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/module.h>
  13 #include <linux/device.h>
  14 #include <linux/err.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 <net/netlink.h>
  23 #include <net/genetlink.h>
  24 #include <linux/suspend.h>
  25
  26 #define CREATE_TRACE_POINTS
  27 #include <trace/events/thermal.h>
  28
  29 #include "thermal_core.h"
  30 #include "thermal_hwmon.h"
  31
  32 MODULE_AUTHOR("Zhang Rui");
  33 MODULE_DESCRIPTION("Generic thermal management sysfs support");
  34 MODULE_LICENSE("GPL v2");
  35
  36 static DEFINE_IDA(thermal_tz_ida);
  37 static DEFINE_IDA(thermal_cdev_ida);
  38
  39 static LIST_HEAD(thermal_tz_list);
  40 static LIST_HEAD(thermal_cdev_list);
  41 static LIST_HEAD(thermal_governor_list);
  42
  43 static DEFINE_MUTEX(thermal_list_lock);
  44 static DEFINE_MUTEX(thermal_governor_lock);
  45 static DEFINE_MUTEX(poweroff_lock);
  46
  47 static atomic_t in_suspend;
  48 static bool power_off_triggered;
  49
  50 static struct thermal_governor *def_governor;
  51
  52 /*
  53  * Governor section: set of functions to handle thermal governors
  54  *
  55  * Functions to help in the life cycle of thermal governors within
  56  * the thermal core and by the thermal governor code.
  57  */
  58
  59 static struct thermal_governor *__find_governor(const char *name)
  60 {
  61         struct thermal_governor *pos;
  62
  63         if (!name || !name[0])
  64                 return def_governor;
  65
  66         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  67                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  68                         return pos;
  69
  70         return NULL;
  71 }
  72
  73 /**
  74  * bind_previous_governor() - bind the previous governor of the thermal zone
  75  * @tz:         a valid pointer to a struct thermal_zone_device
  76  * @failed_gov_name:    the name of the governor that failed to register
  77  *
  78  * Register the previous governor of the thermal zone after a new
  79  * governor has failed to be bound.
  80  */
  81 static void bind_previous_governor(struct thermal_zone_device *tz,
  82                                    const char *failed_gov_name)
  83 {
  84         if (tz->governor && tz->governor->bind_to_tz) {
  85                 if (tz->governor->bind_to_tz(tz)) {
  86                         dev_err(&tz->device,
  87                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  88                                 failed_gov_name, tz->governor->name, tz->type);
  89                         tz->governor = NULL;
  90                 }
  91         }
  92 }
  93
  94 /**
  95  * thermal_set_governor() - Switch to another governor
  96  * @tz:         a valid pointer to a struct thermal_zone_device
  97  * @new_gov:    pointer to the new governor
  98  *
  99  * Change the governor of thermal zone @tz.
 100  *
 101  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
 102  */
 103 static int thermal_set_governor(struct thermal_zone_device *tz,
 104                                 struct thermal_governor *new_gov)
 105 {
 106         int ret = 0;
 107
 108         if (tz->governor && tz->governor->unbind_from_tz)
 109                 tz->governor->unbind_from_tz(tz);
 110
 111         if (new_gov && new_gov->bind_to_tz) {
 112                 ret = new_gov->bind_to_tz(tz);
 113                 if (ret) {
 114                         bind_previous_governor(tz, new_gov->name);
 115
 116                         return ret;
 117                 }
 118         }
 119
 120         tz->governor = new_gov;
 121
 122         return ret;
 123 }
 124
 125 int thermal_register_governor(struct thermal_governor *governor)
 126 {
 127         int err;
 128         const char *name;
 129         struct thermal_zone_device *pos;
 130
 131         if (!governor)
 132                 return -EINVAL;
 133
 134         mutex_lock(&thermal_governor_lock);
 135
 136         err = -EBUSY;
 137         if (!__find_governor(governor->name)) {
 138                 bool match_default;
 139
 140                 err = 0;
 141                 list_add(&governor->governor_list, &thermal_governor_list);
 142                 match_default = !strncmp(governor->name,
 143                                          DEFAULT_THERMAL_GOVERNOR,
 144                                          THERMAL_NAME_LENGTH);
 145
 146                 if (!def_governor && match_default)
 147                         def_governor = governor;
 148         }
 149
 150         mutex_lock(&thermal_list_lock);
 151
 152         list_for_each_entry(pos, &thermal_tz_list, node) {
 153                 /*
 154                  * only thermal zones with specified tz->tzp->governor_name
 155                  * may run with tz->govenor unset
 156                  */
 157                 if (pos->governor)
 158                         continue;
 159
 160                 name = pos->tzp->governor_name;
 161
 162                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 163                         int ret;
 164
 165                         ret = thermal_set_governor(pos, governor);
 166                         if (ret)
 167                                 dev_err(&pos->device,
 168                                         "Failed to set governor %s for thermal zone %s: %d\n",
 169                                         governor->name, pos->type, ret);
 170                 }
 171         }
 172
 173         mutex_unlock(&thermal_list_lock);
 174         mutex_unlock(&thermal_governor_lock);
 175
 176         return err;
 177 }
 178
 179 void thermal_unregister_governor(struct thermal_governor *governor)
 180 {
 181         struct thermal_zone_device *pos;
 182
 183         if (!governor)
 184                 return;
 185
 186         mutex_lock(&thermal_governor_lock);
 187
 188         if (!__find_governor(governor->name))
 189                 goto exit;
 190
 191         mutex_lock(&thermal_list_lock);
 192
 193         list_for_each_entry(pos, &thermal_tz_list, node) {
 194                 if (!strncasecmp(pos->governor->name, governor->name,
 195                                  THERMAL_NAME_LENGTH))
 196                         thermal_set_governor(pos, NULL);
 197         }
 198
 199         mutex_unlock(&thermal_list_lock);
 200         list_del(&governor->governor_list);
 201 exit:
 202         mutex_unlock(&thermal_governor_lock);
 203 }
 204
 205 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 206                                    char *policy)
 207 {
 208         struct thermal_governor *gov;
 209         int ret = -EINVAL;
 210
 211         mutex_lock(&thermal_governor_lock);
 212         mutex_lock(&tz->lock);
 213
 214         gov = __find_governor(strim(policy));
 215         if (!gov)
 216                 goto exit;
 217
 218         ret = thermal_set_governor(tz, gov);
 219
 220 exit:
 221         mutex_unlock(&tz->lock);
 222         mutex_unlock(&thermal_governor_lock);
 223
 224         return ret;
 225 }
 226
 227 int thermal_build_list_of_policies(char *buf)
 228 {
 229         struct thermal_governor *pos;
 230         ssize_t count = 0;
 231         ssize_t size = PAGE_SIZE;
 232
 233         mutex_lock(&thermal_governor_lock);
 234
 235         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 236                 size = PAGE_SIZE - count;
 237                 count += scnprintf(buf + count, size, "%s ", pos->name);
 238         }
 239         count += scnprintf(buf + count, size, "\n");
 240
 241         mutex_unlock(&thermal_governor_lock);
 242
 243         return count;
 244 }
 245
 246 static int __init thermal_register_governors(void)
 247 {
 248         int result;
 249
 250         result = thermal_gov_step_wise_register();
 251         if (result)
 252                 return result;
 253
 254         result = thermal_gov_fair_share_register();
 255         if (result)
 256                 return result;
 257
 258         result = thermal_gov_bang_bang_register();
 259         if (result)
 260                 return result;
 261
 262         result = thermal_gov_user_space_register();
 263         if (result)
 264                 return result;
 265
 266         return thermal_gov_power_allocator_register();
 267 }
 268
 269 static void thermal_unregister_governors(void)
 270 {
 271         thermal_gov_step_wise_unregister();
 272         thermal_gov_fair_share_unregister();
 273         thermal_gov_bang_bang_unregister();
 274         thermal_gov_user_space_unregister();
 275         thermal_gov_power_allocator_unregister();
 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 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 /**
 327  * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
 328  * @work: work_struct associated with the emergency poweroff function
 329  *
 330  * This function is called in very critical situations to force
 331  * a kernel poweroff after a configurable timeout value.
 332  */
 333 static void thermal_emergency_poweroff_func(struct work_struct *work)
 334 {
 335         /*
 336          * We have reached here after the emergency thermal shutdown
 337          * Waiting period has expired. This means orderly_poweroff has
 338          * not been able to shut off the system for some reason.
 339          * Try to shut down the system immediately using kernel_power_off
 340          * if populated
 341          */
 342         WARN(1, "Attempting kernel_power_off: Temperature too high\n");
 343         kernel_power_off();
 344
 345         /*
 346          * Worst of the worst case trigger emergency restart
 347          */
 348         WARN(1, "Attempting emergency_restart: Temperature too high\n");
 349         emergency_restart();
 350 }
 351
 352 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
 353                             thermal_emergency_poweroff_func);
 354
 355 /**
 356  * thermal_emergency_poweroff - Trigger an emergency system poweroff
 357  *
 358  * This may be called from any critical situation to trigger a system shutdown
 359  * after a known period of time. By default this is not scheduled.
 360  */
 361 static void thermal_emergency_poweroff(void)
 362 {
 363         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 364         /*
 365          * poweroff_delay_ms must be a carefully profiled positive value.
 366          * Its a must for thermal_emergency_poweroff_work to be scheduled
 367          */
 368         if (poweroff_delay_ms <= 0)
 369                 return;
 370         schedule_delayed_work(&thermal_emergency_poweroff_work,
 371                               msecs_to_jiffies(poweroff_delay_ms));
 372 }
 373
 374 static void handle_critical_trips(struct thermal_zone_device *tz,
 375                                   int trip, enum thermal_trip_type trip_type)
 376 {
 377         int trip_temp;
 378
 379         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 380
 381         /* If we have not crossed the trip_temp, we do not care. */
 382         if (trip_temp <= 0 || tz->temperature < trip_temp)
 383                 return;
 384
 385         trace_thermal_zone_trip(tz, trip, trip_type);
 386
 387         if (tz->ops->notify)
 388                 tz->ops->notify(tz, trip, trip_type);
 389
 390         if (trip_type == THERMAL_TRIP_CRITICAL) {
 391                 dev_emerg(&tz->device,
 392                           "critical temperature reached (%d C), shutting down\n",
 393                           tz->temperature / 1000);
 394                 mutex_lock(&poweroff_lock);
 395                 if (!power_off_triggered) {
 396                         /*
 397                          * Queue a backup emergency shutdown in the event of
 398                          * orderly_poweroff failure
 399                          */
 400                         thermal_emergency_poweroff();
 401                         orderly_poweroff(true);
 402                         power_off_triggered = true;
 403                 }
 404                 mutex_unlock(&poweroff_lock);
 405         }
 406 }
 407
 408 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 409 {
 410         enum thermal_trip_type type;
 411
 412         /* Ignore disabled trip points */
 413         if (test_bit(trip, &tz->trips_disabled))
 414                 return;
 415
 416         tz->ops->get_trip_type(tz, trip, &type);
 417
 418         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 419                 handle_critical_trips(tz, trip, type);
 420         else
 421                 handle_non_critical_trips(tz, trip, type);
 422         /*
 423          * Alright, we handled this trip successfully.
 424          * So, start monitoring again.
 425          */
 426         monitor_thermal_zone(tz);
 427 }
 428
 429 static void update_temperature(struct thermal_zone_device *tz)
 430 {
 431         int temp, ret;
 432
 433         ret = thermal_zone_get_temp(tz, &temp);
 434         if (ret) {
 435                 if (ret != -EAGAIN)
 436                         dev_warn(&tz->device,
 437                                  "failed to read out thermal zone (%d)\n",
 438                                  ret);
 439                 return;
 440         }
 441
 442         mutex_lock(&tz->lock);
 443         tz->last_temperature = tz->temperature;
 444         tz->temperature = temp;
 445         mutex_unlock(&tz->lock);
 446
 447         trace_thermal_temperature(tz);
 448         if (tz->last_temperature == THERMAL_TEMP_INVALID)
 449                 dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n",
 450                         tz->temperature);
 451         else
 452                 dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
 453                         tz->last_temperature, tz->temperature);
 454 }
 455
 456 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 457 {
 458         struct thermal_instance *pos;
 459
 460         tz->temperature = THERMAL_TEMP_INVALID;
 461         tz->passive = 0;
 462         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 463                 pos->initialized = false;
 464 }
 465
 466 void thermal_zone_device_update(struct thermal_zone_device *tz,
 467                                 enum thermal_notify_event event)
 468 {
 469         int count;
 470
 471         if (atomic_read(&in_suspend))
 472                 return;
 473
 474         if (!tz->ops->get_temp)
 475                 return;
 476
 477         update_temperature(tz);
 478
 479         thermal_zone_set_trips(tz);
 480
 481         tz->notify_event = event;
 482
 483         for (count = 0; count < tz->trips; count++)
 484                 handle_thermal_trip(tz, count);
 485 }
 486 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 487
 488 /**
 489  * thermal_notify_framework - Sensor drivers use this API to notify framework
 490  * @tz:         thermal zone device
 491  * @trip:       indicates which trip point has been crossed
 492  *
 493  * This function handles the trip events from sensor drivers. It starts
 494  * throttling the cooling devices according to the policy configured.
 495  * For CRITICAL and HOT trip points, this notifies the respective drivers,
 496  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
 497  * The throttling policy is based on the configured platform data; if no
 498  * platform data is provided, this uses the step_wise throttling policy.
 499  */
 500 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
 501 {
 502         handle_thermal_trip(tz, trip);
 503 }
 504 EXPORT_SYMBOL_GPL(thermal_notify_framework);
 505
 506 static void thermal_zone_device_check(struct work_struct *work)
 507 {
 508         struct thermal_zone_device *tz = container_of(work, struct
 509                                                       thermal_zone_device,
 510                                                       poll_queue.work);
 511         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 512 }
 513
 514 /*
 515  * Power actor section: interface to power actors to estimate power
 516  *
 517  * Set of functions used to interact to cooling devices that know
 518  * how to estimate their devices power consumption.
 519  */
 520
 521 /**
 522  * power_actor_get_max_power() - get the maximum power that a cdev can consume
 523  * @cdev:       pointer to &thermal_cooling_device
 524  * @tz:         a valid thermal zone device pointer
 525  * @max_power:  pointer in which to store the maximum power
 526  *
 527  * Calculate the maximum power consumption in milliwats that the
 528  * cooling device can currently consume and store it in @max_power.
 529  *
 530  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 531  * power_actor API or -E* on other error.
 532  */
 533 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
 534                               struct thermal_zone_device *tz, u32 *max_power)
 535 {
 536         if (!cdev_is_power_actor(cdev))
 537                 return -EINVAL;
 538
 539         return cdev->ops->state2power(cdev, tz, 0, max_power);
 540 }
 541
 542 /**
 543  * power_actor_get_min_power() - get the mainimum power that a cdev can consume
 544  * @cdev:       pointer to &thermal_cooling_device
 545  * @tz:         a valid thermal zone device pointer
 546  * @min_power:  pointer in which to store the minimum power
 547  *
 548  * Calculate the minimum power consumption in milliwatts that the
 549  * cooling device can currently consume and store it in @min_power.
 550  *
 551  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 552  * power_actor API or -E* on other error.
 553  */
 554 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
 555                               struct thermal_zone_device *tz, u32 *min_power)
 556 {
 557         unsigned long max_state;
 558         int ret;
 559
 560         if (!cdev_is_power_actor(cdev))
 561                 return -EINVAL;
 562
 563         ret = cdev->ops->get_max_state(cdev, &max_state);
 564         if (ret)
 565                 return ret;
 566
 567         return cdev->ops->state2power(cdev, tz, max_state, min_power);
 568 }
 569
 570 /**
 571  * power_actor_set_power() - limit the maximum power a cooling device consumes
 572  * @cdev:       pointer to &thermal_cooling_device
 573  * @instance:   thermal instance to update
 574  * @power:      the power in milliwatts
 575  *
 576  * Set the cooling device to consume at most @power milliwatts. The limit is
 577  * expected to be a cap at the maximum power consumption.
 578  *
 579  * Return: 0 on success, -EINVAL if the cooling device does not
 580  * implement the power actor API or -E* for other failures.
 581  */
 582 int power_actor_set_power(struct thermal_cooling_device *cdev,
 583                           struct thermal_instance *instance, u32 power)
 584 {
 585         unsigned long state;
 586         int ret;
 587
 588         if (!cdev_is_power_actor(cdev))
 589                 return -EINVAL;
 590
 591         ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
 592         if (ret)
 593                 return ret;
 594
 595         instance->target = state;
 596         mutex_lock(&cdev->lock);
 597         cdev->updated = false;
 598         mutex_unlock(&cdev->lock);
 599         thermal_cdev_update(cdev);
 600
 601         return 0;
 602 }
 603
 604 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
 605                                           const char *cdev_type, size_t size)
 606 {
 607         struct thermal_cooling_device *cdev = NULL;
 608
 609         mutex_lock(&thermal_list_lock);
 610         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 611                 /* skip non matching cdevs */
 612                 if (strncmp(cdev_type, cdev->type, size))
 613                         continue;
 614
 615                 /* re binding the exception matching the type pattern */
 616                 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
 617                                                  THERMAL_NO_LIMIT,
 618                                                  THERMAL_NO_LIMIT,
 619                                                  THERMAL_WEIGHT_DEFAULT);
 620         }
 621         mutex_unlock(&thermal_list_lock);
 622 }
 623
 624 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
 625                                           const char *cdev_type, size_t size)
 626 {
 627         struct thermal_cooling_device *cdev = NULL;
 628
 629         mutex_lock(&thermal_list_lock);
 630         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 631                 /* skip non matching cdevs */
 632                 if (strncmp(cdev_type, cdev->type, size))
 633                         continue;
 634                 /* unbinding the exception matching the type pattern */
 635                 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
 636                                                    cdev);
 637         }
 638         mutex_unlock(&thermal_list_lock);
 639 }
 640
 641 /*
 642  * Device management section: cooling devices, zones devices, and binding
 643  *
 644  * Set of functions provided by the thermal core for:
 645  * - cooling devices lifecycle: registration, unregistration,
 646  *                              binding, and unbinding.
 647  * - thermal zone devices lifecycle: registration, unregistration,
 648  *                                   binding, and unbinding.
 649  */
 650
 651 /**
 652  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 653  * @tz:         pointer to struct thermal_zone_device
 654  * @trip:       indicates which trip point the cooling devices is
 655  *              associated with in this thermal zone.
 656  * @cdev:       pointer to struct thermal_cooling_device
 657  * @upper:      the Maximum cooling state for this trip point.
 658  *              THERMAL_NO_LIMIT means no upper limit,
 659  *              and the cooling device can be in max_state.
 660  * @lower:      the Minimum cooling state can be used for this trip point.
 661  *              THERMAL_NO_LIMIT means no lower limit,
 662  *              and the cooling device can be in cooling state 0.
 663  * @weight:     The weight of the cooling device to be bound to the
 664  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 665  *              default value
 666  *
 667  * This interface function bind a thermal cooling device to the certain trip
 668  * point of a thermal zone device.
 669  * This function is usually called in the thermal zone device .bind callback.
 670  *
 671  * Return: 0 on success, the proper error value otherwise.
 672  */
 673 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 674                                      int trip,
 675                                      struct thermal_cooling_device *cdev,
 676                                      unsigned long upper, unsigned long lower,
 677                                      unsigned int weight)
 678 {
 679         struct thermal_instance *dev;
 680         struct thermal_instance *pos;
 681         struct thermal_zone_device *pos1;
 682         struct thermal_cooling_device *pos2;
 683         unsigned long max_state;
 684         int result, ret;
 685
 686         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 687                 return -EINVAL;
 688
 689         list_for_each_entry(pos1, &thermal_tz_list, node) {
 690                 if (pos1 == tz)
 691                         break;
 692         }
 693         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 694                 if (pos2 == cdev)
 695                         break;
 696         }
 697
 698         if (tz != pos1 || cdev != pos2)
 699                 return -EINVAL;
 700
 701         ret = cdev->ops->get_max_state(cdev, &max_state);
 702         if (ret)
 703                 return ret;
 704
 705         /* lower default 0, upper default max_state */
 706         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 707         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 708
 709         if (lower > upper || upper > max_state)
 710                 return -EINVAL;
 711
 712         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 713         if (!dev)
 714                 return -ENOMEM;
 715         dev->tz = tz;
 716         dev->cdev = cdev;
 717         dev->trip = trip;
 718         dev->upper = upper;
 719         dev->lower = lower;
 720         dev->target = THERMAL_NO_TARGET;
 721         dev->weight = weight;
 722
 723         result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
 724         if (result < 0)
 725                 goto free_mem;
 726
 727         dev->id = result;
 728         sprintf(dev->name, "cdev%d", dev->id);
 729         result =
 730             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 731         if (result)
 732                 goto release_ida;
 733
 734         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 735         sysfs_attr_init(&dev->attr.attr);
 736         dev->attr.attr.name = dev->attr_name;
 737         dev->attr.attr.mode = 0444;
 738         dev->attr.show = trip_point_show;
 739         result = device_create_file(&tz->device, &dev->attr);
 740         if (result)
 741                 goto remove_symbol_link;
 742
 743         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 744         sysfs_attr_init(&dev->weight_attr.attr);
 745         dev->weight_attr.attr.name = dev->weight_attr_name;
 746         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 747         dev->weight_attr.show = weight_show;
 748         dev->weight_attr.store = weight_store;
 749         result = device_create_file(&tz->device, &dev->weight_attr);
 750         if (result)
 751                 goto remove_trip_file;
 752
 753         mutex_lock(&tz->lock);
 754         mutex_lock(&cdev->lock);
 755         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 756                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 757                         result = -EEXIST;
 758                         break;
 759                 }
 760         if (!result) {
 761                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 762                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 763                 atomic_set(&tz->need_update, 1);
 764         }
 765         mutex_unlock(&cdev->lock);
 766         mutex_unlock(&tz->lock);
 767
 768         if (!result)
 769                 return 0;
 770
 771         device_remove_file(&tz->device, &dev->weight_attr);
 772 remove_trip_file:
 773         device_remove_file(&tz->device, &dev->attr);
 774 remove_symbol_link:
 775         sysfs_remove_link(&tz->device.kobj, dev->name);
 776 release_ida:
 777         ida_simple_remove(&tz->ida, dev->id);
 778 free_mem:
 779         kfree(dev);
 780         return result;
 781 }
 782 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 783
 784 /**
 785  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 786  *                                        thermal zone.
 787  * @tz:         pointer to a struct thermal_zone_device.
 788  * @trip:       indicates which trip point the cooling devices is
 789  *              associated with in this thermal zone.
 790  * @cdev:       pointer to a struct thermal_cooling_device.
 791  *
 792  * This interface function unbind a thermal cooling device from the certain
 793  * trip point of a thermal zone device.
 794  * This function is usually called in the thermal zone device .unbind callback.
 795  *
 796  * Return: 0 on success, the proper error value otherwise.
 797  */
 798 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 799                                        int trip,
 800                                        struct thermal_cooling_device *cdev)
 801 {
 802         struct thermal_instance *pos, *next;
 803
 804         mutex_lock(&tz->lock);
 805         mutex_lock(&cdev->lock);
 806         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 807                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 808                         list_del(&pos->tz_node);
 809                         list_del(&pos->cdev_node);
 810                         mutex_unlock(&cdev->lock);
 811                         mutex_unlock(&tz->lock);
 812                         goto unbind;
 813                 }
 814         }
 815         mutex_unlock(&cdev->lock);
 816         mutex_unlock(&tz->lock);
 817
 818         return -ENODEV;
 819
 820 unbind:
 821         device_remove_file(&tz->device, &pos->weight_attr);
 822         device_remove_file(&tz->device, &pos->attr);
 823         sysfs_remove_link(&tz->device.kobj, pos->name);
 824         ida_simple_remove(&tz->ida, pos->id);
 825         kfree(pos);
 826         return 0;
 827 }
 828 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 829
 830 static void thermal_release(struct device *dev)
 831 {
 832         struct thermal_zone_device *tz;
 833         struct thermal_cooling_device *cdev;
 834
 835         if (!strncmp(dev_name(dev), "thermal_zone",
 836                      sizeof("thermal_zone") - 1)) {
 837                 tz = to_thermal_zone(dev);
 838                 thermal_zone_destroy_device_groups(tz);
 839                 kfree(tz);
 840         } else if (!strncmp(dev_name(dev), "cooling_device",
 841                             sizeof("cooling_device") - 1)) {
 842                 cdev = to_cooling_device(dev);
 843                 kfree(cdev);
 844         }
 845 }
 846
 847 static struct class thermal_class = {
 848         .name = "thermal",
 849         .dev_release = thermal_release,
 850 };
 851
 852 static inline
 853 void print_bind_err_msg(struct thermal_zone_device *tz,
 854                         struct thermal_cooling_device *cdev, int ret)
 855 {
 856         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 857                 tz->type, cdev->type, ret);
 858 }
 859
 860 static void __bind(struct thermal_zone_device *tz, int mask,
 861                    struct thermal_cooling_device *cdev,
 862                    unsigned long *limits,
 863                    unsigned int weight)
 864 {
 865         int i, ret;
 866
 867         for (i = 0; i < tz->trips; i++) {
 868                 if (mask & (1 << i)) {
 869                         unsigned long upper, lower;
 870
 871                         upper = THERMAL_NO_LIMIT;
 872                         lower = THERMAL_NO_LIMIT;
 873                         if (limits) {
 874                                 lower = limits[i * 2];
 875                                 upper = limits[i * 2 + 1];
 876                         }
 877                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 878                                                                upper, lower,
 879                                                                weight);
 880                         if (ret)
 881                                 print_bind_err_msg(tz, cdev, ret);
 882                 }
 883         }
 884 }
 885
 886 static void bind_cdev(struct thermal_cooling_device *cdev)
 887 {
 888         int i, ret;
 889         const struct thermal_zone_params *tzp;
 890         struct thermal_zone_device *pos = NULL;
 891
 892         mutex_lock(&thermal_list_lock);
 893
 894         list_for_each_entry(pos, &thermal_tz_list, node) {
 895                 if (!pos->tzp && !pos->ops->bind)
 896                         continue;
 897
 898                 if (pos->ops->bind) {
 899                         ret = pos->ops->bind(pos, cdev);
 900                         if (ret)
 901                                 print_bind_err_msg(pos, cdev, ret);
 902                         continue;
 903                 }
 904
 905                 tzp = pos->tzp;
 906                 if (!tzp || !tzp->tbp)
 907                         continue;
 908
 909                 for (i = 0; i < tzp->num_tbps; i++) {
 910                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 911                                 continue;
 912                         if (tzp->tbp[i].match(pos, cdev))
 913                                 continue;
 914                         tzp->tbp[i].cdev = cdev;
 915                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 916                                tzp->tbp[i].binding_limits,
 917                                tzp->tbp[i].weight);
 918                 }
 919         }
 920
 921         mutex_unlock(&thermal_list_lock);
 922 }
 923
 924 /**
 925  * __thermal_cooling_device_register() - register a new thermal cooling device
 926  * @np:         a pointer to a device tree node.
 927  * @type:       the thermal cooling device type.
 928  * @devdata:    device private data.
 929  * @ops:                standard thermal cooling devices callbacks.
 930  *
 931  * This interface function adds a new thermal cooling device (fan/processor/...)
 932  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 933  * to all the thermal zone devices registered at the same time.
 934  * It also gives the opportunity to link the cooling device to a device tree
 935  * node, so that it can be bound to a thermal zone created out of device tree.
 936  *
 937  * Return: a pointer to the created struct thermal_cooling_device or an
 938  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 939  */
 940 static struct thermal_cooling_device *
 941 __thermal_cooling_device_register(struct device_node *np,
 942                                   char *type, void *devdata,
 943                                   const struct thermal_cooling_device_ops *ops)
 944 {
 945         struct thermal_cooling_device *cdev;
 946         struct thermal_zone_device *pos = NULL;
 947         int result;
 948
 949         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
 950                 return ERR_PTR(-EINVAL);
 951
 952         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 953             !ops->set_cur_state)
 954                 return ERR_PTR(-EINVAL);
 955
 956         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 957         if (!cdev)
 958                 return ERR_PTR(-ENOMEM);
 959
 960         result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
 961         if (result < 0) {
 962                 kfree(cdev);
 963                 return ERR_PTR(result);
 964         }
 965
 966         cdev->id = result;
 967         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
 968         mutex_init(&cdev->lock);
 969         INIT_LIST_HEAD(&cdev->thermal_instances);
 970         cdev->np = np;
 971         cdev->ops = ops;
 972         cdev->updated = false;
 973         cdev->device.class = &thermal_class;
 974         cdev->devdata = devdata;
 975         thermal_cooling_device_setup_sysfs(cdev);
 976         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 977         result = device_register(&cdev->device);
 978         if (result) {
 979                 ida_simple_remove(&thermal_cdev_ida, cdev->id);
 980                 kfree(cdev);
 981                 return ERR_PTR(result);
 982         }
 983
 984         /* Add 'this' new cdev to the global cdev list */
 985         mutex_lock(&thermal_list_lock);
 986         list_add(&cdev->node, &thermal_cdev_list);
 987         mutex_unlock(&thermal_list_lock);
 988
 989         /* Update binding information for 'this' new cdev */
 990         bind_cdev(cdev);
 991
 992         mutex_lock(&thermal_list_lock);
 993         list_for_each_entry(pos, &thermal_tz_list, node)
 994                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
 995                         thermal_zone_device_update(pos,
 996                                                    THERMAL_EVENT_UNSPECIFIED);
 997         mutex_unlock(&thermal_list_lock);
 998
 999         return cdev;
1000 }
1001
1002 /**
1003  * thermal_cooling_device_register() - register a new thermal cooling device
1004  * @type:       the thermal cooling device type.
1005  * @devdata:    device private data.
1006  * @ops:                standard thermal cooling devices callbacks.
1007  *
1008  * This interface function adds a new thermal cooling device (fan/processor/...)
1009  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1010  * to all the thermal zone devices registered at the same time.
1011  *
1012  * Return: a pointer to the created struct thermal_cooling_device or an
1013  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1014  */
1015 struct thermal_cooling_device *
1016 thermal_cooling_device_register(char *type, void *devdata,
1017                                 const struct thermal_cooling_device_ops *ops)
1018 {
1019         return __thermal_cooling_device_register(NULL, type, devdata, ops);
1020 }
1021 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1022
1023 /**
1024  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1025  * @np:         a pointer to a device tree node.
1026  * @type:       the thermal cooling device type.
1027  * @devdata:    device private data.
1028  * @ops:                standard thermal cooling devices callbacks.
1029  *
1030  * This function will register a cooling device with device tree node reference.
1031  * This interface function adds a new thermal cooling device (fan/processor/...)
1032  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1033  * to all the thermal zone devices registered at the same time.
1034  *
1035  * Return: a pointer to the created struct thermal_cooling_device or an
1036  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1037  */
1038 struct thermal_cooling_device *
1039 thermal_of_cooling_device_register(struct device_node *np,
1040                                    char *type, void *devdata,
1041                                    const struct thermal_cooling_device_ops *ops)
1042 {
1043         return __thermal_cooling_device_register(np, type, devdata, ops);
1044 }
1045 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1046
1047 static void __unbind(struct thermal_zone_device *tz, int mask,
1048                      struct thermal_cooling_device *cdev)
1049 {
1050         int i;
1051
1052         for (i = 0; i < tz->trips; i++)
1053                 if (mask & (1 << i))
1054                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1055 }
1056
1057 /**
1058  * thermal_cooling_device_unregister - removes a thermal cooling device
1059  * @cdev:       the thermal cooling device to remove.
1060  *
1061  * thermal_cooling_device_unregister() must be called when a registered
1062  * thermal cooling device is no longer needed.
1063  */
1064 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1065 {
1066         int i;
1067         const struct thermal_zone_params *tzp;
1068         struct thermal_zone_device *tz;
1069         struct thermal_cooling_device *pos = NULL;
1070
1071         if (!cdev)
1072                 return;
1073
1074         mutex_lock(&thermal_list_lock);
1075         list_for_each_entry(pos, &thermal_cdev_list, node)
1076                 if (pos == cdev)
1077                         break;
1078         if (pos != cdev) {
1079                 /* thermal cooling device not found */
1080                 mutex_unlock(&thermal_list_lock);
1081                 return;
1082         }
1083         list_del(&cdev->node);
1084
1085         /* Unbind all thermal zones associated with 'this' cdev */
1086         list_for_each_entry(tz, &thermal_tz_list, node) {
1087                 if (tz->ops->unbind) {
1088                         tz->ops->unbind(tz, cdev);
1089                         continue;
1090                 }
1091
1092                 if (!tz->tzp || !tz->tzp->tbp)
1093                         continue;
1094
1095                 tzp = tz->tzp;
1096                 for (i = 0; i < tzp->num_tbps; i++) {
1097                         if (tzp->tbp[i].cdev == cdev) {
1098                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1099                                 tzp->tbp[i].cdev = NULL;
1100                         }
1101                 }
1102         }
1103
1104         mutex_unlock(&thermal_list_lock);
1105
1106         ida_simple_remove(&thermal_cdev_ida, cdev->id);
1107         device_del(&cdev->device);
1108         thermal_cooling_device_destroy_sysfs(cdev);
1109         put_device(&cdev->device);
1110 }
1111 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1112
1113 static void bind_tz(struct thermal_zone_device *tz)
1114 {
1115         int i, ret;
1116         struct thermal_cooling_device *pos = NULL;
1117         const struct thermal_zone_params *tzp = tz->tzp;
1118
1119         if (!tzp && !tz->ops->bind)
1120                 return;
1121
1122         mutex_lock(&thermal_list_lock);
1123
1124         /* If there is ops->bind, try to use ops->bind */
1125         if (tz->ops->bind) {
1126                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1127                         ret = tz->ops->bind(tz, pos);
1128                         if (ret)
1129                                 print_bind_err_msg(tz, pos, ret);
1130                 }
1131                 goto exit;
1132         }
1133
1134         if (!tzp || !tzp->tbp)
1135                 goto exit;
1136
1137         list_for_each_entry(pos, &thermal_cdev_list, node) {
1138                 for (i = 0; i < tzp->num_tbps; i++) {
1139                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1140                                 continue;
1141                         if (tzp->tbp[i].match(tz, pos))
1142                                 continue;
1143                         tzp->tbp[i].cdev = pos;
1144                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1145                                tzp->tbp[i].binding_limits,
1146                                tzp->tbp[i].weight);
1147                 }
1148         }
1149 exit:
1150         mutex_unlock(&thermal_list_lock);
1151 }
1152
1153 /**
1154  * thermal_zone_device_register() - register a new thermal zone device
1155  * @type:       the thermal zone device type
1156  * @trips:      the number of trip points the thermal zone support
1157  * @mask:       a bit string indicating the writeablility of trip points
1158  * @devdata:    private device data
1159  * @ops:        standard thermal zone device callbacks
1160  * @tzp:        thermal zone platform parameters
1161  * @passive_delay: number of milliseconds to wait between polls when
1162  *                 performing passive cooling
1163  * @polling_delay: number of milliseconds to wait between polls when checking
1164  *                 whether trip points have been crossed (0 for interrupt
1165  *                 driven systems)
1166  *
1167  * This interface function adds a new thermal zone device (sensor) to
1168  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1169  * thermal cooling devices registered at the same time.
1170  * thermal_zone_device_unregister() must be called when the device is no
1171  * longer needed. The passive cooling depends on the .get_trend() return value.
1172  *
1173  * Return: a pointer to the created struct thermal_zone_device or an
1174  * in case of error, an ERR_PTR. Caller must check return value with
1175  * IS_ERR*() helpers.
1176  */
1177 struct thermal_zone_device *
1178 thermal_zone_device_register(const char *type, int trips, int mask,
1179                              void *devdata, struct thermal_zone_device_ops *ops,
1180                              struct thermal_zone_params *tzp, int passive_delay,
1181                              int polling_delay)
1182 {
1183         struct thermal_zone_device *tz;
1184         enum thermal_trip_type trip_type;
1185         int trip_temp;
1186         int result;
1187         int count;
1188         struct thermal_governor *governor;
1189
1190         if (!type || strlen(type) == 0)
1191                 return ERR_PTR(-EINVAL);
1192
1193         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1194                 return ERR_PTR(-EINVAL);
1195
1196         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
1197                 return ERR_PTR(-EINVAL);
1198
1199         if (!ops)
1200                 return ERR_PTR(-EINVAL);
1201
1202         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1203                 return ERR_PTR(-EINVAL);
1204
1205         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1206         if (!tz)
1207                 return ERR_PTR(-ENOMEM);
1208
1209         INIT_LIST_HEAD(&tz->thermal_instances);
1210         ida_init(&tz->ida);
1211         mutex_init(&tz->lock);
1212         result = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1213         if (result < 0)
1214                 goto free_tz;
1215
1216         tz->id = result;
1217         strlcpy(tz->type, type, sizeof(tz->type));
1218         tz->ops = ops;
1219         tz->tzp = tzp;
1220         tz->device.class = &thermal_class;
1221         tz->devdata = devdata;
1222         tz->trips = trips;
1223         tz->passive_delay = passive_delay;
1224         tz->polling_delay = polling_delay;
1225
1226         /* sys I/F */
1227         /* Add nodes that are always present via .groups */
1228         result = thermal_zone_create_device_groups(tz, mask);
1229         if (result)
1230                 goto remove_id;
1231
1232         /* A new thermal zone needs to be updated anyway. */
1233         atomic_set(&tz->need_update, 1);
1234
1235         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1236         result = device_register(&tz->device);
1237         if (result)
1238                 goto remove_device_groups;
1239
1240         for (count = 0; count < trips; count++) {
1241                 if (tz->ops->get_trip_type(tz, count, &trip_type))
1242                         set_bit(count, &tz->trips_disabled);
1243                 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1244                         set_bit(count, &tz->trips_disabled);
1245                 /* Check for bogus trip points */
1246                 if (trip_temp == 0)
1247                         set_bit(count, &tz->trips_disabled);
1248         }
1249
1250         /* Update 'this' zone's governor information */
1251         mutex_lock(&thermal_governor_lock);
1252
1253         if (tz->tzp)
1254                 governor = __find_governor(tz->tzp->governor_name);
1255         else
1256                 governor = def_governor;
1257
1258         result = thermal_set_governor(tz, governor);
1259         if (result) {
1260                 mutex_unlock(&thermal_governor_lock);
1261                 goto unregister;
1262         }
1263
1264         mutex_unlock(&thermal_governor_lock);
1265
1266         if (!tz->tzp || !tz->tzp->no_hwmon) {
1267                 result = thermal_add_hwmon_sysfs(tz);
1268                 if (result)
1269                         goto unregister;
1270         }
1271
1272         mutex_lock(&thermal_list_lock);
1273         list_add_tail(&tz->node, &thermal_tz_list);
1274         mutex_unlock(&thermal_list_lock);
1275
1276         /* Bind cooling devices for this zone */
1277         bind_tz(tz);
1278
1279         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1280
1281         thermal_zone_device_reset(tz);
1282         /* Update the new thermal zone and mark it as already updated. */
1283         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1284                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1285
1286         return tz;
1287
1288 unregister:
1289         ida_simple_remove(&thermal_tz_ida, tz->id);
1290         device_unregister(&tz->device);
1291         return ERR_PTR(result);
1292
1293 remove_device_groups:
1294         thermal_zone_destroy_device_groups(tz);
1295 remove_id:
1296         ida_simple_remove(&thermal_tz_ida, tz->id);
1297 free_tz:
1298         kfree(tz);
1299         return ERR_PTR(result);
1300 }
1301 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1302
1303 /**
1304  * thermal_device_unregister - removes the registered thermal zone device
1305  * @tz: the thermal zone device to remove
1306  */
1307 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1308 {
1309         int i;
1310         const struct thermal_zone_params *tzp;
1311         struct thermal_cooling_device *cdev;
1312         struct thermal_zone_device *pos = NULL;
1313
1314         if (!tz)
1315                 return;
1316
1317         tzp = tz->tzp;
1318
1319         mutex_lock(&thermal_list_lock);
1320         list_for_each_entry(pos, &thermal_tz_list, node)
1321                 if (pos == tz)
1322                         break;
1323         if (pos != tz) {
1324                 /* thermal zone device not found */
1325                 mutex_unlock(&thermal_list_lock);
1326                 return;
1327         }
1328         list_del(&tz->node);
1329
1330         /* Unbind all cdevs associated with 'this' thermal zone */
1331         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1332                 if (tz->ops->unbind) {
1333                         tz->ops->unbind(tz, cdev);
1334                         continue;
1335                 }
1336
1337                 if (!tzp || !tzp->tbp)
1338                         break;
1339
1340                 for (i = 0; i < tzp->num_tbps; i++) {
1341                         if (tzp->tbp[i].cdev == cdev) {
1342                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1343                                 tzp->tbp[i].cdev = NULL;
1344                         }
1345                 }
1346         }
1347
1348         mutex_unlock(&thermal_list_lock);
1349
1350         thermal_zone_device_set_polling(tz, 0);
1351
1352         thermal_set_governor(tz, NULL);
1353
1354         thermal_remove_hwmon_sysfs(tz);
1355         ida_simple_remove(&thermal_tz_ida, tz->id);
1356         ida_destroy(&tz->ida);
1357         mutex_destroy(&tz->lock);
1358         device_unregister(&tz->device);
1359 }
1360 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1361
1362 /**
1363  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1364  * @name: thermal zone name to fetch the temperature
1365  *
1366  * When only one zone is found with the passed name, returns a reference to it.
1367  *
1368  * Return: On success returns a reference to an unique thermal zone with
1369  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1370  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1371  */
1372 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1373 {
1374         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1375         unsigned int found = 0;
1376
1377         if (!name)
1378                 goto exit;
1379
1380         mutex_lock(&thermal_list_lock);
1381         list_for_each_entry(pos, &thermal_tz_list, node)
1382                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1383                         found++;
1384                         ref = pos;
1385                 }
1386         mutex_unlock(&thermal_list_lock);
1387
1388         /* nothing has been found, thus an error code for it */
1389         if (found == 0)
1390                 ref = ERR_PTR(-ENODEV);
1391         else if (found > 1)
1392         /* Success only when an unique zone is found */
1393                 ref = ERR_PTR(-EEXIST);
1394
1395 exit:
1396         return ref;
1397 }
1398 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1399
1400 #ifdef CONFIG_NET
1401 static const struct genl_multicast_group thermal_event_mcgrps[] = {
1402         { .name = THERMAL_GENL_MCAST_GROUP_NAME, },
1403 };
1404
1405 static struct genl_family thermal_event_genl_family __ro_after_init = {
1406         .module = THIS_MODULE,
1407         .name = THERMAL_GENL_FAMILY_NAME,
1408         .version = THERMAL_GENL_VERSION,
1409         .maxattr = THERMAL_GENL_ATTR_MAX,
1410         .mcgrps = thermal_event_mcgrps,
1411         .n_mcgrps = ARRAY_SIZE(thermal_event_mcgrps),
1412 };
1413
1414 int thermal_generate_netlink_event(struct thermal_zone_device *tz,
1415                                    enum events event)
1416 {
1417         struct sk_buff *skb;
1418         struct nlattr *attr;
1419         struct thermal_genl_event *thermal_event;
1420         void *msg_header;
1421         int size;
1422         int result;
1423         static unsigned int thermal_event_seqnum;
1424
1425         if (!tz)
1426                 return -EINVAL;
1427
1428         /* allocate memory */
1429         size = nla_total_size(sizeof(struct thermal_genl_event)) +
1430                nla_total_size(0);
1431
1432         skb = genlmsg_new(size, GFP_ATOMIC);
1433         if (!skb)
1434                 return -ENOMEM;
1435
1436         /* add the genetlink message header */
1437         msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++,
1438                                  &thermal_event_genl_family, 0,
1439                                  THERMAL_GENL_CMD_EVENT);
1440         if (!msg_header) {
1441                 nlmsg_free(skb);
1442                 return -ENOMEM;
1443         }
1444
1445         /* fill the data */
1446         attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT,
1447                            sizeof(struct thermal_genl_event));
1448
1449         if (!attr) {
1450                 nlmsg_free(skb);
1451                 return -EINVAL;
1452         }
1453
1454         thermal_event = nla_data(attr);
1455         if (!thermal_event) {
1456                 nlmsg_free(skb);
1457                 return -EINVAL;
1458         }
1459
1460         memset(thermal_event, 0, sizeof(struct thermal_genl_event));
1461
1462         thermal_event->orig = tz->id;
1463         thermal_event->event = event;
1464
1465         /* send multicast genetlink message */
1466         genlmsg_end(skb, msg_header);
1467
1468         result = genlmsg_multicast(&thermal_event_genl_family, skb, 0,
1469                                    0, GFP_ATOMIC);
1470         if (result)
1471                 dev_err(&tz->device, "Failed to send netlink event:%d", result);
1472
1473         return result;
1474 }
1475 EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
1476
1477 static int __init genetlink_init(void)
1478 {
1479         return genl_register_family(&thermal_event_genl_family);
1480 }
1481
1482 static void genetlink_exit(void)
1483 {
1484         genl_unregister_family(&thermal_event_genl_family);
1485 }
1486 #else /* !CONFIG_NET */
1487 static inline int genetlink_init(void) { return 0; }
1488 static inline void genetlink_exit(void) {}
1489 #endif /* !CONFIG_NET */
1490
1491 static int thermal_pm_notify(struct notifier_block *nb,
1492                              unsigned long mode, void *_unused)
1493 {
1494         struct thermal_zone_device *tz;
1495
1496         switch (mode) {
1497         case PM_HIBERNATION_PREPARE:
1498         case PM_RESTORE_PREPARE:
1499         case PM_SUSPEND_PREPARE:
1500                 atomic_set(&in_suspend, 1);
1501                 break;
1502         case PM_POST_HIBERNATION:
1503         case PM_POST_RESTORE:
1504         case PM_POST_SUSPEND:
1505                 atomic_set(&in_suspend, 0);
1506                 list_for_each_entry(tz, &thermal_tz_list, node) {
1507                         thermal_zone_device_reset(tz);
1508                         thermal_zone_device_update(tz,
1509                                                    THERMAL_EVENT_UNSPECIFIED);
1510                 }
1511                 break;
1512         default:
1513                 break;
1514         }
1515         return 0;
1516 }
1517
1518 static struct notifier_block thermal_pm_nb = {
1519         .notifier_call = thermal_pm_notify,
1520 };
1521
1522 static int __init thermal_init(void)
1523 {
1524         int result;
1525
1526         mutex_init(&poweroff_lock);
1527         result = thermal_register_governors();
1528         if (result)
1529                 goto error;
1530
1531         result = class_register(&thermal_class);
1532         if (result)
1533                 goto unregister_governors;
1534
1535         result = genetlink_init();
1536         if (result)
1537                 goto unregister_class;
1538
1539         result = of_parse_thermal_zones();
1540         if (result)
1541                 goto exit_netlink;
1542
1543         result = register_pm_notifier(&thermal_pm_nb);
1544         if (result)
1545                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1546                         result);
1547
1548         return 0;
1549
1550 exit_netlink:
1551         genetlink_exit();
1552 unregister_class:
1553         class_unregister(&thermal_class);
1554 unregister_governors:
1555         thermal_unregister_governors();
1556 error:
1557         ida_destroy(&thermal_tz_ida);
1558         ida_destroy(&thermal_cdev_ida);
1559         mutex_destroy(&thermal_list_lock);
1560         mutex_destroy(&thermal_governor_lock);
1561         mutex_destroy(&poweroff_lock);
1562         return result;
1563 }
1564
1565 static void __exit thermal_exit(void)
1566 {
1567         unregister_pm_notifier(&thermal_pm_nb);
1568         of_thermal_destroy_zones();
1569         genetlink_exit();
1570         class_unregister(&thermal_class);
1571         thermal_unregister_governors();
1572         ida_destroy(&thermal_tz_ida);
1573         ida_destroy(&thermal_cdev_ida);
1574         mutex_destroy(&thermal_list_lock);
1575         mutex_destroy(&thermal_governor_lock);
1576 }
1577
1578 fs_initcall(thermal_init);
1579 module_exit(thermal_exit);