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         ret = sdw_transfer(slave->bus, &msg);
 394         if (slave->is_mockup_device)
 395                 ret = 0;
 396         return ret;
 397 }
 398
 399 static int
 400 sdw_nwrite_no_pm(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 401 {
 402         struct sdw_msg msg;
 403         int ret;
 404
 405         ret = sdw_fill_msg(&msg, slave, addr, count,
 406                            slave->dev_num, SDW_MSG_FLAG_WRITE, (u8 *)val);
 407         if (ret < 0)
 408                 return ret;
 409
 410         ret = sdw_transfer(slave->bus, &msg);
 411         if (slave->is_mockup_device)
 412                 ret = 0;
 413         return ret;
 414 }
 415
 416 int sdw_write_no_pm(struct sdw_slave *slave, u32 addr, u8 value)
 417 {
 418         return sdw_nwrite_no_pm(slave, addr, 1, &value);
 419 }
 420 EXPORT_SYMBOL(sdw_write_no_pm);
 421
 422 static int
 423 sdw_bread_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr)
 424 {
 425         struct sdw_msg msg;
 426         u8 buf;
 427         int ret;
 428
 429         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 430                            SDW_MSG_FLAG_READ, &buf);
 431         if (ret < 0)
 432                 return ret;
 433
 434         ret = sdw_transfer(bus, &msg);
 435         if (ret < 0)
 436                 return ret;
 437
 438         return buf;
 439 }
 440
 441 static int
 442 sdw_bwrite_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 443 {
 444         struct sdw_msg msg;
 445         int ret;
 446
 447         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 448                            SDW_MSG_FLAG_WRITE, &value);
 449         if (ret < 0)
 450                 return ret;
 451
 452         return sdw_transfer(bus, &msg);
 453 }
 454
 455 int sdw_bread_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr)
 456 {
 457         struct sdw_msg msg;
 458         u8 buf;
 459         int ret;
 460
 461         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 462                            SDW_MSG_FLAG_READ, &buf);
 463         if (ret < 0)
 464                 return ret;
 465
 466         ret = sdw_transfer_unlocked(bus, &msg);
 467         if (ret < 0)
 468                 return ret;
 469
 470         return buf;
 471 }
 472 EXPORT_SYMBOL(sdw_bread_no_pm_unlocked);
 473
 474 int sdw_bwrite_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 475 {
 476         struct sdw_msg msg;
 477         int ret;
 478
 479         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 480                            SDW_MSG_FLAG_WRITE, &value);
 481         if (ret < 0)
 482                 return ret;
 483
 484         return sdw_transfer_unlocked(bus, &msg);
 485 }
 486 EXPORT_SYMBOL(sdw_bwrite_no_pm_unlocked);
 487
 488 int sdw_read_no_pm(struct sdw_slave *slave, u32 addr)
 489 {
 490         u8 buf;
 491         int ret;
 492
 493         ret = sdw_nread_no_pm(slave, addr, 1, &buf);
 494         if (ret < 0)
 495                 return ret;
 496         else
 497                 return buf;
 498 }
 499 EXPORT_SYMBOL(sdw_read_no_pm);
 500
 501 int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 502 {
 503         int tmp;
 504
 505         tmp = sdw_read_no_pm(slave, addr);
 506         if (tmp < 0)
 507                 return tmp;
 508
 509         tmp = (tmp & ~mask) | val;
 510         return sdw_write_no_pm(slave, addr, tmp);
 511 }
 512 EXPORT_SYMBOL(sdw_update_no_pm);
 513
 514 /* Read-Modify-Write Slave register */
 515 int sdw_update(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 516 {
 517         int tmp;
 518
 519         tmp = sdw_read(slave, addr);
 520         if (tmp < 0)
 521                 return tmp;
 522
 523         tmp = (tmp & ~mask) | val;
 524         return sdw_write(slave, addr, tmp);
 525 }
 526 EXPORT_SYMBOL(sdw_update);
 527
 528 /**
 529  * sdw_nread() - Read "n" contiguous SDW Slave registers
 530  * @slave: SDW Slave
 531  * @addr: Register address
 532  * @count: length
 533  * @val: Buffer for values to be read
 534  */
 535 int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 536 {
 537         int ret;
 538
 539         ret = pm_runtime_resume_and_get(&slave->dev);
 540         if (ret < 0 && ret != -EACCES)
 541                 return ret;
 542
 543         ret = sdw_nread_no_pm(slave, addr, count, val);
 544
 545         pm_runtime_mark_last_busy(&slave->dev);
 546         pm_runtime_put(&slave->dev);
 547
 548         return ret;
 549 }
 550 EXPORT_SYMBOL(sdw_nread);
 551
 552 /**
 553  * sdw_nwrite() - Write "n" contiguous SDW Slave registers
 554  * @slave: SDW Slave
 555  * @addr: Register address
 556  * @count: length
 557  * @val: Buffer for values to be written
 558  */
 559 int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 560 {
 561         int ret;
 562
 563         ret = pm_runtime_resume_and_get(&slave->dev);
 564         if (ret < 0 && ret != -EACCES)
 565                 return ret;
 566
 567         ret = sdw_nwrite_no_pm(slave, addr, count, val);
 568
 569         pm_runtime_mark_last_busy(&slave->dev);
 570         pm_runtime_put(&slave->dev);
 571
 572         return ret;
 573 }
 574 EXPORT_SYMBOL(sdw_nwrite);
 575
 576 /**
 577  * sdw_read() - Read a SDW Slave register
 578  * @slave: SDW Slave
 579  * @addr: Register address
 580  */
 581 int sdw_read(struct sdw_slave *slave, u32 addr)
 582 {
 583         u8 buf;
 584         int ret;
 585
 586         ret = sdw_nread(slave, addr, 1, &buf);
 587         if (ret < 0)
 588                 return ret;
 589
 590         return buf;
 591 }
 592 EXPORT_SYMBOL(sdw_read);
 593
 594 /**
 595  * sdw_write() - Write a SDW Slave register
 596  * @slave: SDW Slave
 597  * @addr: Register address
 598  * @value: Register value
 599  */
 600 int sdw_write(struct sdw_slave *slave, u32 addr, u8 value)
 601 {
 602         return sdw_nwrite(slave, addr, 1, &value);
 603 }
 604 EXPORT_SYMBOL(sdw_write);
 605
 606 /*
 607  * SDW alert handling
 608  */
 609
 610 /* called with bus_lock held */
 611 static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i)
 612 {
 613         struct sdw_slave *slave;
 614
 615         list_for_each_entry(slave, &bus->slaves, node) {
 616                 if (slave->dev_num == i)
 617                         return slave;
 618         }
 619
 620         return NULL;
 621 }
 622
 623 int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id)
 624 {
 625         if (slave->id.mfg_id != id.mfg_id ||
 626             slave->id.part_id != id.part_id ||
 627             slave->id.class_id != id.class_id ||
 628             (slave->id.unique_id != SDW_IGNORED_UNIQUE_ID &&
 629              slave->id.unique_id != id.unique_id))
 630                 return -ENODEV;
 631
 632         return 0;
 633 }
 634 EXPORT_SYMBOL(sdw_compare_devid);
 635
 636 /* called with bus_lock held */
 637 static int sdw_get_device_num(struct sdw_slave *slave)
 638 {
 639         int bit;
 640
 641         bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES);
 642         if (bit == SDW_MAX_DEVICES) {
 643                 bit = -ENODEV;
 644                 goto err;
 645         }
 646
 647         /*
 648          * Do not update dev_num in Slave data structure here,
 649          * Update once program dev_num is successful
 650          */
 651         set_bit(bit, slave->bus->assigned);
 652
 653 err:
 654         return bit;
 655 }
 656
 657 static int sdw_assign_device_num(struct sdw_slave *slave)
 658 {
 659         struct sdw_bus *bus = slave->bus;
 660         int ret, dev_num;
 661         bool new_device = false;
 662
 663         /* check first if device number is assigned, if so reuse that */
 664         if (!slave->dev_num) {
 665                 if (!slave->dev_num_sticky) {
 666                         mutex_lock(&slave->bus->bus_lock);
 667                         dev_num = sdw_get_device_num(slave);
 668                         mutex_unlock(&slave->bus->bus_lock);
 669                         if (dev_num < 0) {
 670                                 dev_err(bus->dev, "Get dev_num failed: %d\n",
 671                                         dev_num);
 672                                 return dev_num;
 673                         }
 674                         slave->dev_num = dev_num;
 675                         slave->dev_num_sticky = dev_num;
 676                         new_device = true;
 677                 } else {
 678                         slave->dev_num = slave->dev_num_sticky;
 679                 }
 680         }
 681
 682         if (!new_device)
 683                 dev_dbg(bus->dev,
 684                         "Slave already registered, reusing dev_num:%d\n",
 685                         slave->dev_num);
 686
 687         /* Clear the slave->dev_num to transfer message on device 0 */
 688         dev_num = slave->dev_num;
 689         slave->dev_num = 0;
 690
 691         ret = sdw_write_no_pm(slave, SDW_SCP_DEVNUMBER, dev_num);
 692         if (ret < 0) {
 693                 dev_err(bus->dev, "Program device_num %d failed: %d\n",
 694                         dev_num, ret);
 695                 return ret;
 696         }
 697
 698         /* After xfer of msg, restore dev_num */
 699         slave->dev_num = slave->dev_num_sticky;
 700
 701         return 0;
 702 }
 703
 704 void sdw_extract_slave_id(struct sdw_bus *bus,
 705                           u64 addr, struct sdw_slave_id *id)
 706 {
 707         dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr);
 708
 709         id->sdw_version = SDW_VERSION(addr);
 710         id->unique_id = SDW_UNIQUE_ID(addr);
 711         id->mfg_id = SDW_MFG_ID(addr);
 712         id->part_id = SDW_PART_ID(addr);
 713         id->class_id = SDW_CLASS_ID(addr);
 714
 715         dev_dbg(bus->dev,
 716                 "SDW Slave class_id 0x%02x, mfg_id 0x%04x, part_id 0x%04x, unique_id 0x%x, version 0x%x\n",
 717                 id->class_id, id->mfg_id, id->part_id, id->unique_id, id->sdw_version);
 718 }
 719 EXPORT_SYMBOL(sdw_extract_slave_id);
 720
 721 static int sdw_program_device_num(struct sdw_bus *bus)
 722 {
 723         u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0};
 724         struct sdw_slave *slave, *_s;
 725         struct sdw_slave_id id;
 726         struct sdw_msg msg;
 727         bool found;
 728         int count = 0, ret;
 729         u64 addr;
 730
 731         /* No Slave, so use raw xfer api */
 732         ret = sdw_fill_msg(&msg, NULL, SDW_SCP_DEVID_0,
 733                            SDW_NUM_DEV_ID_REGISTERS, 0, SDW_MSG_FLAG_READ, buf);
 734         if (ret < 0)
 735                 return ret;
 736
 737         do {
 738                 ret = sdw_transfer(bus, &msg);
 739                 if (ret == -ENODATA) { /* end of device id reads */
 740                         dev_dbg(bus->dev, "No more devices to enumerate\n");
 741                         ret = 0;
 742                         break;
 743                 }
 744                 if (ret < 0) {
 745                         dev_err(bus->dev, "DEVID read fail:%d\n", ret);
 746                         break;
 747                 }
 748
 749                 /*
 750                  * Construct the addr and extract. Cast the higher shift
 751                  * bits to avoid truncation due to size limit.
 752                  */
 753                 addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) |
 754                         ((u64)buf[2] << 24) | ((u64)buf[1] << 32) |
 755                         ((u64)buf[0] << 40);
 756
 757                 sdw_extract_slave_id(bus, addr, &id);
 758
 759                 found = false;
 760                 /* Now compare with entries */
 761                 list_for_each_entry_safe(slave, _s, &bus->slaves, node) {
 762                         if (sdw_compare_devid(slave, id) == 0) {
 763                                 found = true;
 764
 765                                 /*
 766                                  * Assign a new dev_num to this Slave and
 767                                  * not mark it present. It will be marked
 768                                  * present after it reports ATTACHED on new
 769                                  * dev_num
 770                                  */
 771                                 ret = sdw_assign_device_num(slave);
 772                                 if (ret < 0) {
 773                                         dev_err(bus->dev,
 774                                                 "Assign dev_num failed:%d\n",
 775                                                 ret);
 776                                         return ret;
 777                                 }
 778
 779                                 break;
 780                         }
 781                 }
 782
 783                 if (!found) {
 784                         /* TODO: Park this device in Group 13 */
 785
 786                         /*
 787                          * add Slave device even if there is no platform
 788                          * firmware description. There will be no driver probe
 789                          * but the user/integration will be able to see the
 790                          * device, enumeration status and device number in sysfs
 791                          */
 792                         sdw_slave_add(bus, &id, NULL);
 793
 794                         dev_err(bus->dev, "Slave Entry not found\n");
 795                 }
 796
 797                 count++;
 798
 799                 /*
 800                  * Check till error out or retry (count) exhausts.
 801                  * Device can drop off and rejoin during enumeration
 802                  * so count till twice the bound.
 803                  */
 804
 805         } while (ret == 0 && count < (SDW_MAX_DEVICES * 2));
 806
 807         return ret;
 808 }
 809
 810 static void sdw_modify_slave_status(struct sdw_slave *slave,
 811                                     enum sdw_slave_status status)
 812 {
 813         struct sdw_bus *bus = slave->bus;
 814
 815         mutex_lock(&bus->bus_lock);
 816
 817         dev_vdbg(bus->dev,
 818                  "%s: changing status slave %d status %d new status %d\n",
 819                  __func__, slave->dev_num, slave->status, status);
 820
 821         if (status == SDW_SLAVE_UNATTACHED) {
 822                 dev_dbg(&slave->dev,
 823                         "%s: initializing enumeration and init completion for Slave %d\n",
 824                         __func__, slave->dev_num);
 825
 826                 init_completion(&slave->enumeration_complete);
 827                 init_completion(&slave->initialization_complete);
 828
 829         } else if ((status == SDW_SLAVE_ATTACHED) &&
 830                    (slave->status == SDW_SLAVE_UNATTACHED)) {
 831                 dev_dbg(&slave->dev,
 832                         "%s: signaling enumeration completion for Slave %d\n",
 833                         __func__, slave->dev_num);
 834
 835                 complete(&slave->enumeration_complete);
 836         }
 837         slave->status = status;
 838         mutex_unlock(&bus->bus_lock);
 839 }
 840
 841 static int sdw_slave_clk_stop_callback(struct sdw_slave *slave,
 842                                        enum sdw_clk_stop_mode mode,
 843                                        enum sdw_clk_stop_type type)
 844 {
 845         int ret;
 846
 847         if (slave->ops && slave->ops->clk_stop) {
 848                 ret = slave->ops->clk_stop(slave, mode, type);
 849                 if (ret < 0)
 850                         return ret;
 851         }
 852
 853         return 0;
 854 }
 855
 856 static int sdw_slave_clk_stop_prepare(struct sdw_slave *slave,
 857                                       enum sdw_clk_stop_mode mode,
 858                                       bool prepare)
 859 {
 860         bool wake_en;
 861         u32 val = 0;
 862         int ret;
 863
 864         wake_en = slave->prop.wake_capable;
 865
 866         if (prepare) {
 867                 val = SDW_SCP_SYSTEMCTRL_CLK_STP_PREP;
 868
 869                 if (mode == SDW_CLK_STOP_MODE1)
 870                         val |= SDW_SCP_SYSTEMCTRL_CLK_STP_MODE1;
 871
 872                 if (wake_en)
 873                         val |= SDW_SCP_SYSTEMCTRL_WAKE_UP_EN;
 874         } else {
 875                 ret = sdw_read_no_pm(slave, SDW_SCP_SYSTEMCTRL);
 876                 if (ret < 0) {
 877                         if (ret != -ENODATA)
 878                                 dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL read failed:%d\n", ret);
 879                         return ret;
 880                 }
 881                 val = ret;
 882                 val &= ~(SDW_SCP_SYSTEMCTRL_CLK_STP_PREP);
 883         }
 884
 885         ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val);
 886
 887         if (ret < 0 && ret != -ENODATA)
 888                 dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL write failed:%d\n", ret);
 889
 890         return ret;
 891 }
 892
 893 static int sdw_bus_wait_for_clk_prep_deprep(struct sdw_bus *bus, u16 dev_num)
 894 {
 895         int retry = bus->clk_stop_timeout;
 896         int val;
 897
 898         do {
 899                 val = sdw_bread_no_pm(bus, dev_num, SDW_SCP_STAT);
 900                 if (val < 0) {
 901                         if (val != -ENODATA)
 902                                 dev_err(bus->dev, "SDW_SCP_STAT bread failed:%d\n", val);
 903                         return val;
 904                 }
 905                 val &= SDW_SCP_STAT_CLK_STP_NF;
 906                 if (!val) {
 907                         dev_dbg(bus->dev, "clock stop prep/de-prep done slave:%d\n",
 908                                 dev_num);
 909                         return 0;
 910                 }
 911
 912                 usleep_range(1000, 1500);
 913                 retry--;
 914         } while (retry);
 915
 916         dev_err(bus->dev, "clock stop prep/de-prep failed slave:%d\n",
 917                 dev_num);
 918
 919         return -ETIMEDOUT;
 920 }
 921
 922 /**
 923  * sdw_bus_prep_clk_stop: prepare Slave(s) for clock stop
 924  *
 925  * @bus: SDW bus instance
 926  *
 927  * Query Slave for clock stop mode and prepare for that mode.
 928  */
 929 int sdw_bus_prep_clk_stop(struct sdw_bus *bus)
 930 {
 931         bool simple_clk_stop = true;
 932         struct sdw_slave *slave;
 933         bool is_slave = false;
 934         int ret = 0;
 935
 936         /*
 937          * In order to save on transition time, prepare
 938          * each Slave and then wait for all Slave(s) to be
 939          * prepared for clock stop.
 940          * If one of the Slave devices has lost sync and
 941          * replies with Command Ignored/-ENODATA, we continue
 942          * the loop
 943          */
 944         list_for_each_entry(slave, &bus->slaves, node) {
 945                 if (!slave->dev_num)
 946                         continue;
 947
 948                 if (slave->status != SDW_SLAVE_ATTACHED &&
 949                     slave->status != SDW_SLAVE_ALERT)
 950                         continue;
 951
 952                 /* Identify if Slave(s) are available on Bus */
 953                 is_slave = true;
 954
 955                 ret = sdw_slave_clk_stop_callback(slave,
 956                                                   SDW_CLK_STOP_MODE0,
 957                                                   SDW_CLK_PRE_PREPARE);
 958                 if (ret < 0 && ret != -ENODATA) {
 959                         dev_err(&slave->dev, "clock stop pre-prepare cb failed:%d\n", ret);
 960                         return ret;
 961                 }
 962
 963                 /* Only prepare a Slave device if needed */
 964                 if (!slave->prop.simple_clk_stop_capable) {
 965                         simple_clk_stop = false;
 966
 967                         ret = sdw_slave_clk_stop_prepare(slave,
 968                                                          SDW_CLK_STOP_MODE0,
 969                                                          true);
 970                         if (ret < 0 && ret != -ENODATA) {
 971                                 dev_err(&slave->dev, "clock stop prepare failed:%d\n", ret);
 972                                 return ret;
 973                         }
 974                 }
 975         }
 976
 977         /* Skip remaining clock stop preparation if no Slave is attached */
 978         if (!is_slave)
 979                 return 0;
 980
 981         /*
 982          * Don't wait for all Slaves to be ready if they follow the simple
 983          * state machine
 984          */
 985         if (!simple_clk_stop) {
 986                 ret = sdw_bus_wait_for_clk_prep_deprep(bus,
 987                                                        SDW_BROADCAST_DEV_NUM);
 988                 /*
 989                  * if there are no Slave devices present and the reply is
 990                  * Command_Ignored/-ENODATA, we don't need to continue with the
 991                  * flow and can just return here. The error code is not modified
 992                  * and its handling left as an exercise for the caller.
 993                  */
 994                 if (ret < 0)
 995                         return ret;
 996         }
 997
 998         /* Inform slaves that prep is done */
 999         list_for_each_entry(slave, &bus->slaves, node) {
1000                 if (!slave->dev_num)
1001                         continue;
1002
1003                 if (slave->status != SDW_SLAVE_ATTACHED &&
1004                     slave->status != SDW_SLAVE_ALERT)
1005                         continue;
1006
1007                 ret = sdw_slave_clk_stop_callback(slave,
1008                                                   SDW_CLK_STOP_MODE0,
1009                                                   SDW_CLK_POST_PREPARE);
1010
1011                 if (ret < 0 && ret != -ENODATA) {
1012                         dev_err(&slave->dev, "clock stop post-prepare cb failed:%d\n", ret);
1013                         return ret;
1014                 }
1015         }
1016
1017         return 0;
1018 }
1019 EXPORT_SYMBOL(sdw_bus_prep_clk_stop);
1020
1021 /**
1022  * sdw_bus_clk_stop: stop bus clock
1023  *
1024  * @bus: SDW bus instance
1025  *
1026  * After preparing the Slaves for clock stop, stop the clock by broadcasting
1027  * write to SCP_CTRL register.
1028  */
1029 int sdw_bus_clk_stop(struct sdw_bus *bus)
1030 {
1031         int ret;
1032
1033         /*
1034          * broadcast clock stop now, attached Slaves will ACK this,
1035          * unattached will ignore
1036          */
1037         ret = sdw_bwrite_no_pm(bus, SDW_BROADCAST_DEV_NUM,
1038                                SDW_SCP_CTRL, SDW_SCP_CTRL_CLK_STP_NOW);
1039         if (ret < 0) {
1040                 if (ret != -ENODATA)
1041                         dev_err(bus->dev, "ClockStopNow Broadcast msg failed %d\n", ret);
1042                 return ret;
1043         }
1044
1045         return 0;
1046 }
1047 EXPORT_SYMBOL(sdw_bus_clk_stop);
1048
1049 /**
1050  * sdw_bus_exit_clk_stop: Exit clock stop mode
1051  *
1052  * @bus: SDW bus instance
1053  *
1054  * This De-prepares the Slaves by exiting Clock Stop Mode 0. For the Slaves
1055  * exiting Clock Stop Mode 1, they will be de-prepared after they enumerate
1056  * back.
1057  */
1058 int sdw_bus_exit_clk_stop(struct sdw_bus *bus)
1059 {
1060         bool simple_clk_stop = true;
1061         struct sdw_slave *slave;
1062         bool is_slave = false;
1063         int ret;
1064
1065         /*
1066          * In order to save on transition time, de-prepare
1067          * each Slave and then wait for all Slave(s) to be
1068          * de-prepared after clock resume.
1069          */
1070         list_for_each_entry(slave, &bus->slaves, node) {
1071                 if (!slave->dev_num)
1072                         continue;
1073
1074                 if (slave->status != SDW_SLAVE_ATTACHED &&
1075                     slave->status != SDW_SLAVE_ALERT)
1076                         continue;
1077
1078                 /* Identify if Slave(s) are available on Bus */
1079                 is_slave = true;
1080
1081                 ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1082                                                   SDW_CLK_PRE_DEPREPARE);
1083                 if (ret < 0)
1084                         dev_warn(&slave->dev, "clock stop pre-deprepare cb failed:%d\n", ret);
1085
1086                 /* Only de-prepare a Slave device if needed */
1087                 if (!slave->prop.simple_clk_stop_capable) {
1088                         simple_clk_stop = false;
1089
1090                         ret = sdw_slave_clk_stop_prepare(slave, SDW_CLK_STOP_MODE0,
1091                                                          false);
1092
1093                         if (ret < 0)
1094                                 dev_warn(&slave->dev, "clock stop deprepare failed:%d\n", ret);
1095                 }
1096         }
1097
1098         /* Skip remaining clock stop de-preparation if no Slave is attached */
1099         if (!is_slave)
1100                 return 0;
1101
1102         /*
1103          * Don't wait for all Slaves to be ready if they follow the simple
1104          * state machine
1105          */
1106         if (!simple_clk_stop) {
1107                 ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM);
1108                 if (ret < 0)
1109                         dev_warn(bus->dev, "clock stop deprepare wait failed:%d\n", ret);
1110         }
1111
1112         list_for_each_entry(slave, &bus->slaves, node) {
1113                 if (!slave->dev_num)
1114                         continue;
1115
1116                 if (slave->status != SDW_SLAVE_ATTACHED &&
1117                     slave->status != SDW_SLAVE_ALERT)
1118                         continue;
1119
1120                 ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1121                                                   SDW_CLK_POST_DEPREPARE);
1122                 if (ret < 0)
1123                         dev_warn(&slave->dev, "clock stop post-deprepare cb failed:%d\n", ret);
1124         }
1125
1126         return 0;
1127 }
1128 EXPORT_SYMBOL(sdw_bus_exit_clk_stop);
1129
1130 int sdw_configure_dpn_intr(struct sdw_slave *slave,
1131                            int port, bool enable, int mask)
1132 {
1133         u32 addr;
1134         int ret;
1135         u8 val = 0;
1136
1137         if (slave->bus->params.s_data_mode != SDW_PORT_DATA_MODE_NORMAL) {
1138                 dev_dbg(&slave->dev, "TEST FAIL interrupt %s\n",
1139                         enable ? "on" : "off");
1140                 mask |= SDW_DPN_INT_TEST_FAIL;
1141         }
1142
1143         addr = SDW_DPN_INTMASK(port);
1144
1145         /* Set/Clear port ready interrupt mask */
1146         if (enable) {
1147                 val |= mask;
1148                 val |= SDW_DPN_INT_PORT_READY;
1149         } else {
1150                 val &= ~(mask);
1151                 val &= ~SDW_DPN_INT_PORT_READY;
1152         }
1153
1154         ret = sdw_update(slave, addr, (mask | SDW_DPN_INT_PORT_READY), val);
1155         if (ret < 0)
1156                 dev_err(&slave->dev,
1157                         "SDW_DPN_INTMASK write failed:%d\n", val);
1158
1159         return ret;
1160 }
1161
1162 static int sdw_slave_set_frequency(struct sdw_slave *slave)
1163 {
1164         u32 mclk_freq = slave->bus->prop.mclk_freq;
1165         u32 curr_freq = slave->bus->params.curr_dr_freq >> 1;
1166         unsigned int scale;
1167         u8 scale_index;
1168         u8 base;
1169         int ret;
1170
1171         /*
1172          * frequency base and scale registers are required for SDCA
1173          * devices. They may also be used for 1.2+/non-SDCA devices,
1174          * but we will need a DisCo property to cover this case
1175          */
1176         if (!slave->id.class_id)
1177                 return 0;
1178
1179         if (!mclk_freq) {
1180                 dev_err(&slave->dev,
1181                         "no bus MCLK, cannot set SDW_SCP_BUS_CLOCK_BASE\n");
1182                 return -EINVAL;
1183         }
1184
1185         /*
1186          * map base frequency using Table 89 of SoundWire 1.2 spec.
1187          * The order of the tests just follows the specification, this
1188          * is not a selection between possible values or a search for
1189          * the best value but just a mapping.  Only one case per platform
1190          * is relevant.
1191          * Some BIOS have inconsistent values for mclk_freq but a
1192          * correct root so we force the mclk_freq to avoid variations.
1193          */
1194         if (!(19200000 % mclk_freq)) {
1195                 mclk_freq = 19200000;
1196                 base = SDW_SCP_BASE_CLOCK_19200000_HZ;
1197         } else if (!(24000000 % mclk_freq)) {
1198                 mclk_freq = 24000000;
1199                 base = SDW_SCP_BASE_CLOCK_24000000_HZ;
1200         } else if (!(24576000 % mclk_freq)) {
1201                 mclk_freq = 24576000;
1202                 base = SDW_SCP_BASE_CLOCK_24576000_HZ;
1203         } else if (!(22579200 % mclk_freq)) {
1204                 mclk_freq = 22579200;
1205                 base = SDW_SCP_BASE_CLOCK_22579200_HZ;
1206         } else if (!(32000000 % mclk_freq)) {
1207                 mclk_freq = 32000000;
1208                 base = SDW_SCP_BASE_CLOCK_32000000_HZ;
1209         } else {
1210                 dev_err(&slave->dev,
1211                         "Unsupported clock base, mclk %d\n",
1212                         mclk_freq);
1213                 return -EINVAL;
1214         }
1215
1216         if (mclk_freq % curr_freq) {
1217                 dev_err(&slave->dev,
1218                         "mclk %d is not multiple of bus curr_freq %d\n",
1219                         mclk_freq, curr_freq);
1220                 return -EINVAL;
1221         }
1222
1223         scale = mclk_freq / curr_freq;
1224
1225         /*
1226          * map scale to Table 90 of SoundWire 1.2 spec - and check
1227          * that the scale is a power of two and maximum 64
1228          */
1229         scale_index = ilog2(scale);
1230
1231         if (BIT(scale_index) != scale || scale_index > 6) {
1232                 dev_err(&slave->dev,
1233                         "No match found for scale %d, bus mclk %d curr_freq %d\n",
1234                         scale, mclk_freq, curr_freq);
1235                 return -EINVAL;
1236         }
1237         scale_index++;
1238
1239         ret = sdw_write_no_pm(slave, SDW_SCP_BUS_CLOCK_BASE, base);
1240         if (ret < 0) {
1241                 dev_err(&slave->dev,
1242                         "SDW_SCP_BUS_CLOCK_BASE write failed:%d\n", ret);
1243                 return ret;
1244         }
1245
1246         /* initialize scale for both banks */
1247         ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B0, scale_index);
1248         if (ret < 0) {
1249                 dev_err(&slave->dev,
1250                         "SDW_SCP_BUSCLOCK_SCALE_B0 write failed:%d\n", ret);
1251                 return ret;
1252         }
1253         ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B1, scale_index);
1254         if (ret < 0)
1255                 dev_err(&slave->dev,
1256                         "SDW_SCP_BUSCLOCK_SCALE_B1 write failed:%d\n", ret);
1257
1258         dev_dbg(&slave->dev,
1259                 "Configured bus base %d, scale %d, mclk %d, curr_freq %d\n",
1260                 base, scale_index, mclk_freq, curr_freq);
1261
1262         return ret;
1263 }
1264
1265 static int sdw_initialize_slave(struct sdw_slave *slave)
1266 {
1267         struct sdw_slave_prop *prop = &slave->prop;
1268         int status;
1269         int ret;
1270         u8 val;
1271
1272         ret = sdw_slave_set_frequency(slave);
1273         if (ret < 0)
1274                 return ret;
1275
1276         if (slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH) {
1277                 /* Clear bus clash interrupt before enabling interrupt mask */
1278                 status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1279                 if (status < 0) {
1280                         dev_err(&slave->dev,
1281                                 "SDW_SCP_INT1 (BUS_CLASH) read failed:%d\n", status);
1282                         return status;
1283                 }
1284                 if (status & SDW_SCP_INT1_BUS_CLASH) {
1285                         dev_warn(&slave->dev, "Bus clash detected before INT mask is enabled\n");
1286                         ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_BUS_CLASH);
1287                         if (ret < 0) {
1288                                 dev_err(&slave->dev,
1289                                         "SDW_SCP_INT1 (BUS_CLASH) write failed:%d\n", ret);
1290                                 return ret;
1291                         }
1292                 }
1293         }
1294         if ((slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY) &&
1295             !(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY)) {
1296                 /* Clear parity interrupt before enabling interrupt mask */
1297                 status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1298                 if (status < 0) {
1299                         dev_err(&slave->dev,
1300                                 "SDW_SCP_INT1 (PARITY) read failed:%d\n", status);
1301                         return status;
1302                 }
1303                 if (status & SDW_SCP_INT1_PARITY) {
1304                         dev_warn(&slave->dev, "PARITY error detected before INT mask is enabled\n");
1305                         ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_PARITY);
1306                         if (ret < 0) {
1307                                 dev_err(&slave->dev,
1308                                         "SDW_SCP_INT1 (PARITY) write failed:%d\n", ret);
1309                                 return ret;
1310                         }
1311                 }
1312         }
1313
1314         /*
1315          * Set SCP_INT1_MASK register, typically bus clash and
1316          * implementation-defined interrupt mask. The Parity detection
1317          * may not always be correct on startup so its use is
1318          * device-dependent, it might e.g. only be enabled in
1319          * steady-state after a couple of frames.
1320          */
1321         val = slave->prop.scp_int1_mask;
1322
1323         /* Enable SCP interrupts */
1324         ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val);
1325         if (ret < 0) {
1326                 dev_err(&slave->dev,
1327                         "SDW_SCP_INTMASK1 write failed:%d\n", ret);
1328                 return ret;
1329         }
1330
1331         /* No need to continue if DP0 is not present */
1332         if (!slave->prop.dp0_prop)
1333                 return 0;
1334
1335         /* Enable DP0 interrupts */
1336         val = prop->dp0_prop->imp_def_interrupts;
1337         val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE;
1338
1339         ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val);
1340         if (ret < 0)
1341                 dev_err(&slave->dev,
1342                         "SDW_DP0_INTMASK read failed:%d\n", ret);
1343         return ret;
1344 }
1345
1346 static int sdw_handle_dp0_interrupt(struct sdw_slave *slave, u8 *slave_status)
1347 {
1348         u8 clear, impl_int_mask;
1349         int status, status2, ret, count = 0;
1350
1351         status = sdw_read_no_pm(slave, SDW_DP0_INT);
1352         if (status < 0) {
1353                 dev_err(&slave->dev,
1354                         "SDW_DP0_INT read failed:%d\n", status);
1355                 return status;
1356         }
1357
1358         do {
1359                 clear = status & ~SDW_DP0_INTERRUPTS;
1360
1361                 if (status & SDW_DP0_INT_TEST_FAIL) {
1362                         dev_err(&slave->dev, "Test fail for port 0\n");
1363                         clear |= SDW_DP0_INT_TEST_FAIL;
1364                 }
1365
1366                 /*
1367                  * Assumption: PORT_READY interrupt will be received only for
1368                  * ports implementing Channel Prepare state machine (CP_SM)
1369                  */
1370
1371                 if (status & SDW_DP0_INT_PORT_READY) {
1372                         complete(&slave->port_ready[0]);
1373                         clear |= SDW_DP0_INT_PORT_READY;
1374                 }
1375
1376                 if (status & SDW_DP0_INT_BRA_FAILURE) {
1377                         dev_err(&slave->dev, "BRA failed\n");
1378                         clear |= SDW_DP0_INT_BRA_FAILURE;
1379                 }
1380
1381                 impl_int_mask = SDW_DP0_INT_IMPDEF1 |
1382                         SDW_DP0_INT_IMPDEF2 | SDW_DP0_INT_IMPDEF3;
1383
1384                 if (status & impl_int_mask) {
1385                         clear |= impl_int_mask;
1386                         *slave_status = clear;
1387                 }
1388
1389                 /* clear the interrupts but don't touch reserved and SDCA_CASCADE fields */
1390                 ret = sdw_write_no_pm(slave, SDW_DP0_INT, clear);
1391                 if (ret < 0) {
1392                         dev_err(&slave->dev,
1393                                 "SDW_DP0_INT write failed:%d\n", ret);
1394                         return ret;
1395                 }
1396
1397                 /* Read DP0 interrupt again */
1398                 status2 = sdw_read_no_pm(slave, SDW_DP0_INT);
1399                 if (status2 < 0) {
1400                         dev_err(&slave->dev,
1401                                 "SDW_DP0_INT read failed:%d\n", status2);
1402                         return status2;
1403                 }
1404                 /* filter to limit loop to interrupts identified in the first status read */
1405                 status &= status2;
1406
1407                 count++;
1408
1409                 /* we can get alerts while processing so keep retrying */
1410         } while ((status & SDW_DP0_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1411
1412         if (count == SDW_READ_INTR_CLEAR_RETRY)
1413                 dev_warn(&slave->dev, "Reached MAX_RETRY on DP0 read\n");
1414
1415         return ret;
1416 }
1417
1418 static int sdw_handle_port_interrupt(struct sdw_slave *slave,
1419                                      int port, u8 *slave_status)
1420 {
1421         u8 clear, impl_int_mask;
1422         int status, status2, ret, count = 0;
1423         u32 addr;
1424
1425         if (port == 0)
1426                 return sdw_handle_dp0_interrupt(slave, slave_status);
1427
1428         addr = SDW_DPN_INT(port);
1429         status = sdw_read_no_pm(slave, addr);
1430         if (status < 0) {
1431                 dev_err(&slave->dev,
1432                         "SDW_DPN_INT read failed:%d\n", status);
1433
1434                 return status;
1435         }
1436
1437         do {
1438                 clear = status & ~SDW_DPN_INTERRUPTS;
1439
1440                 if (status & SDW_DPN_INT_TEST_FAIL) {
1441                         dev_err(&slave->dev, "Test fail for port:%d\n", port);
1442                         clear |= SDW_DPN_INT_TEST_FAIL;
1443                 }
1444
1445                 /*
1446                  * Assumption: PORT_READY interrupt will be received only
1447                  * for ports implementing CP_SM.
1448                  */
1449                 if (status & SDW_DPN_INT_PORT_READY) {
1450                         complete(&slave->port_ready[port]);
1451                         clear |= SDW_DPN_INT_PORT_READY;
1452                 }
1453
1454                 impl_int_mask = SDW_DPN_INT_IMPDEF1 |
1455                         SDW_DPN_INT_IMPDEF2 | SDW_DPN_INT_IMPDEF3;
1456
1457                 if (status & impl_int_mask) {
1458                         clear |= impl_int_mask;
1459                         *slave_status = clear;
1460                 }
1461
1462                 /* clear the interrupt but don't touch reserved fields */
1463                 ret = sdw_write_no_pm(slave, addr, clear);
1464                 if (ret < 0) {
1465                         dev_err(&slave->dev,
1466                                 "SDW_DPN_INT write failed:%d\n", ret);
1467                         return ret;
1468                 }
1469
1470                 /* Read DPN interrupt again */
1471                 status2 = sdw_read_no_pm(slave, addr);
1472                 if (status2 < 0) {
1473                         dev_err(&slave->dev,
1474                                 "SDW_DPN_INT read failed:%d\n", status2);
1475                         return status2;
1476                 }
1477                 /* filter to limit loop to interrupts identified in the first status read */
1478                 status &= status2;
1479
1480                 count++;
1481
1482                 /* we can get alerts while processing so keep retrying */
1483         } while ((status & SDW_DPN_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1484
1485         if (count == SDW_READ_INTR_CLEAR_RETRY)
1486                 dev_warn(&slave->dev, "Reached MAX_RETRY on port read");
1487
1488         return ret;
1489 }
1490
1491 static int sdw_handle_slave_alerts(struct sdw_slave *slave)
1492 {
1493         struct sdw_slave_intr_status slave_intr;
1494         u8 clear = 0, bit, port_status[15] = {0};
1495         int port_num, stat, ret, count = 0;
1496         unsigned long port;
1497         bool slave_notify;
1498         u8 sdca_cascade = 0;
1499         u8 buf, buf2[2], _buf, _buf2[2];
1500         bool parity_check;
1501         bool parity_quirk;
1502
1503         sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);
1504
1505         ret = pm_runtime_resume_and_get(&slave->dev);
1506         if (ret < 0 && ret != -EACCES) {
1507                 dev_err(&slave->dev, "Failed to resume device: %d\n", ret);
1508                 return ret;
1509         }
1510
1511         /* Read Intstat 1, Intstat 2 and Intstat 3 registers */
1512         ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1513         if (ret < 0) {
1514                 dev_err(&slave->dev,
1515                         "SDW_SCP_INT1 read failed:%d\n", ret);
1516                 goto io_err;
1517         }
1518         buf = ret;
1519
1520         ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2);
1521         if (ret < 0) {
1522                 dev_err(&slave->dev,
1523                         "SDW_SCP_INT2/3 read failed:%d\n", ret);
1524                 goto io_err;
1525         }
1526
1527         if (slave->prop.is_sdca) {
1528                 ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1529                 if (ret < 0) {
1530                         dev_err(&slave->dev,
1531                                 "SDW_DP0_INT read failed:%d\n", ret);
1532                         goto io_err;
1533                 }
1534                 sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1535         }
1536
1537         do {
1538                 slave_notify = false;
1539
1540                 /*
1541                  * Check parity, bus clash and Slave (impl defined)
1542                  * interrupt
1543                  */
1544                 if (buf & SDW_SCP_INT1_PARITY) {
1545                         parity_check = slave->prop.scp_int1_mask & SDW_SCP_INT1_PARITY;
1546                         parity_quirk = !slave->first_interrupt_done &&
1547                                 (slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY);
1548
1549                         if (parity_check && !parity_quirk)
1550                                 dev_err(&slave->dev, "Parity error detected\n");
1551                         clear |= SDW_SCP_INT1_PARITY;
1552                 }
1553
1554                 if (buf & SDW_SCP_INT1_BUS_CLASH) {
1555                         if (slave->prop.scp_int1_mask & SDW_SCP_INT1_BUS_CLASH)
1556                                 dev_err(&slave->dev, "Bus clash detected\n");
1557                         clear |= SDW_SCP_INT1_BUS_CLASH;
1558                 }
1559
1560                 /*
1561                  * When bus clash or parity errors are detected, such errors
1562                  * are unlikely to be recoverable errors.
1563                  * TODO: In such scenario, reset bus. Make this configurable
1564                  * via sysfs property with bus reset being the default.
1565                  */
1566
1567                 if (buf & SDW_SCP_INT1_IMPL_DEF) {
1568                         if (slave->prop.scp_int1_mask & SDW_SCP_INT1_IMPL_DEF) {
1569                                 dev_dbg(&slave->dev, "Slave impl defined interrupt\n");
1570                                 slave_notify = true;
1571                         }
1572                         clear |= SDW_SCP_INT1_IMPL_DEF;
1573                 }
1574
1575                 /* the SDCA interrupts are cleared in the codec driver .interrupt_callback() */
1576                 if (sdca_cascade)
1577                         slave_notify = true;
1578
1579                 /* Check port 0 - 3 interrupts */
1580                 port = buf & SDW_SCP_INT1_PORT0_3;
1581
1582                 /* To get port number corresponding to bits, shift it */
1583                 port = FIELD_GET(SDW_SCP_INT1_PORT0_3, port);
1584                 for_each_set_bit(bit, &port, 8) {
1585                         sdw_handle_port_interrupt(slave, bit,
1586                                                   &port_status[bit]);
1587                 }
1588
1589                 /* Check if cascade 2 interrupt is present */
1590                 if (buf & SDW_SCP_INT1_SCP2_CASCADE) {
1591                         port = buf2[0] & SDW_SCP_INTSTAT2_PORT4_10;
1592                         for_each_set_bit(bit, &port, 8) {
1593                                 /* scp2 ports start from 4 */
1594                                 port_num = bit + 3;
1595                                 sdw_handle_port_interrupt(slave,
1596                                                 port_num,
1597                                                 &port_status[port_num]);
1598                         }
1599                 }
1600
1601                 /* now check last cascade */
1602                 if (buf2[0] & SDW_SCP_INTSTAT2_SCP3_CASCADE) {
1603                         port = buf2[1] & SDW_SCP_INTSTAT3_PORT11_14;
1604                         for_each_set_bit(bit, &port, 8) {
1605                                 /* scp3 ports start from 11 */
1606                                 port_num = bit + 10;
1607                                 sdw_handle_port_interrupt(slave,
1608                                                 port_num,
1609                                                 &port_status[port_num]);
1610                         }
1611                 }
1612
1613                 /* Update the Slave driver */
1614                 if (slave_notify && slave->ops &&
1615                     slave->ops->interrupt_callback) {
1616                         slave_intr.sdca_cascade = sdca_cascade;
1617                         slave_intr.control_port = clear;
1618                         memcpy(slave_intr.port, &port_status,
1619                                sizeof(slave_intr.port));
1620
1621                         slave->ops->interrupt_callback(slave, &slave_intr);
1622                 }
1623
1624                 /* Ack interrupt */
1625                 ret = sdw_write_no_pm(slave, SDW_SCP_INT1, clear);
1626                 if (ret < 0) {
1627                         dev_err(&slave->dev,
1628                                 "SDW_SCP_INT1 write failed:%d\n", ret);
1629                         goto io_err;
1630                 }
1631
1632                 /* at this point all initial interrupt sources were handled */
1633                 slave->first_interrupt_done = true;
1634
1635                 /*
1636                  * Read status again to ensure no new interrupts arrived
1637                  * while servicing interrupts.
1638                  */
1639                 ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1640                 if (ret < 0) {
1641                         dev_err(&slave->dev,
1642                                 "SDW_SCP_INT1 recheck read failed:%d\n", ret);
1643                         goto io_err;
1644                 }
1645                 _buf = ret;
1646
1647                 ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, _buf2);
1648                 if (ret < 0) {
1649                         dev_err(&slave->dev,
1650                                 "SDW_SCP_INT2/3 recheck read failed:%d\n", ret);
1651                         goto io_err;
1652                 }
1653
1654                 if (slave->prop.is_sdca) {
1655                         ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1656                         if (ret < 0) {
1657                                 dev_err(&slave->dev,
1658                                         "SDW_DP0_INT recheck read failed:%d\n", ret);
1659                                 goto io_err;
1660                         }
1661                         sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1662                 }
1663
1664                 /*
1665                  * Make sure no interrupts are pending, but filter to limit loop
1666                  * to interrupts identified in the first status read
1667                  */
1668                 buf &= _buf;
1669                 buf2[0] &= _buf2[0];
1670                 buf2[1] &= _buf2[1];
1671                 stat = buf || buf2[0] || buf2[1] || sdca_cascade;
1672
1673                 /*
1674                  * Exit loop if Slave is continuously in ALERT state even
1675                  * after servicing the interrupt multiple times.
1676                  */
1677                 count++;
1678
1679                 /* we can get alerts while processing so keep retrying */
1680         } while (stat != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
1681
1682         if (count == SDW_READ_INTR_CLEAR_RETRY)
1683                 dev_warn(&slave->dev, "Reached MAX_RETRY on alert read\n");
1684
1685 io_err:
1686         pm_runtime_mark_last_busy(&slave->dev);
1687         pm_runtime_put_autosuspend(&slave->dev);
1688
1689         return ret;
1690 }
1691
1692 static int sdw_update_slave_status(struct sdw_slave *slave,
1693                                    enum sdw_slave_status status)
1694 {
1695         unsigned long time;
1696
1697         if (!slave->probed) {
1698                 /*
1699                  * the slave status update is typically handled in an
1700                  * interrupt thread, which can race with the driver
1701                  * probe, e.g. when a module needs to be loaded.
1702                  *
1703                  * make sure the probe is complete before updating
1704                  * status.
1705                  */
1706                 time = wait_for_completion_timeout(&slave->probe_complete,
1707                                 msecs_to_jiffies(DEFAULT_PROBE_TIMEOUT));
1708                 if (!time) {
1709                         dev_err(&slave->dev, "Probe not complete, timed out\n");
1710                         return -ETIMEDOUT;
1711                 }
1712         }
1713
1714         if (!slave->ops || !slave->ops->update_status)
1715                 return 0;
1716
1717         return slave->ops->update_status(slave, status);
1718 }
1719
1720 /**
1721  * sdw_handle_slave_status() - Handle Slave status
1722  * @bus: SDW bus instance
1723  * @status: Status for all Slave(s)
1724  */
1725 int sdw_handle_slave_status(struct sdw_bus *bus,
1726                             enum sdw_slave_status status[])
1727 {
1728         enum sdw_slave_status prev_status;
1729         struct sdw_slave *slave;
1730         bool attached_initializing;
1731         int i, ret = 0;
1732
1733         /* first check if any Slaves fell off the bus */
1734         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1735                 mutex_lock(&bus->bus_lock);
1736                 if (test_bit(i, bus->assigned) == false) {
1737                         mutex_unlock(&bus->bus_lock);
1738                         continue;
1739                 }
1740                 mutex_unlock(&bus->bus_lock);
1741
1742                 slave = sdw_get_slave(bus, i);
1743                 if (!slave)
1744                         continue;
1745
1746                 if (status[i] == SDW_SLAVE_UNATTACHED &&
1747                     slave->status != SDW_SLAVE_UNATTACHED) {
1748                         dev_warn(&slave->dev, "Slave %d state check1: UNATTACHED, status was %d\n",
1749                                  i, slave->status);
1750                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1751                 }
1752         }
1753
1754         if (status[0] == SDW_SLAVE_ATTACHED) {
1755                 dev_dbg(bus->dev, "Slave attached, programming device number\n");
1756                 ret = sdw_program_device_num(bus);
1757                 if (ret < 0)
1758                         dev_err(bus->dev, "Slave attach failed: %d\n", ret);
1759                 /*
1760                  * programming a device number will have side effects,
1761                  * so we deal with other devices at a later time
1762                  */
1763                 return ret;
1764         }
1765
1766         /* Continue to check other slave statuses */
1767         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1768                 mutex_lock(&bus->bus_lock);
1769                 if (test_bit(i, bus->assigned) == false) {
1770                         mutex_unlock(&bus->bus_lock);
1771                         continue;
1772                 }
1773                 mutex_unlock(&bus->bus_lock);
1774
1775                 slave = sdw_get_slave(bus, i);
1776                 if (!slave)
1777                         continue;
1778
1779                 attached_initializing = false;
1780
1781                 switch (status[i]) {
1782                 case SDW_SLAVE_UNATTACHED:
1783                         if (slave->status == SDW_SLAVE_UNATTACHED)
1784                                 break;
1785
1786                         dev_warn(&slave->dev, "Slave %d state check2: UNATTACHED, status was %d\n",
1787                                  i, slave->status);
1788
1789                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1790                         break;
1791
1792                 case SDW_SLAVE_ALERT:
1793                         ret = sdw_handle_slave_alerts(slave);
1794                         if (ret < 0)
1795                                 dev_err(&slave->dev,
1796                                         "Slave %d alert handling failed: %d\n",
1797                                         i, ret);
1798                         break;
1799
1800                 case SDW_SLAVE_ATTACHED:
1801                         if (slave->status == SDW_SLAVE_ATTACHED)
1802                                 break;
1803
1804                         prev_status = slave->status;
1805                         sdw_modify_slave_status(slave, SDW_SLAVE_ATTACHED);
1806
1807                         if (prev_status == SDW_SLAVE_ALERT)
1808                                 break;
1809
1810                         attached_initializing = true;
1811
1812                         ret = sdw_initialize_slave(slave);
1813                         if (ret < 0)
1814                                 dev_err(&slave->dev,
1815                                         "Slave %d initialization failed: %d\n",
1816                                         i, ret);
1817
1818                         break;
1819
1820                 default:
1821                         dev_err(&slave->dev, "Invalid slave %d status:%d\n",
1822                                 i, status[i]);
1823                         break;
1824                 }
1825
1826                 ret = sdw_update_slave_status(slave, status[i]);
1827                 if (ret < 0)
1828                         dev_err(&slave->dev,
1829                                 "Update Slave status failed:%d\n", ret);
1830                 if (attached_initializing) {
1831                         dev_dbg(&slave->dev,
1832                                 "%s: signaling initialization completion for Slave %d\n",
1833                                 __func__, slave->dev_num);
1834
1835                         complete(&slave->initialization_complete);
1836
1837                         /*
1838                          * If the manager became pm_runtime active, the peripherals will be
1839                          * restarted and attach, but their pm_runtime status may remain
1840                          * suspended. If the 'update_slave_status' callback initiates
1841                          * any sort of deferred processing, this processing would not be
1842                          * cancelled on pm_runtime suspend.
1843                          * To avoid such zombie states, we queue a request to resume.
1844                          * This would be a no-op in case the peripheral was being resumed
1845                          * by e.g. the ALSA/ASoC framework.
1846                          */
1847                         pm_request_resume(&slave->dev);
1848                 }
1849         }
1850
1851         return ret;
1852 }
1853 EXPORT_SYMBOL(sdw_handle_slave_status);
1854
1855 void sdw_clear_slave_status(struct sdw_bus *bus, u32 request)
1856 {
1857         struct sdw_slave *slave;
1858         int i;
1859
1860         /* Check all non-zero devices */
1861         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1862                 mutex_lock(&bus->bus_lock);
1863                 if (test_bit(i, bus->assigned) == false) {
1864                         mutex_unlock(&bus->bus_lock);
1865                         continue;
1866                 }
1867                 mutex_unlock(&bus->bus_lock);
1868
1869                 slave = sdw_get_slave(bus, i);
1870                 if (!slave)
1871                         continue;
1872
1873                 if (slave->status != SDW_SLAVE_UNATTACHED) {
1874                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1875                         slave->first_interrupt_done = false;
1876                         sdw_update_slave_status(slave, SDW_SLAVE_UNATTACHED);
1877                 }
1878
1879                 /* keep track of request, used in pm_runtime resume */
1880                 slave->unattach_request = request;
1881         }
1882 }
1883 EXPORT_SYMBOL(sdw_clear_slave_status);