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         gov = __find_governor(strim(policy));
 207         if (!gov)
 208                 goto exit;
 209
 210         ret = thermal_set_governor(tz, gov);
 211
 212 exit:
 213         mutex_unlock(&tz->lock);
 214         mutex_unlock(&thermal_governor_lock);
 215
 216         thermal_notify_tz_gov_change(tz->id, policy);
 217
 218         return ret;
 219 }
 220
 221 int thermal_build_list_of_policies(char *buf)
 222 {
 223         struct thermal_governor *pos;
 224         ssize_t count = 0;
 225
 226         mutex_lock(&thermal_governor_lock);
 227
 228         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 229                 count += scnprintf(buf + count, PAGE_SIZE - count, "%s ",
 230                                    pos->name);
 231         }
 232         count += scnprintf(buf + count, PAGE_SIZE - 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, int trip)
 309 {
 310         tz->governor ? tz->governor->throttle(tz, trip) :
 311                        def_governor->throttle(tz, trip);
 312 }
 313
 314 void thermal_zone_device_critical(struct thermal_zone_device *tz)
 315 {
 316         /*
 317          * poweroff_delay_ms must be a carefully profiled positive value.
 318          * Its a must for forced_emergency_poweroff_work to be scheduled.
 319          */
 320         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 321
 322         dev_emerg(&tz->device, "%s: critical temperature reached, "
 323                   "shutting down\n", tz->type);
 324
 325         hw_protection_shutdown("Temperature too high", poweroff_delay_ms);
 326 }
 327 EXPORT_SYMBOL(thermal_zone_device_critical);
 328
 329 static void handle_critical_trips(struct thermal_zone_device *tz,
 330                                   int trip, int trip_temp, enum thermal_trip_type trip_type)
 331 {
 332         /* If we have not crossed the trip_temp, we do not care. */
 333         if (trip_temp <= 0 || tz->temperature < trip_temp)
 334                 return;
 335
 336         trace_thermal_zone_trip(tz, trip, trip_type);
 337
 338         if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
 339                 tz->ops->hot(tz);
 340         else if (trip_type == THERMAL_TRIP_CRITICAL)
 341                 tz->ops->critical(tz);
 342 }
 343
 344 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 345 {
 346         enum thermal_trip_type type;
 347         int trip_temp, hyst = 0;
 348
 349         /* Ignore disabled trip points */
 350         if (test_bit(trip, &tz->trips_disabled))
 351                 return;
 352
 353         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 354         tz->ops->get_trip_type(tz, trip, &type);
 355         if (tz->ops->get_trip_hyst)
 356                 tz->ops->get_trip_hyst(tz, trip, &hyst);
 357
 358         if (tz->last_temperature != THERMAL_TEMP_INVALID) {
 359                 if (tz->last_temperature < trip_temp &&
 360                     tz->temperature >= trip_temp)
 361                         thermal_notify_tz_trip_up(tz->id, trip,
 362                                                   tz->temperature);
 363                 if (tz->last_temperature >= trip_temp &&
 364                     tz->temperature < (trip_temp - hyst))
 365                         thermal_notify_tz_trip_down(tz->id, trip,
 366                                                     tz->temperature);
 367         }
 368
 369         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 370                 handle_critical_trips(tz, trip, trip_temp, type);
 371         else
 372                 handle_non_critical_trips(tz, trip);
 373 }
 374
 375 static void update_temperature(struct thermal_zone_device *tz)
 376 {
 377         int temp, ret;
 378
 379         ret = __thermal_zone_get_temp(tz, &temp);
 380         if (ret) {
 381                 if (ret != -EAGAIN)
 382                         dev_warn(&tz->device,
 383                                  "failed to read out thermal zone (%d)\n",
 384                                  ret);
 385                 return;
 386         }
 387
 388         tz->last_temperature = tz->temperature;
 389         tz->temperature = temp;
 390
 391         trace_thermal_temperature(tz);
 392
 393         thermal_genl_sampling_temp(tz->id, temp);
 394 }
 395
 396 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 397 {
 398         struct thermal_instance *pos;
 399         tz->temperature = THERMAL_TEMP_INVALID;
 400         tz->prev_low_trip = -INT_MAX;
 401         tz->prev_high_trip = INT_MAX;
 402         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 403                 pos->initialized = false;
 404 }
 405
 406 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
 407                                         enum thermal_device_mode mode)
 408 {
 409         int ret = 0;
 410
 411         mutex_lock(&tz->lock);
 412
 413         /* do nothing if mode isn't changing */
 414         if (mode == tz->mode) {
 415                 mutex_unlock(&tz->lock);
 416
 417                 return ret;
 418         }
 419
 420         if (tz->ops->change_mode)
 421                 ret = tz->ops->change_mode(tz, mode);
 422
 423         if (!ret)
 424                 tz->mode = mode;
 425
 426         mutex_unlock(&tz->lock);
 427
 428         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 429
 430         if (mode == THERMAL_DEVICE_ENABLED)
 431                 thermal_notify_tz_enable(tz->id);
 432         else
 433                 thermal_notify_tz_disable(tz->id);
 434
 435         return ret;
 436 }
 437
 438 int thermal_zone_device_enable(struct thermal_zone_device *tz)
 439 {
 440         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
 441 }
 442 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
 443
 444 int thermal_zone_device_disable(struct thermal_zone_device *tz)
 445 {
 446         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
 447 }
 448 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
 449
 450 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
 451 {
 452         lockdep_assert_held(&tz->lock);
 453
 454         return tz->mode == THERMAL_DEVICE_ENABLED;
 455 }
 456
 457 void thermal_zone_device_update(struct thermal_zone_device *tz,
 458                                 enum thermal_notify_event event)
 459 {
 460         int count;
 461
 462         if (atomic_read(&in_suspend))
 463                 return;
 464
 465         if (WARN_ONCE(!tz->ops->get_temp, "'%s' must not be called without "
 466                       "'get_temp' ops set\n", __func__))
 467                 return;
 468
 469         mutex_lock(&tz->lock);
 470
 471         if (!thermal_zone_device_is_enabled(tz))
 472                 goto out;
 473
 474         update_temperature(tz);
 475
 476         __thermal_zone_set_trips(tz);
 477
 478         tz->notify_event = event;
 479
 480         for (count = 0; count < tz->num_trips; count++)
 481                 handle_thermal_trip(tz, count);
 482
 483         monitor_thermal_zone(tz);
 484 out:
 485         mutex_unlock(&tz->lock);
 486 }
 487 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 488
 489 static void thermal_zone_device_check(struct work_struct *work)
 490 {
 491         struct thermal_zone_device *tz = container_of(work, struct
 492                                                       thermal_zone_device,
 493                                                       poll_queue.work);
 494         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 495 }
 496
 497 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
 498                               void *data)
 499 {
 500         struct thermal_governor *gov;
 501         int ret = 0;
 502
 503         mutex_lock(&thermal_governor_lock);
 504         list_for_each_entry(gov, &thermal_governor_list, governor_list) {
 505                 ret = cb(gov, data);
 506                 if (ret)
 507                         break;
 508         }
 509         mutex_unlock(&thermal_governor_lock);
 510
 511         return ret;
 512 }
 513
 514 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
 515                                               void *), void *data)
 516 {
 517         struct thermal_cooling_device *cdev;
 518         int ret = 0;
 519
 520         mutex_lock(&thermal_list_lock);
 521         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 522                 ret = cb(cdev, data);
 523                 if (ret)
 524                         break;
 525         }
 526         mutex_unlock(&thermal_list_lock);
 527
 528         return ret;
 529 }
 530
 531 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
 532                           void *data)
 533 {
 534         struct thermal_zone_device *tz;
 535         int ret = 0;
 536
 537         mutex_lock(&thermal_list_lock);
 538         list_for_each_entry(tz, &thermal_tz_list, node) {
 539                 ret = cb(tz, data);
 540                 if (ret)
 541                         break;
 542         }
 543         mutex_unlock(&thermal_list_lock);
 544
 545         return ret;
 546 }
 547
 548 struct thermal_zone_device *thermal_zone_get_by_id(int id)
 549 {
 550         struct thermal_zone_device *tz, *match = NULL;
 551
 552         mutex_lock(&thermal_list_lock);
 553         list_for_each_entry(tz, &thermal_tz_list, node) {
 554                 if (tz->id == id) {
 555                         match = tz;
 556                         break;
 557                 }
 558         }
 559         mutex_unlock(&thermal_list_lock);
 560
 561         return match;
 562 }
 563
 564 /*
 565  * Device management section: cooling devices, zones devices, and binding
 566  *
 567  * Set of functions provided by the thermal core for:
 568  * - cooling devices lifecycle: registration, unregistration,
 569  *                              binding, and unbinding.
 570  * - thermal zone devices lifecycle: registration, unregistration,
 571  *                                   binding, and unbinding.
 572  */
 573
 574 /**
 575  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 576  * @tz:         pointer to struct thermal_zone_device
 577  * @trip:       indicates which trip point the cooling devices is
 578  *              associated with in this thermal zone.
 579  * @cdev:       pointer to struct thermal_cooling_device
 580  * @upper:      the Maximum cooling state for this trip point.
 581  *              THERMAL_NO_LIMIT means no upper limit,
 582  *              and the cooling device can be in max_state.
 583  * @lower:      the Minimum cooling state can be used for this trip point.
 584  *              THERMAL_NO_LIMIT means no lower limit,
 585  *              and the cooling device can be in cooling state 0.
 586  * @weight:     The weight of the cooling device to be bound to the
 587  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 588  *              default value
 589  *
 590  * This interface function bind a thermal cooling device to the certain trip
 591  * point of a thermal zone device.
 592  * This function is usually called in the thermal zone device .bind callback.
 593  *
 594  * Return: 0 on success, the proper error value otherwise.
 595  */
 596 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 597                                      int trip,
 598                                      struct thermal_cooling_device *cdev,
 599                                      unsigned long upper, unsigned long lower,
 600                                      unsigned int weight)
 601 {
 602         struct thermal_instance *dev;
 603         struct thermal_instance *pos;
 604         struct thermal_zone_device *pos1;
 605         struct thermal_cooling_device *pos2;
 606         unsigned long max_state;
 607         int result, ret;
 608
 609         if (trip >= tz->num_trips || trip < 0)
 610                 return -EINVAL;
 611
 612         list_for_each_entry(pos1, &thermal_tz_list, node) {
 613                 if (pos1 == tz)
 614                         break;
 615         }
 616         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 617                 if (pos2 == cdev)
 618                         break;
 619         }
 620
 621         if (tz != pos1 || cdev != pos2)
 622                 return -EINVAL;
 623
 624         ret = cdev->ops->get_max_state(cdev, &max_state);
 625         if (ret)
 626                 return ret;
 627
 628         /* lower default 0, upper default max_state */
 629         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 630         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 631
 632         if (lower > upper || upper > max_state)
 633                 return -EINVAL;
 634
 635         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 636         if (!dev)
 637                 return -ENOMEM;
 638         dev->tz = tz;
 639         dev->cdev = cdev;
 640         dev->trip = trip;
 641         dev->upper = upper;
 642         dev->lower = lower;
 643         dev->target = THERMAL_NO_TARGET;
 644         dev->weight = weight;
 645
 646         result = ida_alloc(&tz->ida, GFP_KERNEL);
 647         if (result < 0)
 648                 goto free_mem;
 649
 650         dev->id = result;
 651         sprintf(dev->name, "cdev%d", dev->id);
 652         result =
 653             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 654         if (result)
 655                 goto release_ida;
 656
 657         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 658         sysfs_attr_init(&dev->attr.attr);
 659         dev->attr.attr.name = dev->attr_name;
 660         dev->attr.attr.mode = 0444;
 661         dev->attr.show = trip_point_show;
 662         result = device_create_file(&tz->device, &dev->attr);
 663         if (result)
 664                 goto remove_symbol_link;
 665
 666         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 667         sysfs_attr_init(&dev->weight_attr.attr);
 668         dev->weight_attr.attr.name = dev->weight_attr_name;
 669         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 670         dev->weight_attr.show = weight_show;
 671         dev->weight_attr.store = weight_store;
 672         result = device_create_file(&tz->device, &dev->weight_attr);
 673         if (result)
 674                 goto remove_trip_file;
 675
 676         mutex_lock(&tz->lock);
 677         mutex_lock(&cdev->lock);
 678         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 679                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 680                         result = -EEXIST;
 681                         break;
 682                 }
 683         if (!result) {
 684                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 685                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 686                 atomic_set(&tz->need_update, 1);
 687         }
 688         mutex_unlock(&cdev->lock);
 689         mutex_unlock(&tz->lock);
 690
 691         if (!result)
 692                 return 0;
 693
 694         device_remove_file(&tz->device, &dev->weight_attr);
 695 remove_trip_file:
 696         device_remove_file(&tz->device, &dev->attr);
 697 remove_symbol_link:
 698         sysfs_remove_link(&tz->device.kobj, dev->name);
 699 release_ida:
 700         ida_free(&tz->ida, dev->id);
 701 free_mem:
 702         kfree(dev);
 703         return result;
 704 }
 705 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 706
 707 /**
 708  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 709  *                                        thermal zone.
 710  * @tz:         pointer to a struct thermal_zone_device.
 711  * @trip:       indicates which trip point the cooling devices is
 712  *              associated with in this thermal zone.
 713  * @cdev:       pointer to a struct thermal_cooling_device.
 714  *
 715  * This interface function unbind a thermal cooling device from the certain
 716  * trip point of a thermal zone device.
 717  * This function is usually called in the thermal zone device .unbind callback.
 718  *
 719  * Return: 0 on success, the proper error value otherwise.
 720  */
 721 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 722                                        int trip,
 723                                        struct thermal_cooling_device *cdev)
 724 {
 725         struct thermal_instance *pos, *next;
 726
 727         mutex_lock(&tz->lock);
 728         mutex_lock(&cdev->lock);
 729         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 730                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 731                         list_del(&pos->tz_node);
 732                         list_del(&pos->cdev_node);
 733                         mutex_unlock(&cdev->lock);
 734                         mutex_unlock(&tz->lock);
 735                         goto unbind;
 736                 }
 737         }
 738         mutex_unlock(&cdev->lock);
 739         mutex_unlock(&tz->lock);
 740
 741         return -ENODEV;
 742
 743 unbind:
 744         device_remove_file(&tz->device, &pos->weight_attr);
 745         device_remove_file(&tz->device, &pos->attr);
 746         sysfs_remove_link(&tz->device.kobj, pos->name);
 747         ida_free(&tz->ida, pos->id);
 748         kfree(pos);
 749         return 0;
 750 }
 751 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 752
 753 static void thermal_release(struct device *dev)
 754 {
 755         struct thermal_zone_device *tz;
 756         struct thermal_cooling_device *cdev;
 757
 758         if (!strncmp(dev_name(dev), "thermal_zone",
 759                      sizeof("thermal_zone") - 1)) {
 760                 tz = to_thermal_zone(dev);
 761                 thermal_zone_destroy_device_groups(tz);
 762                 kfree(tz);
 763         } else if (!strncmp(dev_name(dev), "cooling_device",
 764                             sizeof("cooling_device") - 1)) {
 765                 cdev = to_cooling_device(dev);
 766                 kfree(cdev);
 767         }
 768 }
 769
 770 static struct class thermal_class = {
 771         .name = "thermal",
 772         .dev_release = thermal_release,
 773 };
 774
 775 static inline
 776 void print_bind_err_msg(struct thermal_zone_device *tz,
 777                         struct thermal_cooling_device *cdev, int ret)
 778 {
 779         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 780                 tz->type, cdev->type, ret);
 781 }
 782
 783 static void __bind(struct thermal_zone_device *tz, int mask,
 784                    struct thermal_cooling_device *cdev,
 785                    unsigned long *limits,
 786                    unsigned int weight)
 787 {
 788         int i, ret;
 789
 790         for (i = 0; i < tz->num_trips; i++) {
 791                 if (mask & (1 << i)) {
 792                         unsigned long upper, lower;
 793
 794                         upper = THERMAL_NO_LIMIT;
 795                         lower = THERMAL_NO_LIMIT;
 796                         if (limits) {
 797                                 lower = limits[i * 2];
 798                                 upper = limits[i * 2 + 1];
 799                         }
 800                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 801                                                                upper, lower,
 802                                                                weight);
 803                         if (ret)
 804                                 print_bind_err_msg(tz, cdev, ret);
 805                 }
 806         }
 807 }
 808
 809 static void bind_cdev(struct thermal_cooling_device *cdev)
 810 {
 811         int i, ret;
 812         const struct thermal_zone_params *tzp;
 813         struct thermal_zone_device *pos = NULL;
 814
 815         mutex_lock(&thermal_list_lock);
 816
 817         list_for_each_entry(pos, &thermal_tz_list, node) {
 818                 if (!pos->tzp && !pos->ops->bind)
 819                         continue;
 820
 821                 if (pos->ops->bind) {
 822                         ret = pos->ops->bind(pos, cdev);
 823                         if (ret)
 824                                 print_bind_err_msg(pos, cdev, ret);
 825                         continue;
 826                 }
 827
 828                 tzp = pos->tzp;
 829                 if (!tzp || !tzp->tbp)
 830                         continue;
 831
 832                 for (i = 0; i < tzp->num_tbps; i++) {
 833                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 834                                 continue;
 835                         if (tzp->tbp[i].match(pos, cdev))
 836                                 continue;
 837                         tzp->tbp[i].cdev = cdev;
 838                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 839                                tzp->tbp[i].binding_limits,
 840                                tzp->tbp[i].weight);
 841                 }
 842         }
 843
 844         mutex_unlock(&thermal_list_lock);
 845 }
 846
 847 /**
 848  * __thermal_cooling_device_register() - register a new thermal cooling device
 849  * @np:         a pointer to a device tree node.
 850  * @type:       the thermal cooling device type.
 851  * @devdata:    device private data.
 852  * @ops:                standard thermal cooling devices callbacks.
 853  *
 854  * This interface function adds a new thermal cooling device (fan/processor/...)
 855  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 856  * to all the thermal zone devices registered at the same time.
 857  * It also gives the opportunity to link the cooling device to a device tree
 858  * node, so that it can be bound to a thermal zone created out of device tree.
 859  *
 860  * Return: a pointer to the created struct thermal_cooling_device or an
 861  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 862  */
 863 static struct thermal_cooling_device *
 864 __thermal_cooling_device_register(struct device_node *np,
 865                                   const char *type, void *devdata,
 866                                   const struct thermal_cooling_device_ops *ops)
 867 {
 868         struct thermal_cooling_device *cdev;
 869         struct thermal_zone_device *pos = NULL;
 870         int id, ret;
 871
 872         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 873             !ops->set_cur_state)
 874                 return ERR_PTR(-EINVAL);
 875
 876         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 877         if (!cdev)
 878                 return ERR_PTR(-ENOMEM);
 879
 880         ret = ida_alloc(&thermal_cdev_ida, GFP_KERNEL);
 881         if (ret < 0)
 882                 goto out_kfree_cdev;
 883         cdev->id = ret;
 884         id = ret;
 885
 886         cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
 887         if (!cdev->type) {
 888                 ret = -ENOMEM;
 889                 goto out_ida_remove;
 890         }
 891
 892         mutex_init(&cdev->lock);
 893         INIT_LIST_HEAD(&cdev->thermal_instances);
 894         cdev->np = np;
 895         cdev->ops = ops;
 896         cdev->updated = false;
 897         cdev->device.class = &thermal_class;
 898         cdev->devdata = devdata;
 899         thermal_cooling_device_setup_sysfs(cdev);
 900         ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 901         if (ret) {
 902                 thermal_cooling_device_destroy_sysfs(cdev);
 903                 goto out_kfree_type;
 904         }
 905         ret = device_register(&cdev->device);
 906         if (ret)
 907                 goto out_kfree_type;
 908
 909         /* Add 'this' new cdev to the global cdev list */
 910         mutex_lock(&thermal_list_lock);
 911         list_add(&cdev->node, &thermal_cdev_list);
 912         mutex_unlock(&thermal_list_lock);
 913
 914         /* Update binding information for 'this' new cdev */
 915         bind_cdev(cdev);
 916
 917         mutex_lock(&thermal_list_lock);
 918         list_for_each_entry(pos, &thermal_tz_list, node)
 919                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
 920                         thermal_zone_device_update(pos,
 921                                                    THERMAL_EVENT_UNSPECIFIED);
 922         mutex_unlock(&thermal_list_lock);
 923
 924         return cdev;
 925
 926 out_kfree_type:
 927         thermal_cooling_device_destroy_sysfs(cdev);
 928         kfree(cdev->type);
 929         put_device(&cdev->device);
 930         cdev = NULL;
 931 out_ida_remove:
 932         ida_free(&thermal_cdev_ida, id);
 933 out_kfree_cdev:
 934         kfree(cdev);
 935         return ERR_PTR(ret);
 936 }
 937
 938 /**
 939  * thermal_cooling_device_register() - register a new thermal cooling device
 940  * @type:       the thermal cooling device type.
 941  * @devdata:    device private data.
 942  * @ops:                standard thermal cooling devices callbacks.
 943  *
 944  * This interface function adds a new thermal cooling device (fan/processor/...)
 945  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 946  * to all the thermal zone devices registered at the same time.
 947  *
 948  * Return: a pointer to the created struct thermal_cooling_device or an
 949  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 950  */
 951 struct thermal_cooling_device *
 952 thermal_cooling_device_register(const char *type, void *devdata,
 953                                 const struct thermal_cooling_device_ops *ops)
 954 {
 955         return __thermal_cooling_device_register(NULL, type, devdata, ops);
 956 }
 957 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
 958
 959 /**
 960  * thermal_of_cooling_device_register() - register an OF thermal cooling device
 961  * @np:         a pointer to a device tree node.
 962  * @type:       the thermal cooling device type.
 963  * @devdata:    device private data.
 964  * @ops:                standard thermal cooling devices callbacks.
 965  *
 966  * This function will register a cooling device with device tree node reference.
 967  * This interface function adds a new thermal cooling device (fan/processor/...)
 968  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 969  * to all the thermal zone devices registered at the same time.
 970  *
 971  * Return: a pointer to the created struct thermal_cooling_device or an
 972  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 973  */
 974 struct thermal_cooling_device *
 975 thermal_of_cooling_device_register(struct device_node *np,
 976                                    const char *type, void *devdata,
 977                                    const struct thermal_cooling_device_ops *ops)
 978 {
 979         return __thermal_cooling_device_register(np, type, devdata, ops);
 980 }
 981 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
 982
 983 static void thermal_cooling_device_release(struct device *dev, void *res)
 984 {
 985         thermal_cooling_device_unregister(
 986                                 *(struct thermal_cooling_device **)res);
 987 }
 988
 989 /**
 990  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
 991  *                                             device
 992  * @dev:        a valid struct device pointer of a sensor device.
 993  * @np:         a pointer to a device tree node.
 994  * @type:       the thermal cooling device type.
 995  * @devdata:    device private data.
 996  * @ops:        standard thermal cooling devices callbacks.
 997  *
 998  * This function will register a cooling device with device tree node reference.
 999  * This interface function adds a new thermal cooling device (fan/processor/...)
1000  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1001  * to all the thermal zone devices registered at the same time.
1002  *
1003  * Return: a pointer to the created struct thermal_cooling_device or an
1004  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1005  */
1006 struct thermal_cooling_device *
1007 devm_thermal_of_cooling_device_register(struct device *dev,
1008                                 struct device_node *np,
1009                                 char *type, void *devdata,
1010                                 const struct thermal_cooling_device_ops *ops)
1011 {
1012         struct thermal_cooling_device **ptr, *tcd;
1013
1014         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1015                            GFP_KERNEL);
1016         if (!ptr)
1017                 return ERR_PTR(-ENOMEM);
1018
1019         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1020         if (IS_ERR(tcd)) {
1021                 devres_free(ptr);
1022                 return tcd;
1023         }
1024
1025         *ptr = tcd;
1026         devres_add(dev, ptr);
1027
1028         return tcd;
1029 }
1030 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1031
1032 static void __unbind(struct thermal_zone_device *tz, int mask,
1033                      struct thermal_cooling_device *cdev)
1034 {
1035         int i;
1036
1037         for (i = 0; i < tz->num_trips; i++)
1038                 if (mask & (1 << i))
1039                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1040 }
1041
1042 /**
1043  * thermal_cooling_device_unregister - removes a thermal cooling device
1044  * @cdev:       the thermal cooling device to remove.
1045  *
1046  * thermal_cooling_device_unregister() must be called when a registered
1047  * thermal cooling device is no longer needed.
1048  */
1049 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1050 {
1051         int i;
1052         const struct thermal_zone_params *tzp;
1053         struct thermal_zone_device *tz;
1054         struct thermal_cooling_device *pos = NULL;
1055
1056         if (!cdev)
1057                 return;
1058
1059         mutex_lock(&thermal_list_lock);
1060         list_for_each_entry(pos, &thermal_cdev_list, node)
1061                 if (pos == cdev)
1062                         break;
1063         if (pos != cdev) {
1064                 /* thermal cooling device not found */
1065                 mutex_unlock(&thermal_list_lock);
1066                 return;
1067         }
1068         list_del(&cdev->node);
1069
1070         /* Unbind all thermal zones associated with 'this' cdev */
1071         list_for_each_entry(tz, &thermal_tz_list, node) {
1072                 if (tz->ops->unbind) {
1073                         tz->ops->unbind(tz, cdev);
1074                         continue;
1075                 }
1076
1077                 if (!tz->tzp || !tz->tzp->tbp)
1078                         continue;
1079
1080                 tzp = tz->tzp;
1081                 for (i = 0; i < tzp->num_tbps; i++) {
1082                         if (tzp->tbp[i].cdev == cdev) {
1083                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1084                                 tzp->tbp[i].cdev = NULL;
1085                         }
1086                 }
1087         }
1088
1089         mutex_unlock(&thermal_list_lock);
1090
1091         ida_free(&thermal_cdev_ida, cdev->id);
1092         device_del(&cdev->device);
1093         thermal_cooling_device_destroy_sysfs(cdev);
1094         kfree(cdev->type);
1095         put_device(&cdev->device);
1096 }
1097 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1098
1099 static void bind_tz(struct thermal_zone_device *tz)
1100 {
1101         int i, ret;
1102         struct thermal_cooling_device *pos = NULL;
1103         const struct thermal_zone_params *tzp = tz->tzp;
1104
1105         if (!tzp && !tz->ops->bind)
1106                 return;
1107
1108         mutex_lock(&thermal_list_lock);
1109
1110         /* If there is ops->bind, try to use ops->bind */
1111         if (tz->ops->bind) {
1112                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1113                         ret = tz->ops->bind(tz, pos);
1114                         if (ret)
1115                                 print_bind_err_msg(tz, pos, ret);
1116                 }
1117                 goto exit;
1118         }
1119
1120         if (!tzp || !tzp->tbp)
1121                 goto exit;
1122
1123         list_for_each_entry(pos, &thermal_cdev_list, node) {
1124                 for (i = 0; i < tzp->num_tbps; i++) {
1125                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1126                                 continue;
1127                         if (tzp->tbp[i].match(tz, pos))
1128                                 continue;
1129                         tzp->tbp[i].cdev = pos;
1130                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1131                                tzp->tbp[i].binding_limits,
1132                                tzp->tbp[i].weight);
1133                 }
1134         }
1135 exit:
1136         mutex_unlock(&thermal_list_lock);
1137 }
1138
1139 static void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms)
1140 {
1141         *delay_jiffies = msecs_to_jiffies(delay_ms);
1142         if (delay_ms > 1000)
1143                 *delay_jiffies = round_jiffies(*delay_jiffies);
1144 }
1145
1146 /**
1147  * thermal_zone_device_register_with_trips() - register a new thermal zone device
1148  * @type:       the thermal zone device type
1149  * @trips:      a pointer to an array of thermal trips
1150  * @num_trips:  the number of trip points the thermal zone support
1151  * @mask:       a bit string indicating the writeablility of trip points
1152  * @devdata:    private device data
1153  * @ops:        standard thermal zone device callbacks
1154  * @tzp:        thermal zone platform parameters
1155  * @passive_delay: number of milliseconds to wait between polls when
1156  *                 performing passive cooling
1157  * @polling_delay: number of milliseconds to wait between polls when checking
1158  *                 whether trip points have been crossed (0 for interrupt
1159  *                 driven systems)
1160  *
1161  * This interface function adds a new thermal zone device (sensor) to
1162  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1163  * thermal cooling devices registered at the same time.
1164  * thermal_zone_device_unregister() must be called when the device is no
1165  * longer needed. The passive cooling depends on the .get_trend() return value.
1166  *
1167  * Return: a pointer to the created struct thermal_zone_device or an
1168  * in case of error, an ERR_PTR. Caller must check return value with
1169  * IS_ERR*() helpers.
1170  */
1171 struct thermal_zone_device *
1172 thermal_zone_device_register_with_trips(const char *type, struct thermal_trip *trips, int num_trips, int mask,
1173                                         void *devdata, struct thermal_zone_device_ops *ops,
1174                                         struct thermal_zone_params *tzp, int passive_delay,
1175                                         int polling_delay)
1176 {
1177         struct thermal_zone_device *tz;
1178         enum thermal_trip_type trip_type;
1179         int trip_temp;
1180         int id;
1181         int result;
1182         int count;
1183         struct thermal_governor *governor;
1184
1185         if (!type || strlen(type) == 0) {
1186                 pr_err("No thermal zone type defined\n");
1187                 return ERR_PTR(-EINVAL);
1188         }
1189
1190         if (strlen(type) >= THERMAL_NAME_LENGTH) {
1191                 pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1192                        type, THERMAL_NAME_LENGTH);
1193                 return ERR_PTR(-EINVAL);
1194         }
1195
1196         /*
1197          * Max trip count can't exceed 31 as the "mask >> num_trips" condition.
1198          * For example, shifting by 32 will result in compiler warning:
1199          * warning: right shift count >= width of type [-Wshift-count- overflow]
1200          *
1201          * Also "mask >> num_trips" will always be true with 32 bit shift.
1202          * E.g. mask = 0x80000000 for trip id 31 to be RW. Then
1203          * mask >> 32 = 0x80000000
1204          * This will result in failure for the below condition.
1205          *
1206          * Check will be true when the bit 31 of the mask is set.
1207          * 32 bit shift will cause overflow of 4 byte integer.
1208          */
1209         if (num_trips > (BITS_PER_TYPE(int) - 1) || num_trips < 0 || mask >> num_trips) {
1210                 pr_err("Incorrect number of thermal trips\n");
1211                 return ERR_PTR(-EINVAL);
1212         }
1213
1214         if (!ops) {
1215                 pr_err("Thermal zone device ops not defined\n");
1216                 return ERR_PTR(-EINVAL);
1217         }
1218
1219         if (num_trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1220                 return ERR_PTR(-EINVAL);
1221
1222         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1223         if (!tz)
1224                 return ERR_PTR(-ENOMEM);
1225
1226         INIT_LIST_HEAD(&tz->thermal_instances);
1227         ida_init(&tz->ida);
1228         mutex_init(&tz->lock);
1229         id = ida_alloc(&thermal_tz_ida, GFP_KERNEL);
1230         if (id < 0) {
1231                 result = id;
1232                 goto free_tz;
1233         }
1234
1235         tz->id = id;
1236         strscpy(tz->type, type, sizeof(tz->type));
1237
1238         if (!ops->critical)
1239                 ops->critical = thermal_zone_device_critical;
1240
1241         tz->ops = ops;
1242         tz->tzp = tzp;
1243         tz->device.class = &thermal_class;
1244         tz->devdata = devdata;
1245         tz->trips = trips;
1246         tz->num_trips = num_trips;
1247
1248         thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1249         thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1250
1251         /* sys I/F */
1252         /* Add nodes that are always present via .groups */
1253         result = thermal_zone_create_device_groups(tz, mask);
1254         if (result)
1255                 goto remove_id;
1256
1257         /* A new thermal zone needs to be updated anyway. */
1258         atomic_set(&tz->need_update, 1);
1259
1260         result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1261         if (result) {
1262                 thermal_zone_destroy_device_groups(tz);
1263                 goto remove_id;
1264         }
1265         result = device_register(&tz->device);
1266         if (result)
1267                 goto release_device;
1268
1269         for (count = 0; count < num_trips; count++) {
1270                 if (tz->ops->get_trip_type(tz, count, &trip_type) ||
1271                     tz->ops->get_trip_temp(tz, count, &trip_temp) ||
1272                     !trip_temp)
1273                         set_bit(count, &tz->trips_disabled);
1274         }
1275
1276         /* Update 'this' zone's governor information */
1277         mutex_lock(&thermal_governor_lock);
1278
1279         if (tz->tzp)
1280                 governor = __find_governor(tz->tzp->governor_name);
1281         else
1282                 governor = def_governor;
1283
1284         result = thermal_set_governor(tz, governor);
1285         if (result) {
1286                 mutex_unlock(&thermal_governor_lock);
1287                 goto unregister;
1288         }
1289
1290         mutex_unlock(&thermal_governor_lock);
1291
1292         if (!tz->tzp || !tz->tzp->no_hwmon) {
1293                 result = thermal_add_hwmon_sysfs(tz);
1294                 if (result)
1295                         goto unregister;
1296         }
1297
1298         mutex_lock(&thermal_list_lock);
1299         list_add_tail(&tz->node, &thermal_tz_list);
1300         mutex_unlock(&thermal_list_lock);
1301
1302         /* Bind cooling devices for this zone */
1303         bind_tz(tz);
1304
1305         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1306
1307         thermal_zone_device_init(tz);
1308         /* Update the new thermal zone and mark it as already updated. */
1309         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1310                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1311
1312         thermal_notify_tz_create(tz->id, tz->type);
1313
1314         return tz;
1315
1316 unregister:
1317         device_del(&tz->device);
1318 release_device:
1319         put_device(&tz->device);
1320         tz = NULL;
1321 remove_id:
1322         ida_free(&thermal_tz_ida, id);
1323 free_tz:
1324         kfree(tz);
1325         return ERR_PTR(result);
1326 }
1327 EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1328
1329 struct thermal_zone_device *thermal_zone_device_register(const char *type, int ntrips, int mask,
1330                                                          void *devdata, struct thermal_zone_device_ops *ops,
1331                                                          struct thermal_zone_params *tzp, int passive_delay,
1332                                                          int polling_delay)
1333 {
1334         return thermal_zone_device_register_with_trips(type, NULL, ntrips, mask,
1335                                                        devdata, ops, tzp,
1336                                                        passive_delay, polling_delay);
1337 }
1338 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1339
1340 /**
1341  * thermal_zone_device_unregister - removes the registered thermal zone device
1342  * @tz: the thermal zone device to remove
1343  */
1344 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1345 {
1346         int i, tz_id;
1347         const struct thermal_zone_params *tzp;
1348         struct thermal_cooling_device *cdev;
1349         struct thermal_zone_device *pos = NULL;
1350
1351         if (!tz)
1352                 return;
1353
1354         tzp = tz->tzp;
1355         tz_id = tz->id;
1356
1357         mutex_lock(&thermal_list_lock);
1358         list_for_each_entry(pos, &thermal_tz_list, node)
1359                 if (pos == tz)
1360                         break;
1361         if (pos != tz) {
1362                 /* thermal zone device not found */
1363                 mutex_unlock(&thermal_list_lock);
1364                 return;
1365         }
1366         list_del(&tz->node);
1367
1368         /* Unbind all cdevs associated with 'this' thermal zone */
1369         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1370                 if (tz->ops->unbind) {
1371                         tz->ops->unbind(tz, cdev);
1372                         continue;
1373                 }
1374
1375                 if (!tzp || !tzp->tbp)
1376                         break;
1377
1378                 for (i = 0; i < tzp->num_tbps; i++) {
1379                         if (tzp->tbp[i].cdev == cdev) {
1380                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1381                                 tzp->tbp[i].cdev = NULL;
1382                         }
1383                 }
1384         }
1385
1386         mutex_unlock(&thermal_list_lock);
1387
1388         cancel_delayed_work_sync(&tz->poll_queue);
1389
1390         thermal_set_governor(tz, NULL);
1391
1392         thermal_remove_hwmon_sysfs(tz);
1393         ida_free(&thermal_tz_ida, tz->id);
1394         ida_destroy(&tz->ida);
1395         mutex_destroy(&tz->lock);
1396         device_unregister(&tz->device);
1397
1398         thermal_notify_tz_delete(tz_id);
1399 }
1400 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1401
1402 /**
1403  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1404  * @name: thermal zone name to fetch the temperature
1405  *
1406  * When only one zone is found with the passed name, returns a reference to it.
1407  *
1408  * Return: On success returns a reference to an unique thermal zone with
1409  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1410  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1411  */
1412 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1413 {
1414         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1415         unsigned int found = 0;
1416
1417         if (!name)
1418                 goto exit;
1419
1420         mutex_lock(&thermal_list_lock);
1421         list_for_each_entry(pos, &thermal_tz_list, node)
1422                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1423                         found++;
1424                         ref = pos;
1425                 }
1426         mutex_unlock(&thermal_list_lock);
1427
1428         /* nothing has been found, thus an error code for it */
1429         if (found == 0)
1430                 ref = ERR_PTR(-ENODEV);
1431         else if (found > 1)
1432         /* Success only when an unique zone is found */
1433                 ref = ERR_PTR(-EEXIST);
1434
1435 exit:
1436         return ref;
1437 }
1438 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1439
1440 static int thermal_pm_notify(struct notifier_block *nb,
1441                              unsigned long mode, void *_unused)
1442 {
1443         struct thermal_zone_device *tz;
1444
1445         switch (mode) {
1446         case PM_HIBERNATION_PREPARE:
1447         case PM_RESTORE_PREPARE:
1448         case PM_SUSPEND_PREPARE:
1449                 atomic_set(&in_suspend, 1);
1450                 break;
1451         case PM_POST_HIBERNATION:
1452         case PM_POST_RESTORE:
1453         case PM_POST_SUSPEND:
1454                 atomic_set(&in_suspend, 0);
1455                 list_for_each_entry(tz, &thermal_tz_list, node) {
1456                         thermal_zone_device_init(tz);
1457                         thermal_zone_device_update(tz,
1458                                                    THERMAL_EVENT_UNSPECIFIED);
1459                 }
1460                 break;
1461         default:
1462                 break;
1463         }
1464         return 0;
1465 }
1466
1467 static struct notifier_block thermal_pm_nb = {
1468         .notifier_call = thermal_pm_notify,
1469 };
1470
1471 static int __init thermal_init(void)
1472 {
1473         int result;
1474
1475         result = thermal_netlink_init();
1476         if (result)
1477                 goto error;
1478
1479         result = thermal_register_governors();
1480         if (result)
1481                 goto error;
1482
1483         result = class_register(&thermal_class);
1484         if (result)
1485                 goto unregister_governors;
1486
1487         result = register_pm_notifier(&thermal_pm_nb);
1488         if (result)
1489                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1490                         result);
1491
1492         return 0;
1493
1494 unregister_governors:
1495         thermal_unregister_governors();
1496 error:
1497         ida_destroy(&thermal_tz_ida);
1498         ida_destroy(&thermal_cdev_ida);
1499         mutex_destroy(&thermal_list_lock);
1500         mutex_destroy(&thermal_governor_lock);
1501         return result;
1502 }
1503 postcore_initcall(thermal_init);