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 static DEFINE_MUTEX(poweroff_lock);
  40
  41 static atomic_t in_suspend;
  42 static bool power_off_triggered;
  43
  44 static struct thermal_governor *def_governor;
  45
  46 /*
  47  * Governor section: set of functions to handle thermal governors
  48  *
  49  * Functions to help in the life cycle of thermal governors within
  50  * the thermal core and by the thermal governor code.
  51  */
  52
  53 static struct thermal_governor *__find_governor(const char *name)
  54 {
  55         struct thermal_governor *pos;
  56
  57         if (!name || !name[0])
  58                 return def_governor;
  59
  60         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  61                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  62                         return pos;
  63
  64         return NULL;
  65 }
  66
  67 /**
  68  * bind_previous_governor() - bind the previous governor of the thermal zone
  69  * @tz:         a valid pointer to a struct thermal_zone_device
  70  * @failed_gov_name:    the name of the governor that failed to register
  71  *
  72  * Register the previous governor of the thermal zone after a new
  73  * governor has failed to be bound.
  74  */
  75 static void bind_previous_governor(struct thermal_zone_device *tz,
  76                                    const char *failed_gov_name)
  77 {
  78         if (tz->governor && tz->governor->bind_to_tz) {
  79                 if (tz->governor->bind_to_tz(tz)) {
  80                         dev_err(&tz->device,
  81                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  82                                 failed_gov_name, tz->governor->name, tz->type);
  83                         tz->governor = NULL;
  84                 }
  85         }
  86 }
  87
  88 /**
  89  * thermal_set_governor() - Switch to another governor
  90  * @tz:         a valid pointer to a struct thermal_zone_device
  91  * @new_gov:    pointer to the new governor
  92  *
  93  * Change the governor of thermal zone @tz.
  94  *
  95  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
  96  */
  97 static int thermal_set_governor(struct thermal_zone_device *tz,
  98                                 struct thermal_governor *new_gov)
  99 {
 100         int ret = 0;
 101
 102         if (tz->governor && tz->governor->unbind_from_tz)
 103                 tz->governor->unbind_from_tz(tz);
 104
 105         if (new_gov && new_gov->bind_to_tz) {
 106                 ret = new_gov->bind_to_tz(tz);
 107                 if (ret) {
 108                         bind_previous_governor(tz, new_gov->name);
 109
 110                         return ret;
 111                 }
 112         }
 113
 114         tz->governor = new_gov;
 115
 116         return ret;
 117 }
 118
 119 int thermal_register_governor(struct thermal_governor *governor)
 120 {
 121         int err;
 122         const char *name;
 123         struct thermal_zone_device *pos;
 124
 125         if (!governor)
 126                 return -EINVAL;
 127
 128         mutex_lock(&thermal_governor_lock);
 129
 130         err = -EBUSY;
 131         if (!__find_governor(governor->name)) {
 132                 bool match_default;
 133
 134                 err = 0;
 135                 list_add(&governor->governor_list, &thermal_governor_list);
 136                 match_default = !strncmp(governor->name,
 137                                          DEFAULT_THERMAL_GOVERNOR,
 138                                          THERMAL_NAME_LENGTH);
 139
 140                 if (!def_governor && match_default)
 141                         def_governor = governor;
 142         }
 143
 144         mutex_lock(&thermal_list_lock);
 145
 146         list_for_each_entry(pos, &thermal_tz_list, node) {
 147                 /*
 148                  * only thermal zones with specified tz->tzp->governor_name
 149                  * may run with tz->govenor unset
 150                  */
 151                 if (pos->governor)
 152                         continue;
 153
 154                 name = pos->tzp->governor_name;
 155
 156                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 157                         int ret;
 158
 159                         ret = thermal_set_governor(pos, governor);
 160                         if (ret)
 161                                 dev_err(&pos->device,
 162                                         "Failed to set governor %s for thermal zone %s: %d\n",
 163                                         governor->name, pos->type, ret);
 164                 }
 165         }
 166
 167         mutex_unlock(&thermal_list_lock);
 168         mutex_unlock(&thermal_governor_lock);
 169
 170         return err;
 171 }
 172
 173 void thermal_unregister_governor(struct thermal_governor *governor)
 174 {
 175         struct thermal_zone_device *pos;
 176
 177         if (!governor)
 178                 return;
 179
 180         mutex_lock(&thermal_governor_lock);
 181
 182         if (!__find_governor(governor->name))
 183                 goto exit;
 184
 185         mutex_lock(&thermal_list_lock);
 186
 187         list_for_each_entry(pos, &thermal_tz_list, node) {
 188                 if (!strncasecmp(pos->governor->name, governor->name,
 189                                  THERMAL_NAME_LENGTH))
 190                         thermal_set_governor(pos, NULL);
 191         }
 192
 193         mutex_unlock(&thermal_list_lock);
 194         list_del(&governor->governor_list);
 195 exit:
 196         mutex_unlock(&thermal_governor_lock);
 197 }
 198
 199 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 200                                    char *policy)
 201 {
 202         struct thermal_governor *gov;
 203         int ret = -EINVAL;
 204
 205         mutex_lock(&thermal_governor_lock);
 206         mutex_lock(&tz->lock);
 207
 208         gov = __find_governor(strim(policy));
 209         if (!gov)
 210                 goto exit;
 211
 212         ret = thermal_set_governor(tz, gov);
 213
 214 exit:
 215         mutex_unlock(&tz->lock);
 216         mutex_unlock(&thermal_governor_lock);
 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         ssize_t size = PAGE_SIZE;
 226
 227         mutex_lock(&thermal_governor_lock);
 228
 229         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 230                 size = PAGE_SIZE - count;
 231                 count += scnprintf(buf + count, size, "%s ", pos->name);
 232         }
 233         count += scnprintf(buf + count, size, "\n");
 234
 235         mutex_unlock(&thermal_governor_lock);
 236
 237         return count;
 238 }
 239
 240 static void __init thermal_unregister_governors(void)
 241 {
 242         struct thermal_governor **governor;
 243
 244         for_each_governor_table(governor)
 245                 thermal_unregister_governor(*governor);
 246 }
 247
 248 static int __init thermal_register_governors(void)
 249 {
 250         int ret = 0;
 251         struct thermal_governor **governor;
 252
 253         for_each_governor_table(governor) {
 254                 ret = thermal_register_governor(*governor);
 255                 if (ret) {
 256                         pr_err("Failed to register governor: '%s'",
 257                                (*governor)->name);
 258                         break;
 259                 }
 260
 261                 pr_info("Registered thermal governor '%s'",
 262                         (*governor)->name);
 263         }
 264
 265         if (ret) {
 266                 struct thermal_governor **gov;
 267
 268                 for_each_governor_table(gov) {
 269                         if (gov == governor)
 270                                 break;
 271                         thermal_unregister_governor(*gov);
 272                 }
 273         }
 274
 275         return ret;
 276 }
 277
 278 /*
 279  * Zone update section: main control loop applied to each zone while monitoring
 280  *
 281  * in polling mode. The monitoring is done using a workqueue.
 282  * Same update may be done on a zone by calling thermal_zone_device_update().
 283  *
 284  * An update means:
 285  * - Non-critical trips will invoke the governor responsible for that zone;
 286  * - Hot trips will produce a notification to userspace;
 287  * - Critical trip point will cause a system shutdown.
 288  */
 289 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 290                                             int delay)
 291 {
 292         if (delay > 1000)
 293                 mod_delayed_work(system_freezable_power_efficient_wq,
 294                                  &tz->poll_queue,
 295                                  round_jiffies(msecs_to_jiffies(delay)));
 296         else if (delay)
 297                 mod_delayed_work(system_freezable_power_efficient_wq,
 298                                  &tz->poll_queue,
 299                                  msecs_to_jiffies(delay));
 300         else
 301                 cancel_delayed_work(&tz->poll_queue);
 302 }
 303
 304 static inline bool should_stop_polling(struct thermal_zone_device *tz)
 305 {
 306         return !thermal_zone_device_is_enabled(tz);
 307 }
 308
 309 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 310 {
 311         bool stop;
 312
 313         stop = should_stop_polling(tz);
 314
 315         mutex_lock(&tz->lock);
 316
 317         if (!stop && tz->passive)
 318                 thermal_zone_device_set_polling(tz, tz->passive_delay);
 319         else if (!stop && tz->polling_delay)
 320                 thermal_zone_device_set_polling(tz, tz->polling_delay);
 321         else
 322                 thermal_zone_device_set_polling(tz, 0);
 323
 324         mutex_unlock(&tz->lock);
 325 }
 326
 327 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
 328 {
 329         tz->governor ? tz->governor->throttle(tz, trip) :
 330                        def_governor->throttle(tz, trip);
 331 }
 332
 333 /**
 334  * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
 335  * @work: work_struct associated with the emergency poweroff function
 336  *
 337  * This function is called in very critical situations to force
 338  * a kernel poweroff after a configurable timeout value.
 339  */
 340 static void thermal_emergency_poweroff_func(struct work_struct *work)
 341 {
 342         /*
 343          * We have reached here after the emergency thermal shutdown
 344          * Waiting period has expired. This means orderly_poweroff has
 345          * not been able to shut off the system for some reason.
 346          * Try to shut down the system immediately using kernel_power_off
 347          * if populated
 348          */
 349         WARN(1, "Attempting kernel_power_off: Temperature too high\n");
 350         kernel_power_off();
 351
 352         /*
 353          * Worst of the worst case trigger emergency restart
 354          */
 355         WARN(1, "Attempting emergency_restart: Temperature too high\n");
 356         emergency_restart();
 357 }
 358
 359 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
 360                             thermal_emergency_poweroff_func);
 361
 362 /**
 363  * thermal_emergency_poweroff - Trigger an emergency system poweroff
 364  *
 365  * This may be called from any critical situation to trigger a system shutdown
 366  * after a known period of time. By default this is not scheduled.
 367  */
 368 static void thermal_emergency_poweroff(void)
 369 {
 370         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 371         /*
 372          * poweroff_delay_ms must be a carefully profiled positive value.
 373          * Its a must for thermal_emergency_poweroff_work to be scheduled
 374          */
 375         if (poweroff_delay_ms <= 0)
 376                 return;
 377         schedule_delayed_work(&thermal_emergency_poweroff_work,
 378                               msecs_to_jiffies(poweroff_delay_ms));
 379 }
 380
 381 static void handle_critical_trips(struct thermal_zone_device *tz,
 382                                   int trip, enum thermal_trip_type trip_type)
 383 {
 384         int trip_temp;
 385
 386         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 387
 388         /* If we have not crossed the trip_temp, we do not care. */
 389         if (trip_temp <= 0 || tz->temperature < trip_temp)
 390                 return;
 391
 392         trace_thermal_zone_trip(tz, trip, trip_type);
 393
 394         if (tz->ops->notify)
 395                 tz->ops->notify(tz, trip, trip_type);
 396
 397         if (trip_type == THERMAL_TRIP_CRITICAL) {
 398                 dev_emerg(&tz->device,
 399                           "critical temperature reached (%d C), shutting down\n",
 400                           tz->temperature / 1000);
 401                 mutex_lock(&poweroff_lock);
 402                 if (!power_off_triggered) {
 403                         /*
 404                          * Queue a backup emergency shutdown in the event of
 405                          * orderly_poweroff failure
 406                          */
 407                         thermal_emergency_poweroff();
 408                         orderly_poweroff(true);
 409                         power_off_triggered = true;
 410                 }
 411                 mutex_unlock(&poweroff_lock);
 412         }
 413 }
 414
 415 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 416 {
 417         enum thermal_trip_type type;
 418
 419         /* Ignore disabled trip points */
 420         if (test_bit(trip, &tz->trips_disabled))
 421                 return;
 422
 423         tz->ops->get_trip_type(tz, trip, &type);
 424
 425         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 426                 handle_critical_trips(tz, trip, type);
 427         else
 428                 handle_non_critical_trips(tz, trip);
 429         /*
 430          * Alright, we handled this trip successfully.
 431          * So, start monitoring again.
 432          */
 433         monitor_thermal_zone(tz);
 434 }
 435
 436 static void update_temperature(struct thermal_zone_device *tz)
 437 {
 438         int temp, ret;
 439
 440         ret = thermal_zone_get_temp(tz, &temp);
 441         if (ret) {
 442                 if (ret != -EAGAIN)
 443                         dev_warn(&tz->device,
 444                                  "failed to read out thermal zone (%d)\n",
 445                                  ret);
 446                 return;
 447         }
 448
 449         mutex_lock(&tz->lock);
 450         tz->last_temperature = tz->temperature;
 451         tz->temperature = temp;
 452         mutex_unlock(&tz->lock);
 453
 454         trace_thermal_temperature(tz);
 455 }
 456
 457 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 458 {
 459         struct thermal_instance *pos;
 460         tz->temperature = THERMAL_TEMP_INVALID;
 461         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 462                 pos->initialized = false;
 463 }
 464
 465 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 466 {
 467         tz->passive = 0;
 468         thermal_zone_device_init(tz);
 469 }
 470
 471 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
 472                                         enum thermal_device_mode mode)
 473 {
 474         int ret = 0;
 475
 476         mutex_lock(&tz->lock);
 477
 478         /* do nothing if mode isn't changing */
 479         if (mode == tz->mode) {
 480                 mutex_unlock(&tz->lock);
 481
 482                 return ret;
 483         }
 484
 485         if (tz->ops->set_mode)
 486                 ret = tz->ops->set_mode(tz, mode);
 487
 488         if (!ret)
 489                 tz->mode = mode;
 490
 491         mutex_unlock(&tz->lock);
 492
 493         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 494
 495         return ret;
 496 }
 497
 498 int thermal_zone_device_enable(struct thermal_zone_device *tz)
 499 {
 500         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
 501 }
 502 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
 503
 504 int thermal_zone_device_disable(struct thermal_zone_device *tz)
 505 {
 506         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
 507 }
 508 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
 509
 510 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
 511 {
 512         enum thermal_device_mode mode;
 513
 514         mutex_lock(&tz->lock);
 515
 516         mode = tz->mode;
 517
 518         mutex_unlock(&tz->lock);
 519
 520         return mode == THERMAL_DEVICE_ENABLED;
 521 }
 522 EXPORT_SYMBOL_GPL(thermal_zone_device_is_enabled);
 523
 524 void thermal_zone_device_update(struct thermal_zone_device *tz,
 525                                 enum thermal_notify_event event)
 526 {
 527         int count;
 528
 529         if (should_stop_polling(tz))
 530                 return;
 531
 532         if (atomic_read(&in_suspend))
 533                 return;
 534
 535         if (!tz->ops->get_temp)
 536                 return;
 537
 538         update_temperature(tz);
 539
 540         thermal_zone_set_trips(tz);
 541
 542         tz->notify_event = event;
 543
 544         for (count = 0; count < tz->trips; count++)
 545                 handle_thermal_trip(tz, count);
 546 }
 547 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 548
 549 /**
 550  * thermal_notify_framework - Sensor drivers use this API to notify framework
 551  * @tz:         thermal zone device
 552  * @trip:       indicates which trip point has been crossed
 553  *
 554  * This function handles the trip events from sensor drivers. It starts
 555  * throttling the cooling devices according to the policy configured.
 556  * For CRITICAL and HOT trip points, this notifies the respective drivers,
 557  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
 558  * The throttling policy is based on the configured platform data; if no
 559  * platform data is provided, this uses the step_wise throttling policy.
 560  */
 561 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
 562 {
 563         handle_thermal_trip(tz, trip);
 564 }
 565 EXPORT_SYMBOL_GPL(thermal_notify_framework);
 566
 567 static void thermal_zone_device_check(struct work_struct *work)
 568 {
 569         struct thermal_zone_device *tz = container_of(work, struct
 570                                                       thermal_zone_device,
 571                                                       poll_queue.work);
 572         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 573 }
 574
 575 /*
 576  * Power actor section: interface to power actors to estimate power
 577  *
 578  * Set of functions used to interact to cooling devices that know
 579  * how to estimate their devices power consumption.
 580  */
 581
 582 /**
 583  * power_actor_get_max_power() - get the maximum power that a cdev can consume
 584  * @cdev:       pointer to &thermal_cooling_device
 585  * @tz:         a valid thermal zone device pointer
 586  * @max_power:  pointer in which to store the maximum power
 587  *
 588  * Calculate the maximum power consumption in milliwats that the
 589  * cooling device can currently consume and store it in @max_power.
 590  *
 591  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 592  * power_actor API or -E* on other error.
 593  */
 594 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
 595                               struct thermal_zone_device *tz, u32 *max_power)
 596 {
 597         if (!cdev_is_power_actor(cdev))
 598                 return -EINVAL;
 599
 600         return cdev->ops->state2power(cdev, tz, 0, max_power);
 601 }
 602
 603 /**
 604  * power_actor_get_min_power() - get the mainimum power that a cdev can consume
 605  * @cdev:       pointer to &thermal_cooling_device
 606  * @tz:         a valid thermal zone device pointer
 607  * @min_power:  pointer in which to store the minimum power
 608  *
 609  * Calculate the minimum power consumption in milliwatts that the
 610  * cooling device can currently consume and store it in @min_power.
 611  *
 612  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 613  * power_actor API or -E* on other error.
 614  */
 615 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
 616                               struct thermal_zone_device *tz, u32 *min_power)
 617 {
 618         unsigned long max_state;
 619         int ret;
 620
 621         if (!cdev_is_power_actor(cdev))
 622                 return -EINVAL;
 623
 624         ret = cdev->ops->get_max_state(cdev, &max_state);
 625         if (ret)
 626                 return ret;
 627
 628         return cdev->ops->state2power(cdev, tz, max_state, min_power);
 629 }
 630
 631 /**
 632  * power_actor_set_power() - limit the maximum power a cooling device consumes
 633  * @cdev:       pointer to &thermal_cooling_device
 634  * @instance:   thermal instance to update
 635  * @power:      the power in milliwatts
 636  *
 637  * Set the cooling device to consume at most @power milliwatts. The limit is
 638  * expected to be a cap at the maximum power consumption.
 639  *
 640  * Return: 0 on success, -EINVAL if the cooling device does not
 641  * implement the power actor API or -E* for other failures.
 642  */
 643 int power_actor_set_power(struct thermal_cooling_device *cdev,
 644                           struct thermal_instance *instance, u32 power)
 645 {
 646         unsigned long state;
 647         int ret;
 648
 649         if (!cdev_is_power_actor(cdev))
 650                 return -EINVAL;
 651
 652         ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
 653         if (ret)
 654                 return ret;
 655
 656         instance->target = state;
 657         mutex_lock(&cdev->lock);
 658         cdev->updated = false;
 659         mutex_unlock(&cdev->lock);
 660         thermal_cdev_update(cdev);
 661
 662         return 0;
 663 }
 664
 665 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
 666                                           const char *cdev_type, size_t size)
 667 {
 668         struct thermal_cooling_device *cdev = NULL;
 669
 670         mutex_lock(&thermal_list_lock);
 671         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 672                 /* skip non matching cdevs */
 673                 if (strncmp(cdev_type, cdev->type, size))
 674                         continue;
 675
 676                 /* re binding the exception matching the type pattern */
 677                 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
 678                                                  THERMAL_NO_LIMIT,
 679                                                  THERMAL_NO_LIMIT,
 680                                                  THERMAL_WEIGHT_DEFAULT);
 681         }
 682         mutex_unlock(&thermal_list_lock);
 683 }
 684
 685 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
 686                                           const char *cdev_type, size_t size)
 687 {
 688         struct thermal_cooling_device *cdev = NULL;
 689
 690         mutex_lock(&thermal_list_lock);
 691         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 692                 /* skip non matching cdevs */
 693                 if (strncmp(cdev_type, cdev->type, size))
 694                         continue;
 695                 /* unbinding the exception matching the type pattern */
 696                 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
 697                                                    cdev);
 698         }
 699         mutex_unlock(&thermal_list_lock);
 700 }
 701
 702 /*
 703  * Device management section: cooling devices, zones devices, and binding
 704  *
 705  * Set of functions provided by the thermal core for:
 706  * - cooling devices lifecycle: registration, unregistration,
 707  *                              binding, and unbinding.
 708  * - thermal zone devices lifecycle: registration, unregistration,
 709  *                                   binding, and unbinding.
 710  */
 711
 712 /**
 713  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 714  * @tz:         pointer to struct thermal_zone_device
 715  * @trip:       indicates which trip point the cooling devices is
 716  *              associated with in this thermal zone.
 717  * @cdev:       pointer to struct thermal_cooling_device
 718  * @upper:      the Maximum cooling state for this trip point.
 719  *              THERMAL_NO_LIMIT means no upper limit,
 720  *              and the cooling device can be in max_state.
 721  * @lower:      the Minimum cooling state can be used for this trip point.
 722  *              THERMAL_NO_LIMIT means no lower limit,
 723  *              and the cooling device can be in cooling state 0.
 724  * @weight:     The weight of the cooling device to be bound to the
 725  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 726  *              default value
 727  *
 728  * This interface function bind a thermal cooling device to the certain trip
 729  * point of a thermal zone device.
 730  * This function is usually called in the thermal zone device .bind callback.
 731  *
 732  * Return: 0 on success, the proper error value otherwise.
 733  */
 734 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 735                                      int trip,
 736                                      struct thermal_cooling_device *cdev,
 737                                      unsigned long upper, unsigned long lower,
 738                                      unsigned int weight)
 739 {
 740         struct thermal_instance *dev;
 741         struct thermal_instance *pos;
 742         struct thermal_zone_device *pos1;
 743         struct thermal_cooling_device *pos2;
 744         unsigned long max_state;
 745         int result, ret;
 746
 747         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 748                 return -EINVAL;
 749
 750         list_for_each_entry(pos1, &thermal_tz_list, node) {
 751                 if (pos1 == tz)
 752                         break;
 753         }
 754         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 755                 if (pos2 == cdev)
 756                         break;
 757         }
 758
 759         if (tz != pos1 || cdev != pos2)
 760                 return -EINVAL;
 761
 762         ret = cdev->ops->get_max_state(cdev, &max_state);
 763         if (ret)
 764                 return ret;
 765
 766         /* lower default 0, upper default max_state */
 767         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 768         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 769
 770         if (lower > upper || upper > max_state)
 771                 return -EINVAL;
 772
 773         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 774         if (!dev)
 775                 return -ENOMEM;
 776         dev->tz = tz;
 777         dev->cdev = cdev;
 778         dev->trip = trip;
 779         dev->upper = upper;
 780         dev->lower = lower;
 781         dev->target = THERMAL_NO_TARGET;
 782         dev->weight = weight;
 783
 784         result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
 785         if (result < 0)
 786                 goto free_mem;
 787
 788         dev->id = result;
 789         sprintf(dev->name, "cdev%d", dev->id);
 790         result =
 791             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 792         if (result)
 793                 goto release_ida;
 794
 795         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 796         sysfs_attr_init(&dev->attr.attr);
 797         dev->attr.attr.name = dev->attr_name;
 798         dev->attr.attr.mode = 0444;
 799         dev->attr.show = trip_point_show;
 800         result = device_create_file(&tz->device, &dev->attr);
 801         if (result)
 802                 goto remove_symbol_link;
 803
 804         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 805         sysfs_attr_init(&dev->weight_attr.attr);
 806         dev->weight_attr.attr.name = dev->weight_attr_name;
 807         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 808         dev->weight_attr.show = weight_show;
 809         dev->weight_attr.store = weight_store;
 810         result = device_create_file(&tz->device, &dev->weight_attr);
 811         if (result)
 812                 goto remove_trip_file;
 813
 814         mutex_lock(&tz->lock);
 815         mutex_lock(&cdev->lock);
 816         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 817                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 818                         result = -EEXIST;
 819                         break;
 820                 }
 821         if (!result) {
 822                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 823                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 824                 atomic_set(&tz->need_update, 1);
 825         }
 826         mutex_unlock(&cdev->lock);
 827         mutex_unlock(&tz->lock);
 828
 829         if (!result)
 830                 return 0;
 831
 832         device_remove_file(&tz->device, &dev->weight_attr);
 833 remove_trip_file:
 834         device_remove_file(&tz->device, &dev->attr);
 835 remove_symbol_link:
 836         sysfs_remove_link(&tz->device.kobj, dev->name);
 837 release_ida:
 838         ida_simple_remove(&tz->ida, dev->id);
 839 free_mem:
 840         kfree(dev);
 841         return result;
 842 }
 843 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 844
 845 /**
 846  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 847  *                                        thermal zone.
 848  * @tz:         pointer to a struct thermal_zone_device.
 849  * @trip:       indicates which trip point the cooling devices is
 850  *              associated with in this thermal zone.
 851  * @cdev:       pointer to a struct thermal_cooling_device.
 852  *
 853  * This interface function unbind a thermal cooling device from the certain
 854  * trip point of a thermal zone device.
 855  * This function is usually called in the thermal zone device .unbind callback.
 856  *
 857  * Return: 0 on success, the proper error value otherwise.
 858  */
 859 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 860                                        int trip,
 861                                        struct thermal_cooling_device *cdev)
 862 {
 863         struct thermal_instance *pos, *next;
 864
 865         mutex_lock(&tz->lock);
 866         mutex_lock(&cdev->lock);
 867         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 868                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 869                         list_del(&pos->tz_node);
 870                         list_del(&pos->cdev_node);
 871                         mutex_unlock(&cdev->lock);
 872                         mutex_unlock(&tz->lock);
 873                         goto unbind;
 874                 }
 875         }
 876         mutex_unlock(&cdev->lock);
 877         mutex_unlock(&tz->lock);
 878
 879         return -ENODEV;
 880
 881 unbind:
 882         device_remove_file(&tz->device, &pos->weight_attr);
 883         device_remove_file(&tz->device, &pos->attr);
 884         sysfs_remove_link(&tz->device.kobj, pos->name);
 885         ida_simple_remove(&tz->ida, pos->id);
 886         kfree(pos);
 887         return 0;
 888 }
 889 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 890
 891 static void thermal_release(struct device *dev)
 892 {
 893         struct thermal_zone_device *tz;
 894         struct thermal_cooling_device *cdev;
 895
 896         if (!strncmp(dev_name(dev), "thermal_zone",
 897                      sizeof("thermal_zone") - 1)) {
 898                 tz = to_thermal_zone(dev);
 899                 thermal_zone_destroy_device_groups(tz);
 900                 kfree(tz);
 901         } else if (!strncmp(dev_name(dev), "cooling_device",
 902                             sizeof("cooling_device") - 1)) {
 903                 cdev = to_cooling_device(dev);
 904                 kfree(cdev);
 905         }
 906 }
 907
 908 static struct class thermal_class = {
 909         .name = "thermal",
 910         .dev_release = thermal_release,
 911 };
 912
 913 static inline
 914 void print_bind_err_msg(struct thermal_zone_device *tz,
 915                         struct thermal_cooling_device *cdev, int ret)
 916 {
 917         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 918                 tz->type, cdev->type, ret);
 919 }
 920
 921 static void __bind(struct thermal_zone_device *tz, int mask,
 922                    struct thermal_cooling_device *cdev,
 923                    unsigned long *limits,
 924                    unsigned int weight)
 925 {
 926         int i, ret;
 927
 928         for (i = 0; i < tz->trips; i++) {
 929                 if (mask & (1 << i)) {
 930                         unsigned long upper, lower;
 931
 932                         upper = THERMAL_NO_LIMIT;
 933                         lower = THERMAL_NO_LIMIT;
 934                         if (limits) {
 935                                 lower = limits[i * 2];
 936                                 upper = limits[i * 2 + 1];
 937                         }
 938                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 939                                                                upper, lower,
 940                                                                weight);
 941                         if (ret)
 942                                 print_bind_err_msg(tz, cdev, ret);
 943                 }
 944         }
 945 }
 946
 947 static void bind_cdev(struct thermal_cooling_device *cdev)
 948 {
 949         int i, ret;
 950         const struct thermal_zone_params *tzp;
 951         struct thermal_zone_device *pos = NULL;
 952
 953         mutex_lock(&thermal_list_lock);
 954
 955         list_for_each_entry(pos, &thermal_tz_list, node) {
 956                 if (!pos->tzp && !pos->ops->bind)
 957                         continue;
 958
 959                 if (pos->ops->bind) {
 960                         ret = pos->ops->bind(pos, cdev);
 961                         if (ret)
 962                                 print_bind_err_msg(pos, cdev, ret);
 963                         continue;
 964                 }
 965
 966                 tzp = pos->tzp;
 967                 if (!tzp || !tzp->tbp)
 968                         continue;
 969
 970                 for (i = 0; i < tzp->num_tbps; i++) {
 971                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 972                                 continue;
 973                         if (tzp->tbp[i].match(pos, cdev))
 974                                 continue;
 975                         tzp->tbp[i].cdev = cdev;
 976                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 977                                tzp->tbp[i].binding_limits,
 978                                tzp->tbp[i].weight);
 979                 }
 980         }
 981
 982         mutex_unlock(&thermal_list_lock);
 983 }
 984
 985 /**
 986  * __thermal_cooling_device_register() - register a new 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 interface function adds a new thermal cooling device (fan/processor/...)
 993  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 994  * to all the thermal zone devices registered at the same time.
 995  * It also gives the opportunity to link the cooling device to a device tree
 996  * node, so that it can be bound to a thermal zone created out of device tree.
 997  *
 998  * Return: a pointer to the created struct thermal_cooling_device or an
 999  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1000  */
1001 static struct thermal_cooling_device *
1002 __thermal_cooling_device_register(struct device_node *np,
1003                                   const char *type, void *devdata,
1004                                   const struct thermal_cooling_device_ops *ops)
1005 {
1006         struct thermal_cooling_device *cdev;
1007         struct thermal_zone_device *pos = NULL;
1008         int result;
1009
1010         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1011                 return ERR_PTR(-EINVAL);
1012
1013         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1014             !ops->set_cur_state)
1015                 return ERR_PTR(-EINVAL);
1016
1017         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
1018         if (!cdev)
1019                 return ERR_PTR(-ENOMEM);
1020
1021         result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
1022         if (result < 0) {
1023                 kfree(cdev);
1024                 return ERR_PTR(result);
1025         }
1026
1027         cdev->id = result;
1028         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
1029         mutex_init(&cdev->lock);
1030         INIT_LIST_HEAD(&cdev->thermal_instances);
1031         cdev->np = np;
1032         cdev->ops = ops;
1033         cdev->updated = false;
1034         cdev->device.class = &thermal_class;
1035         cdev->devdata = devdata;
1036         thermal_cooling_device_setup_sysfs(cdev);
1037         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1038         result = device_register(&cdev->device);
1039         if (result) {
1040                 ida_simple_remove(&thermal_cdev_ida, cdev->id);
1041                 put_device(&cdev->device);
1042                 return ERR_PTR(result);
1043         }
1044
1045         /* Add 'this' new cdev to the global cdev list */
1046         mutex_lock(&thermal_list_lock);
1047         list_add(&cdev->node, &thermal_cdev_list);
1048         mutex_unlock(&thermal_list_lock);
1049
1050         /* Update binding information for 'this' new cdev */
1051         bind_cdev(cdev);
1052
1053         mutex_lock(&thermal_list_lock);
1054         list_for_each_entry(pos, &thermal_tz_list, node)
1055                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1056                         thermal_zone_device_update(pos,
1057                                                    THERMAL_EVENT_UNSPECIFIED);
1058         mutex_unlock(&thermal_list_lock);
1059
1060         return cdev;
1061 }
1062
1063 /**
1064  * thermal_cooling_device_register() - register a new thermal cooling device
1065  * @type:       the thermal cooling device type.
1066  * @devdata:    device private data.
1067  * @ops:                standard thermal cooling devices callbacks.
1068  *
1069  * This interface function adds a new thermal cooling device (fan/processor/...)
1070  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1071  * to all the thermal zone devices registered at the same time.
1072  *
1073  * Return: a pointer to the created struct thermal_cooling_device or an
1074  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1075  */
1076 struct thermal_cooling_device *
1077 thermal_cooling_device_register(const char *type, void *devdata,
1078                                 const struct thermal_cooling_device_ops *ops)
1079 {
1080         return __thermal_cooling_device_register(NULL, type, devdata, ops);
1081 }
1082 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1083
1084 /**
1085  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1086  * @np:         a pointer to a device tree node.
1087  * @type:       the thermal cooling device type.
1088  * @devdata:    device private data.
1089  * @ops:                standard thermal cooling devices callbacks.
1090  *
1091  * This function will register a cooling device with device tree node reference.
1092  * This interface function adds a new thermal cooling device (fan/processor/...)
1093  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1094  * to all the thermal zone devices registered at the same time.
1095  *
1096  * Return: a pointer to the created struct thermal_cooling_device or an
1097  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1098  */
1099 struct thermal_cooling_device *
1100 thermal_of_cooling_device_register(struct device_node *np,
1101                                    const char *type, void *devdata,
1102                                    const struct thermal_cooling_device_ops *ops)
1103 {
1104         return __thermal_cooling_device_register(np, type, devdata, ops);
1105 }
1106 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1107
1108 static void thermal_cooling_device_release(struct device *dev, void *res)
1109 {
1110         thermal_cooling_device_unregister(
1111                                 *(struct thermal_cooling_device **)res);
1112 }
1113
1114 /**
1115  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1116  *                                             device
1117  * @dev:        a valid struct device pointer of a sensor device.
1118  * @np:         a pointer to a device tree node.
1119  * @type:       the thermal cooling device type.
1120  * @devdata:    device private data.
1121  * @ops:        standard thermal cooling devices callbacks.
1122  *
1123  * This function will register a cooling device with device tree node reference.
1124  * This interface function adds a new thermal cooling device (fan/processor/...)
1125  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1126  * to all the thermal zone devices registered at the same time.
1127  *
1128  * Return: a pointer to the created struct thermal_cooling_device or an
1129  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1130  */
1131 struct thermal_cooling_device *
1132 devm_thermal_of_cooling_device_register(struct device *dev,
1133                                 struct device_node *np,
1134                                 char *type, void *devdata,
1135                                 const struct thermal_cooling_device_ops *ops)
1136 {
1137         struct thermal_cooling_device **ptr, *tcd;
1138
1139         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1140                            GFP_KERNEL);
1141         if (!ptr)
1142                 return ERR_PTR(-ENOMEM);
1143
1144         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1145         if (IS_ERR(tcd)) {
1146                 devres_free(ptr);
1147                 return tcd;
1148         }
1149
1150         *ptr = tcd;
1151         devres_add(dev, ptr);
1152
1153         return tcd;
1154 }
1155 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1156
1157 static void __unbind(struct thermal_zone_device *tz, int mask,
1158                      struct thermal_cooling_device *cdev)
1159 {
1160         int i;
1161
1162         for (i = 0; i < tz->trips; i++)
1163                 if (mask & (1 << i))
1164                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1165 }
1166
1167 /**
1168  * thermal_cooling_device_unregister - removes a thermal cooling device
1169  * @cdev:       the thermal cooling device to remove.
1170  *
1171  * thermal_cooling_device_unregister() must be called when a registered
1172  * thermal cooling device is no longer needed.
1173  */
1174 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1175 {
1176         int i;
1177         const struct thermal_zone_params *tzp;
1178         struct thermal_zone_device *tz;
1179         struct thermal_cooling_device *pos = NULL;
1180
1181         if (!cdev)
1182                 return;
1183
1184         mutex_lock(&thermal_list_lock);
1185         list_for_each_entry(pos, &thermal_cdev_list, node)
1186                 if (pos == cdev)
1187                         break;
1188         if (pos != cdev) {
1189                 /* thermal cooling device not found */
1190                 mutex_unlock(&thermal_list_lock);
1191                 return;
1192         }
1193         list_del(&cdev->node);
1194
1195         /* Unbind all thermal zones associated with 'this' cdev */
1196         list_for_each_entry(tz, &thermal_tz_list, node) {
1197                 if (tz->ops->unbind) {
1198                         tz->ops->unbind(tz, cdev);
1199                         continue;
1200                 }
1201
1202                 if (!tz->tzp || !tz->tzp->tbp)
1203                         continue;
1204
1205                 tzp = tz->tzp;
1206                 for (i = 0; i < tzp->num_tbps; i++) {
1207                         if (tzp->tbp[i].cdev == cdev) {
1208                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1209                                 tzp->tbp[i].cdev = NULL;
1210                         }
1211                 }
1212         }
1213
1214         mutex_unlock(&thermal_list_lock);
1215
1216         ida_simple_remove(&thermal_cdev_ida, cdev->id);
1217         device_del(&cdev->device);
1218         thermal_cooling_device_destroy_sysfs(cdev);
1219         put_device(&cdev->device);
1220 }
1221 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1222
1223 static void bind_tz(struct thermal_zone_device *tz)
1224 {
1225         int i, ret;
1226         struct thermal_cooling_device *pos = NULL;
1227         const struct thermal_zone_params *tzp = tz->tzp;
1228
1229         if (!tzp && !tz->ops->bind)
1230                 return;
1231
1232         mutex_lock(&thermal_list_lock);
1233
1234         /* If there is ops->bind, try to use ops->bind */
1235         if (tz->ops->bind) {
1236                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1237                         ret = tz->ops->bind(tz, pos);
1238                         if (ret)
1239                                 print_bind_err_msg(tz, pos, ret);
1240                 }
1241                 goto exit;
1242         }
1243
1244         if (!tzp || !tzp->tbp)
1245                 goto exit;
1246
1247         list_for_each_entry(pos, &thermal_cdev_list, node) {
1248                 for (i = 0; i < tzp->num_tbps; i++) {
1249                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1250                                 continue;
1251                         if (tzp->tbp[i].match(tz, pos))
1252                                 continue;
1253                         tzp->tbp[i].cdev = pos;
1254                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1255                                tzp->tbp[i].binding_limits,
1256                                tzp->tbp[i].weight);
1257                 }
1258         }
1259 exit:
1260         mutex_unlock(&thermal_list_lock);
1261 }
1262
1263 /**
1264  * thermal_zone_device_register() - register a new thermal zone device
1265  * @type:       the thermal zone device type
1266  * @trips:      the number of trip points the thermal zone support
1267  * @mask:       a bit string indicating the writeablility of trip points
1268  * @devdata:    private device data
1269  * @ops:        standard thermal zone device callbacks
1270  * @tzp:        thermal zone platform parameters
1271  * @passive_delay: number of milliseconds to wait between polls when
1272  *                 performing passive cooling
1273  * @polling_delay: number of milliseconds to wait between polls when checking
1274  *                 whether trip points have been crossed (0 for interrupt
1275  *                 driven systems)
1276  *
1277  * This interface function adds a new thermal zone device (sensor) to
1278  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1279  * thermal cooling devices registered at the same time.
1280  * thermal_zone_device_unregister() must be called when the device is no
1281  * longer needed. The passive cooling depends on the .get_trend() return value.
1282  *
1283  * Return: a pointer to the created struct thermal_zone_device or an
1284  * in case of error, an ERR_PTR. Caller must check return value with
1285  * IS_ERR*() helpers.
1286  */
1287 struct thermal_zone_device *
1288 thermal_zone_device_register(const char *type, int trips, int mask,
1289                              void *devdata, struct thermal_zone_device_ops *ops,
1290                              struct thermal_zone_params *tzp, int passive_delay,
1291                              int polling_delay)
1292 {
1293         struct thermal_zone_device *tz;
1294         enum thermal_trip_type trip_type;
1295         int trip_temp;
1296         int id;
1297         int result;
1298         int count;
1299         struct thermal_governor *governor;
1300
1301         if (!type || strlen(type) == 0) {
1302                 pr_err("Error: No thermal zone type defined\n");
1303                 return ERR_PTR(-EINVAL);
1304         }
1305
1306         if (type && strlen(type) >= THERMAL_NAME_LENGTH) {
1307                 pr_err("Error: Thermal zone name (%s) too long, should be under %d chars\n",
1308                        type, THERMAL_NAME_LENGTH);
1309                 return ERR_PTR(-EINVAL);
1310         }
1311
1312         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) {
1313                 pr_err("Error: Incorrect number of thermal trips\n");
1314                 return ERR_PTR(-EINVAL);
1315         }
1316
1317         if (!ops) {
1318                 pr_err("Error: Thermal zone device ops not defined\n");
1319                 return ERR_PTR(-EINVAL);
1320         }
1321
1322         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1323                 return ERR_PTR(-EINVAL);
1324
1325         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1326         if (!tz)
1327                 return ERR_PTR(-ENOMEM);
1328
1329         INIT_LIST_HEAD(&tz->thermal_instances);
1330         ida_init(&tz->ida);
1331         mutex_init(&tz->lock);
1332         id = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1333         if (id < 0) {
1334                 result = id;
1335                 goto free_tz;
1336         }
1337
1338         tz->id = id;
1339         strlcpy(tz->type, type, sizeof(tz->type));
1340         tz->ops = ops;
1341         tz->tzp = tzp;
1342         tz->device.class = &thermal_class;
1343         tz->devdata = devdata;
1344         tz->trips = trips;
1345         tz->passive_delay = passive_delay;
1346         tz->polling_delay = polling_delay;
1347
1348         /* sys I/F */
1349         /* Add nodes that are always present via .groups */
1350         result = thermal_zone_create_device_groups(tz, mask);
1351         if (result)
1352                 goto remove_id;
1353
1354         /* A new thermal zone needs to be updated anyway. */
1355         atomic_set(&tz->need_update, 1);
1356
1357         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1358         result = device_register(&tz->device);
1359         if (result)
1360                 goto release_device;
1361
1362         for (count = 0; count < trips; count++) {
1363                 if (tz->ops->get_trip_type(tz, count, &trip_type))
1364                         set_bit(count, &tz->trips_disabled);
1365                 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1366                         set_bit(count, &tz->trips_disabled);
1367                 /* Check for bogus trip points */
1368                 if (trip_temp == 0)
1369                         set_bit(count, &tz->trips_disabled);
1370         }
1371
1372         /* Update 'this' zone's governor information */
1373         mutex_lock(&thermal_governor_lock);
1374
1375         if (tz->tzp)
1376                 governor = __find_governor(tz->tzp->governor_name);
1377         else
1378                 governor = def_governor;
1379
1380         result = thermal_set_governor(tz, governor);
1381         if (result) {
1382                 mutex_unlock(&thermal_governor_lock);
1383                 goto unregister;
1384         }
1385
1386         mutex_unlock(&thermal_governor_lock);
1387
1388         if (!tz->tzp || !tz->tzp->no_hwmon) {
1389                 result = thermal_add_hwmon_sysfs(tz);
1390                 if (result)
1391                         goto unregister;
1392         }
1393
1394         mutex_lock(&thermal_list_lock);
1395         list_add_tail(&tz->node, &thermal_tz_list);
1396         mutex_unlock(&thermal_list_lock);
1397
1398         /* Bind cooling devices for this zone */
1399         bind_tz(tz);
1400
1401         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1402
1403         thermal_zone_device_reset(tz);
1404         /* Update the new thermal zone and mark it as already updated. */
1405         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1406                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1407
1408         return tz;
1409
1410 unregister:
1411         device_del(&tz->device);
1412 release_device:
1413         put_device(&tz->device);
1414         tz = NULL;
1415 remove_id:
1416         ida_simple_remove(&thermal_tz_ida, id);
1417 free_tz:
1418         kfree(tz);
1419         return ERR_PTR(result);
1420 }
1421 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1422
1423 /**
1424  * thermal_device_unregister - removes the registered thermal zone device
1425  * @tz: the thermal zone device to remove
1426  */
1427 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1428 {
1429         int i;
1430         const struct thermal_zone_params *tzp;
1431         struct thermal_cooling_device *cdev;
1432         struct thermal_zone_device *pos = NULL;
1433
1434         if (!tz)
1435                 return;
1436
1437         tzp = tz->tzp;
1438
1439         mutex_lock(&thermal_list_lock);
1440         list_for_each_entry(pos, &thermal_tz_list, node)
1441                 if (pos == tz)
1442                         break;
1443         if (pos != tz) {
1444                 /* thermal zone device not found */
1445                 mutex_unlock(&thermal_list_lock);
1446                 return;
1447         }
1448         list_del(&tz->node);
1449
1450         /* Unbind all cdevs associated with 'this' thermal zone */
1451         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1452                 if (tz->ops->unbind) {
1453                         tz->ops->unbind(tz, cdev);
1454                         continue;
1455                 }
1456
1457                 if (!tzp || !tzp->tbp)
1458                         break;
1459
1460                 for (i = 0; i < tzp->num_tbps; i++) {
1461                         if (tzp->tbp[i].cdev == cdev) {
1462                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1463                                 tzp->tbp[i].cdev = NULL;
1464                         }
1465                 }
1466         }
1467
1468         mutex_unlock(&thermal_list_lock);
1469
1470         cancel_delayed_work_sync(&tz->poll_queue);
1471
1472         thermal_set_governor(tz, NULL);
1473
1474         thermal_remove_hwmon_sysfs(tz);
1475         ida_simple_remove(&thermal_tz_ida, tz->id);
1476         ida_destroy(&tz->ida);
1477         mutex_destroy(&tz->lock);
1478         device_unregister(&tz->device);
1479 }
1480 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1481
1482 /**
1483  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1484  * @name: thermal zone name to fetch the temperature
1485  *
1486  * When only one zone is found with the passed name, returns a reference to it.
1487  *
1488  * Return: On success returns a reference to an unique thermal zone with
1489  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1490  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1491  */
1492 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1493 {
1494         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1495         unsigned int found = 0;
1496
1497         if (!name)
1498                 goto exit;
1499
1500         mutex_lock(&thermal_list_lock);
1501         list_for_each_entry(pos, &thermal_tz_list, node)
1502                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1503                         found++;
1504                         ref = pos;
1505                 }
1506         mutex_unlock(&thermal_list_lock);
1507
1508         /* nothing has been found, thus an error code for it */
1509         if (found == 0)
1510                 ref = ERR_PTR(-ENODEV);
1511         else if (found > 1)
1512         /* Success only when an unique zone is found */
1513                 ref = ERR_PTR(-EEXIST);
1514
1515 exit:
1516         return ref;
1517 }
1518 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1519
1520 static int thermal_pm_notify(struct notifier_block *nb,
1521                              unsigned long mode, void *_unused)
1522 {
1523         struct thermal_zone_device *tz;
1524
1525         switch (mode) {
1526         case PM_HIBERNATION_PREPARE:
1527         case PM_RESTORE_PREPARE:
1528         case PM_SUSPEND_PREPARE:
1529                 atomic_set(&in_suspend, 1);
1530                 break;
1531         case PM_POST_HIBERNATION:
1532         case PM_POST_RESTORE:
1533         case PM_POST_SUSPEND:
1534                 atomic_set(&in_suspend, 0);
1535                 list_for_each_entry(tz, &thermal_tz_list, node) {
1536                         if (!thermal_zone_device_is_enabled(tz))
1537                                 continue;
1538
1539                         thermal_zone_device_init(tz);
1540                         thermal_zone_device_update(tz,
1541                                                    THERMAL_EVENT_UNSPECIFIED);
1542                 }
1543                 break;
1544         default:
1545                 break;
1546         }
1547         return 0;
1548 }
1549
1550 static struct notifier_block thermal_pm_nb = {
1551         .notifier_call = thermal_pm_notify,
1552 };
1553
1554 static int __init thermal_init(void)
1555 {
1556         int result;
1557
1558         mutex_init(&poweroff_lock);
1559         result = thermal_register_governors();
1560         if (result)
1561                 goto error;
1562
1563         result = class_register(&thermal_class);
1564         if (result)
1565                 goto unregister_governors;
1566
1567         result = of_parse_thermal_zones();
1568         if (result)
1569                 goto unregister_class;
1570
1571         result = register_pm_notifier(&thermal_pm_nb);
1572         if (result)
1573                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1574                         result);
1575
1576         return 0;
1577
1578 unregister_class:
1579         class_unregister(&thermal_class);
1580 unregister_governors:
1581         thermal_unregister_governors();
1582 error:
1583         ida_destroy(&thermal_tz_ida);
1584         ida_destroy(&thermal_cdev_ida);
1585         mutex_destroy(&thermal_list_lock);
1586         mutex_destroy(&thermal_governor_lock);
1587         mutex_destroy(&poweroff_lock);
1588         return result;
1589 }
1590 core_initcall(thermal_init);