drivers/soundwire/bus.c

   1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
   2 // Copyright(c) 2015-17 Intel Corporation.
   3
   4 #include <linux/acpi.h>
   5 #include <linux/delay.h>
   6 #include <linux/mod_devicetable.h>
   7 #include <linux/pm_runtime.h>
   8 #include <linux/soundwire/sdw_registers.h>
   9 #include <linux/soundwire/sdw.h>
  10 #include <linux/soundwire/sdw_type.h>
  11 #include "bus.h"
  12 #include "sysfs_local.h"
  13
  14 static DEFINE_IDA(sdw_bus_ida);
  15 static DEFINE_IDA(sdw_peripheral_ida);
  16
  17 static int sdw_get_id(struct sdw_bus *bus)
  18 {
  19         int rc = ida_alloc(&sdw_bus_ida, GFP_KERNEL);
  20
  21         if (rc < 0)
  22                 return rc;
  23
  24         bus->id = rc;
  25         return 0;
  26 }
  27
  28 /**
  29  * sdw_bus_master_add() - add a bus Master instance
  30  * @bus: bus instance
  31  * @parent: parent device
  32  * @fwnode: firmware node handle
  33  *
  34  * Initializes the bus instance, read properties and create child
  35  * devices.
  36  */
  37 int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent,
  38                        struct fwnode_handle *fwnode)
  39 {
  40         struct sdw_master_prop *prop = NULL;
  41         int ret;
  42
  43         if (!parent) {
  44                 pr_err("SoundWire parent device is not set\n");
  45                 return -ENODEV;
  46         }
  47
  48         ret = sdw_get_id(bus);
  49         if (ret < 0) {
  50                 dev_err(parent, "Failed to get bus id\n");
  51                 return ret;
  52         }
  53
  54         ret = sdw_master_device_add(bus, parent, fwnode);
  55         if (ret < 0) {
  56                 dev_err(parent, "Failed to add master device at link %d\n",
  57                         bus->link_id);
  58                 return ret;
  59         }
  60
  61         if (!bus->ops) {
  62                 dev_err(bus->dev, "SoundWire Bus ops are not set\n");
  63                 return -EINVAL;
  64         }
  65
  66         if (!bus->compute_params) {
  67                 dev_err(bus->dev,
  68                         "Bandwidth allocation not configured, compute_params no set\n");
  69                 return -EINVAL;
  70         }
  71
  72         mutex_init(&bus->msg_lock);
  73         mutex_init(&bus->bus_lock);
  74         INIT_LIST_HEAD(&bus->slaves);
  75         INIT_LIST_HEAD(&bus->m_rt_list);
  76
  77         /*
  78          * Initialize multi_link flag
  79          */
  80         bus->multi_link = false;
  81         if (bus->ops->read_prop) {
  82                 ret = bus->ops->read_prop(bus);
  83                 if (ret < 0) {
  84                         dev_err(bus->dev,
  85                                 "Bus read properties failed:%d\n", ret);
  86                         return ret;
  87                 }
  88         }
  89
  90         sdw_bus_debugfs_init(bus);
  91
  92         /*
  93          * Device numbers in SoundWire are 0 through 15. Enumeration device
  94          * number (0), Broadcast device number (15), Group numbers (12 and
  95          * 13) and Master device number (14) are not used for assignment so
  96          * mask these and other higher bits.
  97          */
  98
  99         /* Set higher order bits */
 100         *bus->assigned = ~GENMASK(SDW_BROADCAST_DEV_NUM, SDW_ENUM_DEV_NUM);
 101
 102         /* Set enumuration device number and broadcast device number */
 103         set_bit(SDW_ENUM_DEV_NUM, bus->assigned);
 104         set_bit(SDW_BROADCAST_DEV_NUM, bus->assigned);
 105
 106         /* Set group device numbers and master device number */
 107         set_bit(SDW_GROUP12_DEV_NUM, bus->assigned);
 108         set_bit(SDW_GROUP13_DEV_NUM, bus->assigned);
 109         set_bit(SDW_MASTER_DEV_NUM, bus->assigned);
 110
 111         /*
 112          * SDW is an enumerable bus, but devices can be powered off. So,
 113          * they won't be able to report as present.
 114          *
 115          * Create Slave devices based on Slaves described in
 116          * the respective firmware (ACPI/DT)
 117          */
 118         if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev))
 119                 ret = sdw_acpi_find_slaves(bus);
 120         else if (IS_ENABLED(CONFIG_OF) && bus->dev->of_node)
 121                 ret = sdw_of_find_slaves(bus);
 122         else
 123                 ret = -ENOTSUPP; /* No ACPI/DT so error out */
 124
 125         if (ret < 0) {
 126                 dev_err(bus->dev, "Finding slaves failed:%d\n", ret);
 127                 return ret;
 128         }
 129
 130         /*
 131          * Initialize clock values based on Master properties. The max
 132          * frequency is read from max_clk_freq property. Current assumption
 133          * is that the bus will start at highest clock frequency when
 134          * powered on.
 135          *
 136          * Default active bank will be 0 as out of reset the Slaves have
 137          * to start with bank 0 (Table 40 of Spec)
 138          */
 139         prop = &bus->prop;
 140         bus->params.max_dr_freq = prop->max_clk_freq * SDW_DOUBLE_RATE_FACTOR;
 141         bus->params.curr_dr_freq = bus->params.max_dr_freq;
 142         bus->params.curr_bank = SDW_BANK0;
 143         bus->params.next_bank = SDW_BANK1;
 144
 145         return 0;
 146 }
 147 EXPORT_SYMBOL(sdw_bus_master_add);
 148
 149 static int sdw_delete_slave(struct device *dev, void *data)
 150 {
 151         struct sdw_slave *slave = dev_to_sdw_dev(dev);
 152         struct sdw_bus *bus = slave->bus;
 153
 154         pm_runtime_disable(dev);
 155
 156         sdw_slave_debugfs_exit(slave);
 157
 158         mutex_lock(&bus->bus_lock);
 159
 160         if (slave->dev_num) { /* clear dev_num if assigned */
 161                 clear_bit(slave->dev_num, bus->assigned);
 162                 if (bus->dev_num_ida_min)
 163                         ida_free(&sdw_peripheral_ida, slave->dev_num);
 164         }
 165         list_del_init(&slave->node);
 166         mutex_unlock(&bus->bus_lock);
 167
 168         device_unregister(dev);
 169         return 0;
 170 }
 171
 172 /**
 173  * sdw_bus_master_delete() - delete the bus master instance
 174  * @bus: bus to be deleted
 175  *
 176  * Remove the instance, delete the child devices.
 177  */
 178 void sdw_bus_master_delete(struct sdw_bus *bus)
 179 {
 180         device_for_each_child(bus->dev, NULL, sdw_delete_slave);
 181         sdw_master_device_del(bus);
 182
 183         sdw_bus_debugfs_exit(bus);
 184         ida_free(&sdw_bus_ida, bus->id);
 185 }
 186 EXPORT_SYMBOL(sdw_bus_master_delete);
 187
 188 /*
 189  * SDW IO Calls
 190  */
 191
 192 static inline int find_response_code(enum sdw_command_response resp)
 193 {
 194         switch (resp) {
 195         case SDW_CMD_OK:
 196                 return 0;
 197
 198         case SDW_CMD_IGNORED:
 199                 return -ENODATA;
 200
 201         case SDW_CMD_TIMEOUT:
 202                 return -ETIMEDOUT;
 203
 204         default:
 205                 return -EIO;
 206         }
 207 }
 208
 209 static inline int do_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 210 {
 211         int retry = bus->prop.err_threshold;
 212         enum sdw_command_response resp;
 213         int ret = 0, i;
 214
 215         for (i = 0; i <= retry; i++) {
 216                 resp = bus->ops->xfer_msg(bus, msg);
 217                 ret = find_response_code(resp);
 218
 219                 /* if cmd is ok or ignored return */
 220                 if (ret == 0 || ret == -ENODATA)
 221                         return ret;
 222         }
 223
 224         return ret;
 225 }
 226
 227 static inline int do_transfer_defer(struct sdw_bus *bus,
 228                                     struct sdw_msg *msg)
 229 {
 230         struct sdw_defer *defer = &bus->defer_msg;
 231         int retry = bus->prop.err_threshold;
 232         enum sdw_command_response resp;
 233         int ret = 0, i;
 234
 235         defer->msg = msg;
 236         defer->length = msg->len;
 237         init_completion(&defer->complete);
 238
 239         for (i = 0; i <= retry; i++) {
 240                 resp = bus->ops->xfer_msg_defer(bus);
 241                 ret = find_response_code(resp);
 242                 /* if cmd is ok or ignored return */
 243                 if (ret == 0 || ret == -ENODATA)
 244                         return ret;
 245         }
 246
 247         return ret;
 248 }
 249
 250 static int sdw_transfer_unlocked(struct sdw_bus *bus, struct sdw_msg *msg)
 251 {
 252         int ret;
 253
 254         ret = do_transfer(bus, msg);
 255         if (ret != 0 && ret != -ENODATA)
 256                 dev_err(bus->dev, "trf on Slave %d failed:%d %s addr %x count %d\n",
 257                         msg->dev_num, ret,
 258                         (msg->flags & SDW_MSG_FLAG_WRITE) ? "write" : "read",
 259                         msg->addr, msg->len);
 260
 261         return ret;
 262 }
 263
 264 /**
 265  * sdw_transfer() - Synchronous transfer message to a SDW Slave device
 266  * @bus: SDW bus
 267  * @msg: SDW message to be xfered
 268  */
 269 int sdw_transfer(struct sdw_bus *bus, struct sdw_msg *msg)
 270 {
 271         int ret;
 272
 273         mutex_lock(&bus->msg_lock);
 274
 275         ret = sdw_transfer_unlocked(bus, msg);
 276
 277         mutex_unlock(&bus->msg_lock);
 278
 279         return ret;
 280 }
 281
 282 /**
 283  * sdw_show_ping_status() - Direct report of PING status, to be used by Peripheral drivers
 284  * @bus: SDW bus
 285  * @sync_delay: Delay before reading status
 286  */
 287 void sdw_show_ping_status(struct sdw_bus *bus, bool sync_delay)
 288 {
 289         u32 status;
 290
 291         if (!bus->ops->read_ping_status)
 292                 return;
 293
 294         /*
 295          * wait for peripheral to sync if desired. 10-15ms should be more than
 296          * enough in most cases.
 297          */
 298         if (sync_delay)
 299                 usleep_range(10000, 15000);
 300
 301         mutex_lock(&bus->msg_lock);
 302
 303         status = bus->ops->read_ping_status(bus);
 304
 305         mutex_unlock(&bus->msg_lock);
 306
 307         if (!status)
 308                 dev_warn(bus->dev, "%s: no peripherals attached\n", __func__);
 309         else
 310                 dev_dbg(bus->dev, "PING status: %#x\n", status);
 311 }
 312 EXPORT_SYMBOL(sdw_show_ping_status);
 313
 314 /**
 315  * sdw_transfer_defer() - Asynchronously transfer message to a SDW Slave device
 316  * @bus: SDW bus
 317  * @msg: SDW message to be xfered
 318  *
 319  * Caller needs to hold the msg_lock lock while calling this
 320  */
 321 int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg)
 322 {
 323         int ret;
 324
 325         if (!bus->ops->xfer_msg_defer)
 326                 return -ENOTSUPP;
 327
 328         ret = do_transfer_defer(bus, msg);
 329         if (ret != 0 && ret != -ENODATA)
 330                 dev_err(bus->dev, "Defer trf on Slave %d failed:%d\n",
 331                         msg->dev_num, ret);
 332
 333         return ret;
 334 }
 335
 336 int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave,
 337                  u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf)
 338 {
 339         memset(msg, 0, sizeof(*msg));
 340         msg->addr = addr; /* addr is 16 bit and truncated here */
 341         msg->len = count;
 342         msg->dev_num = dev_num;
 343         msg->flags = flags;
 344         msg->buf = buf;
 345
 346         if (addr < SDW_REG_NO_PAGE) /* no paging area */
 347                 return 0;
 348
 349         if (addr >= SDW_REG_MAX) { /* illegal addr */
 350                 pr_err("SDW: Invalid address %x passed\n", addr);
 351                 return -EINVAL;
 352         }
 353
 354         if (addr < SDW_REG_OPTIONAL_PAGE) { /* 32k but no page */
 355                 if (slave && !slave->prop.paging_support)
 356                         return 0;
 357                 /* no need for else as that will fall-through to paging */
 358         }
 359
 360         /* paging mandatory */
 361         if (dev_num == SDW_ENUM_DEV_NUM || dev_num == SDW_BROADCAST_DEV_NUM) {
 362                 pr_err("SDW: Invalid device for paging :%d\n", dev_num);
 363                 return -EINVAL;
 364         }
 365
 366         if (!slave) {
 367                 pr_err("SDW: No slave for paging addr\n");
 368                 return -EINVAL;
 369         }
 370
 371         if (!slave->prop.paging_support) {
 372                 dev_err(&slave->dev,
 373                         "address %x needs paging but no support\n", addr);
 374                 return -EINVAL;
 375         }
 376
 377         msg->addr_page1 = FIELD_GET(SDW_SCP_ADDRPAGE1_MASK, addr);
 378         msg->addr_page2 = FIELD_GET(SDW_SCP_ADDRPAGE2_MASK, addr);
 379         msg->addr |= BIT(15);
 380         msg->page = true;
 381
 382         return 0;
 383 }
 384
 385 /*
 386  * Read/Write IO functions.
 387  */
 388
 389 /**
 390  * sdw_nread_no_pm() - Read "n" contiguous SDW Slave registers with no PM
 391  * @slave: SDW Slave
 392  * @addr: Register address
 393  * @count: length
 394  * @val: Buffer for values to be read
 395  */
 396 int sdw_nread_no_pm(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 397 {
 398         struct sdw_msg msg;
 399         int ret;
 400
 401         ret = sdw_fill_msg(&msg, slave, addr, count,
 402                            slave->dev_num, SDW_MSG_FLAG_READ, val);
 403         if (ret < 0)
 404                 return ret;
 405
 406         ret = sdw_transfer(slave->bus, &msg);
 407         if (slave->is_mockup_device)
 408                 ret = 0;
 409         return ret;
 410 }
 411 EXPORT_SYMBOL(sdw_nread_no_pm);
 412
 413 /**
 414  * sdw_nwrite_no_pm() - Write "n" contiguous SDW Slave registers with no PM
 415  * @slave: SDW Slave
 416  * @addr: Register address
 417  * @count: length
 418  * @val: Buffer for values to be written
 419  */
 420 int sdw_nwrite_no_pm(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 421 {
 422         struct sdw_msg msg;
 423         int ret;
 424
 425         ret = sdw_fill_msg(&msg, slave, addr, count,
 426                            slave->dev_num, SDW_MSG_FLAG_WRITE, (u8 *)val);
 427         if (ret < 0)
 428                 return ret;
 429
 430         ret = sdw_transfer(slave->bus, &msg);
 431         if (slave->is_mockup_device)
 432                 ret = 0;
 433         return ret;
 434 }
 435 EXPORT_SYMBOL(sdw_nwrite_no_pm);
 436
 437 /**
 438  * sdw_write_no_pm() - Write a SDW Slave register with no PM
 439  * @slave: SDW Slave
 440  * @addr: Register address
 441  * @value: Register value
 442  */
 443 int sdw_write_no_pm(struct sdw_slave *slave, u32 addr, u8 value)
 444 {
 445         return sdw_nwrite_no_pm(slave, addr, 1, &value);
 446 }
 447 EXPORT_SYMBOL(sdw_write_no_pm);
 448
 449 static int
 450 sdw_bread_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr)
 451 {
 452         struct sdw_msg msg;
 453         u8 buf;
 454         int ret;
 455
 456         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 457                            SDW_MSG_FLAG_READ, &buf);
 458         if (ret < 0)
 459                 return ret;
 460
 461         ret = sdw_transfer(bus, &msg);
 462         if (ret < 0)
 463                 return ret;
 464
 465         return buf;
 466 }
 467
 468 static int
 469 sdw_bwrite_no_pm(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 470 {
 471         struct sdw_msg msg;
 472         int ret;
 473
 474         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 475                            SDW_MSG_FLAG_WRITE, &value);
 476         if (ret < 0)
 477                 return ret;
 478
 479         return sdw_transfer(bus, &msg);
 480 }
 481
 482 int sdw_bread_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr)
 483 {
 484         struct sdw_msg msg;
 485         u8 buf;
 486         int ret;
 487
 488         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 489                            SDW_MSG_FLAG_READ, &buf);
 490         if (ret < 0)
 491                 return ret;
 492
 493         ret = sdw_transfer_unlocked(bus, &msg);
 494         if (ret < 0)
 495                 return ret;
 496
 497         return buf;
 498 }
 499 EXPORT_SYMBOL(sdw_bread_no_pm_unlocked);
 500
 501 int sdw_bwrite_no_pm_unlocked(struct sdw_bus *bus, u16 dev_num, u32 addr, u8 value)
 502 {
 503         struct sdw_msg msg;
 504         int ret;
 505
 506         ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
 507                            SDW_MSG_FLAG_WRITE, &value);
 508         if (ret < 0)
 509                 return ret;
 510
 511         return sdw_transfer_unlocked(bus, &msg);
 512 }
 513 EXPORT_SYMBOL(sdw_bwrite_no_pm_unlocked);
 514
 515 /**
 516  * sdw_read_no_pm() - Read a SDW Slave register with no PM
 517  * @slave: SDW Slave
 518  * @addr: Register address
 519  */
 520 int sdw_read_no_pm(struct sdw_slave *slave, u32 addr)
 521 {
 522         u8 buf;
 523         int ret;
 524
 525         ret = sdw_nread_no_pm(slave, addr, 1, &buf);
 526         if (ret < 0)
 527                 return ret;
 528         else
 529                 return buf;
 530 }
 531 EXPORT_SYMBOL(sdw_read_no_pm);
 532
 533 int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 534 {
 535         int tmp;
 536
 537         tmp = sdw_read_no_pm(slave, addr);
 538         if (tmp < 0)
 539                 return tmp;
 540
 541         tmp = (tmp & ~mask) | val;
 542         return sdw_write_no_pm(slave, addr, tmp);
 543 }
 544 EXPORT_SYMBOL(sdw_update_no_pm);
 545
 546 /* Read-Modify-Write Slave register */
 547 int sdw_update(struct sdw_slave *slave, u32 addr, u8 mask, u8 val)
 548 {
 549         int tmp;
 550
 551         tmp = sdw_read(slave, addr);
 552         if (tmp < 0)
 553                 return tmp;
 554
 555         tmp = (tmp & ~mask) | val;
 556         return sdw_write(slave, addr, tmp);
 557 }
 558 EXPORT_SYMBOL(sdw_update);
 559
 560 /**
 561  * sdw_nread() - Read "n" contiguous SDW Slave registers
 562  * @slave: SDW Slave
 563  * @addr: Register address
 564  * @count: length
 565  * @val: Buffer for values to be read
 566  *
 567  * This version of the function will take a PM reference to the slave
 568  * device.
 569  */
 570 int sdw_nread(struct sdw_slave *slave, u32 addr, size_t count, u8 *val)
 571 {
 572         int ret;
 573
 574         ret = pm_runtime_resume_and_get(&slave->dev);
 575         if (ret < 0 && ret != -EACCES)
 576                 return ret;
 577
 578         ret = sdw_nread_no_pm(slave, addr, count, val);
 579
 580         pm_runtime_mark_last_busy(&slave->dev);
 581         pm_runtime_put(&slave->dev);
 582
 583         return ret;
 584 }
 585 EXPORT_SYMBOL(sdw_nread);
 586
 587 /**
 588  * sdw_nwrite() - Write "n" contiguous SDW Slave registers
 589  * @slave: SDW Slave
 590  * @addr: Register address
 591  * @count: length
 592  * @val: Buffer for values to be written
 593  *
 594  * This version of the function will take a PM reference to the slave
 595  * device.
 596  */
 597 int sdw_nwrite(struct sdw_slave *slave, u32 addr, size_t count, const u8 *val)
 598 {
 599         int ret;
 600
 601         ret = pm_runtime_resume_and_get(&slave->dev);
 602         if (ret < 0 && ret != -EACCES)
 603                 return ret;
 604
 605         ret = sdw_nwrite_no_pm(slave, addr, count, val);
 606
 607         pm_runtime_mark_last_busy(&slave->dev);
 608         pm_runtime_put(&slave->dev);
 609
 610         return ret;
 611 }
 612 EXPORT_SYMBOL(sdw_nwrite);
 613
 614 /**
 615  * sdw_read() - Read a SDW Slave register
 616  * @slave: SDW Slave
 617  * @addr: Register address
 618  *
 619  * This version of the function will take a PM reference to the slave
 620  * device.
 621  */
 622 int sdw_read(struct sdw_slave *slave, u32 addr)
 623 {
 624         u8 buf;
 625         int ret;
 626
 627         ret = sdw_nread(slave, addr, 1, &buf);
 628         if (ret < 0)
 629                 return ret;
 630
 631         return buf;
 632 }
 633 EXPORT_SYMBOL(sdw_read);
 634
 635 /**
 636  * sdw_write() - Write a SDW Slave register
 637  * @slave: SDW Slave
 638  * @addr: Register address
 639  * @value: Register value
 640  *
 641  * This version of the function will take a PM reference to the slave
 642  * device.
 643  */
 644 int sdw_write(struct sdw_slave *slave, u32 addr, u8 value)
 645 {
 646         return sdw_nwrite(slave, addr, 1, &value);
 647 }
 648 EXPORT_SYMBOL(sdw_write);
 649
 650 /*
 651  * SDW alert handling
 652  */
 653
 654 /* called with bus_lock held */
 655 static struct sdw_slave *sdw_get_slave(struct sdw_bus *bus, int i)
 656 {
 657         struct sdw_slave *slave;
 658
 659         list_for_each_entry(slave, &bus->slaves, node) {
 660                 if (slave->dev_num == i)
 661                         return slave;
 662         }
 663
 664         return NULL;
 665 }
 666
 667 int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id)
 668 {
 669         if (slave->id.mfg_id != id.mfg_id ||
 670             slave->id.part_id != id.part_id ||
 671             slave->id.class_id != id.class_id ||
 672             (slave->id.unique_id != SDW_IGNORED_UNIQUE_ID &&
 673              slave->id.unique_id != id.unique_id))
 674                 return -ENODEV;
 675
 676         return 0;
 677 }
 678 EXPORT_SYMBOL(sdw_compare_devid);
 679
 680 /* called with bus_lock held */
 681 static int sdw_get_device_num(struct sdw_slave *slave)
 682 {
 683         int bit;
 684
 685         if (slave->bus->dev_num_ida_min) {
 686                 bit = ida_alloc_range(&sdw_peripheral_ida,
 687                                       slave->bus->dev_num_ida_min, SDW_MAX_DEVICES,
 688                                       GFP_KERNEL);
 689                 if (bit < 0)
 690                         goto err;
 691         } else {
 692                 bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES);
 693                 if (bit == SDW_MAX_DEVICES) {
 694                         bit = -ENODEV;
 695                         goto err;
 696                 }
 697         }
 698
 699         /*
 700          * Do not update dev_num in Slave data structure here,
 701          * Update once program dev_num is successful
 702          */
 703         set_bit(bit, slave->bus->assigned);
 704
 705 err:
 706         return bit;
 707 }
 708
 709 static int sdw_assign_device_num(struct sdw_slave *slave)
 710 {
 711         struct sdw_bus *bus = slave->bus;
 712         int ret, dev_num;
 713         bool new_device = false;
 714
 715         /* check first if device number is assigned, if so reuse that */
 716         if (!slave->dev_num) {
 717                 if (!slave->dev_num_sticky) {
 718                         mutex_lock(&slave->bus->bus_lock);
 719                         dev_num = sdw_get_device_num(slave);
 720                         mutex_unlock(&slave->bus->bus_lock);
 721                         if (dev_num < 0) {
 722                                 dev_err(bus->dev, "Get dev_num failed: %d\n",
 723                                         dev_num);
 724                                 return dev_num;
 725                         }
 726                         slave->dev_num = dev_num;
 727                         slave->dev_num_sticky = dev_num;
 728                         new_device = true;
 729                 } else {
 730                         slave->dev_num = slave->dev_num_sticky;
 731                 }
 732         }
 733
 734         if (!new_device)
 735                 dev_dbg(bus->dev,
 736                         "Slave already registered, reusing dev_num:%d\n",
 737                         slave->dev_num);
 738
 739         /* Clear the slave->dev_num to transfer message on device 0 */
 740         dev_num = slave->dev_num;
 741         slave->dev_num = 0;
 742
 743         ret = sdw_write_no_pm(slave, SDW_SCP_DEVNUMBER, dev_num);
 744         if (ret < 0) {
 745                 dev_err(bus->dev, "Program device_num %d failed: %d\n",
 746                         dev_num, ret);
 747                 return ret;
 748         }
 749
 750         /* After xfer of msg, restore dev_num */
 751         slave->dev_num = slave->dev_num_sticky;
 752
 753         return 0;
 754 }
 755
 756 void sdw_extract_slave_id(struct sdw_bus *bus,
 757                           u64 addr, struct sdw_slave_id *id)
 758 {
 759         dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr);
 760
 761         id->sdw_version = SDW_VERSION(addr);
 762         id->unique_id = SDW_UNIQUE_ID(addr);
 763         id->mfg_id = SDW_MFG_ID(addr);
 764         id->part_id = SDW_PART_ID(addr);
 765         id->class_id = SDW_CLASS_ID(addr);
 766
 767         dev_dbg(bus->dev,
 768                 "SDW Slave class_id 0x%02x, mfg_id 0x%04x, part_id 0x%04x, unique_id 0x%x, version 0x%x\n",
 769                 id->class_id, id->mfg_id, id->part_id, id->unique_id, id->sdw_version);
 770 }
 771 EXPORT_SYMBOL(sdw_extract_slave_id);
 772
 773 static int sdw_program_device_num(struct sdw_bus *bus, bool *programmed)
 774 {
 775         u8 buf[SDW_NUM_DEV_ID_REGISTERS] = {0};
 776         struct sdw_slave *slave, *_s;
 777         struct sdw_slave_id id;
 778         struct sdw_msg msg;
 779         bool found;
 780         int count = 0, ret;
 781         u64 addr;
 782
 783         *programmed = false;
 784
 785         /* No Slave, so use raw xfer api */
 786         ret = sdw_fill_msg(&msg, NULL, SDW_SCP_DEVID_0,
 787                            SDW_NUM_DEV_ID_REGISTERS, 0, SDW_MSG_FLAG_READ, buf);
 788         if (ret < 0)
 789                 return ret;
 790
 791         do {
 792                 ret = sdw_transfer(bus, &msg);
 793                 if (ret == -ENODATA) { /* end of device id reads */
 794                         dev_dbg(bus->dev, "No more devices to enumerate\n");
 795                         ret = 0;
 796                         break;
 797                 }
 798                 if (ret < 0) {
 799                         dev_err(bus->dev, "DEVID read fail:%d\n", ret);
 800                         break;
 801                 }
 802
 803                 /*
 804                  * Construct the addr and extract. Cast the higher shift
 805                  * bits to avoid truncation due to size limit.
 806                  */
 807                 addr = buf[5] | (buf[4] << 8) | (buf[3] << 16) |
 808                         ((u64)buf[2] << 24) | ((u64)buf[1] << 32) |
 809                         ((u64)buf[0] << 40);
 810
 811                 sdw_extract_slave_id(bus, addr, &id);
 812
 813                 found = false;
 814                 /* Now compare with entries */
 815                 list_for_each_entry_safe(slave, _s, &bus->slaves, node) {
 816                         if (sdw_compare_devid(slave, id) == 0) {
 817                                 found = true;
 818
 819                                 /*
 820                                  * To prevent skipping state-machine stages don't
 821                                  * program a device until we've seen it UNATTACH.
 822                                  * Must return here because no other device on #0
 823                                  * can be detected until this one has been
 824                                  * assigned a device ID.
 825                                  */
 826                                 if (slave->status != SDW_SLAVE_UNATTACHED)
 827                                         return 0;
 828
 829                                 /*
 830                                  * Assign a new dev_num to this Slave and
 831                                  * not mark it present. It will be marked
 832                                  * present after it reports ATTACHED on new
 833                                  * dev_num
 834                                  */
 835                                 ret = sdw_assign_device_num(slave);
 836                                 if (ret < 0) {
 837                                         dev_err(bus->dev,
 838                                                 "Assign dev_num failed:%d\n",
 839                                                 ret);
 840                                         return ret;
 841                                 }
 842
 843                                 *programmed = true;
 844
 845                                 break;
 846                         }
 847                 }
 848
 849                 if (!found) {
 850                         /* TODO: Park this device in Group 13 */
 851
 852                         /*
 853                          * add Slave device even if there is no platform
 854                          * firmware description. There will be no driver probe
 855                          * but the user/integration will be able to see the
 856                          * device, enumeration status and device number in sysfs
 857                          */
 858                         sdw_slave_add(bus, &id, NULL);
 859
 860                         dev_err(bus->dev, "Slave Entry not found\n");
 861                 }
 862
 863                 count++;
 864
 865                 /*
 866                  * Check till error out or retry (count) exhausts.
 867                  * Device can drop off and rejoin during enumeration
 868                  * so count till twice the bound.
 869                  */
 870
 871         } while (ret == 0 && count < (SDW_MAX_DEVICES * 2));
 872
 873         return ret;
 874 }
 875
 876 static void sdw_modify_slave_status(struct sdw_slave *slave,
 877                                     enum sdw_slave_status status)
 878 {
 879         struct sdw_bus *bus = slave->bus;
 880
 881         mutex_lock(&bus->bus_lock);
 882
 883         dev_vdbg(bus->dev,
 884                  "changing status slave %d status %d new status %d\n",
 885                  slave->dev_num, slave->status, status);
 886
 887         if (status == SDW_SLAVE_UNATTACHED) {
 888                 dev_dbg(&slave->dev,
 889                         "initializing enumeration and init completion for Slave %d\n",
 890                         slave->dev_num);
 891
 892                 init_completion(&slave->enumeration_complete);
 893                 init_completion(&slave->initialization_complete);
 894
 895         } else if ((status == SDW_SLAVE_ATTACHED) &&
 896                    (slave->status == SDW_SLAVE_UNATTACHED)) {
 897                 dev_dbg(&slave->dev,
 898                         "signaling enumeration completion for Slave %d\n",
 899                         slave->dev_num);
 900
 901                 complete(&slave->enumeration_complete);
 902         }
 903         slave->status = status;
 904         mutex_unlock(&bus->bus_lock);
 905 }
 906
 907 static int sdw_slave_clk_stop_callback(struct sdw_slave *slave,
 908                                        enum sdw_clk_stop_mode mode,
 909                                        enum sdw_clk_stop_type type)
 910 {
 911         int ret = 0;
 912
 913         mutex_lock(&slave->sdw_dev_lock);
 914
 915         if (slave->probed)  {
 916                 struct device *dev = &slave->dev;
 917                 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
 918
 919                 if (drv->ops && drv->ops->clk_stop)
 920                         ret = drv->ops->clk_stop(slave, mode, type);
 921         }
 922
 923         mutex_unlock(&slave->sdw_dev_lock);
 924
 925         return ret;
 926 }
 927
 928 static int sdw_slave_clk_stop_prepare(struct sdw_slave *slave,
 929                                       enum sdw_clk_stop_mode mode,
 930                                       bool prepare)
 931 {
 932         bool wake_en;
 933         u32 val = 0;
 934         int ret;
 935
 936         wake_en = slave->prop.wake_capable;
 937
 938         if (prepare) {
 939                 val = SDW_SCP_SYSTEMCTRL_CLK_STP_PREP;
 940
 941                 if (mode == SDW_CLK_STOP_MODE1)
 942                         val |= SDW_SCP_SYSTEMCTRL_CLK_STP_MODE1;
 943
 944                 if (wake_en)
 945                         val |= SDW_SCP_SYSTEMCTRL_WAKE_UP_EN;
 946         } else {
 947                 ret = sdw_read_no_pm(slave, SDW_SCP_SYSTEMCTRL);
 948                 if (ret < 0) {
 949                         if (ret != -ENODATA)
 950                                 dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL read failed:%d\n", ret);
 951                         return ret;
 952                 }
 953                 val = ret;
 954                 val &= ~(SDW_SCP_SYSTEMCTRL_CLK_STP_PREP);
 955         }
 956
 957         ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val);
 958
 959         if (ret < 0 && ret != -ENODATA)
 960                 dev_err(&slave->dev, "SDW_SCP_SYSTEMCTRL write failed:%d\n", ret);
 961
 962         return ret;
 963 }
 964
 965 static int sdw_bus_wait_for_clk_prep_deprep(struct sdw_bus *bus, u16 dev_num)
 966 {
 967         int retry = bus->clk_stop_timeout;
 968         int val;
 969
 970         do {
 971                 val = sdw_bread_no_pm(bus, dev_num, SDW_SCP_STAT);
 972                 if (val < 0) {
 973                         if (val != -ENODATA)
 974                                 dev_err(bus->dev, "SDW_SCP_STAT bread failed:%d\n", val);
 975                         return val;
 976                 }
 977                 val &= SDW_SCP_STAT_CLK_STP_NF;
 978                 if (!val) {
 979                         dev_dbg(bus->dev, "clock stop prep/de-prep done slave:%d\n",
 980                                 dev_num);
 981                         return 0;
 982                 }
 983
 984                 usleep_range(1000, 1500);
 985                 retry--;
 986         } while (retry);
 987
 988         dev_err(bus->dev, "clock stop prep/de-prep failed slave:%d\n",
 989                 dev_num);
 990
 991         return -ETIMEDOUT;
 992 }
 993
 994 /**
 995  * sdw_bus_prep_clk_stop: prepare Slave(s) for clock stop
 996  *
 997  * @bus: SDW bus instance
 998  *
 999  * Query Slave for clock stop mode and prepare for that mode.
1000  */
1001 int sdw_bus_prep_clk_stop(struct sdw_bus *bus)
1002 {
1003         bool simple_clk_stop = true;
1004         struct sdw_slave *slave;
1005         bool is_slave = false;
1006         int ret = 0;
1007
1008         /*
1009          * In order to save on transition time, prepare
1010          * each Slave and then wait for all Slave(s) to be
1011          * prepared for clock stop.
1012          * If one of the Slave devices has lost sync and
1013          * replies with Command Ignored/-ENODATA, we continue
1014          * the loop
1015          */
1016         list_for_each_entry(slave, &bus->slaves, node) {
1017                 if (!slave->dev_num)
1018                         continue;
1019
1020                 if (slave->status != SDW_SLAVE_ATTACHED &&
1021                     slave->status != SDW_SLAVE_ALERT)
1022                         continue;
1023
1024                 /* Identify if Slave(s) are available on Bus */
1025                 is_slave = true;
1026
1027                 ret = sdw_slave_clk_stop_callback(slave,
1028                                                   SDW_CLK_STOP_MODE0,
1029                                                   SDW_CLK_PRE_PREPARE);
1030                 if (ret < 0 && ret != -ENODATA) {
1031                         dev_err(&slave->dev, "clock stop pre-prepare cb failed:%d\n", ret);
1032                         return ret;
1033                 }
1034
1035                 /* Only prepare a Slave device if needed */
1036                 if (!slave->prop.simple_clk_stop_capable) {
1037                         simple_clk_stop = false;
1038
1039                         ret = sdw_slave_clk_stop_prepare(slave,
1040                                                          SDW_CLK_STOP_MODE0,
1041                                                          true);
1042                         if (ret < 0 && ret != -ENODATA) {
1043                                 dev_err(&slave->dev, "clock stop prepare failed:%d\n", ret);
1044                                 return ret;
1045                         }
1046                 }
1047         }
1048
1049         /* Skip remaining clock stop preparation if no Slave is attached */
1050         if (!is_slave)
1051                 return 0;
1052
1053         /*
1054          * Don't wait for all Slaves to be ready if they follow the simple
1055          * state machine
1056          */
1057         if (!simple_clk_stop) {
1058                 ret = sdw_bus_wait_for_clk_prep_deprep(bus,
1059                                                        SDW_BROADCAST_DEV_NUM);
1060                 /*
1061                  * if there are no Slave devices present and the reply is
1062                  * Command_Ignored/-ENODATA, we don't need to continue with the
1063                  * flow and can just return here. The error code is not modified
1064                  * and its handling left as an exercise for the caller.
1065                  */
1066                 if (ret < 0)
1067                         return ret;
1068         }
1069
1070         /* Inform slaves that prep is done */
1071         list_for_each_entry(slave, &bus->slaves, node) {
1072                 if (!slave->dev_num)
1073                         continue;
1074
1075                 if (slave->status != SDW_SLAVE_ATTACHED &&
1076                     slave->status != SDW_SLAVE_ALERT)
1077                         continue;
1078
1079                 ret = sdw_slave_clk_stop_callback(slave,
1080                                                   SDW_CLK_STOP_MODE0,
1081                                                   SDW_CLK_POST_PREPARE);
1082
1083                 if (ret < 0 && ret != -ENODATA) {
1084                         dev_err(&slave->dev, "clock stop post-prepare cb failed:%d\n", ret);
1085                         return ret;
1086                 }
1087         }
1088
1089         return 0;
1090 }
1091 EXPORT_SYMBOL(sdw_bus_prep_clk_stop);
1092
1093 /**
1094  * sdw_bus_clk_stop: stop bus clock
1095  *
1096  * @bus: SDW bus instance
1097  *
1098  * After preparing the Slaves for clock stop, stop the clock by broadcasting
1099  * write to SCP_CTRL register.
1100  */
1101 int sdw_bus_clk_stop(struct sdw_bus *bus)
1102 {
1103         int ret;
1104
1105         /*
1106          * broadcast clock stop now, attached Slaves will ACK this,
1107          * unattached will ignore
1108          */
1109         ret = sdw_bwrite_no_pm(bus, SDW_BROADCAST_DEV_NUM,
1110                                SDW_SCP_CTRL, SDW_SCP_CTRL_CLK_STP_NOW);
1111         if (ret < 0) {
1112                 if (ret != -ENODATA)
1113                         dev_err(bus->dev, "ClockStopNow Broadcast msg failed %d\n", ret);
1114                 return ret;
1115         }
1116
1117         return 0;
1118 }
1119 EXPORT_SYMBOL(sdw_bus_clk_stop);
1120
1121 /**
1122  * sdw_bus_exit_clk_stop: Exit clock stop mode
1123  *
1124  * @bus: SDW bus instance
1125  *
1126  * This De-prepares the Slaves by exiting Clock Stop Mode 0. For the Slaves
1127  * exiting Clock Stop Mode 1, they will be de-prepared after they enumerate
1128  * back.
1129  */
1130 int sdw_bus_exit_clk_stop(struct sdw_bus *bus)
1131 {
1132         bool simple_clk_stop = true;
1133         struct sdw_slave *slave;
1134         bool is_slave = false;
1135         int ret;
1136
1137         /*
1138          * In order to save on transition time, de-prepare
1139          * each Slave and then wait for all Slave(s) to be
1140          * de-prepared after clock resume.
1141          */
1142         list_for_each_entry(slave, &bus->slaves, node) {
1143                 if (!slave->dev_num)
1144                         continue;
1145
1146                 if (slave->status != SDW_SLAVE_ATTACHED &&
1147                     slave->status != SDW_SLAVE_ALERT)
1148                         continue;
1149
1150                 /* Identify if Slave(s) are available on Bus */
1151                 is_slave = true;
1152
1153                 ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1154                                                   SDW_CLK_PRE_DEPREPARE);
1155                 if (ret < 0)
1156                         dev_warn(&slave->dev, "clock stop pre-deprepare cb failed:%d\n", ret);
1157
1158                 /* Only de-prepare a Slave device if needed */
1159                 if (!slave->prop.simple_clk_stop_capable) {
1160                         simple_clk_stop = false;
1161
1162                         ret = sdw_slave_clk_stop_prepare(slave, SDW_CLK_STOP_MODE0,
1163                                                          false);
1164
1165                         if (ret < 0)
1166                                 dev_warn(&slave->dev, "clock stop deprepare failed:%d\n", ret);
1167                 }
1168         }
1169
1170         /* Skip remaining clock stop de-preparation if no Slave is attached */
1171         if (!is_slave)
1172                 return 0;
1173
1174         /*
1175          * Don't wait for all Slaves to be ready if they follow the simple
1176          * state machine
1177          */
1178         if (!simple_clk_stop) {
1179                 ret = sdw_bus_wait_for_clk_prep_deprep(bus, SDW_BROADCAST_DEV_NUM);
1180                 if (ret < 0)
1181                         dev_warn(bus->dev, "clock stop deprepare wait failed:%d\n", ret);
1182         }
1183
1184         list_for_each_entry(slave, &bus->slaves, node) {
1185                 if (!slave->dev_num)
1186                         continue;
1187
1188                 if (slave->status != SDW_SLAVE_ATTACHED &&
1189                     slave->status != SDW_SLAVE_ALERT)
1190                         continue;
1191
1192                 ret = sdw_slave_clk_stop_callback(slave, SDW_CLK_STOP_MODE0,
1193                                                   SDW_CLK_POST_DEPREPARE);
1194                 if (ret < 0)
1195                         dev_warn(&slave->dev, "clock stop post-deprepare cb failed:%d\n", ret);
1196         }
1197
1198         return 0;
1199 }
1200 EXPORT_SYMBOL(sdw_bus_exit_clk_stop);
1201
1202 int sdw_configure_dpn_intr(struct sdw_slave *slave,
1203                            int port, bool enable, int mask)
1204 {
1205         u32 addr;
1206         int ret;
1207         u8 val = 0;
1208
1209         if (slave->bus->params.s_data_mode != SDW_PORT_DATA_MODE_NORMAL) {
1210                 dev_dbg(&slave->dev, "TEST FAIL interrupt %s\n",
1211                         enable ? "on" : "off");
1212                 mask |= SDW_DPN_INT_TEST_FAIL;
1213         }
1214
1215         addr = SDW_DPN_INTMASK(port);
1216
1217         /* Set/Clear port ready interrupt mask */
1218         if (enable) {
1219                 val |= mask;
1220                 val |= SDW_DPN_INT_PORT_READY;
1221         } else {
1222                 val &= ~(mask);
1223                 val &= ~SDW_DPN_INT_PORT_READY;
1224         }
1225
1226         ret = sdw_update_no_pm(slave, addr, (mask | SDW_DPN_INT_PORT_READY), val);
1227         if (ret < 0)
1228                 dev_err(&slave->dev,
1229                         "SDW_DPN_INTMASK write failed:%d\n", val);
1230
1231         return ret;
1232 }
1233
1234 static int sdw_slave_set_frequency(struct sdw_slave *slave)
1235 {
1236         u32 mclk_freq = slave->bus->prop.mclk_freq;
1237         u32 curr_freq = slave->bus->params.curr_dr_freq >> 1;
1238         unsigned int scale;
1239         u8 scale_index;
1240         u8 base;
1241         int ret;
1242
1243         /*
1244          * frequency base and scale registers are required for SDCA
1245          * devices. They may also be used for 1.2+/non-SDCA devices.
1246          * Driver can set the property, we will need a DisCo property
1247          * to discover this case from platform firmware.
1248          */
1249         if (!slave->id.class_id && !slave->prop.clock_reg_supported)
1250                 return 0;
1251
1252         if (!mclk_freq) {
1253                 dev_err(&slave->dev,
1254                         "no bus MCLK, cannot set SDW_SCP_BUS_CLOCK_BASE\n");
1255                 return -EINVAL;
1256         }
1257
1258         /*
1259          * map base frequency using Table 89 of SoundWire 1.2 spec.
1260          * The order of the tests just follows the specification, this
1261          * is not a selection between possible values or a search for
1262          * the best value but just a mapping.  Only one case per platform
1263          * is relevant.
1264          * Some BIOS have inconsistent values for mclk_freq but a
1265          * correct root so we force the mclk_freq to avoid variations.
1266          */
1267         if (!(19200000 % mclk_freq)) {
1268                 mclk_freq = 19200000;
1269                 base = SDW_SCP_BASE_CLOCK_19200000_HZ;
1270         } else if (!(24000000 % mclk_freq)) {
1271                 mclk_freq = 24000000;
1272                 base = SDW_SCP_BASE_CLOCK_24000000_HZ;
1273         } else if (!(24576000 % mclk_freq)) {
1274                 mclk_freq = 24576000;
1275                 base = SDW_SCP_BASE_CLOCK_24576000_HZ;
1276         } else if (!(22579200 % mclk_freq)) {
1277                 mclk_freq = 22579200;
1278                 base = SDW_SCP_BASE_CLOCK_22579200_HZ;
1279         } else if (!(32000000 % mclk_freq)) {
1280                 mclk_freq = 32000000;
1281                 base = SDW_SCP_BASE_CLOCK_32000000_HZ;
1282         } else {
1283                 dev_err(&slave->dev,
1284                         "Unsupported clock base, mclk %d\n",
1285                         mclk_freq);
1286                 return -EINVAL;
1287         }
1288
1289         if (mclk_freq % curr_freq) {
1290                 dev_err(&slave->dev,
1291                         "mclk %d is not multiple of bus curr_freq %d\n",
1292                         mclk_freq, curr_freq);
1293                 return -EINVAL;
1294         }
1295
1296         scale = mclk_freq / curr_freq;
1297
1298         /*
1299          * map scale to Table 90 of SoundWire 1.2 spec - and check
1300          * that the scale is a power of two and maximum 64
1301          */
1302         scale_index = ilog2(scale);
1303
1304         if (BIT(scale_index) != scale || scale_index > 6) {
1305                 dev_err(&slave->dev,
1306                         "No match found for scale %d, bus mclk %d curr_freq %d\n",
1307                         scale, mclk_freq, curr_freq);
1308                 return -EINVAL;
1309         }
1310         scale_index++;
1311
1312         ret = sdw_write_no_pm(slave, SDW_SCP_BUS_CLOCK_BASE, base);
1313         if (ret < 0) {
1314                 dev_err(&slave->dev,
1315                         "SDW_SCP_BUS_CLOCK_BASE write failed:%d\n", ret);
1316                 return ret;
1317         }
1318
1319         /* initialize scale for both banks */
1320         ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B0, scale_index);
1321         if (ret < 0) {
1322                 dev_err(&slave->dev,
1323                         "SDW_SCP_BUSCLOCK_SCALE_B0 write failed:%d\n", ret);
1324                 return ret;
1325         }
1326         ret = sdw_write_no_pm(slave, SDW_SCP_BUSCLOCK_SCALE_B1, scale_index);
1327         if (ret < 0)
1328                 dev_err(&slave->dev,
1329                         "SDW_SCP_BUSCLOCK_SCALE_B1 write failed:%d\n", ret);
1330
1331         dev_dbg(&slave->dev,
1332                 "Configured bus base %d, scale %d, mclk %d, curr_freq %d\n",
1333                 base, scale_index, mclk_freq, curr_freq);
1334
1335         return ret;
1336 }
1337
1338 static int sdw_initialize_slave(struct sdw_slave *slave)
1339 {
1340         struct sdw_slave_prop *prop = &slave->prop;
1341         int status;
1342         int ret;
1343         u8 val;
1344
1345         ret = sdw_slave_set_frequency(slave);
1346         if (ret < 0)
1347                 return ret;
1348
1349         if (slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH) {
1350                 /* Clear bus clash interrupt before enabling interrupt mask */
1351                 status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1352                 if (status < 0) {
1353                         dev_err(&slave->dev,
1354                                 "SDW_SCP_INT1 (BUS_CLASH) read failed:%d\n", status);
1355                         return status;
1356                 }
1357                 if (status & SDW_SCP_INT1_BUS_CLASH) {
1358                         dev_warn(&slave->dev, "Bus clash detected before INT mask is enabled\n");
1359                         ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_BUS_CLASH);
1360                         if (ret < 0) {
1361                                 dev_err(&slave->dev,
1362                                         "SDW_SCP_INT1 (BUS_CLASH) write failed:%d\n", ret);
1363                                 return ret;
1364                         }
1365                 }
1366         }
1367         if ((slave->bus->prop.quirks & SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY) &&
1368             !(slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY)) {
1369                 /* Clear parity interrupt before enabling interrupt mask */
1370                 status = sdw_read_no_pm(slave, SDW_SCP_INT1);
1371                 if (status < 0) {
1372                         dev_err(&slave->dev,
1373                                 "SDW_SCP_INT1 (PARITY) read failed:%d\n", status);
1374                         return status;
1375                 }
1376                 if (status & SDW_SCP_INT1_PARITY) {
1377                         dev_warn(&slave->dev, "PARITY error detected before INT mask is enabled\n");
1378                         ret = sdw_write_no_pm(slave, SDW_SCP_INT1, SDW_SCP_INT1_PARITY);
1379                         if (ret < 0) {
1380                                 dev_err(&slave->dev,
1381                                         "SDW_SCP_INT1 (PARITY) write failed:%d\n", ret);
1382                                 return ret;
1383                         }
1384                 }
1385         }
1386
1387         /*
1388          * Set SCP_INT1_MASK register, typically bus clash and
1389          * implementation-defined interrupt mask. The Parity detection
1390          * may not always be correct on startup so its use is
1391          * device-dependent, it might e.g. only be enabled in
1392          * steady-state after a couple of frames.
1393          */
1394         val = slave->prop.scp_int1_mask;
1395
1396         /* Enable SCP interrupts */
1397         ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val);
1398         if (ret < 0) {
1399                 dev_err(&slave->dev,
1400                         "SDW_SCP_INTMASK1 write failed:%d\n", ret);
1401                 return ret;
1402         }
1403
1404         /* No need to continue if DP0 is not present */
1405         if (!slave->prop.dp0_prop)
1406                 return 0;
1407
1408         /* Enable DP0 interrupts */
1409         val = prop->dp0_prop->imp_def_interrupts;
1410         val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE;
1411
1412         ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val);
1413         if (ret < 0)
1414                 dev_err(&slave->dev,
1415                         "SDW_DP0_INTMASK read failed:%d\n", ret);
1416         return ret;
1417 }
1418
1419 static int sdw_handle_dp0_interrupt(struct sdw_slave *slave, u8 *slave_status)
1420 {
1421         u8 clear, impl_int_mask;
1422         int status, status2, ret, count = 0;
1423
1424         status = sdw_read_no_pm(slave, SDW_DP0_INT);
1425         if (status < 0) {
1426                 dev_err(&slave->dev,
1427                         "SDW_DP0_INT read failed:%d\n", status);
1428                 return status;
1429         }
1430
1431         do {
1432                 clear = status & ~SDW_DP0_INTERRUPTS;
1433
1434                 if (status & SDW_DP0_INT_TEST_FAIL) {
1435                         dev_err(&slave->dev, "Test fail for port 0\n");
1436                         clear |= SDW_DP0_INT_TEST_FAIL;
1437                 }
1438
1439                 /*
1440                  * Assumption: PORT_READY interrupt will be received only for
1441                  * ports implementing Channel Prepare state machine (CP_SM)
1442                  */
1443
1444                 if (status & SDW_DP0_INT_PORT_READY) {
1445                         complete(&slave->port_ready[0]);
1446                         clear |= SDW_DP0_INT_PORT_READY;
1447                 }
1448
1449                 if (status & SDW_DP0_INT_BRA_FAILURE) {
1450                         dev_err(&slave->dev, "BRA failed\n");
1451                         clear |= SDW_DP0_INT_BRA_FAILURE;
1452                 }
1453
1454                 impl_int_mask = SDW_DP0_INT_IMPDEF1 |
1455                         SDW_DP0_INT_IMPDEF2 | SDW_DP0_INT_IMPDEF3;
1456
1457                 if (status & impl_int_mask) {
1458                         clear |= impl_int_mask;
1459                         *slave_status = clear;
1460                 }
1461
1462                 /* clear the interrupts but don't touch reserved and SDCA_CASCADE fields */
1463                 ret = sdw_write_no_pm(slave, SDW_DP0_INT, clear);
1464                 if (ret < 0) {
1465                         dev_err(&slave->dev,
1466                                 "SDW_DP0_INT write failed:%d\n", ret);
1467                         return ret;
1468                 }
1469
1470                 /* Read DP0 interrupt again */
1471                 status2 = sdw_read_no_pm(slave, SDW_DP0_INT);
1472                 if (status2 < 0) {
1473                         dev_err(&slave->dev,
1474                                 "SDW_DP0_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_DP0_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 DP0 read\n");
1487
1488         return ret;
1489 }
1490
1491 static int sdw_handle_port_interrupt(struct sdw_slave *slave,
1492                                      int port, u8 *slave_status)
1493 {
1494         u8 clear, impl_int_mask;
1495         int status, status2, ret, count = 0;
1496         u32 addr;
1497
1498         if (port == 0)
1499                 return sdw_handle_dp0_interrupt(slave, slave_status);
1500
1501         addr = SDW_DPN_INT(port);
1502         status = sdw_read_no_pm(slave, addr);
1503         if (status < 0) {
1504                 dev_err(&slave->dev,
1505                         "SDW_DPN_INT read failed:%d\n", status);
1506
1507                 return status;
1508         }
1509
1510         do {
1511                 clear = status & ~SDW_DPN_INTERRUPTS;
1512
1513                 if (status & SDW_DPN_INT_TEST_FAIL) {
1514                         dev_err(&slave->dev, "Test fail for port:%d\n", port);
1515                         clear |= SDW_DPN_INT_TEST_FAIL;
1516                 }
1517
1518                 /*
1519                  * Assumption: PORT_READY interrupt will be received only
1520                  * for ports implementing CP_SM.
1521                  */
1522                 if (status & SDW_DPN_INT_PORT_READY) {
1523                         complete(&slave->port_ready[port]);
1524                         clear |= SDW_DPN_INT_PORT_READY;
1525                 }
1526
1527                 impl_int_mask = SDW_DPN_INT_IMPDEF1 |
1528                         SDW_DPN_INT_IMPDEF2 | SDW_DPN_INT_IMPDEF3;
1529
1530                 if (status & impl_int_mask) {
1531                         clear |= impl_int_mask;
1532                         *slave_status = clear;
1533                 }
1534
1535                 /* clear the interrupt but don't touch reserved fields */
1536                 ret = sdw_write_no_pm(slave, addr, clear);
1537                 if (ret < 0) {
1538                         dev_err(&slave->dev,
1539                                 "SDW_DPN_INT write failed:%d\n", ret);
1540                         return ret;
1541                 }
1542
1543                 /* Read DPN interrupt again */
1544                 status2 = sdw_read_no_pm(slave, addr);
1545                 if (status2 < 0) {
1546                         dev_err(&slave->dev,
1547                                 "SDW_DPN_INT read failed:%d\n", status2);
1548                         return status2;
1549                 }
1550                 /* filter to limit loop to interrupts identified in the first status read */
1551                 status &= status2;
1552
1553                 count++;
1554
1555                 /* we can get alerts while processing so keep retrying */
1556         } while ((status & SDW_DPN_INTERRUPTS) && (count < SDW_READ_INTR_CLEAR_RETRY));
1557
1558         if (count == SDW_READ_INTR_CLEAR_RETRY)
1559                 dev_warn(&slave->dev, "Reached MAX_RETRY on port read");
1560
1561         return ret;
1562 }
1563
1564 static int sdw_handle_slave_alerts(struct sdw_slave *slave)
1565 {
1566         struct sdw_slave_intr_status slave_intr;
1567         u8 clear = 0, bit, port_status[15] = {0};
1568         int port_num, stat, ret, count = 0;
1569         unsigned long port;
1570         bool slave_notify;
1571         u8 sdca_cascade = 0;
1572         u8 buf, buf2[2], _buf, _buf2[2];
1573         bool parity_check;
1574         bool parity_quirk;
1575
1576         sdw_modify_slave_status(slave, SDW_SLAVE_ALERT);
1577
1578         ret = pm_runtime_resume_and_get(&slave->dev);
1579         if (ret < 0 && ret != -EACCES) {
1580                 dev_err(&slave->dev, "Failed to resume device: %d\n", ret);
1581                 return ret;
1582         }
1583
1584         /* Read Intstat 1, Intstat 2 and Intstat 3 registers */
1585         ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1586         if (ret < 0) {
1587                 dev_err(&slave->dev,
1588                         "SDW_SCP_INT1 read failed:%d\n", ret);
1589                 goto io_err;
1590         }
1591         buf = ret;
1592
1593         ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, buf2);
1594         if (ret < 0) {
1595                 dev_err(&slave->dev,
1596                         "SDW_SCP_INT2/3 read failed:%d\n", ret);
1597                 goto io_err;
1598         }
1599
1600         if (slave->id.class_id) {
1601                 ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1602                 if (ret < 0) {
1603                         dev_err(&slave->dev,
1604                                 "SDW_DP0_INT read failed:%d\n", ret);
1605                         goto io_err;
1606                 }
1607                 sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1608         }
1609
1610         do {
1611                 slave_notify = false;
1612
1613                 /*
1614                  * Check parity, bus clash and Slave (impl defined)
1615                  * interrupt
1616                  */
1617                 if (buf & SDW_SCP_INT1_PARITY) {
1618                         parity_check = slave->prop.scp_int1_mask & SDW_SCP_INT1_PARITY;
1619                         parity_quirk = !slave->first_interrupt_done &&
1620                                 (slave->prop.quirks & SDW_SLAVE_QUIRKS_INVALID_INITIAL_PARITY);
1621
1622                         if (parity_check && !parity_quirk)
1623                                 dev_err(&slave->dev, "Parity error detected\n");
1624                         clear |= SDW_SCP_INT1_PARITY;
1625                 }
1626
1627                 if (buf & SDW_SCP_INT1_BUS_CLASH) {
1628                         if (slave->prop.scp_int1_mask & SDW_SCP_INT1_BUS_CLASH)
1629                                 dev_err(&slave->dev, "Bus clash detected\n");
1630                         clear |= SDW_SCP_INT1_BUS_CLASH;
1631                 }
1632
1633                 /*
1634                  * When bus clash or parity errors are detected, such errors
1635                  * are unlikely to be recoverable errors.
1636                  * TODO: In such scenario, reset bus. Make this configurable
1637                  * via sysfs property with bus reset being the default.
1638                  */
1639
1640                 if (buf & SDW_SCP_INT1_IMPL_DEF) {
1641                         if (slave->prop.scp_int1_mask & SDW_SCP_INT1_IMPL_DEF) {
1642                                 dev_dbg(&slave->dev, "Slave impl defined interrupt\n");
1643                                 slave_notify = true;
1644                         }
1645                         clear |= SDW_SCP_INT1_IMPL_DEF;
1646                 }
1647
1648                 /* the SDCA interrupts are cleared in the codec driver .interrupt_callback() */
1649                 if (sdca_cascade)
1650                         slave_notify = true;
1651
1652                 /* Check port 0 - 3 interrupts */
1653                 port = buf & SDW_SCP_INT1_PORT0_3;
1654
1655                 /* To get port number corresponding to bits, shift it */
1656                 port = FIELD_GET(SDW_SCP_INT1_PORT0_3, port);
1657                 for_each_set_bit(bit, &port, 8) {
1658                         sdw_handle_port_interrupt(slave, bit,
1659                                                   &port_status[bit]);
1660                 }
1661
1662                 /* Check if cascade 2 interrupt is present */
1663                 if (buf & SDW_SCP_INT1_SCP2_CASCADE) {
1664                         port = buf2[0] & SDW_SCP_INTSTAT2_PORT4_10;
1665                         for_each_set_bit(bit, &port, 8) {
1666                                 /* scp2 ports start from 4 */
1667                                 port_num = bit + 4;
1668                                 sdw_handle_port_interrupt(slave,
1669                                                 port_num,
1670                                                 &port_status[port_num]);
1671                         }
1672                 }
1673
1674                 /* now check last cascade */
1675                 if (buf2[0] & SDW_SCP_INTSTAT2_SCP3_CASCADE) {
1676                         port = buf2[1] & SDW_SCP_INTSTAT3_PORT11_14;
1677                         for_each_set_bit(bit, &port, 8) {
1678                                 /* scp3 ports start from 11 */
1679                                 port_num = bit + 11;
1680                                 sdw_handle_port_interrupt(slave,
1681                                                 port_num,
1682                                                 &port_status[port_num]);
1683                         }
1684                 }
1685
1686                 /* Update the Slave driver */
1687                 if (slave_notify) {
1688                         mutex_lock(&slave->sdw_dev_lock);
1689
1690                         if (slave->probed) {
1691                                 struct device *dev = &slave->dev;
1692                                 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
1693
1694                                 if (drv->ops && drv->ops->interrupt_callback) {
1695                                         slave_intr.sdca_cascade = sdca_cascade;
1696                                         slave_intr.control_port = clear;
1697                                         memcpy(slave_intr.port, &port_status,
1698                                                sizeof(slave_intr.port));
1699
1700                                         drv->ops->interrupt_callback(slave, &slave_intr);
1701                                 }
1702                         }
1703
1704                         mutex_unlock(&slave->sdw_dev_lock);
1705                 }
1706
1707                 /* Ack interrupt */
1708                 ret = sdw_write_no_pm(slave, SDW_SCP_INT1, clear);
1709                 if (ret < 0) {
1710                         dev_err(&slave->dev,
1711                                 "SDW_SCP_INT1 write failed:%d\n", ret);
1712                         goto io_err;
1713                 }
1714
1715                 /* at this point all initial interrupt sources were handled */
1716                 slave->first_interrupt_done = true;
1717
1718                 /*
1719                  * Read status again to ensure no new interrupts arrived
1720                  * while servicing interrupts.
1721                  */
1722                 ret = sdw_read_no_pm(slave, SDW_SCP_INT1);
1723                 if (ret < 0) {
1724                         dev_err(&slave->dev,
1725                                 "SDW_SCP_INT1 recheck read failed:%d\n", ret);
1726                         goto io_err;
1727                 }
1728                 _buf = ret;
1729
1730                 ret = sdw_nread_no_pm(slave, SDW_SCP_INTSTAT2, 2, _buf2);
1731                 if (ret < 0) {
1732                         dev_err(&slave->dev,
1733                                 "SDW_SCP_INT2/3 recheck read failed:%d\n", ret);
1734                         goto io_err;
1735                 }
1736
1737                 if (slave->id.class_id) {
1738                         ret = sdw_read_no_pm(slave, SDW_DP0_INT);
1739                         if (ret < 0) {
1740                                 dev_err(&slave->dev,
1741                                         "SDW_DP0_INT recheck read failed:%d\n", ret);
1742                                 goto io_err;
1743                         }
1744                         sdca_cascade = ret & SDW_DP0_SDCA_CASCADE;
1745                 }
1746
1747                 /*
1748                  * Make sure no interrupts are pending, but filter to limit loop
1749                  * to interrupts identified in the first status read
1750                  */
1751                 buf &= _buf;
1752                 buf2[0] &= _buf2[0];
1753                 buf2[1] &= _buf2[1];
1754                 stat = buf || buf2[0] || buf2[1] || sdca_cascade;
1755
1756                 /*
1757                  * Exit loop if Slave is continuously in ALERT state even
1758                  * after servicing the interrupt multiple times.
1759                  */
1760                 count++;
1761
1762                 /* we can get alerts while processing so keep retrying */
1763         } while (stat != 0 && count < SDW_READ_INTR_CLEAR_RETRY);
1764
1765         if (count == SDW_READ_INTR_CLEAR_RETRY)
1766                 dev_warn(&slave->dev, "Reached MAX_RETRY on alert read\n");
1767
1768 io_err:
1769         pm_runtime_mark_last_busy(&slave->dev);
1770         pm_runtime_put_autosuspend(&slave->dev);
1771
1772         return ret;
1773 }
1774
1775 static int sdw_update_slave_status(struct sdw_slave *slave,
1776                                    enum sdw_slave_status status)
1777 {
1778         int ret = 0;
1779
1780         mutex_lock(&slave->sdw_dev_lock);
1781
1782         if (slave->probed) {
1783                 struct device *dev = &slave->dev;
1784                 struct sdw_driver *drv = drv_to_sdw_driver(dev->driver);
1785
1786                 if (drv->ops && drv->ops->update_status)
1787                         ret = drv->ops->update_status(slave, status);
1788         }
1789
1790         mutex_unlock(&slave->sdw_dev_lock);
1791
1792         return ret;
1793 }
1794
1795 /**
1796  * sdw_handle_slave_status() - Handle Slave status
1797  * @bus: SDW bus instance
1798  * @status: Status for all Slave(s)
1799  */
1800 int sdw_handle_slave_status(struct sdw_bus *bus,
1801                             enum sdw_slave_status status[])
1802 {
1803         enum sdw_slave_status prev_status;
1804         struct sdw_slave *slave;
1805         bool attached_initializing, id_programmed;
1806         int i, ret = 0;
1807
1808         /* first check if any Slaves fell off the bus */
1809         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1810                 mutex_lock(&bus->bus_lock);
1811                 if (test_bit(i, bus->assigned) == false) {
1812                         mutex_unlock(&bus->bus_lock);
1813                         continue;
1814                 }
1815                 mutex_unlock(&bus->bus_lock);
1816
1817                 slave = sdw_get_slave(bus, i);
1818                 if (!slave)
1819                         continue;
1820
1821                 if (status[i] == SDW_SLAVE_UNATTACHED &&
1822                     slave->status != SDW_SLAVE_UNATTACHED) {
1823                         dev_warn(&slave->dev, "Slave %d state check1: UNATTACHED, status was %d\n",
1824                                  i, slave->status);
1825                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1826
1827                         /* Ensure driver knows that peripheral unattached */
1828                         ret = sdw_update_slave_status(slave, status[i]);
1829                         if (ret < 0)
1830                                 dev_warn(&slave->dev, "Update Slave status failed:%d\n", ret);
1831                 }
1832         }
1833
1834         if (status[0] == SDW_SLAVE_ATTACHED) {
1835                 dev_dbg(bus->dev, "Slave attached, programming device number\n");
1836
1837                 /*
1838                  * Programming a device number will have side effects,
1839                  * so we deal with other devices at a later time.
1840                  * This relies on those devices reporting ATTACHED, which will
1841                  * trigger another call to this function. This will only
1842                  * happen if at least one device ID was programmed.
1843                  * Error returns from sdw_program_device_num() are currently
1844                  * ignored because there's no useful recovery that can be done.
1845                  * Returning the error here could result in the current status
1846                  * of other devices not being handled, because if no device IDs
1847                  * were programmed there's nothing to guarantee a status change
1848                  * to trigger another call to this function.
1849                  */
1850                 sdw_program_device_num(bus, &id_programmed);
1851                 if (id_programmed)
1852                         return 0;
1853         }
1854
1855         /* Continue to check other slave statuses */
1856         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1857                 mutex_lock(&bus->bus_lock);
1858                 if (test_bit(i, bus->assigned) == false) {
1859                         mutex_unlock(&bus->bus_lock);
1860                         continue;
1861                 }
1862                 mutex_unlock(&bus->bus_lock);
1863
1864                 slave = sdw_get_slave(bus, i);
1865                 if (!slave)
1866                         continue;
1867
1868                 attached_initializing = false;
1869
1870                 switch (status[i]) {
1871                 case SDW_SLAVE_UNATTACHED:
1872                         if (slave->status == SDW_SLAVE_UNATTACHED)
1873                                 break;
1874
1875                         dev_warn(&slave->dev, "Slave %d state check2: UNATTACHED, status was %d\n",
1876                                  i, slave->status);
1877
1878                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1879                         break;
1880
1881                 case SDW_SLAVE_ALERT:
1882                         ret = sdw_handle_slave_alerts(slave);
1883                         if (ret < 0)
1884                                 dev_err(&slave->dev,
1885                                         "Slave %d alert handling failed: %d\n",
1886                                         i, ret);
1887                         break;
1888
1889                 case SDW_SLAVE_ATTACHED:
1890                         if (slave->status == SDW_SLAVE_ATTACHED)
1891                                 break;
1892
1893                         prev_status = slave->status;
1894                         sdw_modify_slave_status(slave, SDW_SLAVE_ATTACHED);
1895
1896                         if (prev_status == SDW_SLAVE_ALERT)
1897                                 break;
1898
1899                         attached_initializing = true;
1900
1901                         ret = sdw_initialize_slave(slave);
1902                         if (ret < 0)
1903                                 dev_err(&slave->dev,
1904                                         "Slave %d initialization failed: %d\n",
1905                                         i, ret);
1906
1907                         break;
1908
1909                 default:
1910                         dev_err(&slave->dev, "Invalid slave %d status:%d\n",
1911                                 i, status[i]);
1912                         break;
1913                 }
1914
1915                 ret = sdw_update_slave_status(slave, status[i]);
1916                 if (ret < 0)
1917                         dev_err(&slave->dev,
1918                                 "Update Slave status failed:%d\n", ret);
1919                 if (attached_initializing) {
1920                         dev_dbg(&slave->dev,
1921                                 "signaling initialization completion for Slave %d\n",
1922                                 slave->dev_num);
1923
1924                         complete(&slave->initialization_complete);
1925
1926                         /*
1927                          * If the manager became pm_runtime active, the peripherals will be
1928                          * restarted and attach, but their pm_runtime status may remain
1929                          * suspended. If the 'update_slave_status' callback initiates
1930                          * any sort of deferred processing, this processing would not be
1931                          * cancelled on pm_runtime suspend.
1932                          * To avoid such zombie states, we queue a request to resume.
1933                          * This would be a no-op in case the peripheral was being resumed
1934                          * by e.g. the ALSA/ASoC framework.
1935                          */
1936                         pm_request_resume(&slave->dev);
1937                 }
1938         }
1939
1940         return ret;
1941 }
1942 EXPORT_SYMBOL(sdw_handle_slave_status);
1943
1944 void sdw_clear_slave_status(struct sdw_bus *bus, u32 request)
1945 {
1946         struct sdw_slave *slave;
1947         int i;
1948
1949         /* Check all non-zero devices */
1950         for (i = 1; i <= SDW_MAX_DEVICES; i++) {
1951                 mutex_lock(&bus->bus_lock);
1952                 if (test_bit(i, bus->assigned) == false) {
1953                         mutex_unlock(&bus->bus_lock);
1954                         continue;
1955                 }
1956                 mutex_unlock(&bus->bus_lock);
1957
1958                 slave = sdw_get_slave(bus, i);
1959                 if (!slave)
1960                         continue;
1961
1962                 if (slave->status != SDW_SLAVE_UNATTACHED) {
1963                         sdw_modify_slave_status(slave, SDW_SLAVE_UNATTACHED);
1964                         slave->first_interrupt_done = false;
1965                         sdw_update_slave_status(slave, SDW_SLAVE_UNATTACHED);
1966                 }
1967
1968                 /* keep track of request, used in pm_runtime resume */
1969                 slave->unattach_request = request;
1970         }
1971 }
1972 EXPORT_SYMBOL(sdw_clear_slave_status);