg210, &hw->hw_info2) & QH_SMASK);
3772                 status = check_intr_schedule(fotg210, frame, --uframe,
3773                                 qh, &c_mask);
3774         } else {
3775                 uframe = 0;
3776                 c_mask = 0;
3777                 status = -ENOSPC;
3778         }
3779
3780         /* else scan the schedule to find a group of slots such that all
3781          * uframes have enough periodic bandwidth available.
3782          */
3783         if (status) {
3784                 /* "normal" case, uframing flexible except with splits */
3785                 if (qh->period) {
3786                         int i;
3787
3788                         for (i = qh->period; status && i > 0; --i) {
3789                                 frame = ++fotg210->random_frame % qh->period;
3790                                 for (uframe = 0; uframe < 8; uframe++) {
3791                                         status = check_intr_schedule(fotg210,
3792                                                         frame, uframe, qh,
3793                                                         &c_mask);
3794                                         if (status == 0)
3795                                                 break;
3796                                 }
3797                         }
3798
3799                 /* qh->period == 0 means every uframe */
3800                 } else {
3801                         frame = 0;
3802                         status = check_intr_schedule(fotg210, 0, 0, qh,
3803                                         &c_mask);
3804                 }
3805                 if (status)
3806                         goto done;
3807                 qh->start = frame;
3808
3809                 /* reset S-frame and (maybe) C-frame masks */
3810                 hw->hw_info2 &= cpu_to_hc32(fotg210, ~(QH_CMASK | QH_SMASK));
3811                 hw->hw_info2 |= qh->period
3812                         ? cpu_to_hc32(fotg210, 1 << uframe)
3813                         : cpu_to_hc32(fotg210, QH_SMASK);
3814                 hw->hw_info2 |= c_mask;
3815         } else
3816                 fotg210_dbg(fotg210, "reused qh %p schedule\n", qh);
3817
3818         /* stuff into the periodic schedule */
3819         qh_link_periodic(fotg210, qh);
3820 done:
3821         return status;
3822 }
3823
3824 static int intr_submit(struct fotg210_hcd *fotg210, struct urb *urb,
3825                 struct list_head *qtd_list, gfp_t mem_flags)
3826 {
3827         unsigned epnum;
3828         unsigned long flags;
3829         struct fotg210_qh *qh;
3830         int status;
3831         struct list_head empty;
3832
3833         /* get endpoint and transfer/schedule data */
3834         epnum = urb->ep->desc.bEndpointAddress;
3835
3836         spin_lock_irqsave(&fotg210->lock, flags);
3837
3838         if (unlikely(!HCD_HW_ACCESSIBLE(fotg210_to_hcd(fotg210)))) {
3839                 status = -ESHUTDOWN;
3840                 goto done_not_linked;
3841         }
3842         status = usb_hcd_link_urb_to_ep(fotg210_to_hcd(fotg210), urb);
3843         if (unlikely(status))
3844                 goto done_not_linked;
3845
3846         /* get qh and force any scheduling errors */
3847         INIT_LIST_HEAD(&empty);
3848         qh = qh_append_tds(fotg210, urb, &empty, epnum, &urb->ep->hcpriv);
3849         if (qh == NULL) {
3850                 status = -ENOMEM;
3851                 goto done;
3852         }
3853         if (qh->qh_state == QH_STATE_IDLE) {
3854                 status = qh_schedule(fotg210, qh);
3855                 if (status)
3856                         goto done;
3857         }
3858
3859         /* then queue the urb's tds to the qh */
3860         qh = qh_append_tds(fotg210, urb, qtd_list, epnum, &urb->ep->hcpriv);
3861         BUG_ON(qh == NULL);
3862
3863         /* ... update usbfs periodic stats */
3864         fotg210_to_hcd(fotg210)->self.bandwidth_int_reqs++;
3865
3866 done:
3867         if (unlikely(status))
3868                 usb_hcd_unlink_urb_from_ep(fotg210_to_hcd(fotg210), urb);
3869 done_not_linked:
3870         spin_unlock_irqrestore(&fotg210->lock, flags);
3871         if (status)
3872                 qtd_list_free(fotg210, urb, qtd_list);
3873
3874         return status;
3875 }
3876
3877 static void scan_intr(struct fotg210_hcd *fotg210)
3878 {
3879         struct fotg210_qh *qh;
3880
3881         list_for_each_entry_safe(qh, fotg210->qh_scan_next,
3882                         &fotg210->intr_qh_list, intr_node) {
3883 rescan:
3884                 /* clean any finished work for this qh */
3885                 if (!list_empty(&qh->qtd_list)) {
3886                         int temp;
3887
3888                         /*
3889                          * Unlinks could happen here; completion reporting
3890                          * drops the lock.  That's why fotg210->qh_scan_next
3891                          * always holds the next qh to scan; if the next qh
3892                          * gets unlinked then fotg210->qh_scan_next is adjusted
3893                          * in qh_unlink_periodic().
3894                          */
3895                         temp = qh_completions(fotg210, qh);
3896                         if (unlikely(qh->needs_rescan ||
3897                                         (list_empty(&qh->qtd_list) &&
3898                                         qh->qh_state == QH_STATE_LINKED)))
3899                                 start_unlink_intr(fotg210, qh);
3900                         else if (temp != 0)
3901                                 goto rescan;
3902                 }
3903         }
3904 }
3905
3906 /* fotg210_iso_stream ops work with both ITD and SITD */
3907
3908 static struct fotg210_iso_stream *iso_stream_alloc(gfp_t mem_flags)
3909 {
3910         struct fotg210_iso_stream *stream;
3911
3912         stream = kzalloc(sizeof(*stream), mem_flags);
3913         if (likely(stream != NULL)) {
3914                 INIT_LIST_HEAD(&stream->td_list);
3915                 INIT_LIST_HEAD(&stream->free_list);
3916                 stream->next_uframe = -1;
3917         }
3918         return stream;
3919 }
3920
3921 static void iso_stream_init(struct fotg210_hcd *fotg210,
3922                 struct fotg210_iso_stream *stream, struct usb_device *dev,
3923                 int pipe, unsigned interval)
3924 {
3925         u32 buf1;
3926         unsigned epnum, maxp;
3927         int is_input;
3928         long bandwidth;
3929         unsigned multi;
3930
3931         /*
3932          * this might be a "high bandwidth" highspeed endpoint,
3933          * as encoded in the ep descriptor's wMaxPacket field
3934          */
3935         epnum = usb_pipeendpoint(pipe);
3936         is_input = usb_pipein(pipe) ? USB_DIR_IN : 0;
3937         maxp = usb_maxpacket(dev, pipe, !is_input);
3938         if (is_input)
3939                 buf1 = (1 << 11);
3940         else
3941                 buf1 = 0;
3942
3943         maxp = max_packet(maxp);
3944         multi = hb_mult(maxp);
3945         buf1 |= maxp;
3946         maxp *= multi;
3947
3948         stream->buf0 = cpu_to_hc32(fotg210, (epnum << 8) | dev->devnum);
3949         stream->buf1 = cpu_to_hc32(fotg210, buf1);
3950         stream->buf2 = cpu_to_hc32(fotg210, multi);
3951
3952         /* usbfs wants to report the average usecs per frame tied up
3953          * when transfers on this endpoint are scheduled ...
3954          */
3955         if (dev->speed == USB_SPEED_FULL) {
3956                 interval <<= 3;
3957                 stream->usecs = NS_TO_US(usb_calc_bus_time(dev->speed,
3958                                 is_input, 1, maxp));
3959                 stream->usecs /= 8;
3960         } else {
3961                 stream->highspeed = 1;
3962                 stream->usecs = HS_USECS_ISO(maxp);
3963         }
3964         bandwidth = stream->usecs * 8;
3965         bandwidth /= interval;
3966
3967         stream->bandwidth = bandwidth;
3968         stream->udev = dev;
3969         stream->bEndpointAddress = is_input | epnum;
3970         stream->interval = interval;
3971         stream->maxp = maxp;
3972 }
3973
3974 static struct fotg210_iso_stream *iso_stream_find(struct fotg210_hcd *fotg210,
3975                 struct urb *urb)
3976 {
3977         unsigned epnum;
3978         struct fotg210_iso_stream *stream;
3979         struct usb_host_endpoint *ep;
3980         unsigned long flags;
3981
3982         epnum = usb_pipeendpoint(urb->pipe);
3983         if (usb_pipein(urb->pipe))
3984                 ep = urb->dev->ep_in[epnum];
3985         else
3986                 ep = urb->dev->ep_out[epnum];
3987
3988         spin_lock_irqsave(&fotg210->lock, flags);
3989         stream = ep->hcpriv;
3990
3991         if (unlikely(stream == NULL)) {
3992                 stream = iso_stream_alloc(GFP_ATOMIC);
3993                 if (likely(stream != NULL)) {
3994                         ep->hcpriv = stream;
3995                         stream->ep = ep;
3996                         iso_stream_init(fotg210, stream, urb->dev, urb->pipe,
3997                                         urb->interval);
3998                 }
3999
4000         /* if dev->ep[epnum] is a QH, hw is set */
4001         } else if (unlikely(stream->hw != NULL)) {
4002                 fotg210_dbg(fotg210, "dev %s ep%d%s, not iso??\n",
4003                                 urb->dev->devpath, epnum,
4004                                 usb_pipein(urb->pipe) ? "in" : "out");
4005                 stream = NULL;
4006         }
4007
4008         spin_unlock_irqrestore(&fotg210->lock, flags);
4009         return stream;
4010 }
4011
4012 /* fotg210_iso_sched ops can be ITD-only or SITD-only */
4013
4014 static struct fotg210_iso_sched *iso_sched_alloc(unsigned packets,
4015                 gfp_t mem_flags)
4016 {
4017         struct fotg210_iso_sched *iso_sched;
4018         int size = sizeof(*iso_sched);
4019
4020         size += packets * sizeof(struct fotg210_iso_packet);
4021         iso_sched = kzalloc(size, mem_flags);
4022         if (likely(iso_sched != NULL))
4023                 INIT_LIST_HEAD(&iso_sched->td_list);
4024
4025         return iso_sched;
4026 }
4027
4028 static inline void itd_sched_init(struct fotg210_hcd *fotg210,
4029                 struct fotg210_iso_sched *iso_sched,
4030                 struct fotg210_iso_stream *stream, struct urb *urb)
4031 {
4032         unsigned i;
4033         dma_addr_t dma = urb->transfer_dma;
4034
4035         /* how many uframes are needed for these transfers */
4036         iso_sched->span = urb->number_of_packets * stream->interval;
4037
4038         /* figure out per-uframe itd fields that we'll need later
4039          * when we fit new itds into the schedule.
4040          */
4041         for (i = 0; i < urb->number_of_packets; i++) {
4042                 struct fotg210_iso_packet *uframe = &iso_sched->packet[i];
4043                 unsigned length;
4044                 dma_addr_t buf;
4045                 u32 trans;
4046
4047                 length = urb->iso_frame_desc[i].length;
4048                 buf = dma + urb->iso_frame_desc[i].offset;
4049
4050                 trans = FOTG210_ISOC_ACTIVE;
4051                 trans |= buf & 0x0fff;
4052                 if (unlikely(((i + 1) == urb->number_of_packets))
4053                                 && !(urb->transfer_flags & URB_NO_INTERRUPT))
4054                         trans |= FOTG210_ITD_IOC;
4055                 trans |= length << 16;
4056                 uframe->transaction = cpu_to_hc32(fotg210, trans);
4057
4058                 /* might need to cross a buffer page within a uframe */
4059                 uframe->bufp = (buf & ~(u64)0x0fff);
4060                 buf += length;
4061                 if (unlikely((uframe->bufp != (buf & ~(u64)0x0fff))))
4062                         uframe->cross = 1;
4063         }
4064 }
4065
4066 static void iso_sched_free(struct fotg210_iso_stream *stream,
4067                 struct fotg210_iso_sched *iso_sched)
4068 {
4069         if (!iso_sched)
4070                 return;
4071         /* caller must hold fotg210->lock!*/
4072         list_splice(&iso_sched->td_list, &stream->free_list);
4073         kfree(iso_sched);
4074 }
4075
4076 static int itd_urb_transaction(struct fotg210_iso_stream *stream,
4077                 struct fotg210_hcd *fotg210, struct urb *urb, gfp_t mem_flags)
4078 {
4079         struct fotg210_itd *itd;
4080         dma_addr_t itd_dma;
4081         int i;
4082         unsigned num_itds;
4083         struct fotg210_iso_sched *sched;
4084         unsigned long flags;
4085
4086         sched = iso_sched_alloc(urb->number_of_packets, mem_flags);
4087         if (unlikely(sched == NULL))
4088                 return -ENOMEM;
4089
4090         itd_sched_init(fotg210, sched, stream, urb);
4091
4092         if (urb->interval < 8)
4093                 num_itds = 1 + (sched->span + 7) / 8;
4094         else
4095                 num_itds = urb->number_of_packets;
4096
4097         /* allocate/init ITDs */
4098         spin_lock_irqsave(&fotg210->lock, flags);
4099         for (i = 0; i < num_itds; i++) {
4100
4101                 /*
4102                  * Use iTDs from the free list, but not iTDs that may
4103                  * still be in use by the hardware.
4104                  */
4105                 if (likely(!list_empty(&stream->free_list))) {
4106                         itd = list_first_entry(&stream->free_list,
4107                                         struct fotg210_itd, itd_list);
4108                         if (itd->frame == fotg210->now_frame)
4109                                 goto alloc_itd;
4110                         list_del(&itd->itd_list);
4111                         itd_dma = itd->itd_dma;
4112                 } else {
4113 alloc_itd:
4114                         spin_unlock_irqrestore(&fotg210->lock, flags);
4115                         itd = dma_pool_zalloc(fotg210->itd_pool, mem_flags,
4116                                         &itd_dma);
4117                         spin_lock_irqsave(&fotg210->lock, flags);
4118                         if (!itd) {
4119                                 iso_sched_free(stream, sched);
4120                                 spin_unlock_irqrestore(&fotg210->lock, flags);
4121                                 return -ENOMEM;
4122                         }
4123                 }
4124
4125                 itd->itd_dma = itd_dma;
4126                 list_add(&itd->itd_list, &sched->td_list);
4127         }
4128         spin_unlock_irqrestore(&fotg210->lock, flags);
4129
4130         /* temporarily store schedule info in hcpriv */
4131         urb->hcpriv = sched;
4132         urb->error_count = 0;
4133         return 0;
4134 }
4135
4136 static inline int itd_slot_ok(struct fotg210_hcd *fotg210, u32 mod, u32 uframe,
4137                 u8 usecs, u32 period)
4138 {
4139         uframe %= period;
4140         do {
4141                 /* can't commit more than uframe_periodic_max usec */
4142                 if (periodic_usecs(fotg210, uframe >> 3, uframe & 0x7)
4143                                 > (fotg210->uframe_periodic_max - usecs))
4144                         return 0;
4145
4146                 /* we know urb->interval is 2^N uframes */
4147                 uframe += period;
4148         } while (uframe < mod);
4149         return 1;
4150 }
4151
4152 /* This scheduler plans almost as far into the future as it has actual
4153  * periodic schedule slots.  (Affected by TUNE_FLS, which defaults to
4154  * "as small as possible" to be cache-friendlier.)  That limits the size
4155  * transfers you can stream reliably; avoid more than 64 msec per urb.
4156  * Also avoid queue depths of less than fotg210's worst irq latency (affected
4157  * by the per-urb URB_NO_INTERRUPT hint, the log2_irq_thresh module parameter,
4158  * and other factors); or more than about 230 msec total (for portability,
4159  * given FOTG210_TUNE_FLS and the slop).  Or, write a smarter scheduler!
4160  */
4161
4162 #define SCHEDULE_SLOP 80 /* microframes */
4163
4164 static int iso_stream_schedule(struct fotg210_hcd *fotg210, struct urb *urb,
4165                 struct fotg210_iso_stream *stream)
4166 {
4167         u32 now, next, start, period, span;
4168         int status;
4169         unsigned mod = fotg210->periodic_size << 3;
4170         struct fotg210_iso_sched *sched = urb->hcpriv;
4171
4172         period = urb->interval;
4173         span = sched->span;
4174
4175         if (span > mod - SCHEDULE_SLOP) {
4176                 fotg210_dbg(fotg210, "iso request %p too long\n", urb);
4177                 status = -EFBIG;
4178                 goto fail;
4179         }
4180
4181         now = fotg210_read_frame_index(fotg210) & (mod - 1);
4182
4183         /* Typical case: reuse current schedule, stream is still active.
4184          * Hopefully there are no gaps from the host falling behind
4185          * (irq delays etc), but if there are we'll take the next
4186          * slot in the schedule, implicitly assuming URB_ISO_ASAP.
4187          */
4188         if (likely(!list_empty(&stream->td_list))) {
4189                 u32 excess;
4190
4191                 /* For high speed devices, allow scheduling within the
4192                  * isochronous scheduling threshold.  For full speed devices
4193                  * and Intel PCI-based controllers, don't (work around for
4194                  * Intel ICH9 bug).
4195                  */
4196                 if (!stream->highspeed && fotg210->fs_i_thresh)
4197                         next = now + fotg210->i_thresh;
4198                 else
4199                         next = now;
4200
4201                 /* Fell behind (by up to twice the slop amount)?
4202                  * We decide based on the time of the last currently-scheduled
4203                  * slot, not the time of the next available slot.
4204                  */
4205                 excess = (stream->next_uframe - period - next) & (mod - 1);
4206                 if (excess >= mod - 2 * SCHEDULE_SLOP)
4207                         start = next + excess - mod + period *
4208                                         DIV_ROUND_UP(mod - excess, period);
4209                 else
4210                         start = next + excess + period;
4211                 if (start - now >= mod) {
4212                         fotg210_dbg(fotg210, "request %p would overflow (%d+%d >= %d)\n",
4213                                         urb, start - now - period, period,
4214                                         mod);
4215                         status = -EFBIG;
4216                         goto fail;
4217                 }
4218         }
4219
4220         /* need to schedule; when's the next (u)frame we could start?
4221          * this is bigger than fotg210->i_thresh allows; scheduling itself
4222          * isn't free, the slop should handle reasonably slow cpus.  it
4223          * can also help high bandwidth if the dma and irq loads don't
4224          * jump until after the queue is primed.
4225          */
4226         else {
4227                 int done = 0;
4228
4229                 start = SCHEDULE_SLOP + (now & ~0x07);
4230
4231                 /* NOTE:  assumes URB_ISO_ASAP, to limit complexity/bugs */
4232
4233                 /* find a uframe slot with enough bandwidth.
4234                  * Early uframes are more precious because full-speed
4235                  * iso IN transfers can't use late uframes,
4236                  * and therefore they should be allocated last.
4237                  */
4238                 next = start;
4239                 start += period;
4240                 do {
4241                         start--;
4242                         /* check schedule: enough space? */
4243                         if (itd_slot_ok(fotg210, mod, start,
4244                                         stream->usecs, period))
4245                                 done = 1;
4246                 } while (start > next && !done);
4247
4248                 /* no room in the schedule */
4249                 if (!done) {
4250                         fotg210_dbg(fotg210, "iso resched full %p (now %d max %d)\n",
4251                                         urb, now, now + mod);
4252                         status = -ENOSPC;
4253                         goto fail;
4254                 }
4255         }
4256
4257         /* Tried to schedule too far into the future? */
4258         if (unlikely(start - now + span - period >=
4259                         mod - 2 * SCHEDULE_SLOP)) {
4260                 fotg210_dbg(fotg210, "request %p would overflow (%d+%d >= %d)\n",
4261                                 urb, start - now, span - period,
4262                                 mod - 2 * SCHEDULE_SLOP);
4263                 status = -EFBIG;
4264                 goto fail;
4265         }
4266
4267         stream->next_uframe = start & (mod - 1);
4268
4269         /* report high speed start in uframes; full speed, in frames */
4270         urb->start_frame = stream->next_uframe;
4271         if (!stream->highspeed)
4272                 urb->start_frame >>= 3;
4273
4274         /* Make sure scan_isoc() sees these */
4275         if (fotg210->isoc_count == 0)
4276                 fotg210->next_frame = now >> 3;
4277         return 0;
4278
4279 fail:
4280         iso_sched_free(stream, sched);
4281         urb->hcpriv = NULL;
4282         return status;
4283 }
4284
4285 static inline void itd_init(struct fotg210_hcd *fotg210,
4286                 struct fotg210_iso_stream *stream, struct fotg210_itd *itd)
4287 {
4288         int i;
4289
4290         /* it's been recently zeroed */
4291         itd->hw_next = FOTG210_LIST_END(fotg210);
4292         itd->hw_bufp[0] = stream->buf0;
4293         itd->hw_bufp[1] = stream->buf1;
4294         itd->hw_bufp[2] = stream->buf2;
4295
4296         for (i = 0; i < 8; i++)
4297                 itd->index[i] = -1;
4298
4299         /* All other fields are filled when scheduling */
4300 }
4301
4302 static inline void itd_patch(struct fotg210_hcd *fotg210,
4303                 struct fotg210_itd *itd, struct fotg210_iso_sched *iso_sched,
4304                 unsigned index, u16 uframe)
4305 {
4306         struct fotg210_iso_packet *uf = &iso_sched->packet[index];
4307         unsigned pg = itd->pg;
4308
4309         uframe &= 0x07;
4310         itd->index[uframe] = index;
4311
4312         itd->hw_transaction[uframe] = uf->transaction;
4313         itd->hw_transaction[uframe] |= cpu_to_hc32(fotg210, pg << 12);
4314         itd->hw_bufp[pg] |= cpu_to_hc32(fotg210, uf->bufp & ~(u32)0);
4315         itd->hw_bufp_hi[pg] |= cpu_to_hc32(fotg210, (u32)(uf->bufp >> 32));
4316
4317         /* iso_frame_desc[].offset must be strictly increasing */
4318         if (unlikely(uf->cross)) {
4319                 u64 bufp = uf->bufp + 4096;
4320
4321                 itd->pg = ++pg;
4322                 itd->hw_bufp[pg] |= cpu_to_hc32(fotg210, bufp & ~(u32)0);
4323                 itd->hw_bufp_hi[pg] |= cpu_to_hc32(fotg210, (u32)(bufp >> 32));
4324         }
4325 }
4326
4327 static inline void itd_link(struct fotg210_hcd *fotg210, unsigned frame,
4328                 struct fotg210_itd *itd)
4329 {
4330         union fotg210_shadow *prev = &fotg210->pshadow[frame];
4331         __hc32 *hw_p = &fotg210->periodic[frame];
4332         union fotg210_shadow here = *prev;
4333         __hc32 type = 0;
4334
4335         /* skip any iso nodes which might belong to previous microframes */
4336         while (here.ptr) {
4337                 type = Q_NEXT_TYPE(fotg210, *hw_p);
4338                 if (type == cpu_to_hc32(fotg210, Q_TYPE_QH))
4339                         break;
4340                 prev = periodic_next_shadow(fotg210, prev, type);
4341                 hw_p = shadow_next_periodic(fotg210, &here, type);
4342                 here = *prev;
4343         }
4344
4345         itd->itd_next = here;
4346         itd->hw_next = *hw_p;
4347         prev->itd = itd;
4348         itd->frame = frame;
4349         wmb();
4350         *hw_p = cpu_to_hc32(fotg210, itd->itd_dma | Q_TYPE_ITD);
4351 }
4352
4353 /* fit urb's itds into the selected schedule slot; activate as needed */
4354 static void itd_link_urb(struct fotg210_hcd *fotg210, struct urb *urb,
4355                 unsigned mod, struct fotg210_iso_stream *stream)
4356 {
4357         int packet;
4358         unsigned next_uframe, uframe, frame;
4359         struct fotg210_iso_sched *iso_sched = urb->hcpriv;
4360         struct fotg210_itd *itd;
4361
4362         next_uframe = stream->next_uframe & (mod - 1);
4363
4364         if (unlikely(list_empty(&stream->td_list))) {
4365                 fotg210_to_hcd(fotg210)->self.bandwidth_allocated
4366                                 += stream->bandwidth;
4367                 fotg210_dbg(fotg210,
4368                         "schedule devp %s ep%d%s-iso period %d start %d.%d\n",
4369                         urb->dev->devpath, stream->bEndpointAddress & 0x0f,
4370                         (stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out",
4371                         urb->interval,
4372                         next_uframe >> 3, next_uframe & 0x7);
4373         }
4374
4375         /* fill iTDs uframe by uframe */
4376         for (packet = 0, itd = NULL; packet < urb->number_of_packets;) {
4377                 if (itd == NULL) {
4378                         /* ASSERT:  we have all necessary itds */
4379
4380                         /* ASSERT:  no itds for this endpoint in this uframe */
4381
4382                         itd = list_entry(iso_sched->td_list.next,
4383                                         struct fotg210_itd, itd_list);
4384                         list_move_tail(&itd->itd_list, &stream->td_list);
4385                         itd->stream = stream;
4386                         itd->urb = urb;
4387                         itd_init(fotg210, stream, itd);
4388                 }
4389
4390                 uframe = next_uframe & 0x07;
4391                 frame = next_uframe >> 3;
4392
4393                 itd_patch(fotg210, itd, iso_sched, packet, uframe);
4394
4395                 next_uframe += stream->interval;
4396                 next_uframe &= mod - 1;
4397                 packet++;
4398
4399                 /* link completed itds into the schedule */
4400                 if (((next_uframe >> 3) != frame)
4401                                 || packet == urb->number_of_packets) {
4402                         itd_link(fotg210, frame & (fotg210->periodic_size - 1),
4403                                         itd);
4404                         itd = NULL;
4405                 }
4406         }
4407         stream->next_uframe = next_uframe;
4408
4409         /* don't need that schedule data any more */
4410         iso_sched_free(stream, iso_sched);
4411         urb->hcpriv = NULL;
4412
4413         ++fotg210->isoc_count;
4414         enable_periodic(fotg210);
4415 }
4416
4417 #define ISO_ERRS (FOTG210_ISOC_BUF_ERR | FOTG210_ISOC_BABBLE |\
4418                 FOTG210_ISOC_XACTERR)
4419
4420 /* Process and recycle a completed ITD.  Return true iff its urb completed,
4421  * and hence its completion callback probably added things to the hardware
4422  * schedule.
4423  *
4424  * Note that we carefully avoid recycling this descriptor until after any
4425  * completion callback runs, so that it won't be reused quickly.  That is,
4426  * assuming (a) no more than two urbs per frame on this endpoint, and also
4427  * (b) only this endpoint's completions submit URBs.  It seems some silicon
4428  * corrupts things if you reuse completed descriptors very quickly...
4429  */
4430 static bool itd_complete(struct fotg210_hcd *fotg210, struct fotg210_itd *itd)
4431 {
4432         struct urb *urb = itd->urb;
4433         struct usb_iso_packet_descriptor *desc;
4434         u32 t;
4435         unsigned uframe;
4436         int urb_index = -1;
4437         struct fotg210_iso_stream *stream = itd->stream;
4438         struct usb_device *dev;
4439         bool retval = false;
4440
4441         /* for each uframe with a packet */
4442         for (uframe = 0; uframe < 8; uframe++) {
4443                 if (likely(itd->index[uframe] == -1))
4444                         continue;
4445                 urb_index = itd->index[uframe];
4446                 desc = &urb->iso_frame_desc[urb_index];
4447
4448                 t = hc32_to_cpup(fotg210, &itd->hw_transaction[uframe]);
4449                 itd->hw_transaction[uframe] = 0;
4450
4451                 /* report transfer status */
4452                 if (unlikely(t & ISO_ERRS)) {
4453                         urb->error_count++;
4454                         if (t & FOTG210_ISOC_BUF_ERR)
4455                                 desc->status = usb_pipein(urb->pipe)
4456                                         ? -ENOSR  /* hc couldn't read */
4457                                         : -ECOMM; /* hc couldn't write */
4458                         else if (t & FOTG210_ISOC_BABBLE)
4459                                 desc->status = -EOVERFLOW;
4460                         else /* (t & FOTG210_ISOC_XACTERR) */
4461                                 desc->status = -EPROTO;
4462
4463                         /* HC need not update length with this error */
4464                         if (!(t & FOTG210_ISOC_BABBLE)) {
4465                                 desc->actual_length =
4466                                         fotg210_itdlen(urb, desc, t);
4467                                 urb->actual_length += desc->actual_length;
4468                         }
4469                 } else if (likely((t & FOTG210_ISOC_ACTIVE) == 0)) {
4470                         desc->status = 0;
4471                         desc->actual_length = fotg210_itdlen(urb, desc, t);
4472                         urb->actual_length += desc->actual_length;
4473                 } else {
4474                         /* URB was too late */
4475                         desc->status = -EXDEV;
4476                 }
4477         }
4478
4479         /* handle completion now? */
4480         if (likely((urb_index + 1) != urb->number_of_packets))
4481                 goto done;
4482
4483         /* ASSERT: it's really the last itd for this urb
4484          * list_for_each_entry (itd, &stream->td_list, itd_list)
4485          *      BUG_ON (itd->urb == urb);
4486          */
4487
4488         /* give urb back to the driver; completion often (re)submits */
4489         dev = urb->dev;
4490         fotg210_urb_done(fotg210, urb, 0);
4491         retval = true;
4492         urb = NULL;
4493
4494         --fotg210->isoc_count;
4495         disable_periodic(fotg210);
4496
4497         if (unlikely(list_is_singular(&stream->td_list))) {
4498                 fotg210_to_hcd(fotg210)->self.bandwidth_allocated
4499                                 -= stream->bandwidth;
4500                 fotg210_dbg(fotg210,
4501                         "deschedule devp %s ep%d%s-iso\n",
4502                         dev->devpath, stream->bEndpointAddress & 0x0f,
4503                         (stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out");
4504         }
4505
4506 done:
4507         itd->urb = NULL;
4508
4509         /* Add to the end of the free list for later reuse */
4510         list_move_tail(&itd->itd_list, &stream->free_list);
4511
4512         /* Recycle the iTDs when the pipeline is empty (ep no longer in use) */
4513         if (list_empty(&stream->td_list)) {
4514                 list_splice_tail_init(&stream->free_list,
4515                                 &fotg210->cached_itd_list);
4516                 start_free_itds(fotg210);
4517         }
4518
4519         return retval;
4520 }
4521
4522 static int itd_submit(struct fotg210_hcd *fotg210, struct urb *urb,
4523                 gfp_t mem_flags)
4524 {
4525         int status = -EINVAL;
4526         unsigned long flags;
4527         struct fotg210_iso_stream *stream;
4528
4529         /* Get iso_stream head */
4530         stream = iso_stream_find(fotg210, urb);
4531         if (unlikely(stream == NULL)) {
4532                 fotg210_dbg(fotg210, "can't get iso stream\n");
4533                 return -ENOMEM;
4534         }
4535         if (unlikely(urb->interval != stream->interval &&
4536                         fotg210_port_speed(fotg210, 0) ==
4537                         USB_PORT_STAT_HIGH_SPEED)) {
4538                 fotg210_dbg(fotg210, "can't change iso interval %d --> %d\n",
4539                                 stream->interval, urb->interval);
4540                 goto done;
4541         }
4542
4543 #ifdef FOTG210_URB_TRACE
4544         fotg210_dbg(fotg210,
4545                         "%s %s urb %p ep%d%s len %d, %d pkts %d uframes[%p]\n",
4546                         __func__, urb->dev->devpath, urb,
4547                         usb_pipeendpoint(urb->pipe),
4548                         usb_pipein(urb->pipe) ? "in" : "out",
4549                         urb->transfer_buffer_length,
4550                         urb->number_of_packets, urb->interval,
4551                         stream);
4552 #endif
4553
4554         /* allocate ITDs w/o locking anything */
4555         status = itd_urb_transaction(stream, fotg210, urb, mem_flags);
4556         if (unlikely(status < 0)) {
4557                 fotg210_dbg(fotg210, "can't init itds\n");
4558                 goto done;
4559         }
4560
4561         /* schedule ... need to lock */
4562         spin_lock_irqsave(&fotg210->lock, flags);
4563         if (unlikely(!HCD_HW_ACCESSIBLE(fotg210_to_hcd(fotg210)))) {
4564                 status = -ESHUTDOWN;
4565                 goto done_not_linked;
4566         }
4567         status = usb_hcd_link_urb_to_ep(fotg210_to_hcd(fotg210), urb);
4568         if (unlikely(status))
4569                 goto done_not_linked;
4570         status = iso_stream_schedule(fotg210, urb, stream);
4571         if (likely(status == 0))
4572                 itd_link_urb(fotg210, urb, fotg210->periodic_size << 3, stream);
4573         else
4574                 usb_hcd_unlink_urb_from_ep(fotg210_to_hcd(fotg210), urb);
4575 done_not_linked:
4576         spin_unlock_irqrestore(&fotg210->lock, flags);
4577 done:
4578         return status;
4579 }
4580
4581 static inline int scan_frame_queue(struct fotg210_hcd *fotg210, unsigned frame,
4582                 unsigned now_frame, bool live)
4583 {
4584         unsigned uf;
4585         bool modified;
4586         union fotg210_shadow q, *q_p;
4587         __hc32 type, *hw_p;
4588
4589         /* scan each element in frame's queue for completions */
4590         q_p = &fotg210->pshadow[frame];
4591         hw_p = &fotg210->periodic[frame];
4592         q.ptr = q_p->ptr;
4593         type = Q_NEXT_TYPE(fotg210, *hw_p);
4594         modified = false;
4595
4596         while (q.ptr) {
4597                 switch (hc32_to_cpu(fotg210, type)) {
4598                 case Q_TYPE_ITD:
4599                         /* If this ITD is still active, leave it for
4600                          * later processing ... check the next entry.
4601                          * No need to check for activity unless the
4602                          * frame is current.
4603                          */
4604                         if (frame == now_frame && live) {
4605                                 rmb();
4606                                 for (uf = 0; uf < 8; uf++) {
4607                                         if (q.itd->hw_transaction[uf] &
4608                                                         ITD_ACTIVE(fotg210))
4609                                                 break;
4610                                 }
4611                                 if (uf < 8) {
4612                                         q_p = &q.itd->itd_next;
4613                                         hw_p = &q.itd->hw_next;
4614                                         type = Q_NEXT_TYPE(fotg210,
4615                                                         q.itd->hw_next);
4616                                         q = *q_p;
4617                                         break;
4618                                 }
4619                         }
4620
4621                         /* Take finished ITDs out of the schedule
4622                          * and process them:  recycle, maybe report
4623                          * URB completion.  HC won't cache the
4624                          * pointer for much longer, if at all.
4625                          */
4626                         *q_p = q.itd->itd_next;
4627                         *hw_p = q.itd->hw_next;
4628                         type = Q_NEXT_TYPE(fotg210, q.itd->hw_next);
4629                         wmb();
4630                         modified = itd_complete(fotg210, q.itd);
4631                         q = *q_p;
4632                         break;
4633                 default:
4634                         fotg210_dbg(fotg210, "corrupt type %d frame %d shadow %p\n",
4635                                         type, frame, q.ptr);
4636                         fallthrough;
4637                 case Q_TYPE_QH:
4638                 case Q_TYPE_FSTN:
4639                         /* End of the iTDs and siTDs */
4640                         q.ptr = NULL;
4641                         break;
4642                 }
4643
4644                 /* assume completion callbacks modify the queue */
4645                 if (unlikely(modified && fotg210->isoc_count > 0))
4646                         return -EINVAL;
4647         }
4648         return 0;
4649 }
4650
4651 static void scan_isoc(struct fotg210_hcd *fotg210)
4652 {
4653         unsigned uf, now_frame, frame, ret;
4654         unsigned fmask = fotg210->periodic_size - 1;
4655         bool live;
4656
4657         /*
4658          * When running, scan from last scan point up to "now"
4659          * else clean up by scanning everything that's left.
4660          * Touches as few pages as possible:  cache-friendly.
4661          */
4662         if (fotg210->rh_state >= FOTG210_RH_RUNNING) {
4663                 uf = fotg210_read_frame_index(fotg210);
4664                 now_frame = (uf >> 3) & fmask;
4665                 live = true;
4666         } else  {
4667                 now_frame = (fotg210->next_frame - 1) & fmask;
4668                 live = false;
4669         }
4670         fotg210->now_frame = now_frame;
4671
4672         frame = fotg210->next_frame;
4673         for (;;) {
4674                 ret = 1;
4675                 while (ret != 0)
4676                         ret = scan_frame_queue(fotg210, frame,
4677                                         now_frame, live);
4678
4679                 /* Stop when we have reached the current frame */
4680                 if (frame == now_frame)
4681                         break;
4682                 frame = (frame + 1) & fmask;
4683         }
4684         fotg210->next_frame = now_frame;
4685 }
4686
4687 /* Display / Set uframe_periodic_max
4688  */
4689 static ssize_t uframe_periodic_max_show(struct device *dev,
4690                 struct device_attribute *attr, char *buf)
4691 {
4692         struct fotg210_hcd *fotg210;
4693         int n;
4694
4695         fotg210 = hcd_to_fotg210(bus_to_hcd(dev_get_drvdata(dev)));
4696         n = scnprintf(buf, PAGE_SIZE, "%d\n", fotg210->uframe_periodic_max);
4697         return n;
4698 }
4699
4700
4701 static ssize_t uframe_periodic_max_store(struct device *dev,
4702                 struct device_attribute *attr, const char *buf, size_t count)
4703 {
4704         struct fotg210_hcd *fotg210;
4705         unsigned uframe_periodic_max;
4706         unsigned frame, uframe;
4707         unsigned short allocated_max;
4708         unsigned long flags;
4709         ssize_t ret;
4710
4711         fotg210 = hcd_to_fotg210(bus_to_hcd(dev_get_drvdata(dev)));
4712         if (kstrtouint(buf, 0, &uframe_periodic_max) < 0)
4713                 return -EINVAL;
4714
4715         if (uframe_periodic_max < 100 || uframe_periodic_max >= 125) {
4716                 fotg210_info(fotg210, "rejecting invalid request for uframe_periodic_max=%u\n",
4717                                 uframe_periodic_max);
4718                 return -EINVAL;
4719         }
4720
4721         ret = -EINVAL;
4722
4723         /*
4724          * lock, so that our checking does not race with possible periodic
4725          * bandwidth allocation through submitting new urbs.
4726          */
4727         spin_lock_irqsave(&fotg210->lock, flags);
4728
4729         /*
4730          * for request to decrease max periodic bandwidth, we have to check
4731          * every microframe in the schedule to see whether the decrease is
4732          * possible.
4733          */
4734         if (uframe_periodic_max < fotg210->uframe_periodic_max) {
4735                 allocated_max = 0;
4736
4737                 for (frame = 0; frame < fotg210->periodic_size; ++frame)
4738                         for (uframe = 0; uframe < 7; ++uframe)
4739                                 allocated_max = max(allocated_max,
4740                                                 periodic_usecs(fotg210, frame,
4741                                                 uframe));
4742
4743                 if (allocated_max > uframe_periodic_max) {
4744                         fotg210_info(fotg210,
4745                                         "cannot decrease uframe_periodic_max because periodic bandwidth is already allocated (%u > %u)\n",
4746                                         allocated_max, uframe_periodic_max);
4747                         goto out_unlock;
4748                 }
4749         }
4750
4751         /* increasing is always ok */
4752
4753         fotg210_info(fotg210,
4754                         "setting max periodic bandwidth to %u%% (== %u usec/uframe)\n",
4755                         100 * uframe_periodic_max/125, uframe_periodic_max);
4756
4757         if (uframe_periodic_max != 100)
4758                 fotg210_warn(fotg210, "max periodic bandwidth set is non-standard\n");
4759
4760         fotg210->uframe_periodic_max = uframe_periodic_max;
4761         ret = count;
4762
4763 out_unlock:
4764         spin_unlock_irqrestore(&fotg210->lock, flags);
4765         return ret;
4766 }
4767
4768 static DEVICE_ATTR_RW(uframe_periodic_max);
4769
4770 static inline int create_sysfs_files(struct fotg210_hcd *fotg210)
4771 {
4772         struct device *controller = fotg210_to_hcd(fotg210)->self.controller;
4773
4774         return device_create_file(controller, &dev_attr_uframe_periodic_max);
4775 }
4776
4777 static inline void remove_sysfs_files(struct fotg210_hcd *fotg210)
4778 {
4779         struct device *controller = fotg210_to_hcd(fotg210)->self.controller;
4780
4781         device_remove_file(controller, &dev_attr_uframe_periodic_max);
4782 }
4783 /* On some systems, leaving remote wakeup enabled prevents system shutdown.
4784  * The firmware seems to think that powering off is a wakeup event!
4785  * This routine turns off remote wakeup and everything else, on all ports.
4786  */
4787 static void fotg210_turn_off_all_ports(struct fotg210_hcd *fotg210)
4788 {
4789         u32 __iomem *status_reg = &fotg210->regs->port_status;
4790
4791         fotg210_writel(fotg210, PORT_RWC_BITS, status_reg);
4792 }
4793
4794 /* Halt HC, turn off all ports, and let the BIOS use the companion controllers.
4795  * Must be called with interrupts enabled and the lock not held.
4796  */
4797 static void fotg210_silence_controller(struct fotg210_hcd *fotg210)
4798 {
4799         fotg210_halt(fotg210);
4800
4801         spin_lock_irq(&fotg210->lock);
4802         fotg210->rh_state = FOTG210_RH_HALTED;
4803         fotg210_turn_off_all_ports(fotg210);
4804         spin_unlock_irq(&fotg210->lock);
4805 }
4806
4807 /* fotg210_shutdown kick in for silicon on any bus (not just pci, etc).
4808  * This forcibly disables dma and IRQs, helping kexec and other cases
4809  * where the next system software may expect clean state.
4810  */
4811 static void fotg210_shutdown(struct usb_hcd *hcd)
4812 {
4813         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
4814
4815         spin_lock_irq(&fotg210->lock);
4816         fotg210->shutdown = true;
4817         fotg210->rh_state = FOTG210_RH_STOPPING;
4818         fotg210->enabled_hrtimer_events = 0;
4819         spin_unlock_irq(&fotg210->lock);
4820
4821         fotg210_silence_controller(fotg210);
4822
4823         hrtimer_cancel(&fotg210->hrtimer);
4824 }
4825
4826 /* fotg210_work is called from some interrupts, timers, and so on.
4827  * it calls driver completion functions, after dropping fotg210->lock.
4828  */
4829 static void fotg210_work(struct fotg210_hcd *fotg210)
4830 {
4831         /* another CPU may drop fotg210->lock during a schedule scan while
4832          * it reports urb completions.  this flag guards against bogus
4833          * attempts at re-entrant schedule scanning.
4834          */
4835         if (fotg210->scanning) {
4836                 fotg210->need_rescan = true;
4837                 return;
4838         }
4839         fotg210->scanning = true;
4840
4841 rescan:
4842         fotg210->need_rescan = false;
4843         if (fotg210->async_count)
4844                 scan_async(fotg210);
4845         if (fotg210->intr_count > 0)
4846                 scan_intr(fotg210);
4847         if (fotg210->isoc_count > 0)
4848                 scan_isoc(fotg210);
4849         if (fotg210->need_rescan)
4850                 goto rescan;
4851         fotg210->scanning = false;
4852
4853         /* the IO watchdog guards against hardware or driver bugs that
4854          * misplace IRQs, and should let us run completely without IRQs.
4855          * such lossage has been observed on both VT6202 and VT8235.
4856          */
4857         turn_on_io_watchdog(fotg210);
4858 }
4859
4860 /* Called when the fotg210_hcd module is removed.
4861  */
4862 static void fotg210_stop(struct usb_hcd *hcd)
4863 {
4864         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
4865
4866         fotg210_dbg(fotg210, "stop\n");
4867
4868         /* no more interrupts ... */
4869
4870         spin_lock_irq(&fotg210->lock);
4871         fotg210->enabled_hrtimer_events = 0;
4872         spin_unlock_irq(&fotg210->lock);
4873
4874         fotg210_quiesce(fotg210);
4875         fotg210_silence_controller(fotg210);
4876         fotg210_reset(fotg210);
4877
4878         hrtimer_cancel(&fotg210->hrtimer);
4879         remove_sysfs_files(fotg210);
4880         remove_debug_files(fotg210);
4881
4882         /* root hub is shut down separately (first, when possible) */
4883         spin_lock_irq(&fotg210->lock);
4884         end_free_itds(fotg210);
4885         spin_unlock_irq(&fotg210->lock);
4886         fotg210_mem_cleanup(fotg210);
4887
4888 #ifdef FOTG210_STATS
4889         fotg210_dbg(fotg210, "irq normal %ld err %ld iaa %ld (lost %ld)\n",
4890                         fotg210->stats.normal, fotg210->stats.error,
4891                         fotg210->stats.iaa, fotg210->stats.lost_iaa);
4892         fotg210_dbg(fotg210, "complete %ld unlink %ld\n",
4893                         fotg210->stats.complete, fotg210->stats.unlink);
4894 #endif
4895
4896         dbg_status(fotg210, "fotg210_stop completed",
4897                         fotg210_readl(fotg210, &fotg210->regs->status));
4898 }
4899
4900 /* one-time init, only for memory state */
4901 static int hcd_fotg210_init(struct usb_hcd *hcd)
4902 {
4903         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
4904         u32 temp;
4905         int retval;
4906         u32 hcc_params;
4907         struct fotg210_qh_hw *hw;
4908
4909         spin_lock_init(&fotg210->lock);
4910
4911         /*
4912          * keep io watchdog by default, those good HCDs could turn off it later
4913          */
4914         fotg210->need_io_watchdog = 1;
4915
4916         hrtimer_init(&fotg210->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
4917         fotg210->hrtimer.function = fotg210_hrtimer_func;
4918         fotg210->next_hrtimer_event = FOTG210_HRTIMER_NO_EVENT;
4919
4920         hcc_params = fotg210_readl(fotg210, &fotg210->caps->hcc_params);
4921
4922         /*
4923          * by default set standard 80% (== 100 usec/uframe) max periodic
4924          * bandwidth as required by USB 2.0
4925          */
4926         fotg210->uframe_periodic_max = 100;
4927
4928         /*
4929          * hw default: 1K periodic list heads, one per frame.
4930          * periodic_size can shrink by USBCMD update if hcc_params allows.
4931          */
4932         fotg210->periodic_size = DEFAULT_I_TDPS;
4933         INIT_LIST_HEAD(&fotg210->intr_qh_list);
4934         INIT_LIST_HEAD(&fotg210->cached_itd_list);
4935
4936         if (HCC_PGM_FRAMELISTLEN(hcc_params)) {
4937                 /* periodic schedule size can be smaller than default */
4938                 switch (FOTG210_TUNE_FLS) {
4939                 case 0:
4940                         fotg210->periodic_size = 1024;
4941                         break;
4942                 case 1:
4943                         fotg210->periodic_size = 512;
4944                         break;
4945                 case 2:
4946                         fotg210->periodic_size = 256;
4947                         break;
4948                 default:
4949                         BUG();
4950                 }
4951         }
4952         retval = fotg210_mem_init(fotg210, GFP_KERNEL);
4953         if (retval < 0)
4954                 return retval;
4955
4956         /* controllers may cache some of the periodic schedule ... */
4957         fotg210->i_thresh = 2;
4958
4959         /*
4960          * dedicate a qh for the async ring head, since we couldn't unlink
4961          * a 'real' qh without stopping the async schedule [4.8].  use it
4962          * as the 'reclamation list head' too.
4963          * its dummy is used in hw_alt_next of many tds, to prevent the qh
4964          * from automatically advancing to the next td after short reads.
4965          */
4966         fotg210->async->qh_next.qh = NULL;
4967         hw = fotg210->async->hw;
4968         hw->hw_next = QH_NEXT(fotg210, fotg210->async->qh_dma);
4969         hw->hw_info1 = cpu_to_hc32(fotg210, QH_HEAD);
4970         hw->hw_token = cpu_to_hc32(fotg210, QTD_STS_HALT);
4971         hw->hw_qtd_next = FOTG210_LIST_END(fotg210);
4972         fotg210->async->qh_state = QH_STATE_LINKED;
4973         hw->hw_alt_next = QTD_NEXT(fotg210, fotg210->async->dummy->qtd_dma);
4974
4975         /* clear interrupt enables, set irq latency */
4976         if (log2_irq_thresh < 0 || log2_irq_thresh > 6)
4977                 log2_irq_thresh = 0;
4978         temp = 1 << (16 + log2_irq_thresh);
4979         if (HCC_CANPARK(hcc_params)) {
4980                 /* HW default park == 3, on hardware that supports it (like
4981                  * NVidia and ALI silicon), maximizes throughput on the async
4982                  * schedule by avoiding QH fetches between transfers.
4983                  *
4984                  * With fast usb storage devices and NForce2, "park" seems to
4985                  * make problems:  throughput reduction (!), data errors...
4986                  */
4987                 if (park) {
4988                         park = min_t(unsigned, park, 3);
4989                         temp |= CMD_PARK;
4990                         temp |= park << 8;
4991                 }
4992                 fotg210_dbg(fotg210, "park %d\n", park);
4993         }
4994         if (HCC_PGM_FRAMELISTLEN(hcc_params)) {
4995                 /* periodic schedule size can be smaller than default */
4996                 temp &= ~(3 << 2);
4997                 temp |= (FOTG210_TUNE_FLS << 2);
4998         }
4999         fotg210->command = temp;
5000
5001         /* Accept arbitrarily long scatter-gather lists */
5002         if (!hcd->localmem_pool)
5003                 hcd->self.sg_tablesize = ~0;
5004         return 0;
5005 }
5006
5007 /* start HC running; it's halted, hcd_fotg210_init() has been run (once) */
5008 static int fotg210_run(struct usb_hcd *hcd)
5009 {
5010         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5011         u32 temp;
5012
5013         hcd->uses_new_polling = 1;
5014
5015         /* EHCI spec section 4.1 */
5016
5017         fotg210_writel(fotg210, fotg210->periodic_dma,
5018                         &fotg210->regs->frame_list);
5019         fotg210_writel(fotg210, (u32)fotg210->async->qh_dma,
5020                         &fotg210->regs->async_next);
5021
5022         /*
5023          * hcc_params controls whether fotg210->regs->segment must (!!!)
5024          * be used; it constrains QH/ITD/SITD and QTD locations.
5025          * dma_pool consistent memory always uses segment zero.
5026          * streaming mappings for I/O buffers, like pci_map_single(),
5027          * can return segments above 4GB, if the device allows.
5028          *
5029          * NOTE:  the dma mask is visible through dev->dma_mask, so
5030          * drivers can pass this info along ... like NETIF_F_HIGHDMA,
5031          * Scsi_Host.highmem_io, and so forth.  It's readonly to all
5032          * host side drivers though.
5033          */
5034         fotg210_readl(fotg210, &fotg210->caps->hcc_params);
5035
5036         /*
5037          * Philips, Intel, and maybe others need CMD_RUN before the
5038          * root hub will detect new devices (why?); NEC doesn't
5039          */
5040         fotg210->command &= ~(CMD_IAAD|CMD_PSE|CMD_ASE|CMD_RESET);
5041         fotg210->command |= CMD_RUN;
5042         fotg210_writel(fotg210, fotg210->command, &fotg210->regs->command);
5043         dbg_cmd(fotg210, "init", fotg210->command);
5044
5045         /*
5046          * Start, enabling full USB 2.0 functionality ... usb 1.1 devices
5047          * are explicitly handed to companion controller(s), so no TT is
5048          * involved with the root hub.  (Except where one is integrated,
5049          * and there's no companion controller unless maybe for USB OTG.)
5050          *
5051          * Turning on the CF flag will transfer ownership of all ports
5052          * from the companions to the EHCI controller.  If any of the
5053          * companions are in the middle of a port reset at the time, it
5054          * could cause trouble.  Write-locking ehci_cf_port_reset_rwsem
5055          * guarantees that no resets are in progress.  After we set CF,
5056          * a short delay lets the hardware catch up; new resets shouldn't
5057          * be started before the port switching actions could complete.
5058          */
5059         down_write(&ehci_cf_port_reset_rwsem);
5060         fotg210->rh_state = FOTG210_RH_RUNNING;
5061         /* unblock posted writes */
5062         fotg210_readl(fotg210, &fotg210->regs->command);
5063         usleep_range(5000, 10000);
5064         up_write(&ehci_cf_port_reset_rwsem);
5065         fotg210->last_periodic_enable = ktime_get_real();
5066
5067         temp = HC_VERSION(fotg210,
5068                         fotg210_readl(fotg210, &fotg210->caps->hc_capbase));
5069         fotg210_info(fotg210,
5070                         "USB %x.%x started, EHCI %x.%02x\n",
5071                         ((fotg210->sbrn & 0xf0) >> 4), (fotg210->sbrn & 0x0f),
5072                         temp >> 8, temp & 0xff);
5073
5074         fotg210_writel(fotg210, INTR_MASK,
5075                         &fotg210->regs->intr_enable); /* Turn On Interrupts */
5076
5077         /* GRR this is run-once init(), being done every time the HC starts.
5078          * So long as they're part of class devices, we can't do it init()
5079          * since the class device isn't created that early.
5080          */
5081         create_debug_files(fotg210);
5082         create_sysfs_files(fotg210);
5083
5084         return 0;
5085 }
5086
5087 static int fotg210_setup(struct usb_hcd *hcd)
5088 {
5089         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5090         int retval;
5091
5092         fotg210->regs = (void __iomem *)fotg210->caps +
5093                         HC_LENGTH(fotg210,
5094                         fotg210_readl(fotg210, &fotg210->caps->hc_capbase));
5095         dbg_hcs_params(fotg210, "reset");
5096         dbg_hcc_params(fotg210, "reset");
5097
5098         /* cache this readonly data; minimize chip reads */
5099         fotg210->hcs_params = fotg210_readl(fotg210,
5100                         &fotg210->caps->hcs_params);
5101
5102         fotg210->sbrn = HCD_USB2;
5103
5104         /* data structure init */
5105         retval = hcd_fotg210_init(hcd);
5106         if (retval)
5107                 return retval;
5108
5109         retval = fotg210_halt(fotg210);
5110         if (retval)
5111                 return retval;
5112
5113         fotg210_reset(fotg210);
5114
5115         return 0;
5116 }
5117
5118 static irqreturn_t fotg210_irq(struct usb_hcd *hcd)
5119 {
5120         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5121         u32 status, masked_status, pcd_status = 0, cmd;
5122         int bh;
5123
5124         spin_lock(&fotg210->lock);
5125
5126         status = fotg210_readl(fotg210, &fotg210->regs->status);
5127
5128         /* e.g. cardbus physical eject */
5129         if (status == ~(u32) 0) {
5130                 fotg210_dbg(fotg210, "device removed\n");
5131                 goto dead;
5132         }
5133
5134         /*
5135          * We don't use STS_FLR, but some controllers don't like it to
5136          * remain on, so mask it out along with the other status bits.
5137          */
5138         masked_status = status & (INTR_MASK | STS_FLR);
5139
5140         /* Shared IRQ? */
5141         if (!masked_status ||
5142                         unlikely(fotg210->rh_state == FOTG210_RH_HALTED)) {
5143                 spin_unlock(&fotg210->lock);
5144                 return IRQ_NONE;
5145         }
5146
5147         /* clear (just) interrupts */
5148         fotg210_writel(fotg210, masked_status, &fotg210->regs->status);
5149         cmd = fotg210_readl(fotg210, &fotg210->regs->command);
5150         bh = 0;
5151
5152         /* unrequested/ignored: Frame List Rollover */
5153         dbg_status(fotg210, "irq", status);
5154
5155         /* INT, ERR, and IAA interrupt rates can be throttled */
5156
5157         /* normal [4.15.1.2] or error [4.15.1.1] completion */
5158         if (likely((status & (STS_INT|STS_ERR)) != 0)) {
5159                 if (likely((status & STS_ERR) == 0))
5160                         INCR(fotg210->stats.normal);
5161                 else
5162                         INCR(fotg210->stats.error);
5163                 bh = 1;
5164         }
5165
5166         /* complete the unlinking of some qh [4.15.2.3] */
5167         if (status & STS_IAA) {
5168
5169                 /* Turn off the IAA watchdog */
5170                 fotg210->enabled_hrtimer_events &=
5171                         ~BIT(FOTG210_HRTIMER_IAA_WATCHDOG);
5172
5173                 /*
5174                  * Mild optimization: Allow another IAAD to reset the
5175                  * hrtimer, if one occurs before the next expiration.
5176                  * In theory we could always cancel the hrtimer, but
5177                  * tests show that about half the time it will be reset
5178                  * for some other event anyway.
5179                  */
5180                 if (fotg210->next_hrtimer_event == FOTG210_HRTIMER_IAA_WATCHDOG)
5181                         ++fotg210->next_hrtimer_event;
5182
5183                 /* guard against (alleged) silicon errata */
5184                 if (cmd & CMD_IAAD)
5185                         fotg210_dbg(fotg210, "IAA with IAAD still set?\n");
5186                 if (fotg210->async_iaa) {
5187                         INCR(fotg210->stats.iaa);
5188                         end_unlink_async(fotg210);
5189                 } else
5190                         fotg210_dbg(fotg210, "IAA with nothing unlinked?\n");
5191         }
5192
5193         /* remote wakeup [4.3.1] */
5194         if (status & STS_PCD) {
5195                 int pstatus;
5196                 u32 __iomem *status_reg = &fotg210->regs->port_status;
5197
5198                 /* kick root hub later */
5199                 pcd_status = status;
5200
5201                 /* resume root hub? */
5202                 if (fotg210->rh_state == FOTG210_RH_SUSPENDED)
5203                         usb_hcd_resume_root_hub(hcd);
5204
5205                 pstatus = fotg210_readl(fotg210, status_reg);
5206
5207                 if (test_bit(0, &fotg210->suspended_ports) &&
5208                                 ((pstatus & PORT_RESUME) ||
5209                                 !(pstatus & PORT_SUSPEND)) &&
5210                                 (pstatus & PORT_PE) &&
5211                                 fotg210->reset_done[0] == 0) {
5212
5213                         /* start 20 msec resume signaling from this port,
5214                          * and make hub_wq collect PORT_STAT_C_SUSPEND to
5215                          * stop that signaling.  Use 5 ms extra for safety,
5216                          * like usb_port_resume() does.
5217                          */
5218                         fotg210->reset_done[0] = jiffies + msecs_to_jiffies(25);
5219                         set_bit(0, &fotg210->resuming_ports);
5220                         fotg210_dbg(fotg210, "port 1 remote wakeup\n");
5221                         mod_timer(&hcd->rh_timer, fotg210->reset_done[0]);
5222                 }
5223         }
5224
5225         /* PCI errors [4.15.2.4] */
5226         if (unlikely((status & STS_FATAL) != 0)) {
5227                 fotg210_err(fotg210, "fatal error\n");
5228                 dbg_cmd(fotg210, "fatal", cmd);
5229                 dbg_status(fotg210, "fatal", status);
5230 dead:
5231                 usb_hc_died(hcd);
5232
5233                 /* Don't let the controller do anything more */
5234                 fotg210->shutdown = true;
5235                 fotg210->rh_state = FOTG210_RH_STOPPING;
5236                 fotg210->command &= ~(CMD_RUN | CMD_ASE | CMD_PSE);
5237                 fotg210_writel(fotg210, fotg210->command,
5238                                 &fotg210->regs->command);
5239                 fotg210_writel(fotg210, 0, &fotg210->regs->intr_enable);
5240                 fotg210_handle_controller_death(fotg210);
5241
5242                 /* Handle completions when the controller stops */
5243                 bh = 0;
5244         }
5245
5246         if (bh)
5247                 fotg210_work(fotg210);
5248         spin_unlock(&fotg210->lock);
5249         if (pcd_status)
5250                 usb_hcd_poll_rh_status(hcd);
5251         return IRQ_HANDLED;
5252 }
5253
5254 /* non-error returns are a promise to giveback() the urb later
5255  * we drop ownership so next owner (or urb unlink) can get it
5256  *
5257  * urb + dev is in hcd.self.controller.urb_list
5258  * we're queueing TDs onto software and hardware lists
5259  *
5260  * hcd-specific init for hcpriv hasn't been done yet
5261  *
5262  * NOTE:  control, bulk, and interrupt share the same code to append TDs
5263  * to a (possibly active) QH, and the same QH scanning code.
5264  */
5265 static int fotg210_urb_enqueue(struct usb_hcd *hcd, struct urb *urb,
5266                 gfp_t mem_flags)
5267 {
5268         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5269         struct list_head qtd_list;
5270
5271         INIT_LIST_HEAD(&qtd_list);
5272
5273         switch (usb_pipetype(urb->pipe)) {
5274         case PIPE_CONTROL:
5275                 /* qh_completions() code doesn't handle all the fault cases
5276                  * in multi-TD control transfers.  Even 1KB is rare anyway.
5277                  */
5278                 if (urb->transfer_buffer_length > (16 * 1024))
5279                         return -EMSGSIZE;
5280                 fallthrough;
5281         /* case PIPE_BULK: */
5282         default:
5283                 if (!qh_urb_transaction(fotg210, urb, &qtd_list, mem_flags))
5284                         return -ENOMEM;
5285                 return submit_async(fotg210, urb, &qtd_list, mem_flags);
5286
5287         case PIPE_INTERRUPT:
5288                 if (!qh_urb_transaction(fotg210, urb, &qtd_list, mem_flags))
5289                         return -ENOMEM;
5290                 return intr_submit(fotg210, urb, &qtd_list, mem_flags);
5291
5292         case PIPE_ISOCHRONOUS:
5293                 return itd_submit(fotg210, urb, mem_flags);
5294         }
5295 }
5296
5297 /* remove from hardware lists
5298  * completions normally happen asynchronously
5299  */
5300
5301 static int fotg210_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
5302 {
5303         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5304         struct fotg210_qh *qh;
5305         unsigned long flags;
5306         int rc;
5307
5308         spin_lock_irqsave(&fotg210->lock, flags);
5309         rc = usb_hcd_check_unlink_urb(hcd, urb, status);
5310         if (rc)
5311                 goto done;
5312
5313         switch (usb_pipetype(urb->pipe)) {
5314         /* case PIPE_CONTROL: */
5315         /* case PIPE_BULK:*/
5316         default:
5317                 qh = (struct fotg210_qh *) urb->hcpriv;
5318                 if (!qh)
5319                         break;
5320                 switch (qh->qh_state) {
5321                 case QH_STATE_LINKED:
5322                 case QH_STATE_COMPLETING:
5323                         start_unlink_async(fotg210, qh);
5324                         break;
5325                 case QH_STATE_UNLINK:
5326                 case QH_STATE_UNLINK_WAIT:
5327                         /* already started */
5328                         break;
5329                 case QH_STATE_IDLE:
5330                         /* QH might be waiting for a Clear-TT-Buffer */
5331                         qh_completions(fotg210, qh);
5332                         break;
5333                 }
5334                 break;
5335
5336         case PIPE_INTERRUPT:
5337                 qh = (struct fotg210_qh *) urb->hcpriv;
5338                 if (!qh)
5339                         break;
5340                 switch (qh->qh_state) {
5341                 case QH_STATE_LINKED:
5342                 case QH_STATE_COMPLETING:
5343                         start_unlink_intr(fotg210, qh);
5344                         break;
5345                 case QH_STATE_IDLE:
5346                         qh_completions(fotg210, qh);
5347                         break;
5348                 default:
5349                         fotg210_dbg(fotg210, "bogus qh %p state %d\n",
5350                                         qh, qh->qh_state);
5351                         goto done;
5352                 }
5353                 break;
5354
5355         case PIPE_ISOCHRONOUS:
5356                 /* itd... */
5357
5358                 /* wait till next completion, do it then. */
5359                 /* completion irqs can wait up to 1024 msec, */
5360                 break;
5361         }
5362 done:
5363         spin_unlock_irqrestore(&fotg210->lock, flags);
5364         return rc;
5365 }
5366
5367 /* bulk qh holds the data toggle */
5368
5369 static void fotg210_endpoint_disable(struct usb_hcd *hcd,
5370                 struct usb_host_endpoint *ep)
5371 {
5372         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5373         unsigned long flags;
5374         struct fotg210_qh *qh, *tmp;
5375
5376         /* ASSERT:  any requests/urbs are being unlinked */
5377         /* ASSERT:  nobody can be submitting urbs for this any more */
5378
5379 rescan:
5380         spin_lock_irqsave(&fotg210->lock, flags);
5381         qh = ep->hcpriv;
5382         if (!qh)
5383                 goto done;
5384
5385         /* endpoints can be iso streams.  for now, we don't
5386          * accelerate iso completions ... so spin a while.
5387          */
5388         if (qh->hw == NULL) {
5389                 struct fotg210_iso_stream *stream = ep->hcpriv;
5390
5391                 if (!list_empty(&stream->td_list))
5392                         goto idle_timeout;
5393
5394                 /* BUG_ON(!list_empty(&stream->free_list)); */
5395                 kfree(stream);
5396                 goto done;
5397         }
5398
5399         if (fotg210->rh_state < FOTG210_RH_RUNNING)
5400                 qh->qh_state = QH_STATE_IDLE;
5401         switch (qh->qh_state) {
5402         case QH_STATE_LINKED:
5403         case QH_STATE_COMPLETING:
5404                 for (tmp = fotg210->async->qh_next.qh;
5405                                 tmp && tmp != qh;
5406                                 tmp = tmp->qh_next.qh)
5407                         continue;
5408                 /* periodic qh self-unlinks on empty, and a COMPLETING qh
5409                  * may already be unlinked.
5410                  */
5411                 if (tmp)
5412                         start_unlink_async(fotg210, qh);
5413                 fallthrough;
5414         case QH_STATE_UNLINK:           /* wait for hw to finish? */
5415         case QH_STATE_UNLINK_WAIT:
5416 idle_timeout:
5417                 spin_unlock_irqrestore(&fotg210->lock, flags);
5418                 schedule_timeout_uninterruptible(1);
5419                 goto rescan;
5420         case QH_STATE_IDLE:             /* fully unlinked */
5421                 if (qh->clearing_tt)
5422                         goto idle_timeout;
5423                 if (list_empty(&qh->qtd_list)) {
5424                         qh_destroy(fotg210, qh);
5425                         break;
5426                 }
5427                 fallthrough;
5428         default:
5429                 /* caller was supposed to have unlinked any requests;
5430                  * that's not our job.  just leak this memory.
5431                  */
5432                 fotg210_err(fotg210, "qh %p (#%02x) state %d%s\n",
5433                                 qh, ep->desc.bEndpointAddress, qh->qh_state,
5434                                 list_empty(&qh->qtd_list) ? "" : "(has tds)");
5435                 break;
5436         }
5437 done:
5438         ep->hcpriv = NULL;
5439         spin_unlock_irqrestore(&fotg210->lock, flags);
5440 }
5441
5442 static void fotg210_endpoint_reset(struct usb_hcd *hcd,
5443                 struct usb_host_endpoint *ep)
5444 {
5445         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5446         struct fotg210_qh *qh;
5447         int eptype = usb_endpoint_type(&ep->desc);
5448         int epnum = usb_endpoint_num(&ep->desc);
5449         int is_out = usb_endpoint_dir_out(&ep->desc);
5450         unsigned long flags;
5451
5452         if (eptype != USB_ENDPOINT_XFER_BULK && eptype != USB_ENDPOINT_XFER_INT)
5453                 return;
5454
5455         spin_lock_irqsave(&fotg210->lock, flags);
5456         qh = ep->hcpriv;
5457
5458         /* For Bulk and Interrupt endpoints we maintain the toggle state
5459          * in the hardware; the toggle bits in udev aren't used at all.
5460          * When an endpoint is reset by usb_clear_halt() we must reset
5461          * the toggle bit in the QH.
5462          */
5463         if (qh) {
5464                 usb_settoggle(qh->dev, epnum, is_out, 0);
5465                 if (!list_empty(&qh->qtd_list)) {
5466                         WARN_ONCE(1, "clear_halt for a busy endpoint\n");
5467                 } else if (qh->qh_state == QH_STATE_LINKED ||
5468                                 qh->qh_state == QH_STATE_COMPLETING) {
5469
5470                         /* The toggle value in the QH can't be updated
5471                          * while the QH is active.  Unlink it now;
5472                          * re-linking will call qh_refresh().
5473                          */
5474                         if (eptype == USB_ENDPOINT_XFER_BULK)
5475                                 start_unlink_async(fotg210, qh);
5476                         else
5477                                 start_unlink_intr(fotg210, qh);
5478                 }
5479         }
5480         spin_unlock_irqrestore(&fotg210->lock, flags);
5481 }
5482
5483 static int fotg210_get_frame(struct usb_hcd *hcd)
5484 {
5485         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5486
5487         return (fotg210_read_frame_index(fotg210) >> 3) %
5488                 fotg210->periodic_size;
5489 }
5490
5491 /* The EHCI in ChipIdea HDRC cannot be a separate module or device,
5492  * because its registers (and irq) are shared between host/gadget/otg
5493  * functions  and in order to facilitate role switching we cannot
5494  * give the fotg210 driver exclusive access to those.
5495  */
5496 MODULE_DESCRIPTION(DRIVER_DESC);
5497 MODULE_AUTHOR(DRIVER_AUTHOR);
5498 MODULE_LICENSE("GPL");
5499
5500 static const struct hc_driver fotg210_fotg210_hc_driver = {
5501         .description            = hcd_name,
5502         .product_desc           = "Faraday USB2.0 Host Controller",
5503         .hcd_priv_size          = sizeof(struct fotg210_hcd),
5504
5505         /*
5506          * generic hardware linkage
5507          */
5508         .irq                    = fotg210_irq,
5509         .flags                  = HCD_MEMORY | HCD_DMA | HCD_USB2,
5510
5511         /*
5512          * basic lifecycle operations
5513          */
5514         .reset                  = hcd_fotg210_init,
5515         .start                  = fotg210_run,
5516         .stop                   = fotg210_stop,
5517         .shutdown               = fotg210_shutdown,
5518
5519         /*
5520          * managing i/o requests and associated device resources
5521          */
5522         .urb_enqueue            = fotg210_urb_enqueue,
5523         .urb_dequeue            = fotg210_urb_dequeue,
5524         .endpoint_disable       = fotg210_endpoint_disable,
5525         .endpoint_reset         = fotg210_endpoint_reset,
5526
5527         /*
5528          * scheduling support
5529          */
5530         .get_frame_number       = fotg210_get_frame,
5531
5532         /*
5533          * root hub support
5534          */
5535         .hub_status_data        = fotg210_hub_status_data,
5536         .hub_control            = fotg210_hub_control,
5537         .bus_suspend            = fotg210_bus_suspend,
5538         .bus_resume             = fotg210_bus_resume,
5539
5540         .relinquish_port        = fotg210_relinquish_port,
5541         .port_handed_over       = fotg210_port_handed_over,
5542
5543         .clear_tt_buffer_complete = fotg210_clear_tt_buffer_complete,
5544 };
5545
5546 static void fotg210_init(struct fotg210_hcd *fotg210)
5547 {
5548         u32 value;
5549
5550         iowrite32(GMIR_MDEV_INT | GMIR_MOTG_INT | GMIR_INT_POLARITY,
5551                         &fotg210->regs->gmir);
5552
5553         value = ioread32(&fotg210->regs->otgcsr);
5554         value &= ~OTGCSR_A_BUS_DROP;
5555         value |= OTGCSR_A_BUS_REQ;
5556         iowrite32(value, &fotg210->regs->otgcsr);
5557 }
5558
5559 /*
5560  * fotg210_hcd_probe - initialize faraday FOTG210 HCDs
5561  *
5562  * Allocates basic resources for this USB host controller, and
5563  * then invokes the start() method for the HCD associated with it
5564  * through the hotplug entry's driver_data.
5565  */
5566 static int fotg210_hcd_probe(struct platform_device *pdev)
5567 {
5568         struct device *dev = &pdev->dev;
5569         struct usb_hcd *hcd;
5570         struct resource *res;
5571         int irq;
5572         int retval;
5573         struct fotg210_hcd *fotg210;
5574
5575         if (usb_disabled())
5576                 return -ENODEV;
5577
5578         pdev->dev.power.power_state = PMSG_ON;
5579
5580         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
5581         if (!res) {
5582                 dev_err(dev, "Found HC with no IRQ. Check %s setup!\n",
5583                                 dev_name(dev));
5584                 return -ENODEV;
5585         }
5586
5587         irq = res->start;
5588
5589         hcd = usb_create_hcd(&fotg210_fotg210_hc_driver, dev,
5590                         dev_name(dev));
5591         if (!hcd) {
5592                 dev_err(dev, "failed to create hcd\n");
5593                 retval = -ENOMEM;
5594                 goto fail_create_hcd;
5595         }
5596
5597         hcd->has_tt = 1;
5598
5599         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
5600         hcd->regs = devm_ioremap_resource(&pdev->dev, res);
5601         if (IS_ERR(hcd->regs)) {
5602                 retval = PTR_ERR(hcd->regs);
5603                 goto failed_put_hcd;
5604         }
5605
5606         hcd->rsrc_start = res->start;
5607         hcd->rsrc_len = resource_size(res);
5608
5609         fotg210 = hcd_to_fotg210(hcd);
5610
5611         fotg210->caps = hcd->regs;
5612
5613         /* It's OK not to supply this clock */
5614         fotg210->pclk = clk_get(dev, "PCLK");
5615         if (!IS_ERR(fotg210->pclk)) {
5616                 retval = clk_prepare_enable(fotg210->pclk);
5617                 if (retval) {
5618                         dev_err(dev, "failed to enable PCLK\n");
5619                         goto failed_put_hcd;
5620                 }
5621         } else if (PTR_ERR(fotg210->pclk) == -EPROBE_DEFER) {
5622                 /*
5623                  * Percolate deferrals, for anything else,
5624                  * just live without the clocking.
5625                  */
5626                 retval = PTR_ERR(fotg210->pclk);
5627                 goto failed_dis_clk;
5628         }
5629
5630         retval = fotg210_setup(hcd);
5631         if (retval)
5632                 goto failed_dis_clk;
5633
5634         fotg210_init(fotg210);
5635
5636         retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
5637         if (retval) {
5638                 dev_err(dev, "failed to add hcd with err %d\n", retval);
5639                 goto failed_dis_clk;
5640         }
5641         device_wakeup_enable(hcd->self.controller);
5642         platform_set_drvdata(pdev, hcd);
5643
5644         return retval;
5645
5646 failed_dis_clk:
5647         if (!IS_ERR(fotg210->pclk)) {
5648                 clk_disable_unprepare(fotg210->pclk);
5649                 clk_put(fotg210->pclk);
5650         }
5651 failed_put_hcd:
5652         usb_put_hcd(hcd);
5653 fail_create_hcd:
5654         dev_err(dev, "init %s fail, %d\n", dev_name(dev), retval);
5655         return retval;
5656 }
5657
5658 /*
5659  * fotg210_hcd_remove - shutdown processing for EHCI HCDs
5660  * @dev: USB Host Controller being removed
5661  *
5662  */
5663 static int fotg210_hcd_remove(struct platform_device *pdev)
5664 {
5665         struct usb_hcd *hcd = platform_get_drvdata(pdev);
5666         struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
5667
5668         if (!IS_ERR(fotg210->pclk)) {
5669                 clk_disable_unprepare(fotg210->pclk);
5670                 clk_put(fotg210->pclk);
5671         }
5672
5673         usb_remove_hcd(hcd);
5674         usb_put_hcd(hcd);
5675
5676         return 0;
5677 }
5678
5679 #ifdef CONFIG_OF
5680 static const struct of_device_id fotg210_of_match[] = {
5681         { .compatible = "faraday,fotg210" },
5682         {},
5683 };
5684 MODULE_DEVICE_TABLE(of, fotg210_of_match);
5685 #endif
5686
5687 static struct platform_driver fotg210_hcd_driver = {
5688         .driver = {
5689                 .name   = "fotg210-hcd",
5690                 .of_match_table = of_match_ptr(fotg210_of_match),
5691         },
5692         .probe  = fotg210_hcd_probe,
5693         .remove = fotg210_hcd_remove,
5694 };
5695
5696 static int __init fotg210_hcd_init(void)
5697 {
5698         int retval = 0;
5699
5700         if (usb_disabled())
5701                 return -ENODEV;
5702
5703         pr_info("%s: " DRIVER_DESC "\n", hcd_name);
5704         set_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
5705         if (test_bit(USB_UHCI_LOADED, &usb_hcds_loaded) ||
5706                         test_bit(USB_OHCI_LOADED, &usb_hcds_loaded))
5707                 pr_warn("Warning! fotg210_hcd should always be loaded before uhci_hcd and ohci_hcd, not after\n");
5708
5709         pr_debug("%s: block sizes: qh %zd qtd %zd itd %zd\n",
5710                         hcd_name, sizeof(struct fotg210_qh),
5711                         sizeof(struct fotg210_qtd),
5712                         sizeof(struct fotg210_itd));
5713
5714         fotg210_debug_root = debugfs_create_dir("fotg210", usb_debug_root);
5715
5716         retval = platform_driver_register(&fotg210_hcd_driver);
5717         if (retval < 0)
5718                 goto clean;
5719         return retval;
5720
5721 clean:
5722         debugfs_remove(fotg210_debug_root);
5723         fotg210_debug_root = NULL;
5724
5725         clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
5726         return retval;
5727 }
5728 module_init(fotg210_hcd_init);
5729
5730 static void __exit fotg210_hcd_cleanup(void)
5731 {
5732         platform_driver_unregister(&fotg210_hcd_driver);
5733         debugfs_remove(fotg210_debug_root);
5734         clear_bit(USB_EHCI_LOADED, &usb_hcds_loaded);
5735 }
5736 module_exit(fotg210_hcd_cleanup);