drivers/soundwire/bus.c

   1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
   2 // Copyright(c) 2015-17 Intel Corporation.
   3
   4 #include <linux/acpi.h>
   5 #include <linux/delay.h>
   6 #include <linux/mod_devicetable.h>
   7 #include <linux/pm_runtime.h>
   8 #include <linux/soundwire/sdw_registers.h>
   9 #include <linux/soundwire/sdw.h>
  10 #include "bus.h"
  11 #include "sysfs_local.h"
  12
  13 static DEFINE_IDA(sdw_ida);
  14
  15 static int sdw_get_id(struct sdw_bus *bus)
  16 {
  17         int rc = ida_alloc(&sdw_ida, GFP_KERNEL);
  18
  19         if (rc < 0)
  20                 return rc;
  21
  22         bus->id = rc;
  23         return 0;
  24 }
  25
  26 /**
  27  * sdw_bus_master_add() - add a bus Master instance
  28  * @bus: bus instance
  29  * @parent: parent device
  30  * @fwnode: firmware node handle
  31  *
  32  * Initializes the bus instance, read properties and create child
  33  * devices.
  34  */
  35 int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent,
  36                        struct fwnode_handle *fwnode)
  37 {
  38         struct sdw_master_prop *prop = NULL;
  39         int ret;
  40
  41         if (!parent) {
  42                 pr_err("SoundWire parent device is not set\n");
  43                 return -ENODEV;
  44         }
  45
  46         ret = sdw_get_id(bus);
  47         if (ret < 0) {
  48                 dev_err(parent, "Failed to get bus id\n");
  49                 return ret;
  50         }
  51
  52         ret = sdw_master_device_add(bus, parent, fwnode);
  53         if (ret < 0) {
  54                 dev_err(parent, "Failed to add master device at link %d\n",
  55                         bus->link_id);
  56                 return ret;
  57         }
  58
  59         if (!bus->ops) {
  60                 dev_err(bus->dev, "SoundWire Bus ops are not set\n");
  61                 return -EINVAL;
  62         }
  63
  64         if (!bus->compute_params) {
  65                 dev_err(bus->dev,
  66                         "Bandwidth allocation not configured, compute_params no set\n");
  67                 return -EINVAL;
  68         }
  69
  70         mutex_init(&bus->msg_lock);
  71         mutex_init(&bus->bus_lock);
  72         INIT_LIST_HEAD(&bus->slaves);
  73         INIT_LIST_HEAD(&bus->m_rt_list);
  74
  75         /*
  76          * Initialize multi_link flag
  77          * TODO: populate this flag by reading property from FW node
  78          */
  79         bus->multi_link = false;
  80         if (bus->ops->read_prop) {
  81                 ret = bus->ops->read_prop(bus);
  82                 if (ret < 0) {
  83                         dev_err(bus->dev,
  84                                 "Bus read properties failed:%d\n", ret);
  85                         return ret;
  86                 }
  87         }
  88
  89         sdw_bus_debugfs_init(bus);
  90
  91         /*
  92          * Device numbers in SoundWire are 0 through 15. Enumeration device
  93          * number (0), Broadcast device number (15), Group numbers (12 and
  94          * 13) and Master device number (14) are not used for assignment so
  95          * mask these and other higher bits.
  96          */
  97
  98         /* Set higher order bits */
  99         *bus->assigned = ~GENMASK(SDW_BROADCAST_DEV_NUM, SDW_ENUM_DEV_NUM);
 100
 101         /* Set enumuration device number and broadcast device number */
 102         set_bit(SDW_ENUM_DEV_NUM, bus->assigned);
 103         set_bit(SDW_BROADCAST_DEV_NUM, bus->assigned);
 104
 105         /* Set group device numbers and master device number */
 106         set_bit(SDW_GROUP12_DEV_NUM, bus->assigned);
 107         set_bit(SDW_GROUP13_DEV_NUM, bus->assigned);
 108         set_bit(SDW_MASTER_DEV_NUM, bus->assigned);
 109
 110         /*
 111          * SDW is an enumerable bus, but devices can be powered off. So,
 112          * they won't be able to report as present.
 113          *
 114          * Create Slave devices based on Slaves described in
 115          * the respective firmware (ACPI/DT)
 116          */
 117         if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev))
 118                 ret = sdw_acpi_find_slaves(bus);
 119         else if (IS_ENABLED(CONFIG_OF) && bus->dev->of_node)
 120                 ret = sdw_of_find_slaves(bus);
 121         else
 122                 ret = -ENOTSUPP; /* No ACPI/DT so error out */
 123
 124         if (ret < 0) {
 125                 dev_err(bus->dev, "Finding slaves failed:%d\n", ret);
 126                 return ret;
 127         }
 128
 129         /*
 130          * Initialize clock values based on Master properties. The max
 131          * frequency is read from max_clk_freq property. Current assumption
 132          * is that the bus will start at highest clock frequency when
 133          * powered on.
 134          *
 135          * Default active bank will be 0 as out of reset the Slaves have
 136          * to start with bank 0 (Table 40 of Spec)
 137          */
 138         prop = &bus->prop;
 139         bus->params.max_dr_freq = prop->max_clk_freq * SDW_DOUBLE_RATE_FACTOR;
 140         bus->params.curr_dr_freq = bus->params.max_dr_freq;
 141         bus->params.curr_bank = SDW_BANK0;
 142         bus->params.next_bank = SDW_BANK1;
 143
 144         return 0;
 145 }
 146 EXPORT_SYMBOL(sdw_bus_master_add);
 147
 148 static int sdw_delete_slave(struct device *dev, void *data)
 149 {
 150         struct sdw_slave *slave = dev_to_sdw_dev(dev);
 151         struct sdw_bus *bus = slave->bus;
 152
 153         pm_runtime_disable(dev);
 154
 155         sdw_slave_debugfs_exit(slave);
 156
 157         mutex_lock(&bus->bus_lock);
 158
 159         if (slave->dev_num) /* clear dev_num if assigned */
 160                 clear_bit(slave->dev_num, bus->assigned);
 161
 162         list_del_init(&slave->node);
 163         mutex_unlock(&bus->bus_lock);
 164
 165         device_unregister(dev);
 166         return 0;
 167 }
 168
 169 /**
 170  * sdw_bus_master_delete() - delete the bus master instance
 171  * @bus: bus to be deleted
 172  *
 173  * Remove the instance, delete the child devices.
 174  */
 175 void sdw_bus_master_delete(struct sdw_bus *bus)
 176 {
 177         device_for_each_child(bus->dev, NULL, sdw_delete_slave);
 178         sdw_master_device_del(bus);
 179
 180         sdw_bus_debugfs_exit(bus);
 181         ida_free(&sdw_ida, bus->id);
 182 }
 183 EXPORT_SYMBOL(sdw_bus_master_delete);
 184
 185 /*
 186  * SDW IO Calls
 187  */
 188
 189 static inline int find_response_code(enum sdw_command_response resp)
 190 {
 191         switch (resp) {
 192         case SDW_CMD_OK:
 193                 return 0;
 194
 195         case SDW_CMD_IGNORED:
 196                 return -ENODATA;
 197
 198         case SDW_CMD_TIMEOUT:
 199                 return -ETIMEDOUT;
 200
 201         default:
 202                 return -EIO;
 203         }
 204 }
 205
 206 static inline int do_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 207 {
 208         int retry = bus->prop.err_threshold;
 209         enum sdw_command_response resp;
 210         int ret = 0, i;
 211
 212         for (i = 0; i <= retry; i++) {
 213                 resp = bus->ops->xfer_msg(bus, msg);
 214                 ret = find_response_code(resp);
 215
 216                 /* if cmd is ok or ignored return */
 217                 if (ret == 0 || ret == -ENODATA)
 218                         return ret;
 219         }
 220
 221         return ret;
 222 }
 223
 224 static inline int do_transfer_defer(struct sdw_bus *bus,
 225                                     struct sdw_msg *msg,
 226                                     struct sdw_defer *defer)
 227 {
 228         int retry = bus->prop.err_threshold;
 229         enum sdw_command_response resp;
 230         int ret = 0, i;
 231
 232         defer->msg = msg;
 233         defer->length = msg->len;
 234         init_completion(&defer->complete);
 235
 236         for (i = 0; i <= retry; i++) {
 237                 resp = bus->ops->xfer_msg_defer(bus, msg, defer);
 238                 ret = find_response_code(resp);
 239                 /* if cmd is ok or ignored return */
 240                 if (ret == 0 || ret == -ENODATA)
 241                         return ret;
 242         }
 243
 244         return ret;
 245 }
 246
 247 static int sdw_reset_page(struct sdw_bus *bus, u16 dev_num)
 248 {
 249         int retry = bus->prop.err_threshold;
 250         enum sdw_command_response resp;
 251         int ret = 0, i;
 252
 253         for (i = 0; i <= retry; i++) {
 254                 resp = bus->ops->reset_page_addr(bus, dev_num);
 255                 ret = find_response_code(resp);
 256                 /* if cmd is ok or ignored return */
 257                 if (ret == 0 || ret == -ENODATA)
 258                         return ret;
 259         }
 260
 261         return ret;
 262 }
 263
 264 static int sdw_transfer_unlocked(struct sdw_bus *bus, struct sdw_msg *msg)
 265 {
 266         int ret;
 267
 268         ret = do_transfer(bus, msg);
 269         if (ret != 0 && ret != -ENODATA)
 270                 dev_err(bus->dev, "trf on Slave %d failed:%d %s addr %x count %d\n",
 271                         msg->dev_num, ret,
 272                         (msg->flags & SDW_MSG_FLAG_WRITE) ? "write" : "read",
 273                         msg->addr, msg->len);
 274
 275         if (msg->page)
 276                 sdw_reset_page(bus, msg->dev_num);
 277
 278         return ret;
 279 }
 280
 281 /**
 282  * sdw_transfer() - Synchronous transfer message to a SDW Slave device
 283  * @bus: SDW bus
 284  * @msg: SDW message to be xfered
 285  */
 286 int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 287 {
 288         int ret;
 289
 290         mutex_lock(&bus->msg_lock);
 291
 292         ret = sdw_transfer_unlocked(bus, msg);
 293
 294         mutex_unlock(&bus->msg_lock);
 295
 296         return ret;
 297 }
 298
 299 /**
 300  * sdw_transfer_defer() - Asynchronously transfer message to a SDW Slave device
 301  * @bus: SDW bus
 302  * @msg: SDW message to be xfered
 303  * @defer: Defer block for signal completion
 304  *
 305  * Caller needs to hold the msg_lock lock while calling this
 306  */
 307 int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg,
 308                        struct sdw_defer *defer)
 309 {
 310         int ret;
 311
 312         if (!bus->ops->xfer_msg_defer)
 313                 return -ENOTSUPP;
 314
 315         ret = do_transfer_defer(bus, msg, defer);
 316         if (ret != 0 && ret != -ENODATA)
 317                 dev_err(bus->dev, "Defer trf on Slave %d failed:%d\n",
 318                         msg->dev_num, ret);
 319
 320         if (msg->page)
 321                 sdw_reset_page(bus, msg->dev_num);
 322
 323         return ret;
 324 }
 325
 326 int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
 327                  u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf)
 328 {
 329         memset(msg, 0, sizeof(*msg));
 330         msg->addr = addr; /* addr is 16 bit and truncated here */
 331         msg->len = count;
 332         msg->dev_num = dev_num;
 333         msg->flags = flags;
 334         msg->buf = buf;
 335
 336         if (addr < SDW_REG_NO_PAGE) /* no paging area */
 337                 return 0;
 338
 339         if (addr >= SDW_REG_MAX) { /* illegal addr */
 340                 pr_err("SDW: Invalid address %x passed\n", addr);
 341                 return -EINVAL;
 342         }
 343
 344         if (addr < SDW_REG_OPTIONAL_PAGE) { /* 32k but no page */
 345                 if (slave && !slave->prop.paging_support)
 346                         return 0;
 347                 /* no need for else as that will fall-through to paging */
 348         }
 349
 350         /* paging mandatory */
 351         if (dev_num == SDW_ENUM_DEV_NUM || dev_num == SDW_BROADCAST_DEV_NUM) {
 352                 pr_err("SDW: Invalid device for paging :%d\n", dev_num);
 353                 return -EINVAL;
 354         }
 355
 356         if (!slave) {
 357                 pr_err("SDW: No slave for paging addr\n");
 358                 return -EINVAL;
 359         }
 360
 361         if (!slave->prop.paging_support) {
 362                 dev_err(&slave->dev,
 363                         "address %x needs paging but no support\n", addr);
 364                 return -EINVAL;
 365         }
 366
 367         msg->addr_page1 = FIELD_GET(SDW_SCP_ADDRPAGE1_MASK, addr);
 368         msg->addr_page2 = FIELD_GET(SDW_SCP_ADDRPAGE2_MASK, addr);
 369         msg->addr |= BIT(15);
 370         msg->page = true;
 371
 372         return 0;
 373 }
 374
 375 /*
 376  * Read/Write IO functions.
 377  * no_pm versions can only be called by the bus, e.g. while enumerating or
 378  * handling suspend-resume sequences.
 379  * all clients need to use the pm versions
 380  */
 381
 382 static int
 383 sdw_nread_no_pm(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 384 {
 385         struct sdw_msg msg;
 386         int ret;
 387
 388         ret = sdw_fill_msg(&msg, slave, addr, count,
 389                            slave->dev_num, SDW_MSG_FLAG_READ, val);
 390         if (ret < 0)
 391                 return ret;
 392
 393         return sdw_transfer(slave->bus, &msg);
 394 }
 395
 396 static int
 397 sdw_nwrite_no_pm(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 398 {
 399         struct sdw_msg msg;
 400         int ret;
 401
 402         ret = sdw_fill_msg(&msg, slave, addr, count,
 403                            slave->dev_num, SDW_MSG_FLAG_WRITE, (u8 *)val);
 404         if (ret < 0)
 405                 return ret;
 406
 407         return sdw_transfer(slave->bus, &msg);
 408 }
 409
 410 int sdw_write_no_pm(struct sdw_slave *slave, u32 addr, u8 value)
 411 {
 412         return sdw_nwrite_no_pm(slave, addr, 1, &value);
 413 }
 414 EXPORT_SYMBOL(sdw_write_no_pm);
 415
 416 static int
 417 sdw_bread_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr)
 418 {
 419         struct sdw_msg msg;
 420         u8 buf;
 421         int ret;
 422
 423         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 424                            SDW_MSG_FLAG_READ, &buf);
 425         if (ret < 0)
 426                 return ret;
 427
 428         ret = sdw_transfer(bus, &msg);
 429         if (ret < 0)
 430                 return ret;
 431
 432         return buf;
 433 }
 434
 435 static int
 436 sdw_bwrite_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 437 {
 438         struct sdw_msg msg;
 439         int ret;
 440
 441         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 442                            SDW_MSG_FLAG_WRITE, &value);
 443         if (ret < 0)
 444                 return ret;
 445
 446         return sdw_transfer(bus, &msg);
 447 }
 448
 449 int sdw_bread_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr)
 450 {
 451         struct sdw_msg msg;
 452         u8 buf;
 453         int ret;
 454
 455         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 456                            SDW_MSG_FLAG_READ, &buf);
 457         if (ret < 0)
 458                 return ret;
 459
 460         ret = sdw_transfer_unlocked(bus, &msg);
 461         if (ret < 0)
 462                 return ret;
 463
 464         return buf;
 465 }
 466 EXPORT_SYMBOL(sdw_bread_no_pm_unlocked);
 467
 468 int sdw_bwrite_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 469 {
 470         struct sdw_msg msg;
 471         int ret;
 472
 473         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 474                            SDW_MSG_FLAG_WRITE, &value);
 475         if (ret < 0)
 476                 return ret;
 477
 478         return sdw_transfer_unlocked(bus, &msg);
 479 }
 480 EXPORT_SYMBOL(sdw_bwrite_no_pm_unlocked);
 481
 482 int sdw_read_no_pm(struct sdw_slave *slave, u32 addr)
 483 {
 484         u8 buf;
 485         int ret;
 486
 487         ret = sdw_nread_no_pm(slave, addr, 1, &buf);
 488         if (ret < 0)
 489                 return ret;
 490         else
 491                 return buf;
 492 }
 493 EXPORT_SYMBOL(sdw_read_no_pm);
 494
 495 static int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 496 {
 497         int tmp;
 498
 499         tmp = sdw_read_no_pm(slave, addr);
 500         if (tmp < 0)
 501                 return tmp;
 502
 503         tmp = (tmp & ~mask) | val;
 504         return sdw_write_no_pm(slave, addr, tmp);
 505 }
 506
 507 /**
 508  * sdw_nread() - Read "n" contiguous SDW Slave registers
 509  * @slave: SDW Slave
 510  * @addr: Register address
 511  * @count: length
 512  * @val: Buffer for values to be read
 513  */
 514 int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 515 {
 516         int ret;
 517
 518         ret = pm_runtime_get_sync(&slave->dev);
 519         if (ret < 0 && ret != -EACCES) {
 520                 pm_runtime_put_noidle(&slave->dev);
 521                 return ret;
 522         }
 523
 524         ret = sdw_nread_no_pm(slave, addr, count, val);
 525
 526         pm_runtime_mark_last_busy(&slave->dev);
 527         pm_runtime_put(&slave->dev);
 528
 529         return ret;
 530 }
 531 EXPORT_SYMBOL(sdw_nread);
 532
 533 /**
 534  * sdw_nwrite() - Write "n" contiguous SDW Slave registers
 535  * @slave: SDW Slave
 536  * @addr: Register address
 537  * @count: length
 538  * @val: Buffer for values to be written
 539  */
 540 int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 541 {
 542         int ret;
 543
 544         ret = pm_runtime_get_sync(&slave->dev);
 545         if (ret < 0 && ret != -EACCES) {
 546                 pm_runtime_put_noidle(&slave->dev);
 547                 return ret;
 548         }
 549
 550         ret = sdw_nwrite_no_pm(slave, addr, count, val);
 551
 552         pm_runtime_mark_last_busy(&slave->dev);
 553         pm_runtime_put(&slave->dev);
 554
 555         return ret;
 556 }
 557 EXPORT_SYMBOL(sdw_nwrite);
 558
 559 /**
 560  * sdw_read() - Read a SDW Slave register
 561  * @slave: SDW Slave
 562  * @addr: Register address
 563  */
 564 int sdw_read(struct sdw_slave *slave, u32 addr)
 565 {
 566         u8 buf;
 567         int ret;
 568
 569         ret = sdw_nread(slave, addr, 1, &buf);
 570         if (ret < 0)
 571                 return ret;
 572
 573         return buf;
 574 }
 575 EXPORT_SYMBOL(sdw_read);
 576
 577 /**
 578  * sdw_write() - Write a SDW Slave register
 579  * @slave: SDW Slave
 580  * @addr: Register address
 581  * @value: Register value
 582  */
 583 int sdw_write(struct sdw_slave *slave, u32 addr, u8 value)
 584 {
 585         return sdw_nwrite(slave, addr, 1, &value);
 586 }
 587 EXPORT_SYMBOL(sdw_write);
 588
 589 /*
 590  * SDW alert handling
 591  */
 592
 593 /* called with bus_lock held */
 594 static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i)
 595 {
 596         struct sdw_slave *slave;
 597
 598         list_for_each_entry(slave, &bus->slaves, node) {
 599                 if (slave->dev_num == i)
 600                         return slave;
 601         }
 602
 603         return NULL;
 604 }
 605
 606 int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id)
 607 {
 608         if (slave->id.mfg_id != id.mfg_id ||
 609             slave->id.part_id != id.part_id ||
 610             slave->id.class_id != id.class_id ||
 611             (slave->id.unique_id != SDW_IGNORED_UNIQUE_ID &&
 612              slave->id.unique_id != id.unique_id))
 613                 return -ENODEV;
 614
 615         return 0;
 616 }
 617 EXPORT_SYMBOL(sdw_compare_devid);
 618
 619 /* called with bus_lock held */
 620 static int sdw_get_device_num(struct sdw_slave *slave)
 621 {
 622         int bit;
 623
 624         bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES);
 625         if (bit == SDW_MAX_DEVICES) {
 626                 bit = -ENODEV;
 627                 goto err;
 628         }
 629
 630         /*
 631          * Do not update dev_num in Slave data structure here,
 632          * Update once program dev_num is successful
 633          */
 634         set_bit(bit, slave->bus->assigned);
 635
 636 err:
 637         return bit;
 638 }
 639
 640 static int sdw_assign_device_num(struct sdw_slave *slave)
 641 {
 642         struct sdw_bus *bus = slave->bus;
 643         int ret, dev_num;
 644         bool new_device = false;
 645
 646         /* check first if device number is assigned, if so reuse that */
 647         if (!slave->dev_num) {
 648                 if (!slave->dev_num_sticky) {
 649                         mutex_lock(&slave->bus->bus_lock);
 650                         dev_num = sdw_get_device_num(slave);
 651                         mutex_unlock(&slave->bus->bus_lock);
 652                         if (dev_num < 0) {
 653                                 dev_err(bus->dev, "Get dev_num failed: %d\n",
 654                                         dev_num);
 655                                 return dev_num;
 656                         }
 657                         slave->dev_num = dev_num;
 658                         slave->dev_num_sticky = dev_num;
 659                         new_device = true;
 660                 } else {
 661                         slave->dev_num = slave->dev_num_sticky;
 662                 }
 663         }
 664
 665         if (!new_device)
 666                 dev_dbg(bus->dev,
 667                         "Slave already registered, reusing dev_num:%d\n",
 668                         slave->dev_num);
 669
 670         /* Clear the slave->dev_num to transfer message on device 0 */
 671         dev_num = slave->dev_num;
 672         slave->dev_num = 0;
 673
 674         ret = sdw_write_no_pm(slave, SDW_SCP_DEVNUMBER, dev_num);
 675         if (ret < 0) {
 676                 dev_err(bus->dev, "Program device_num %d failed: %d\n",
 677                         dev_num, ret);
 678                 return ret;
 679         }
 680
 681         /* After xfer of msg, restore dev_num */
 682         slave->dev_num = slave->dev_num_sticky;
 683
 684         return 0;
 685 }
 686
 687 void sdw_extract_slave_id(struct sdw_bus *bus,
 688                           u64 addr, struct sdw_slave_id *id)
 689 {
 690         dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr);
 691
 692         id->sdw_version = SDW_VERSION(addr);
 693         id->unique_id = SDW_UNIQUE_ID(addr);
 694         id->mfg_id = SDW_MFG_ID(addr);
 695         id->part_id = SDW_PART_ID(addr);
 696         id->class_id = SDW_CLASS_ID(addr);
 697
 698         dev_dbg(bus->dev,
 699                 "SDW Slave class_id 0x%02x, mfg_id 0x%04x, part_id 0x%04x, unique_id 0x%x, version 0x%x\n",
 700                 id->class_id, id->mfg_id, id->part_id, id->unique_id, id->sdw_version);
 701 }
 702 EXPORT_SYMBOL(sdw_extract_slave_id);
 703
 704 static int sdw_program_device_num(struct sdw_bus *bus)
 705 {
 706         u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0};
 707         struct sdw_slave *slave, *_s;
 708         struct sdw_slave_id id;
 709         struct sdw_msg msg;
 710         bool found;
 711         int count = 0, ret;
 712         u64 addr;
 713
 714         /* No Slave, so use raw xfer api */
 715         ret = sdw_fill_msg(&msg, NULL, SDW_SCP_DEVID_0,
 716                            SDW_NUM_DEV_ID_REGISTERS, 0, SDW_MSG_FLAG_READ, buf);
 717         if (ret < 0)
 718                 return ret;
 719
 720         do {
 721                 ret = sdw_transfer(bus, &msg);
 722                 if (ret == -ENODATA) { /* end of device id reads */
 723                         dev_dbg(bus->dev, "No more devices to enumerate\n");
 724                         ret = 0;
 725                         break;
 726                 }
 727                 if (ret < 0) {
 728                         dev_err(bus->dev, "DEVID read fail:%d\n", ret);
 729                         break;
 730                 }
 731
 732                 /*
 733                  * Construct the addr and extract. Cast the higher shift
 734                  * bits to avoid truncation due to size limit.
 735                  */
 736                 addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) |
 737                         ((u64)buf[2] << 24) | ((u64)buf[1] << 32) |
 738                         ((u64)buf[0] << 40);
 739
 740                 sdw_extract_slave_id(bus, addr, &id);
 741
 742                 found = false;
 743                 /* Now compare with entries */
 744                 list_for_each_entry_safe(slave, _s, &bus->slaves, node) {
 745                         if (sdw_compare_devid(slave, id) == 0) {
 746                                 found = true;
 747
 748                                 /*
 749                                  * Assign a new dev_num to this Slave and
 750                                  * not mark it present. It will be marked
 751                                  * present after it reports ATTACHED on new
 752                                  * dev_num
 753                                  */
 754                                 ret = sdw_assign_device_num(slave);
 755                                 if (ret < 0) {
 756                                         dev_err(bus->dev,
 757                                                 "Assign dev_num failed:%d\n",
 758                                                 ret);
 759                                         return ret;
 760                                 }
 761
 762                                 break;
 763                         }
 764                 }
 765
 766                 if (!found) {
 767                         /* TODO: Park this device in Group 13 */
 768
 769                         /*
 770                          * add Slave device even if there is no platform
 771                          * firmware description. There will be no driver probe
 772                          * but the user/integration will be able to see the
 773                          * device, enumeration status and device number in sysfs
 774                          */
 775                         sdw_slave_add(bus, &id, NULL);
 776
 777                         dev_err(bus->dev, "Slave Entry not found\n");
 778                 }
 779
 780                 count++;
 781
 782                 /*
 783                  * Check till error out or retry (count) exhausts.
 784                  * Device can drop off and rejoin during enumeration
 785                  * so count till twice the bound.
 786                  */
 787
 788         } while (ret == 0 && count < (SDW_MAX_DEVICES * 2));
 789
 790         return ret;
 791 }
 792
 793 static void sdw_modify_slave_status(struct sdw_slave *slave,
 794                                     enum sdw_slave_status status)
 795 {
 796         struct sdw_bus *bus = slave->bus;
 797
 798         mutex_lock(&bus->bus_lock);
 799
 800         dev_vdbg(bus->dev,
 801                  "%s: changing status slave %d status %d new status %d\n",
 802                  __func__, slave->dev_num, slave->status, status);
 803
 804         if (status == SDW_SLAVE_UNATTACHED) {
 805                 dev_dbg(&slave->dev,
 806                         "%s: initializing enumeration and init completion for Slave %d\n",
 807                         __func__, slave->dev_num);
 808
 809                 init_completion(&slave->enumeration_complete);
 810                 init_completion(&slave->initialization_complete);
 811
 812         } else if ((status == SDW_SLAVE_ATTACHED) &&
 813                    (slave->status == SDW_SLAVE_UNATTACHED)) {
 814                 dev_dbg(&slave->dev,
 815                         "%s: signaling enumeration completion for Slave %d\n",
 816                         __func__, slave->dev_num);
 817
 818                 complete(&slave->enumeration_complete);
 819         }
 820         slave->status = status;
 821         mutex_unlock(&bus->bus_lock);
 822 }
 823
 824 static int sdw_slave_clk_stop_callback(struct sdw_slave *slave,
 825                                        enum sdw_clk_stop_mode mode,
 826                                        enum sdw_clk_stop_type type)
 827 {
 828         int ret;
 829
 830         if (slave->ops && slave->ops->clk_stop) {
 831                 ret = slave->ops->clk_stop(slave, mode, type);
 832                 if (ret < 0)
 833                         return ret;
 834         }
 835
 836         return 0;
 837 }
 838
 839 static int sdw_slave_clk_stop_prepare(struct sdw_slave *slave,
 840                                       enum sdw_clk_stop_mode mode,
 841                                       bool prepare)
 842 {
 843         bool wake_en;
 844         u32 val = 0;
 845         int ret;
 846
 847         wake_en = slave->prop.wake_capable;
 848
 849         if (prepare) {
 850                 val = SDW_SCP_SYSTEMCTRL_CLK_STP_PREP;
 851
 852                 if (mode == SDW_CLK_STOP_MODE1)
 853                         val |= SDW_SCP_SYSTEMCTRL_CLK_STP_MODE1;
 854
 855                 if (wake_en)
 856                         val |= SDW_SCP_SYSTEMCTRL_WAKE_UP_EN;
 857         } else {
 858                 ret = sdw_read_no_pm(slave, SDW_SCP_SYSTEMCTRL);
 859                 if (ret < 0) {
 860                         if (ret != -ENODATA)
 861                                 dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL read failed:%d\n", ret);
 862                         return ret;
 863                 }
 864                 val = ret;
 865                 val &= ~(SDW_SCP_SYSTEMCTRL_CLK_STP_PREP);
 866         }
 867
 868         ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val);
 869
 870         if (ret < 0 && ret != -ENODATA)
 871                 dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL write failed:%d\n", ret);
 872
 873         return ret;
 874 }
 875
 876 static int sdw_bus_wait_for_clk_prep_deprep(struct sdw_bus *bus, u16 dev_num)
 877 {
 878         int retry = bus->clk_stop_timeout;
 879         int val;
 880
 881         do {
 882                 val = sdw_bread_no_pm(bus, dev_num, SDW_SCP_STAT);
 883                 if (val < 0) {
 884                         dev_err(bus->dev, "SDW_SCP_STAT bread failed:%d\n", val);
 885                         return val;
 886                 }
 887                 val &= SDW_SCP_STAT_CLK_STP_NF;
 888                 if (!val) {
 889                         dev_dbg(bus->dev, "clock stop prep/de-prep done slave:%d\n",
 890                                 dev_num);
 891                         return 0;
 892                 }
 893
 894                 usleep_range(1000, 1500);
 895                 retry--;
 896         } while (retry);
 897
 898         dev_err(bus->dev, "clock stop prep/de-prep failed slave:%d\n",
 899                 dev_num);
 900
 901         return -ETIMEDOUT;
 902 }
 903
 904 /**
 905  * sdw_bus_prep_clk_stop: prepare Slave(s) for clock stop
 906  *
 907  * @bus: SDW bus instance
 908  *
 909  * Query Slave for clock stop mode and prepare for that mode.
 910  */
 911 int sdw_bus_prep_clk_stop(struct sdw_bus *bus)
 912 {
 913         bool simple_clk_stop = true;
 914         struct sdw_slave *slave;
 915         bool is_slave = false;
 916         int ret = 0;
 917
 918         /*
 919          * In order to save on transition time, prepare
 920          * each Slave and then wait for all Slave(s) to be
 921          * prepared for clock stop.
 922          * If one of the Slave devices has lost sync and
 923          * replies with Command Ignored/-ENODATA, we continue
 924          * the loop
 925          */
 926         list_for_each_entry(slave, &bus->slaves, node) {
 927                 if (!slave->dev_num)
 928                         continue;
 929
 930                 if (slave->status != SDW_SLAVE_ATTACHED &&
 931                     slave->status != SDW_SLAVE_ALERT)
 932                         continue;
 933
 934                 /* Identify if Slave(s) are available on Bus */
 935                 is_slave = true;
 936
 937                 ret = sdw_slave_clk_stop_callback(slave,
 938                                                   SDW_CLK_STOP_MODE0,
 939                                                   SDW_CLK_PRE_PREPARE);
 940                 if (ret < 0 && ret != -ENODATA) {
 941                         dev_err(&slave->dev, "clock stop pre-prepare cb failed:%d\n", ret);
 942                         return ret;
 943                 }
 944
 945                 /* Only prepare a Slave device if needed */
 946                 if (!slave->prop.simple_clk_stop_capable) {
 947                         simple_clk_stop = false;
 948
 949                         ret = sdw_slave_clk_stop_prepare(slave,
 950                                                          SDW_CLK_STOP_MODE0,
 951                                                          true);
 952                         if (ret < 0 && ret != -ENODATA) {
 953                                 dev_err(&slave->dev, "clock stop prepare failed:%d\n", ret);
 954                                 return ret;
 955                         }
 956                 }
 957         }
 958
 959         /* Skip remaining clock stop preparation if no Slave is attached */
 960         if (!is_slave)
 961                 return 0;
 962
 963         /*
 964          * Don't wait for all Slaves to be ready if they follow the simple
 965          * state machine
 966          */
 967         if (!simple_clk_stop) {
 968                 ret = sdw_bus_wait_for_clk_prep_deprep(bus,
 969                                                        SDW_BROADCAST_DEV_NUM);
 970                 /*
 971                  * if there are no Slave devices present and the reply is
 972                  * Command_Ignored/-ENODATA, we don't need to continue with the
 973                  * flow and can just return here. The error code is not modified
 974                  * and its handling left as an exercise for the caller.
 975                  */
 976                 if (ret < 0)
 977                         return ret;
 978         }
 979
 980         /* Inform slaves that prep is done */
 981         list_for_each_entry(slave, &bus->slaves, node) {
 982                 if (!slave->dev_num)
 983                         continue;
 984
 985                 if (slave->status != SDW_SLAVE_ATTACHED &&
 986                     slave->status != SDW_SLAVE_ALERT)
 987                         continue;
 988
 989                 ret = sdw_slave_clk_stop_callback(slave,
 990                                                   SDW_CLK_STOP_MODE0,
 991                                                   SDW_CLK_POST_PREPARE);
 992
 993                 if (ret < 0 && ret != -ENODATA) {
 994                         dev_err(&slave->dev, "clock stop post-prepare cb failed:%d\n", ret);
 995                         return ret;
 996                 }
 997         }
 998
 999         return 0;
1000 }
1001 EXPORT_SYMBOL(sdw_bus_prep_clk_stop);
1002
1003 /**
1004  * sdw_bus_clk_stop: stop bus clock
1005  *
1006  * @bus: SDW bus instance
1007  *
1008  * After preparing the Slaves for clock stop, stop the clock by broadcasting
1009  * write to SCP_CTRL register.
1010  */
1011 int sdw_bus_clk_stop(struct sdw_bus *bus)
1012 {
1013         int ret;
1014
1015         /*
1016          * broadcast clock stop now, attached Slaves will ACK this,
1017          * unattached will ignore
1018          */
1019         ret = sdw_bwrite_no_pm(bus, SDW_BROADCAST_DEV_NUM,
1020                                SDW_SCP_CTRL, SDW_SCP_CTRL_CLK_STP_NOW);
1021         if (ret < 0) {
1022                 if (ret != -ENODATA)
1023                         dev_err(bus->dev, "ClockStopNow Broadcast msg failed %d\n", ret);
1024                 return ret;
1025         }
1026
1027         return 0;
1028 }
1029 EXPORT_SYMBOL(sdw_bus_clk_stop);
1030
1031 /**
1032  * sdw_bus_exit_clk_stop: Exit clock stop mode
1033  *
1034  * @bus: SDW bus instance
1035  *
1036  * This De-prepares the Slaves by exiting Clock Stop Mode 0. For the Slaves
1037  * exiting Clock Stop Mode 1, they will be de-prepared after they enumerate
1038  * back.
1039  */
1040 int sdw_bus_exit_clk_stop(struct sdw_bus *bus)
1041 {
1042         bool simple_clk_stop = true;
1043         struct sdw_slave *slave;
1044         bool is_slave = false;
1045         int ret;
1046
1047         /*
1048          * In order to save on transition time, de-prepare
1049          * each Slave and then wait for all Slave(s) to be
1050          * de-prepared after clock resume.
1051          */
1052         list_for_each_entry(slave, &bus->slaves, node) {
1053                 if (!slave->dev_num)
1054                         continue;
1055
1056                 if (slave->status != SDW_SLAVE_ATTACHED &&
1057                     slave->status != SDW_SLAVE_ALERT)
1058                         continue;
1059
1060                 /* Identify if Slave(s) are available on Bus */
1061                 is_slave = true;
1062
1063                 ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1064                                                   SDW_CLK_PRE_DEPREPARE);
1065                 if (ret < 0)
1066                         dev_warn(&slave->dev, "clock stop pre-deprepare cb failed:%d\n", ret);
1067
1068                 /* Only de-prepare a Slave device if needed */
1069                 if (!slave->prop.simple_clk_stop_capable) {
1070                         simple_clk_stop = false;
1071
1072                         ret = sdw_slave_clk_stop_prepare(slave, SDW_CLK_STOP_MODE0,
1073                                                          false);
1074
1075                         if (ret < 0)
1076                                 dev_warn(&slave->dev, "clock stop deprepare failed:%d\n", ret);
1077                 }
1078         }
1079
1080         /* Skip remaining clock stop de-preparation if no Slave is attached */
1081         if (!is_slave)
1082                 return 0;
1083
1084         /*
1085          * Don't wait for all Slaves to be ready if they follow the simple
1086          * state machine
1087          */
1088         if (!simple_clk_stop) {
1089                 ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM);
1090                 if (ret < 0)
1091                         dev_warn(&slave->dev, "clock stop deprepare wait failed:%d\n", ret);
1092         }
1093
1094         list_for_each_entry(slave, &bus->slaves, node) {
1095                 if (!slave->dev_num)
1096                         continue;
1097
1098                 if (slave->status != SDW_SLAVE_ATTACHED &&
1099                     slave->status != SDW_SLAVE_ALERT)
1100                         continue;
1101
1102                 ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1103                                                   SDW_CLK_POST_DEPREPARE);
1104                 if (ret < 0)
1105                         dev_warn(&slave->dev, "clock stop post-deprepare cb failed:%d\n", ret);
1106         }
1107
1108         return 0;
1109 }
1110 EXPORT_SYMBOL(sdw_bus_exit_clk_stop);
1111
1112 int sdw_configure_dpn_intr(struct sdw_slave *slave,
1113                            int port, bool enable, int mask)
1114 {
1115         u32 addr;
1116         int ret;
1117         u8 val = 0;
1118
1119         if (slave->bus->params.s_data_mode != SDW_PORT_DATA_MODE_NORMAL) {
1120                 dev_dbg(&slave->dev, "TEST FAIL interrupt %s\n",
1121                         enable ? "on" : "off");
1122                 mask |= SDW_DPN_INT_TEST_FAIL;
1123         }
1124
1125         addr = SDW_DPN_INTMASK(port);
1126
1127         /* Set/Clear port ready interrupt mask */
1128         if (enable) {
1129                 val |= mask;
1130                 val |= SDW_DPN_INT_PORT_READY;
1131         } else {
1132                 val &= ~(mask);
1133                 val &= ~SDW_DPN_INT_PORT_READY;
1134         }
1135
1136         ret = sdw_update(slave, addr, (mask | SDW_DPN_INT_PORT_READY), val);
1137         if (ret < 0)
1138                 dev_err(&slave->dev,
1139                         "SDW_DPN_INTMASK write failed:%d\n", val);
1140
1141         return ret;
1142 }
1143
1144 static int sdw_slave_set_frequency(struct sdw_slave *slave)
1145 {
1146         u32 mclk_freq = slave->bus->prop.mclk_freq;
1147         u32 curr_freq = slave->bus->params.curr_dr_freq >> 1;
1148         unsigned int scale;
1149         u8 scale_index;
1150         u8 base;
1151         int ret;
1152
1153         /*
1154          * frequency base and scale registers are required for SDCA
1155          * devices. They may also be used for 1.2+/non-SDCA devices,
1156          * but we will need a DisCo property to cover this case
1157          */
1158         if (!slave->id.class_id)
1159                 return 0;
1160
1161         if (!mclk_freq) {
1162                 dev_err(&slave->dev,
1163                         "no bus MCLK, cannot set SDW_SCP_BUS_CLOCK_BASE\n");
1164                 return -EINVAL;
1165         }
1166
1167         /*
1168          * map base frequency using Table 89 of SoundWire 1.2 spec.
1169          * The order of the tests just follows the specification, this
1170          * is not a selection between possible values or a search for
1171          * the best value but just a mapping.  Only one case per platform
1172          * is relevant.
1173          * Some BIOS have inconsistent values for mclk_freq but a
1174          * correct root so we force the mclk_freq to avoid variations.
1175          */
1176         if (!(19200000 % mclk_freq)) {
1177                 mclk_freq = 19200000;
1178                 base = SDW_SCP_BASE_CLOCK_19200000_HZ;
1179         } else if (!(24000000 % mclk_freq)) {
1180                 mclk_freq = 24000000;
1181                 base = SDW_SCP_BASE_CLOCK_24000000_HZ;
1182         } else if (!(24576000 % mclk_freq)) {
1183                 mclk_freq = 24576000;
1184                 base = SDW_SCP_BASE_CLOCK_24576000_HZ;
1185         } else if (!(22579200 % mclk_freq)) {
1186                 mclk_freq = 22579200;
1187                 base = SDW_SCP_BASE_CLOCK_22579200_HZ;
1188         } else if (!(32000000 % mclk_freq)) {
1189                 mclk_freq = 32000000;
1190                 base = SDW_SCP_BASE_CLOCK_32000000_HZ;
1191         } else {
1192                 dev_err(&slave->dev,
1193                         "Unsupported clock base, mclk %d\n",
1194                         mclk_freq);
1195                 return -EINVAL;
1196         }
1197
1198         if (mclk_freq % curr_freq) {
1199                 dev_err(&slave->dev,
1200                         "mclk %d is not multiple of bus curr_freq %d\n",
1201                         mclk_freq, curr_freq);
1202                 return -EINVAL;
1203         }
1204
1205         scale = mclk_freq / curr_freq;
1206
1207         /*
1208          * map scale to Table 90 of SoundWire 1.2 spec - and check
1209          * that the scale is a power of two and maximum 64
1210          */
1211         scale_index = ilog2(scale);
1212
1213         if (BIT(scale_index) != scale || scale_index > 6) {
1214                 dev_err(&slave->dev,
1215                         "No match found for scale %d, bus mclk %d curr_freq %d\n",
1216                         scale, mclk_freq, curr_freq);
1217                 return -EINVAL;
1218         }
1219         scale_index++;
1220
1221         ret = sdw_write_no_pm(slave, SDW_SCP_BUS_CLOCK_BASE, base);
1222         if (ret < 0) {
1223                 dev_err(&slave->dev,
1224                         "SDW_SCP_BUS_CLOCK_BASE write failed:%d\n", ret);
1225                 return ret;
1226         }
1227
1228         /* initialize scale for both banks */
1229         ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B0, scale_index);
1230         if (ret < 0) {
1231                 dev_err(&slave->dev,
1232                         "SDW_SCP_BUSCLOCK_SCALE_B0 write failed:%d\n", ret);
1233                 return ret;
1234         }
1235         ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B1, scale_index);
1236         if (ret < 0)
1237                 dev_err(&slave->dev,
1238                         "SDW_SCP_BUSCLOCK_SCALE_B1 write failed:%d\n", ret);
1239
1240         dev_dbg(&slave->dev,
1241                 "Configured bus base %d, scale %d, mclk %d, curr_freq %d\n",
1242                 base, scale_index, mclk_freq, curr_freq);
1243
1244         return ret;
1245 }
1246
1247 static int sdw_initialize_slave(struct sdw_slave *slave)
1248 {
1249         struct sdw_slave_prop *prop = &slave->prop;
1250         int status;
1251         int ret;
1252         u8 val;
1253
1254         ret = sdw_slave_set_frequency(slave);
1255         if (ret < 0)
1256                 return ret;
1257
1258         if (slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH) {
1259                 /* Clear bus clash interrupt before enabling interrupt mask */
1260                 status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1261                 if (status < 0) {
1262                         dev_err(&slave->dev,
1263                                 "SDW_SCP_INT1 (BUS_CLASH) read failed:%d\n", status);
1264                         return status;
1265                 }
1266                 if (status & SDW_SCP_INT1_BUS_CLASH) {
1267                         dev_warn(&slave->dev, "Bus clash detected before INT mask is enabled\n");
1268                         ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_BUS_CLASH);
1269                         if (ret < 0) {
1270                                 dev_err(&slave->dev,
1271                                         "SDW_SCP_INT1 (BUS_CLASH) write failed:%d\n", ret);
1272                                 return ret;
1273                         }
1274                 }
1275         }
1276         if ((slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY) &&
1277             !(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY)) {
1278                 /* Clear parity interrupt before enabling interrupt mask */
1279                 status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1280                 if (status < 0) {
1281                         dev_err(&slave->dev,
1282                                 "SDW_SCP_INT1 (PARITY) read failed:%d\n", status);
1283                         return status;
1284                 }
1285                 if (status & SDW_SCP_INT1_PARITY) {
1286                         dev_warn(&slave->dev, "PARITY error detected before INT mask is enabled\n");
1287                         ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_PARITY);
1288                         if (ret < 0) {
1289                                 dev_err(&slave->dev,
1290                                         "SDW_SCP_INT1 (PARITY) write failed:%d\n", ret);
1291                                 return ret;
1292                         }
1293                 }
1294         }
1295
1296         /*
1297          * Set SCP_INT1_MASK register, typically bus clash and
1298          * implementation-defined interrupt mask. The Parity detection
1299          * may not always be correct on startup so its use is
1300          * device-dependent, it might e.g. only be enabled in
1301          * steady-state after a couple of frames.
1302          */
1303         val = slave->prop.scp_int1_mask;
1304
1305         /* Enable SCP interrupts */
1306         ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val);
1307         if (ret < 0) {
1308                 dev_err(&slave->dev,
1309                         "SDW_SCP_INTMASK1 write failed:%d\n", ret);
1310                 return ret;
1311         }
1312
1313         /* No need to continue if DP0 is not present */
1314         if (!slave->prop.dp0_prop)
1315                 return 0;
1316
1317         /* Enable DP0 interrupts */
1318         val = prop->dp0_prop->imp_def_interrupts;
1319         val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE;
1320
1321         ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val);
1322         if (ret < 0)
1323                 dev_err(&slave->dev,
1324                         "SDW_DP0_INTMASK read failed:%d\n", ret);
1325         return ret;
1326 }
1327
1328 static int sdw_handle_dp0_interrupt(struct sdw_slave *slave, u8 *slave_status)
1329 {
1330         u8 clear, impl_int_mask;
1331         int status, status2, ret, count = 0;
1332
1333         status = sdw_read_no_pm(slave, SDW_DP0_INT);
1334         if (status < 0) {
1335                 dev_err(&slave->dev,
1336                         "SDW_DP0_INT read failed:%d\n", status);
1337                 return status;
1338         }
1339
1340         do {
1341                 clear = status & ~SDW_DP0_INTERRUPTS;
1342
1343                 if (status & SDW_DP0_INT_TEST_FAIL) {
1344                         dev_err(&slave->dev, "Test fail for port 0\n");
1345                         clear |= SDW_DP0_INT_TEST_FAIL;
1346                 }
1347
1348                 /*
1349                  * Assumption: PORT_READY interrupt will be received only for
1350                  * ports implementing Channel Prepare state machine (CP_SM)
1351                  */
1352
1353                 if (status & SDW_DP0_INT_PORT_READY) {
1354                         complete(&slave->port_ready[0]);
1355                         clear |= SDW_DP0_INT_PORT_READY;
1356                 }
1357
1358                 if (status & SDW_DP0_INT_BRA_FAILURE) {
1359                         dev_err(&slave->dev, "BRA failed\n");
1360                         clear |= SDW_DP0_INT_BRA_FAILURE;
1361                 }
1362
1363                 impl_int_mask = SDW_DP0_INT_IMPDEF1 |
1364                         SDW_DP0_INT_IMPDEF2 | SDW_DP0_INT_IMPDEF3;
1365
1366                 if (status & impl_int_mask) {
1367                         clear |= impl_int_mask;
1368                         *slave_status = clear;
1369                 }
1370
1371                 /* clear the interrupts but don't touch reserved and SDCA_CASCADE fields */
1372                 ret = sdw_write_no_pm(slave, SDW_DP0_INT, clear);
1373                 if (ret < 0) {
1374                         dev_err(&slave->dev,
1375                                 "SDW_DP0_INT write failed:%d\n", ret);
1376                         return ret;
1377                 }
1378
1379                 /* Read DP0 interrupt again */
1380                 status2 = sdw_read_no_pm(slave, SDW_DP0_INT);
1381                 if (status2 < 0) {
1382                         dev_err(&slave->dev,
1383                                 "SDW_DP0_INT read failed:%d\n", status2);
1384                         return status2;
1385                 }
1386                 /* filter to limit loop to interrupts identified in the first status read */
1387                 status &= status2;
1388
1389                 count++;
1390
1391                 /* we can get alerts while processing so keep retrying */
1392         } while ((status & SDW_DP0_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1393
1394         if (count == SDW_READ_INTR_CLEAR_RETRY)
1395                 dev_warn(&slave->dev, "Reached MAX_RETRY on DP0 read\n");
1396
1397         return ret;
1398 }
1399
1400 static int sdw_handle_port_interrupt(struct sdw_slave *slave,
1401                                      int port, u8 *slave_status)
1402 {
1403         u8 clear, impl_int_mask;
1404         int status, status2, ret, count = 0;
1405         u32 addr;
1406
1407         if (port == 0)
1408                 return sdw_handle_dp0_interrupt(slave, slave_status);
1409
1410         addr = SDW_DPN_INT(port);
1411         status = sdw_read_no_pm(slave, addr);
1412         if (status < 0) {
1413                 dev_err(&slave->dev,
1414                         "SDW_DPN_INT read failed:%d\n", status);
1415
1416                 return status;
1417         }
1418
1419         do {
1420                 clear = status & ~SDW_DPN_INTERRUPTS;
1421
1422                 if (status & SDW_DPN_INT_TEST_FAIL) {
1423                         dev_err(&slave->dev, "Test fail for port:%d\n", port);
1424                         clear |= SDW_DPN_INT_TEST_FAIL;
1425                 }
1426
1427                 /*
1428                  * Assumption: PORT_READY interrupt will be received only
1429                  * for ports implementing CP_SM.
1430                  */
1431                 if (status & SDW_DPN_INT_PORT_READY) {
1432                         complete(&slave->port_ready[port]);
1433                         clear |= SDW_DPN_INT_PORT_READY;
1434                 }
1435
1436                 impl_int_mask = SDW_DPN_INT_IMPDEF1 |
1437                         SDW_DPN_INT_IMPDEF2 | SDW_DPN_INT_IMPDEF3;
1438
1439                 if (status & impl_int_mask) {
1440                         clear |= impl_int_mask;
1441                         *slave_status = clear;
1442                 }
1443
1444                 /* clear the interrupt but don't touch reserved fields */
1445                 ret = sdw_write_no_pm(slave, addr, clear);
1446                 if (ret < 0) {
1447                         dev_err(&slave->dev,
1448                                 "SDW_DPN_INT write failed:%d\n", ret);
1449                         return ret;
1450                 }
1451
1452                 /* Read DPN interrupt again */
1453                 status2 = sdw_read_no_pm(slave, addr);
1454                 if (status2 < 0) {
1455                         dev_err(&slave->dev,
1456                                 "SDW_DPN_INT read failed:%d\n", status2);
1457                         return status2;
1458                 }
1459                 /* filter to limit loop to interrupts identified in the first status read */
1460                 status &= status2;
1461
1462                 count++;
1463
1464                 /* we can get alerts while processing so keep retrying */
1465         } while ((status & SDW_DPN_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1466
1467         if (count == SDW_READ_INTR_CLEAR_RETRY)
1468                 dev_warn(&slave->dev, "Reached MAX_RETRY on port read");
1469
1470         return ret;
1471 }
1472
1473 static int sdw_handle_slave_alerts(struct sdw_slave *slave)
1474 {
1475         struct sdw_slave_intr_status slave_intr;
1476         u8 clear = 0, bit, port_status[15] = {0};
1477         int port_num, stat, ret, count = 0;
1478         unsigned long port;
1479         bool slave_notify;
1480         u8 sdca_cascade = 0;
1481         u8 buf, buf2[2], _buf, _buf2[2];
1482         bool parity_check;
1483         bool parity_quirk;
1484
1485         sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);
1486
1487         ret = pm_runtime_get_sync(&slave->dev);
1488         if (ret < 0 && ret != -EACCES) {
1489                 dev_err(&slave->dev, "Failed to resume device: %d\n", ret);
1490                 pm_runtime_put_noidle(&slave->dev);
1491                 return ret;
1492         }
1493
1494         /* Read Intstat 1, Intstat 2 and Intstat 3 registers */
1495         ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1496         if (ret < 0) {
1497                 dev_err(&slave->dev,
1498                         "SDW_SCP_INT1 read failed:%d\n", ret);
1499                 goto io_err;
1500         }
1501         buf = ret;
1502
1503         ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2);
1504         if (ret < 0) {
1505                 dev_err(&slave->dev,
1506                         "SDW_SCP_INT2/3 read failed:%d\n", ret);
1507                 goto io_err;
1508         }
1509
1510         if (slave->prop.is_sdca) {
1511                 ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1512                 if (ret < 0) {
1513                         dev_err(&slave->dev,
1514                                 "SDW_DP0_INT read failed:%d\n", ret);
1515                         goto io_err;
1516                 }
1517                 sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1518         }
1519
1520         do {
1521                 slave_notify = false;
1522
1523                 /*
1524                  * Check parity, bus clash and Slave (impl defined)
1525                  * interrupt
1526                  */
1527                 if (buf & SDW_SCP_INT1_PARITY) {
1528                         parity_check = slave->prop.scp_int1_mask & SDW_SCP_INT1_PARITY;
1529                         parity_quirk = !slave->first_interrupt_done &&
1530                                 (slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY);
1531
1532                         if (parity_check && !parity_quirk)
1533                                 dev_err(&slave->dev, "Parity error detected\n");
1534                         clear |= SDW_SCP_INT1_PARITY;
1535                 }
1536
1537                 if (buf & SDW_SCP_INT1_BUS_CLASH) {
1538                         if (slave->prop.scp_int1_mask & SDW_SCP_INT1_BUS_CLASH)
1539                                 dev_err(&slave->dev, "Bus clash detected\n");
1540                         clear |= SDW_SCP_INT1_BUS_CLASH;
1541                 }
1542
1543                 /*
1544                  * When bus clash or parity errors are detected, such errors
1545                  * are unlikely to be recoverable errors.
1546                  * TODO: In such scenario, reset bus. Make this configurable
1547                  * via sysfs property with bus reset being the default.
1548                  */
1549
1550                 if (buf & SDW_SCP_INT1_IMPL_DEF) {
1551                         if (slave->prop.scp_int1_mask & SDW_SCP_INT1_IMPL_DEF) {
1552                                 dev_dbg(&slave->dev, "Slave impl defined interrupt\n");
1553                                 slave_notify = true;
1554                         }
1555                         clear |= SDW_SCP_INT1_IMPL_DEF;
1556                 }
1557
1558                 /* the SDCA interrupts are cleared in the codec driver .interrupt_callback() */
1559                 if (sdca_cascade)
1560                         slave_notify = true;
1561
1562                 /* Check port 0 - 3 interrupts */
1563                 port = buf & SDW_SCP_INT1_PORT0_3;
1564
1565                 /* To get port number corresponding to bits, shift it */
1566                 port = FIELD_GET(SDW_SCP_INT1_PORT0_3, port);
1567                 for_each_set_bit(bit, &port, 8) {
1568                         sdw_handle_port_interrupt(slave, bit,
1569                                                   &port_status[bit]);
1570                 }
1571
1572                 /* Check if cascade 2 interrupt is present */
1573                 if (buf & SDW_SCP_INT1_SCP2_CASCADE) {
1574                         port = buf2[0] & SDW_SCP_INTSTAT2_PORT4_10;
1575                         for_each_set_bit(bit, &port, 8) {
1576                                 /* scp2 ports start from 4 */
1577                                 port_num = bit + 3;
1578                                 sdw_handle_port_interrupt(slave,
1579                                                 port_num,
1580                                                 &port_status[port_num]);
1581                         }
1582                 }
1583
1584                 /* now check last cascade */
1585                 if (buf2[0] & SDW_SCP_INTSTAT2_SCP3_CASCADE) {
1586                         port = buf2[1] & SDW_SCP_INTSTAT3_PORT11_14;
1587                         for_each_set_bit(bit, &port, 8) {
1588                                 /* scp3 ports start from 11 */
1589                                 port_num = bit + 10;
1590                                 sdw_handle_port_interrupt(slave,
1591                                                 port_num,
1592                                                 &port_status[port_num]);
1593                         }
1594                 }
1595
1596                 /* Update the Slave driver */
1597                 if (slave_notify && slave->ops &&
1598                     slave->ops->interrupt_callback) {
1599                         slave_intr.sdca_cascade = sdca_cascade;
1600                         slave_intr.control_port = clear;
1601                         memcpy(slave_intr.port, &port_status,
1602                                sizeof(slave_intr.port));
1603
1604                         slave->ops->interrupt_callback(slave, &slave_intr);
1605                 }
1606
1607                 /* Ack interrupt */
1608                 ret = sdw_write_no_pm(slave, SDW_SCP_INT1, clear);
1609                 if (ret < 0) {
1610                         dev_err(&slave->dev,
1611                                 "SDW_SCP_INT1 write failed:%d\n", ret);
1612                         goto io_err;
1613                 }
1614
1615                 /* at this point all initial interrupt sources were handled */
1616                 slave->first_interrupt_done = true;
1617
1618                 /*
1619                  * Read status again to ensure no new interrupts arrived
1620                  * while servicing interrupts.
1621                  */
1622                 ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1623                 if (ret < 0) {
1624                         dev_err(&slave->dev,
1625                                 "SDW_SCP_INT1 recheck read failed:%d\n", ret);
1626                         goto io_err;
1627                 }
1628                 _buf = ret;
1629
1630                 ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, _buf2);
1631                 if (ret < 0) {
1632                         dev_err(&slave->dev,
1633                                 "SDW_SCP_INT2/3 recheck read failed:%d\n", ret);
1634                         goto io_err;
1635                 }
1636
1637                 if (slave->prop.is_sdca) {
1638                         ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1639                         if (ret < 0) {
1640                                 dev_err(&slave->dev,
1641                                         "SDW_DP0_INT recheck read failed:%d\n", ret);
1642                                 goto io_err;
1643                         }
1644                         sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1645                 }
1646
1647                 /*
1648                  * Make sure no interrupts are pending, but filter to limit loop
1649                  * to interrupts identified in the first status read
1650                  */
1651                 buf &= _buf;
1652                 buf2[0] &= _buf2[0];
1653                 buf2[1] &= _buf2[1];
1654                 stat = buf || buf2[0] || buf2[1] || sdca_cascade;
1655
1656                 /*
1657                  * Exit loop if Slave is continuously in ALERT state even
1658                  * after servicing the interrupt multiple times.
1659                  */
1660                 count++;
1661
1662                 /* we can get alerts while processing so keep retrying */
1663         } while (stat != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
1664
1665         if (count == SDW_READ_INTR_CLEAR_RETRY)
1666                 dev_warn(&slave->dev, "Reached MAX_RETRY on alert read\n");
1667
1668 io_err:
1669         pm_runtime_mark_last_busy(&slave->dev);
1670         pm_runtime_put_autosuspend(&slave->dev);
1671
1672         return ret;
1673 }
1674
1675 static int sdw_update_slave_status(struct sdw_slave *slave,
1676                                    enum sdw_slave_status status)
1677 {
1678         unsigned long time;
1679
1680         if (!slave->probed) {
1681                 /*
1682                  * the slave status update is typically handled in an
1683                  * interrupt thread, which can race with the driver
1684                  * probe, e.g. when a module needs to be loaded.
1685                  *
1686                  * make sure the probe is complete before updating
1687                  * status.
1688                  */
1689                 time = wait_for_completion_timeout(&slave->probe_complete,
1690                                 msecs_to_jiffies(DEFAULT_PROBE_TIMEOUT));
1691                 if (!time) {
1692                         dev_err(&slave->dev, "Probe not complete, timed out\n");
1693                         return -ETIMEDOUT;
1694                 }
1695         }
1696
1697         if (!slave->ops || !slave->ops->update_status)
1698                 return 0;
1699
1700         return slave->ops->update_status(slave, status);
1701 }
1702
1703 /**
1704  * sdw_handle_slave_status() - Handle Slave status
1705  * @bus: SDW bus instance
1706  * @status: Status for all Slave(s)
1707  */
1708 int sdw_handle_slave_status(struct sdw_bus *bus,
1709                             enum sdw_slave_status status[])
1710 {
1711         enum sdw_slave_status prev_status;
1712         struct sdw_slave *slave;
1713         bool attached_initializing;
1714         int i, ret = 0;
1715
1716         /* first check if any Slaves fell off the bus */
1717         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1718                 mutex_lock(&bus->bus_lock);
1719                 if (test_bit(i, bus->assigned) == false) {
1720                         mutex_unlock(&bus->bus_lock);
1721                         continue;
1722                 }
1723                 mutex_unlock(&bus->bus_lock);
1724
1725                 slave = sdw_get_slave(bus, i);
1726                 if (!slave)
1727                         continue;
1728
1729                 if (status[i] == SDW_SLAVE_UNATTACHED &&
1730                     slave->status != SDW_SLAVE_UNATTACHED)
1731                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1732         }
1733
1734         if (status[0] == SDW_SLAVE_ATTACHED) {
1735                 dev_dbg(bus->dev, "Slave attached, programming device number\n");
1736                 ret = sdw_program_device_num(bus);
1737                 if (ret < 0)
1738                         dev_err(bus->dev, "Slave attach failed: %d\n", ret);
1739                 /*
1740                  * programming a device number will have side effects,
1741                  * so we deal with other devices at a later time
1742                  */
1743                 return ret;
1744         }
1745
1746         /* Continue to check other slave statuses */
1747         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1748                 mutex_lock(&bus->bus_lock);
1749                 if (test_bit(i, bus->assigned) == false) {
1750                         mutex_unlock(&bus->bus_lock);
1751                         continue;
1752                 }
1753                 mutex_unlock(&bus->bus_lock);
1754
1755                 slave = sdw_get_slave(bus, i);
1756                 if (!slave)
1757                         continue;
1758
1759                 attached_initializing = false;
1760
1761                 switch (status[i]) {
1762                 case SDW_SLAVE_UNATTACHED:
1763                         if (slave->status == SDW_SLAVE_UNATTACHED)
1764                                 break;
1765
1766                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1767                         break;
1768
1769                 case SDW_SLAVE_ALERT:
1770                         ret = sdw_handle_slave_alerts(slave);
1771                         if (ret < 0)
1772                                 dev_err(&slave->dev,
1773                                         "Slave %d alert handling failed: %d\n",
1774                                         i, ret);
1775                         break;
1776
1777                 case SDW_SLAVE_ATTACHED:
1778                         if (slave->status == SDW_SLAVE_ATTACHED)
1779                                 break;
1780
1781                         prev_status = slave->status;
1782                         sdw_modify_slave_status(slave, SDW_SLAVE_ATTACHED);
1783
1784                         if (prev_status == SDW_SLAVE_ALERT)
1785                                 break;
1786
1787                         attached_initializing = true;
1788
1789                         ret = sdw_initialize_slave(slave);
1790                         if (ret < 0)
1791                                 dev_err(&slave->dev,
1792                                         "Slave %d initialization failed: %d\n",
1793                                         i, ret);
1794
1795                         break;
1796
1797                 default:
1798                         dev_err(&slave->dev, "Invalid slave %d status:%d\n",
1799                                 i, status[i]);
1800                         break;
1801                 }
1802
1803                 ret = sdw_update_slave_status(slave, status[i]);
1804                 if (ret < 0)
1805                         dev_err(&slave->dev,
1806                                 "Update Slave status failed:%d\n", ret);
1807                 if (attached_initializing) {
1808                         dev_dbg(&slave->dev,
1809                                 "%s: signaling initialization completion for Slave %d\n",
1810                                 __func__, slave->dev_num);
1811
1812                         complete(&slave->initialization_complete);
1813                 }
1814         }
1815
1816         return ret;
1817 }
1818 EXPORT_SYMBOL(sdw_handle_slave_status);
1819
1820 void sdw_clear_slave_status(struct sdw_bus *bus, u32 request)
1821 {
1822         struct sdw_slave *slave;
1823         int i;
1824
1825         /* Check all non-zero devices */
1826         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1827                 mutex_lock(&bus->bus_lock);
1828                 if (test_bit(i, bus->assigned) == false) {
1829                         mutex_unlock(&bus->bus_lock);
1830                         continue;
1831                 }
1832                 mutex_unlock(&bus->bus_lock);
1833
1834                 slave = sdw_get_slave(bus, i);
1835                 if (!slave)
1836                         continue;
1837
1838                 if (slave->status != SDW_SLAVE_UNATTACHED) {
1839                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1840                         slave->first_interrupt_done = false;
1841                 }
1842
1843                 /* keep track of request, used in pm_runtime resume */
1844                 slave->unattach_request = request;
1845         }
1846 }
1847 EXPORT_SYMBOL(sdw_clear_slave_status);