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  *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; version 2 of the License.
  13  *
  14  *  This program is distributed in the hope that it will be useful, but
  15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  *  General Public License for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License along
  20  *  with this program; if not, write to the Free Software Foundation, Inc.,
  21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  22  *
  23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  24  */
  25
  26 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  27
  28 #include <linux/module.h>
  29 #include <linux/device.h>
  30 #include <linux/err.h>
  31 #include <linux/slab.h>
  32 #include <linux/kdev_t.h>
  33 #include <linux/idr.h>
  34 #include <linux/thermal.h>
  35 #include <linux/reboot.h>
  36 #include <linux/string.h>
  37 #include <linux/of.h>
  38 #include <net/netlink.h>
  39 #include <net/genetlink.h>
  40 #include <linux/suspend.h>
  41
  42 #define CREATE_TRACE_POINTS
  43 #include <trace/events/thermal.h>
  44
  45 #include "thermal_core.h"
  46 #include "thermal_hwmon.h"
  47
  48 MODULE_AUTHOR("Zhang Rui");
  49 MODULE_DESCRIPTION("Generic thermal management sysfs support");
  50 MODULE_LICENSE("GPL v2");
  51
  52 static DEFINE_IDR(thermal_tz_idr);
  53 static DEFINE_IDR(thermal_cdev_idr);
  54 static DEFINE_MUTEX(thermal_idr_lock);
  55
  56 static LIST_HEAD(thermal_tz_list);
  57 static LIST_HEAD(thermal_cdev_list);
  58 static LIST_HEAD(thermal_governor_list);
  59
  60 static DEFINE_MUTEX(thermal_list_lock);
  61 static DEFINE_MUTEX(thermal_governor_lock);
  62
  63 static atomic_t in_suspend;
  64
  65 static struct thermal_governor *def_governor;
  66
  67 static struct thermal_governor *__find_governor(const char *name)
  68 {
  69         struct thermal_governor *pos;
  70
  71         if (!name || !name[0])
  72                 return def_governor;
  73
  74         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  75                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  76                         return pos;
  77
  78         return NULL;
  79 }
  80
  81 /**
  82  * bind_previous_governor() - bind the previous governor of the thermal zone
  83  * @tz:         a valid pointer to a struct thermal_zone_device
  84  * @failed_gov_name:    the name of the governor that failed to register
  85  *
  86  * Register the previous governor of the thermal zone after a new
  87  * governor has failed to be bound.
  88  */
  89 static void bind_previous_governor(struct thermal_zone_device *tz,
  90                                    const char *failed_gov_name)
  91 {
  92         if (tz->governor && tz->governor->bind_to_tz) {
  93                 if (tz->governor->bind_to_tz(tz)) {
  94                         dev_err(&tz->device,
  95                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  96                                 failed_gov_name, tz->governor->name, tz->type);
  97                         tz->governor = NULL;
  98                 }
  99         }
 100 }
 101
 102 /**
 103  * thermal_set_governor() - Switch to another governor
 104  * @tz:         a valid pointer to a struct thermal_zone_device
 105  * @new_gov:    pointer to the new governor
 106  *
 107  * Change the governor of thermal zone @tz.
 108  *
 109  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
 110  */
 111 static int thermal_set_governor(struct thermal_zone_device *tz,
 112                                 struct thermal_governor *new_gov)
 113 {
 114         int ret = 0;
 115
 116         if (tz->governor && tz->governor->unbind_from_tz)
 117                 tz->governor->unbind_from_tz(tz);
 118
 119         if (new_gov && new_gov->bind_to_tz) {
 120                 ret = new_gov->bind_to_tz(tz);
 121                 if (ret) {
 122                         bind_previous_governor(tz, new_gov->name);
 123
 124                         return ret;
 125                 }
 126         }
 127
 128         tz->governor = new_gov;
 129
 130         return ret;
 131 }
 132
 133 int thermal_register_governor(struct thermal_governor *governor)
 134 {
 135         int err;
 136         const char *name;
 137         struct thermal_zone_device *pos;
 138
 139         if (!governor)
 140                 return -EINVAL;
 141
 142         mutex_lock(&thermal_governor_lock);
 143
 144         err = -EBUSY;
 145         if (__find_governor(governor->name) == NULL) {
 146                 err = 0;
 147                 list_add(&governor->governor_list, &thermal_governor_list);
 148                 if (!def_governor && !strncmp(governor->name,
 149                         DEFAULT_THERMAL_GOVERNOR, THERMAL_NAME_LENGTH))
 150                         def_governor = governor;
 151         }
 152
 153         mutex_lock(&thermal_list_lock);
 154
 155         list_for_each_entry(pos, &thermal_tz_list, node) {
 156                 /*
 157                  * only thermal zones with specified tz->tzp->governor_name
 158                  * may run with tz->govenor unset
 159                  */
 160                 if (pos->governor)
 161                         continue;
 162
 163                 name = pos->tzp->governor_name;
 164
 165                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 166                         int ret;
 167
 168                         ret = thermal_set_governor(pos, governor);
 169                         if (ret)
 170                                 dev_err(&pos->device,
 171                                         "Failed to set governor %s for thermal zone %s: %d\n",
 172                                         governor->name, pos->type, ret);
 173                 }
 174         }
 175
 176         mutex_unlock(&thermal_list_lock);
 177         mutex_unlock(&thermal_governor_lock);
 178
 179         return err;
 180 }
 181
 182 void thermal_unregister_governor(struct thermal_governor *governor)
 183 {
 184         struct thermal_zone_device *pos;
 185
 186         if (!governor)
 187                 return;
 188
 189         mutex_lock(&thermal_governor_lock);
 190
 191         if (__find_governor(governor->name) == NULL)
 192                 goto exit;
 193
 194         mutex_lock(&thermal_list_lock);
 195
 196         list_for_each_entry(pos, &thermal_tz_list, node) {
 197                 if (!strncasecmp(pos->governor->name, governor->name,
 198                                                 THERMAL_NAME_LENGTH))
 199                         thermal_set_governor(pos, NULL);
 200         }
 201
 202         mutex_unlock(&thermal_list_lock);
 203         list_del(&governor->governor_list);
 204 exit:
 205         mutex_unlock(&thermal_governor_lock);
 206         return;
 207 }
 208
 209 static int get_idr(struct idr *idr, struct mutex *lock, int *id)
 210 {
 211         int ret;
 212
 213         if (lock)
 214                 mutex_lock(lock);
 215         ret = idr_alloc(idr, NULL, 0, 0, GFP_KERNEL);
 216         if (lock)
 217                 mutex_unlock(lock);
 218         if (unlikely(ret < 0))
 219                 return ret;
 220         *id = ret;
 221         return 0;
 222 }
 223
 224 static void release_idr(struct idr *idr, struct mutex *lock, int id)
 225 {
 226         if (lock)
 227                 mutex_lock(lock);
 228         idr_remove(idr, id);
 229         if (lock)
 230                 mutex_unlock(lock);
 231 }
 232
 233 int get_tz_trend(struct thermal_zone_device *tz, int trip)
 234 {
 235         enum thermal_trend trend;
 236
 237         if (tz->emul_temperature || !tz->ops->get_trend ||
 238             tz->ops->get_trend(tz, trip, &trend)) {
 239                 if (tz->temperature > tz->last_temperature)
 240                         trend = THERMAL_TREND_RAISING;
 241                 else if (tz->temperature < tz->last_temperature)
 242                         trend = THERMAL_TREND_DROPPING;
 243                 else
 244                         trend = THERMAL_TREND_STABLE;
 245         }
 246
 247         return trend;
 248 }
 249 EXPORT_SYMBOL(get_tz_trend);
 250
 251 struct thermal_instance *get_thermal_instance(struct thermal_zone_device *tz,
 252                         struct thermal_cooling_device *cdev, int trip)
 253 {
 254         struct thermal_instance *pos = NULL;
 255         struct thermal_instance *target_instance = NULL;
 256
 257         mutex_lock(&tz->lock);
 258         mutex_lock(&cdev->lock);
 259
 260         list_for_each_entry(pos, &tz->thermal_instances, tz_node) {
 261                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 262                         target_instance = pos;
 263                         break;
 264                 }
 265         }
 266
 267         mutex_unlock(&cdev->lock);
 268         mutex_unlock(&tz->lock);
 269
 270         return target_instance;
 271 }
 272 EXPORT_SYMBOL(get_thermal_instance);
 273
 274 static void print_bind_err_msg(struct thermal_zone_device *tz,
 275                         struct thermal_cooling_device *cdev, int ret)
 276 {
 277         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 278                                 tz->type, cdev->type, ret);
 279 }
 280
 281 static void __bind(struct thermal_zone_device *tz, int mask,
 282                         struct thermal_cooling_device *cdev,
 283                         unsigned long *limits,
 284                         unsigned int weight)
 285 {
 286         int i, ret;
 287
 288         for (i = 0; i < tz->trips; i++) {
 289                 if (mask & (1 << i)) {
 290                         unsigned long upper, lower;
 291
 292                         upper = THERMAL_NO_LIMIT;
 293                         lower = THERMAL_NO_LIMIT;
 294                         if (limits) {
 295                                 lower = limits[i * 2];
 296                                 upper = limits[i * 2 + 1];
 297                         }
 298                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 299                                                                upper, lower,
 300                                                                weight);
 301                         if (ret)
 302                                 print_bind_err_msg(tz, cdev, ret);
 303                 }
 304         }
 305 }
 306
 307 static void __unbind(struct thermal_zone_device *tz, int mask,
 308                         struct thermal_cooling_device *cdev)
 309 {
 310         int i;
 311
 312         for (i = 0; i < tz->trips; i++)
 313                 if (mask & (1 << i))
 314                         thermal_zone_unbind_cooling_device(tz, i, cdev);
 315 }
 316
 317 static void bind_cdev(struct thermal_cooling_device *cdev)
 318 {
 319         int i, ret;
 320         const struct thermal_zone_params *tzp;
 321         struct thermal_zone_device *pos = NULL;
 322
 323         mutex_lock(&thermal_list_lock);
 324
 325         list_for_each_entry(pos, &thermal_tz_list, node) {
 326                 if (!pos->tzp && !pos->ops->bind)
 327                         continue;
 328
 329                 if (pos->ops->bind) {
 330                         ret = pos->ops->bind(pos, cdev);
 331                         if (ret)
 332                                 print_bind_err_msg(pos, cdev, ret);
 333                         continue;
 334                 }
 335
 336                 tzp = pos->tzp;
 337                 if (!tzp || !tzp->tbp)
 338                         continue;
 339
 340                 for (i = 0; i < tzp->num_tbps; i++) {
 341                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 342                                 continue;
 343                         if (tzp->tbp[i].match(pos, cdev))
 344                                 continue;
 345                         tzp->tbp[i].cdev = cdev;
 346                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 347                                tzp->tbp[i].binding_limits,
 348                                tzp->tbp[i].weight);
 349                 }
 350         }
 351
 352         mutex_unlock(&thermal_list_lock);
 353 }
 354
 355 static void bind_tz(struct thermal_zone_device *tz)
 356 {
 357         int i, ret;
 358         struct thermal_cooling_device *pos = NULL;
 359         const struct thermal_zone_params *tzp = tz->tzp;
 360
 361         if (!tzp && !tz->ops->bind)
 362                 return;
 363
 364         mutex_lock(&thermal_list_lock);
 365
 366         /* If there is ops->bind, try to use ops->bind */
 367         if (tz->ops->bind) {
 368                 list_for_each_entry(pos, &thermal_cdev_list, node) {
 369                         ret = tz->ops->bind(tz, pos);
 370                         if (ret)
 371                                 print_bind_err_msg(tz, pos, ret);
 372                 }
 373                 goto exit;
 374         }
 375
 376         if (!tzp || !tzp->tbp)
 377                 goto exit;
 378
 379         list_for_each_entry(pos, &thermal_cdev_list, node) {
 380                 for (i = 0; i < tzp->num_tbps; i++) {
 381                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 382                                 continue;
 383                         if (tzp->tbp[i].match(tz, pos))
 384                                 continue;
 385                         tzp->tbp[i].cdev = pos;
 386                         __bind(tz, tzp->tbp[i].trip_mask, pos,
 387                                tzp->tbp[i].binding_limits,
 388                                tzp->tbp[i].weight);
 389                 }
 390         }
 391 exit:
 392         mutex_unlock(&thermal_list_lock);
 393 }
 394
 395 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 396                                             int delay)
 397 {
 398         if (delay > 1000)
 399                 mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 400                                  round_jiffies(msecs_to_jiffies(delay)));
 401         else if (delay)
 402                 mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 403                                  msecs_to_jiffies(delay));
 404         else
 405                 cancel_delayed_work(&tz->poll_queue);
 406 }
 407
 408 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 409 {
 410         mutex_lock(&tz->lock);
 411
 412         if (tz->passive)
 413                 thermal_zone_device_set_polling(tz, tz->passive_delay);
 414         else if (tz->polling_delay)
 415                 thermal_zone_device_set_polling(tz, tz->polling_delay);
 416         else
 417                 thermal_zone_device_set_polling(tz, 0);
 418
 419         mutex_unlock(&tz->lock);
 420 }
 421
 422 static void handle_non_critical_trips(struct thermal_zone_device *tz,
 423                         int trip, enum thermal_trip_type trip_type)
 424 {
 425         tz->governor ? tz->governor->throttle(tz, trip) :
 426                        def_governor->throttle(tz, trip);
 427 }
 428
 429 static void handle_critical_trips(struct thermal_zone_device *tz,
 430                                 int trip, enum thermal_trip_type trip_type)
 431 {
 432         int trip_temp;
 433
 434         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 435
 436         /* If we have not crossed the trip_temp, we do not care. */
 437         if (trip_temp <= 0 || tz->temperature < trip_temp)
 438                 return;
 439
 440         trace_thermal_zone_trip(tz, trip, trip_type);
 441
 442         if (tz->ops->notify)
 443                 tz->ops->notify(tz, trip, trip_type);
 444
 445         if (trip_type == THERMAL_TRIP_CRITICAL) {
 446                 dev_emerg(&tz->device,
 447                           "critical temperature reached(%d C),shutting down\n",
 448                           tz->temperature / 1000);
 449                 orderly_poweroff(true);
 450         }
 451 }
 452
 453 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 454 {
 455         enum thermal_trip_type type;
 456
 457         /* Ignore disabled trip points */
 458         if (test_bit(trip, &tz->trips_disabled))
 459                 return;
 460
 461         tz->ops->get_trip_type(tz, trip, &type);
 462
 463         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 464                 handle_critical_trips(tz, trip, type);
 465         else
 466                 handle_non_critical_trips(tz, trip, type);
 467         /*
 468          * Alright, we handled this trip successfully.
 469          * So, start monitoring again.
 470          */
 471         monitor_thermal_zone(tz);
 472 }
 473
 474 /**
 475  * thermal_zone_get_temp() - returns the temperature of a thermal zone
 476  * @tz: a valid pointer to a struct thermal_zone_device
 477  * @temp: a valid pointer to where to store the resulting temperature.
 478  *
 479  * When a valid thermal zone reference is passed, it will fetch its
 480  * temperature and fill @temp.
 481  *
 482  * Return: On success returns 0, an error code otherwise
 483  */
 484 int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp)
 485 {
 486         int ret = -EINVAL;
 487         int count;
 488         int crit_temp = INT_MAX;
 489         enum thermal_trip_type type;
 490
 491         if (!tz || IS_ERR(tz) || !tz->ops->get_temp)
 492                 goto exit;
 493
 494         mutex_lock(&tz->lock);
 495
 496         ret = tz->ops->get_temp(tz, temp);
 497
 498         if (IS_ENABLED(CONFIG_THERMAL_EMULATION) && tz->emul_temperature) {
 499                 for (count = 0; count < tz->trips; count++) {
 500                         ret = tz->ops->get_trip_type(tz, count, &type);
 501                         if (!ret && type == THERMAL_TRIP_CRITICAL) {
 502                                 ret = tz->ops->get_trip_temp(tz, count,
 503                                                 &crit_temp);
 504                                 break;
 505                         }
 506                 }
 507
 508                 /*
 509                  * Only allow emulating a temperature when the real temperature
 510                  * is below the critical temperature so that the emulation code
 511                  * cannot hide critical conditions.
 512                  */
 513                 if (!ret && *temp < crit_temp)
 514                         *temp = tz->emul_temperature;
 515         }
 516
 517         mutex_unlock(&tz->lock);
 518 exit:
 519         return ret;
 520 }
 521 EXPORT_SYMBOL_GPL(thermal_zone_get_temp);
 522
 523 void thermal_zone_set_trips(struct thermal_zone_device *tz)
 524 {
 525         int low = -INT_MAX;
 526         int high = INT_MAX;
 527         int trip_temp, hysteresis;
 528         int i, ret;
 529
 530         mutex_lock(&tz->lock);
 531
 532         if (!tz->ops->set_trips || !tz->ops->get_trip_hyst)
 533                 goto exit;
 534
 535         for (i = 0; i < tz->trips; i++) {
 536                 int trip_low;
 537
 538                 tz->ops->get_trip_temp(tz, i, &trip_temp);
 539                 tz->ops->get_trip_hyst(tz, i, &hysteresis);
 540
 541                 trip_low = trip_temp - hysteresis;
 542
 543                 if (trip_low < tz->temperature && trip_low > low)
 544                         low = trip_low;
 545
 546                 if (trip_temp > tz->temperature && trip_temp < high)
 547                         high = trip_temp;
 548         }
 549
 550         /* No need to change trip points */
 551         if (tz->prev_low_trip == low && tz->prev_high_trip == high)
 552                 goto exit;
 553
 554         tz->prev_low_trip = low;
 555         tz->prev_high_trip = high;
 556
 557         dev_dbg(&tz->device,
 558                 "new temperature boundaries: %d < x < %d\n", low, high);
 559
 560         /*
 561          * Set a temperature window. When this window is left the driver
 562          * must inform the thermal core via thermal_zone_device_update.
 563          */
 564         ret = tz->ops->set_trips(tz, low, high);
 565         if (ret)
 566                 dev_err(&tz->device, "Failed to set trips: %d\n", ret);
 567
 568 exit:
 569         mutex_unlock(&tz->lock);
 570 }
 571 EXPORT_SYMBOL_GPL(thermal_zone_set_trips);
 572
 573 static void update_temperature(struct thermal_zone_device *tz)
 574 {
 575         int temp, ret;
 576
 577         ret = thermal_zone_get_temp(tz, &temp);
 578         if (ret) {
 579                 if (ret != -EAGAIN)
 580                         dev_warn(&tz->device,
 581                                  "failed to read out thermal zone (%d)\n",
 582                                  ret);
 583                 return;
 584         }
 585
 586         mutex_lock(&tz->lock);
 587         tz->last_temperature = tz->temperature;
 588         tz->temperature = temp;
 589         mutex_unlock(&tz->lock);
 590
 591         trace_thermal_temperature(tz);
 592         if (tz->last_temperature == THERMAL_TEMP_INVALID)
 593                 dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n",
 594                         tz->temperature);
 595         else
 596                 dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
 597                         tz->last_temperature, tz->temperature);
 598 }
 599
 600 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
 601 {
 602         struct thermal_instance *pos;
 603
 604         tz->temperature = THERMAL_TEMP_INVALID;
 605         tz->passive = 0;
 606         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 607                 pos->initialized = false;
 608 }
 609
 610 void thermal_zone_device_update(struct thermal_zone_device *tz,
 611                                 enum thermal_notify_event event)
 612 {
 613         int count;
 614
 615         if (atomic_read(&in_suspend))
 616                 return;
 617
 618         if (!tz->ops->get_temp)
 619                 return;
 620
 621         update_temperature(tz);
 622
 623         thermal_zone_set_trips(tz);
 624
 625         tz->notify_event = event;
 626
 627         for (count = 0; count < tz->trips; count++)
 628                 handle_thermal_trip(tz, count);
 629 }
 630 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 631
 632 static void thermal_zone_device_check(struct work_struct *work)
 633 {
 634         struct thermal_zone_device *tz = container_of(work, struct
 635                                                       thermal_zone_device,
 636                                                       poll_queue.work);
 637         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 638 }
 639
 640 /**
 641  * power_actor_get_max_power() - get the maximum power that a cdev can consume
 642  * @cdev:       pointer to &thermal_cooling_device
 643  * @tz:         a valid thermal zone device pointer
 644  * @max_power:  pointer in which to store the maximum power
 645  *
 646  * Calculate the maximum power consumption in milliwats that the
 647  * cooling device can currently consume and store it in @max_power.
 648  *
 649  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 650  * power_actor API or -E* on other error.
 651  */
 652 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
 653                               struct thermal_zone_device *tz, u32 *max_power)
 654 {
 655         if (!cdev_is_power_actor(cdev))
 656                 return -EINVAL;
 657
 658         return cdev->ops->state2power(cdev, tz, 0, max_power);
 659 }
 660
 661 /**
 662  * power_actor_get_min_power() - get the mainimum power that a cdev can consume
 663  * @cdev:       pointer to &thermal_cooling_device
 664  * @tz:         a valid thermal zone device pointer
 665  * @min_power:  pointer in which to store the minimum power
 666  *
 667  * Calculate the minimum power consumption in milliwatts that the
 668  * cooling device can currently consume and store it in @min_power.
 669  *
 670  * Return: 0 on success, -EINVAL if @cdev doesn't support the
 671  * power_actor API or -E* on other error.
 672  */
 673 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
 674                               struct thermal_zone_device *tz, u32 *min_power)
 675 {
 676         unsigned long max_state;
 677         int ret;
 678
 679         if (!cdev_is_power_actor(cdev))
 680                 return -EINVAL;
 681
 682         ret = cdev->ops->get_max_state(cdev, &max_state);
 683         if (ret)
 684                 return ret;
 685
 686         return cdev->ops->state2power(cdev, tz, max_state, min_power);
 687 }
 688
 689 /**
 690  * power_actor_set_power() - limit the maximum power a cooling device consumes
 691  * @cdev:       pointer to &thermal_cooling_device
 692  * @instance:   thermal instance to update
 693  * @power:      the power in milliwatts
 694  *
 695  * Set the cooling device to consume at most @power milliwatts. The limit is
 696  * expected to be a cap at the maximum power consumption.
 697  *
 698  * Return: 0 on success, -EINVAL if the cooling device does not
 699  * implement the power actor API or -E* for other failures.
 700  */
 701 int power_actor_set_power(struct thermal_cooling_device *cdev,
 702                           struct thermal_instance *instance, u32 power)
 703 {
 704         unsigned long state;
 705         int ret;
 706
 707         if (!cdev_is_power_actor(cdev))
 708                 return -EINVAL;
 709
 710         ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
 711         if (ret)
 712                 return ret;
 713
 714         instance->target = state;
 715         mutex_lock(&cdev->lock);
 716         cdev->updated = false;
 717         mutex_unlock(&cdev->lock);
 718         thermal_cdev_update(cdev);
 719
 720         return 0;
 721 }
 722
 723 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
 724                                           const char *cdev_type, size_t size)
 725 {
 726         struct thermal_cooling_device *cdev = NULL;
 727
 728         mutex_lock(&thermal_list_lock);
 729         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 730                 /* skip non matching cdevs */
 731                 if (strncmp(cdev_type, cdev->type, size))
 732                         continue;
 733
 734                 /* re binding the exception matching the type pattern */
 735                 thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
 736                                                  THERMAL_NO_LIMIT,
 737                                                  THERMAL_NO_LIMIT,
 738                                                  THERMAL_WEIGHT_DEFAULT);
 739         }
 740         mutex_unlock(&thermal_list_lock);
 741 }
 742
 743 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
 744                                           const char *cdev_type, size_t size)
 745 {
 746         struct thermal_cooling_device *cdev = NULL;
 747
 748         mutex_lock(&thermal_list_lock);
 749         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 750                 /* skip non matching cdevs */
 751                 if (strncmp(cdev_type, cdev->type, size))
 752                         continue;
 753                 /* unbinding the exception matching the type pattern */
 754                 thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
 755                                                    cdev);
 756         }
 757         mutex_unlock(&thermal_list_lock);
 758 }
 759
 760 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 761                                    char *policy)
 762 {
 763         struct thermal_governor *gov;
 764         int ret = -EINVAL;
 765
 766         mutex_lock(&thermal_governor_lock);
 767         mutex_lock(&tz->lock);
 768
 769         gov = __find_governor(strim(policy));
 770         if (!gov)
 771                 goto exit;
 772
 773         ret = thermal_set_governor(tz, gov);
 774
 775 exit:
 776         mutex_unlock(&tz->lock);
 777         mutex_unlock(&thermal_governor_lock);
 778
 779         return ret;
 780 }
 781
 782 int thermal_build_list_of_policies(char *buf)
 783 {
 784         struct thermal_governor *pos;
 785         ssize_t count = 0;
 786         ssize_t size = PAGE_SIZE;
 787
 788         mutex_lock(&thermal_governor_lock);
 789
 790         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 791                 size = PAGE_SIZE - count;
 792                 count += scnprintf(buf + count, size, "%s ", pos->name);
 793         }
 794         count += scnprintf(buf + count, size, "\n");
 795
 796         mutex_unlock(&thermal_governor_lock);
 797
 798         return count;
 799 }
 800
 801 /* sys I/F for cooling device */
 802 #define to_cooling_device(_dev) \
 803         container_of(_dev, struct thermal_cooling_device, device)
 804
 805 static ssize_t
 806 thermal_cooling_device_type_show(struct device *dev,
 807                                  struct device_attribute *attr, char *buf)
 808 {
 809         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 810
 811         return sprintf(buf, "%s\n", cdev->type);
 812 }
 813
 814 static ssize_t
 815 thermal_cooling_device_max_state_show(struct device *dev,
 816                                       struct device_attribute *attr, char *buf)
 817 {
 818         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 819         unsigned long state;
 820         int ret;
 821
 822         ret = cdev->ops->get_max_state(cdev, &state);
 823         if (ret)
 824                 return ret;
 825         return sprintf(buf, "%ld\n", state);
 826 }
 827
 828 static ssize_t
 829 thermal_cooling_device_cur_state_show(struct device *dev,
 830                                       struct device_attribute *attr, char *buf)
 831 {
 832         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 833         unsigned long state;
 834         int ret;
 835
 836         ret = cdev->ops->get_cur_state(cdev, &state);
 837         if (ret)
 838                 return ret;
 839         return sprintf(buf, "%ld\n", state);
 840 }
 841
 842 static ssize_t
 843 thermal_cooling_device_cur_state_store(struct device *dev,
 844                                        struct device_attribute *attr,
 845                                        const char *buf, size_t count)
 846 {
 847         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 848         unsigned long state;
 849         int result;
 850
 851         if (sscanf(buf, "%ld\n", &state) != 1)
 852                 return -EINVAL;
 853
 854         if ((long)state < 0)
 855                 return -EINVAL;
 856
 857         result = cdev->ops->set_cur_state(cdev, state);
 858         if (result)
 859                 return result;
 860         return count;
 861 }
 862
 863 static struct device_attribute dev_attr_cdev_type =
 864 __ATTR(type, 0444, thermal_cooling_device_type_show, NULL);
 865 static DEVICE_ATTR(max_state, 0444,
 866                    thermal_cooling_device_max_state_show, NULL);
 867 static DEVICE_ATTR(cur_state, 0644,
 868                    thermal_cooling_device_cur_state_show,
 869                    thermal_cooling_device_cur_state_store);
 870
 871 static ssize_t
 872 thermal_cooling_device_trip_point_show(struct device *dev,
 873                                        struct device_attribute *attr, char *buf)
 874 {
 875         struct thermal_instance *instance;
 876
 877         instance =
 878             container_of(attr, struct thermal_instance, attr);
 879
 880         if (instance->trip == THERMAL_TRIPS_NONE)
 881                 return sprintf(buf, "-1\n");
 882         else
 883                 return sprintf(buf, "%d\n", instance->trip);
 884 }
 885
 886 static struct attribute *cooling_device_attrs[] = {
 887         &dev_attr_cdev_type.attr,
 888         &dev_attr_max_state.attr,
 889         &dev_attr_cur_state.attr,
 890         NULL,
 891 };
 892
 893 static const struct attribute_group cooling_device_attr_group = {
 894         .attrs = cooling_device_attrs,
 895 };
 896
 897 static const struct attribute_group *cooling_device_attr_groups[] = {
 898         &cooling_device_attr_group,
 899         NULL,
 900 };
 901
 902 static ssize_t
 903 thermal_cooling_device_weight_show(struct device *dev,
 904                                    struct device_attribute *attr, char *buf)
 905 {
 906         struct thermal_instance *instance;
 907
 908         instance = container_of(attr, struct thermal_instance, weight_attr);
 909
 910         return sprintf(buf, "%d\n", instance->weight);
 911 }
 912
 913 static ssize_t
 914 thermal_cooling_device_weight_store(struct device *dev,
 915                                     struct device_attribute *attr,
 916                                     const char *buf, size_t count)
 917 {
 918         struct thermal_instance *instance;
 919         int ret, weight;
 920
 921         ret = kstrtoint(buf, 0, &weight);
 922         if (ret)
 923                 return ret;
 924
 925         instance = container_of(attr, struct thermal_instance, weight_attr);
 926         instance->weight = weight;
 927
 928         return count;
 929 }
 930 /* Device management */
 931
 932 /**
 933  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 934  * @tz:         pointer to struct thermal_zone_device
 935  * @trip:       indicates which trip point the cooling devices is
 936  *              associated with in this thermal zone.
 937  * @cdev:       pointer to struct thermal_cooling_device
 938  * @upper:      the Maximum cooling state for this trip point.
 939  *              THERMAL_NO_LIMIT means no upper limit,
 940  *              and the cooling device can be in max_state.
 941  * @lower:      the Minimum cooling state can be used for this trip point.
 942  *              THERMAL_NO_LIMIT means no lower limit,
 943  *              and the cooling device can be in cooling state 0.
 944  * @weight:     The weight of the cooling device to be bound to the
 945  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 946  *              default value
 947  *
 948  * This interface function bind a thermal cooling device to the certain trip
 949  * point of a thermal zone device.
 950  * This function is usually called in the thermal zone device .bind callback.
 951  *
 952  * Return: 0 on success, the proper error value otherwise.
 953  */
 954 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 955                                      int trip,
 956                                      struct thermal_cooling_device *cdev,
 957                                      unsigned long upper, unsigned long lower,
 958                                      unsigned int weight)
 959 {
 960         struct thermal_instance *dev;
 961         struct thermal_instance *pos;
 962         struct thermal_zone_device *pos1;
 963         struct thermal_cooling_device *pos2;
 964         unsigned long max_state;
 965         int result, ret;
 966
 967         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 968                 return -EINVAL;
 969
 970         list_for_each_entry(pos1, &thermal_tz_list, node) {
 971                 if (pos1 == tz)
 972                         break;
 973         }
 974         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 975                 if (pos2 == cdev)
 976                         break;
 977         }
 978
 979         if (tz != pos1 || cdev != pos2)
 980                 return -EINVAL;
 981
 982         ret = cdev->ops->get_max_state(cdev, &max_state);
 983         if (ret)
 984                 return ret;
 985
 986         /* lower default 0, upper default max_state */
 987         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 988         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 989
 990         if (lower > upper || upper > max_state)
 991                 return -EINVAL;
 992
 993         dev =
 994             kzalloc(sizeof(struct thermal_instance), GFP_KERNEL);
 995         if (!dev)
 996                 return -ENOMEM;
 997         dev->tz = tz;
 998         dev->cdev = cdev;
 999         dev->trip = trip;
1000         dev->upper = upper;
1001         dev->lower = lower;
1002         dev->target = THERMAL_NO_TARGET;
1003         dev->weight = weight;
1004
1005         result = get_idr(&tz->idr, &tz->lock, &dev->id);
1006         if (result)
1007                 goto free_mem;
1008
1009         sprintf(dev->name, "cdev%d", dev->id);
1010         result =
1011             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
1012         if (result)
1013                 goto release_idr;
1014
1015         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
1016         sysfs_attr_init(&dev->attr.attr);
1017         dev->attr.attr.name = dev->attr_name;
1018         dev->attr.attr.mode = 0444;
1019         dev->attr.show = thermal_cooling_device_trip_point_show;
1020         result = device_create_file(&tz->device, &dev->attr);
1021         if (result)
1022                 goto remove_symbol_link;
1023
1024         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
1025         sysfs_attr_init(&dev->weight_attr.attr);
1026         dev->weight_attr.attr.name = dev->weight_attr_name;
1027         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
1028         dev->weight_attr.show = thermal_cooling_device_weight_show;
1029         dev->weight_attr.store = thermal_cooling_device_weight_store;
1030         result = device_create_file(&tz->device, &dev->weight_attr);
1031         if (result)
1032                 goto remove_trip_file;
1033
1034         mutex_lock(&tz->lock);
1035         mutex_lock(&cdev->lock);
1036         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
1037             if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
1038                 result = -EEXIST;
1039                 break;
1040         }
1041         if (!result) {
1042                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
1043                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
1044                 atomic_set(&tz->need_update, 1);
1045         }
1046         mutex_unlock(&cdev->lock);
1047         mutex_unlock(&tz->lock);
1048
1049         if (!result)
1050                 return 0;
1051
1052         device_remove_file(&tz->device, &dev->weight_attr);
1053 remove_trip_file:
1054         device_remove_file(&tz->device, &dev->attr);
1055 remove_symbol_link:
1056         sysfs_remove_link(&tz->device.kobj, dev->name);
1057 release_idr:
1058         release_idr(&tz->idr, &tz->lock, dev->id);
1059 free_mem:
1060         kfree(dev);
1061         return result;
1062 }
1063 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
1064
1065 /**
1066  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
1067  *                                        thermal zone.
1068  * @tz:         pointer to a struct thermal_zone_device.
1069  * @trip:       indicates which trip point the cooling devices is
1070  *              associated with in this thermal zone.
1071  * @cdev:       pointer to a struct thermal_cooling_device.
1072  *
1073  * This interface function unbind a thermal cooling device from the certain
1074  * trip point of a thermal zone device.
1075  * This function is usually called in the thermal zone device .unbind callback.
1076  *
1077  * Return: 0 on success, the proper error value otherwise.
1078  */
1079 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
1080                                        int trip,
1081                                        struct thermal_cooling_device *cdev)
1082 {
1083         struct thermal_instance *pos, *next;
1084
1085         mutex_lock(&tz->lock);
1086         mutex_lock(&cdev->lock);
1087         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
1088                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
1089                         list_del(&pos->tz_node);
1090                         list_del(&pos->cdev_node);
1091                         mutex_unlock(&cdev->lock);
1092                         mutex_unlock(&tz->lock);
1093                         goto unbind;
1094                 }
1095         }
1096         mutex_unlock(&cdev->lock);
1097         mutex_unlock(&tz->lock);
1098
1099         return -ENODEV;
1100
1101 unbind:
1102         device_remove_file(&tz->device, &pos->weight_attr);
1103         device_remove_file(&tz->device, &pos->attr);
1104         sysfs_remove_link(&tz->device.kobj, pos->name);
1105         release_idr(&tz->idr, &tz->lock, pos->id);
1106         kfree(pos);
1107         return 0;
1108 }
1109 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
1110
1111 static void thermal_release(struct device *dev)
1112 {
1113         struct thermal_zone_device *tz;
1114         struct thermal_cooling_device *cdev;
1115
1116         if (!strncmp(dev_name(dev), "thermal_zone",
1117                      sizeof("thermal_zone") - 1)) {
1118                 tz = to_thermal_zone(dev);
1119                 kfree(tz);
1120         } else if(!strncmp(dev_name(dev), "cooling_device",
1121                         sizeof("cooling_device") - 1)){
1122                 cdev = to_cooling_device(dev);
1123                 kfree(cdev);
1124         }
1125 }
1126
1127 static struct class thermal_class = {
1128         .name = "thermal",
1129         .dev_release = thermal_release,
1130 };
1131
1132 /**
1133  * __thermal_cooling_device_register() - register a new thermal cooling device
1134  * @np:         a pointer to a device tree node.
1135  * @type:       the thermal cooling device type.
1136  * @devdata:    device private data.
1137  * @ops:                standard thermal cooling devices callbacks.
1138  *
1139  * This interface function adds a new thermal cooling device (fan/processor/...)
1140  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1141  * to all the thermal zone devices registered at the same time.
1142  * It also gives the opportunity to link the cooling device to a device tree
1143  * node, so that it can be bound to a thermal zone created out of device tree.
1144  *
1145  * Return: a pointer to the created struct thermal_cooling_device or an
1146  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1147  */
1148 static struct thermal_cooling_device *
1149 __thermal_cooling_device_register(struct device_node *np,
1150                                   char *type, void *devdata,
1151                                   const struct thermal_cooling_device_ops *ops)
1152 {
1153         struct thermal_cooling_device *cdev;
1154         struct thermal_zone_device *pos = NULL;
1155         int result;
1156
1157         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1158                 return ERR_PTR(-EINVAL);
1159
1160         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1161             !ops->set_cur_state)
1162                 return ERR_PTR(-EINVAL);
1163
1164         cdev = kzalloc(sizeof(struct thermal_cooling_device), GFP_KERNEL);
1165         if (!cdev)
1166                 return ERR_PTR(-ENOMEM);
1167
1168         result = get_idr(&thermal_cdev_idr, &thermal_idr_lock, &cdev->id);
1169         if (result) {
1170                 kfree(cdev);
1171                 return ERR_PTR(result);
1172         }
1173
1174         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
1175         mutex_init(&cdev->lock);
1176         INIT_LIST_HEAD(&cdev->thermal_instances);
1177         cdev->np = np;
1178         cdev->ops = ops;
1179         cdev->updated = false;
1180         cdev->device.class = &thermal_class;
1181         cdev->device.groups = cooling_device_attr_groups;
1182         cdev->devdata = devdata;
1183         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1184         result = device_register(&cdev->device);
1185         if (result) {
1186                 release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
1187                 kfree(cdev);
1188                 return ERR_PTR(result);
1189         }
1190
1191         /* Add 'this' new cdev to the global cdev list */
1192         mutex_lock(&thermal_list_lock);
1193         list_add(&cdev->node, &thermal_cdev_list);
1194         mutex_unlock(&thermal_list_lock);
1195
1196         /* Update binding information for 'this' new cdev */
1197         bind_cdev(cdev);
1198
1199         mutex_lock(&thermal_list_lock);
1200         list_for_each_entry(pos, &thermal_tz_list, node)
1201                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
1202                         thermal_zone_device_update(pos,
1203                                                    THERMAL_EVENT_UNSPECIFIED);
1204         mutex_unlock(&thermal_list_lock);
1205
1206         return cdev;
1207 }
1208
1209 /**
1210  * thermal_cooling_device_register() - register a new thermal cooling device
1211  * @type:       the thermal cooling device type.
1212  * @devdata:    device private data.
1213  * @ops:                standard thermal cooling devices callbacks.
1214  *
1215  * This interface function adds a new thermal cooling device (fan/processor/...)
1216  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1217  * to all the thermal zone devices registered at the same time.
1218  *
1219  * Return: a pointer to the created struct thermal_cooling_device or an
1220  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1221  */
1222 struct thermal_cooling_device *
1223 thermal_cooling_device_register(char *type, void *devdata,
1224                                 const struct thermal_cooling_device_ops *ops)
1225 {
1226         return __thermal_cooling_device_register(NULL, type, devdata, ops);
1227 }
1228 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1229
1230 /**
1231  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1232  * @np:         a pointer to a device tree node.
1233  * @type:       the thermal cooling device type.
1234  * @devdata:    device private data.
1235  * @ops:                standard thermal cooling devices callbacks.
1236  *
1237  * This function will register a cooling device with device tree node reference.
1238  * This interface function adds a new thermal cooling device (fan/processor/...)
1239  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1240  * to all the thermal zone devices registered at the same time.
1241  *
1242  * Return: a pointer to the created struct thermal_cooling_device or an
1243  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1244  */
1245 struct thermal_cooling_device *
1246 thermal_of_cooling_device_register(struct device_node *np,
1247                                    char *type, void *devdata,
1248                                    const struct thermal_cooling_device_ops *ops)
1249 {
1250         return __thermal_cooling_device_register(np, type, devdata, ops);
1251 }
1252 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1253
1254 /**
1255  * thermal_cooling_device_unregister - removes the registered thermal cooling device
1256  * @cdev:       the thermal cooling device to remove.
1257  *
1258  * thermal_cooling_device_unregister() must be called when the device is no
1259  * longer needed.
1260  */
1261 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1262 {
1263         int i;
1264         const struct thermal_zone_params *tzp;
1265         struct thermal_zone_device *tz;
1266         struct thermal_cooling_device *pos = NULL;
1267
1268         if (!cdev)
1269                 return;
1270
1271         mutex_lock(&thermal_list_lock);
1272         list_for_each_entry(pos, &thermal_cdev_list, node)
1273             if (pos == cdev)
1274                 break;
1275         if (pos != cdev) {
1276                 /* thermal cooling device not found */
1277                 mutex_unlock(&thermal_list_lock);
1278                 return;
1279         }
1280         list_del(&cdev->node);
1281
1282         /* Unbind all thermal zones associated with 'this' cdev */
1283         list_for_each_entry(tz, &thermal_tz_list, node) {
1284                 if (tz->ops->unbind) {
1285                         tz->ops->unbind(tz, cdev);
1286                         continue;
1287                 }
1288
1289                 if (!tz->tzp || !tz->tzp->tbp)
1290                         continue;
1291
1292                 tzp = tz->tzp;
1293                 for (i = 0; i < tzp->num_tbps; i++) {
1294                         if (tzp->tbp[i].cdev == cdev) {
1295                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1296                                 tzp->tbp[i].cdev = NULL;
1297                         }
1298                 }
1299         }
1300
1301         mutex_unlock(&thermal_list_lock);
1302
1303         release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
1304         device_unregister(&cdev->device);
1305         return;
1306 }
1307 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1308
1309 void thermal_cdev_update(struct thermal_cooling_device *cdev)
1310 {
1311         struct thermal_instance *instance;
1312         unsigned long target = 0;
1313
1314         mutex_lock(&cdev->lock);
1315         /* cooling device is updated*/
1316         if (cdev->updated) {
1317                 mutex_unlock(&cdev->lock);
1318                 return;
1319         }
1320
1321         /* Make sure cdev enters the deepest cooling state */
1322         list_for_each_entry(instance, &cdev->thermal_instances, cdev_node) {
1323                 dev_dbg(&cdev->device, "zone%d->target=%lu\n",
1324                                 instance->tz->id, instance->target);
1325                 if (instance->target == THERMAL_NO_TARGET)
1326                         continue;
1327                 if (instance->target > target)
1328                         target = instance->target;
1329         }
1330         cdev->ops->set_cur_state(cdev, target);
1331         cdev->updated = true;
1332         mutex_unlock(&cdev->lock);
1333         trace_cdev_update(cdev, target);
1334         dev_dbg(&cdev->device, "set to state %lu\n", target);
1335 }
1336 EXPORT_SYMBOL(thermal_cdev_update);
1337
1338 /**
1339  * thermal_notify_framework - Sensor drivers use this API to notify framework
1340  * @tz:         thermal zone device
1341  * @trip:       indicates which trip point has been crossed
1342  *
1343  * This function handles the trip events from sensor drivers. It starts
1344  * throttling the cooling devices according to the policy configured.
1345  * For CRITICAL and HOT trip points, this notifies the respective drivers,
1346  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
1347  * The throttling policy is based on the configured platform data; if no
1348  * platform data is provided, this uses the step_wise throttling policy.
1349  */
1350 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
1351 {
1352         handle_thermal_trip(tz, trip);
1353 }
1354 EXPORT_SYMBOL_GPL(thermal_notify_framework);
1355
1356 /**
1357  * thermal_zone_device_register() - register a new thermal zone device
1358  * @type:       the thermal zone device type
1359  * @trips:      the number of trip points the thermal zone support
1360  * @mask:       a bit string indicating the writeablility of trip points
1361  * @devdata:    private device data
1362  * @ops:        standard thermal zone device callbacks
1363  * @tzp:        thermal zone platform parameters
1364  * @passive_delay: number of milliseconds to wait between polls when
1365  *                 performing passive cooling
1366  * @polling_delay: number of milliseconds to wait between polls when checking
1367  *                 whether trip points have been crossed (0 for interrupt
1368  *                 driven systems)
1369  *
1370  * This interface function adds a new thermal zone device (sensor) to
1371  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1372  * thermal cooling devices registered at the same time.
1373  * thermal_zone_device_unregister() must be called when the device is no
1374  * longer needed. The passive cooling depends on the .get_trend() return value.
1375  *
1376  * Return: a pointer to the created struct thermal_zone_device or an
1377  * in case of error, an ERR_PTR. Caller must check return value with
1378  * IS_ERR*() helpers.
1379  */
1380 struct thermal_zone_device *thermal_zone_device_register(const char *type,
1381         int trips, int mask, void *devdata,
1382         struct thermal_zone_device_ops *ops,
1383         struct thermal_zone_params *tzp,
1384         int passive_delay, int polling_delay)
1385 {
1386         struct thermal_zone_device *tz;
1387         enum thermal_trip_type trip_type;
1388         int trip_temp;
1389         int result;
1390         int count;
1391         struct thermal_governor *governor;
1392
1393         if (!type || strlen(type) == 0)
1394                 return ERR_PTR(-EINVAL);
1395
1396         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1397                 return ERR_PTR(-EINVAL);
1398
1399         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
1400                 return ERR_PTR(-EINVAL);
1401
1402         if (!ops)
1403                 return ERR_PTR(-EINVAL);
1404
1405         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1406                 return ERR_PTR(-EINVAL);
1407
1408         tz = kzalloc(sizeof(struct thermal_zone_device), GFP_KERNEL);
1409         if (!tz)
1410                 return ERR_PTR(-ENOMEM);
1411
1412         INIT_LIST_HEAD(&tz->thermal_instances);
1413         idr_init(&tz->idr);
1414         mutex_init(&tz->lock);
1415         result = get_idr(&thermal_tz_idr, &thermal_idr_lock, &tz->id);
1416         if (result) {
1417                 kfree(tz);
1418                 return ERR_PTR(result);
1419         }
1420
1421         strlcpy(tz->type, type, sizeof(tz->type));
1422         tz->ops = ops;
1423         tz->tzp = tzp;
1424         tz->device.class = &thermal_class;
1425         tz->devdata = devdata;
1426         tz->trips = trips;
1427         tz->passive_delay = passive_delay;
1428         tz->polling_delay = polling_delay;
1429
1430         /* sys I/F */
1431         /* Add nodes that are always present via .groups */
1432         result = thermal_zone_create_device_groups(tz, mask);
1433         if (result)
1434                 goto unregister;
1435
1436         /* A new thermal zone needs to be updated anyway. */
1437         atomic_set(&tz->need_update, 1);
1438
1439         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1440         result = device_register(&tz->device);
1441         if (result) {
1442                 release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1443                 kfree(tz);
1444                 return ERR_PTR(result);
1445         }
1446
1447         for (count = 0; count < trips; count++) {
1448                 if (tz->ops->get_trip_type(tz, count, &trip_type))
1449                         set_bit(count, &tz->trips_disabled);
1450                 if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1451                         set_bit(count, &tz->trips_disabled);
1452                 /* Check for bogus trip points */
1453                 if (trip_temp == 0)
1454                         set_bit(count, &tz->trips_disabled);
1455         }
1456
1457         /* Update 'this' zone's governor information */
1458         mutex_lock(&thermal_governor_lock);
1459
1460         if (tz->tzp)
1461                 governor = __find_governor(tz->tzp->governor_name);
1462         else
1463                 governor = def_governor;
1464
1465         result = thermal_set_governor(tz, governor);
1466         if (result) {
1467                 mutex_unlock(&thermal_governor_lock);
1468                 goto unregister;
1469         }
1470
1471         mutex_unlock(&thermal_governor_lock);
1472
1473         if (!tz->tzp || !tz->tzp->no_hwmon) {
1474                 result = thermal_add_hwmon_sysfs(tz);
1475                 if (result)
1476                         goto unregister;
1477         }
1478
1479         mutex_lock(&thermal_list_lock);
1480         list_add_tail(&tz->node, &thermal_tz_list);
1481         mutex_unlock(&thermal_list_lock);
1482
1483         /* Bind cooling devices for this zone */
1484         bind_tz(tz);
1485
1486         INIT_DELAYED_WORK(&(tz->poll_queue), thermal_zone_device_check);
1487
1488         thermal_zone_device_reset(tz);
1489         /* Update the new thermal zone and mark it as already updated. */
1490         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1491                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1492
1493         return tz;
1494
1495 unregister:
1496         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1497         device_unregister(&tz->device);
1498         return ERR_PTR(result);
1499 }
1500 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1501
1502 /**
1503  * thermal_device_unregister - removes the registered thermal zone device
1504  * @tz: the thermal zone device to remove
1505  */
1506 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1507 {
1508         int i;
1509         const struct thermal_zone_params *tzp;
1510         struct thermal_cooling_device *cdev;
1511         struct thermal_zone_device *pos = NULL;
1512
1513         if (!tz)
1514                 return;
1515
1516         tzp = tz->tzp;
1517
1518         mutex_lock(&thermal_list_lock);
1519         list_for_each_entry(pos, &thermal_tz_list, node)
1520             if (pos == tz)
1521                 break;
1522         if (pos != tz) {
1523                 /* thermal zone device not found */
1524                 mutex_unlock(&thermal_list_lock);
1525                 return;
1526         }
1527         list_del(&tz->node);
1528
1529         /* Unbind all cdevs associated with 'this' thermal zone */
1530         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1531                 if (tz->ops->unbind) {
1532                         tz->ops->unbind(tz, cdev);
1533                         continue;
1534                 }
1535
1536                 if (!tzp || !tzp->tbp)
1537                         break;
1538
1539                 for (i = 0; i < tzp->num_tbps; i++) {
1540                         if (tzp->tbp[i].cdev == cdev) {
1541                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1542                                 tzp->tbp[i].cdev = NULL;
1543                         }
1544                 }
1545         }
1546
1547         mutex_unlock(&thermal_list_lock);
1548
1549         thermal_zone_device_set_polling(tz, 0);
1550
1551         kfree(tz->trip_type_attrs);
1552         kfree(tz->trip_temp_attrs);
1553         kfree(tz->trip_hyst_attrs);
1554         kfree(tz->trips_attribute_group.attrs);
1555         thermal_set_governor(tz, NULL);
1556
1557         thermal_remove_hwmon_sysfs(tz);
1558         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1559         idr_destroy(&tz->idr);
1560         mutex_destroy(&tz->lock);
1561         device_unregister(&tz->device);
1562         kfree(tz->device.groups);
1563 }
1564 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1565
1566 /**
1567  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1568  * @name: thermal zone name to fetch the temperature
1569  *
1570  * When only one zone is found with the passed name, returns a reference to it.
1571  *
1572  * Return: On success returns a reference to an unique thermal zone with
1573  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1574  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1575  */
1576 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1577 {
1578         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1579         unsigned int found = 0;
1580
1581         if (!name)
1582                 goto exit;
1583
1584         mutex_lock(&thermal_list_lock);
1585         list_for_each_entry(pos, &thermal_tz_list, node)
1586                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1587                         found++;
1588                         ref = pos;
1589                 }
1590         mutex_unlock(&thermal_list_lock);
1591
1592         /* nothing has been found, thus an error code for it */
1593         if (found == 0)
1594                 ref = ERR_PTR(-ENODEV);
1595         else if (found > 1)
1596         /* Success only when an unique zone is found */
1597                 ref = ERR_PTR(-EEXIST);
1598
1599 exit:
1600         return ref;
1601 }
1602 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1603
1604 /**
1605  * thermal_zone_get_slope - return the slope attribute of the thermal zone
1606  * @tz: thermal zone device with the slope attribute
1607  *
1608  * Return: If the thermal zone device has a slope attribute, return it, else
1609  * return 1.
1610  */
1611 int thermal_zone_get_slope(struct thermal_zone_device *tz)
1612 {
1613         if (tz && tz->tzp)
1614                 return tz->tzp->slope;
1615         return 1;
1616 }
1617 EXPORT_SYMBOL_GPL(thermal_zone_get_slope);
1618
1619 /**
1620  * thermal_zone_get_offset - return the offset attribute of the thermal zone
1621  * @tz: thermal zone device with the offset attribute
1622  *
1623  * Return: If the thermal zone device has a offset attribute, return it, else
1624  * return 0.
1625  */
1626 int thermal_zone_get_offset(struct thermal_zone_device *tz)
1627 {
1628         if (tz && tz->tzp)
1629                 return tz->tzp->offset;
1630         return 0;
1631 }
1632 EXPORT_SYMBOL_GPL(thermal_zone_get_offset);
1633
1634 #ifdef CONFIG_NET
1635 static const struct genl_multicast_group thermal_event_mcgrps[] = {
1636         { .name = THERMAL_GENL_MCAST_GROUP_NAME, },
1637 };
1638
1639 static struct genl_family thermal_event_genl_family = {
1640         .id = GENL_ID_GENERATE,
1641         .name = THERMAL_GENL_FAMILY_NAME,
1642         .version = THERMAL_GENL_VERSION,
1643         .maxattr = THERMAL_GENL_ATTR_MAX,
1644         .mcgrps = thermal_event_mcgrps,
1645         .n_mcgrps = ARRAY_SIZE(thermal_event_mcgrps),
1646 };
1647
1648 int thermal_generate_netlink_event(struct thermal_zone_device *tz,
1649                                         enum events event)
1650 {
1651         struct sk_buff *skb;
1652         struct nlattr *attr;
1653         struct thermal_genl_event *thermal_event;
1654         void *msg_header;
1655         int size;
1656         int result;
1657         static unsigned int thermal_event_seqnum;
1658
1659         if (!tz)
1660                 return -EINVAL;
1661
1662         /* allocate memory */
1663         size = nla_total_size(sizeof(struct thermal_genl_event)) +
1664                nla_total_size(0);
1665
1666         skb = genlmsg_new(size, GFP_ATOMIC);
1667         if (!skb)
1668                 return -ENOMEM;
1669
1670         /* add the genetlink message header */
1671         msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++,
1672                                  &thermal_event_genl_family, 0,
1673                                  THERMAL_GENL_CMD_EVENT);
1674         if (!msg_header) {
1675                 nlmsg_free(skb);
1676                 return -ENOMEM;
1677         }
1678
1679         /* fill the data */
1680         attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT,
1681                            sizeof(struct thermal_genl_event));
1682
1683         if (!attr) {
1684                 nlmsg_free(skb);
1685                 return -EINVAL;
1686         }
1687
1688         thermal_event = nla_data(attr);
1689         if (!thermal_event) {
1690                 nlmsg_free(skb);
1691                 return -EINVAL;
1692         }
1693
1694         memset(thermal_event, 0, sizeof(struct thermal_genl_event));
1695
1696         thermal_event->orig = tz->id;
1697         thermal_event->event = event;
1698
1699         /* send multicast genetlink message */
1700         genlmsg_end(skb, msg_header);
1701
1702         result = genlmsg_multicast(&thermal_event_genl_family, skb, 0,
1703                                    0, GFP_ATOMIC);
1704         if (result)
1705                 dev_err(&tz->device, "Failed to send netlink event:%d", result);
1706
1707         return result;
1708 }
1709 EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
1710
1711 static int genetlink_init(void)
1712 {
1713         return genl_register_family(&thermal_event_genl_family);
1714 }
1715
1716 static void genetlink_exit(void)
1717 {
1718         genl_unregister_family(&thermal_event_genl_family);
1719 }
1720 #else /* !CONFIG_NET */
1721 static inline int genetlink_init(void) { return 0; }
1722 static inline void genetlink_exit(void) {}
1723 #endif /* !CONFIG_NET */
1724
1725 static int __init thermal_register_governors(void)
1726 {
1727         int result;
1728
1729         result = thermal_gov_step_wise_register();
1730         if (result)
1731                 return result;
1732
1733         result = thermal_gov_fair_share_register();
1734         if (result)
1735                 return result;
1736
1737         result = thermal_gov_bang_bang_register();
1738         if (result)
1739                 return result;
1740
1741         result = thermal_gov_user_space_register();
1742         if (result)
1743                 return result;
1744
1745         return thermal_gov_power_allocator_register();
1746 }
1747
1748 static void thermal_unregister_governors(void)
1749 {
1750         thermal_gov_step_wise_unregister();
1751         thermal_gov_fair_share_unregister();
1752         thermal_gov_bang_bang_unregister();
1753         thermal_gov_user_space_unregister();
1754         thermal_gov_power_allocator_unregister();
1755 }
1756
1757 static int thermal_pm_notify(struct notifier_block *nb,
1758                                 unsigned long mode, void *_unused)
1759 {
1760         struct thermal_zone_device *tz;
1761
1762         switch (mode) {
1763         case PM_HIBERNATION_PREPARE:
1764         case PM_RESTORE_PREPARE:
1765         case PM_SUSPEND_PREPARE:
1766                 atomic_set(&in_suspend, 1);
1767                 break;
1768         case PM_POST_HIBERNATION:
1769         case PM_POST_RESTORE:
1770         case PM_POST_SUSPEND:
1771                 atomic_set(&in_suspend, 0);
1772                 list_for_each_entry(tz, &thermal_tz_list, node) {
1773                         thermal_zone_device_reset(tz);
1774                         thermal_zone_device_update(tz,
1775                                                    THERMAL_EVENT_UNSPECIFIED);
1776                 }
1777                 break;
1778         default:
1779                 break;
1780         }
1781         return 0;
1782 }
1783
1784 static struct notifier_block thermal_pm_nb = {
1785         .notifier_call = thermal_pm_notify,
1786 };
1787
1788 static int __init thermal_init(void)
1789 {
1790         int result;
1791
1792         result = thermal_register_governors();
1793         if (result)
1794                 goto error;
1795
1796         result = class_register(&thermal_class);
1797         if (result)
1798                 goto unregister_governors;
1799
1800         result = genetlink_init();
1801         if (result)
1802                 goto unregister_class;
1803
1804         result = of_parse_thermal_zones();
1805         if (result)
1806                 goto exit_netlink;
1807
1808         result = register_pm_notifier(&thermal_pm_nb);
1809         if (result)
1810                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1811                         result);
1812
1813         return 0;
1814
1815 exit_netlink:
1816         genetlink_exit();
1817 unregister_class:
1818         class_unregister(&thermal_class);
1819 unregister_governors:
1820         thermal_unregister_governors();
1821 error:
1822         idr_destroy(&thermal_tz_idr);
1823         idr_destroy(&thermal_cdev_idr);
1824         mutex_destroy(&thermal_idr_lock);
1825         mutex_destroy(&thermal_list_lock);
1826         mutex_destroy(&thermal_governor_lock);
1827         return result;
1828 }
1829
1830 static void __exit thermal_exit(void)
1831 {
1832         unregister_pm_notifier(&thermal_pm_nb);
1833         of_thermal_destroy_zones();
1834         genetlink_exit();
1835         class_unregister(&thermal_class);
1836         thermal_unregister_governors();
1837         idr_destroy(&thermal_tz_idr);
1838         idr_destroy(&thermal_cdev_idr);
1839         mutex_destroy(&thermal_idr_lock);
1840         mutex_destroy(&thermal_list_lock);
1841         mutex_destroy(&thermal_governor_lock);
1842 }
1843
1844 fs_initcall(thermal_init);
1845 module_exit(thermal_exit);