drivers/soundwire/intel_auxdevice.c

   1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
   2 // Copyright(c) 2015-22 Intel Corporation.
   3
   4 /*
   5  * Soundwire Intel Manager Driver
   6  */
   7
   8 #include <linux/acpi.h>
   9 #include <linux/debugfs.h>
  10 #include <linux/delay.h>
  11 #include <linux/module.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/io.h>
  14 #include <linux/auxiliary_bus.h>
  15 #include <sound/pcm_params.h>
  16 #include <linux/pm_runtime.h>
  17 #include <sound/soc.h>
  18 #include <linux/soundwire/sdw_registers.h>
  19 #include <linux/soundwire/sdw.h>
  20 #include <linux/soundwire/sdw_intel.h>
  21 #include "cadence_master.h"
  22 #include "bus.h"
  23 #include "intel.h"
  24 #include "intel_auxdevice.h"
  25
  26 /* IDA min selected to avoid conflicts with HDaudio/iDISP SDI values */
  27 #define INTEL_DEV_NUM_IDA_MIN           4
  28
  29 #define INTEL_MASTER_SUSPEND_DELAY_MS   3000
  30
  31 /*
  32  * debug/config flags for the Intel SoundWire Master.
  33  *
  34  * Since we may have multiple masters active, we can have up to 8
  35  * flags reused in each byte, with master0 using the ls-byte, etc.
  36  */
  37
  38 #define SDW_INTEL_MASTER_DISABLE_PM_RUNTIME             BIT(0)
  39 #define SDW_INTEL_MASTER_DISABLE_CLOCK_STOP             BIT(1)
  40 #define SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE        BIT(2)
  41 #define SDW_INTEL_MASTER_DISABLE_MULTI_LINK             BIT(3)
  42
  43 static int md_flags;
  44 module_param_named(sdw_md_flags, md_flags, int, 0444);
  45 MODULE_PARM_DESC(sdw_md_flags, "SoundWire Intel Master device flags (0x0 all off)");
  46
  47 static int generic_pre_bank_switch(struct sdw_bus *bus)
  48 {
  49         struct sdw_cdns *cdns = bus_to_cdns(bus);
  50         struct sdw_intel *sdw = cdns_to_intel(cdns);
  51
  52         return sdw->link_res->hw_ops->pre_bank_switch(sdw);
  53 }
  54
  55 static int generic_post_bank_switch(struct sdw_bus *bus)
  56 {
  57         struct sdw_cdns *cdns = bus_to_cdns(bus);
  58         struct sdw_intel *sdw = cdns_to_intel(cdns);
  59
  60         return sdw->link_res->hw_ops->post_bank_switch(sdw);
  61 }
  62
  63 static int sdw_master_read_intel_prop(struct sdw_bus *bus)
  64 {
  65         struct sdw_master_prop *prop = &bus->prop;
  66         struct fwnode_handle *link;
  67         char name[32];
  68         u32 quirk_mask;
  69
  70         /* Find master handle */
  71         snprintf(name, sizeof(name),
  72                  "mipi-sdw-link-%d-subproperties", bus->link_id);
  73
  74         link = device_get_named_child_node(bus->dev, name);
  75         if (!link) {
  76                 dev_err(bus->dev, "Master node %s not found\n", name);
  77                 return -EIO;
  78         }
  79
  80         fwnode_property_read_u32(link,
  81                                  "intel-sdw-ip-clock",
  82                                  &prop->mclk_freq);
  83
  84         /* the values reported by BIOS are the 2x clock, not the bus clock */
  85         prop->mclk_freq /= 2;
  86
  87         fwnode_property_read_u32(link,
  88                                  "intel-quirk-mask",
  89                                  &quirk_mask);
  90
  91         if (quirk_mask & SDW_INTEL_QUIRK_MASK_BUS_DISABLE)
  92                 prop->hw_disabled = true;
  93
  94         prop->quirks = SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH |
  95                 SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY;
  96
  97         return 0;
  98 }
  99
 100 static int intel_prop_read(struct sdw_bus *bus)
 101 {
 102         /* Initialize with default handler to read all DisCo properties */
 103         sdw_master_read_prop(bus);
 104
 105         /* read Intel-specific properties */
 106         sdw_master_read_intel_prop(bus);
 107
 108         return 0;
 109 }
 110
 111 static struct sdw_master_ops sdw_intel_ops = {
 112         .read_prop = intel_prop_read,
 113         .override_adr = sdw_dmi_override_adr,
 114         .xfer_msg = cdns_xfer_msg,
 115         .xfer_msg_defer = cdns_xfer_msg_defer,
 116         .reset_page_addr = cdns_reset_page_addr,
 117         .set_bus_conf = cdns_bus_conf,
 118         .pre_bank_switch = generic_pre_bank_switch,
 119         .post_bank_switch = generic_post_bank_switch,
 120         .read_ping_status = cdns_read_ping_status,
 121 };
 122
 123 /*
 124  * probe and init (aux_dev_id argument is required by function prototype but not used)
 125  */
 126 static int intel_link_probe(struct auxiliary_device *auxdev,
 127                             const struct auxiliary_device_id *aux_dev_id)
 128
 129 {
 130         struct device *dev = &auxdev->dev;
 131         struct sdw_intel_link_dev *ldev = auxiliary_dev_to_sdw_intel_link_dev(auxdev);
 132         struct sdw_intel *sdw;
 133         struct sdw_cdns *cdns;
 134         struct sdw_bus *bus;
 135         int ret;
 136
 137         sdw = devm_kzalloc(dev, sizeof(*sdw), GFP_KERNEL);
 138         if (!sdw)
 139                 return -ENOMEM;
 140
 141         cdns = &sdw->cdns;
 142         bus = &cdns->bus;
 143
 144         sdw->instance = auxdev->id;
 145         sdw->link_res = &ldev->link_res;
 146         cdns->dev = dev;
 147         cdns->registers = sdw->link_res->registers;
 148         cdns->instance = sdw->instance;
 149         cdns->msg_count = 0;
 150
 151         bus->link_id = auxdev->id;
 152         bus->dev_num_ida_min = INTEL_DEV_NUM_IDA_MIN;
 153         bus->clk_stop_timeout = 1;
 154
 155         sdw_cdns_probe(cdns);
 156
 157         /* Set ops */
 158         bus->ops = &sdw_intel_ops;
 159
 160         /* set driver data, accessed by snd_soc_dai_get_drvdata() */
 161         auxiliary_set_drvdata(auxdev, cdns);
 162
 163         /* use generic bandwidth allocation algorithm */
 164         sdw->cdns.bus.compute_params = sdw_compute_params;
 165
 166         /* avoid resuming from pm_runtime suspend if it's not required */
 167         dev_pm_set_driver_flags(dev, DPM_FLAG_SMART_SUSPEND);
 168
 169         ret = sdw_bus_master_add(bus, dev, dev->fwnode);
 170         if (ret) {
 171                 dev_err(dev, "sdw_bus_master_add fail: %d\n", ret);
 172                 return ret;
 173         }
 174
 175         if (bus->prop.hw_disabled)
 176                 dev_info(dev,
 177                          "SoundWire master %d is disabled, will be ignored\n",
 178                          bus->link_id);
 179         /*
 180          * Ignore BIOS err_threshold, it's a really bad idea when dealing
 181          * with multiple hardware synchronized links
 182          */
 183         bus->prop.err_threshold = 0;
 184
 185         return 0;
 186 }
 187
 188 int intel_link_startup(struct auxiliary_device *auxdev)
 189 {
 190         struct device *dev = &auxdev->dev;
 191         struct sdw_cdns *cdns = auxiliary_get_drvdata(auxdev);
 192         struct sdw_intel *sdw = cdns_to_intel(cdns);
 193         struct sdw_bus *bus = &cdns->bus;
 194         int link_flags;
 195         bool multi_link;
 196         u32 clock_stop_quirks;
 197         int ret;
 198
 199         if (bus->prop.hw_disabled) {
 200                 dev_info(dev,
 201                          "SoundWire master %d is disabled, ignoring\n",
 202                          sdw->instance);
 203                 return 0;
 204         }
 205
 206         link_flags = md_flags >> (bus->link_id * 8);
 207         multi_link = !(link_flags & SDW_INTEL_MASTER_DISABLE_MULTI_LINK);
 208         if (!multi_link) {
 209                 dev_dbg(dev, "Multi-link is disabled\n");
 210         } else {
 211                 /*
 212                  * hardware-based synchronization is required regardless
 213                  * of the number of segments used by a stream: SSP-based
 214                  * synchronization is gated by gsync when the multi-master
 215                  * mode is set.
 216                  */
 217                 bus->hw_sync_min_links = 1;
 218         }
 219         bus->multi_link = multi_link;
 220
 221         /* Initialize shim, controller */
 222         ret = sdw_intel_link_power_up(sdw);
 223         if (ret)
 224                 goto err_init;
 225
 226         /* Register DAIs */
 227         ret = sdw_intel_register_dai(sdw);
 228         if (ret) {
 229                 dev_err(dev, "DAI registration failed: %d\n", ret);
 230                 goto err_power_up;
 231         }
 232
 233         sdw_intel_debugfs_init(sdw);
 234
 235         /* start bus */
 236         ret = sdw_intel_start_bus(sdw);
 237         if (ret) {
 238                 dev_err(dev, "bus start failed: %d\n", ret);
 239                 goto err_power_up;
 240         }
 241
 242         /* Enable runtime PM */
 243         if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME)) {
 244                 pm_runtime_set_autosuspend_delay(dev,
 245                                                  INTEL_MASTER_SUSPEND_DELAY_MS);
 246                 pm_runtime_use_autosuspend(dev);
 247                 pm_runtime_mark_last_busy(dev);
 248
 249                 pm_runtime_set_active(dev);
 250                 pm_runtime_enable(dev);
 251         }
 252
 253         clock_stop_quirks = sdw->link_res->clock_stop_quirks;
 254         if (clock_stop_quirks & SDW_INTEL_CLK_STOP_NOT_ALLOWED) {
 255                 /*
 256                  * To keep the clock running we need to prevent
 257                  * pm_runtime suspend from happening by increasing the
 258                  * reference count.
 259                  * This quirk is specified by the parent PCI device in
 260                  * case of specific latency requirements. It will have
 261                  * no effect if pm_runtime is disabled by the user via
 262                  * a module parameter for testing purposes.
 263                  */
 264                 pm_runtime_get_noresume(dev);
 265         }
 266
 267         /*
 268          * The runtime PM status of Slave devices is "Unsupported"
 269          * until they report as ATTACHED. If they don't, e.g. because
 270          * there are no Slave devices populated or if the power-on is
 271          * delayed or dependent on a power switch, the Master will
 272          * remain active and prevent its parent from suspending.
 273          *
 274          * Conditionally force the pm_runtime core to re-evaluate the
 275          * Master status in the absence of any Slave activity. A quirk
 276          * is provided to e.g. deal with Slaves that may be powered on
 277          * with a delay. A more complete solution would require the
 278          * definition of Master properties.
 279          */
 280         if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE))
 281                 pm_runtime_idle(dev);
 282
 283         sdw->startup_done = true;
 284         return 0;
 285
 286 err_power_up:
 287         sdw_intel_link_power_down(sdw);
 288 err_init:
 289         return ret;
 290 }
 291
 292 static void intel_link_remove(struct auxiliary_device *auxdev)
 293 {
 294         struct sdw_cdns *cdns = auxiliary_get_drvdata(auxdev);
 295         struct sdw_intel *sdw = cdns_to_intel(cdns);
 296         struct sdw_bus *bus = &cdns->bus;
 297
 298         /*
 299          * Since pm_runtime is already disabled, we don't decrease
 300          * the refcount when the clock_stop_quirk is
 301          * SDW_INTEL_CLK_STOP_NOT_ALLOWED
 302          */
 303         if (!bus->prop.hw_disabled) {
 304                 sdw_intel_debugfs_exit(sdw);
 305                 sdw_cdns_enable_interrupt(cdns, false);
 306         }
 307         sdw_bus_master_delete(bus);
 308 }
 309
 310 int intel_link_process_wakeen_event(struct auxiliary_device *auxdev)
 311 {
 312         struct device *dev = &auxdev->dev;
 313         struct sdw_intel *sdw;
 314         struct sdw_bus *bus;
 315
 316         sdw = auxiliary_get_drvdata(auxdev);
 317         bus = &sdw->cdns.bus;
 318
 319         if (bus->prop.hw_disabled || !sdw->startup_done) {
 320                 dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
 321                         bus->link_id);
 322                 return 0;
 323         }
 324
 325         if (!sdw_intel_shim_check_wake(sdw))
 326                 return 0;
 327
 328         /* disable WAKEEN interrupt ASAP to prevent interrupt flood */
 329         sdw_intel_shim_wake(sdw, false);
 330
 331         /*
 332          * resume the Master, which will generate a bus reset and result in
 333          * Slaves re-attaching and be re-enumerated. The SoundWire physical
 334          * device which generated the wake will trigger an interrupt, which
 335          * will in turn cause the corresponding Linux Slave device to be
 336          * resumed and the Slave codec driver to check the status.
 337          */
 338         pm_request_resume(dev);
 339
 340         return 0;
 341 }
 342
 343 /*
 344  * PM calls
 345  */
 346
 347 static int intel_resume_child_device(struct device *dev, void *data)
 348 {
 349         int ret;
 350         struct sdw_slave *slave = dev_to_sdw_dev(dev);
 351
 352         if (!slave->probed) {
 353                 dev_dbg(dev, "skipping device, no probed driver\n");
 354                 return 0;
 355         }
 356         if (!slave->dev_num_sticky) {
 357                 dev_dbg(dev, "skipping device, never detected on bus\n");
 358                 return 0;
 359         }
 360
 361         ret = pm_request_resume(dev);
 362         if (ret < 0)
 363                 dev_err(dev, "%s: pm_request_resume failed: %d\n", __func__, ret);
 364
 365         return ret;
 366 }
 367
 368 static int __maybe_unused intel_pm_prepare(struct device *dev)
 369 {
 370         struct sdw_cdns *cdns = dev_get_drvdata(dev);
 371         struct sdw_intel *sdw = cdns_to_intel(cdns);
 372         struct sdw_bus *bus = &cdns->bus;
 373         u32 clock_stop_quirks;
 374         int ret;
 375
 376         if (bus->prop.hw_disabled || !sdw->startup_done) {
 377                 dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
 378                         bus->link_id);
 379                 return 0;
 380         }
 381
 382         clock_stop_quirks = sdw->link_res->clock_stop_quirks;
 383
 384         if (pm_runtime_suspended(dev) &&
 385             pm_runtime_suspended(dev->parent) &&
 386             ((clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) ||
 387              !clock_stop_quirks)) {
 388                 /*
 389                  * if we've enabled clock stop, and the parent is suspended, the SHIM registers
 390                  * are not accessible and the shim wake cannot be disabled.
 391                  * The only solution is to resume the entire bus to full power
 392                  */
 393
 394                 /*
 395                  * If any operation in this block fails, we keep going since we don't want
 396                  * to prevent system suspend from happening and errors should be recoverable
 397                  * on resume.
 398                  */
 399
 400                 /*
 401                  * first resume the device for this link. This will also by construction
 402                  * resume the PCI parent device.
 403                  */
 404                 ret = pm_request_resume(dev);
 405                 if (ret < 0) {
 406                         dev_err(dev, "%s: pm_request_resume failed: %d\n", __func__, ret);
 407                         return 0;
 408                 }
 409
 410                 /*
 411                  * Continue resuming the entire bus (parent + child devices) to exit
 412                  * the clock stop mode. If there are no devices connected on this link
 413                  * this is a no-op.
 414                  * The resume to full power could have been implemented with a .prepare
 415                  * step in SoundWire codec drivers. This would however require a lot
 416                  * of code to handle an Intel-specific corner case. It is simpler in
 417                  * practice to add a loop at the link level.
 418                  */
 419                 ret = device_for_each_child(bus->dev, NULL, intel_resume_child_device);
 420
 421                 if (ret < 0)
 422                         dev_err(dev, "%s: intel_resume_child_device failed: %d\n", __func__, ret);
 423         }
 424
 425         return 0;
 426 }
 427
 428 static int __maybe_unused intel_suspend(struct device *dev)
 429 {
 430         struct sdw_cdns *cdns = dev_get_drvdata(dev);
 431         struct sdw_intel *sdw = cdns_to_intel(cdns);
 432         struct sdw_bus *bus = &cdns->bus;
 433         u32 clock_stop_quirks;
 434         int ret;
 435
 436         if (bus->prop.hw_disabled || !sdw->startup_done) {
 437                 dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
 438                         bus->link_id);
 439                 return 0;
 440         }
 441
 442         if (pm_runtime_suspended(dev)) {
 443                 dev_dbg(dev, "pm_runtime status: suspended\n");
 444
 445                 clock_stop_quirks = sdw->link_res->clock_stop_quirks;
 446
 447                 if ((clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) ||
 448                     !clock_stop_quirks) {
 449
 450                         if (pm_runtime_suspended(dev->parent)) {
 451                                 /*
 452                                  * paranoia check: this should not happen with the .prepare
 453                                  * resume to full power
 454                                  */
 455                                 dev_err(dev, "%s: invalid config: parent is suspended\n", __func__);
 456                         } else {
 457                                 sdw_intel_shim_wake(sdw, false);
 458                         }
 459                 }
 460
 461                 return 0;
 462         }
 463
 464         ret = sdw_intel_stop_bus(sdw, false);
 465         if (ret < 0) {
 466                 dev_err(dev, "%s: cannot stop bus: %d\n", __func__, ret);
 467                 return ret;
 468         }
 469
 470         return 0;
 471 }
 472
 473 static int __maybe_unused intel_suspend_runtime(struct device *dev)
 474 {
 475         struct sdw_cdns *cdns = dev_get_drvdata(dev);
 476         struct sdw_intel *sdw = cdns_to_intel(cdns);
 477         struct sdw_bus *bus = &cdns->bus;
 478         u32 clock_stop_quirks;
 479         int ret;
 480
 481         if (bus->prop.hw_disabled || !sdw->startup_done) {
 482                 dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
 483                         bus->link_id);
 484                 return 0;
 485         }
 486
 487         clock_stop_quirks = sdw->link_res->clock_stop_quirks;
 488
 489         if (clock_stop_quirks & SDW_INTEL_CLK_STOP_TEARDOWN) {
 490                 ret = sdw_intel_stop_bus(sdw, false);
 491                 if (ret < 0) {
 492                         dev_err(dev, "%s: cannot stop bus during teardown: %d\n",
 493                                 __func__, ret);
 494                         return ret;
 495                 }
 496         } else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET || !clock_stop_quirks) {
 497                 ret = sdw_intel_stop_bus(sdw, true);
 498                 if (ret < 0) {
 499                         dev_err(dev, "%s: cannot stop bus during clock_stop: %d\n",
 500                                 __func__, ret);
 501                         return ret;
 502                 }
 503         } else {
 504                 dev_err(dev, "%s clock_stop_quirks %x unsupported\n",
 505                         __func__, clock_stop_quirks);
 506                 ret = -EINVAL;
 507         }
 508
 509         return ret;
 510 }
 511
 512 static int __maybe_unused intel_resume(struct device *dev)
 513 {
 514         struct sdw_cdns *cdns = dev_get_drvdata(dev);
 515         struct sdw_intel *sdw = cdns_to_intel(cdns);
 516         struct sdw_bus *bus = &cdns->bus;
 517         int link_flags;
 518         int ret;
 519
 520         if (bus->prop.hw_disabled || !sdw->startup_done) {
 521                 dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
 522                         bus->link_id);
 523                 return 0;
 524         }
 525
 526         link_flags = md_flags >> (bus->link_id * 8);
 527
 528         if (pm_runtime_suspended(dev)) {
 529                 dev_dbg(dev, "pm_runtime status was suspended, forcing active\n");
 530
 531                 /* follow required sequence from runtime_pm.rst */
 532                 pm_runtime_disable(dev);
 533                 pm_runtime_set_active(dev);
 534                 pm_runtime_mark_last_busy(dev);
 535                 pm_runtime_enable(dev);
 536
 537                 link_flags = md_flags >> (bus->link_id * 8);
 538
 539                 if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE))
 540                         pm_runtime_idle(dev);
 541         }
 542
 543         ret = sdw_intel_link_power_up(sdw);
 544         if (ret) {
 545                 dev_err(dev, "%s failed: %d\n", __func__, ret);
 546                 return ret;
 547         }
 548
 549         /*
 550          * make sure all Slaves are tagged as UNATTACHED and provide
 551          * reason for reinitialization
 552          */
 553         sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET);
 554
 555         ret = sdw_intel_start_bus(sdw);
 556         if (ret < 0) {
 557                 dev_err(dev, "cannot start bus during resume\n");
 558                 sdw_intel_link_power_down(sdw);
 559                 return ret;
 560         }
 561
 562         /*
 563          * after system resume, the pm_runtime suspend() may kick in
 564          * during the enumeration, before any children device force the
 565          * master device to remain active.  Using pm_runtime_get()
 566          * routines is not really possible, since it'd prevent the
 567          * master from suspending.
 568          * A reasonable compromise is to update the pm_runtime
 569          * counters and delay the pm_runtime suspend by several
 570          * seconds, by when all enumeration should be complete.
 571          */
 572         pm_runtime_mark_last_busy(dev);
 573
 574         return 0;
 575 }
 576
 577 static int __maybe_unused intel_resume_runtime(struct device *dev)
 578 {
 579         struct sdw_cdns *cdns = dev_get_drvdata(dev);
 580         struct sdw_intel *sdw = cdns_to_intel(cdns);
 581         struct sdw_bus *bus = &cdns->bus;
 582         u32 clock_stop_quirks;
 583         int ret;
 584
 585         if (bus->prop.hw_disabled || !sdw->startup_done) {
 586                 dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
 587                         bus->link_id);
 588                 return 0;
 589         }
 590
 591         /* unconditionally disable WAKEEN interrupt */
 592         sdw_intel_shim_wake(sdw, false);
 593
 594         clock_stop_quirks = sdw->link_res->clock_stop_quirks;
 595
 596         if (clock_stop_quirks & SDW_INTEL_CLK_STOP_TEARDOWN) {
 597                 ret = sdw_intel_link_power_up(sdw);
 598                 if (ret) {
 599                         dev_err(dev, "%s: power_up failed after teardown: %d\n", __func__, ret);
 600                         return ret;
 601                 }
 602
 603                 /*
 604                  * make sure all Slaves are tagged as UNATTACHED and provide
 605                  * reason for reinitialization
 606                  */
 607                 sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET);
 608
 609                 ret = sdw_intel_start_bus(sdw);
 610                 if (ret < 0) {
 611                         dev_err(dev, "%s: cannot start bus after teardown: %d\n", __func__, ret);
 612                         sdw_intel_link_power_down(sdw);
 613                         return ret;
 614                 }
 615
 616         } else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) {
 617                 ret = sdw_intel_link_power_up(sdw);
 618                 if (ret) {
 619                         dev_err(dev, "%s: power_up failed after bus reset: %d\n", __func__, ret);
 620                         return ret;
 621                 }
 622
 623                 ret = sdw_intel_start_bus_after_reset(sdw);
 624                 if (ret < 0) {
 625                         dev_err(dev, "%s: cannot start bus after reset: %d\n", __func__, ret);
 626                         sdw_intel_link_power_down(sdw);
 627                         return ret;
 628                 }
 629         } else if (!clock_stop_quirks) {
 630
 631                 sdw_intel_check_clock_stop(sdw);
 632
 633                 ret = sdw_intel_link_power_up(sdw);
 634                 if (ret) {
 635                         dev_err(dev, "%s: power_up failed: %d\n", __func__, ret);
 636                         return ret;
 637                 }
 638
 639                 ret = sdw_intel_start_bus_after_clock_stop(sdw);
 640                 if (ret < 0) {
 641                         dev_err(dev, "%s: cannot start bus after clock stop: %d\n", __func__, ret);
 642                         sdw_intel_link_power_down(sdw);
 643                         return ret;
 644                 }
 645         } else {
 646                 dev_err(dev, "%s: clock_stop_quirks %x unsupported\n",
 647                         __func__, clock_stop_quirks);
 648                 ret = -EINVAL;
 649         }
 650
 651         return ret;
 652 }
 653
 654 static const struct dev_pm_ops intel_pm = {
 655         .prepare = intel_pm_prepare,
 656         SET_SYSTEM_SLEEP_PM_OPS(intel_suspend, intel_resume)
 657         SET_RUNTIME_PM_OPS(intel_suspend_runtime, intel_resume_runtime, NULL)
 658 };
 659
 660 static const struct auxiliary_device_id intel_link_id_table[] = {
 661         { .name = "soundwire_intel.link" },
 662         {},
 663 };
 664 MODULE_DEVICE_TABLE(auxiliary, intel_link_id_table);
 665
 666 static struct auxiliary_driver sdw_intel_drv = {
 667         .probe = intel_link_probe,
 668         .remove = intel_link_remove,
 669         .driver = {
 670                 /* auxiliary_driver_register() sets .name to be the modname */
 671                 .pm = &intel_pm,
 672         },
 673         .id_table = intel_link_id_table
 674 };
 675 module_auxiliary_driver(sdw_intel_drv);
 676
 677 MODULE_LICENSE("Dual BSD/GPL");
 678 MODULE_DESCRIPTION("Intel Soundwire Link Driver");