drivers/thermal/thermal_core.c

   1 /*
   2  *  thermal.c - Generic Thermal Management Sysfs support.
   3  *
   4  *  Copyright (C) 2008 Intel Corp
   5  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   6  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; version 2 of the License.
  11  */
  12
  13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15 #include <linux/module.h>
  16 #include <linux/device.h>
  17 #include <linux/err.h>
  18 #include <linux/slab.h>
  19 #include <linux/kdev_t.h>
  20 #include <linux/idr.h>
  21 #include <linux/thermal.h>
  22 #include <linux/reboot.h>
  23 #include <linux/string.h>
  24 #include <linux/of.h>
  25 #include <net/netlink.h>
  26 #include <net/genetlink.h>
  27 #include <linux/suspend.h>
  28
  29 #define CREATE_TRACE_POINTS
  30 #include <trace/events/thermal.h>
  31
  32 #include "thermal_core.h"
  33 #include "thermal_hwmon.h"
  34
  35 MODULE_AUTHOR("Zhang Rui");
  36 MODULE_DESCRIPTION("Generic thermal management sysfs support");
  37 MODULE_LICENSE("GPL v2");
  38
  39 static DEFINE_IDR(thermal_tz_idr);
  40 static DEFINE_IDR(thermal_cdev_idr);
  41 static DEFINE_MUTEX(thermal_idr_lock);
  42
  43 static LIST_HEAD(thermal_tz_list);
  44 static LIST_HEAD(thermal_cdev_list);
  45 static LIST_HEAD(thermal_governor_list);
  46
  47 static DEFINE_MUTEX(thermal_list_lock);
  48 static DEFINE_MUTEX(thermal_governor_lock);
  49
  50 static atomic_t in_suspend;
  51
  52 static struct thermal_governor *def_governor;
  53
  54 /*
  55  * Governor section: set of functions to handle thermal governors
  56  *
  57  * Functions to help in the life cycle of thermal governors within
  58  * the thermal core and by the thermal governor code.
  59  */
  60
  61 static struct thermal_governor *__find_governor(const char *name)
  62 {
  63         struct thermal_governor *pos;
  64
  65         if (!name || !name[0])
  66                 return def_governor;
  67
  68         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  69                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  70                         return pos;
  71
  72         return NULL;
  73 }
  74
  75 /**
  76  * bind_previous_governor() - bind the previous governor of the thermal zone
  77  * @tz:         a valid pointer to a struct thermal_zone_device
  78  * @failed_gov_name:    the name of the governor that failed to register
  79  *
  80  * Register the previous governor of the thermal zone after a new
  81  * governor has failed to be bound.
  82  */
  83 static void bind_previous_governor(struct thermal_zone_device *tz,
  84                                    const char *failed_gov_name)
  85 {
  86         if (tz->governor && tz->governor->bind_to_tz) {
  87                 if (tz->governor->bind_to_tz(tz)) {
  88                         dev_err(&tz->device,
  89                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  90                                 failed_gov_name, tz->governor->name, tz->type);
  91                         tz->governor = NULL;
  92                 }
  93         }
  94 }
  95
  96 /**
  97  * thermal_set_governor() - Switch to another governor
  98  * @tz:         a valid pointer to a struct thermal_zone_device
  99  * @new_gov:    pointer to the new governor
 100  *
 101  * Change the governor of thermal zone @tz.
 102  *
 103  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
 104  */
 105 static int thermal_set_governor(struct thermal_zone_device *tz,
 106                                 struct thermal_governor *new_gov)
 107 {
 108         int ret = 0;
 109
 110         if (tz->governor && tz->governor->unbind_from_tz)
 111                 tz->governor->unbind_from_tz(tz);
 112
 113         if (new_gov && new_gov->bind_to_tz) {
 114                 ret = new_gov->bind_to_tz(tz);
 115                 if (ret) {
 116                         bind_previous_governor(tz, new_gov->name);
 117
 118                         return ret;
 119                 }
 120         }
 121
 122         tz->governor = new_gov;
 123
 124         return ret;
 125 }
 126
 127 int thermal_register_governor(struct thermal_governor *governor)
 128 {
 129         int err;
 130         const char *name;
 131         struct thermal_zone_device *pos;
 132
 133         if (!governor)
 134                 return -EINVAL;
 135
 136         mutex_lock(&thermal_governor_lock);
 137
 138         err = -EBUSY;
 139         if (!__find_governor(governor->name)) {
 140                 bool match_default;
 141
 142                 err = 0;
 143                 list_add(&governor->governor_list, &thermal_governor_list);
 144                 match_default = !strncmp(governor->name,
 145                                          DEFAULT_THERMAL_GOVERNOR,
 146                                          THERMAL_NAME_LENGTH);
 147
 148                 if (!def_governor && match_default)
 149                         def_governor = governor;
 150         }
 151
 152         mutex_lock(&thermal_list_lock);
 153
 154         list_for_each_entry(pos, &thermal_tz_list, node) {
 155                 /*
 156                  * only thermal zones with specified tz->tzp->governor_name
 157                  * may run with tz->govenor unset
 158                  */
 159                 if (pos->governor)
 160                         continue;
 161
 162                 name = pos->tzp->governor_name;
 163
 164                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 165                         int ret;
 166
 167                         ret = thermal_set_governor(pos, governor);
 168                         if (ret)
 169                                 dev_err(&pos->device,
 170                                         "Failed to set governor %s for thermal zone %s: %d\n",
 171                                         governor->name, pos->type, ret);
 172                 }
 173         }
 174
 175         mutex_unlock(&thermal_list_lock);
 176         mutex_unlock(&thermal_governor_lock);
 177
 178         return err;
 179 }
 180
 181 void thermal_unregister_governor(struct thermal_governor *governor)
 182 {
 183         struct thermal_zone_device *pos;
 184
 185         if (!governor)
 186                 return;
 187
 188         mutex_lock(&thermal_governor_lock);
 189
 190         if (!__find_governor(governor->name))
 191                 goto exit;
 192
 193         mutex_lock(&thermal_list_lock);
 194
 195         list_for_each_entry(pos, &thermal_tz_list, node) {
 196                 if (!strncasecmp(pos->governor->name, governor->name,
 197                                  THERMAL_NAME_LENGTH))
 198                         thermal_set_governor(pos, NULL);
 199         }
 200
 201         mutex_unlock(&thermal_list_lock);
 202         list_del(&governor->governor_list);
 203 exit:
 204         mutex_unlock(&thermal_governor_lock);
 205 }
 206
 207 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 208                                    char *policy)
 209 {
 210         struct thermal_governor *gov;
 211         int ret = -EINVAL;
 212
 213         mutex_lock(&thermal_governor_lock);
 214         mutex_lock(&tz->lock);
 215
 216         gov = __find_governor(strim(policy));
 217         if (!gov)
 218                 goto exit;
 219
 220         ret = thermal_set_governor(tz, gov);
 221
 222 exit:
 223         mutex_unlock(&tz->lock);
 224         mutex_unlock(&thermal_governor_lock);
 225
 226         return ret;
 227 }
 228
 229 int thermal_build_list_of_policies(char *buf)
 230 {
 231         struct thermal_governor *pos;
 232         ssize_t count = 0;
 233         ssize_t size = PAGE_SIZE;
 234
 235         mutex_lock(&thermal_governor_lock);
 236
 237         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 238                 size = PAGE_SIZE - count;
 239                 count += scnprintf(buf + count, size, "%s ", pos->name);
 240         }
 241         count += scnprintf(buf + count, size, "\n");
 242
 243         mutex_unlock(&thermal_governor_lock);
 244
 245         return count;
 246 }
 247
 248 static int __init thermal_register_governors(void)
 249 {
 250         int result;
 251
 252         result = thermal_gov_step_wise_register();
 253         if (result)
 254                 return result;
 255
 256         result = thermal_gov_fair_share_register();
 257         if (result)
 258                 return result;
 259
 260         result = thermal_gov_bang_bang_register();
 261         if (result)
 262                 return result;
 263
 264         result = thermal_gov_user_space_register();
 265         if (result)
 266                 return result;
 267
 268         return thermal_gov_power_allocator_register();
 269 }
 270
 271 static void thermal_unregister_governors(void)
 272 {
 273         thermal_gov_step_wise_unregister();
 274         thermal_gov_fair_share_unregister();
 275         thermal_gov_bang_bang_unregister();
 276         thermal_gov_user_space_unregister();
 277         thermal_gov_power_allocator_unregister();
 278 }
 279
 280 /*
 281  * Zone update section: main control loop applied to each zone while monitoring
 282  *
 283  * in polling mode. The monitoring is done using a workqueue.
 284  * Same update may be done on a zone by calling thermal_zone_device_update().
 285  *
 286  * An update means:
 287  * - Non-critical trips will invoke the governor responsible for that zone;
 288  * - Hot trips will produce a notification to userspace;
 289  * - Critical trip point will cause a system shutdown.
 290  */
 291 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 292                                             int delay)
 293 {
 294         if (delay > 1000)
 295                 mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 296                                  round_jiffies(msecs_to_jiffies(delay)));
 297         else if (delay)
 298                 mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 299                                  msecs_to_jiffies(delay));
 300         else
 301                 cancel_delayed_work(&tz->poll_queue);
 302 }
 303
 304 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 305 {
 306         mutex_lock(&tz->lock);
 307
 308         if (tz->passive)
 309                 thermal_zone_device_set_polling(tz, tz->passive_delay);
 310         else if (tz->polling_delay)
 311                 thermal_zone_device_set_polling(tz, tz->polling_delay);
 312         else
 313                 thermal_zone_device_set_polling(tz, 0);
 314
 315         mutex_unlock(&tz->lock);
 316 }
 317
 318 static void handle_non_critical_trips(struct thermal_zone_device *tz,
 319                                       int trip,
 320                                       enum thermal_trip_type trip_type)
 321 {
 322         tz->governor ? tz->governor->throttle(tz, trip) :
 323                        def_governor->throttle(tz, trip);
 324 }
 325
 326 static void handle_critical_trips(struct thermal_zone_device *tz,
 327                                   int trip, enum thermal_trip_type trip_type)
 328 {
 329         int trip_temp;
 330
 331         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 332
 333         /* If we have not crossed the trip_temp, we do not care. */
 334         if (trip_temp <= 0 || tz->temperature < trip_temp)
 335                 return;
 336
 337         trace_thermal_zone_trip(tz, trip, trip_type);
 338
 339         if (tz->ops->notify)
 340                 tz->ops->notify(tz, trip, trip_type);
 341
 342         if (trip_type == THERMAL_TRIP_CRITICAL) {
 343                 dev_emerg(&tz->device,
 344                           "critical temperature reached(%d C),shutting down\n",
 345                           tz->temperature / 1000);
 346                 orderly_poweroff(true);
 347         }
 348 }
 349
 350 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 351 {
 352         enum thermal_trip_type type;
 353
 354         /* Ignore disabled trip points */
 355         if (test_bit(trip, &tz->trips_disabled))
 356                 return;
 357
 358         tz->ops->get_trip_type(tz, trip, &type);
 359
 360         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 361                 handle_critical_trips(tz, trip, type);
 362         else
 363                 handle_non_critical_trips(tz, trip, type);
 364         /*
 365          * Alright, we handled this trip successfully.
 366          * So, start monitoring again.
 367          */
 368         monitor_thermal_zone(tz);
 369 }
 370
 371 static void update_temperature(struct thermal_zone_device *tz)
 372 {
 373         int temp, ret;
 374
 375         ret = thermal_zone_get_temp(tz, &temp);
 376         if (ret) {
 377                 if (ret != -EAGAIN)
 378                         dev_warn(&tz->device,
 379                                  "failed to read out thermal zone (%d)\n",
 380                                  ret);
 381                 return;
 382         }
 383
 384         mutex_lock(&tz->lock);
 385         tz->last_temperature = tz->temperature;
 386         tz->temperature = temp;
 387         mutex_unlock(&tz->lock);
 388
 389         trace_thermal_temperature(tz);
 390         if (tz->last_temperature == THERMAL_TEMP_INVALID)
 391                 dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n",
 392                         tz->temperature);
 393         else
 394                 dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
 395                         tz->last_temperature, tz->temperature);
 396 }
 397
 398 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 399 {
 400         struct thermal_instance *pos;
 401
 402         tz->temperature = THERMAL_TEMP_INVALID;
 403         tz->passive = 0;
 404         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 405                 pos->initialized = false;
 406 }
 407
 408 void thermal_zone_device_update(struct thermal_zone_device *tz,
 409                                 enum thermal_notify_event event)
 410 {
 411         int count;
 412
 413         if (atomic_read(&in_suspend))
 414                 return;
 415
 416         if (!tz->ops->get_temp)
 417                 return;
 418
 419         update_temperature(tz);
 420
 421         thermal_zone_set_trips(tz);
 422
 423         tz->notify_event = event;
 424
 425         for (count = 0; count < tz->trips; count++)
 426                 handle_thermal_trip(tz, count);
 427 }
 428 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 429
 430 /**
 431  * thermal_notify_framework - Sensor drivers use this API to notify framework
 432  * @tz:         thermal zone device
 433  * @trip:       indicates which trip point has been crossed
 434  *
 435  * This function handles the trip events from sensor drivers. It starts
 436  * throttling the cooling devices according to the policy configured.
 437  * For CRITICAL and HOT trip points, this notifies the respective drivers,
 438  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
 439  * The throttling policy is based on the configured platform data; if no
 440  * platform data is provided, this uses the step_wise throttling policy.
 441  */
 442 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
 443 {
 444         handle_thermal_trip(tz, trip);
 445 }
 446 EXPORT_SYMBOL_GPL(thermal_notify_framework);
 447
 448 static void thermal_zone_device_check(struct work_struct *work)
 449 {
 450         struct thermal_zone_device *tz = container_of(work, struct
 451                                                       thermal_zone_device,
 452                                                       poll_queue.work);
 453         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 454 }
 455
 456 /*
 457  * Power actor section: interface to power actors to estimate power
 458  *
 459  * Set of functions used to interact to cooling devices that know
 460  * how to estimate their devices power consumption.
 461  */
 462
 463 /**
 464  * power_actor_get_max_power() - get the maximum power that a cdev can consume
 465  * @cdev:       pointer to &thermal_cooling_device
 466  * @tz:         a valid thermal zone device pointer
 467  * @max_power:  pointer in which to store the maximum power
 468  *
 469  * Calculate the maximum power consumption in milliwats that the
 470  * cooling device can currently consume and store it in @max_power.
 471  *
 472  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 473  * power_actor API or -E* on other error.
 474  */
 475 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
 476                               struct thermal_zone_device *tz, u32 *max_power)
 477 {
 478         if (!cdev_is_power_actor(cdev))
 479                 return -EINVAL;
 480
 481         return cdev->ops->state2power(cdev, tz, 0, max_power);
 482 }
 483
 484 /**
 485  * power_actor_get_min_power() - get the mainimum power that a cdev can consume
 486  * @cdev:       pointer to &thermal_cooling_device
 487  * @tz:         a valid thermal zone device pointer
 488  * @min_power:  pointer in which to store the minimum power
 489  *
 490  * Calculate the minimum power consumption in milliwatts that the
 491  * cooling device can currently consume and store it in @min_power.
 492  *
 493  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 494  * power_actor API or -E* on other error.
 495  */
 496 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
 497                               struct thermal_zone_device *tz, u32 *min_power)
 498 {
 499         unsigned long max_state;
 500         int ret;
 501
 502         if (!cdev_is_power_actor(cdev))
 503                 return -EINVAL;
 504
 505         ret = cdev->ops->get_max_state(cdev, &max_state);
 506         if (ret)
 507                 return ret;
 508
 509         return cdev->ops->state2power(cdev, tz, max_state, min_power);
 510 }
 511
 512 /**
 513  * power_actor_set_power() - limit the maximum power a cooling device consumes
 514  * @cdev:       pointer to &thermal_cooling_device
 515  * @instance:   thermal instance to update
 516  * @power:      the power in milliwatts
 517  *
 518  * Set the cooling device to consume at most @power milliwatts. The limit is
 519  * expected to be a cap at the maximum power consumption.
 520  *
 521  * Return: 0 on success, -EINVAL if the cooling device does not
 522  * implement the power actor API or -E* for other failures.
 523  */
 524 int power_actor_set_power(struct thermal_cooling_device *cdev,
 525                           struct thermal_instance *instance, u32 power)
 526 {
 527         unsigned long state;
 528         int ret;
 529
 530         if (!cdev_is_power_actor(cdev))
 531                 return -EINVAL;
 532
 533         ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
 534         if (ret)
 535                 return ret;
 536
 537         instance->target = state;
 538         mutex_lock(&cdev->lock);
 539         cdev->updated = false;
 540         mutex_unlock(&cdev->lock);
 541         thermal_cdev_update(cdev);
 542
 543         return 0;
 544 }
 545
 546 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
 547                                           const char *cdev_type, size_t size)
 548 {
 549         struct thermal_cooling_device *cdev = NULL;
 550
 551         mutex_lock(&thermal_list_lock);
 552         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 553                 /* skip non matching cdevs */
 554                 if (strncmp(cdev_type, cdev->type, size))
 555                         continue;
 556
 557                 /* re binding the exception matching the type pattern */
 558                 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
 559                                                  THERMAL_NO_LIMIT,
 560                                                  THERMAL_NO_LIMIT,
 561                                                  THERMAL_WEIGHT_DEFAULT);
 562         }
 563         mutex_unlock(&thermal_list_lock);
 564 }
 565
 566 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
 567                                           const char *cdev_type, size_t size)
 568 {
 569         struct thermal_cooling_device *cdev = NULL;
 570
 571         mutex_lock(&thermal_list_lock);
 572         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 573                 /* skip non matching cdevs */
 574                 if (strncmp(cdev_type, cdev->type, size))
 575                         continue;
 576                 /* unbinding the exception matching the type pattern */
 577                 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
 578                                                    cdev);
 579         }
 580         mutex_unlock(&thermal_list_lock);
 581 }
 582
 583 /*
 584  * Device management section: cooling devices, zones devices, and binding
 585  *
 586  * Set of functions provided by the thermal core for:
 587  * - cooling devices lifecycle: registration, unregistration,
 588  *                              binding, and unbinding.
 589  * - thermal zone devices lifecycle: registration, unregistration,
 590  *                                   binding, and unbinding.
 591  */
 592 static int get_idr(struct idr *idr, struct mutex *lock, int *id)
 593 {
 594         int ret;
 595
 596         if (lock)
 597                 mutex_lock(lock);
 598         ret = idr_alloc(idr, NULL, 0, 0, GFP_KERNEL);
 599         if (lock)
 600                 mutex_unlock(lock);
 601         if (unlikely(ret < 0))
 602                 return ret;
 603         *id = ret;
 604         return 0;
 605 }
 606
 607 static void release_idr(struct idr *idr, struct mutex *lock, int id)
 608 {
 609         if (lock)
 610                 mutex_lock(lock);
 611         idr_remove(idr, id);
 612         if (lock)
 613                 mutex_unlock(lock);
 614 }
 615
 616 /**
 617  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 618  * @tz:         pointer to struct thermal_zone_device
 619  * @trip:       indicates which trip point the cooling devices is
 620  *              associated with in this thermal zone.
 621  * @cdev:       pointer to struct thermal_cooling_device
 622  * @upper:      the Maximum cooling state for this trip point.
 623  *              THERMAL_NO_LIMIT means no upper limit,
 624  *              and the cooling device can be in max_state.
 625  * @lower:      the Minimum cooling state can be used for this trip point.
 626  *              THERMAL_NO_LIMIT means no lower limit,
 627  *              and the cooling device can be in cooling state 0.
 628  * @weight:     The weight of the cooling device to be bound to the
 629  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 630  *              default value
 631  *
 632  * This interface function bind a thermal cooling device to the certain trip
 633  * point of a thermal zone device.
 634  * This function is usually called in the thermal zone device .bind callback.
 635  *
 636  * Return: 0 on success, the proper error value otherwise.
 637  */
 638 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 639                                      int trip,
 640                                      struct thermal_cooling_device *cdev,
 641                                      unsigned long upper, unsigned long lower,
 642                                      unsigned int weight)
 643 {
 644         struct thermal_instance *dev;
 645         struct thermal_instance *pos;
 646         struct thermal_zone_device *pos1;
 647         struct thermal_cooling_device *pos2;
 648         unsigned long max_state;
 649         int result, ret;
 650
 651         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 652                 return -EINVAL;
 653
 654         list_for_each_entry(pos1, &thermal_tz_list, node) {
 655                 if (pos1 == tz)
 656                         break;
 657         }
 658         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 659                 if (pos2 == cdev)
 660                         break;
 661         }
 662
 663         if (tz != pos1 || cdev != pos2)
 664                 return -EINVAL;
 665
 666         ret = cdev->ops->get_max_state(cdev, &max_state);
 667         if (ret)
 668                 return ret;
 669
 670         /* lower default 0, upper default max_state */
 671         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 672         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 673
 674         if (lower > upper || upper > max_state)
 675                 return -EINVAL;
 676
 677         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 678         if (!dev)
 679                 return -ENOMEM;
 680         dev->tz = tz;
 681         dev->cdev = cdev;
 682         dev->trip = trip;
 683         dev->upper = upper;
 684         dev->lower = lower;
 685         dev->target = THERMAL_NO_TARGET;
 686         dev->weight = weight;
 687
 688         result = get_idr(&tz->idr, &tz->lock, &dev->id);
 689         if (result)
 690                 goto free_mem;
 691
 692         sprintf(dev->name, "cdev%d", dev->id);
 693         result =
 694             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 695         if (result)
 696                 goto release_idr;
 697
 698         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 699         sysfs_attr_init(&dev->attr.attr);
 700         dev->attr.attr.name = dev->attr_name;
 701         dev->attr.attr.mode = 0444;
 702         dev->attr.show = thermal_cooling_device_trip_point_show;
 703         result = device_create_file(&tz->device, &dev->attr);
 704         if (result)
 705                 goto remove_symbol_link;
 706
 707         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 708         sysfs_attr_init(&dev->weight_attr.attr);
 709         dev->weight_attr.attr.name = dev->weight_attr_name;
 710         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 711         dev->weight_attr.show = thermal_cooling_device_weight_show;
 712         dev->weight_attr.store = thermal_cooling_device_weight_store;
 713         result = device_create_file(&tz->device, &dev->weight_attr);
 714         if (result)
 715                 goto remove_trip_file;
 716
 717         mutex_lock(&tz->lock);
 718         mutex_lock(&cdev->lock);
 719         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 720                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 721                         result = -EEXIST;
 722                         break;
 723                 }
 724         if (!result) {
 725                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 726                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 727                 atomic_set(&tz->need_update, 1);
 728         }
 729         mutex_unlock(&cdev->lock);
 730         mutex_unlock(&tz->lock);
 731
 732         if (!result)
 733                 return 0;
 734
 735         device_remove_file(&tz->device, &dev->weight_attr);
 736 remove_trip_file:
 737         device_remove_file(&tz->device, &dev->attr);
 738 remove_symbol_link:
 739         sysfs_remove_link(&tz->device.kobj, dev->name);
 740 release_idr:
 741         release_idr(&tz->idr, &tz->lock, dev->id);
 742 free_mem:
 743         kfree(dev);
 744         return result;
 745 }
 746 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 747
 748 /**
 749  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 750  *                                        thermal zone.
 751  * @tz:         pointer to a struct thermal_zone_device.
 752  * @trip:       indicates which trip point the cooling devices is
 753  *              associated with in this thermal zone.
 754  * @cdev:       pointer to a struct thermal_cooling_device.
 755  *
 756  * This interface function unbind a thermal cooling device from the certain
 757  * trip point of a thermal zone device.
 758  * This function is usually called in the thermal zone device .unbind callback.
 759  *
 760  * Return: 0 on success, the proper error value otherwise.
 761  */
 762 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 763                                        int trip,
 764                                        struct thermal_cooling_device *cdev)
 765 {
 766         struct thermal_instance *pos, *next;
 767
 768         mutex_lock(&tz->lock);
 769         mutex_lock(&cdev->lock);
 770         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 771                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 772                         list_del(&pos->tz_node);
 773                         list_del(&pos->cdev_node);
 774                         mutex_unlock(&cdev->lock);
 775                         mutex_unlock(&tz->lock);
 776                         goto unbind;
 777                 }
 778         }
 779         mutex_unlock(&cdev->lock);
 780         mutex_unlock(&tz->lock);
 781
 782         return -ENODEV;
 783
 784 unbind:
 785         device_remove_file(&tz->device, &pos->weight_attr);
 786         device_remove_file(&tz->device, &pos->attr);
 787         sysfs_remove_link(&tz->device.kobj, pos->name);
 788         release_idr(&tz->idr, &tz->lock, pos->id);
 789         kfree(pos);
 790         return 0;
 791 }
 792 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 793
 794 static void thermal_release(struct device *dev)
 795 {
 796         struct thermal_zone_device *tz;
 797         struct thermal_cooling_device *cdev;
 798
 799         if (!strncmp(dev_name(dev), "thermal_zone",
 800                      sizeof("thermal_zone") - 1)) {
 801                 tz = to_thermal_zone(dev);
 802                 kfree(tz);
 803         } else if (!strncmp(dev_name(dev), "cooling_device",
 804                             sizeof("cooling_device") - 1)) {
 805                 cdev = to_cooling_device(dev);
 806                 kfree(cdev);
 807         }
 808 }
 809
 810 static struct class thermal_class = {
 811         .name = "thermal",
 812         .dev_release = thermal_release,
 813 };
 814
 815 static inline
 816 void print_bind_err_msg(struct thermal_zone_device *tz,
 817                         struct thermal_cooling_device *cdev, int ret)
 818 {
 819         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 820                 tz->type, cdev->type, ret);
 821 }
 822
 823 static void __bind(struct thermal_zone_device *tz, int mask,
 824                    struct thermal_cooling_device *cdev,
 825                    unsigned long *limits,
 826                    unsigned int weight)
 827 {
 828         int i, ret;
 829
 830         for (i = 0; i < tz->trips; i++) {
 831                 if (mask & (1 << i)) {
 832                         unsigned long upper, lower;
 833
 834                         upper = THERMAL_NO_LIMIT;
 835                         lower = THERMAL_NO_LIMIT;
 836                         if (limits) {
 837                                 lower = limits[i * 2];
 838                                 upper = limits[i * 2 + 1];
 839                         }
 840                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 841                                                                upper, lower,
 842                                                                weight);
 843                         if (ret)
 844                                 print_bind_err_msg(tz, cdev, ret);
 845                 }
 846         }
 847 }
 848
 849 static void bind_cdev(struct thermal_cooling_device *cdev)
 850 {
 851         int i, ret;
 852         const struct thermal_zone_params *tzp;
 853         struct thermal_zone_device *pos = NULL;
 854
 855         mutex_lock(&thermal_list_lock);
 856
 857         list_for_each_entry(pos, &thermal_tz_list, node) {
 858                 if (!pos->tzp && !pos->ops->bind)
 859                         continue;
 860
 861                 if (pos->ops->bind) {
 862                         ret = pos->ops->bind(pos, cdev);
 863                         if (ret)
 864                                 print_bind_err_msg(pos, cdev, ret);
 865                         continue;
 866                 }
 867
 868                 tzp = pos->tzp;
 869                 if (!tzp || !tzp->tbp)
 870                         continue;
 871
 872                 for (i = 0; i < tzp->num_tbps; i++) {
 873                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 874                                 continue;
 875                         if (tzp->tbp[i].match(pos, cdev))
 876                                 continue;
 877                         tzp->tbp[i].cdev = cdev;
 878                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 879                                tzp->tbp[i].binding_limits,
 880                                tzp->tbp[i].weight);
 881                 }
 882         }
 883
 884         mutex_unlock(&thermal_list_lock);
 885 }
 886
 887 /**
 888  * __thermal_cooling_device_register() - register a new thermal cooling device
 889  * @np:         a pointer to a device tree node.
 890  * @type:       the thermal cooling device type.
 891  * @devdata:    device private data.
 892  * @ops:                standard thermal cooling devices callbacks.
 893  *
 894  * This interface function adds a new thermal cooling device (fan/processor/...)
 895  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 896  * to all the thermal zone devices registered at the same time.
 897  * It also gives the opportunity to link the cooling device to a device tree
 898  * node, so that it can be bound to a thermal zone created out of device tree.
 899  *
 900  * Return: a pointer to the created struct thermal_cooling_device or an
 901  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 902  */
 903 static struct thermal_cooling_device *
 904 __thermal_cooling_device_register(struct device_node *np,
 905                                   char *type, void *devdata,
 906                                   const struct thermal_cooling_device_ops *ops)
 907 {
 908         struct thermal_cooling_device *cdev;
 909         struct thermal_zone_device *pos = NULL;
 910         int result;
 911
 912         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
 913                 return ERR_PTR(-EINVAL);
 914
 915         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 916             !ops->set_cur_state)
 917                 return ERR_PTR(-EINVAL);
 918
 919         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 920         if (!cdev)
 921                 return ERR_PTR(-ENOMEM);
 922
 923         result = get_idr(&thermal_cdev_idr, &thermal_idr_lock, &cdev->id);
 924         if (result) {
 925                 kfree(cdev);
 926                 return ERR_PTR(result);
 927         }
 928
 929         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
 930         mutex_init(&cdev->lock);
 931         INIT_LIST_HEAD(&cdev->thermal_instances);
 932         cdev->np = np;
 933         cdev->ops = ops;
 934         cdev->updated = false;
 935         cdev->device.class = &thermal_class;
 936         thermal_cooling_device_setup_sysfs(cdev);
 937         cdev->devdata = devdata;
 938         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 939         result = device_register(&cdev->device);
 940         if (result) {
 941                 release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
 942                 kfree(cdev);
 943                 return ERR_PTR(result);
 944         }
 945
 946         /* Add 'this' new cdev to the global cdev list */
 947         mutex_lock(&thermal_list_lock);
 948         list_add(&cdev->node, &thermal_cdev_list);
 949         mutex_unlock(&thermal_list_lock);
 950
 951         /* Update binding information for 'this' new cdev */
 952         bind_cdev(cdev);
 953
 954         mutex_lock(&thermal_list_lock);
 955         list_for_each_entry(pos, &thermal_tz_list, node)
 956                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
 957                         thermal_zone_device_update(pos,
 958                                                    THERMAL_EVENT_UNSPECIFIED);
 959         mutex_unlock(&thermal_list_lock);
 960
 961         return cdev;
 962 }
 963
 964 /**
 965  * thermal_cooling_device_register() - register a new thermal cooling device
 966  * @type:       the thermal cooling device type.
 967  * @devdata:    device private data.
 968  * @ops:                standard thermal cooling devices callbacks.
 969  *
 970  * This interface function adds a new thermal cooling device (fan/processor/...)
 971  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 972  * to all the thermal zone devices registered at the same time.
 973  *
 974  * Return: a pointer to the created struct thermal_cooling_device or an
 975  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 976  */
 977 struct thermal_cooling_device *
 978 thermal_cooling_device_register(char *type, void *devdata,
 979                                 const struct thermal_cooling_device_ops *ops)
 980 {
 981         return __thermal_cooling_device_register(NULL, type, devdata, ops);
 982 }
 983 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
 984
 985 /**
 986  * thermal_of_cooling_device_register() - register an OF thermal cooling device
 987  * @np:         a pointer to a device tree node.
 988  * @type:       the thermal cooling device type.
 989  * @devdata:    device private data.
 990  * @ops:                standard thermal cooling devices callbacks.
 991  *
 992  * This function will register a cooling device with device tree node reference.
 993  * This interface function adds a new thermal cooling device (fan/processor/...)
 994  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 995  * to all the thermal zone devices registered at the same time.
 996  *
 997  * Return: a pointer to the created struct thermal_cooling_device or an
 998  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 999  */
1000 struct thermal_cooling_device *
1001 thermal_of_cooling_device_register(struct device_node *np,
1002                                    char *type, void *devdata,
1003                                    const struct thermal_cooling_device_ops *ops)
1004 {
1005         return __thermal_cooling_device_register(np, type, devdata, ops);
1006 }
1007 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1008
1009 static void __unbind(struct thermal_zone_device *tz, int mask,
1010                      struct thermal_cooling_device *cdev)
1011 {
1012         int i;
1013
1014         for (i = 0; i < tz->trips; i++)
1015                 if (mask & (1 << i))
1016                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1017 }
1018
1019 /**
1020  * thermal_cooling_device_unregister - removes a thermal cooling device
1021  * @cdev:       the thermal cooling device to remove.
1022  *
1023  * thermal_cooling_device_unregister() must be called when a registered
1024  * thermal cooling device is no longer needed.
1025  */
1026 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1027 {
1028         int i;
1029         const struct thermal_zone_params *tzp;
1030         struct thermal_zone_device *tz;
1031         struct thermal_cooling_device *pos = NULL;
1032
1033         if (!cdev)
1034                 return;
1035
1036         mutex_lock(&thermal_list_lock);
1037         list_for_each_entry(pos, &thermal_cdev_list, node)
1038                 if (pos == cdev)
1039                         break;
1040         if (pos != cdev) {
1041                 /* thermal cooling device not found */
1042                 mutex_unlock(&thermal_list_lock);
1043                 return;
1044         }
1045         list_del(&cdev->node);
1046
1047         /* Unbind all thermal zones associated with 'this' cdev */
1048         list_for_each_entry(tz, &thermal_tz_list, node) {
1049                 if (tz->ops->unbind) {
1050                         tz->ops->unbind(tz, cdev);
1051                         continue;
1052                 }
1053
1054                 if (!tz->tzp || !tz->tzp->tbp)
1055                         continue;
1056
1057                 tzp = tz->tzp;
1058                 for (i = 0; i < tzp->num_tbps; i++) {
1059                         if (tzp->tbp[i].cdev == cdev) {
1060                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1061                                 tzp->tbp[i].cdev = NULL;
1062                         }
1063                 }
1064         }
1065
1066         mutex_unlock(&thermal_list_lock);
1067
1068         release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
1069         device_unregister(&cdev->device);
1070 }
1071 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1072
1073 static void bind_tz(struct thermal_zone_device *tz)
1074 {
1075         int i, ret;
1076         struct thermal_cooling_device *pos = NULL;
1077         const struct thermal_zone_params *tzp = tz->tzp;
1078
1079         if (!tzp && !tz->ops->bind)
1080                 return;
1081
1082         mutex_lock(&thermal_list_lock);
1083
1084         /* If there is ops->bind, try to use ops->bind */
1085         if (tz->ops->bind) {
1086                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1087                         ret = tz->ops->bind(tz, pos);
1088                         if (ret)
1089                                 print_bind_err_msg(tz, pos, ret);
1090                 }
1091                 goto exit;
1092         }
1093
1094         if (!tzp || !tzp->tbp)
1095                 goto exit;
1096
1097         list_for_each_entry(pos, &thermal_cdev_list, node) {
1098                 for (i = 0; i < tzp->num_tbps; i++) {
1099                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1100                                 continue;
1101                         if (tzp->tbp[i].match(tz, pos))
1102                                 continue;
1103                         tzp->tbp[i].cdev = pos;
1104                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1105                                tzp->tbp[i].binding_limits,
1106                                tzp->tbp[i].weight);
1107                 }
1108         }
1109 exit:
1110         mutex_unlock(&thermal_list_lock);
1111 }
1112
1113 /**
1114  * thermal_zone_device_register() - register a new thermal zone device
1115  * @type:       the thermal zone device type
1116  * @trips:      the number of trip points the thermal zone support
1117  * @mask:       a bit string indicating the writeablility of trip points
1118  * @devdata:    private device data
1119  * @ops:        standard thermal zone device callbacks
1120  * @tzp:        thermal zone platform parameters
1121  * @passive_delay: number of milliseconds to wait between polls when
1122  *                 performing passive cooling
1123  * @polling_delay: number of milliseconds to wait between polls when checking
1124  *                 whether trip points have been crossed (0 for interrupt
1125  *                 driven systems)
1126  *
1127  * This interface function adds a new thermal zone device (sensor) to
1128  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1129  * thermal cooling devices registered at the same time.
1130  * thermal_zone_device_unregister() must be called when the device is no
1131  * longer needed. The passive cooling depends on the .get_trend() return value.
1132  *
1133  * Return: a pointer to the created struct thermal_zone_device or an
1134  * in case of error, an ERR_PTR. Caller must check return value with
1135  * IS_ERR*() helpers.
1136  */
1137 struct thermal_zone_device *
1138 thermal_zone_device_register(const char *type, int trips, int mask,
1139                              void *devdata, struct thermal_zone_device_ops *ops,
1140                              struct thermal_zone_params *tzp, int passive_delay,
1141                              int polling_delay)
1142 {
1143         struct thermal_zone_device *tz;
1144         enum thermal_trip_type trip_type;
1145         int trip_temp;
1146         int result;
1147         int count;
1148         struct thermal_governor *governor;
1149
1150         if (!type || strlen(type) == 0)
1151                 return ERR_PTR(-EINVAL);
1152
1153         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1154                 return ERR_PTR(-EINVAL);
1155
1156         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
1157                 return ERR_PTR(-EINVAL);
1158
1159         if (!ops)
1160                 return ERR_PTR(-EINVAL);
1161
1162         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1163                 return ERR_PTR(-EINVAL);
1164
1165         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1166         if (!tz)
1167                 return ERR_PTR(-ENOMEM);
1168
1169         INIT_LIST_HEAD(&tz->thermal_instances);
1170         idr_init(&tz->idr);
1171         mutex_init(&tz->lock);
1172         result = get_idr(&thermal_tz_idr, &thermal_idr_lock, &tz->id);
1173         if (result) {
1174                 kfree(tz);
1175                 return ERR_PTR(result);
1176         }
1177
1178         strlcpy(tz->type, type, sizeof(tz->type));
1179         tz->ops = ops;
1180         tz->tzp = tzp;
1181         tz->device.class = &thermal_class;
1182         tz->devdata = devdata;
1183         tz->trips = trips;
1184         tz->passive_delay = passive_delay;
1185         tz->polling_delay = polling_delay;
1186
1187         /* sys I/F */
1188         /* Add nodes that are always present via .groups */
1189         result = thermal_zone_create_device_groups(tz, mask);
1190         if (result)
1191                 goto unregister;
1192
1193         /* A new thermal zone needs to be updated anyway. */
1194         atomic_set(&tz->need_update, 1);
1195
1196         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1197         result = device_register(&tz->device);
1198         if (result) {
1199                 release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1200                 kfree(tz);
1201                 return ERR_PTR(result);
1202         }
1203
1204         for (count = 0; count < trips; count++) {
1205                 if (tz->ops->get_trip_type(tz, count, &trip_type))
1206                         set_bit(count, &tz->trips_disabled);
1207                 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1208                         set_bit(count, &tz->trips_disabled);
1209                 /* Check for bogus trip points */
1210                 if (trip_temp == 0)
1211                         set_bit(count, &tz->trips_disabled);
1212         }
1213
1214         /* Update 'this' zone's governor information */
1215         mutex_lock(&thermal_governor_lock);
1216
1217         if (tz->tzp)
1218                 governor = __find_governor(tz->tzp->governor_name);
1219         else
1220                 governor = def_governor;
1221
1222         result = thermal_set_governor(tz, governor);
1223         if (result) {
1224                 mutex_unlock(&thermal_governor_lock);
1225                 goto unregister;
1226         }
1227
1228         mutex_unlock(&thermal_governor_lock);
1229
1230         if (!tz->tzp || !tz->tzp->no_hwmon) {
1231                 result = thermal_add_hwmon_sysfs(tz);
1232                 if (result)
1233                         goto unregister;
1234         }
1235
1236         mutex_lock(&thermal_list_lock);
1237         list_add_tail(&tz->node, &thermal_tz_list);
1238         mutex_unlock(&thermal_list_lock);
1239
1240         /* Bind cooling devices for this zone */
1241         bind_tz(tz);
1242
1243         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1244
1245         thermal_zone_device_reset(tz);
1246         /* Update the new thermal zone and mark it as already updated. */
1247         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1248                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1249
1250         return tz;
1251
1252 unregister:
1253         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1254         device_unregister(&tz->device);
1255         return ERR_PTR(result);
1256 }
1257 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1258
1259 /**
1260  * thermal_device_unregister - removes the registered thermal zone device
1261  * @tz: the thermal zone device to remove
1262  */
1263 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1264 {
1265         int i;
1266         const struct thermal_zone_params *tzp;
1267         struct thermal_cooling_device *cdev;
1268         struct thermal_zone_device *pos = NULL;
1269
1270         if (!tz)
1271                 return;
1272
1273         tzp = tz->tzp;
1274
1275         mutex_lock(&thermal_list_lock);
1276         list_for_each_entry(pos, &thermal_tz_list, node)
1277                 if (pos == tz)
1278                         break;
1279         if (pos != tz) {
1280                 /* thermal zone device not found */
1281                 mutex_unlock(&thermal_list_lock);
1282                 return;
1283         }
1284         list_del(&tz->node);
1285
1286         /* Unbind all cdevs associated with 'this' thermal zone */
1287         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1288                 if (tz->ops->unbind) {
1289                         tz->ops->unbind(tz, cdev);
1290                         continue;
1291                 }
1292
1293                 if (!tzp || !tzp->tbp)
1294                         break;
1295
1296                 for (i = 0; i < tzp->num_tbps; i++) {
1297                         if (tzp->tbp[i].cdev == cdev) {
1298                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1299                                 tzp->tbp[i].cdev = NULL;
1300                         }
1301                 }
1302         }
1303
1304         mutex_unlock(&thermal_list_lock);
1305
1306         thermal_zone_device_set_polling(tz, 0);
1307
1308         kfree(tz->trip_type_attrs);
1309         kfree(tz->trip_temp_attrs);
1310         kfree(tz->trip_hyst_attrs);
1311         kfree(tz->trips_attribute_group.attrs);
1312         thermal_set_governor(tz, NULL);
1313
1314         thermal_remove_hwmon_sysfs(tz);
1315         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1316         idr_destroy(&tz->idr);
1317         mutex_destroy(&tz->lock);
1318         device_unregister(&tz->device);
1319         kfree(tz->device.groups);
1320 }
1321 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1322
1323 /**
1324  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1325  * @name: thermal zone name to fetch the temperature
1326  *
1327  * When only one zone is found with the passed name, returns a reference to it.
1328  *
1329  * Return: On success returns a reference to an unique thermal zone with
1330  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1331  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1332  */
1333 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1334 {
1335         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1336         unsigned int found = 0;
1337
1338         if (!name)
1339                 goto exit;
1340
1341         mutex_lock(&thermal_list_lock);
1342         list_for_each_entry(pos, &thermal_tz_list, node)
1343                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1344                         found++;
1345                         ref = pos;
1346                 }
1347         mutex_unlock(&thermal_list_lock);
1348
1349         /* nothing has been found, thus an error code for it */
1350         if (found == 0)
1351                 ref = ERR_PTR(-ENODEV);
1352         else if (found > 1)
1353         /* Success only when an unique zone is found */
1354                 ref = ERR_PTR(-EEXIST);
1355
1356 exit:
1357         return ref;
1358 }
1359 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1360
1361 #ifdef CONFIG_NET
1362 static const struct genl_multicast_group thermal_event_mcgrps[] = {
1363         { .name = THERMAL_GENL_MCAST_GROUP_NAME, },
1364 };
1365
1366 static struct genl_family thermal_event_genl_family __ro_after_init = {
1367         .module = THIS_MODULE,
1368         .name = THERMAL_GENL_FAMILY_NAME,
1369         .version = THERMAL_GENL_VERSION,
1370         .maxattr = THERMAL_GENL_ATTR_MAX,
1371         .mcgrps = thermal_event_mcgrps,
1372         .n_mcgrps = ARRAY_SIZE(thermal_event_mcgrps),
1373 };
1374
1375 int thermal_generate_netlink_event(struct thermal_zone_device *tz,
1376                                    enum events event)
1377 {
1378         struct sk_buff *skb;
1379         struct nlattr *attr;
1380         struct thermal_genl_event *thermal_event;
1381         void *msg_header;
1382         int size;
1383         int result;
1384         static unsigned int thermal_event_seqnum;
1385
1386         if (!tz)
1387                 return -EINVAL;
1388
1389         /* allocate memory */
1390         size = nla_total_size(sizeof(struct thermal_genl_event)) +
1391                nla_total_size(0);
1392
1393         skb = genlmsg_new(size, GFP_ATOMIC);
1394         if (!skb)
1395                 return -ENOMEM;
1396
1397         /* add the genetlink message header */
1398         msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++,
1399                                  &thermal_event_genl_family, 0,
1400                                  THERMAL_GENL_CMD_EVENT);
1401         if (!msg_header) {
1402                 nlmsg_free(skb);
1403                 return -ENOMEM;
1404         }
1405
1406         /* fill the data */
1407         attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT,
1408                            sizeof(struct thermal_genl_event));
1409
1410         if (!attr) {
1411                 nlmsg_free(skb);
1412                 return -EINVAL;
1413         }
1414
1415         thermal_event = nla_data(attr);
1416         if (!thermal_event) {
1417                 nlmsg_free(skb);
1418                 return -EINVAL;
1419         }
1420
1421         memset(thermal_event, 0, sizeof(struct thermal_genl_event));
1422
1423         thermal_event->orig = tz->id;
1424         thermal_event->event = event;
1425
1426         /* send multicast genetlink message */
1427         genlmsg_end(skb, msg_header);
1428
1429         result = genlmsg_multicast(&thermal_event_genl_family, skb, 0,
1430                                    0, GFP_ATOMIC);
1431         if (result)
1432                 dev_err(&tz->device, "Failed to send netlink event:%d", result);
1433
1434         return result;
1435 }
1436 EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
1437
1438 static int __init genetlink_init(void)
1439 {
1440         return genl_register_family(&thermal_event_genl_family);
1441 }
1442
1443 static void genetlink_exit(void)
1444 {
1445         genl_unregister_family(&thermal_event_genl_family);
1446 }
1447 #else /* !CONFIG_NET */
1448 static inline int genetlink_init(void) { return 0; }
1449 static inline void genetlink_exit(void) {}
1450 #endif /* !CONFIG_NET */
1451
1452 static int thermal_pm_notify(struct notifier_block *nb,
1453                              unsigned long mode, void *_unused)
1454 {
1455         struct thermal_zone_device *tz;
1456
1457         switch (mode) {
1458         case PM_HIBERNATION_PREPARE:
1459         case PM_RESTORE_PREPARE:
1460         case PM_SUSPEND_PREPARE:
1461                 atomic_set(&in_suspend, 1);
1462                 break;
1463         case PM_POST_HIBERNATION:
1464         case PM_POST_RESTORE:
1465         case PM_POST_SUSPEND:
1466                 atomic_set(&in_suspend, 0);
1467                 list_for_each_entry(tz, &thermal_tz_list, node) {
1468                         thermal_zone_device_reset(tz);
1469                         thermal_zone_device_update(tz,
1470                                                    THERMAL_EVENT_UNSPECIFIED);
1471                 }
1472                 break;
1473         default:
1474                 break;
1475         }
1476         return 0;
1477 }
1478
1479 static struct notifier_block thermal_pm_nb = {
1480         .notifier_call = thermal_pm_notify,
1481 };
1482
1483 static int __init thermal_init(void)
1484 {
1485         int result;
1486
1487         result = thermal_register_governors();
1488         if (result)
1489                 goto error;
1490
1491         result = class_register(&thermal_class);
1492         if (result)
1493                 goto unregister_governors;
1494
1495         result = genetlink_init();
1496         if (result)
1497                 goto unregister_class;
1498
1499         result = of_parse_thermal_zones();
1500         if (result)
1501                 goto exit_netlink;
1502
1503         result = register_pm_notifier(&thermal_pm_nb);
1504         if (result)
1505                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1506                         result);
1507
1508         return 0;
1509
1510 exit_netlink:
1511         genetlink_exit();
1512 unregister_class:
1513         class_unregister(&thermal_class);
1514 unregister_governors:
1515         thermal_unregister_governors();
1516 error:
1517         idr_destroy(&thermal_tz_idr);
1518         idr_destroy(&thermal_cdev_idr);
1519         mutex_destroy(&thermal_idr_lock);
1520         mutex_destroy(&thermal_list_lock);
1521         mutex_destroy(&thermal_governor_lock);
1522         return result;
1523 }
1524
1525 static void __exit thermal_exit(void)
1526 {
1527         unregister_pm_notifier(&thermal_pm_nb);
1528         of_thermal_destroy_zones();
1529         genetlink_exit();
1530         class_unregister(&thermal_class);
1531         thermal_unregister_governors();
1532         idr_destroy(&thermal_tz_idr);
1533         idr_destroy(&thermal_cdev_idr);
1534         mutex_destroy(&thermal_idr_lock);
1535         mutex_destroy(&thermal_list_lock);
1536         mutex_destroy(&thermal_governor_lock);
1537 }
1538
1539 fs_initcall(thermal_init);
1540 module_exit(thermal_exit);