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, int trip)
 319 {
 320         tz->governor ? tz->governor->throttle(tz, trip) :
 321                        def_governor->throttle(tz, trip);
 322 }
 323
 324 /**
 325  * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
 326  * @work: work_struct associated with the emergency poweroff function
 327  *
 328  * This function is called in very critical situations to force
 329  * a kernel poweroff after a configurable timeout value.
 330  */
 331 static void thermal_emergency_poweroff_func(struct work_struct *work)
 332 {
 333         /*
 334          * We have reached here after the emergency thermal shutdown
 335          * Waiting period has expired. This means orderly_poweroff has
 336          * not been able to shut off the system for some reason.
 337          * Try to shut down the system immediately using kernel_power_off
 338          * if populated
 339          */
 340         WARN(1, "Attempting kernel_power_off: Temperature too high\n");
 341         kernel_power_off();
 342
 343         /*
 344          * Worst of the worst case trigger emergency restart
 345          */
 346         WARN(1, "Attempting emergency_restart: Temperature too high\n");
 347         emergency_restart();
 348 }
 349
 350 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
 351                             thermal_emergency_poweroff_func);
 352
 353 /**
 354  * thermal_emergency_poweroff - Trigger an emergency system poweroff
 355  *
 356  * This may be called from any critical situation to trigger a system shutdown
 357  * after a known period of time. By default this is not scheduled.
 358  */
 359 static void thermal_emergency_poweroff(void)
 360 {
 361         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 362         /*
 363          * poweroff_delay_ms must be a carefully profiled positive value.
 364          * Its a must for thermal_emergency_poweroff_work to be scheduled
 365          */
 366         if (poweroff_delay_ms <= 0)
 367                 return;
 368         schedule_delayed_work(&thermal_emergency_poweroff_work,
 369                               msecs_to_jiffies(poweroff_delay_ms));
 370 }
 371
 372 static void handle_critical_trips(struct thermal_zone_device *tz,
 373                                   int trip, enum thermal_trip_type trip_type)
 374 {
 375         int trip_temp;
 376
 377         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 378
 379         /* If we have not crossed the trip_temp, we do not care. */
 380         if (trip_temp <= 0 || tz->temperature < trip_temp)
 381                 return;
 382
 383         trace_thermal_zone_trip(tz, trip, trip_type);
 384
 385         if (tz->ops->notify)
 386                 tz->ops->notify(tz, trip, trip_type);
 387
 388         if (trip_type == THERMAL_TRIP_CRITICAL) {
 389                 dev_emerg(&tz->device,
 390                           "critical temperature reached (%d C), shutting down\n",
 391                           tz->temperature / 1000);
 392                 mutex_lock(&poweroff_lock);
 393                 if (!power_off_triggered) {
 394                         /*
 395                          * Queue a backup emergency shutdown in the event of
 396                          * orderly_poweroff failure
 397                          */
 398                         thermal_emergency_poweroff();
 399                         orderly_poweroff(true);
 400                         power_off_triggered = true;
 401                 }
 402                 mutex_unlock(&poweroff_lock);
 403         }
 404 }
 405
 406 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 407 {
 408         enum thermal_trip_type type;
 409
 410         /* Ignore disabled trip points */
 411         if (test_bit(trip, &tz->trips_disabled))
 412                 return;
 413
 414         tz->ops->get_trip_type(tz, trip, &type);
 415
 416         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 417                 handle_critical_trips(tz, trip, type);
 418         else
 419                 handle_non_critical_trips(tz, trip);
 420         /*
 421          * Alright, we handled this trip successfully.
 422          * So, start monitoring again.
 423          */
 424         monitor_thermal_zone(tz);
 425 }
 426
 427 static void update_temperature(struct thermal_zone_device *tz)
 428 {
 429         int temp, ret;
 430
 431         ret = thermal_zone_get_temp(tz, &temp);
 432         if (ret) {
 433                 if (ret != -EAGAIN)
 434                         dev_warn(&tz->device,
 435                                  "failed to read out thermal zone (%d)\n",
 436                                  ret);
 437                 return;
 438         }
 439
 440         mutex_lock(&tz->lock);
 441         tz->last_temperature = tz->temperature;
 442         tz->temperature = temp;
 443         mutex_unlock(&tz->lock);
 444
 445         trace_thermal_temperature(tz);
 446         if (tz->last_temperature == THERMAL_TEMP_INVALID)
 447                 dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n",
 448                         tz->temperature);
 449         else
 450                 dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
 451                         tz->last_temperature, tz->temperature);
 452 }
 453
 454 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 455 {
 456         struct thermal_instance *pos;
 457         tz->temperature = THERMAL_TEMP_INVALID;
 458         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 459                 pos->initialized = false;
 460 }
 461
 462 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 463 {
 464         tz->passive = 0;
 465         thermal_zone_device_init(tz);
 466 }
 467
 468 void thermal_zone_device_update(struct thermal_zone_device *tz,
 469                                 enum thermal_notify_event event)
 470 {
 471         int count;
 472
 473         if (atomic_read(&in_suspend))
 474                 return;
 475
 476         if (!tz->ops->get_temp)
 477                 return;
 478
 479         update_temperature(tz);
 480
 481         thermal_zone_set_trips(tz);
 482
 483         tz->notify_event = event;
 484
 485         for (count = 0; count < tz->trips; count++)
 486                 handle_thermal_trip(tz, count);
 487 }
 488 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 489
 490 /**
 491  * thermal_notify_framework - Sensor drivers use this API to notify framework
 492  * @tz:         thermal zone device
 493  * @trip:       indicates which trip point has been crossed
 494  *
 495  * This function handles the trip events from sensor drivers. It starts
 496  * throttling the cooling devices according to the policy configured.
 497  * For CRITICAL and HOT trip points, this notifies the respective drivers,
 498  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
 499  * The throttling policy is based on the configured platform data; if no
 500  * platform data is provided, this uses the step_wise throttling policy.
 501  */
 502 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
 503 {
 504         handle_thermal_trip(tz, trip);
 505 }
 506 EXPORT_SYMBOL_GPL(thermal_notify_framework);
 507
 508 static void thermal_zone_device_check(struct work_struct *work)
 509 {
 510         struct thermal_zone_device *tz = container_of(work, struct
 511                                                       thermal_zone_device,
 512                                                       poll_queue.work);
 513         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 514 }
 515
 516 /*
 517  * Power actor section: interface to power actors to estimate power
 518  *
 519  * Set of functions used to interact to cooling devices that know
 520  * how to estimate their devices power consumption.
 521  */
 522
 523 /**
 524  * power_actor_get_max_power() - get the maximum power that a cdev can consume
 525  * @cdev:       pointer to &thermal_cooling_device
 526  * @tz:         a valid thermal zone device pointer
 527  * @max_power:  pointer in which to store the maximum power
 528  *
 529  * Calculate the maximum power consumption in milliwats that the
 530  * cooling device can currently consume and store it in @max_power.
 531  *
 532  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 533  * power_actor API or -E* on other error.
 534  */
 535 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
 536                               struct thermal_zone_device *tz, u32 *max_power)
 537 {
 538         if (!cdev_is_power_actor(cdev))
 539                 return -EINVAL;
 540
 541         return cdev->ops->state2power(cdev, tz, 0, max_power);
 542 }
 543
 544 /**
 545  * power_actor_get_min_power() - get the mainimum power that a cdev can consume
 546  * @cdev:       pointer to &thermal_cooling_device
 547  * @tz:         a valid thermal zone device pointer
 548  * @min_power:  pointer in which to store the minimum power
 549  *
 550  * Calculate the minimum power consumption in milliwatts that the
 551  * cooling device can currently consume and store it in @min_power.
 552  *
 553  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 554  * power_actor API or -E* on other error.
 555  */
 556 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
 557                               struct thermal_zone_device *tz, u32 *min_power)
 558 {
 559         unsigned long max_state;
 560         int ret;
 561
 562         if (!cdev_is_power_actor(cdev))
 563                 return -EINVAL;
 564
 565         ret = cdev->ops->get_max_state(cdev, &max_state);
 566         if (ret)
 567                 return ret;
 568
 569         return cdev->ops->state2power(cdev, tz, max_state, min_power);
 570 }
 571
 572 /**
 573  * power_actor_set_power() - limit the maximum power a cooling device consumes
 574  * @cdev:       pointer to &thermal_cooling_device
 575  * @instance:   thermal instance to update
 576  * @power:      the power in milliwatts
 577  *
 578  * Set the cooling device to consume at most @power milliwatts. The limit is
 579  * expected to be a cap at the maximum power consumption.
 580  *
 581  * Return: 0 on success, -EINVAL if the cooling device does not
 582  * implement the power actor API or -E* for other failures.
 583  */
 584 int power_actor_set_power(struct thermal_cooling_device *cdev,
 585                           struct thermal_instance *instance, u32 power)
 586 {
 587         unsigned long state;
 588         int ret;
 589
 590         if (!cdev_is_power_actor(cdev))
 591                 return -EINVAL;
 592
 593         ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
 594         if (ret)
 595                 return ret;
 596
 597         instance->target = state;
 598         mutex_lock(&cdev->lock);
 599         cdev->updated = false;
 600         mutex_unlock(&cdev->lock);
 601         thermal_cdev_update(cdev);
 602
 603         return 0;
 604 }
 605
 606 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
 607                                           const char *cdev_type, size_t size)
 608 {
 609         struct thermal_cooling_device *cdev = NULL;
 610
 611         mutex_lock(&thermal_list_lock);
 612         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 613                 /* skip non matching cdevs */
 614                 if (strncmp(cdev_type, cdev->type, size))
 615                         continue;
 616
 617                 /* re binding the exception matching the type pattern */
 618                 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
 619                                                  THERMAL_NO_LIMIT,
 620                                                  THERMAL_NO_LIMIT,
 621                                                  THERMAL_WEIGHT_DEFAULT);
 622         }
 623         mutex_unlock(&thermal_list_lock);
 624 }
 625
 626 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
 627                                           const char *cdev_type, size_t size)
 628 {
 629         struct thermal_cooling_device *cdev = NULL;
 630
 631         mutex_lock(&thermal_list_lock);
 632         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 633                 /* skip non matching cdevs */
 634                 if (strncmp(cdev_type, cdev->type, size))
 635                         continue;
 636                 /* unbinding the exception matching the type pattern */
 637                 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
 638                                                    cdev);
 639         }
 640         mutex_unlock(&thermal_list_lock);
 641 }
 642
 643 /*
 644  * Device management section: cooling devices, zones devices, and binding
 645  *
 646  * Set of functions provided by the thermal core for:
 647  * - cooling devices lifecycle: registration, unregistration,
 648  *                              binding, and unbinding.
 649  * - thermal zone devices lifecycle: registration, unregistration,
 650  *                                   binding, and unbinding.
 651  */
 652
 653 /**
 654  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 655  * @tz:         pointer to struct thermal_zone_device
 656  * @trip:       indicates which trip point the cooling devices is
 657  *              associated with in this thermal zone.
 658  * @cdev:       pointer to struct thermal_cooling_device
 659  * @upper:      the Maximum cooling state for this trip point.
 660  *              THERMAL_NO_LIMIT means no upper limit,
 661  *              and the cooling device can be in max_state.
 662  * @lower:      the Minimum cooling state can be used for this trip point.
 663  *              THERMAL_NO_LIMIT means no lower limit,
 664  *              and the cooling device can be in cooling state 0.
 665  * @weight:     The weight of the cooling device to be bound to the
 666  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 667  *              default value
 668  *
 669  * This interface function bind a thermal cooling device to the certain trip
 670  * point of a thermal zone device.
 671  * This function is usually called in the thermal zone device .bind callback.
 672  *
 673  * Return: 0 on success, the proper error value otherwise.
 674  */
 675 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 676                                      int trip,
 677                                      struct thermal_cooling_device *cdev,
 678                                      unsigned long upper, unsigned long lower,
 679                                      unsigned int weight)
 680 {
 681         struct thermal_instance *dev;
 682         struct thermal_instance *pos;
 683         struct thermal_zone_device *pos1;
 684         struct thermal_cooling_device *pos2;
 685         unsigned long max_state;
 686         int result, ret;
 687
 688         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 689                 return -EINVAL;
 690
 691         list_for_each_entry(pos1, &thermal_tz_list, node) {
 692                 if (pos1 == tz)
 693                         break;
 694         }
 695         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 696                 if (pos2 == cdev)
 697                         break;
 698         }
 699
 700         if (tz != pos1 || cdev != pos2)
 701                 return -EINVAL;
 702
 703         ret = cdev->ops->get_max_state(cdev, &max_state);
 704         if (ret)
 705                 return ret;
 706
 707         /* lower default 0, upper default max_state */
 708         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 709         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 710
 711         if (lower > upper || upper > max_state)
 712                 return -EINVAL;
 713
 714         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 715         if (!dev)
 716                 return -ENOMEM;
 717         dev->tz = tz;
 718         dev->cdev = cdev;
 719         dev->trip = trip;
 720         dev->upper = upper;
 721         dev->lower = lower;
 722         dev->target = THERMAL_NO_TARGET;
 723         dev->weight = weight;
 724
 725         result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
 726         if (result < 0)
 727                 goto free_mem;
 728
 729         dev->id = result;
 730         sprintf(dev->name, "cdev%d", dev->id);
 731         result =
 732             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 733         if (result)
 734                 goto release_ida;
 735
 736         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 737         sysfs_attr_init(&dev->attr.attr);
 738         dev->attr.attr.name = dev->attr_name;
 739         dev->attr.attr.mode = 0444;
 740         dev->attr.show = trip_point_show;
 741         result = device_create_file(&tz->device, &dev->attr);
 742         if (result)
 743                 goto remove_symbol_link;
 744
 745         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
 746         sysfs_attr_init(&dev->weight_attr.attr);
 747         dev->weight_attr.attr.name = dev->weight_attr_name;
 748         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 749         dev->weight_attr.show = weight_show;
 750         dev->weight_attr.store = weight_store;
 751         result = device_create_file(&tz->device, &dev->weight_attr);
 752         if (result)
 753                 goto remove_trip_file;
 754
 755         mutex_lock(&tz->lock);
 756         mutex_lock(&cdev->lock);
 757         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 758                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 759                         result = -EEXIST;
 760                         break;
 761                 }
 762         if (!result) {
 763                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 764                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 765                 atomic_set(&tz->need_update, 1);
 766         }
 767         mutex_unlock(&cdev->lock);
 768         mutex_unlock(&tz->lock);
 769
 770         if (!result)
 771                 return 0;
 772
 773         device_remove_file(&tz->device, &dev->weight_attr);
 774 remove_trip_file:
 775         device_remove_file(&tz->device, &dev->attr);
 776 remove_symbol_link:
 777         sysfs_remove_link(&tz->device.kobj, dev->name);
 778 release_ida:
 779         ida_simple_remove(&tz->ida, dev->id);
 780 free_mem:
 781         kfree(dev);
 782         return result;
 783 }
 784 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 785
 786 /**
 787  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 788  *                                        thermal zone.
 789  * @tz:         pointer to a struct thermal_zone_device.
 790  * @trip:       indicates which trip point the cooling devices is
 791  *              associated with in this thermal zone.
 792  * @cdev:       pointer to a struct thermal_cooling_device.
 793  *
 794  * This interface function unbind a thermal cooling device from the certain
 795  * trip point of a thermal zone device.
 796  * This function is usually called in the thermal zone device .unbind callback.
 797  *
 798  * Return: 0 on success, the proper error value otherwise.
 799  */
 800 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 801                                        int trip,
 802                                        struct thermal_cooling_device *cdev)
 803 {
 804         struct thermal_instance *pos, *next;
 805
 806         mutex_lock(&tz->lock);
 807         mutex_lock(&cdev->lock);
 808         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 809                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 810                         list_del(&pos->tz_node);
 811                         list_del(&pos->cdev_node);
 812                         mutex_unlock(&cdev->lock);
 813                         mutex_unlock(&tz->lock);
 814                         goto unbind;
 815                 }
 816         }
 817         mutex_unlock(&cdev->lock);
 818         mutex_unlock(&tz->lock);
 819
 820         return -ENODEV;
 821
 822 unbind:
 823         device_remove_file(&tz->device, &pos->weight_attr);
 824         device_remove_file(&tz->device, &pos->attr);
 825         sysfs_remove_link(&tz->device.kobj, pos->name);
 826         ida_simple_remove(&tz->ida, pos->id);
 827         kfree(pos);
 828         return 0;
 829 }
 830 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 831
 832 static void thermal_release(struct device *dev)
 833 {
 834         struct thermal_zone_device *tz;
 835         struct thermal_cooling_device *cdev;
 836
 837         if (!strncmp(dev_name(dev), "thermal_zone",
 838                      sizeof("thermal_zone") - 1)) {
 839                 tz = to_thermal_zone(dev);
 840                 thermal_zone_destroy_device_groups(tz);
 841                 kfree(tz);
 842         } else if (!strncmp(dev_name(dev), "cooling_device",
 843                             sizeof("cooling_device") - 1)) {
 844                 cdev = to_cooling_device(dev);
 845                 kfree(cdev);
 846         }
 847 }
 848
 849 static struct class thermal_class = {
 850         .name = "thermal",
 851         .dev_release = thermal_release,
 852 };
 853
 854 static inline
 855 void print_bind_err_msg(struct thermal_zone_device *tz,
 856                         struct thermal_cooling_device *cdev, int ret)
 857 {
 858         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 859                 tz->type, cdev->type, ret);
 860 }
 861
 862 static void __bind(struct thermal_zone_device *tz, int mask,
 863                    struct thermal_cooling_device *cdev,
 864                    unsigned long *limits,
 865                    unsigned int weight)
 866 {
 867         int i, ret;
 868
 869         for (i = 0; i < tz->trips; i++) {
 870                 if (mask & (1 << i)) {
 871                         unsigned long upper, lower;
 872
 873                         upper = THERMAL_NO_LIMIT;
 874                         lower = THERMAL_NO_LIMIT;
 875                         if (limits) {
 876                                 lower = limits[i * 2];
 877                                 upper = limits[i * 2 + 1];
 878                         }
 879                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 880                                                                upper, lower,
 881                                                                weight);
 882                         if (ret)
 883                                 print_bind_err_msg(tz, cdev, ret);
 884                 }
 885         }
 886 }
 887
 888 static void bind_cdev(struct thermal_cooling_device *cdev)
 889 {
 890         int i, ret;
 891         const struct thermal_zone_params *tzp;
 892         struct thermal_zone_device *pos = NULL;
 893
 894         mutex_lock(&thermal_list_lock);
 895
 896         list_for_each_entry(pos, &thermal_tz_list, node) {
 897                 if (!pos->tzp && !pos->ops->bind)
 898                         continue;
 899
 900                 if (pos->ops->bind) {
 901                         ret = pos->ops->bind(pos, cdev);
 902                         if (ret)
 903                                 print_bind_err_msg(pos, cdev, ret);
 904                         continue;
 905                 }
 906
 907                 tzp = pos->tzp;
 908                 if (!tzp || !tzp->tbp)
 909                         continue;
 910
 911                 for (i = 0; i < tzp->num_tbps; i++) {
 912                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 913                                 continue;
 914                         if (tzp->tbp[i].match(pos, cdev))
 915                                 continue;
 916                         tzp->tbp[i].cdev = cdev;
 917                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 918                                tzp->tbp[i].binding_limits,
 919                                tzp->tbp[i].weight);
 920                 }
 921         }
 922
 923         mutex_unlock(&thermal_list_lock);
 924 }
 925
 926 /**
 927  * __thermal_cooling_device_register() - register a new thermal cooling device
 928  * @np:         a pointer to a device tree node.
 929  * @type:       the thermal cooling device type.
 930  * @devdata:    device private data.
 931  * @ops:                standard thermal cooling devices callbacks.
 932  *
 933  * This interface function adds a new thermal cooling device (fan/processor/...)
 934  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 935  * to all the thermal zone devices registered at the same time.
 936  * It also gives the opportunity to link the cooling device to a device tree
 937  * node, so that it can be bound to a thermal zone created out of device tree.
 938  *
 939  * Return: a pointer to the created struct thermal_cooling_device or an
 940  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 941  */
 942 static struct thermal_cooling_device *
 943 __thermal_cooling_device_register(struct device_node *np,
 944                                   char *type, void *devdata,
 945                                   const struct thermal_cooling_device_ops *ops)
 946 {
 947         struct thermal_cooling_device *cdev;
 948         struct thermal_zone_device *pos = NULL;
 949         int result;
 950
 951         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
 952                 return ERR_PTR(-EINVAL);
 953
 954         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 955             !ops->set_cur_state)
 956                 return ERR_PTR(-EINVAL);
 957
 958         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 959         if (!cdev)
 960                 return ERR_PTR(-ENOMEM);
 961
 962         result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
 963         if (result < 0) {
 964                 kfree(cdev);
 965                 return ERR_PTR(result);
 966         }
 967
 968         cdev->id = result;
 969         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
 970         mutex_init(&cdev->lock);
 971         INIT_LIST_HEAD(&cdev->thermal_instances);
 972         cdev->np = np;
 973         cdev->ops = ops;
 974         cdev->updated = false;
 975         cdev->device.class = &thermal_class;
 976         cdev->devdata = devdata;
 977         thermal_cooling_device_setup_sysfs(cdev);
 978         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 979         result = device_register(&cdev->device);
 980         if (result) {
 981                 ida_simple_remove(&thermal_cdev_ida, cdev->id);
 982                 kfree(cdev);
 983                 return ERR_PTR(result);
 984         }
 985
 986         /* Add 'this' new cdev to the global cdev list */
 987         mutex_lock(&thermal_list_lock);
 988         list_add(&cdev->node, &thermal_cdev_list);
 989         mutex_unlock(&thermal_list_lock);
 990
 991         /* Update binding information for 'this' new cdev */
 992         bind_cdev(cdev);
 993
 994         mutex_lock(&thermal_list_lock);
 995         list_for_each_entry(pos, &thermal_tz_list, node)
 996                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
 997                         thermal_zone_device_update(pos,
 998                                                    THERMAL_EVENT_UNSPECIFIED);
 999         mutex_unlock(&thermal_list_lock);
1000
1001         return cdev;
1002 }
1003
1004 /**
1005  * thermal_cooling_device_register() - register a new thermal cooling device
1006  * @type:       the thermal cooling device type.
1007  * @devdata:    device private data.
1008  * @ops:                standard thermal cooling devices callbacks.
1009  *
1010  * This interface function adds a new thermal cooling device (fan/processor/...)
1011  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1012  * to all the thermal zone devices registered at the same time.
1013  *
1014  * Return: a pointer to the created struct thermal_cooling_device or an
1015  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1016  */
1017 struct thermal_cooling_device *
1018 thermal_cooling_device_register(char *type, void *devdata,
1019                                 const struct thermal_cooling_device_ops *ops)
1020 {
1021         return __thermal_cooling_device_register(NULL, type, devdata, ops);
1022 }
1023 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1024
1025 /**
1026  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1027  * @np:         a pointer to a device tree node.
1028  * @type:       the thermal cooling device type.
1029  * @devdata:    device private data.
1030  * @ops:                standard thermal cooling devices callbacks.
1031  *
1032  * This function will register a cooling device with device tree node reference.
1033  * This interface function adds a new thermal cooling device (fan/processor/...)
1034  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1035  * to all the thermal zone devices registered at the same time.
1036  *
1037  * Return: a pointer to the created struct thermal_cooling_device or an
1038  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1039  */
1040 struct thermal_cooling_device *
1041 thermal_of_cooling_device_register(struct device_node *np,
1042                                    char *type, void *devdata,
1043                                    const struct thermal_cooling_device_ops *ops)
1044 {
1045         return __thermal_cooling_device_register(np, type, devdata, ops);
1046 }
1047 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1048
1049 static void __unbind(struct thermal_zone_device *tz, int mask,
1050                      struct thermal_cooling_device *cdev)
1051 {
1052         int i;
1053
1054         for (i = 0; i < tz->trips; i++)
1055                 if (mask & (1 << i))
1056                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1057 }
1058
1059 /**
1060  * thermal_cooling_device_unregister - removes a thermal cooling device
1061  * @cdev:       the thermal cooling device to remove.
1062  *
1063  * thermal_cooling_device_unregister() must be called when a registered
1064  * thermal cooling device is no longer needed.
1065  */
1066 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1067 {
1068         int i;
1069         const struct thermal_zone_params *tzp;
1070         struct thermal_zone_device *tz;
1071         struct thermal_cooling_device *pos = NULL;
1072
1073         if (!cdev)
1074                 return;
1075
1076         mutex_lock(&thermal_list_lock);
1077         list_for_each_entry(pos, &thermal_cdev_list, node)
1078                 if (pos == cdev)
1079                         break;
1080         if (pos != cdev) {
1081                 /* thermal cooling device not found */
1082                 mutex_unlock(&thermal_list_lock);
1083                 return;
1084         }
1085         list_del(&cdev->node);
1086
1087         /* Unbind all thermal zones associated with 'this' cdev */
1088         list_for_each_entry(tz, &thermal_tz_list, node) {
1089                 if (tz->ops->unbind) {
1090                         tz->ops->unbind(tz, cdev);
1091                         continue;
1092                 }
1093
1094                 if (!tz->tzp || !tz->tzp->tbp)
1095                         continue;
1096
1097                 tzp = tz->tzp;
1098                 for (i = 0; i < tzp->num_tbps; i++) {
1099                         if (tzp->tbp[i].cdev == cdev) {
1100                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1101                                 tzp->tbp[i].cdev = NULL;
1102                         }
1103                 }
1104         }
1105
1106         mutex_unlock(&thermal_list_lock);
1107
1108         ida_simple_remove(&thermal_cdev_ida, cdev->id);
1109         device_del(&cdev->device);
1110         thermal_cooling_device_destroy_sysfs(cdev);
1111         put_device(&cdev->device);
1112 }
1113 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1114
1115 static void bind_tz(struct thermal_zone_device *tz)
1116 {
1117         int i, ret;
1118         struct thermal_cooling_device *pos = NULL;
1119         const struct thermal_zone_params *tzp = tz->tzp;
1120
1121         if (!tzp && !tz->ops->bind)
1122                 return;
1123
1124         mutex_lock(&thermal_list_lock);
1125
1126         /* If there is ops->bind, try to use ops->bind */
1127         if (tz->ops->bind) {
1128                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1129                         ret = tz->ops->bind(tz, pos);
1130                         if (ret)
1131                                 print_bind_err_msg(tz, pos, ret);
1132                 }
1133                 goto exit;
1134         }
1135
1136         if (!tzp || !tzp->tbp)
1137                 goto exit;
1138
1139         list_for_each_entry(pos, &thermal_cdev_list, node) {
1140                 for (i = 0; i < tzp->num_tbps; i++) {
1141                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1142                                 continue;
1143                         if (tzp->tbp[i].match(tz, pos))
1144                                 continue;
1145                         tzp->tbp[i].cdev = pos;
1146                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1147                                tzp->tbp[i].binding_limits,
1148                                tzp->tbp[i].weight);
1149                 }
1150         }
1151 exit:
1152         mutex_unlock(&thermal_list_lock);
1153 }
1154
1155 /**
1156  * thermal_zone_device_register() - register a new thermal zone device
1157  * @type:       the thermal zone device type
1158  * @trips:      the number of trip points the thermal zone support
1159  * @mask:       a bit string indicating the writeablility of trip points
1160  * @devdata:    private device data
1161  * @ops:        standard thermal zone device callbacks
1162  * @tzp:        thermal zone platform parameters
1163  * @passive_delay: number of milliseconds to wait between polls when
1164  *                 performing passive cooling
1165  * @polling_delay: number of milliseconds to wait between polls when checking
1166  *                 whether trip points have been crossed (0 for interrupt
1167  *                 driven systems)
1168  *
1169  * This interface function adds a new thermal zone device (sensor) to
1170  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1171  * thermal cooling devices registered at the same time.
1172  * thermal_zone_device_unregister() must be called when the device is no
1173  * longer needed. The passive cooling depends on the .get_trend() return value.
1174  *
1175  * Return: a pointer to the created struct thermal_zone_device or an
1176  * in case of error, an ERR_PTR. Caller must check return value with
1177  * IS_ERR*() helpers.
1178  */
1179 struct thermal_zone_device *
1180 thermal_zone_device_register(const char *type, int trips, int mask,
1181                              void *devdata, struct thermal_zone_device_ops *ops,
1182                              struct thermal_zone_params *tzp, int passive_delay,
1183                              int polling_delay)
1184 {
1185         struct thermal_zone_device *tz;
1186         enum thermal_trip_type trip_type;
1187         int trip_temp;
1188         int result;
1189         int count;
1190         struct thermal_governor *governor;
1191
1192         if (!type || strlen(type) == 0)
1193                 return ERR_PTR(-EINVAL);
1194
1195         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1196                 return ERR_PTR(-EINVAL);
1197
1198         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
1199                 return ERR_PTR(-EINVAL);
1200
1201         if (!ops)
1202                 return ERR_PTR(-EINVAL);
1203
1204         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1205                 return ERR_PTR(-EINVAL);
1206
1207         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1208         if (!tz)
1209                 return ERR_PTR(-ENOMEM);
1210
1211         INIT_LIST_HEAD(&tz->thermal_instances);
1212         ida_init(&tz->ida);
1213         mutex_init(&tz->lock);
1214         result = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1215         if (result < 0)
1216                 goto free_tz;
1217
1218         tz->id = result;
1219         strlcpy(tz->type, type, sizeof(tz->type));
1220         tz->ops = ops;
1221         tz->tzp = tzp;
1222         tz->device.class = &thermal_class;
1223         tz->devdata = devdata;
1224         tz->trips = trips;
1225         tz->passive_delay = passive_delay;
1226         tz->polling_delay = polling_delay;
1227
1228         /* sys I/F */
1229         /* Add nodes that are always present via .groups */
1230         result = thermal_zone_create_device_groups(tz, mask);
1231         if (result)
1232                 goto remove_id;
1233
1234         /* A new thermal zone needs to be updated anyway. */
1235         atomic_set(&tz->need_update, 1);
1236
1237         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1238         result = device_register(&tz->device);
1239         if (result)
1240                 goto remove_device_groups;
1241
1242         for (count = 0; count < trips; count++) {
1243                 if (tz->ops->get_trip_type(tz, count, &trip_type))
1244                         set_bit(count, &tz->trips_disabled);
1245                 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1246                         set_bit(count, &tz->trips_disabled);
1247                 /* Check for bogus trip points */
1248                 if (trip_temp == 0)
1249                         set_bit(count, &tz->trips_disabled);
1250         }
1251
1252         /* Update 'this' zone's governor information */
1253         mutex_lock(&thermal_governor_lock);
1254
1255         if (tz->tzp)
1256                 governor = __find_governor(tz->tzp->governor_name);
1257         else
1258                 governor = def_governor;
1259
1260         result = thermal_set_governor(tz, governor);
1261         if (result) {
1262                 mutex_unlock(&thermal_governor_lock);
1263                 goto unregister;
1264         }
1265
1266         mutex_unlock(&thermal_governor_lock);
1267
1268         if (!tz->tzp || !tz->tzp->no_hwmon) {
1269                 result = thermal_add_hwmon_sysfs(tz);
1270                 if (result)
1271                         goto unregister;
1272         }
1273
1274         mutex_lock(&thermal_list_lock);
1275         list_add_tail(&tz->node, &thermal_tz_list);
1276         mutex_unlock(&thermal_list_lock);
1277
1278         /* Bind cooling devices for this zone */
1279         bind_tz(tz);
1280
1281         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1282
1283         thermal_zone_device_reset(tz);
1284         /* Update the new thermal zone and mark it as already updated. */
1285         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1286                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1287
1288         return tz;
1289
1290 unregister:
1291         ida_simple_remove(&thermal_tz_ida, tz->id);
1292         device_unregister(&tz->device);
1293         return ERR_PTR(result);
1294
1295 remove_device_groups:
1296         thermal_zone_destroy_device_groups(tz);
1297 remove_id:
1298         ida_simple_remove(&thermal_tz_ida, tz->id);
1299 free_tz:
1300         kfree(tz);
1301         return ERR_PTR(result);
1302 }
1303 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1304
1305 /**
1306  * thermal_device_unregister - removes the registered thermal zone device
1307  * @tz: the thermal zone device to remove
1308  */
1309 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1310 {
1311         int i;
1312         const struct thermal_zone_params *tzp;
1313         struct thermal_cooling_device *cdev;
1314         struct thermal_zone_device *pos = NULL;
1315
1316         if (!tz)
1317                 return;
1318
1319         tzp = tz->tzp;
1320
1321         mutex_lock(&thermal_list_lock);
1322         list_for_each_entry(pos, &thermal_tz_list, node)
1323                 if (pos == tz)
1324                         break;
1325         if (pos != tz) {
1326                 /* thermal zone device not found */
1327                 mutex_unlock(&thermal_list_lock);
1328                 return;
1329         }
1330         list_del(&tz->node);
1331
1332         /* Unbind all cdevs associated with 'this' thermal zone */
1333         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1334                 if (tz->ops->unbind) {
1335                         tz->ops->unbind(tz, cdev);
1336                         continue;
1337                 }
1338
1339                 if (!tzp || !tzp->tbp)
1340                         break;
1341
1342                 for (i = 0; i < tzp->num_tbps; i++) {
1343                         if (tzp->tbp[i].cdev == cdev) {
1344                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1345                                 tzp->tbp[i].cdev = NULL;
1346                         }
1347                 }
1348         }
1349
1350         mutex_unlock(&thermal_list_lock);
1351
1352         thermal_zone_device_set_polling(tz, 0);
1353
1354         thermal_set_governor(tz, NULL);
1355
1356         thermal_remove_hwmon_sysfs(tz);
1357         ida_simple_remove(&thermal_tz_ida, tz->id);
1358         ida_destroy(&tz->ida);
1359         mutex_destroy(&tz->lock);
1360         device_unregister(&tz->device);
1361 }
1362 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1363
1364 /**
1365  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1366  * @name: thermal zone name to fetch the temperature
1367  *
1368  * When only one zone is found with the passed name, returns a reference to it.
1369  *
1370  * Return: On success returns a reference to an unique thermal zone with
1371  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1372  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1373  */
1374 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1375 {
1376         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1377         unsigned int found = 0;
1378
1379         if (!name)
1380                 goto exit;
1381
1382         mutex_lock(&thermal_list_lock);
1383         list_for_each_entry(pos, &thermal_tz_list, node)
1384                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1385                         found++;
1386                         ref = pos;
1387                 }
1388         mutex_unlock(&thermal_list_lock);
1389
1390         /* nothing has been found, thus an error code for it */
1391         if (found == 0)
1392                 ref = ERR_PTR(-ENODEV);
1393         else if (found > 1)
1394         /* Success only when an unique zone is found */
1395                 ref = ERR_PTR(-EEXIST);
1396
1397 exit:
1398         return ref;
1399 }
1400 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1401
1402 #ifdef CONFIG_NET
1403 static const struct genl_multicast_group thermal_event_mcgrps[] = {
1404         { .name = THERMAL_GENL_MCAST_GROUP_NAME, },
1405 };
1406
1407 static struct genl_family thermal_event_genl_family __ro_after_init = {
1408         .module = THIS_MODULE,
1409         .name = THERMAL_GENL_FAMILY_NAME,
1410         .version = THERMAL_GENL_VERSION,
1411         .maxattr = THERMAL_GENL_ATTR_MAX,
1412         .mcgrps = thermal_event_mcgrps,
1413         .n_mcgrps = ARRAY_SIZE(thermal_event_mcgrps),
1414 };
1415
1416 int thermal_generate_netlink_event(struct thermal_zone_device *tz,
1417                                    enum events event)
1418 {
1419         struct sk_buff *skb;
1420         struct nlattr *attr;
1421         struct thermal_genl_event *thermal_event;
1422         void *msg_header;
1423         int size;
1424         int result;
1425         static unsigned int thermal_event_seqnum;
1426
1427         if (!tz)
1428                 return -EINVAL;
1429
1430         /* allocate memory */
1431         size = nla_total_size(sizeof(struct thermal_genl_event)) +
1432                nla_total_size(0);
1433
1434         skb = genlmsg_new(size, GFP_ATOMIC);
1435         if (!skb)
1436                 return -ENOMEM;
1437
1438         /* add the genetlink message header */
1439         msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++,
1440                                  &thermal_event_genl_family, 0,
1441                                  THERMAL_GENL_CMD_EVENT);
1442         if (!msg_header) {
1443                 nlmsg_free(skb);
1444                 return -ENOMEM;
1445         }
1446
1447         /* fill the data */
1448         attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT,
1449                            sizeof(struct thermal_genl_event));
1450
1451         if (!attr) {
1452                 nlmsg_free(skb);
1453                 return -EINVAL;
1454         }
1455
1456         thermal_event = nla_data(attr);
1457         if (!thermal_event) {
1458                 nlmsg_free(skb);
1459                 return -EINVAL;
1460         }
1461
1462         memset(thermal_event, 0, sizeof(struct thermal_genl_event));
1463
1464         thermal_event->orig = tz->id;
1465         thermal_event->event = event;
1466
1467         /* send multicast genetlink message */
1468         genlmsg_end(skb, msg_header);
1469
1470         result = genlmsg_multicast(&thermal_event_genl_family, skb, 0,
1471                                    0, GFP_ATOMIC);
1472         if (result)
1473                 dev_err(&tz->device, "Failed to send netlink event:%d", result);
1474
1475         return result;
1476 }
1477 EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
1478
1479 static int __init genetlink_init(void)
1480 {
1481         return genl_register_family(&thermal_event_genl_family);
1482 }
1483
1484 static void genetlink_exit(void)
1485 {
1486         genl_unregister_family(&thermal_event_genl_family);
1487 }
1488 #else /* !CONFIG_NET */
1489 static inline int genetlink_init(void) { return 0; }
1490 static inline void genetlink_exit(void) {}
1491 #endif /* !CONFIG_NET */
1492
1493 static int thermal_pm_notify(struct notifier_block *nb,
1494                              unsigned long mode, void *_unused)
1495 {
1496         struct thermal_zone_device *tz;
1497
1498         switch (mode) {
1499         case PM_HIBERNATION_PREPARE:
1500         case PM_RESTORE_PREPARE:
1501         case PM_SUSPEND_PREPARE:
1502                 atomic_set(&in_suspend, 1);
1503                 break;
1504         case PM_POST_HIBERNATION:
1505         case PM_POST_RESTORE:
1506         case PM_POST_SUSPEND:
1507                 atomic_set(&in_suspend, 0);
1508                 list_for_each_entry(tz, &thermal_tz_list, node) {
1509                         thermal_zone_device_init(tz);
1510                         thermal_zone_device_update(tz,
1511                                                    THERMAL_EVENT_UNSPECIFIED);
1512                 }
1513                 break;
1514         default:
1515                 break;
1516         }
1517         return 0;
1518 }
1519
1520 static struct notifier_block thermal_pm_nb = {
1521         .notifier_call = thermal_pm_notify,
1522 };
1523
1524 static int __init thermal_init(void)
1525 {
1526         int result;
1527
1528         mutex_init(&poweroff_lock);
1529         result = thermal_register_governors();
1530         if (result)
1531                 goto error;
1532
1533         result = class_register(&thermal_class);
1534         if (result)
1535                 goto unregister_governors;
1536
1537         result = genetlink_init();
1538         if (result)
1539                 goto unregister_class;
1540
1541         result = of_parse_thermal_zones();
1542         if (result)
1543                 goto exit_netlink;
1544
1545         result = register_pm_notifier(&thermal_pm_nb);
1546         if (result)
1547                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1548                         result);
1549
1550         return 0;
1551
1552 exit_netlink:
1553         genetlink_exit();
1554 unregister_class:
1555         class_unregister(&thermal_class);
1556 unregister_governors:
1557         thermal_unregister_governors();
1558 error:
1559         ida_destroy(&thermal_tz_ida);
1560         ida_destroy(&thermal_cdev_ida);
1561         mutex_destroy(&thermal_list_lock);
1562         mutex_destroy(&thermal_governor_lock);
1563         mutex_destroy(&poweroff_lock);
1564         return result;
1565 }
1566
1567 static void __exit thermal_exit(void)
1568 {
1569         unregister_pm_notifier(&thermal_pm_nb);
1570         of_thermal_destroy_zones();
1571         genetlink_exit();
1572         class_unregister(&thermal_class);
1573         thermal_unregister_governors();
1574         ida_destroy(&thermal_tz_ida);
1575         ida_destroy(&thermal_cdev_ida);
1576         mutex_destroy(&thermal_list_lock);
1577         mutex_destroy(&thermal_governor_lock);
1578 }
1579
1580 fs_initcall(thermal_init);
1581 module_exit(thermal_exit);