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 "thermal_trace.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 struct thermal_governor *def_governor;
  41
  42 /*
  43  * Governor section: set of functions to handle thermal governors
  44  *
  45  * Functions to help in the life cycle of thermal governors within
  46  * the thermal core and by the thermal governor code.
  47  */
  48
  49 static struct thermal_governor *__find_governor(const char *name)
  50 {
  51         struct thermal_governor *pos;
  52
  53         if (!name || !name[0])
  54                 return def_governor;
  55
  56         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  57                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  58                         return pos;
  59
  60         return NULL;
  61 }
  62
  63 /**
  64  * bind_previous_governor() - bind the previous governor of the thermal zone
  65  * @tz:         a valid pointer to a struct thermal_zone_device
  66  * @failed_gov_name:    the name of the governor that failed to register
  67  *
  68  * Register the previous governor of the thermal zone after a new
  69  * governor has failed to be bound.
  70  */
  71 static void bind_previous_governor(struct thermal_zone_device *tz,
  72                                    const char *failed_gov_name)
  73 {
  74         if (tz->governor && tz->governor->bind_to_tz) {
  75                 if (tz->governor->bind_to_tz(tz)) {
  76                         dev_err(&tz->device,
  77                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  78                                 failed_gov_name, tz->governor->name, tz->type);
  79                         tz->governor = NULL;
  80                 }
  81         }
  82 }
  83
  84 /**
  85  * thermal_set_governor() - Switch to another governor
  86  * @tz:         a valid pointer to a struct thermal_zone_device
  87  * @new_gov:    pointer to the new governor
  88  *
  89  * Change the governor of thermal zone @tz.
  90  *
  91  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
  92  */
  93 static int thermal_set_governor(struct thermal_zone_device *tz,
  94                                 struct thermal_governor *new_gov)
  95 {
  96         int ret = 0;
  97
  98         if (tz->governor && tz->governor->unbind_from_tz)
  99                 tz->governor->unbind_from_tz(tz);
 100
 101         if (new_gov && new_gov->bind_to_tz) {
 102                 ret = new_gov->bind_to_tz(tz);
 103                 if (ret) {
 104                         bind_previous_governor(tz, new_gov->name);
 105
 106                         return ret;
 107                 }
 108         }
 109
 110         tz->governor = new_gov;
 111
 112         return ret;
 113 }
 114
 115 int thermal_register_governor(struct thermal_governor *governor)
 116 {
 117         int err;
 118         const char *name;
 119         struct thermal_zone_device *pos;
 120
 121         if (!governor)
 122                 return -EINVAL;
 123
 124         mutex_lock(&thermal_governor_lock);
 125
 126         err = -EBUSY;
 127         if (!__find_governor(governor->name)) {
 128                 bool match_default;
 129
 130                 err = 0;
 131                 list_add(&governor->governor_list, &thermal_governor_list);
 132                 match_default = !strncmp(governor->name,
 133                                          DEFAULT_THERMAL_GOVERNOR,
 134                                          THERMAL_NAME_LENGTH);
 135
 136                 if (!def_governor && match_default)
 137                         def_governor = governor;
 138         }
 139
 140         mutex_lock(&thermal_list_lock);
 141
 142         list_for_each_entry(pos, &thermal_tz_list, node) {
 143                 /*
 144                  * only thermal zones with specified tz->tzp->governor_name
 145                  * may run with tz->govenor unset
 146                  */
 147                 if (pos->governor)
 148                         continue;
 149
 150                 name = pos->tzp->governor_name;
 151
 152                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 153                         int ret;
 154
 155                         ret = thermal_set_governor(pos, governor);
 156                         if (ret)
 157                                 dev_err(&pos->device,
 158                                         "Failed to set governor %s for thermal zone %s: %d\n",
 159                                         governor->name, pos->type, ret);
 160                 }
 161         }
 162
 163         mutex_unlock(&thermal_list_lock);
 164         mutex_unlock(&thermal_governor_lock);
 165
 166         return err;
 167 }
 168
 169 void thermal_unregister_governor(struct thermal_governor *governor)
 170 {
 171         struct thermal_zone_device *pos;
 172
 173         if (!governor)
 174                 return;
 175
 176         mutex_lock(&thermal_governor_lock);
 177
 178         if (!__find_governor(governor->name))
 179                 goto exit;
 180
 181         mutex_lock(&thermal_list_lock);
 182
 183         list_for_each_entry(pos, &thermal_tz_list, node) {
 184                 if (!strncasecmp(pos->governor->name, governor->name,
 185                                  THERMAL_NAME_LENGTH))
 186                         thermal_set_governor(pos, NULL);
 187         }
 188
 189         mutex_unlock(&thermal_list_lock);
 190         list_del(&governor->governor_list);
 191 exit:
 192         mutex_unlock(&thermal_governor_lock);
 193 }
 194
 195 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 196                                    char *policy)
 197 {
 198         struct thermal_governor *gov;
 199         int ret = -EINVAL;
 200
 201         mutex_lock(&thermal_governor_lock);
 202         mutex_lock(&tz->lock);
 203
 204         if (!device_is_registered(&tz->device))
 205                 goto exit;
 206
 207         gov = __find_governor(strim(policy));
 208         if (!gov)
 209                 goto exit;
 210
 211         ret = thermal_set_governor(tz, gov);
 212
 213 exit:
 214         mutex_unlock(&tz->lock);
 215         mutex_unlock(&thermal_governor_lock);
 216
 217         thermal_notify_tz_gov_change(tz->id, policy);
 218
 219         return ret;
 220 }
 221
 222 int thermal_build_list_of_policies(char *buf)
 223 {
 224         struct thermal_governor *pos;
 225         ssize_t count = 0;
 226
 227         mutex_lock(&thermal_governor_lock);
 228
 229         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 230                 count += sysfs_emit_at(buf, count, "%s ", pos->name);
 231         }
 232         count += sysfs_emit_at(buf, count, "\n");
 233
 234         mutex_unlock(&thermal_governor_lock);
 235
 236         return count;
 237 }
 238
 239 static void __init thermal_unregister_governors(void)
 240 {
 241         struct thermal_governor **governor;
 242
 243         for_each_governor_table(governor)
 244                 thermal_unregister_governor(*governor);
 245 }
 246
 247 static int __init thermal_register_governors(void)
 248 {
 249         int ret = 0;
 250         struct thermal_governor **governor;
 251
 252         for_each_governor_table(governor) {
 253                 ret = thermal_register_governor(*governor);
 254                 if (ret) {
 255                         pr_err("Failed to register governor: '%s'",
 256                                (*governor)->name);
 257                         break;
 258                 }
 259
 260                 pr_info("Registered thermal governor '%s'",
 261                         (*governor)->name);
 262         }
 263
 264         if (ret) {
 265                 struct thermal_governor **gov;
 266
 267                 for_each_governor_table(gov) {
 268                         if (gov == governor)
 269                                 break;
 270                         thermal_unregister_governor(*gov);
 271                 }
 272         }
 273
 274         return ret;
 275 }
 276
 277 /*
 278  * Zone update section: main control loop applied to each zone while monitoring
 279  *
 280  * in polling mode. The monitoring is done using a workqueue.
 281  * Same update may be done on a zone by calling thermal_zone_device_update().
 282  *
 283  * An update means:
 284  * - Non-critical trips will invoke the governor responsible for that zone;
 285  * - Hot trips will produce a notification to userspace;
 286  * - Critical trip point will cause a system shutdown.
 287  */
 288 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 289                                             unsigned long delay)
 290 {
 291         if (delay)
 292                 mod_delayed_work(system_freezable_power_efficient_wq,
 293                                  &tz->poll_queue, delay);
 294         else
 295                 cancel_delayed_work(&tz->poll_queue);
 296 }
 297
 298 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 299 {
 300         if (tz->mode != THERMAL_DEVICE_ENABLED)
 301                 thermal_zone_device_set_polling(tz, 0);
 302         else if (tz->passive)
 303                 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
 304         else if (tz->polling_delay_jiffies)
 305                 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
 306 }
 307
 308 static void handle_non_critical_trips(struct thermal_zone_device *tz,
 309                                       const struct thermal_trip *trip)
 310 {
 311         tz->governor ? tz->governor->throttle(tz, trip) :
 312                        def_governor->throttle(tz, trip);
 313 }
 314
 315 void thermal_zone_device_critical(struct thermal_zone_device *tz)
 316 {
 317         /*
 318          * poweroff_delay_ms must be a carefully profiled positive value.
 319          * Its a must for forced_emergency_poweroff_work to be scheduled.
 320          */
 321         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 322
 323         dev_emerg(&tz->device, "%s: critical temperature reached, "
 324                   "shutting down\n", tz->type);
 325
 326         hw_protection_shutdown("Temperature too high", poweroff_delay_ms);
 327 }
 328 EXPORT_SYMBOL(thermal_zone_device_critical);
 329
 330 static void handle_critical_trips(struct thermal_zone_device *tz,
 331                                   const struct thermal_trip *trip)
 332 {
 333         /* If we have not crossed the trip_temp, we do not care. */
 334         if (trip->temperature <= 0 || tz->temperature < trip->temperature)
 335                 return;
 336
 337         trace_thermal_zone_trip(tz, thermal_zone_trip_id(tz, trip), trip->type);
 338
 339         if (trip->type == THERMAL_TRIP_CRITICAL)
 340                 tz->ops->critical(tz);
 341         else if (tz->ops->hot)
 342                 tz->ops->hot(tz);
 343 }
 344
 345 static void handle_thermal_trip(struct thermal_zone_device *tz,
 346                                 const struct thermal_trip *trip)
 347 {
 348         if (trip->temperature == THERMAL_TEMP_INVALID)
 349                 return;
 350
 351         if (tz->last_temperature != THERMAL_TEMP_INVALID) {
 352                 if (tz->last_temperature < trip->temperature &&
 353                     tz->temperature >= trip->temperature)
 354                         thermal_notify_tz_trip_up(tz->id,
 355                                                   thermal_zone_trip_id(tz, trip),
 356                                                   tz->temperature);
 357                 if (tz->last_temperature >= trip->temperature &&
 358                     tz->temperature < trip->temperature - trip->hysteresis)
 359                         thermal_notify_tz_trip_down(tz->id,
 360                                                     thermal_zone_trip_id(tz, trip),
 361                                                     tz->temperature);
 362         }
 363
 364         if (trip->type == THERMAL_TRIP_CRITICAL || trip->type == THERMAL_TRIP_HOT)
 365                 handle_critical_trips(tz, trip);
 366         else
 367                 handle_non_critical_trips(tz, trip);
 368 }
 369
 370 static void update_temperature(struct thermal_zone_device *tz)
 371 {
 372         int temp, ret;
 373
 374         ret = __thermal_zone_get_temp(tz, &temp);
 375         if (ret) {
 376                 if (ret != -EAGAIN)
 377                         dev_warn(&tz->device,
 378                                  "failed to read out thermal zone (%d)\n",
 379                                  ret);
 380                 return;
 381         }
 382
 383         tz->last_temperature = tz->temperature;
 384         tz->temperature = temp;
 385
 386         trace_thermal_temperature(tz);
 387
 388         thermal_genl_sampling_temp(tz->id, temp);
 389 }
 390
 391 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 392 {
 393         struct thermal_instance *pos;
 394         tz->temperature = THERMAL_TEMP_INVALID;
 395         tz->prev_low_trip = -INT_MAX;
 396         tz->prev_high_trip = INT_MAX;
 397         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 398                 pos->initialized = false;
 399 }
 400
 401 void __thermal_zone_device_update(struct thermal_zone_device *tz,
 402                                   enum thermal_notify_event event)
 403 {
 404         const struct thermal_trip *trip;
 405
 406         if (tz->suspended)
 407                 return;
 408
 409         if (WARN_ONCE(!tz->ops->get_temp,
 410                       "'%s' must not be called without 'get_temp' ops set\n",
 411                       __func__))
 412                 return;
 413
 414         if (!thermal_zone_device_is_enabled(tz))
 415                 return;
 416
 417         update_temperature(tz);
 418
 419         __thermal_zone_set_trips(tz);
 420
 421         tz->notify_event = event;
 422
 423         for_each_trip(tz, trip)
 424                 handle_thermal_trip(tz, trip);
 425
 426         monitor_thermal_zone(tz);
 427 }
 428
 429 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
 430                                         enum thermal_device_mode mode)
 431 {
 432         int ret = 0;
 433
 434         mutex_lock(&tz->lock);
 435
 436         /* do nothing if mode isn't changing */
 437         if (mode == tz->mode) {
 438                 mutex_unlock(&tz->lock);
 439
 440                 return ret;
 441         }
 442
 443         if (!device_is_registered(&tz->device)) {
 444                 mutex_unlock(&tz->lock);
 445
 446                 return -ENODEV;
 447         }
 448
 449         if (tz->ops->change_mode)
 450                 ret = tz->ops->change_mode(tz, mode);
 451
 452         if (!ret)
 453                 tz->mode = mode;
 454
 455         __thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 456
 457         mutex_unlock(&tz->lock);
 458
 459         if (mode == THERMAL_DEVICE_ENABLED)
 460                 thermal_notify_tz_enable(tz->id);
 461         else
 462                 thermal_notify_tz_disable(tz->id);
 463
 464         return ret;
 465 }
 466
 467 int thermal_zone_device_enable(struct thermal_zone_device *tz)
 468 {
 469         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
 470 }
 471 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
 472
 473 int thermal_zone_device_disable(struct thermal_zone_device *tz)
 474 {
 475         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
 476 }
 477 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
 478
 479 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
 480 {
 481         lockdep_assert_held(&tz->lock);
 482
 483         return tz->mode == THERMAL_DEVICE_ENABLED;
 484 }
 485
 486 void thermal_zone_device_update(struct thermal_zone_device *tz,
 487                                 enum thermal_notify_event event)
 488 {
 489         mutex_lock(&tz->lock);
 490         if (device_is_registered(&tz->device))
 491                 __thermal_zone_device_update(tz, event);
 492         mutex_unlock(&tz->lock);
 493 }
 494 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 495
 496 static void thermal_zone_device_check(struct work_struct *work)
 497 {
 498         struct thermal_zone_device *tz = container_of(work, struct
 499                                                       thermal_zone_device,
 500                                                       poll_queue.work);
 501         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 502 }
 503
 504 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
 505                               void *data)
 506 {
 507         struct thermal_governor *gov;
 508         int ret = 0;
 509
 510         mutex_lock(&thermal_governor_lock);
 511         list_for_each_entry(gov, &thermal_governor_list, governor_list) {
 512                 ret = cb(gov, data);
 513                 if (ret)
 514                         break;
 515         }
 516         mutex_unlock(&thermal_governor_lock);
 517
 518         return ret;
 519 }
 520
 521 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
 522                                               void *), void *data)
 523 {
 524         struct thermal_cooling_device *cdev;
 525         int ret = 0;
 526
 527         mutex_lock(&thermal_list_lock);
 528         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 529                 ret = cb(cdev, data);
 530                 if (ret)
 531                         break;
 532         }
 533         mutex_unlock(&thermal_list_lock);
 534
 535         return ret;
 536 }
 537
 538 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
 539                           void *data)
 540 {
 541         struct thermal_zone_device *tz;
 542         int ret = 0;
 543
 544         mutex_lock(&thermal_list_lock);
 545         list_for_each_entry(tz, &thermal_tz_list, node) {
 546                 ret = cb(tz, data);
 547                 if (ret)
 548                         break;
 549         }
 550         mutex_unlock(&thermal_list_lock);
 551
 552         return ret;
 553 }
 554
 555 struct thermal_zone_device *thermal_zone_get_by_id(int id)
 556 {
 557         struct thermal_zone_device *tz, *match = NULL;
 558
 559         mutex_lock(&thermal_list_lock);
 560         list_for_each_entry(tz, &thermal_tz_list, node) {
 561                 if (tz->id == id) {
 562                         match = tz;
 563                         break;
 564                 }
 565         }
 566         mutex_unlock(&thermal_list_lock);
 567
 568         return match;
 569 }
 570
 571 /*
 572  * Device management section: cooling devices, zones devices, and binding
 573  *
 574  * Set of functions provided by the thermal core for:
 575  * - cooling devices lifecycle: registration, unregistration,
 576  *                              binding, and unbinding.
 577  * - thermal zone devices lifecycle: registration, unregistration,
 578  *                                   binding, and unbinding.
 579  */
 580
 581 /**
 582  * thermal_bind_cdev_to_trip - bind a cooling device to a thermal zone
 583  * @tz:         pointer to struct thermal_zone_device
 584  * @trip:       trip point the cooling devices is associated with in this zone.
 585  * @cdev:       pointer to struct thermal_cooling_device
 586  * @upper:      the Maximum cooling state for this trip point.
 587  *              THERMAL_NO_LIMIT means no upper limit,
 588  *              and the cooling device can be in max_state.
 589  * @lower:      the Minimum cooling state can be used for this trip point.
 590  *              THERMAL_NO_LIMIT means no lower limit,
 591  *              and the cooling device can be in cooling state 0.
 592  * @weight:     The weight of the cooling device to be bound to the
 593  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 594  *              default value
 595  *
 596  * This interface function bind a thermal cooling device to the certain trip
 597  * point of a thermal zone device.
 598  * This function is usually called in the thermal zone device .bind callback.
 599  *
 600  * Return: 0 on success, the proper error value otherwise.
 601  */
 602 int thermal_bind_cdev_to_trip(struct thermal_zone_device *tz,
 603                                      const struct thermal_trip *trip,
 604                                      struct thermal_cooling_device *cdev,
 605                                      unsigned long upper, unsigned long lower,
 606                                      unsigned int weight)
 607 {
 608         struct thermal_instance *dev;
 609         struct thermal_instance *pos;
 610         struct thermal_zone_device *pos1;
 611         struct thermal_cooling_device *pos2;
 612         bool upper_no_limit;
 613         int result;
 614
 615         list_for_each_entry(pos1, &thermal_tz_list, node) {
 616                 if (pos1 == tz)
 617                         break;
 618         }
 619         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 620                 if (pos2 == cdev)
 621                         break;
 622         }
 623
 624         if (tz != pos1 || cdev != pos2)
 625                 return -EINVAL;
 626
 627         /* lower default 0, upper default max_state */
 628         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 629
 630         if (upper == THERMAL_NO_LIMIT) {
 631                 upper = cdev->max_state;
 632                 upper_no_limit = true;
 633         } else {
 634                 upper_no_limit = false;
 635         }
 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->upper_no_limit = upper_no_limit;
 648         dev->lower = lower;
 649         dev->target = THERMAL_NO_TARGET;
 650         dev->weight = weight;
 651
 652         result = ida_alloc(&tz->ida, GFP_KERNEL);
 653         if (result < 0)
 654                 goto free_mem;
 655
 656         dev->id = result;
 657         sprintf(dev->name, "cdev%d", dev->id);
 658         result =
 659             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 660         if (result)
 661                 goto release_ida;
 662
 663         snprintf(dev->attr_name, sizeof(dev->attr_name), "cdev%d_trip_point",
 664                  dev->id);
 665         sysfs_attr_init(&dev->attr.attr);
 666         dev->attr.attr.name = dev->attr_name;
 667         dev->attr.attr.mode = 0444;
 668         dev->attr.show = trip_point_show;
 669         result = device_create_file(&tz->device, &dev->attr);
 670         if (result)
 671                 goto remove_symbol_link;
 672
 673         snprintf(dev->weight_attr_name, sizeof(dev->weight_attr_name),
 674                  "cdev%d_weight", dev->id);
 675         sysfs_attr_init(&dev->weight_attr.attr);
 676         dev->weight_attr.attr.name = dev->weight_attr_name;
 677         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 678         dev->weight_attr.show = weight_show;
 679         dev->weight_attr.store = weight_store;
 680         result = device_create_file(&tz->device, &dev->weight_attr);
 681         if (result)
 682                 goto remove_trip_file;
 683
 684         mutex_lock(&tz->lock);
 685         mutex_lock(&cdev->lock);
 686         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 687                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 688                         result = -EEXIST;
 689                         break;
 690                 }
 691         if (!result) {
 692                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 693                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 694                 atomic_set(&tz->need_update, 1);
 695         }
 696         mutex_unlock(&cdev->lock);
 697         mutex_unlock(&tz->lock);
 698
 699         if (!result)
 700                 return 0;
 701
 702         device_remove_file(&tz->device, &dev->weight_attr);
 703 remove_trip_file:
 704         device_remove_file(&tz->device, &dev->attr);
 705 remove_symbol_link:
 706         sysfs_remove_link(&tz->device.kobj, dev->name);
 707 release_ida:
 708         ida_free(&tz->ida, dev->id);
 709 free_mem:
 710         kfree(dev);
 711         return result;
 712 }
 713 EXPORT_SYMBOL_GPL(thermal_bind_cdev_to_trip);
 714
 715 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 716                                      int trip_index,
 717                                      struct thermal_cooling_device *cdev,
 718                                      unsigned long upper, unsigned long lower,
 719                                      unsigned int weight)
 720 {
 721         if (trip_index < 0 || trip_index >= tz->num_trips)
 722                 return -EINVAL;
 723
 724         return thermal_bind_cdev_to_trip(tz, &tz->trips[trip_index], cdev,
 725                                          upper, lower, weight);
 726 }
 727 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 728
 729 /**
 730  * thermal_unbind_cdev_from_trip - unbind a cooling device from a thermal zone.
 731  * @tz:         pointer to a struct thermal_zone_device.
 732  * @trip:       trip point the cooling devices is associated with in this zone.
 733  * @cdev:       pointer to a struct thermal_cooling_device.
 734  *
 735  * This interface function unbind a thermal cooling device from the certain
 736  * trip point of a thermal zone device.
 737  * This function is usually called in the thermal zone device .unbind callback.
 738  *
 739  * Return: 0 on success, the proper error value otherwise.
 740  */
 741 int thermal_unbind_cdev_from_trip(struct thermal_zone_device *tz,
 742                                   const struct thermal_trip *trip,
 743                                   struct thermal_cooling_device *cdev)
 744 {
 745         struct thermal_instance *pos, *next;
 746
 747         mutex_lock(&tz->lock);
 748         mutex_lock(&cdev->lock);
 749         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 750                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 751                         list_del(&pos->tz_node);
 752                         list_del(&pos->cdev_node);
 753                         mutex_unlock(&cdev->lock);
 754                         mutex_unlock(&tz->lock);
 755                         goto unbind;
 756                 }
 757         }
 758         mutex_unlock(&cdev->lock);
 759         mutex_unlock(&tz->lock);
 760
 761         return -ENODEV;
 762
 763 unbind:
 764         device_remove_file(&tz->device, &pos->weight_attr);
 765         device_remove_file(&tz->device, &pos->attr);
 766         sysfs_remove_link(&tz->device.kobj, pos->name);
 767         ida_free(&tz->ida, pos->id);
 768         kfree(pos);
 769         return 0;
 770 }
 771 EXPORT_SYMBOL_GPL(thermal_unbind_cdev_from_trip);
 772
 773 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 774                                        int trip_index,
 775                                        struct thermal_cooling_device *cdev)
 776 {
 777         if (trip_index < 0 || trip_index >= tz->num_trips)
 778                 return -EINVAL;
 779
 780         return thermal_unbind_cdev_from_trip(tz, &tz->trips[trip_index], cdev);
 781 }
 782 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 783
 784 static void thermal_release(struct device *dev)
 785 {
 786         struct thermal_zone_device *tz;
 787         struct thermal_cooling_device *cdev;
 788
 789         if (!strncmp(dev_name(dev), "thermal_zone",
 790                      sizeof("thermal_zone") - 1)) {
 791                 tz = to_thermal_zone(dev);
 792                 thermal_zone_destroy_device_groups(tz);
 793                 mutex_destroy(&tz->lock);
 794                 kfree(tz);
 795         } else if (!strncmp(dev_name(dev), "cooling_device",
 796                             sizeof("cooling_device") - 1)) {
 797                 cdev = to_cooling_device(dev);
 798                 thermal_cooling_device_destroy_sysfs(cdev);
 799                 kfree(cdev->type);
 800                 ida_free(&thermal_cdev_ida, cdev->id);
 801                 kfree(cdev);
 802         }
 803 }
 804
 805 static struct class *thermal_class;
 806
 807 static inline
 808 void print_bind_err_msg(struct thermal_zone_device *tz,
 809                         struct thermal_cooling_device *cdev, int ret)
 810 {
 811         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 812                 tz->type, cdev->type, ret);
 813 }
 814
 815 static void bind_cdev(struct thermal_cooling_device *cdev)
 816 {
 817         int ret;
 818         struct thermal_zone_device *pos = NULL;
 819
 820         list_for_each_entry(pos, &thermal_tz_list, node) {
 821                 if (pos->ops->bind) {
 822                         ret = pos->ops->bind(pos, cdev);
 823                         if (ret)
 824                                 print_bind_err_msg(pos, cdev, ret);
 825                 }
 826         }
 827 }
 828
 829 /**
 830  * __thermal_cooling_device_register() - register a new thermal cooling device
 831  * @np:         a pointer to a device tree node.
 832  * @type:       the thermal cooling device type.
 833  * @devdata:    device private data.
 834  * @ops:                standard thermal cooling devices callbacks.
 835  *
 836  * This interface function adds a new thermal cooling device (fan/processor/...)
 837  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 838  * to all the thermal zone devices registered at the same time.
 839  * It also gives the opportunity to link the cooling device to a device tree
 840  * node, so that it can be bound to a thermal zone created out of device tree.
 841  *
 842  * Return: a pointer to the created struct thermal_cooling_device or an
 843  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 844  */
 845 static struct thermal_cooling_device *
 846 __thermal_cooling_device_register(struct device_node *np,
 847                                   const char *type, void *devdata,
 848                                   const struct thermal_cooling_device_ops *ops)
 849 {
 850         struct thermal_cooling_device *cdev;
 851         struct thermal_zone_device *pos = NULL;
 852         int id, ret;
 853
 854         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 855             !ops->set_cur_state)
 856                 return ERR_PTR(-EINVAL);
 857
 858         if (!thermal_class)
 859                 return ERR_PTR(-ENODEV);
 860
 861         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 862         if (!cdev)
 863                 return ERR_PTR(-ENOMEM);
 864
 865         ret = ida_alloc(&thermal_cdev_ida, GFP_KERNEL);
 866         if (ret < 0)
 867                 goto out_kfree_cdev;
 868         cdev->id = ret;
 869         id = ret;
 870
 871         cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
 872         if (!cdev->type) {
 873                 ret = -ENOMEM;
 874                 goto out_ida_remove;
 875         }
 876
 877         mutex_init(&cdev->lock);
 878         INIT_LIST_HEAD(&cdev->thermal_instances);
 879         cdev->np = np;
 880         cdev->ops = ops;
 881         cdev->updated = false;
 882         cdev->device.class = thermal_class;
 883         cdev->devdata = devdata;
 884
 885         ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
 886         if (ret)
 887                 goto out_cdev_type;
 888
 889         thermal_cooling_device_setup_sysfs(cdev);
 890
 891         ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 892         if (ret)
 893                 goto out_cooling_dev;
 894
 895         ret = device_register(&cdev->device);
 896         if (ret) {
 897                 /* thermal_release() handles rest of the cleanup */
 898                 put_device(&cdev->device);
 899                 return ERR_PTR(ret);
 900         }
 901
 902         /* Add 'this' new cdev to the global cdev list */
 903         mutex_lock(&thermal_list_lock);
 904
 905         list_add(&cdev->node, &thermal_cdev_list);
 906
 907         /* Update binding information for 'this' new cdev */
 908         bind_cdev(cdev);
 909
 910         list_for_each_entry(pos, &thermal_tz_list, node)
 911                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
 912                         thermal_zone_device_update(pos,
 913                                                    THERMAL_EVENT_UNSPECIFIED);
 914
 915         mutex_unlock(&thermal_list_lock);
 916
 917         return cdev;
 918
 919 out_cooling_dev:
 920         thermal_cooling_device_destroy_sysfs(cdev);
 921 out_cdev_type:
 922         kfree(cdev->type);
 923 out_ida_remove:
 924         ida_free(&thermal_cdev_ida, id);
 925 out_kfree_cdev:
 926         kfree(cdev);
 927         return ERR_PTR(ret);
 928 }
 929
 930 /**
 931  * thermal_cooling_device_register() - register a new thermal cooling device
 932  * @type:       the thermal cooling device type.
 933  * @devdata:    device private data.
 934  * @ops:                standard thermal cooling devices callbacks.
 935  *
 936  * This interface function adds a new thermal cooling device (fan/processor/...)
 937  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 938  * to all the thermal zone devices registered at the same time.
 939  *
 940  * Return: a pointer to the created struct thermal_cooling_device or an
 941  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 942  */
 943 struct thermal_cooling_device *
 944 thermal_cooling_device_register(const char *type, void *devdata,
 945                                 const struct thermal_cooling_device_ops *ops)
 946 {
 947         return __thermal_cooling_device_register(NULL, type, devdata, ops);
 948 }
 949 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
 950
 951 /**
 952  * thermal_of_cooling_device_register() - register an OF thermal cooling device
 953  * @np:         a pointer to a device tree node.
 954  * @type:       the thermal cooling device type.
 955  * @devdata:    device private data.
 956  * @ops:                standard thermal cooling devices callbacks.
 957  *
 958  * This function will register a cooling device with device tree node reference.
 959  * This interface function adds a new thermal cooling device (fan/processor/...)
 960  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 961  * to all the thermal zone devices registered at the same time.
 962  *
 963  * Return: a pointer to the created struct thermal_cooling_device or an
 964  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 965  */
 966 struct thermal_cooling_device *
 967 thermal_of_cooling_device_register(struct device_node *np,
 968                                    const char *type, void *devdata,
 969                                    const struct thermal_cooling_device_ops *ops)
 970 {
 971         return __thermal_cooling_device_register(np, type, devdata, ops);
 972 }
 973 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
 974
 975 static void thermal_cooling_device_release(struct device *dev, void *res)
 976 {
 977         thermal_cooling_device_unregister(
 978                                 *(struct thermal_cooling_device **)res);
 979 }
 980
 981 /**
 982  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
 983  *                                             device
 984  * @dev:        a valid struct device pointer of a sensor device.
 985  * @np:         a pointer to a device tree node.
 986  * @type:       the thermal cooling device type.
 987  * @devdata:    device private data.
 988  * @ops:        standard thermal cooling devices callbacks.
 989  *
 990  * This function will register a cooling device with device tree node reference.
 991  * This interface function adds a new thermal cooling device (fan/processor/...)
 992  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 993  * to all the thermal zone devices registered at the same time.
 994  *
 995  * Return: a pointer to the created struct thermal_cooling_device or an
 996  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 997  */
 998 struct thermal_cooling_device *
 999 devm_thermal_of_cooling_device_register(struct device *dev,
1000                                 struct device_node *np,
1001                                 char *type, void *devdata,
1002                                 const struct thermal_cooling_device_ops *ops)
1003 {
1004         struct thermal_cooling_device **ptr, *tcd;
1005
1006         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1007                            GFP_KERNEL);
1008         if (!ptr)
1009                 return ERR_PTR(-ENOMEM);
1010
1011         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1012         if (IS_ERR(tcd)) {
1013                 devres_free(ptr);
1014                 return tcd;
1015         }
1016
1017         *ptr = tcd;
1018         devres_add(dev, ptr);
1019
1020         return tcd;
1021 }
1022 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1023
1024 static bool thermal_cooling_device_present(struct thermal_cooling_device *cdev)
1025 {
1026         struct thermal_cooling_device *pos = NULL;
1027
1028         list_for_each_entry(pos, &thermal_cdev_list, node) {
1029                 if (pos == cdev)
1030                         return true;
1031         }
1032
1033         return false;
1034 }
1035
1036 /**
1037  * thermal_cooling_device_update - Update a cooling device object
1038  * @cdev: Target cooling device.
1039  *
1040  * Update @cdev to reflect a change of the underlying hardware or platform.
1041  *
1042  * Must be called when the maximum cooling state of @cdev becomes invalid and so
1043  * its .get_max_state() callback needs to be run to produce the new maximum
1044  * cooling state value.
1045  */
1046 void thermal_cooling_device_update(struct thermal_cooling_device *cdev)
1047 {
1048         struct thermal_instance *ti;
1049         unsigned long state;
1050
1051         if (IS_ERR_OR_NULL(cdev))
1052                 return;
1053
1054         /*
1055          * Hold thermal_list_lock throughout the update to prevent the device
1056          * from going away while being updated.
1057          */
1058         mutex_lock(&thermal_list_lock);
1059
1060         if (!thermal_cooling_device_present(cdev))
1061                 goto unlock_list;
1062
1063         /*
1064          * Update under the cdev lock to prevent the state from being set beyond
1065          * the new limit concurrently.
1066          */
1067         mutex_lock(&cdev->lock);
1068
1069         if (cdev->ops->get_max_state(cdev, &cdev->max_state))
1070                 goto unlock;
1071
1072         thermal_cooling_device_stats_reinit(cdev);
1073
1074         list_for_each_entry(ti, &cdev->thermal_instances, cdev_node) {
1075                 if (ti->upper == cdev->max_state)
1076                         continue;
1077
1078                 if (ti->upper < cdev->max_state) {
1079                         if (ti->upper_no_limit)
1080                                 ti->upper = cdev->max_state;
1081
1082                         continue;
1083                 }
1084
1085                 ti->upper = cdev->max_state;
1086                 if (ti->lower > ti->upper)
1087                         ti->lower = ti->upper;
1088
1089                 if (ti->target == THERMAL_NO_TARGET)
1090                         continue;
1091
1092                 if (ti->target > ti->upper)
1093                         ti->target = ti->upper;
1094         }
1095
1096         if (cdev->ops->get_cur_state(cdev, &state) || state > cdev->max_state)
1097                 goto unlock;
1098
1099         thermal_cooling_device_stats_update(cdev, state);
1100
1101 unlock:
1102         mutex_unlock(&cdev->lock);
1103
1104 unlock_list:
1105         mutex_unlock(&thermal_list_lock);
1106 }
1107 EXPORT_SYMBOL_GPL(thermal_cooling_device_update);
1108
1109 /**
1110  * thermal_cooling_device_unregister - removes a thermal cooling device
1111  * @cdev:       the thermal cooling device to remove.
1112  *
1113  * thermal_cooling_device_unregister() must be called when a registered
1114  * thermal cooling device is no longer needed.
1115  */
1116 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1117 {
1118         struct thermal_zone_device *tz;
1119
1120         if (!cdev)
1121                 return;
1122
1123         mutex_lock(&thermal_list_lock);
1124
1125         if (!thermal_cooling_device_present(cdev)) {
1126                 mutex_unlock(&thermal_list_lock);
1127                 return;
1128         }
1129
1130         list_del(&cdev->node);
1131
1132         /* Unbind all thermal zones associated with 'this' cdev */
1133         list_for_each_entry(tz, &thermal_tz_list, node) {
1134                 if (tz->ops->unbind)
1135                         tz->ops->unbind(tz, cdev);
1136         }
1137
1138         mutex_unlock(&thermal_list_lock);
1139
1140         device_unregister(&cdev->device);
1141 }
1142 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1143
1144 static void bind_tz(struct thermal_zone_device *tz)
1145 {
1146         int ret;
1147         struct thermal_cooling_device *pos = NULL;
1148
1149         if (!tz->ops->bind)
1150                 return;
1151
1152         mutex_lock(&thermal_list_lock);
1153
1154         list_for_each_entry(pos, &thermal_cdev_list, node) {
1155                 ret = tz->ops->bind(tz, pos);
1156                 if (ret)
1157                         print_bind_err_msg(tz, pos, ret);
1158         }
1159
1160         mutex_unlock(&thermal_list_lock);
1161 }
1162
1163 static void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms)
1164 {
1165         *delay_jiffies = msecs_to_jiffies(delay_ms);
1166         if (delay_ms > 1000)
1167                 *delay_jiffies = round_jiffies(*delay_jiffies);
1168 }
1169
1170 int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp)
1171 {
1172         int i, ret = -EINVAL;
1173
1174         if (tz->ops->get_crit_temp)
1175                 return tz->ops->get_crit_temp(tz, temp);
1176
1177         if (!tz->trips)
1178                 return -EINVAL;
1179
1180         mutex_lock(&tz->lock);
1181
1182         for (i = 0; i < tz->num_trips; i++) {
1183                 if (tz->trips[i].type == THERMAL_TRIP_CRITICAL) {
1184                         *temp = tz->trips[i].temperature;
1185                         ret = 0;
1186                         break;
1187                 }
1188         }
1189
1190         mutex_unlock(&tz->lock);
1191
1192         return ret;
1193 }
1194 EXPORT_SYMBOL_GPL(thermal_zone_get_crit_temp);
1195
1196 /**
1197  * thermal_zone_device_register_with_trips() - register a new thermal zone device
1198  * @type:       the thermal zone device type
1199  * @trips:      a pointer to an array of thermal trips
1200  * @num_trips:  the number of trip points the thermal zone support
1201  * @mask:       a bit string indicating the writeablility of trip points
1202  * @devdata:    private device data
1203  * @ops:        standard thermal zone device callbacks
1204  * @tzp:        thermal zone platform parameters
1205  * @passive_delay: number of milliseconds to wait between polls when
1206  *                 performing passive cooling
1207  * @polling_delay: number of milliseconds to wait between polls when checking
1208  *                 whether trip points have been crossed (0 for interrupt
1209  *                 driven systems)
1210  *
1211  * This interface function adds a new thermal zone device (sensor) to
1212  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1213  * thermal cooling devices registered at the same time.
1214  * thermal_zone_device_unregister() must be called when the device is no
1215  * longer needed. The passive cooling depends on the .get_trend() return value.
1216  *
1217  * Return: a pointer to the created struct thermal_zone_device or an
1218  * in case of error, an ERR_PTR. Caller must check return value with
1219  * IS_ERR*() helpers.
1220  */
1221 struct thermal_zone_device *
1222 thermal_zone_device_register_with_trips(const char *type, struct thermal_trip *trips, int num_trips, int mask,
1223                                         void *devdata, struct thermal_zone_device_ops *ops,
1224                                         const struct thermal_zone_params *tzp, int passive_delay,
1225                                         int polling_delay)
1226 {
1227         struct thermal_zone_device *tz;
1228         int id;
1229         int result;
1230         struct thermal_governor *governor;
1231
1232         if (!type || strlen(type) == 0) {
1233                 pr_err("No thermal zone type defined\n");
1234                 return ERR_PTR(-EINVAL);
1235         }
1236
1237         if (strlen(type) >= THERMAL_NAME_LENGTH) {
1238                 pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1239                        type, THERMAL_NAME_LENGTH);
1240                 return ERR_PTR(-EINVAL);
1241         }
1242
1243         /*
1244          * Max trip count can't exceed 31 as the "mask >> num_trips" condition.
1245          * For example, shifting by 32 will result in compiler warning:
1246          * warning: right shift count >= width of type [-Wshift-count- overflow]
1247          *
1248          * Also "mask >> num_trips" will always be true with 32 bit shift.
1249          * E.g. mask = 0x80000000 for trip id 31 to be RW. Then
1250          * mask >> 32 = 0x80000000
1251          * This will result in failure for the below condition.
1252          *
1253          * Check will be true when the bit 31 of the mask is set.
1254          * 32 bit shift will cause overflow of 4 byte integer.
1255          */
1256         if (num_trips > (BITS_PER_TYPE(int) - 1) || num_trips < 0 || mask >> num_trips) {
1257                 pr_err("Incorrect number of thermal trips\n");
1258                 return ERR_PTR(-EINVAL);
1259         }
1260
1261         if (!ops) {
1262                 pr_err("Thermal zone device ops not defined\n");
1263                 return ERR_PTR(-EINVAL);
1264         }
1265
1266         if (num_trips > 0 && !trips)
1267                 return ERR_PTR(-EINVAL);
1268
1269         if (!thermal_class)
1270                 return ERR_PTR(-ENODEV);
1271
1272         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1273         if (!tz)
1274                 return ERR_PTR(-ENOMEM);
1275
1276         if (tzp) {
1277                 tz->tzp = kmemdup(tzp, sizeof(*tzp), GFP_KERNEL);
1278                 if (!tz->tzp) {
1279                         result = -ENOMEM;
1280                         goto free_tz;
1281                 }
1282         }
1283
1284         INIT_LIST_HEAD(&tz->thermal_instances);
1285         ida_init(&tz->ida);
1286         mutex_init(&tz->lock);
1287         id = ida_alloc(&thermal_tz_ida, GFP_KERNEL);
1288         if (id < 0) {
1289                 result = id;
1290                 goto free_tzp;
1291         }
1292
1293         tz->id = id;
1294         strscpy(tz->type, type, sizeof(tz->type));
1295
1296         if (!ops->critical)
1297                 ops->critical = thermal_zone_device_critical;
1298
1299         tz->ops = ops;
1300         tz->device.class = thermal_class;
1301         tz->devdata = devdata;
1302         tz->trips = trips;
1303         tz->num_trips = num_trips;
1304
1305         thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1306         thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1307
1308         /* sys I/F */
1309         /* Add nodes that are always present via .groups */
1310         result = thermal_zone_create_device_groups(tz, mask);
1311         if (result)
1312                 goto remove_id;
1313
1314         /* A new thermal zone needs to be updated anyway. */
1315         atomic_set(&tz->need_update, 1);
1316
1317         result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1318         if (result) {
1319                 thermal_zone_destroy_device_groups(tz);
1320                 goto remove_id;
1321         }
1322         result = device_register(&tz->device);
1323         if (result)
1324                 goto release_device;
1325
1326         /* Update 'this' zone's governor information */
1327         mutex_lock(&thermal_governor_lock);
1328
1329         if (tz->tzp)
1330                 governor = __find_governor(tz->tzp->governor_name);
1331         else
1332                 governor = def_governor;
1333
1334         result = thermal_set_governor(tz, governor);
1335         if (result) {
1336                 mutex_unlock(&thermal_governor_lock);
1337                 goto unregister;
1338         }
1339
1340         mutex_unlock(&thermal_governor_lock);
1341
1342         if (!tz->tzp || !tz->tzp->no_hwmon) {
1343                 result = thermal_add_hwmon_sysfs(tz);
1344                 if (result)
1345                         goto unregister;
1346         }
1347
1348         mutex_lock(&thermal_list_lock);
1349         list_add_tail(&tz->node, &thermal_tz_list);
1350         mutex_unlock(&thermal_list_lock);
1351
1352         /* Bind cooling devices for this zone */
1353         bind_tz(tz);
1354
1355         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1356
1357         thermal_zone_device_init(tz);
1358         /* Update the new thermal zone and mark it as already updated. */
1359         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1360                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1361
1362         thermal_notify_tz_create(tz->id, tz->type);
1363
1364         return tz;
1365
1366 unregister:
1367         device_del(&tz->device);
1368 release_device:
1369         put_device(&tz->device);
1370 remove_id:
1371         ida_free(&thermal_tz_ida, id);
1372 free_tzp:
1373         kfree(tz->tzp);
1374 free_tz:
1375         kfree(tz);
1376         return ERR_PTR(result);
1377 }
1378 EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1379
1380 struct thermal_zone_device *thermal_tripless_zone_device_register(
1381                                         const char *type,
1382                                         void *devdata,
1383                                         struct thermal_zone_device_ops *ops,
1384                                         const struct thermal_zone_params *tzp)
1385 {
1386         return thermal_zone_device_register_with_trips(type, NULL, 0, 0, devdata,
1387                                                        ops, tzp, 0, 0);
1388 }
1389 EXPORT_SYMBOL_GPL(thermal_tripless_zone_device_register);
1390
1391 void *thermal_zone_device_priv(struct thermal_zone_device *tzd)
1392 {
1393         return tzd->devdata;
1394 }
1395 EXPORT_SYMBOL_GPL(thermal_zone_device_priv);
1396
1397 const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
1398 {
1399         return tzd->type;
1400 }
1401 EXPORT_SYMBOL_GPL(thermal_zone_device_type);
1402
1403 int thermal_zone_device_id(struct thermal_zone_device *tzd)
1404 {
1405         return tzd->id;
1406 }
1407 EXPORT_SYMBOL_GPL(thermal_zone_device_id);
1408
1409 struct device *thermal_zone_device(struct thermal_zone_device *tzd)
1410 {
1411         return &tzd->device;
1412 }
1413 EXPORT_SYMBOL_GPL(thermal_zone_device);
1414
1415 /**
1416  * thermal_zone_device_unregister - removes the registered thermal zone device
1417  * @tz: the thermal zone device to remove
1418  */
1419 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1420 {
1421         int tz_id;
1422         struct thermal_cooling_device *cdev;
1423         struct thermal_zone_device *pos = NULL;
1424
1425         if (!tz)
1426                 return;
1427
1428         tz_id = tz->id;
1429
1430         mutex_lock(&thermal_list_lock);
1431         list_for_each_entry(pos, &thermal_tz_list, node)
1432                 if (pos == tz)
1433                         break;
1434         if (pos != tz) {
1435                 /* thermal zone device not found */
1436                 mutex_unlock(&thermal_list_lock);
1437                 return;
1438         }
1439         list_del(&tz->node);
1440
1441         /* Unbind all cdevs associated with 'this' thermal zone */
1442         list_for_each_entry(cdev, &thermal_cdev_list, node)
1443                 if (tz->ops->unbind)
1444                         tz->ops->unbind(tz, cdev);
1445
1446         mutex_unlock(&thermal_list_lock);
1447
1448         cancel_delayed_work_sync(&tz->poll_queue);
1449
1450         thermal_set_governor(tz, NULL);
1451
1452         thermal_remove_hwmon_sysfs(tz);
1453         ida_free(&thermal_tz_ida, tz->id);
1454         ida_destroy(&tz->ida);
1455
1456         mutex_lock(&tz->lock);
1457         device_del(&tz->device);
1458         mutex_unlock(&tz->lock);
1459
1460         kfree(tz->tzp);
1461
1462         put_device(&tz->device);
1463
1464         thermal_notify_tz_delete(tz_id);
1465 }
1466 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1467
1468 /**
1469  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1470  * @name: thermal zone name to fetch the temperature
1471  *
1472  * When only one zone is found with the passed name, returns a reference to it.
1473  *
1474  * Return: On success returns a reference to an unique thermal zone with
1475  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1476  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1477  */
1478 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1479 {
1480         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1481         unsigned int found = 0;
1482
1483         if (!name)
1484                 goto exit;
1485
1486         mutex_lock(&thermal_list_lock);
1487         list_for_each_entry(pos, &thermal_tz_list, node)
1488                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1489                         found++;
1490                         ref = pos;
1491                 }
1492         mutex_unlock(&thermal_list_lock);
1493
1494         /* nothing has been found, thus an error code for it */
1495         if (found == 0)
1496                 ref = ERR_PTR(-ENODEV);
1497         else if (found > 1)
1498         /* Success only when an unique zone is found */
1499                 ref = ERR_PTR(-EEXIST);
1500
1501 exit:
1502         return ref;
1503 }
1504 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1505
1506 static int thermal_pm_notify(struct notifier_block *nb,
1507                              unsigned long mode, void *_unused)
1508 {
1509         struct thermal_zone_device *tz;
1510
1511         switch (mode) {
1512         case PM_HIBERNATION_PREPARE:
1513         case PM_RESTORE_PREPARE:
1514         case PM_SUSPEND_PREPARE:
1515                 mutex_lock(&thermal_list_lock);
1516
1517                 list_for_each_entry(tz, &thermal_tz_list, node) {
1518                         mutex_lock(&tz->lock);
1519
1520                         tz->suspended = true;
1521
1522                         mutex_unlock(&tz->lock);
1523                 }
1524
1525                 mutex_unlock(&thermal_list_lock);
1526                 break;
1527         case PM_POST_HIBERNATION:
1528         case PM_POST_RESTORE:
1529         case PM_POST_SUSPEND:
1530                 mutex_lock(&thermal_list_lock);
1531
1532                 list_for_each_entry(tz, &thermal_tz_list, node) {
1533                         mutex_lock(&tz->lock);
1534
1535                         tz->suspended = false;
1536
1537                         thermal_zone_device_init(tz);
1538                         __thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1539
1540                         mutex_unlock(&tz->lock);
1541                 }
1542
1543                 mutex_unlock(&thermal_list_lock);
1544                 break;
1545         default:
1546                 break;
1547         }
1548         return 0;
1549 }
1550
1551 static struct notifier_block thermal_pm_nb = {
1552         .notifier_call = thermal_pm_notify,
1553 };
1554
1555 static int __init thermal_init(void)
1556 {
1557         int result;
1558
1559         result = thermal_netlink_init();
1560         if (result)
1561                 goto error;
1562
1563         result = thermal_register_governors();
1564         if (result)
1565                 goto unregister_netlink;
1566
1567         thermal_class = kzalloc(sizeof(*thermal_class), GFP_KERNEL);
1568         if (!thermal_class) {
1569                 result = -ENOMEM;
1570                 goto unregister_governors;
1571         }
1572
1573         thermal_class->name = "thermal";
1574         thermal_class->dev_release = thermal_release;
1575
1576         result = class_register(thermal_class);
1577         if (result) {
1578                 kfree(thermal_class);
1579                 thermal_class = NULL;
1580                 goto unregister_governors;
1581         }
1582
1583         result = register_pm_notifier(&thermal_pm_nb);
1584         if (result)
1585                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1586                         result);
1587
1588         return 0;
1589
1590 unregister_governors:
1591         thermal_unregister_governors();
1592 unregister_netlink:
1593         thermal_netlink_exit();
1594 error:
1595         mutex_destroy(&thermal_list_lock);
1596         mutex_destroy(&thermal_governor_lock);
1597         return result;
1598 }
1599 postcore_initcall(thermal_init);