drivers/thermal/thermal_core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  thermal.c - Generic Thermal Management Sysfs support.
   4  *
   5  *  Copyright (C) 2008 Intel Corp
   6  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   7  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
   8  */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/device.h>
  13 #include <linux/err.h>
  14 #include <linux/export.h>
  15 #include <linux/slab.h>
  16 #include <linux/kdev_t.h>
  17 #include <linux/idr.h>
  18 #include <linux/thermal.h>
  19 #include <linux/reboot.h>
  20 #include <linux/string.h>
  21 #include <linux/of.h>
  22 #include <linux/suspend.h>
  23
  24 #define CREATE_TRACE_POINTS
  25 #include <trace/events/thermal.h>
  26
  27 #include "thermal_core.h"
  28 #include "thermal_hwmon.h"
  29
  30 static DEFINE_IDA(thermal_tz_ida);
  31 static DEFINE_IDA(thermal_cdev_ida);
  32
  33 static LIST_HEAD(thermal_tz_list);
  34 static LIST_HEAD(thermal_cdev_list);
  35 static LIST_HEAD(thermal_governor_list);
  36
  37 static DEFINE_MUTEX(thermal_list_lock);
  38 static DEFINE_MUTEX(thermal_governor_lock);
  39
  40 static atomic_t in_suspend;
  41
  42 static struct thermal_governor *def_governor;
  43
  44 /*
  45  * Governor section: set of functions to handle thermal governors
  46  *
  47  * Functions to help in the life cycle of thermal governors within
  48  * the thermal core and by the thermal governor code.
  49  */
  50
  51 static struct thermal_governor *__find_governor(const char *name)
  52 {
  53         struct thermal_governor *pos;
  54
  55         if (!name || !name[0])
  56                 return def_governor;
  57
  58         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  59                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  60                         return pos;
  61
  62         return NULL;
  63 }
  64
  65 /**
  66  * bind_previous_governor() - bind the previous governor of the thermal zone
  67  * @tz:         a valid pointer to a struct thermal_zone_device
  68  * @failed_gov_name:    the name of the governor that failed to register
  69  *
  70  * Register the previous governor of the thermal zone after a new
  71  * governor has failed to be bound.
  72  */
  73 static void bind_previous_governor(struct thermal_zone_device *tz,
  74                                    const char *failed_gov_name)
  75 {
  76         if (tz->governor && tz->governor->bind_to_tz) {
  77                 if (tz->governor->bind_to_tz(tz)) {
  78                         dev_err(&tz->device,
  79                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  80                                 failed_gov_name, tz->governor->name, tz->type);
  81                         tz->governor = NULL;
  82                 }
  83         }
  84 }
  85
  86 /**
  87  * thermal_set_governor() - Switch to another governor
  88  * @tz:         a valid pointer to a struct thermal_zone_device
  89  * @new_gov:    pointer to the new governor
  90  *
  91  * Change the governor of thermal zone @tz.
  92  *
  93  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
  94  */
  95 static int thermal_set_governor(struct thermal_zone_device *tz,
  96                                 struct thermal_governor *new_gov)
  97 {
  98         int ret = 0;
  99
 100         if (tz->governor && tz->governor->unbind_from_tz)
 101                 tz->governor->unbind_from_tz(tz);
 102
 103         if (new_gov && new_gov->bind_to_tz) {
 104                 ret = new_gov->bind_to_tz(tz);
 105                 if (ret) {
 106                         bind_previous_governor(tz, new_gov->name);
 107
 108                         return ret;
 109                 }
 110         }
 111
 112         tz->governor = new_gov;
 113
 114         return ret;
 115 }
 116
 117 int thermal_register_governor(struct thermal_governor *governor)
 118 {
 119         int err;
 120         const char *name;
 121         struct thermal_zone_device *pos;
 122
 123         if (!governor)
 124                 return -EINVAL;
 125
 126         mutex_lock(&thermal_governor_lock);
 127
 128         err = -EBUSY;
 129         if (!__find_governor(governor->name)) {
 130                 bool match_default;
 131
 132                 err = 0;
 133                 list_add(&governor->governor_list, &thermal_governor_list);
 134                 match_default = !strncmp(governor->name,
 135                                          DEFAULT_THERMAL_GOVERNOR,
 136                                          THERMAL_NAME_LENGTH);
 137
 138                 if (!def_governor && match_default)
 139                         def_governor = governor;
 140         }
 141
 142         mutex_lock(&thermal_list_lock);
 143
 144         list_for_each_entry(pos, &thermal_tz_list, node) {
 145                 /*
 146                  * only thermal zones with specified tz->tzp->governor_name
 147                  * may run with tz->govenor unset
 148                  */
 149                 if (pos->governor)
 150                         continue;
 151
 152                 name = pos->tzp->governor_name;
 153
 154                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 155                         int ret;
 156
 157                         ret = thermal_set_governor(pos, governor);
 158                         if (ret)
 159                                 dev_err(&pos->device,
 160                                         "Failed to set governor %s for thermal zone %s: %d\n",
 161                                         governor->name, pos->type, ret);
 162                 }
 163         }
 164
 165         mutex_unlock(&thermal_list_lock);
 166         mutex_unlock(&thermal_governor_lock);
 167
 168         return err;
 169 }
 170
 171 void thermal_unregister_governor(struct thermal_governor *governor)
 172 {
 173         struct thermal_zone_device *pos;
 174
 175         if (!governor)
 176                 return;
 177
 178         mutex_lock(&thermal_governor_lock);
 179
 180         if (!__find_governor(governor->name))
 181                 goto exit;
 182
 183         mutex_lock(&thermal_list_lock);
 184
 185         list_for_each_entry(pos, &thermal_tz_list, node) {
 186                 if (!strncasecmp(pos->governor->name, governor->name,
 187                                  THERMAL_NAME_LENGTH))
 188                         thermal_set_governor(pos, NULL);
 189         }
 190
 191         mutex_unlock(&thermal_list_lock);
 192         list_del(&governor->governor_list);
 193 exit:
 194         mutex_unlock(&thermal_governor_lock);
 195 }
 196
 197 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 198                                    char *policy)
 199 {
 200         struct thermal_governor *gov;
 201         int ret = -EINVAL;
 202
 203         mutex_lock(&thermal_governor_lock);
 204         mutex_lock(&tz->lock);
 205
 206         if (!device_is_registered(&tz->device))
 207                 goto exit;
 208
 209         gov = __find_governor(strim(policy));
 210         if (!gov)
 211                 goto exit;
 212
 213         ret = thermal_set_governor(tz, gov);
 214
 215 exit:
 216         mutex_unlock(&tz->lock);
 217         mutex_unlock(&thermal_governor_lock);
 218
 219         thermal_notify_tz_gov_change(tz->id, policy);
 220
 221         return ret;
 222 }
 223
 224 int thermal_build_list_of_policies(char *buf)
 225 {
 226         struct thermal_governor *pos;
 227         ssize_t count = 0;
 228
 229         mutex_lock(&thermal_governor_lock);
 230
 231         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 232                 count += sysfs_emit_at(buf, count, "%s ", pos->name);
 233         }
 234         count += sysfs_emit_at(buf, count, "\n");
 235
 236         mutex_unlock(&thermal_governor_lock);
 237
 238         return count;
 239 }
 240
 241 static void __init thermal_unregister_governors(void)
 242 {
 243         struct thermal_governor **governor;
 244
 245         for_each_governor_table(governor)
 246                 thermal_unregister_governor(*governor);
 247 }
 248
 249 static int __init thermal_register_governors(void)
 250 {
 251         int ret = 0;
 252         struct thermal_governor **governor;
 253
 254         for_each_governor_table(governor) {
 255                 ret = thermal_register_governor(*governor);
 256                 if (ret) {
 257                         pr_err("Failed to register governor: '%s'",
 258                                (*governor)->name);
 259                         break;
 260                 }
 261
 262                 pr_info("Registered thermal governor '%s'",
 263                         (*governor)->name);
 264         }
 265
 266         if (ret) {
 267                 struct thermal_governor **gov;
 268
 269                 for_each_governor_table(gov) {
 270                         if (gov == governor)
 271                                 break;
 272                         thermal_unregister_governor(*gov);
 273                 }
 274         }
 275
 276         return ret;
 277 }
 278
 279 /*
 280  * Zone update section: main control loop applied to each zone while monitoring
 281  *
 282  * in polling mode. The monitoring is done using a workqueue.
 283  * Same update may be done on a zone by calling thermal_zone_device_update().
 284  *
 285  * An update means:
 286  * - Non-critical trips will invoke the governor responsible for that zone;
 287  * - Hot trips will produce a notification to userspace;
 288  * - Critical trip point will cause a system shutdown.
 289  */
 290 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 291                                             unsigned long delay)
 292 {
 293         if (delay)
 294                 mod_delayed_work(system_freezable_power_efficient_wq,
 295                                  &tz->poll_queue, delay);
 296         else
 297                 cancel_delayed_work(&tz->poll_queue);
 298 }
 299
 300 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 301 {
 302         if (tz->mode != THERMAL_DEVICE_ENABLED)
 303                 thermal_zone_device_set_polling(tz, 0);
 304         else if (tz->passive)
 305                 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
 306         else if (tz->polling_delay_jiffies)
 307                 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
 308 }
 309
 310 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
 311 {
 312         tz->governor ? tz->governor->throttle(tz, trip) :
 313                        def_governor->throttle(tz, trip);
 314 }
 315
 316 void thermal_zone_device_critical(struct thermal_zone_device *tz)
 317 {
 318         /*
 319          * poweroff_delay_ms must be a carefully profiled positive value.
 320          * Its a must for forced_emergency_poweroff_work to be scheduled.
 321          */
 322         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 323
 324         dev_emerg(&tz->device, "%s: critical temperature reached, "
 325                   "shutting down\n", tz->type);
 326
 327         hw_protection_shutdown("Temperature too high", poweroff_delay_ms);
 328 }
 329 EXPORT_SYMBOL(thermal_zone_device_critical);
 330
 331 static void handle_critical_trips(struct thermal_zone_device *tz,
 332                                   int trip, int trip_temp, enum thermal_trip_type trip_type)
 333 {
 334         /* If we have not crossed the trip_temp, we do not care. */
 335         if (trip_temp <= 0 || tz->temperature < trip_temp)
 336                 return;
 337
 338         trace_thermal_zone_trip(tz, trip, trip_type);
 339
 340         if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
 341                 tz->ops->hot(tz);
 342         else if (trip_type == THERMAL_TRIP_CRITICAL)
 343                 tz->ops->critical(tz);
 344 }
 345
 346 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip_id)
 347 {
 348         struct thermal_trip trip;
 349
 350         /* Ignore disabled trip points */
 351         if (test_bit(trip_id, &tz->trips_disabled))
 352                 return;
 353
 354         __thermal_zone_get_trip(tz, trip_id, &trip);
 355
 356         if (tz->last_temperature != THERMAL_TEMP_INVALID) {
 357                 if (tz->last_temperature < trip.temperature &&
 358                     tz->temperature >= trip.temperature)
 359                         thermal_notify_tz_trip_up(tz->id, trip_id,
 360                                                   tz->temperature);
 361                 if (tz->last_temperature >= trip.temperature &&
 362                     tz->temperature < (trip.temperature - trip.hysteresis))
 363                         thermal_notify_tz_trip_down(tz->id, trip_id,
 364                                                     tz->temperature);
 365         }
 366
 367         if (trip.type == THERMAL_TRIP_CRITICAL || trip.type == THERMAL_TRIP_HOT)
 368                 handle_critical_trips(tz, trip_id, trip.temperature, trip.type);
 369         else
 370                 handle_non_critical_trips(tz, trip_id);
 371 }
 372
 373 static void update_temperature(struct thermal_zone_device *tz)
 374 {
 375         int temp, ret;
 376
 377         ret = __thermal_zone_get_temp(tz, &temp);
 378         if (ret) {
 379                 if (ret != -EAGAIN)
 380                         dev_warn(&tz->device,
 381                                  "failed to read out thermal zone (%d)\n",
 382                                  ret);
 383                 return;
 384         }
 385
 386         tz->last_temperature = tz->temperature;
 387         tz->temperature = temp;
 388
 389         trace_thermal_temperature(tz);
 390
 391         thermal_genl_sampling_temp(tz->id, temp);
 392 }
 393
 394 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 395 {
 396         struct thermal_instance *pos;
 397         tz->temperature = THERMAL_TEMP_INVALID;
 398         tz->prev_low_trip = -INT_MAX;
 399         tz->prev_high_trip = INT_MAX;
 400         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 401                 pos->initialized = false;
 402 }
 403
 404 void __thermal_zone_device_update(struct thermal_zone_device *tz,
 405                                   enum thermal_notify_event event)
 406 {
 407         int count;
 408
 409         if (atomic_read(&in_suspend))
 410                 return;
 411
 412         if (WARN_ONCE(!tz->ops->get_temp,
 413                       "'%s' must not be called without 'get_temp' ops set\n",
 414                       __func__))
 415                 return;
 416
 417         if (!thermal_zone_device_is_enabled(tz))
 418                 return;
 419
 420         update_temperature(tz);
 421
 422         __thermal_zone_set_trips(tz);
 423
 424         tz->notify_event = event;
 425
 426         for (count = 0; count < tz->num_trips; count++)
 427                 handle_thermal_trip(tz, count);
 428
 429         monitor_thermal_zone(tz);
 430 }
 431
 432 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
 433                                         enum thermal_device_mode mode)
 434 {
 435         int ret = 0;
 436
 437         mutex_lock(&tz->lock);
 438
 439         /* do nothing if mode isn't changing */
 440         if (mode == tz->mode) {
 441                 mutex_unlock(&tz->lock);
 442
 443                 return ret;
 444         }
 445
 446         if (!device_is_registered(&tz->device)) {
 447                 mutex_unlock(&tz->lock);
 448
 449                 return -ENODEV;
 450         }
 451
 452         if (tz->ops->change_mode)
 453                 ret = tz->ops->change_mode(tz, mode);
 454
 455         if (!ret)
 456                 tz->mode = mode;
 457
 458         __thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 459
 460         mutex_unlock(&tz->lock);
 461
 462         if (mode == THERMAL_DEVICE_ENABLED)
 463                 thermal_notify_tz_enable(tz->id);
 464         else
 465                 thermal_notify_tz_disable(tz->id);
 466
 467         return ret;
 468 }
 469
 470 int thermal_zone_device_enable(struct thermal_zone_device *tz)
 471 {
 472         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
 473 }
 474 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
 475
 476 int thermal_zone_device_disable(struct thermal_zone_device *tz)
 477 {
 478         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
 479 }
 480 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
 481
 482 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
 483 {
 484         lockdep_assert_held(&tz->lock);
 485
 486         return tz->mode == THERMAL_DEVICE_ENABLED;
 487 }
 488
 489 void thermal_zone_device_update(struct thermal_zone_device *tz,
 490                                 enum thermal_notify_event event)
 491 {
 492         mutex_lock(&tz->lock);
 493         if (device_is_registered(&tz->device))
 494                 __thermal_zone_device_update(tz, event);
 495         mutex_unlock(&tz->lock);
 496 }
 497 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 498
 499 static void thermal_zone_device_check(struct work_struct *work)
 500 {
 501         struct thermal_zone_device *tz = container_of(work, struct
 502                                                       thermal_zone_device,
 503                                                       poll_queue.work);
 504         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 505 }
 506
 507 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
 508                               void *data)
 509 {
 510         struct thermal_governor *gov;
 511         int ret = 0;
 512
 513         mutex_lock(&thermal_governor_lock);
 514         list_for_each_entry(gov, &thermal_governor_list, governor_list) {
 515                 ret = cb(gov, data);
 516                 if (ret)
 517                         break;
 518         }
 519         mutex_unlock(&thermal_governor_lock);
 520
 521         return ret;
 522 }
 523
 524 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
 525                                               void *), void *data)
 526 {
 527         struct thermal_cooling_device *cdev;
 528         int ret = 0;
 529
 530         mutex_lock(&thermal_list_lock);
 531         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 532                 ret = cb(cdev, data);
 533                 if (ret)
 534                         break;
 535         }
 536         mutex_unlock(&thermal_list_lock);
 537
 538         return ret;
 539 }
 540
 541 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
 542                           void *data)
 543 {
 544         struct thermal_zone_device *tz;
 545         int ret = 0;
 546
 547         mutex_lock(&thermal_list_lock);
 548         list_for_each_entry(tz, &thermal_tz_list, node) {
 549                 ret = cb(tz, data);
 550                 if (ret)
 551                         break;
 552         }
 553         mutex_unlock(&thermal_list_lock);
 554
 555         return ret;
 556 }
 557
 558 struct thermal_zone_device *thermal_zone_get_by_id(int id)
 559 {
 560         struct thermal_zone_device *tz, *match = NULL;
 561
 562         mutex_lock(&thermal_list_lock);
 563         list_for_each_entry(tz, &thermal_tz_list, node) {
 564                 if (tz->id == id) {
 565                         match = tz;
 566                         break;
 567                 }
 568         }
 569         mutex_unlock(&thermal_list_lock);
 570
 571         return match;
 572 }
 573
 574 /*
 575  * Device management section: cooling devices, zones devices, and binding
 576  *
 577  * Set of functions provided by the thermal core for:
 578  * - cooling devices lifecycle: registration, unregistration,
 579  *                              binding, and unbinding.
 580  * - thermal zone devices lifecycle: registration, unregistration,
 581  *                                   binding, and unbinding.
 582  */
 583
 584 /**
 585  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 586  * @tz:         pointer to struct thermal_zone_device
 587  * @trip:       indicates which trip point the cooling devices is
 588  *              associated with in this thermal zone.
 589  * @cdev:       pointer to struct thermal_cooling_device
 590  * @upper:      the Maximum cooling state for this trip point.
 591  *              THERMAL_NO_LIMIT means no upper limit,
 592  *              and the cooling device can be in max_state.
 593  * @lower:      the Minimum cooling state can be used for this trip point.
 594  *              THERMAL_NO_LIMIT means no lower limit,
 595  *              and the cooling device can be in cooling state 0.
 596  * @weight:     The weight of the cooling device to be bound to the
 597  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 598  *              default value
 599  *
 600  * This interface function bind a thermal cooling device to the certain trip
 601  * point of a thermal zone device.
 602  * This function is usually called in the thermal zone device .bind callback.
 603  *
 604  * Return: 0 on success, the proper error value otherwise.
 605  */
 606 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 607                                      int trip,
 608                                      struct thermal_cooling_device *cdev,
 609                                      unsigned long upper, unsigned long lower,
 610                                      unsigned int weight)
 611 {
 612         struct thermal_instance *dev;
 613         struct thermal_instance *pos;
 614         struct thermal_zone_device *pos1;
 615         struct thermal_cooling_device *pos2;
 616         int result;
 617
 618         if (trip >= tz->num_trips || trip < 0)
 619                 return -EINVAL;
 620
 621         list_for_each_entry(pos1, &thermal_tz_list, node) {
 622                 if (pos1 == tz)
 623                         break;
 624         }
 625         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 626                 if (pos2 == cdev)
 627                         break;
 628         }
 629
 630         if (tz != pos1 || cdev != pos2)
 631                 return -EINVAL;
 632
 633         /* lower default 0, upper default max_state */
 634         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 635         upper = upper == THERMAL_NO_LIMIT ? cdev->max_state : upper;
 636
 637         if (lower > upper || upper > cdev->max_state)
 638                 return -EINVAL;
 639
 640         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 641         if (!dev)
 642                 return -ENOMEM;
 643         dev->tz = tz;
 644         dev->cdev = cdev;
 645         dev->trip = trip;
 646         dev->upper = upper;
 647         dev->lower = lower;
 648         dev->target = THERMAL_NO_TARGET;
 649         dev->weight = weight;
 650
 651         result = ida_alloc(&tz->ida, GFP_KERNEL);
 652         if (result < 0)
 653                 goto free_mem;
 654
 655         dev->id = result;
 656         sprintf(dev->name, "cdev%d", dev->id);
 657         result =
 658             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 659         if (result)
 660                 goto release_ida;
 661
 662         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 663         sysfs_attr_init(&dev->attr.attr);
 664         dev->attr.attr.name = dev->attr_name;
 665         dev->attr.attr.mode = 0444;
 666         dev->attr.show = trip_point_show;
 667         result = device_create_file(&tz->device, &dev->attr);
 668         if (result)
 669                 goto remove_symbol_link;
 670
 671         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 672         sysfs_attr_init(&dev->weight_attr.attr);
 673         dev->weight_attr.attr.name = dev->weight_attr_name;
 674         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 675         dev->weight_attr.show = weight_show;
 676         dev->weight_attr.store = weight_store;
 677         result = device_create_file(&tz->device, &dev->weight_attr);
 678         if (result)
 679                 goto remove_trip_file;
 680
 681         mutex_lock(&tz->lock);
 682         mutex_lock(&cdev->lock);
 683         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 684                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 685                         result = -EEXIST;
 686                         break;
 687                 }
 688         if (!result) {
 689                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 690                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 691                 atomic_set(&tz->need_update, 1);
 692         }
 693         mutex_unlock(&cdev->lock);
 694         mutex_unlock(&tz->lock);
 695
 696         if (!result)
 697                 return 0;
 698
 699         device_remove_file(&tz->device, &dev->weight_attr);
 700 remove_trip_file:
 701         device_remove_file(&tz->device, &dev->attr);
 702 remove_symbol_link:
 703         sysfs_remove_link(&tz->device.kobj, dev->name);
 704 release_ida:
 705         ida_free(&tz->ida, dev->id);
 706 free_mem:
 707         kfree(dev);
 708         return result;
 709 }
 710 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 711
 712 /**
 713  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 714  *                                        thermal zone.
 715  * @tz:         pointer to a struct thermal_zone_device.
 716  * @trip:       indicates which trip point the cooling devices is
 717  *              associated with in this thermal zone.
 718  * @cdev:       pointer to a struct thermal_cooling_device.
 719  *
 720  * This interface function unbind a thermal cooling device from the certain
 721  * trip point of a thermal zone device.
 722  * This function is usually called in the thermal zone device .unbind callback.
 723  *
 724  * Return: 0 on success, the proper error value otherwise.
 725  */
 726 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 727                                        int trip,
 728                                        struct thermal_cooling_device *cdev)
 729 {
 730         struct thermal_instance *pos, *next;
 731
 732         mutex_lock(&tz->lock);
 733         mutex_lock(&cdev->lock);
 734         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 735                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 736                         list_del(&pos->tz_node);
 737                         list_del(&pos->cdev_node);
 738                         mutex_unlock(&cdev->lock);
 739                         mutex_unlock(&tz->lock);
 740                         goto unbind;
 741                 }
 742         }
 743         mutex_unlock(&cdev->lock);
 744         mutex_unlock(&tz->lock);
 745
 746         return -ENODEV;
 747
 748 unbind:
 749         device_remove_file(&tz->device, &pos->weight_attr);
 750         device_remove_file(&tz->device, &pos->attr);
 751         sysfs_remove_link(&tz->device.kobj, pos->name);
 752         ida_free(&tz->ida, pos->id);
 753         kfree(pos);
 754         return 0;
 755 }
 756 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 757
 758 static void thermal_release(struct device *dev)
 759 {
 760         struct thermal_zone_device *tz;
 761         struct thermal_cooling_device *cdev;
 762
 763         if (!strncmp(dev_name(dev), "thermal_zone",
 764                      sizeof("thermal_zone") - 1)) {
 765                 tz = to_thermal_zone(dev);
 766                 thermal_zone_destroy_device_groups(tz);
 767                 mutex_destroy(&tz->lock);
 768                 kfree(tz);
 769         } else if (!strncmp(dev_name(dev), "cooling_device",
 770                             sizeof("cooling_device") - 1)) {
 771                 cdev = to_cooling_device(dev);
 772                 thermal_cooling_device_destroy_sysfs(cdev);
 773                 kfree(cdev->type);
 774                 ida_free(&thermal_cdev_ida, cdev->id);
 775                 kfree(cdev);
 776         }
 777 }
 778
 779 static struct class *thermal_class;
 780
 781 static inline
 782 void print_bind_err_msg(struct thermal_zone_device *tz,
 783                         struct thermal_cooling_device *cdev, int ret)
 784 {
 785         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 786                 tz->type, cdev->type, ret);
 787 }
 788
 789 static void __bind(struct thermal_zone_device *tz, int mask,
 790                    struct thermal_cooling_device *cdev,
 791                    unsigned long *limits,
 792                    unsigned int weight)
 793 {
 794         int i, ret;
 795
 796         for (i = 0; i < tz->num_trips; i++) {
 797                 if (mask & (1 << i)) {
 798                         unsigned long upper, lower;
 799
 800                         upper = THERMAL_NO_LIMIT;
 801                         lower = THERMAL_NO_LIMIT;
 802                         if (limits) {
 803                                 lower = limits[i * 2];
 804                                 upper = limits[i * 2 + 1];
 805                         }
 806                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 807                                                                upper, lower,
 808                                                                weight);
 809                         if (ret)
 810                                 print_bind_err_msg(tz, cdev, ret);
 811                 }
 812         }
 813 }
 814
 815 static void bind_cdev(struct thermal_cooling_device *cdev)
 816 {
 817         int i, ret;
 818         const struct thermal_zone_params *tzp;
 819         struct thermal_zone_device *pos = NULL;
 820
 821         mutex_lock(&thermal_list_lock);
 822
 823         list_for_each_entry(pos, &thermal_tz_list, node) {
 824                 if (!pos->tzp && !pos->ops->bind)
 825                         continue;
 826
 827                 if (pos->ops->bind) {
 828                         ret = pos->ops->bind(pos, cdev);
 829                         if (ret)
 830                                 print_bind_err_msg(pos, cdev, ret);
 831                         continue;
 832                 }
 833
 834                 tzp = pos->tzp;
 835                 if (!tzp || !tzp->tbp)
 836                         continue;
 837
 838                 for (i = 0; i < tzp->num_tbps; i++) {
 839                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 840                                 continue;
 841                         if (tzp->tbp[i].match(pos, cdev))
 842                                 continue;
 843                         tzp->tbp[i].cdev = cdev;
 844                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 845                                tzp->tbp[i].binding_limits,
 846                                tzp->tbp[i].weight);
 847                 }
 848         }
 849
 850         mutex_unlock(&thermal_list_lock);
 851 }
 852
 853 /**
 854  * __thermal_cooling_device_register() - register a new thermal cooling device
 855  * @np:         a pointer to a device tree node.
 856  * @type:       the thermal cooling device type.
 857  * @devdata:    device private data.
 858  * @ops:                standard thermal cooling devices callbacks.
 859  *
 860  * This interface function adds a new thermal cooling device (fan/processor/...)
 861  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 862  * to all the thermal zone devices registered at the same time.
 863  * It also gives the opportunity to link the cooling device to a device tree
 864  * node, so that it can be bound to a thermal zone created out of device tree.
 865  *
 866  * Return: a pointer to the created struct thermal_cooling_device or an
 867  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 868  */
 869 static struct thermal_cooling_device *
 870 __thermal_cooling_device_register(struct device_node *np,
 871                                   const char *type, void *devdata,
 872                                   const struct thermal_cooling_device_ops *ops)
 873 {
 874         struct thermal_cooling_device *cdev;
 875         struct thermal_zone_device *pos = NULL;
 876         int id, ret;
 877
 878         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 879             !ops->set_cur_state)
 880                 return ERR_PTR(-EINVAL);
 881
 882         if (!thermal_class)
 883                 return ERR_PTR(-ENODEV);
 884
 885         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 886         if (!cdev)
 887                 return ERR_PTR(-ENOMEM);
 888
 889         ret = ida_alloc(&thermal_cdev_ida, GFP_KERNEL);
 890         if (ret < 0)
 891                 goto out_kfree_cdev;
 892         cdev->id = ret;
 893         id = ret;
 894
 895         cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
 896         if (!cdev->type) {
 897                 ret = -ENOMEM;
 898                 goto out_ida_remove;
 899         }
 900
 901         mutex_init(&cdev->lock);
 902         INIT_LIST_HEAD(&cdev->thermal_instances);
 903         cdev->np = np;
 904         cdev->ops = ops;
 905         cdev->updated = false;
 906         cdev->device.class = thermal_class;
 907         cdev->devdata = devdata;
 908
 909         ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
 910         if (ret)
 911                 goto out_cdev_type;
 912
 913         thermal_cooling_device_setup_sysfs(cdev);
 914
 915         ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 916         if (ret)
 917                 goto out_cooling_dev;
 918
 919         ret = device_register(&cdev->device);
 920         if (ret) {
 921                 /* thermal_release() handles rest of the cleanup */
 922                 put_device(&cdev->device);
 923                 return ERR_PTR(ret);
 924         }
 925
 926         /* Add 'this' new cdev to the global cdev list */
 927         mutex_lock(&thermal_list_lock);
 928         list_add(&cdev->node, &thermal_cdev_list);
 929         mutex_unlock(&thermal_list_lock);
 930
 931         /* Update binding information for 'this' new cdev */
 932         bind_cdev(cdev);
 933
 934         mutex_lock(&thermal_list_lock);
 935         list_for_each_entry(pos, &thermal_tz_list, node)
 936                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
 937                         thermal_zone_device_update(pos,
 938                                                    THERMAL_EVENT_UNSPECIFIED);
 939         mutex_unlock(&thermal_list_lock);
 940
 941         return cdev;
 942
 943 out_cooling_dev:
 944         thermal_cooling_device_destroy_sysfs(cdev);
 945 out_cdev_type:
 946         kfree(cdev->type);
 947 out_ida_remove:
 948         ida_free(&thermal_cdev_ida, id);
 949 out_kfree_cdev:
 950         kfree(cdev);
 951         return ERR_PTR(ret);
 952 }
 953
 954 /**
 955  * thermal_cooling_device_register() - register a new thermal cooling device
 956  * @type:       the thermal cooling device type.
 957  * @devdata:    device private data.
 958  * @ops:                standard thermal cooling devices callbacks.
 959  *
 960  * This interface function adds a new thermal cooling device (fan/processor/...)
 961  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 962  * to all the thermal zone devices registered at the same time.
 963  *
 964  * Return: a pointer to the created struct thermal_cooling_device or an
 965  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 966  */
 967 struct thermal_cooling_device *
 968 thermal_cooling_device_register(const char *type, void *devdata,
 969                                 const struct thermal_cooling_device_ops *ops)
 970 {
 971         return __thermal_cooling_device_register(NULL, type, devdata, ops);
 972 }
 973 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
 974
 975 /**
 976  * thermal_of_cooling_device_register() - register an OF thermal cooling device
 977  * @np:         a pointer to a device tree node.
 978  * @type:       the thermal cooling device type.
 979  * @devdata:    device private data.
 980  * @ops:                standard thermal cooling devices callbacks.
 981  *
 982  * This function will register a cooling device with device tree node reference.
 983  * This interface function adds a new thermal cooling device (fan/processor/...)
 984  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 985  * to all the thermal zone devices registered at the same time.
 986  *
 987  * Return: a pointer to the created struct thermal_cooling_device or an
 988  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 989  */
 990 struct thermal_cooling_device *
 991 thermal_of_cooling_device_register(struct device_node *np,
 992                                    const char *type, void *devdata,
 993                                    const struct thermal_cooling_device_ops *ops)
 994 {
 995         return __thermal_cooling_device_register(np, type, devdata, ops);
 996 }
 997 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
 998
 999 static void thermal_cooling_device_release(struct device *dev, void *res)
1000 {
1001         thermal_cooling_device_unregister(
1002                                 *(struct thermal_cooling_device **)res);
1003 }
1004
1005 /**
1006  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1007  *                                             device
1008  * @dev:        a valid struct device pointer of a sensor device.
1009  * @np:         a pointer to a device tree node.
1010  * @type:       the thermal cooling device type.
1011  * @devdata:    device private data.
1012  * @ops:        standard thermal cooling devices callbacks.
1013  *
1014  * This function will register a cooling device with device tree node reference.
1015  * This interface function adds a new thermal cooling device (fan/processor/...)
1016  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1017  * to all the thermal zone devices registered at the same time.
1018  *
1019  * Return: a pointer to the created struct thermal_cooling_device or an
1020  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1021  */
1022 struct thermal_cooling_device *
1023 devm_thermal_of_cooling_device_register(struct device *dev,
1024                                 struct device_node *np,
1025                                 char *type, void *devdata,
1026                                 const struct thermal_cooling_device_ops *ops)
1027 {
1028         struct thermal_cooling_device **ptr, *tcd;
1029
1030         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1031                            GFP_KERNEL);
1032         if (!ptr)
1033                 return ERR_PTR(-ENOMEM);
1034
1035         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1036         if (IS_ERR(tcd)) {
1037                 devres_free(ptr);
1038                 return tcd;
1039         }
1040
1041         *ptr = tcd;
1042         devres_add(dev, ptr);
1043
1044         return tcd;
1045 }
1046 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1047
1048 static void __unbind(struct thermal_zone_device *tz, int mask,
1049                      struct thermal_cooling_device *cdev)
1050 {
1051         int i;
1052
1053         for (i = 0; i < tz->num_trips; i++)
1054                 if (mask & (1 << i))
1055                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1056 }
1057
1058 /**
1059  * thermal_cooling_device_unregister - removes a thermal cooling device
1060  * @cdev:       the thermal cooling device to remove.
1061  *
1062  * thermal_cooling_device_unregister() must be called when a registered
1063  * thermal cooling device is no longer needed.
1064  */
1065 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1066 {
1067         int i;
1068         const struct thermal_zone_params *tzp;
1069         struct thermal_zone_device *tz;
1070         struct thermal_cooling_device *pos = NULL;
1071
1072         if (!cdev)
1073                 return;
1074
1075         mutex_lock(&thermal_list_lock);
1076         list_for_each_entry(pos, &thermal_cdev_list, node)
1077                 if (pos == cdev)
1078                         break;
1079         if (pos != cdev) {
1080                 /* thermal cooling device not found */
1081                 mutex_unlock(&thermal_list_lock);
1082                 return;
1083         }
1084         list_del(&cdev->node);
1085
1086         /* Unbind all thermal zones associated with 'this' cdev */
1087         list_for_each_entry(tz, &thermal_tz_list, node) {
1088                 if (tz->ops->unbind) {
1089                         tz->ops->unbind(tz, cdev);
1090                         continue;
1091                 }
1092
1093                 if (!tz->tzp || !tz->tzp->tbp)
1094                         continue;
1095
1096                 tzp = tz->tzp;
1097                 for (i = 0; i < tzp->num_tbps; i++) {
1098                         if (tzp->tbp[i].cdev == cdev) {
1099                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1100                                 tzp->tbp[i].cdev = NULL;
1101                         }
1102                 }
1103         }
1104
1105         mutex_unlock(&thermal_list_lock);
1106
1107         device_unregister(&cdev->device);
1108 }
1109 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1110
1111 static void bind_tz(struct thermal_zone_device *tz)
1112 {
1113         int i, ret;
1114         struct thermal_cooling_device *pos = NULL;
1115         const struct thermal_zone_params *tzp = tz->tzp;
1116
1117         if (!tzp && !tz->ops->bind)
1118                 return;
1119
1120         mutex_lock(&thermal_list_lock);
1121
1122         /* If there is ops->bind, try to use ops->bind */
1123         if (tz->ops->bind) {
1124                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1125                         ret = tz->ops->bind(tz, pos);
1126                         if (ret)
1127                                 print_bind_err_msg(tz, pos, ret);
1128                 }
1129                 goto exit;
1130         }
1131
1132         if (!tzp || !tzp->tbp)
1133                 goto exit;
1134
1135         list_for_each_entry(pos, &thermal_cdev_list, node) {
1136                 for (i = 0; i < tzp->num_tbps; i++) {
1137                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1138                                 continue;
1139                         if (tzp->tbp[i].match(tz, pos))
1140                                 continue;
1141                         tzp->tbp[i].cdev = pos;
1142                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1143                                tzp->tbp[i].binding_limits,
1144                                tzp->tbp[i].weight);
1145                 }
1146         }
1147 exit:
1148         mutex_unlock(&thermal_list_lock);
1149 }
1150
1151 static void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms)
1152 {
1153         *delay_jiffies = msecs_to_jiffies(delay_ms);
1154         if (delay_ms > 1000)
1155                 *delay_jiffies = round_jiffies(*delay_jiffies);
1156 }
1157
1158 int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp)
1159 {
1160         int i, ret = -EINVAL;
1161
1162         if (tz->ops->get_crit_temp)
1163                 return tz->ops->get_crit_temp(tz, temp);
1164
1165         if (!tz->trips)
1166                 return -EINVAL;
1167
1168         mutex_lock(&tz->lock);
1169
1170         for (i = 0; i < tz->num_trips; i++) {
1171                 if (tz->trips[i].type == THERMAL_TRIP_CRITICAL) {
1172                         *temp = tz->trips[i].temperature;
1173                         ret = 0;
1174                         break;
1175                 }
1176         }
1177
1178         mutex_unlock(&tz->lock);
1179
1180         return ret;
1181 }
1182 EXPORT_SYMBOL_GPL(thermal_zone_get_crit_temp);
1183
1184 /**
1185  * thermal_zone_device_register_with_trips() - register a new thermal zone device
1186  * @type:       the thermal zone device type
1187  * @trips:      a pointer to an array of thermal trips
1188  * @num_trips:  the number of trip points the thermal zone support
1189  * @mask:       a bit string indicating the writeablility of trip points
1190  * @devdata:    private device data
1191  * @ops:        standard thermal zone device callbacks
1192  * @tzp:        thermal zone platform parameters
1193  * @passive_delay: number of milliseconds to wait between polls when
1194  *                 performing passive cooling
1195  * @polling_delay: number of milliseconds to wait between polls when checking
1196  *                 whether trip points have been crossed (0 for interrupt
1197  *                 driven systems)
1198  *
1199  * This interface function adds a new thermal zone device (sensor) to
1200  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1201  * thermal cooling devices registered at the same time.
1202  * thermal_zone_device_unregister() must be called when the device is no
1203  * longer needed. The passive cooling depends on the .get_trend() return value.
1204  *
1205  * Return: a pointer to the created struct thermal_zone_device or an
1206  * in case of error, an ERR_PTR. Caller must check return value with
1207  * IS_ERR*() helpers.
1208  */
1209 struct thermal_zone_device *
1210 thermal_zone_device_register_with_trips(const char *type, struct thermal_trip *trips, int num_trips, int mask,
1211                                         void *devdata, struct thermal_zone_device_ops *ops,
1212                                         struct thermal_zone_params *tzp, int passive_delay,
1213                                         int polling_delay)
1214 {
1215         struct thermal_zone_device *tz;
1216         int id;
1217         int result;
1218         int count;
1219         struct thermal_governor *governor;
1220
1221         if (!type || strlen(type) == 0) {
1222                 pr_err("No thermal zone type defined\n");
1223                 return ERR_PTR(-EINVAL);
1224         }
1225
1226         if (strlen(type) >= THERMAL_NAME_LENGTH) {
1227                 pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1228                        type, THERMAL_NAME_LENGTH);
1229                 return ERR_PTR(-EINVAL);
1230         }
1231
1232         /*
1233          * Max trip count can't exceed 31 as the "mask >> num_trips" condition.
1234          * For example, shifting by 32 will result in compiler warning:
1235          * warning: right shift count >= width of type [-Wshift-count- overflow]
1236          *
1237          * Also "mask >> num_trips" will always be true with 32 bit shift.
1238          * E.g. mask = 0x80000000 for trip id 31 to be RW. Then
1239          * mask >> 32 = 0x80000000
1240          * This will result in failure for the below condition.
1241          *
1242          * Check will be true when the bit 31 of the mask is set.
1243          * 32 bit shift will cause overflow of 4 byte integer.
1244          */
1245         if (num_trips > (BITS_PER_TYPE(int) - 1) || num_trips < 0 || mask >> num_trips) {
1246                 pr_err("Incorrect number of thermal trips\n");
1247                 return ERR_PTR(-EINVAL);
1248         }
1249
1250         if (!ops) {
1251                 pr_err("Thermal zone device ops not defined\n");
1252                 return ERR_PTR(-EINVAL);
1253         }
1254
1255         if (num_trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp) && !trips)
1256                 return ERR_PTR(-EINVAL);
1257
1258         if (!thermal_class)
1259                 return ERR_PTR(-ENODEV);
1260
1261         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1262         if (!tz)
1263                 return ERR_PTR(-ENOMEM);
1264
1265         INIT_LIST_HEAD(&tz->thermal_instances);
1266         ida_init(&tz->ida);
1267         mutex_init(&tz->lock);
1268         id = ida_alloc(&thermal_tz_ida, GFP_KERNEL);
1269         if (id < 0) {
1270                 result = id;
1271                 goto free_tz;
1272         }
1273
1274         tz->id = id;
1275         strscpy(tz->type, type, sizeof(tz->type));
1276
1277         if (!ops->critical)
1278                 ops->critical = thermal_zone_device_critical;
1279
1280         tz->ops = ops;
1281         tz->tzp = tzp;
1282         tz->device.class = thermal_class;
1283         tz->devdata = devdata;
1284         tz->trips = trips;
1285         tz->num_trips = num_trips;
1286
1287         thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1288         thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1289
1290         /* sys I/F */
1291         /* Add nodes that are always present via .groups */
1292         result = thermal_zone_create_device_groups(tz, mask);
1293         if (result)
1294                 goto remove_id;
1295
1296         /* A new thermal zone needs to be updated anyway. */
1297         atomic_set(&tz->need_update, 1);
1298
1299         result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1300         if (result) {
1301                 thermal_zone_destroy_device_groups(tz);
1302                 goto remove_id;
1303         }
1304         result = device_register(&tz->device);
1305         if (result)
1306                 goto release_device;
1307
1308         for (count = 0; count < num_trips; count++) {
1309                 struct thermal_trip trip;
1310
1311                 result = thermal_zone_get_trip(tz, count, &trip);
1312                 if (result)
1313                         set_bit(count, &tz->trips_disabled);
1314         }
1315
1316         /* Update 'this' zone's governor information */
1317         mutex_lock(&thermal_governor_lock);
1318
1319         if (tz->tzp)
1320                 governor = __find_governor(tz->tzp->governor_name);
1321         else
1322                 governor = def_governor;
1323
1324         result = thermal_set_governor(tz, governor);
1325         if (result) {
1326                 mutex_unlock(&thermal_governor_lock);
1327                 goto unregister;
1328         }
1329
1330         mutex_unlock(&thermal_governor_lock);
1331
1332         if (!tz->tzp || !tz->tzp->no_hwmon) {
1333                 result = thermal_add_hwmon_sysfs(tz);
1334                 if (result)
1335                         goto unregister;
1336         }
1337
1338         mutex_lock(&thermal_list_lock);
1339         list_add_tail(&tz->node, &thermal_tz_list);
1340         mutex_unlock(&thermal_list_lock);
1341
1342         /* Bind cooling devices for this zone */
1343         bind_tz(tz);
1344
1345         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1346
1347         thermal_zone_device_init(tz);
1348         /* Update the new thermal zone and mark it as already updated. */
1349         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1350                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1351
1352         thermal_notify_tz_create(tz->id, tz->type);
1353
1354         return tz;
1355
1356 unregister:
1357         device_del(&tz->device);
1358 release_device:
1359         put_device(&tz->device);
1360         tz = NULL;
1361 remove_id:
1362         ida_free(&thermal_tz_ida, id);
1363 free_tz:
1364         kfree(tz);
1365         return ERR_PTR(result);
1366 }
1367 EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1368
1369 struct thermal_zone_device *thermal_zone_device_register(const char *type, int ntrips, int mask,
1370                                                          void *devdata, struct thermal_zone_device_ops *ops,
1371                                                          struct thermal_zone_params *tzp, int passive_delay,
1372                                                          int polling_delay)
1373 {
1374         return thermal_zone_device_register_with_trips(type, NULL, ntrips, mask,
1375                                                        devdata, ops, tzp,
1376                                                        passive_delay, polling_delay);
1377 }
1378 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1379
1380 /**
1381  * thermal_zone_device_unregister - removes the registered thermal zone device
1382  * @tz: the thermal zone device to remove
1383  */
1384 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1385 {
1386         int i, tz_id;
1387         const struct thermal_zone_params *tzp;
1388         struct thermal_cooling_device *cdev;
1389         struct thermal_zone_device *pos = NULL;
1390
1391         if (!tz)
1392                 return;
1393
1394         tzp = tz->tzp;
1395         tz_id = tz->id;
1396
1397         mutex_lock(&thermal_list_lock);
1398         list_for_each_entry(pos, &thermal_tz_list, node)
1399                 if (pos == tz)
1400                         break;
1401         if (pos != tz) {
1402                 /* thermal zone device not found */
1403                 mutex_unlock(&thermal_list_lock);
1404                 return;
1405         }
1406         list_del(&tz->node);
1407
1408         /* Unbind all cdevs associated with 'this' thermal zone */
1409         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1410                 if (tz->ops->unbind) {
1411                         tz->ops->unbind(tz, cdev);
1412                         continue;
1413                 }
1414
1415                 if (!tzp || !tzp->tbp)
1416                         break;
1417
1418                 for (i = 0; i < tzp->num_tbps; i++) {
1419                         if (tzp->tbp[i].cdev == cdev) {
1420                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1421                                 tzp->tbp[i].cdev = NULL;
1422                         }
1423                 }
1424         }
1425
1426         mutex_unlock(&thermal_list_lock);
1427
1428         cancel_delayed_work_sync(&tz->poll_queue);
1429
1430         thermal_set_governor(tz, NULL);
1431
1432         thermal_remove_hwmon_sysfs(tz);
1433         ida_free(&thermal_tz_ida, tz->id);
1434         ida_destroy(&tz->ida);
1435
1436         mutex_lock(&tz->lock);
1437         device_del(&tz->device);
1438         mutex_unlock(&tz->lock);
1439
1440         put_device(&tz->device);
1441
1442         thermal_notify_tz_delete(tz_id);
1443 }
1444 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1445
1446 /**
1447  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1448  * @name: thermal zone name to fetch the temperature
1449  *
1450  * When only one zone is found with the passed name, returns a reference to it.
1451  *
1452  * Return: On success returns a reference to an unique thermal zone with
1453  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1454  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1455  */
1456 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1457 {
1458         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1459         unsigned int found = 0;
1460
1461         if (!name)
1462                 goto exit;
1463
1464         mutex_lock(&thermal_list_lock);
1465         list_for_each_entry(pos, &thermal_tz_list, node)
1466                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1467                         found++;
1468                         ref = pos;
1469                 }
1470         mutex_unlock(&thermal_list_lock);
1471
1472         /* nothing has been found, thus an error code for it */
1473         if (found == 0)
1474                 ref = ERR_PTR(-ENODEV);
1475         else if (found > 1)
1476         /* Success only when an unique zone is found */
1477                 ref = ERR_PTR(-EEXIST);
1478
1479 exit:
1480         return ref;
1481 }
1482 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1483
1484 static int thermal_pm_notify(struct notifier_block *nb,
1485                              unsigned long mode, void *_unused)
1486 {
1487         struct thermal_zone_device *tz;
1488
1489         switch (mode) {
1490         case PM_HIBERNATION_PREPARE:
1491         case PM_RESTORE_PREPARE:
1492         case PM_SUSPEND_PREPARE:
1493                 atomic_set(&in_suspend, 1);
1494                 break;
1495         case PM_POST_HIBERNATION:
1496         case PM_POST_RESTORE:
1497         case PM_POST_SUSPEND:
1498                 atomic_set(&in_suspend, 0);
1499                 list_for_each_entry(tz, &thermal_tz_list, node) {
1500                         thermal_zone_device_init(tz);
1501                         thermal_zone_device_update(tz,
1502                                                    THERMAL_EVENT_UNSPECIFIED);
1503                 }
1504                 break;
1505         default:
1506                 break;
1507         }
1508         return 0;
1509 }
1510
1511 static struct notifier_block thermal_pm_nb = {
1512         .notifier_call = thermal_pm_notify,
1513 };
1514
1515 static int __init thermal_init(void)
1516 {
1517         int result;
1518
1519         result = thermal_netlink_init();
1520         if (result)
1521                 goto error;
1522
1523         result = thermal_register_governors();
1524         if (result)
1525                 goto unregister_netlink;
1526
1527         thermal_class = kzalloc(sizeof(*thermal_class), GFP_KERNEL);
1528         if (!thermal_class) {
1529                 result = -ENOMEM;
1530                 goto unregister_governors;
1531         }
1532
1533         thermal_class->name = "thermal";
1534         thermal_class->dev_release = thermal_release;
1535
1536         result = class_register(thermal_class);
1537         if (result) {
1538                 kfree(thermal_class);
1539                 thermal_class = NULL;
1540                 goto unregister_governors;
1541         }
1542
1543         result = register_pm_notifier(&thermal_pm_nb);
1544         if (result)
1545                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1546                         result);
1547
1548         return 0;
1549
1550 unregister_governors:
1551         thermal_unregister_governors();
1552 unregister_netlink:
1553         thermal_netlink_exit();
1554 error:
1555         mutex_destroy(&thermal_list_lock);
1556         mutex_destroy(&thermal_governor_lock);
1557         return result;
1558 }
1559 postcore_initcall(thermal_init);