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 <linux/soundwire/sdw_type.h>
  11 #include "bus.h"
  12 #include "sysfs_local.h"
  13
  14 static DEFINE_IDA(sdw_ida);
  15
  16 static int sdw_get_id(struct sdw_bus *bus)
  17 {
  18         int rc = ida_alloc(&sdw_ida, GFP_KERNEL);
  19
  20         if (rc < 0)
  21                 return rc;
  22
  23         bus->id = rc;
  24         return 0;
  25 }
  26
  27 /**
  28  * sdw_bus_master_add() - add a bus Master instance
  29  * @bus: bus instance
  30  * @parent: parent device
  31  * @fwnode: firmware node handle
  32  *
  33  * Initializes the bus instance, read properties and create child
  34  * devices.
  35  */
  36 int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent,
  37                        struct fwnode_handle *fwnode)
  38 {
  39         struct sdw_master_prop *prop = NULL;
  40         int ret;
  41
  42         if (!parent) {
  43                 pr_err("SoundWire parent device is not set\n");
  44                 return -ENODEV;
  45         }
  46
  47         ret = sdw_get_id(bus);
  48         if (ret < 0) {
  49                 dev_err(parent, "Failed to get bus id\n");
  50                 return ret;
  51         }
  52
  53         ret = sdw_master_device_add(bus, parent, fwnode);
  54         if (ret < 0) {
  55                 dev_err(parent, "Failed to add master device at link %d\n",
  56                         bus->link_id);
  57                 return ret;
  58         }
  59
  60         if (!bus->ops) {
  61                 dev_err(bus->dev, "SoundWire Bus ops are not set\n");
  62                 return -EINVAL;
  63         }
  64
  65         if (!bus->compute_params) {
  66                 dev_err(bus->dev,
  67                         "Bandwidth allocation not configured, compute_params no set\n");
  68                 return -EINVAL;
  69         }
  70
  71         mutex_init(&bus->msg_lock);
  72         mutex_init(&bus->bus_lock);
  73         INIT_LIST_HEAD(&bus->slaves);
  74         INIT_LIST_HEAD(&bus->m_rt_list);
  75
  76         /*
  77          * Initialize multi_link flag
  78          * TODO: populate this flag by reading property from FW node
  79          */
  80         bus->multi_link = false;
  81         if (bus->ops->read_prop) {
  82                 ret = bus->ops->read_prop(bus);
  83                 if (ret < 0) {
  84                         dev_err(bus->dev,
  85                                 "Bus read properties failed:%d\n", ret);
  86                         return ret;
  87                 }
  88         }
  89
  90         sdw_bus_debugfs_init(bus);
  91
  92         /*
  93          * Device numbers in SoundWire are 0 through 15. Enumeration device
  94          * number (0), Broadcast device number (15), Group numbers (12 and
  95          * 13) and Master device number (14) are not used for assignment so
  96          * mask these and other higher bits.
  97          */
  98
  99         /* Set higher order bits */
 100         *bus->assigned = ~GENMASK(SDW_BROADCAST_DEV_NUM, SDW_ENUM_DEV_NUM);
 101
 102         /* Set enumuration device number and broadcast device number */
 103         set_bit(SDW_ENUM_DEV_NUM, bus->assigned);
 104         set_bit(SDW_BROADCAST_DEV_NUM, bus->assigned);
 105
 106         /* Set group device numbers and master device number */
 107         set_bit(SDW_GROUP12_DEV_NUM, bus->assigned);
 108         set_bit(SDW_GROUP13_DEV_NUM, bus->assigned);
 109         set_bit(SDW_MASTER_DEV_NUM, bus->assigned);
 110
 111         /*
 112          * SDW is an enumerable bus, but devices can be powered off. So,
 113          * they won't be able to report as present.
 114          *
 115          * Create Slave devices based on Slaves described in
 116          * the respective firmware (ACPI/DT)
 117          */
 118         if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev))
 119                 ret = sdw_acpi_find_slaves(bus);
 120         else if (IS_ENABLED(CONFIG_OF) && bus->dev->of_node)
 121                 ret = sdw_of_find_slaves(bus);
 122         else
 123                 ret = -ENOTSUPP; /* No ACPI/DT so error out */
 124
 125         if (ret < 0) {
 126                 dev_err(bus->dev, "Finding slaves failed:%d\n", ret);
 127                 return ret;
 128         }
 129
 130         /*
 131          * Initialize clock values based on Master properties. The max
 132          * frequency is read from max_clk_freq property. Current assumption
 133          * is that the bus will start at highest clock frequency when
 134          * powered on.
 135          *
 136          * Default active bank will be 0 as out of reset the Slaves have
 137          * to start with bank 0 (Table 40 of Spec)
 138          */
 139         prop = &bus->prop;
 140         bus->params.max_dr_freq = prop->max_clk_freq * SDW_DOUBLE_RATE_FACTOR;
 141         bus->params.curr_dr_freq = bus->params.max_dr_freq;
 142         bus->params.curr_bank = SDW_BANK0;
 143         bus->params.next_bank = SDW_BANK1;
 144
 145         return 0;
 146 }
 147 EXPORT_SYMBOL(sdw_bus_master_add);
 148
 149 static int sdw_delete_slave(struct device *dev, void *data)
 150 {
 151         struct sdw_slave *slave = dev_to_sdw_dev(dev);
 152         struct sdw_bus *bus = slave->bus;
 153
 154         pm_runtime_disable(dev);
 155
 156         sdw_slave_debugfs_exit(slave);
 157
 158         mutex_lock(&bus->bus_lock);
 159
 160         if (slave->dev_num) /* clear dev_num if assigned */
 161                 clear_bit(slave->dev_num, bus->assigned);
 162
 163         list_del_init(&slave->node);
 164         mutex_unlock(&bus->bus_lock);
 165
 166         device_unregister(dev);
 167         return 0;
 168 }
 169
 170 /**
 171  * sdw_bus_master_delete() - delete the bus master instance
 172  * @bus: bus to be deleted
 173  *
 174  * Remove the instance, delete the child devices.
 175  */
 176 void sdw_bus_master_delete(struct sdw_bus *bus)
 177 {
 178         device_for_each_child(bus->dev, NULL, sdw_delete_slave);
 179         sdw_master_device_del(bus);
 180
 181         sdw_bus_debugfs_exit(bus);
 182         ida_free(&sdw_ida, bus->id);
 183 }
 184 EXPORT_SYMBOL(sdw_bus_master_delete);
 185
 186 /*
 187  * SDW IO Calls
 188  */
 189
 190 static inline int find_response_code(enum sdw_command_response resp)
 191 {
 192         switch (resp) {
 193         case SDW_CMD_OK:
 194                 return 0;
 195
 196         case SDW_CMD_IGNORED:
 197                 return -ENODATA;
 198
 199         case SDW_CMD_TIMEOUT:
 200                 return -ETIMEDOUT;
 201
 202         default:
 203                 return -EIO;
 204         }
 205 }
 206
 207 static inline int do_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 208 {
 209         int retry = bus->prop.err_threshold;
 210         enum sdw_command_response resp;
 211         int ret = 0, i;
 212
 213         for (i = 0; i <= retry; i++) {
 214                 resp = bus->ops->xfer_msg(bus, msg);
 215                 ret = find_response_code(resp);
 216
 217                 /* if cmd is ok or ignored return */
 218                 if (ret == 0 || ret == -ENODATA)
 219                         return ret;
 220         }
 221
 222         return ret;
 223 }
 224
 225 static inline int do_transfer_defer(struct sdw_bus *bus,
 226                                     struct sdw_msg *msg,
 227                                     struct sdw_defer *defer)
 228 {
 229         int retry = bus->prop.err_threshold;
 230         enum sdw_command_response resp;
 231         int ret = 0, i;
 232
 233         defer->msg = msg;
 234         defer->length = msg->len;
 235         init_completion(&defer->complete);
 236
 237         for (i = 0; i <= retry; i++) {
 238                 resp = bus->ops->xfer_msg_defer(bus, msg, defer);
 239                 ret = find_response_code(resp);
 240                 /* if cmd is ok or ignored return */
 241                 if (ret == 0 || ret == -ENODATA)
 242                         return ret;
 243         }
 244
 245         return ret;
 246 }
 247
 248 static int sdw_reset_page(struct sdw_bus *bus, u16 dev_num)
 249 {
 250         int retry = bus->prop.err_threshold;
 251         enum sdw_command_response resp;
 252         int ret = 0, i;
 253
 254         for (i = 0; i <= retry; i++) {
 255                 resp = bus->ops->reset_page_addr(bus, dev_num);
 256                 ret = find_response_code(resp);
 257                 /* if cmd is ok or ignored return */
 258                 if (ret == 0 || ret == -ENODATA)
 259                         return ret;
 260         }
 261
 262         return ret;
 263 }
 264
 265 static int sdw_transfer_unlocked(struct sdw_bus *bus, struct sdw_msg *msg)
 266 {
 267         int ret;
 268
 269         ret = do_transfer(bus, msg);
 270         if (ret != 0 && ret != -ENODATA)
 271                 dev_err(bus->dev, "trf on Slave %d failed:%d %s addr %x count %d\n",
 272                         msg->dev_num, ret,
 273                         (msg->flags & SDW_MSG_FLAG_WRITE) ? "write" : "read",
 274                         msg->addr, msg->len);
 275
 276         if (msg->page)
 277                 sdw_reset_page(bus, msg->dev_num);
 278
 279         return ret;
 280 }
 281
 282 /**
 283  * sdw_transfer() - Synchronous transfer message to a SDW Slave device
 284  * @bus: SDW bus
 285  * @msg: SDW message to be xfered
 286  */
 287 int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 288 {
 289         int ret;
 290
 291         mutex_lock(&bus->msg_lock);
 292
 293         ret = sdw_transfer_unlocked(bus, msg);
 294
 295         mutex_unlock(&bus->msg_lock);
 296
 297         return ret;
 298 }
 299
 300 /**
 301  * sdw_transfer_defer() - Asynchronously transfer message to a SDW Slave device
 302  * @bus: SDW bus
 303  * @msg: SDW message to be xfered
 304  * @defer: Defer block for signal completion
 305  *
 306  * Caller needs to hold the msg_lock lock while calling this
 307  */
 308 int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg,
 309                        struct sdw_defer *defer)
 310 {
 311         int ret;
 312
 313         if (!bus->ops->xfer_msg_defer)
 314                 return -ENOTSUPP;
 315
 316         ret = do_transfer_defer(bus, msg, defer);
 317         if (ret != 0 && ret != -ENODATA)
 318                 dev_err(bus->dev, "Defer trf on Slave %d failed:%d\n",
 319                         msg->dev_num, ret);
 320
 321         if (msg->page)
 322                 sdw_reset_page(bus, msg->dev_num);
 323
 324         return ret;
 325 }
 326
 327 int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
 328                  u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf)
 329 {
 330         memset(msg, 0, sizeof(*msg));
 331         msg->addr = addr; /* addr is 16 bit and truncated here */
 332         msg->len = count;
 333         msg->dev_num = dev_num;
 334         msg->flags = flags;
 335         msg->buf = buf;
 336
 337         if (addr < SDW_REG_NO_PAGE) /* no paging area */
 338                 return 0;
 339
 340         if (addr >= SDW_REG_MAX) { /* illegal addr */
 341                 pr_err("SDW: Invalid address %x passed\n", addr);
 342                 return -EINVAL;
 343         }
 344
 345         if (addr < SDW_REG_OPTIONAL_PAGE) { /* 32k but no page */
 346                 if (slave && !slave->prop.paging_support)
 347                         return 0;
 348                 /* no need for else as that will fall-through to paging */
 349         }
 350
 351         /* paging mandatory */
 352         if (dev_num == SDW_ENUM_DEV_NUM || dev_num == SDW_BROADCAST_DEV_NUM) {
 353                 pr_err("SDW: Invalid device for paging :%d\n", dev_num);
 354                 return -EINVAL;
 355         }
 356
 357         if (!slave) {
 358                 pr_err("SDW: No slave for paging addr\n");
 359                 return -EINVAL;
 360         }
 361
 362         if (!slave->prop.paging_support) {
 363                 dev_err(&slave->dev,
 364                         "address %x needs paging but no support\n", addr);
 365                 return -EINVAL;
 366         }
 367
 368         msg->addr_page1 = FIELD_GET(SDW_SCP_ADDRPAGE1_MASK, addr);
 369         msg->addr_page2 = FIELD_GET(SDW_SCP_ADDRPAGE2_MASK, addr);
 370         msg->addr |= BIT(15);
 371         msg->page = true;
 372
 373         return 0;
 374 }
 375
 376 /*
 377  * Read/Write IO functions.
 378  * no_pm versions can only be called by the bus, e.g. while enumerating or
 379  * handling suspend-resume sequences.
 380  * all clients need to use the pm versions
 381  */
 382
 383 static int
 384 sdw_nread_no_pm(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 385 {
 386         struct sdw_msg msg;
 387         int ret;
 388
 389         ret = sdw_fill_msg(&msg, slave, addr, count,
 390                            slave->dev_num, SDW_MSG_FLAG_READ, val);
 391         if (ret < 0)
 392                 return ret;
 393
 394         ret = sdw_transfer(slave->bus, &msg);
 395         if (slave->is_mockup_device)
 396                 ret = 0;
 397         return ret;
 398 }
 399
 400 static int
 401 sdw_nwrite_no_pm(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 402 {
 403         struct sdw_msg msg;
 404         int ret;
 405
 406         ret = sdw_fill_msg(&msg, slave, addr, count,
 407                            slave->dev_num, SDW_MSG_FLAG_WRITE, (u8 *)val);
 408         if (ret < 0)
 409                 return ret;
 410
 411         ret = sdw_transfer(slave->bus, &msg);
 412         if (slave->is_mockup_device)
 413                 ret = 0;
 414         return ret;
 415 }
 416
 417 int sdw_write_no_pm(struct sdw_slave *slave, u32 addr, u8 value)
 418 {
 419         return sdw_nwrite_no_pm(slave, addr, 1, &value);
 420 }
 421 EXPORT_SYMBOL(sdw_write_no_pm);
 422
 423 static int
 424 sdw_bread_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr)
 425 {
 426         struct sdw_msg msg;
 427         u8 buf;
 428         int ret;
 429
 430         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 431                            SDW_MSG_FLAG_READ, &buf);
 432         if (ret < 0)
 433                 return ret;
 434
 435         ret = sdw_transfer(bus, &msg);
 436         if (ret < 0)
 437                 return ret;
 438
 439         return buf;
 440 }
 441
 442 static int
 443 sdw_bwrite_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 444 {
 445         struct sdw_msg msg;
 446         int ret;
 447
 448         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 449                            SDW_MSG_FLAG_WRITE, &value);
 450         if (ret < 0)
 451                 return ret;
 452
 453         return sdw_transfer(bus, &msg);
 454 }
 455
 456 int sdw_bread_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr)
 457 {
 458         struct sdw_msg msg;
 459         u8 buf;
 460         int ret;
 461
 462         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 463                            SDW_MSG_FLAG_READ, &buf);
 464         if (ret < 0)
 465                 return ret;
 466
 467         ret = sdw_transfer_unlocked(bus, &msg);
 468         if (ret < 0)
 469                 return ret;
 470
 471         return buf;
 472 }
 473 EXPORT_SYMBOL(sdw_bread_no_pm_unlocked);
 474
 475 int sdw_bwrite_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 476 {
 477         struct sdw_msg msg;
 478         int ret;
 479
 480         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 481                            SDW_MSG_FLAG_WRITE, &value);
 482         if (ret < 0)
 483                 return ret;
 484
 485         return sdw_transfer_unlocked(bus, &msg);
 486 }
 487 EXPORT_SYMBOL(sdw_bwrite_no_pm_unlocked);
 488
 489 int sdw_read_no_pm(struct sdw_slave *slave, u32 addr)
 490 {
 491         u8 buf;
 492         int ret;
 493
 494         ret = sdw_nread_no_pm(slave, addr, 1, &buf);
 495         if (ret < 0)
 496                 return ret;
 497         else
 498                 return buf;
 499 }
 500 EXPORT_SYMBOL(sdw_read_no_pm);
 501
 502 int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 503 {
 504         int tmp;
 505
 506         tmp = sdw_read_no_pm(slave, addr);
 507         if (tmp < 0)
 508                 return tmp;
 509
 510         tmp = (tmp & ~mask) | val;
 511         return sdw_write_no_pm(slave, addr, tmp);
 512 }
 513 EXPORT_SYMBOL(sdw_update_no_pm);
 514
 515 /* Read-Modify-Write Slave register */
 516 int sdw_update(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 517 {
 518         int tmp;
 519
 520         tmp = sdw_read(slave, addr);
 521         if (tmp < 0)
 522                 return tmp;
 523
 524         tmp = (tmp & ~mask) | val;
 525         return sdw_write(slave, addr, tmp);
 526 }
 527 EXPORT_SYMBOL(sdw_update);
 528
 529 /**
 530  * sdw_nread() - Read "n" contiguous SDW Slave registers
 531  * @slave: SDW Slave
 532  * @addr: Register address
 533  * @count: length
 534  * @val: Buffer for values to be read
 535  */
 536 int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 537 {
 538         int ret;
 539
 540         ret = pm_runtime_resume_and_get(&slave->dev);
 541         if (ret < 0 && ret != -EACCES)
 542                 return ret;
 543
 544         ret = sdw_nread_no_pm(slave, addr, count, val);
 545
 546         pm_runtime_mark_last_busy(&slave->dev);
 547         pm_runtime_put(&slave->dev);
 548
 549         return ret;
 550 }
 551 EXPORT_SYMBOL(sdw_nread);
 552
 553 /**
 554  * sdw_nwrite() - Write "n" contiguous SDW Slave registers
 555  * @slave: SDW Slave
 556  * @addr: Register address
 557  * @count: length
 558  * @val: Buffer for values to be written
 559  */
 560 int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 561 {
 562         int ret;
 563
 564         ret = pm_runtime_resume_and_get(&slave->dev);
 565         if (ret < 0 && ret != -EACCES)
 566                 return ret;
 567
 568         ret = sdw_nwrite_no_pm(slave, addr, count, val);
 569
 570         pm_runtime_mark_last_busy(&slave->dev);
 571         pm_runtime_put(&slave->dev);
 572
 573         return ret;
 574 }
 575 EXPORT_SYMBOL(sdw_nwrite);
 576
 577 /**
 578  * sdw_read() - Read a SDW Slave register
 579  * @slave: SDW Slave
 580  * @addr: Register address
 581  */
 582 int sdw_read(struct sdw_slave *slave, u32 addr)
 583 {
 584         u8 buf;
 585         int ret;
 586
 587         ret = sdw_nread(slave, addr, 1, &buf);
 588         if (ret < 0)
 589                 return ret;
 590
 591         return buf;
 592 }
 593 EXPORT_SYMBOL(sdw_read);
 594
 595 /**
 596  * sdw_write() - Write a SDW Slave register
 597  * @slave: SDW Slave
 598  * @addr: Register address
 599  * @value: Register value
 600  */
 601 int sdw_write(struct sdw_slave *slave, u32 addr, u8 value)
 602 {
 603         return sdw_nwrite(slave, addr, 1, &value);
 604 }
 605 EXPORT_SYMBOL(sdw_write);
 606
 607 /*
 608  * SDW alert handling
 609  */
 610
 611 /* called with bus_lock held */
 612 static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i)
 613 {
 614         struct sdw_slave *slave;
 615
 616         list_for_each_entry(slave, &bus->slaves, node) {
 617                 if (slave->dev_num == i)
 618                         return slave;
 619         }
 620
 621         return NULL;
 622 }
 623
 624 int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id)
 625 {
 626         if (slave->id.mfg_id != id.mfg_id ||
 627             slave->id.part_id != id.part_id ||
 628             slave->id.class_id != id.class_id ||
 629             (slave->id.unique_id != SDW_IGNORED_UNIQUE_ID &&
 630              slave->id.unique_id != id.unique_id))
 631                 return -ENODEV;
 632
 633         return 0;
 634 }
 635 EXPORT_SYMBOL(sdw_compare_devid);
 636
 637 /* called with bus_lock held */
 638 static int sdw_get_device_num(struct sdw_slave *slave)
 639 {
 640         int bit;
 641
 642         bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES);
 643         if (bit == SDW_MAX_DEVICES) {
 644                 bit = -ENODEV;
 645                 goto err;
 646         }
 647
 648         /*
 649          * Do not update dev_num in Slave data structure here,
 650          * Update once program dev_num is successful
 651          */
 652         set_bit(bit, slave->bus->assigned);
 653
 654 err:
 655         return bit;
 656 }
 657
 658 static int sdw_assign_device_num(struct sdw_slave *slave)
 659 {
 660         struct sdw_bus *bus = slave->bus;
 661         int ret, dev_num;
 662         bool new_device = false;
 663
 664         /* check first if device number is assigned, if so reuse that */
 665         if (!slave->dev_num) {
 666                 if (!slave->dev_num_sticky) {
 667                         mutex_lock(&slave->bus->bus_lock);
 668                         dev_num = sdw_get_device_num(slave);
 669                         mutex_unlock(&slave->bus->bus_lock);
 670                         if (dev_num < 0) {
 671                                 dev_err(bus->dev, "Get dev_num failed: %d\n",
 672                                         dev_num);
 673                                 return dev_num;
 674                         }
 675                         slave->dev_num = dev_num;
 676                         slave->dev_num_sticky = dev_num;
 677                         new_device = true;
 678                 } else {
 679                         slave->dev_num = slave->dev_num_sticky;
 680                 }
 681         }
 682
 683         if (!new_device)
 684                 dev_dbg(bus->dev,
 685                         "Slave already registered, reusing dev_num:%d\n",
 686                         slave->dev_num);
 687
 688         /* Clear the slave->dev_num to transfer message on device 0 */
 689         dev_num = slave->dev_num;
 690         slave->dev_num = 0;
 691
 692         ret = sdw_write_no_pm(slave, SDW_SCP_DEVNUMBER, dev_num);
 693         if (ret < 0) {
 694                 dev_err(bus->dev, "Program device_num %d failed: %d\n",
 695                         dev_num, ret);
 696                 return ret;
 697         }
 698
 699         /* After xfer of msg, restore dev_num */
 700         slave->dev_num = slave->dev_num_sticky;
 701
 702         return 0;
 703 }
 704
 705 void sdw_extract_slave_id(struct sdw_bus *bus,
 706                           u64 addr, struct sdw_slave_id *id)
 707 {
 708         dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr);
 709
 710         id->sdw_version = SDW_VERSION(addr);
 711         id->unique_id = SDW_UNIQUE_ID(addr);
 712         id->mfg_id = SDW_MFG_ID(addr);
 713         id->part_id = SDW_PART_ID(addr);
 714         id->class_id = SDW_CLASS_ID(addr);
 715
 716         dev_dbg(bus->dev,
 717                 "SDW Slave class_id 0x%02x, mfg_id 0x%04x, part_id 0x%04x, unique_id 0x%x, version 0x%x\n",
 718                 id->class_id, id->mfg_id, id->part_id, id->unique_id, id->sdw_version);
 719 }
 720 EXPORT_SYMBOL(sdw_extract_slave_id);
 721
 722 static int sdw_program_device_num(struct sdw_bus *bus)
 723 {
 724         u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0};
 725         struct sdw_slave *slave, *_s;
 726         struct sdw_slave_id id;
 727         struct sdw_msg msg;
 728         bool found;
 729         int count = 0, ret;
 730         u64 addr;
 731
 732         /* No Slave, so use raw xfer api */
 733         ret = sdw_fill_msg(&msg, NULL, SDW_SCP_DEVID_0,
 734                            SDW_NUM_DEV_ID_REGISTERS, 0, SDW_MSG_FLAG_READ, buf);
 735         if (ret < 0)
 736                 return ret;
 737
 738         do {
 739                 ret = sdw_transfer(bus, &msg);
 740                 if (ret == -ENODATA) { /* end of device id reads */
 741                         dev_dbg(bus->dev, "No more devices to enumerate\n");
 742                         ret = 0;
 743                         break;
 744                 }
 745                 if (ret < 0) {
 746                         dev_err(bus->dev, "DEVID read fail:%d\n", ret);
 747                         break;
 748                 }
 749
 750                 /*
 751                  * Construct the addr and extract. Cast the higher shift
 752                  * bits to avoid truncation due to size limit.
 753                  */
 754                 addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) |
 755                         ((u64)buf[2] << 24) | ((u64)buf[1] << 32) |
 756                         ((u64)buf[0] << 40);
 757
 758                 sdw_extract_slave_id(bus, addr, &id);
 759
 760                 found = false;
 761                 /* Now compare with entries */
 762                 list_for_each_entry_safe(slave, _s, &bus->slaves, node) {
 763                         if (sdw_compare_devid(slave, id) == 0) {
 764                                 found = true;
 765
 766                                 /*
 767                                  * Assign a new dev_num to this Slave and
 768                                  * not mark it present. It will be marked
 769                                  * present after it reports ATTACHED on new
 770                                  * dev_num
 771                                  */
 772                                 ret = sdw_assign_device_num(slave);
 773                                 if (ret < 0) {
 774                                         dev_err(bus->dev,
 775                                                 "Assign dev_num failed:%d\n",
 776                                                 ret);
 777                                         return ret;
 778                                 }
 779
 780                                 break;
 781                         }
 782                 }
 783
 784                 if (!found) {
 785                         /* TODO: Park this device in Group 13 */
 786
 787                         /*
 788                          * add Slave device even if there is no platform
 789                          * firmware description. There will be no driver probe
 790                          * but the user/integration will be able to see the
 791                          * device, enumeration status and device number in sysfs
 792                          */
 793                         sdw_slave_add(bus, &id, NULL);
 794
 795                         dev_err(bus->dev, "Slave Entry not found\n");
 796                 }
 797
 798                 count++;
 799
 800                 /*
 801                  * Check till error out or retry (count) exhausts.
 802                  * Device can drop off and rejoin during enumeration
 803                  * so count till twice the bound.
 804                  */
 805
 806         } while (ret == 0 && count < (SDW_MAX_DEVICES * 2));
 807
 808         return ret;
 809 }
 810
 811 static void sdw_modify_slave_status(struct sdw_slave *slave,
 812                                     enum sdw_slave_status status)
 813 {
 814         struct sdw_bus *bus = slave->bus;
 815
 816         mutex_lock(&bus->bus_lock);
 817
 818         dev_vdbg(bus->dev,
 819                  "%s: changing status slave %d status %d new status %d\n",
 820                  __func__, slave->dev_num, slave->status, status);
 821
 822         if (status == SDW_SLAVE_UNATTACHED) {
 823                 dev_dbg(&slave->dev,
 824                         "%s: initializing enumeration and init completion for Slave %d\n",
 825                         __func__, slave->dev_num);
 826
 827                 init_completion(&slave->enumeration_complete);
 828                 init_completion(&slave->initialization_complete);
 829
 830         } else if ((status == SDW_SLAVE_ATTACHED) &&
 831                    (slave->status == SDW_SLAVE_UNATTACHED)) {
 832                 dev_dbg(&slave->dev,
 833                         "%s: signaling enumeration completion for Slave %d\n",
 834                         __func__, slave->dev_num);
 835
 836                 complete(&slave->enumeration_complete);
 837         }
 838         slave->status = status;
 839         mutex_unlock(&bus->bus_lock);
 840 }
 841
 842 static int sdw_slave_clk_stop_callback(struct sdw_slave *slave,
 843                                        enum sdw_clk_stop_mode mode,
 844                                        enum sdw_clk_stop_type type)
 845 {
 846         int ret = 0;
 847
 848         mutex_lock(&slave->sdw_dev_lock);
 849
 850         if (slave->probed)  {
 851                 struct device *dev = &slave->dev;
 852                 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
 853
 854                 if (drv->ops && drv->ops->clk_stop)
 855                         ret = drv->ops->clk_stop(slave, mode, type);
 856         }
 857
 858         mutex_unlock(&slave->sdw_dev_lock);
 859
 860         return ret;
 861 }
 862
 863 static int sdw_slave_clk_stop_prepare(struct sdw_slave *slave,
 864                                       enum sdw_clk_stop_mode mode,
 865                                       bool prepare)
 866 {
 867         bool wake_en;
 868         u32 val = 0;
 869         int ret;
 870
 871         wake_en = slave->prop.wake_capable;
 872
 873         if (prepare) {
 874                 val = SDW_SCP_SYSTEMCTRL_CLK_STP_PREP;
 875
 876                 if (mode == SDW_CLK_STOP_MODE1)
 877                         val |= SDW_SCP_SYSTEMCTRL_CLK_STP_MODE1;
 878
 879                 if (wake_en)
 880                         val |= SDW_SCP_SYSTEMCTRL_WAKE_UP_EN;
 881         } else {
 882                 ret = sdw_read_no_pm(slave, SDW_SCP_SYSTEMCTRL);
 883                 if (ret < 0) {
 884                         if (ret != -ENODATA)
 885                                 dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL read failed:%d\n", ret);
 886                         return ret;
 887                 }
 888                 val = ret;
 889                 val &= ~(SDW_SCP_SYSTEMCTRL_CLK_STP_PREP);
 890         }
 891
 892         ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val);
 893
 894         if (ret < 0 && ret != -ENODATA)
 895                 dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL write failed:%d\n", ret);
 896
 897         return ret;
 898 }
 899
 900 static int sdw_bus_wait_for_clk_prep_deprep(struct sdw_bus *bus, u16 dev_num)
 901 {
 902         int retry = bus->clk_stop_timeout;
 903         int val;
 904
 905         do {
 906                 val = sdw_bread_no_pm(bus, dev_num, SDW_SCP_STAT);
 907                 if (val < 0) {
 908                         if (val != -ENODATA)
 909                                 dev_err(bus->dev, "SDW_SCP_STAT bread failed:%d\n", val);
 910                         return val;
 911                 }
 912                 val &= SDW_SCP_STAT_CLK_STP_NF;
 913                 if (!val) {
 914                         dev_dbg(bus->dev, "clock stop prep/de-prep done slave:%d\n",
 915                                 dev_num);
 916                         return 0;
 917                 }
 918
 919                 usleep_range(1000, 1500);
 920                 retry--;
 921         } while (retry);
 922
 923         dev_err(bus->dev, "clock stop prep/de-prep failed slave:%d\n",
 924                 dev_num);
 925
 926         return -ETIMEDOUT;
 927 }
 928
 929 /**
 930  * sdw_bus_prep_clk_stop: prepare Slave(s) for clock stop
 931  *
 932  * @bus: SDW bus instance
 933  *
 934  * Query Slave for clock stop mode and prepare for that mode.
 935  */
 936 int sdw_bus_prep_clk_stop(struct sdw_bus *bus)
 937 {
 938         bool simple_clk_stop = true;
 939         struct sdw_slave *slave;
 940         bool is_slave = false;
 941         int ret = 0;
 942
 943         /*
 944          * In order to save on transition time, prepare
 945          * each Slave and then wait for all Slave(s) to be
 946          * prepared for clock stop.
 947          * If one of the Slave devices has lost sync and
 948          * replies with Command Ignored/-ENODATA, we continue
 949          * the loop
 950          */
 951         list_for_each_entry(slave, &bus->slaves, node) {
 952                 if (!slave->dev_num)
 953                         continue;
 954
 955                 if (slave->status != SDW_SLAVE_ATTACHED &&
 956                     slave->status != SDW_SLAVE_ALERT)
 957                         continue;
 958
 959                 /* Identify if Slave(s) are available on Bus */
 960                 is_slave = true;
 961
 962                 ret = sdw_slave_clk_stop_callback(slave,
 963                                                   SDW_CLK_STOP_MODE0,
 964                                                   SDW_CLK_PRE_PREPARE);
 965                 if (ret < 0 && ret != -ENODATA) {
 966                         dev_err(&slave->dev, "clock stop pre-prepare cb failed:%d\n", ret);
 967                         return ret;
 968                 }
 969
 970                 /* Only prepare a Slave device if needed */
 971                 if (!slave->prop.simple_clk_stop_capable) {
 972                         simple_clk_stop = false;
 973
 974                         ret = sdw_slave_clk_stop_prepare(slave,
 975                                                          SDW_CLK_STOP_MODE0,
 976                                                          true);
 977                         if (ret < 0 && ret != -ENODATA) {
 978                                 dev_err(&slave->dev, "clock stop prepare failed:%d\n", ret);
 979                                 return ret;
 980                         }
 981                 }
 982         }
 983
 984         /* Skip remaining clock stop preparation if no Slave is attached */
 985         if (!is_slave)
 986                 return 0;
 987
 988         /*
 989          * Don't wait for all Slaves to be ready if they follow the simple
 990          * state machine
 991          */
 992         if (!simple_clk_stop) {
 993                 ret = sdw_bus_wait_for_clk_prep_deprep(bus,
 994                                                        SDW_BROADCAST_DEV_NUM);
 995                 /*
 996                  * if there are no Slave devices present and the reply is
 997                  * Command_Ignored/-ENODATA, we don't need to continue with the
 998                  * flow and can just return here. The error code is not modified
 999                  * and its handling left as an exercise for the caller.
1000                  */
1001                 if (ret < 0)
1002                         return ret;
1003         }
1004
1005         /* Inform slaves that prep is done */
1006         list_for_each_entry(slave, &bus->slaves, node) {
1007                 if (!slave->dev_num)
1008                         continue;
1009
1010                 if (slave->status != SDW_SLAVE_ATTACHED &&
1011                     slave->status != SDW_SLAVE_ALERT)
1012                         continue;
1013
1014                 ret = sdw_slave_clk_stop_callback(slave,
1015                                                   SDW_CLK_STOP_MODE0,
1016                                                   SDW_CLK_POST_PREPARE);
1017
1018                 if (ret < 0 && ret != -ENODATA) {
1019                         dev_err(&slave->dev, "clock stop post-prepare cb failed:%d\n", ret);
1020                         return ret;
1021                 }
1022         }
1023
1024         return 0;
1025 }
1026 EXPORT_SYMBOL(sdw_bus_prep_clk_stop);
1027
1028 /**
1029  * sdw_bus_clk_stop: stop bus clock
1030  *
1031  * @bus: SDW bus instance
1032  *
1033  * After preparing the Slaves for clock stop, stop the clock by broadcasting
1034  * write to SCP_CTRL register.
1035  */
1036 int sdw_bus_clk_stop(struct sdw_bus *bus)
1037 {
1038         int ret;
1039
1040         /*
1041          * broadcast clock stop now, attached Slaves will ACK this,
1042          * unattached will ignore
1043          */
1044         ret = sdw_bwrite_no_pm(bus, SDW_BROADCAST_DEV_NUM,
1045                                SDW_SCP_CTRL, SDW_SCP_CTRL_CLK_STP_NOW);
1046         if (ret < 0) {
1047                 if (ret != -ENODATA)
1048                         dev_err(bus->dev, "ClockStopNow Broadcast msg failed %d\n", ret);
1049                 return ret;
1050         }
1051
1052         return 0;
1053 }
1054 EXPORT_SYMBOL(sdw_bus_clk_stop);
1055
1056 /**
1057  * sdw_bus_exit_clk_stop: Exit clock stop mode
1058  *
1059  * @bus: SDW bus instance
1060  *
1061  * This De-prepares the Slaves by exiting Clock Stop Mode 0. For the Slaves
1062  * exiting Clock Stop Mode 1, they will be de-prepared after they enumerate
1063  * back.
1064  */
1065 int sdw_bus_exit_clk_stop(struct sdw_bus *bus)
1066 {
1067         bool simple_clk_stop = true;
1068         struct sdw_slave *slave;
1069         bool is_slave = false;
1070         int ret;
1071
1072         /*
1073          * In order to save on transition time, de-prepare
1074          * each Slave and then wait for all Slave(s) to be
1075          * de-prepared after clock resume.
1076          */
1077         list_for_each_entry(slave, &bus->slaves, node) {
1078                 if (!slave->dev_num)
1079                         continue;
1080
1081                 if (slave->status != SDW_SLAVE_ATTACHED &&
1082                     slave->status != SDW_SLAVE_ALERT)
1083                         continue;
1084
1085                 /* Identify if Slave(s) are available on Bus */
1086                 is_slave = true;
1087
1088                 ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1089                                                   SDW_CLK_PRE_DEPREPARE);
1090                 if (ret < 0)
1091                         dev_warn(&slave->dev, "clock stop pre-deprepare cb failed:%d\n", ret);
1092
1093                 /* Only de-prepare a Slave device if needed */
1094                 if (!slave->prop.simple_clk_stop_capable) {
1095                         simple_clk_stop = false;
1096
1097                         ret = sdw_slave_clk_stop_prepare(slave, SDW_CLK_STOP_MODE0,
1098                                                          false);
1099
1100                         if (ret < 0)
1101                                 dev_warn(&slave->dev, "clock stop deprepare failed:%d\n", ret);
1102                 }
1103         }
1104
1105         /* Skip remaining clock stop de-preparation if no Slave is attached */
1106         if (!is_slave)
1107                 return 0;
1108
1109         /*
1110          * Don't wait for all Slaves to be ready if they follow the simple
1111          * state machine
1112          */
1113         if (!simple_clk_stop) {
1114                 ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM);
1115                 if (ret < 0)
1116                         dev_warn(bus->dev, "clock stop deprepare wait failed:%d\n", ret);
1117         }
1118
1119         list_for_each_entry(slave, &bus->slaves, node) {
1120                 if (!slave->dev_num)
1121                         continue;
1122
1123                 if (slave->status != SDW_SLAVE_ATTACHED &&
1124                     slave->status != SDW_SLAVE_ALERT)
1125                         continue;
1126
1127                 ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1128                                                   SDW_CLK_POST_DEPREPARE);
1129                 if (ret < 0)
1130                         dev_warn(&slave->dev, "clock stop post-deprepare cb failed:%d\n", ret);
1131         }
1132
1133         return 0;
1134 }
1135 EXPORT_SYMBOL(sdw_bus_exit_clk_stop);
1136
1137 int sdw_configure_dpn_intr(struct sdw_slave *slave,
1138                            int port, bool enable, int mask)
1139 {
1140         u32 addr;
1141         int ret;
1142         u8 val = 0;
1143
1144         if (slave->bus->params.s_data_mode != SDW_PORT_DATA_MODE_NORMAL) {
1145                 dev_dbg(&slave->dev, "TEST FAIL interrupt %s\n",
1146                         enable ? "on" : "off");
1147                 mask |= SDW_DPN_INT_TEST_FAIL;
1148         }
1149
1150         addr = SDW_DPN_INTMASK(port);
1151
1152         /* Set/Clear port ready interrupt mask */
1153         if (enable) {
1154                 val |= mask;
1155                 val |= SDW_DPN_INT_PORT_READY;
1156         } else {
1157                 val &= ~(mask);
1158                 val &= ~SDW_DPN_INT_PORT_READY;
1159         }
1160
1161         ret = sdw_update(slave, addr, (mask | SDW_DPN_INT_PORT_READY), val);
1162         if (ret < 0)
1163                 dev_err(&slave->dev,
1164                         "SDW_DPN_INTMASK write failed:%d\n", val);
1165
1166         return ret;
1167 }
1168
1169 static int sdw_slave_set_frequency(struct sdw_slave *slave)
1170 {
1171         u32 mclk_freq = slave->bus->prop.mclk_freq;
1172         u32 curr_freq = slave->bus->params.curr_dr_freq >> 1;
1173         unsigned int scale;
1174         u8 scale_index;
1175         u8 base;
1176         int ret;
1177
1178         /*
1179          * frequency base and scale registers are required for SDCA
1180          * devices. They may also be used for 1.2+/non-SDCA devices,
1181          * but we will need a DisCo property to cover this case
1182          */
1183         if (!slave->id.class_id)
1184                 return 0;
1185
1186         if (!mclk_freq) {
1187                 dev_err(&slave->dev,
1188                         "no bus MCLK, cannot set SDW_SCP_BUS_CLOCK_BASE\n");
1189                 return -EINVAL;
1190         }
1191
1192         /*
1193          * map base frequency using Table 89 of SoundWire 1.2 spec.
1194          * The order of the tests just follows the specification, this
1195          * is not a selection between possible values or a search for
1196          * the best value but just a mapping.  Only one case per platform
1197          * is relevant.
1198          * Some BIOS have inconsistent values for mclk_freq but a
1199          * correct root so we force the mclk_freq to avoid variations.
1200          */
1201         if (!(19200000 % mclk_freq)) {
1202                 mclk_freq = 19200000;
1203                 base = SDW_SCP_BASE_CLOCK_19200000_HZ;
1204         } else if (!(24000000 % mclk_freq)) {
1205                 mclk_freq = 24000000;
1206                 base = SDW_SCP_BASE_CLOCK_24000000_HZ;
1207         } else if (!(24576000 % mclk_freq)) {
1208                 mclk_freq = 24576000;
1209                 base = SDW_SCP_BASE_CLOCK_24576000_HZ;
1210         } else if (!(22579200 % mclk_freq)) {
1211                 mclk_freq = 22579200;
1212                 base = SDW_SCP_BASE_CLOCK_22579200_HZ;
1213         } else if (!(32000000 % mclk_freq)) {
1214                 mclk_freq = 32000000;
1215                 base = SDW_SCP_BASE_CLOCK_32000000_HZ;
1216         } else {
1217                 dev_err(&slave->dev,
1218                         "Unsupported clock base, mclk %d\n",
1219                         mclk_freq);
1220                 return -EINVAL;
1221         }
1222
1223         if (mclk_freq % curr_freq) {
1224                 dev_err(&slave->dev,
1225                         "mclk %d is not multiple of bus curr_freq %d\n",
1226                         mclk_freq, curr_freq);
1227                 return -EINVAL;
1228         }
1229
1230         scale = mclk_freq / curr_freq;
1231
1232         /*
1233          * map scale to Table 90 of SoundWire 1.2 spec - and check
1234          * that the scale is a power of two and maximum 64
1235          */
1236         scale_index = ilog2(scale);
1237
1238         if (BIT(scale_index) != scale || scale_index > 6) {
1239                 dev_err(&slave->dev,
1240                         "No match found for scale %d, bus mclk %d curr_freq %d\n",
1241                         scale, mclk_freq, curr_freq);
1242                 return -EINVAL;
1243         }
1244         scale_index++;
1245
1246         ret = sdw_write_no_pm(slave, SDW_SCP_BUS_CLOCK_BASE, base);
1247         if (ret < 0) {
1248                 dev_err(&slave->dev,
1249                         "SDW_SCP_BUS_CLOCK_BASE write failed:%d\n", ret);
1250                 return ret;
1251         }
1252
1253         /* initialize scale for both banks */
1254         ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B0, scale_index);
1255         if (ret < 0) {
1256                 dev_err(&slave->dev,
1257                         "SDW_SCP_BUSCLOCK_SCALE_B0 write failed:%d\n", ret);
1258                 return ret;
1259         }
1260         ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B1, scale_index);
1261         if (ret < 0)
1262                 dev_err(&slave->dev,
1263                         "SDW_SCP_BUSCLOCK_SCALE_B1 write failed:%d\n", ret);
1264
1265         dev_dbg(&slave->dev,
1266                 "Configured bus base %d, scale %d, mclk %d, curr_freq %d\n",
1267                 base, scale_index, mclk_freq, curr_freq);
1268
1269         return ret;
1270 }
1271
1272 static int sdw_initialize_slave(struct sdw_slave *slave)
1273 {
1274         struct sdw_slave_prop *prop = &slave->prop;
1275         int status;
1276         int ret;
1277         u8 val;
1278
1279         ret = sdw_slave_set_frequency(slave);
1280         if (ret < 0)
1281                 return ret;
1282
1283         if (slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH) {
1284                 /* Clear bus clash interrupt before enabling interrupt mask */
1285                 status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1286                 if (status < 0) {
1287                         dev_err(&slave->dev,
1288                                 "SDW_SCP_INT1 (BUS_CLASH) read failed:%d\n", status);
1289                         return status;
1290                 }
1291                 if (status & SDW_SCP_INT1_BUS_CLASH) {
1292                         dev_warn(&slave->dev, "Bus clash detected before INT mask is enabled\n");
1293                         ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_BUS_CLASH);
1294                         if (ret < 0) {
1295                                 dev_err(&slave->dev,
1296                                         "SDW_SCP_INT1 (BUS_CLASH) write failed:%d\n", ret);
1297                                 return ret;
1298                         }
1299                 }
1300         }
1301         if ((slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY) &&
1302             !(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY)) {
1303                 /* Clear parity interrupt before enabling interrupt mask */
1304                 status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1305                 if (status < 0) {
1306                         dev_err(&slave->dev,
1307                                 "SDW_SCP_INT1 (PARITY) read failed:%d\n", status);
1308                         return status;
1309                 }
1310                 if (status & SDW_SCP_INT1_PARITY) {
1311                         dev_warn(&slave->dev, "PARITY error detected before INT mask is enabled\n");
1312                         ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_PARITY);
1313                         if (ret < 0) {
1314                                 dev_err(&slave->dev,
1315                                         "SDW_SCP_INT1 (PARITY) write failed:%d\n", ret);
1316                                 return ret;
1317                         }
1318                 }
1319         }
1320
1321         /*
1322          * Set SCP_INT1_MASK register, typically bus clash and
1323          * implementation-defined interrupt mask. The Parity detection
1324          * may not always be correct on startup so its use is
1325          * device-dependent, it might e.g. only be enabled in
1326          * steady-state after a couple of frames.
1327          */
1328         val = slave->prop.scp_int1_mask;
1329
1330         /* Enable SCP interrupts */
1331         ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val);
1332         if (ret < 0) {
1333                 dev_err(&slave->dev,
1334                         "SDW_SCP_INTMASK1 write failed:%d\n", ret);
1335                 return ret;
1336         }
1337
1338         /* No need to continue if DP0 is not present */
1339         if (!slave->prop.dp0_prop)
1340                 return 0;
1341
1342         /* Enable DP0 interrupts */
1343         val = prop->dp0_prop->imp_def_interrupts;
1344         val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE;
1345
1346         ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val);
1347         if (ret < 0)
1348                 dev_err(&slave->dev,
1349                         "SDW_DP0_INTMASK read failed:%d\n", ret);
1350         return ret;
1351 }
1352
1353 static int sdw_handle_dp0_interrupt(struct sdw_slave *slave, u8 *slave_status)
1354 {
1355         u8 clear, impl_int_mask;
1356         int status, status2, ret, count = 0;
1357
1358         status = sdw_read_no_pm(slave, SDW_DP0_INT);
1359         if (status < 0) {
1360                 dev_err(&slave->dev,
1361                         "SDW_DP0_INT read failed:%d\n", status);
1362                 return status;
1363         }
1364
1365         do {
1366                 clear = status & ~SDW_DP0_INTERRUPTS;
1367
1368                 if (status & SDW_DP0_INT_TEST_FAIL) {
1369                         dev_err(&slave->dev, "Test fail for port 0\n");
1370                         clear |= SDW_DP0_INT_TEST_FAIL;
1371                 }
1372
1373                 /*
1374                  * Assumption: PORT_READY interrupt will be received only for
1375                  * ports implementing Channel Prepare state machine (CP_SM)
1376                  */
1377
1378                 if (status & SDW_DP0_INT_PORT_READY) {
1379                         complete(&slave->port_ready[0]);
1380                         clear |= SDW_DP0_INT_PORT_READY;
1381                 }
1382
1383                 if (status & SDW_DP0_INT_BRA_FAILURE) {
1384                         dev_err(&slave->dev, "BRA failed\n");
1385                         clear |= SDW_DP0_INT_BRA_FAILURE;
1386                 }
1387
1388                 impl_int_mask = SDW_DP0_INT_IMPDEF1 |
1389                         SDW_DP0_INT_IMPDEF2 | SDW_DP0_INT_IMPDEF3;
1390
1391                 if (status & impl_int_mask) {
1392                         clear |= impl_int_mask;
1393                         *slave_status = clear;
1394                 }
1395
1396                 /* clear the interrupts but don't touch reserved and SDCA_CASCADE fields */
1397                 ret = sdw_write_no_pm(slave, SDW_DP0_INT, clear);
1398                 if (ret < 0) {
1399                         dev_err(&slave->dev,
1400                                 "SDW_DP0_INT write failed:%d\n", ret);
1401                         return ret;
1402                 }
1403
1404                 /* Read DP0 interrupt again */
1405                 status2 = sdw_read_no_pm(slave, SDW_DP0_INT);
1406                 if (status2 < 0) {
1407                         dev_err(&slave->dev,
1408                                 "SDW_DP0_INT read failed:%d\n", status2);
1409                         return status2;
1410                 }
1411                 /* filter to limit loop to interrupts identified in the first status read */
1412                 status &= status2;
1413
1414                 count++;
1415
1416                 /* we can get alerts while processing so keep retrying */
1417         } while ((status & SDW_DP0_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1418
1419         if (count == SDW_READ_INTR_CLEAR_RETRY)
1420                 dev_warn(&slave->dev, "Reached MAX_RETRY on DP0 read\n");
1421
1422         return ret;
1423 }
1424
1425 static int sdw_handle_port_interrupt(struct sdw_slave *slave,
1426                                      int port, u8 *slave_status)
1427 {
1428         u8 clear, impl_int_mask;
1429         int status, status2, ret, count = 0;
1430         u32 addr;
1431
1432         if (port == 0)
1433                 return sdw_handle_dp0_interrupt(slave, slave_status);
1434
1435         addr = SDW_DPN_INT(port);
1436         status = sdw_read_no_pm(slave, addr);
1437         if (status < 0) {
1438                 dev_err(&slave->dev,
1439                         "SDW_DPN_INT read failed:%d\n", status);
1440
1441                 return status;
1442         }
1443
1444         do {
1445                 clear = status & ~SDW_DPN_INTERRUPTS;
1446
1447                 if (status & SDW_DPN_INT_TEST_FAIL) {
1448                         dev_err(&slave->dev, "Test fail for port:%d\n", port);
1449                         clear |= SDW_DPN_INT_TEST_FAIL;
1450                 }
1451
1452                 /*
1453                  * Assumption: PORT_READY interrupt will be received only
1454                  * for ports implementing CP_SM.
1455                  */
1456                 if (status & SDW_DPN_INT_PORT_READY) {
1457                         complete(&slave->port_ready[port]);
1458                         clear |= SDW_DPN_INT_PORT_READY;
1459                 }
1460
1461                 impl_int_mask = SDW_DPN_INT_IMPDEF1 |
1462                         SDW_DPN_INT_IMPDEF2 | SDW_DPN_INT_IMPDEF3;
1463
1464                 if (status & impl_int_mask) {
1465                         clear |= impl_int_mask;
1466                         *slave_status = clear;
1467                 }
1468
1469                 /* clear the interrupt but don't touch reserved fields */
1470                 ret = sdw_write_no_pm(slave, addr, clear);
1471                 if (ret < 0) {
1472                         dev_err(&slave->dev,
1473                                 "SDW_DPN_INT write failed:%d\n", ret);
1474                         return ret;
1475                 }
1476
1477                 /* Read DPN interrupt again */
1478                 status2 = sdw_read_no_pm(slave, addr);
1479                 if (status2 < 0) {
1480                         dev_err(&slave->dev,
1481                                 "SDW_DPN_INT read failed:%d\n", status2);
1482                         return status2;
1483                 }
1484                 /* filter to limit loop to interrupts identified in the first status read */
1485                 status &= status2;
1486
1487                 count++;
1488
1489                 /* we can get alerts while processing so keep retrying */
1490         } while ((status & SDW_DPN_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1491
1492         if (count == SDW_READ_INTR_CLEAR_RETRY)
1493                 dev_warn(&slave->dev, "Reached MAX_RETRY on port read");
1494
1495         return ret;
1496 }
1497
1498 static int sdw_handle_slave_alerts(struct sdw_slave *slave)
1499 {
1500         struct sdw_slave_intr_status slave_intr;
1501         u8 clear = 0, bit, port_status[15] = {0};
1502         int port_num, stat, ret, count = 0;
1503         unsigned long port;
1504         bool slave_notify;
1505         u8 sdca_cascade = 0;
1506         u8 buf, buf2[2], _buf, _buf2[2];
1507         bool parity_check;
1508         bool parity_quirk;
1509
1510         sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);
1511
1512         ret = pm_runtime_resume_and_get(&slave->dev);
1513         if (ret < 0 && ret != -EACCES) {
1514                 dev_err(&slave->dev, "Failed to resume device: %d\n", ret);
1515                 return ret;
1516         }
1517
1518         /* Read Intstat 1, Intstat 2 and Intstat 3 registers */
1519         ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1520         if (ret < 0) {
1521                 dev_err(&slave->dev,
1522                         "SDW_SCP_INT1 read failed:%d\n", ret);
1523                 goto io_err;
1524         }
1525         buf = ret;
1526
1527         ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2);
1528         if (ret < 0) {
1529                 dev_err(&slave->dev,
1530                         "SDW_SCP_INT2/3 read failed:%d\n", ret);
1531                 goto io_err;
1532         }
1533
1534         if (slave->prop.is_sdca) {
1535                 ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1536                 if (ret < 0) {
1537                         dev_err(&slave->dev,
1538                                 "SDW_DP0_INT read failed:%d\n", ret);
1539                         goto io_err;
1540                 }
1541                 sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1542         }
1543
1544         do {
1545                 slave_notify = false;
1546
1547                 /*
1548                  * Check parity, bus clash and Slave (impl defined)
1549                  * interrupt
1550                  */
1551                 if (buf & SDW_SCP_INT1_PARITY) {
1552                         parity_check = slave->prop.scp_int1_mask & SDW_SCP_INT1_PARITY;
1553                         parity_quirk = !slave->first_interrupt_done &&
1554                                 (slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY);
1555
1556                         if (parity_check && !parity_quirk)
1557                                 dev_err(&slave->dev, "Parity error detected\n");
1558                         clear |= SDW_SCP_INT1_PARITY;
1559                 }
1560
1561                 if (buf & SDW_SCP_INT1_BUS_CLASH) {
1562                         if (slave->prop.scp_int1_mask & SDW_SCP_INT1_BUS_CLASH)
1563                                 dev_err(&slave->dev, "Bus clash detected\n");
1564                         clear |= SDW_SCP_INT1_BUS_CLASH;
1565                 }
1566
1567                 /*
1568                  * When bus clash or parity errors are detected, such errors
1569                  * are unlikely to be recoverable errors.
1570                  * TODO: In such scenario, reset bus. Make this configurable
1571                  * via sysfs property with bus reset being the default.
1572                  */
1573
1574                 if (buf & SDW_SCP_INT1_IMPL_DEF) {
1575                         if (slave->prop.scp_int1_mask & SDW_SCP_INT1_IMPL_DEF) {
1576                                 dev_dbg(&slave->dev, "Slave impl defined interrupt\n");
1577                                 slave_notify = true;
1578                         }
1579                         clear |= SDW_SCP_INT1_IMPL_DEF;
1580                 }
1581
1582                 /* the SDCA interrupts are cleared in the codec driver .interrupt_callback() */
1583                 if (sdca_cascade)
1584                         slave_notify = true;
1585
1586                 /* Check port 0 - 3 interrupts */
1587                 port = buf & SDW_SCP_INT1_PORT0_3;
1588
1589                 /* To get port number corresponding to bits, shift it */
1590                 port = FIELD_GET(SDW_SCP_INT1_PORT0_3, port);
1591                 for_each_set_bit(bit, &port, 8) {
1592                         sdw_handle_port_interrupt(slave, bit,
1593                                                   &port_status[bit]);
1594                 }
1595
1596                 /* Check if cascade 2 interrupt is present */
1597                 if (buf & SDW_SCP_INT1_SCP2_CASCADE) {
1598                         port = buf2[0] & SDW_SCP_INTSTAT2_PORT4_10;
1599                         for_each_set_bit(bit, &port, 8) {
1600                                 /* scp2 ports start from 4 */
1601                                 port_num = bit + 3;
1602                                 sdw_handle_port_interrupt(slave,
1603                                                 port_num,
1604                                                 &port_status[port_num]);
1605                         }
1606                 }
1607
1608                 /* now check last cascade */
1609                 if (buf2[0] & SDW_SCP_INTSTAT2_SCP3_CASCADE) {
1610                         port = buf2[1] & SDW_SCP_INTSTAT3_PORT11_14;
1611                         for_each_set_bit(bit, &port, 8) {
1612                                 /* scp3 ports start from 11 */
1613                                 port_num = bit + 10;
1614                                 sdw_handle_port_interrupt(slave,
1615                                                 port_num,
1616                                                 &port_status[port_num]);
1617                         }
1618                 }
1619
1620                 /* Update the Slave driver */
1621                 if (slave_notify) {
1622                         mutex_lock(&slave->sdw_dev_lock);
1623
1624                         if (slave->probed) {
1625                                 struct device *dev = &slave->dev;
1626                                 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
1627
1628                                 if (drv->ops && drv->ops->interrupt_callback) {
1629                                         slave_intr.sdca_cascade = sdca_cascade;
1630                                         slave_intr.control_port = clear;
1631                                         memcpy(slave_intr.port, &port_status,
1632                                                sizeof(slave_intr.port));
1633
1634                                         drv->ops->interrupt_callback(slave, &slave_intr);
1635                                 }
1636                         }
1637
1638                         mutex_unlock(&slave->sdw_dev_lock);
1639                 }
1640
1641                 /* Ack interrupt */
1642                 ret = sdw_write_no_pm(slave, SDW_SCP_INT1, clear);
1643                 if (ret < 0) {
1644                         dev_err(&slave->dev,
1645                                 "SDW_SCP_INT1 write failed:%d\n", ret);
1646                         goto io_err;
1647                 }
1648
1649                 /* at this point all initial interrupt sources were handled */
1650                 slave->first_interrupt_done = true;
1651
1652                 /*
1653                  * Read status again to ensure no new interrupts arrived
1654                  * while servicing interrupts.
1655                  */
1656                 ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1657                 if (ret < 0) {
1658                         dev_err(&slave->dev,
1659                                 "SDW_SCP_INT1 recheck read failed:%d\n", ret);
1660                         goto io_err;
1661                 }
1662                 _buf = ret;
1663
1664                 ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, _buf2);
1665                 if (ret < 0) {
1666                         dev_err(&slave->dev,
1667                                 "SDW_SCP_INT2/3 recheck read failed:%d\n", ret);
1668                         goto io_err;
1669                 }
1670
1671                 if (slave->prop.is_sdca) {
1672                         ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1673                         if (ret < 0) {
1674                                 dev_err(&slave->dev,
1675                                         "SDW_DP0_INT recheck read failed:%d\n", ret);
1676                                 goto io_err;
1677                         }
1678                         sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1679                 }
1680
1681                 /*
1682                  * Make sure no interrupts are pending, but filter to limit loop
1683                  * to interrupts identified in the first status read
1684                  */
1685                 buf &= _buf;
1686                 buf2[0] &= _buf2[0];
1687                 buf2[1] &= _buf2[1];
1688                 stat = buf || buf2[0] || buf2[1] || sdca_cascade;
1689
1690                 /*
1691                  * Exit loop if Slave is continuously in ALERT state even
1692                  * after servicing the interrupt multiple times.
1693                  */
1694                 count++;
1695
1696                 /* we can get alerts while processing so keep retrying */
1697         } while (stat != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
1698
1699         if (count == SDW_READ_INTR_CLEAR_RETRY)
1700                 dev_warn(&slave->dev, "Reached MAX_RETRY on alert read\n");
1701
1702 io_err:
1703         pm_runtime_mark_last_busy(&slave->dev);
1704         pm_runtime_put_autosuspend(&slave->dev);
1705
1706         return ret;
1707 }
1708
1709 static int sdw_update_slave_status(struct sdw_slave *slave,
1710                                    enum sdw_slave_status status)
1711 {
1712         int ret = 0;
1713
1714         mutex_lock(&slave->sdw_dev_lock);
1715
1716         if (slave->probed) {
1717                 struct device *dev = &slave->dev;
1718                 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
1719
1720                 if (drv->ops && drv->ops->update_status)
1721                         ret = drv->ops->update_status(slave, status);
1722         }
1723
1724         mutex_unlock(&slave->sdw_dev_lock);
1725
1726         return ret;
1727 }
1728
1729 /**
1730  * sdw_handle_slave_status() - Handle Slave status
1731  * @bus: SDW bus instance
1732  * @status: Status for all Slave(s)
1733  */
1734 int sdw_handle_slave_status(struct sdw_bus *bus,
1735                             enum sdw_slave_status status[])
1736 {
1737         enum sdw_slave_status prev_status;
1738         struct sdw_slave *slave;
1739         bool attached_initializing;
1740         int i, ret = 0;
1741
1742         /* first check if any Slaves fell off the bus */
1743         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1744                 mutex_lock(&bus->bus_lock);
1745                 if (test_bit(i, bus->assigned) == false) {
1746                         mutex_unlock(&bus->bus_lock);
1747                         continue;
1748                 }
1749                 mutex_unlock(&bus->bus_lock);
1750
1751                 slave = sdw_get_slave(bus, i);
1752                 if (!slave)
1753                         continue;
1754
1755                 if (status[i] == SDW_SLAVE_UNATTACHED &&
1756                     slave->status != SDW_SLAVE_UNATTACHED) {
1757                         dev_warn(&slave->dev, "Slave %d state check1: UNATTACHED, status was %d\n",
1758                                  i, slave->status);
1759                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1760                 }
1761         }
1762
1763         if (status[0] == SDW_SLAVE_ATTACHED) {
1764                 dev_dbg(bus->dev, "Slave attached, programming device number\n");
1765                 ret = sdw_program_device_num(bus);
1766                 if (ret < 0)
1767                         dev_err(bus->dev, "Slave attach failed: %d\n", ret);
1768                 /*
1769                  * programming a device number will have side effects,
1770                  * so we deal with other devices at a later time
1771                  */
1772                 return ret;
1773         }
1774
1775         /* Continue to check other slave statuses */
1776         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1777                 mutex_lock(&bus->bus_lock);
1778                 if (test_bit(i, bus->assigned) == false) {
1779                         mutex_unlock(&bus->bus_lock);
1780                         continue;
1781                 }
1782                 mutex_unlock(&bus->bus_lock);
1783
1784                 slave = sdw_get_slave(bus, i);
1785                 if (!slave)
1786                         continue;
1787
1788                 attached_initializing = false;
1789
1790                 switch (status[i]) {
1791                 case SDW_SLAVE_UNATTACHED:
1792                         if (slave->status == SDW_SLAVE_UNATTACHED)
1793                                 break;
1794
1795                         dev_warn(&slave->dev, "Slave %d state check2: UNATTACHED, status was %d\n",
1796                                  i, slave->status);
1797
1798                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1799                         break;
1800
1801                 case SDW_SLAVE_ALERT:
1802                         ret = sdw_handle_slave_alerts(slave);
1803                         if (ret < 0)
1804                                 dev_err(&slave->dev,
1805                                         "Slave %d alert handling failed: %d\n",
1806                                         i, ret);
1807                         break;
1808
1809                 case SDW_SLAVE_ATTACHED:
1810                         if (slave->status == SDW_SLAVE_ATTACHED)
1811                                 break;
1812
1813                         prev_status = slave->status;
1814                         sdw_modify_slave_status(slave, SDW_SLAVE_ATTACHED);
1815
1816                         if (prev_status == SDW_SLAVE_ALERT)
1817                                 break;
1818
1819                         attached_initializing = true;
1820
1821                         ret = sdw_initialize_slave(slave);
1822                         if (ret < 0)
1823                                 dev_err(&slave->dev,
1824                                         "Slave %d initialization failed: %d\n",
1825                                         i, ret);
1826
1827                         break;
1828
1829                 default:
1830                         dev_err(&slave->dev, "Invalid slave %d status:%d\n",
1831                                 i, status[i]);
1832                         break;
1833                 }
1834
1835                 ret = sdw_update_slave_status(slave, status[i]);
1836                 if (ret < 0)
1837                         dev_err(&slave->dev,
1838                                 "Update Slave status failed:%d\n", ret);
1839                 if (attached_initializing) {
1840                         dev_dbg(&slave->dev,
1841                                 "%s: signaling initialization completion for Slave %d\n",
1842                                 __func__, slave->dev_num);
1843
1844                         complete(&slave->initialization_complete);
1845
1846                         /*
1847                          * If the manager became pm_runtime active, the peripherals will be
1848                          * restarted and attach, but their pm_runtime status may remain
1849                          * suspended. If the 'update_slave_status' callback initiates
1850                          * any sort of deferred processing, this processing would not be
1851                          * cancelled on pm_runtime suspend.
1852                          * To avoid such zombie states, we queue a request to resume.
1853                          * This would be a no-op in case the peripheral was being resumed
1854                          * by e.g. the ALSA/ASoC framework.
1855                          */
1856                         pm_request_resume(&slave->dev);
1857                 }
1858         }
1859
1860         return ret;
1861 }
1862 EXPORT_SYMBOL(sdw_handle_slave_status);
1863
1864 void sdw_clear_slave_status(struct sdw_bus *bus, u32 request)
1865 {
1866         struct sdw_slave *slave;
1867         int i;
1868
1869         /* Check all non-zero devices */
1870         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1871                 mutex_lock(&bus->bus_lock);
1872                 if (test_bit(i, bus->assigned) == false) {
1873                         mutex_unlock(&bus->bus_lock);
1874                         continue;
1875                 }
1876                 mutex_unlock(&bus->bus_lock);
1877
1878                 slave = sdw_get_slave(bus, i);
1879                 if (!slave)
1880                         continue;
1881
1882                 if (slave->status != SDW_SLAVE_UNATTACHED) {
1883                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1884                         slave->first_interrupt_done = false;
1885                         sdw_update_slave_status(slave, SDW_SLAVE_UNATTACHED);
1886                 }
1887
1888                 /* keep track of request, used in pm_runtime resume */
1889                 slave->unattach_request = request;
1890         }
1891 }
1892 EXPORT_SYMBOL(sdw_clear_slave_status);