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