drivers/thermal/thermal_core.c

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