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
  41 #define CREATE_TRACE_POINTS
  42 #include <trace/events/thermal.h>
  43
  44 #include "thermal_core.h"
  45 #include "thermal_hwmon.h"
  46
  47 MODULE_AUTHOR("Zhang Rui");
  48 MODULE_DESCRIPTION("Generic thermal management sysfs support");
  49 MODULE_LICENSE("GPL v2");
  50
  51 static DEFINE_IDR(thermal_tz_idr);
  52 static DEFINE_IDR(thermal_cdev_idr);
  53 static DEFINE_MUTEX(thermal_idr_lock);
  54
  55 static LIST_HEAD(thermal_tz_list);
  56 static LIST_HEAD(thermal_cdev_list);
  57 static LIST_HEAD(thermal_governor_list);
  58
  59 static DEFINE_MUTEX(thermal_list_lock);
  60 static DEFINE_MUTEX(thermal_governor_lock);
  61
  62 static struct thermal_governor *def_governor;
  63
  64 static struct thermal_governor *__find_governor(const char *name)
  65 {
  66         struct thermal_governor *pos;
  67
  68         if (!name || !name[0])
  69                 return def_governor;
  70
  71         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  72                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  73                         return pos;
  74
  75         return NULL;
  76 }
  77
  78 int thermal_register_governor(struct thermal_governor *governor)
  79 {
  80         int err;
  81         const char *name;
  82         struct thermal_zone_device *pos;
  83
  84         if (!governor)
  85                 return -EINVAL;
  86
  87         mutex_lock(&thermal_governor_lock);
  88
  89         err = -EBUSY;
  90         if (__find_governor(governor->name) == NULL) {
  91                 err = 0;
  92                 list_add(&governor->governor_list, &thermal_governor_list);
  93                 if (!def_governor && !strncmp(governor->name,
  94                         DEFAULT_THERMAL_GOVERNOR, THERMAL_NAME_LENGTH))
  95                         def_governor = governor;
  96         }
  97
  98         mutex_lock(&thermal_list_lock);
  99
 100         list_for_each_entry(pos, &thermal_tz_list, node) {
 101                 /*
 102                  * only thermal zones with specified tz->tzp->governor_name
 103                  * may run with tz->govenor unset
 104                  */
 105                 if (pos->governor)
 106                         continue;
 107
 108                 name = pos->tzp->governor_name;
 109
 110                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH))
 111                         pos->governor = governor;
 112         }
 113
 114         mutex_unlock(&thermal_list_lock);
 115         mutex_unlock(&thermal_governor_lock);
 116
 117         return err;
 118 }
 119
 120 void thermal_unregister_governor(struct thermal_governor *governor)
 121 {
 122         struct thermal_zone_device *pos;
 123
 124         if (!governor)
 125                 return;
 126
 127         mutex_lock(&thermal_governor_lock);
 128
 129         if (__find_governor(governor->name) == NULL)
 130                 goto exit;
 131
 132         mutex_lock(&thermal_list_lock);
 133
 134         list_for_each_entry(pos, &thermal_tz_list, node) {
 135                 if (!strncasecmp(pos->governor->name, governor->name,
 136                                                 THERMAL_NAME_LENGTH))
 137                         pos->governor = NULL;
 138         }
 139
 140         mutex_unlock(&thermal_list_lock);
 141         list_del(&governor->governor_list);
 142 exit:
 143         mutex_unlock(&thermal_governor_lock);
 144         return;
 145 }
 146
 147 static int get_idr(struct idr *idr, struct mutex *lock, int *id)
 148 {
 149         int ret;
 150
 151         if (lock)
 152                 mutex_lock(lock);
 153         ret = idr_alloc(idr, NULL, 0, 0, GFP_KERNEL);
 154         if (lock)
 155                 mutex_unlock(lock);
 156         if (unlikely(ret < 0))
 157                 return ret;
 158         *id = ret;
 159         return 0;
 160 }
 161
 162 static void release_idr(struct idr *idr, struct mutex *lock, int id)
 163 {
 164         if (lock)
 165                 mutex_lock(lock);
 166         idr_remove(idr, id);
 167         if (lock)
 168                 mutex_unlock(lock);
 169 }
 170
 171 int get_tz_trend(struct thermal_zone_device *tz, int trip)
 172 {
 173         enum thermal_trend trend;
 174
 175         if (tz->emul_temperature || !tz->ops->get_trend ||
 176             tz->ops->get_trend(tz, trip, &trend)) {
 177                 if (tz->temperature > tz->last_temperature)
 178                         trend = THERMAL_TREND_RAISING;
 179                 else if (tz->temperature < tz->last_temperature)
 180                         trend = THERMAL_TREND_DROPPING;
 181                 else
 182                         trend = THERMAL_TREND_STABLE;
 183         }
 184
 185         return trend;
 186 }
 187 EXPORT_SYMBOL(get_tz_trend);
 188
 189 struct thermal_instance *get_thermal_instance(struct thermal_zone_device *tz,
 190                         struct thermal_cooling_device *cdev, int trip)
 191 {
 192         struct thermal_instance *pos = NULL;
 193         struct thermal_instance *target_instance = NULL;
 194
 195         mutex_lock(&tz->lock);
 196         mutex_lock(&cdev->lock);
 197
 198         list_for_each_entry(pos, &tz->thermal_instances, tz_node) {
 199                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 200                         target_instance = pos;
 201                         break;
 202                 }
 203         }
 204
 205         mutex_unlock(&cdev->lock);
 206         mutex_unlock(&tz->lock);
 207
 208         return target_instance;
 209 }
 210 EXPORT_SYMBOL(get_thermal_instance);
 211
 212 static void print_bind_err_msg(struct thermal_zone_device *tz,
 213                         struct thermal_cooling_device *cdev, int ret)
 214 {
 215         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 216                                 tz->type, cdev->type, ret);
 217 }
 218
 219 static void __bind(struct thermal_zone_device *tz, int mask,
 220                         struct thermal_cooling_device *cdev,
 221                         unsigned long *limits)
 222 {
 223         int i, ret;
 224
 225         for (i = 0; i < tz->trips; i++) {
 226                 if (mask & (1 << i)) {
 227                         unsigned long upper, lower;
 228
 229                         upper = THERMAL_NO_LIMIT;
 230                         lower = THERMAL_NO_LIMIT;
 231                         if (limits) {
 232                                 lower = limits[i * 2];
 233                                 upper = limits[i * 2 + 1];
 234                         }
 235                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 236                                                                upper, lower);
 237                         if (ret)
 238                                 print_bind_err_msg(tz, cdev, ret);
 239                 }
 240         }
 241 }
 242
 243 static void __unbind(struct thermal_zone_device *tz, int mask,
 244                         struct thermal_cooling_device *cdev)
 245 {
 246         int i;
 247
 248         for (i = 0; i < tz->trips; i++)
 249                 if (mask & (1 << i))
 250                         thermal_zone_unbind_cooling_device(tz, i, cdev);
 251 }
 252
 253 static void bind_cdev(struct thermal_cooling_device *cdev)
 254 {
 255         int i, ret;
 256         const struct thermal_zone_params *tzp;
 257         struct thermal_zone_device *pos = NULL;
 258
 259         mutex_lock(&thermal_list_lock);
 260
 261         list_for_each_entry(pos, &thermal_tz_list, node) {
 262                 if (!pos->tzp && !pos->ops->bind)
 263                         continue;
 264
 265                 if (pos->ops->bind) {
 266                         ret = pos->ops->bind(pos, cdev);
 267                         if (ret)
 268                                 print_bind_err_msg(pos, cdev, ret);
 269                         continue;
 270                 }
 271
 272                 tzp = pos->tzp;
 273                 if (!tzp || !tzp->tbp)
 274                         continue;
 275
 276                 for (i = 0; i < tzp->num_tbps; i++) {
 277                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 278                                 continue;
 279                         if (tzp->tbp[i].match(pos, cdev))
 280                                 continue;
 281                         tzp->tbp[i].cdev = cdev;
 282                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
 283                                tzp->tbp[i].binding_limits);
 284                 }
 285         }
 286
 287         mutex_unlock(&thermal_list_lock);
 288 }
 289
 290 static void bind_tz(struct thermal_zone_device *tz)
 291 {
 292         int i, ret;
 293         struct thermal_cooling_device *pos = NULL;
 294         const struct thermal_zone_params *tzp = tz->tzp;
 295
 296         if (!tzp && !tz->ops->bind)
 297                 return;
 298
 299         mutex_lock(&thermal_list_lock);
 300
 301         /* If there is ops->bind, try to use ops->bind */
 302         if (tz->ops->bind) {
 303                 list_for_each_entry(pos, &thermal_cdev_list, node) {
 304                         ret = tz->ops->bind(tz, pos);
 305                         if (ret)
 306                                 print_bind_err_msg(tz, pos, ret);
 307                 }
 308                 goto exit;
 309         }
 310
 311         if (!tzp || !tzp->tbp)
 312                 goto exit;
 313
 314         list_for_each_entry(pos, &thermal_cdev_list, node) {
 315                 for (i = 0; i < tzp->num_tbps; i++) {
 316                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 317                                 continue;
 318                         if (tzp->tbp[i].match(tz, pos))
 319                                 continue;
 320                         tzp->tbp[i].cdev = pos;
 321                         __bind(tz, tzp->tbp[i].trip_mask, pos,
 322                                tzp->tbp[i].binding_limits);
 323                 }
 324         }
 325 exit:
 326         mutex_unlock(&thermal_list_lock);
 327 }
 328
 329 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 330                                             int delay)
 331 {
 332         if (delay > 1000)
 333                 mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 334                                  round_jiffies(msecs_to_jiffies(delay)));
 335         else if (delay)
 336                 mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 337                                  msecs_to_jiffies(delay));
 338         else
 339                 cancel_delayed_work(&tz->poll_queue);
 340 }
 341
 342 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 343 {
 344         mutex_lock(&tz->lock);
 345
 346         if (tz->passive)
 347                 thermal_zone_device_set_polling(tz, tz->passive_delay);
 348         else if (tz->polling_delay)
 349                 thermal_zone_device_set_polling(tz, tz->polling_delay);
 350         else
 351                 thermal_zone_device_set_polling(tz, 0);
 352
 353         mutex_unlock(&tz->lock);
 354 }
 355
 356 static void handle_non_critical_trips(struct thermal_zone_device *tz,
 357                         int trip, enum thermal_trip_type trip_type)
 358 {
 359         tz->governor ? tz->governor->throttle(tz, trip) :
 360                        def_governor->throttle(tz, trip);
 361 }
 362
 363 static void handle_critical_trips(struct thermal_zone_device *tz,
 364                                 int trip, enum thermal_trip_type trip_type)
 365 {
 366         long trip_temp;
 367
 368         tz->ops->get_trip_temp(tz, trip, &trip_temp);
 369
 370         /* If we have not crossed the trip_temp, we do not care. */
 371         if (trip_temp <= 0 || tz->temperature < trip_temp)
 372                 return;
 373
 374         trace_thermal_zone_trip(tz, trip, trip_type);
 375
 376         if (tz->ops->notify)
 377                 tz->ops->notify(tz, trip, trip_type);
 378
 379         if (trip_type == THERMAL_TRIP_CRITICAL) {
 380                 dev_emerg(&tz->device,
 381                           "critical temperature reached(%d C),shutting down\n",
 382                           tz->temperature / 1000);
 383                 orderly_poweroff(true);
 384         }
 385 }
 386
 387 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 388 {
 389         enum thermal_trip_type type;
 390
 391         tz->ops->get_trip_type(tz, trip, &type);
 392
 393         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 394                 handle_critical_trips(tz, trip, type);
 395         else
 396                 handle_non_critical_trips(tz, trip, type);
 397         /*
 398          * Alright, we handled this trip successfully.
 399          * So, start monitoring again.
 400          */
 401         monitor_thermal_zone(tz);
 402 }
 403
 404 /**
 405  * thermal_zone_get_temp() - returns its the temperature of thermal zone
 406  * @tz: a valid pointer to a struct thermal_zone_device
 407  * @temp: a valid pointer to where to store the resulting temperature.
 408  *
 409  * When a valid thermal zone reference is passed, it will fetch its
 410  * temperature and fill @temp.
 411  *
 412  * Return: On success returns 0, an error code otherwise
 413  */
 414 int thermal_zone_get_temp(struct thermal_zone_device *tz, unsigned long *temp)
 415 {
 416         int ret = -EINVAL;
 417 #ifdef CONFIG_THERMAL_EMULATION
 418         int count;
 419         unsigned long crit_temp = -1UL;
 420         enum thermal_trip_type type;
 421 #endif
 422
 423         if (!tz || IS_ERR(tz) || !tz->ops->get_temp)
 424                 goto exit;
 425
 426         mutex_lock(&tz->lock);
 427
 428         ret = tz->ops->get_temp(tz, temp);
 429 #ifdef CONFIG_THERMAL_EMULATION
 430         if (!tz->emul_temperature)
 431                 goto skip_emul;
 432
 433         for (count = 0; count < tz->trips; count++) {
 434                 ret = tz->ops->get_trip_type(tz, count, &type);
 435                 if (!ret && type == THERMAL_TRIP_CRITICAL) {
 436                         ret = tz->ops->get_trip_temp(tz, count, &crit_temp);
 437                         break;
 438                 }
 439         }
 440
 441         if (ret)
 442                 goto skip_emul;
 443
 444         if (*temp < crit_temp)
 445                 *temp = tz->emul_temperature;
 446 skip_emul:
 447 #endif
 448         mutex_unlock(&tz->lock);
 449 exit:
 450         return ret;
 451 }
 452 EXPORT_SYMBOL_GPL(thermal_zone_get_temp);
 453
 454 static void update_temperature(struct thermal_zone_device *tz)
 455 {
 456         long temp;
 457         int ret;
 458
 459         ret = thermal_zone_get_temp(tz, &temp);
 460         if (ret) {
 461                 dev_warn(&tz->device, "failed to read out thermal zone %d\n",
 462                          tz->id);
 463                 return;
 464         }
 465
 466         mutex_lock(&tz->lock);
 467         tz->last_temperature = tz->temperature;
 468         tz->temperature = temp;
 469         mutex_unlock(&tz->lock);
 470
 471         trace_thermal_temperature(tz);
 472         dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
 473                                 tz->last_temperature, tz->temperature);
 474 }
 475
 476 void thermal_zone_device_update(struct thermal_zone_device *tz)
 477 {
 478         int count;
 479
 480         if (!tz->ops->get_temp)
 481                 return;
 482
 483         update_temperature(tz);
 484
 485         for (count = 0; count < tz->trips; count++)
 486                 handle_thermal_trip(tz, count);
 487 }
 488 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 489
 490 static void thermal_zone_device_check(struct work_struct *work)
 491 {
 492         struct thermal_zone_device *tz = container_of(work, struct
 493                                                       thermal_zone_device,
 494                                                       poll_queue.work);
 495         thermal_zone_device_update(tz);
 496 }
 497
 498 /* sys I/F for thermal zone */
 499
 500 #define to_thermal_zone(_dev) \
 501         container_of(_dev, struct thermal_zone_device, device)
 502
 503 static ssize_t
 504 type_show(struct device *dev, struct device_attribute *attr, char *buf)
 505 {
 506         struct thermal_zone_device *tz = to_thermal_zone(dev);
 507
 508         return sprintf(buf, "%s\n", tz->type);
 509 }
 510
 511 static ssize_t
 512 temp_show(struct device *dev, struct device_attribute *attr, char *buf)
 513 {
 514         struct thermal_zone_device *tz = to_thermal_zone(dev);
 515         long temperature;
 516         int ret;
 517
 518         ret = thermal_zone_get_temp(tz, &temperature);
 519
 520         if (ret)
 521                 return ret;
 522
 523         return sprintf(buf, "%ld\n", temperature);
 524 }
 525
 526 static ssize_t
 527 mode_show(struct device *dev, struct device_attribute *attr, char *buf)
 528 {
 529         struct thermal_zone_device *tz = to_thermal_zone(dev);
 530         enum thermal_device_mode mode;
 531         int result;
 532
 533         if (!tz->ops->get_mode)
 534                 return -EPERM;
 535
 536         result = tz->ops->get_mode(tz, &mode);
 537         if (result)
 538                 return result;
 539
 540         return sprintf(buf, "%s\n", mode == THERMAL_DEVICE_ENABLED ? "enabled"
 541                        : "disabled");
 542 }
 543
 544 static ssize_t
 545 mode_store(struct device *dev, struct device_attribute *attr,
 546            const char *buf, size_t count)
 547 {
 548         struct thermal_zone_device *tz = to_thermal_zone(dev);
 549         int result;
 550
 551         if (!tz->ops->set_mode)
 552                 return -EPERM;
 553
 554         if (!strncmp(buf, "enabled", sizeof("enabled") - 1))
 555                 result = tz->ops->set_mode(tz, THERMAL_DEVICE_ENABLED);
 556         else if (!strncmp(buf, "disabled", sizeof("disabled") - 1))
 557                 result = tz->ops->set_mode(tz, THERMAL_DEVICE_DISABLED);
 558         else
 559                 result = -EINVAL;
 560
 561         if (result)
 562                 return result;
 563
 564         return count;
 565 }
 566
 567 static ssize_t
 568 trip_point_type_show(struct device *dev, struct device_attribute *attr,
 569                      char *buf)
 570 {
 571         struct thermal_zone_device *tz = to_thermal_zone(dev);
 572         enum thermal_trip_type type;
 573         int trip, result;
 574
 575         if (!tz->ops->get_trip_type)
 576                 return -EPERM;
 577
 578         if (!sscanf(attr->attr.name, "trip_point_%d_type", &trip))
 579                 return -EINVAL;
 580
 581         result = tz->ops->get_trip_type(tz, trip, &type);
 582         if (result)
 583                 return result;
 584
 585         switch (type) {
 586         case THERMAL_TRIP_CRITICAL:
 587                 return sprintf(buf, "critical\n");
 588         case THERMAL_TRIP_HOT:
 589                 return sprintf(buf, "hot\n");
 590         case THERMAL_TRIP_PASSIVE:
 591                 return sprintf(buf, "passive\n");
 592         case THERMAL_TRIP_ACTIVE:
 593                 return sprintf(buf, "active\n");
 594         default:
 595                 return sprintf(buf, "unknown\n");
 596         }
 597 }
 598
 599 static ssize_t
 600 trip_point_temp_store(struct device *dev, struct device_attribute *attr,
 601                      const char *buf, size_t count)
 602 {
 603         struct thermal_zone_device *tz = to_thermal_zone(dev);
 604         int trip, ret;
 605         unsigned long temperature;
 606
 607         if (!tz->ops->set_trip_temp)
 608                 return -EPERM;
 609
 610         if (!sscanf(attr->attr.name, "trip_point_%d_temp", &trip))
 611                 return -EINVAL;
 612
 613         if (kstrtoul(buf, 10, &temperature))
 614                 return -EINVAL;
 615
 616         ret = tz->ops->set_trip_temp(tz, trip, temperature);
 617
 618         return ret ? ret : count;
 619 }
 620
 621 static ssize_t
 622 trip_point_temp_show(struct device *dev, struct device_attribute *attr,
 623                      char *buf)
 624 {
 625         struct thermal_zone_device *tz = to_thermal_zone(dev);
 626         int trip, ret;
 627         long temperature;
 628
 629         if (!tz->ops->get_trip_temp)
 630                 return -EPERM;
 631
 632         if (!sscanf(attr->attr.name, "trip_point_%d_temp", &trip))
 633                 return -EINVAL;
 634
 635         ret = tz->ops->get_trip_temp(tz, trip, &temperature);
 636
 637         if (ret)
 638                 return ret;
 639
 640         return sprintf(buf, "%ld\n", temperature);
 641 }
 642
 643 static ssize_t
 644 trip_point_hyst_store(struct device *dev, struct device_attribute *attr,
 645                         const char *buf, size_t count)
 646 {
 647         struct thermal_zone_device *tz = to_thermal_zone(dev);
 648         int trip, ret;
 649         unsigned long temperature;
 650
 651         if (!tz->ops->set_trip_hyst)
 652                 return -EPERM;
 653
 654         if (!sscanf(attr->attr.name, "trip_point_%d_hyst", &trip))
 655                 return -EINVAL;
 656
 657         if (kstrtoul(buf, 10, &temperature))
 658                 return -EINVAL;
 659
 660         /*
 661          * We are not doing any check on the 'temperature' value
 662          * here. The driver implementing 'set_trip_hyst' has to
 663          * take care of this.
 664          */
 665         ret = tz->ops->set_trip_hyst(tz, trip, temperature);
 666
 667         return ret ? ret : count;
 668 }
 669
 670 static ssize_t
 671 trip_point_hyst_show(struct device *dev, struct device_attribute *attr,
 672                         char *buf)
 673 {
 674         struct thermal_zone_device *tz = to_thermal_zone(dev);
 675         int trip, ret;
 676         unsigned long temperature;
 677
 678         if (!tz->ops->get_trip_hyst)
 679                 return -EPERM;
 680
 681         if (!sscanf(attr->attr.name, "trip_point_%d_hyst", &trip))
 682                 return -EINVAL;
 683
 684         ret = tz->ops->get_trip_hyst(tz, trip, &temperature);
 685
 686         return ret ? ret : sprintf(buf, "%ld\n", temperature);
 687 }
 688
 689 static ssize_t
 690 passive_store(struct device *dev, struct device_attribute *attr,
 691                     const char *buf, size_t count)
 692 {
 693         struct thermal_zone_device *tz = to_thermal_zone(dev);
 694         struct thermal_cooling_device *cdev = NULL;
 695         int state;
 696
 697         if (!sscanf(buf, "%d\n", &state))
 698                 return -EINVAL;
 699
 700         /* sanity check: values below 1000 millicelcius don't make sense
 701          * and can cause the system to go into a thermal heart attack
 702          */
 703         if (state && state < 1000)
 704                 return -EINVAL;
 705
 706         if (state && !tz->forced_passive) {
 707                 mutex_lock(&thermal_list_lock);
 708                 list_for_each_entry(cdev, &thermal_cdev_list, node) {
 709                         if (!strncmp("Processor", cdev->type,
 710                                      sizeof("Processor")))
 711                                 thermal_zone_bind_cooling_device(tz,
 712                                                 THERMAL_TRIPS_NONE, cdev,
 713                                                 THERMAL_NO_LIMIT,
 714                                                 THERMAL_NO_LIMIT);
 715                 }
 716                 mutex_unlock(&thermal_list_lock);
 717                 if (!tz->passive_delay)
 718                         tz->passive_delay = 1000;
 719         } else if (!state && tz->forced_passive) {
 720                 mutex_lock(&thermal_list_lock);
 721                 list_for_each_entry(cdev, &thermal_cdev_list, node) {
 722                         if (!strncmp("Processor", cdev->type,
 723                                      sizeof("Processor")))
 724                                 thermal_zone_unbind_cooling_device(tz,
 725                                                                    THERMAL_TRIPS_NONE,
 726                                                                    cdev);
 727                 }
 728                 mutex_unlock(&thermal_list_lock);
 729                 tz->passive_delay = 0;
 730         }
 731
 732         tz->forced_passive = state;
 733
 734         thermal_zone_device_update(tz);
 735
 736         return count;
 737 }
 738
 739 static ssize_t
 740 passive_show(struct device *dev, struct device_attribute *attr,
 741                    char *buf)
 742 {
 743         struct thermal_zone_device *tz = to_thermal_zone(dev);
 744
 745         return sprintf(buf, "%d\n", tz->forced_passive);
 746 }
 747
 748 static ssize_t
 749 policy_store(struct device *dev, struct device_attribute *attr,
 750                     const char *buf, size_t count)
 751 {
 752         int ret = -EINVAL;
 753         struct thermal_zone_device *tz = to_thermal_zone(dev);
 754         struct thermal_governor *gov;
 755         char name[THERMAL_NAME_LENGTH];
 756
 757         snprintf(name, sizeof(name), "%s", buf);
 758
 759         mutex_lock(&thermal_governor_lock);
 760         mutex_lock(&tz->lock);
 761
 762         gov = __find_governor(strim(name));
 763         if (!gov)
 764                 goto exit;
 765
 766         tz->governor = gov;
 767         ret = count;
 768
 769 exit:
 770         mutex_unlock(&tz->lock);
 771         mutex_unlock(&thermal_governor_lock);
 772         return ret;
 773 }
 774
 775 static ssize_t
 776 policy_show(struct device *dev, struct device_attribute *devattr, char *buf)
 777 {
 778         struct thermal_zone_device *tz = to_thermal_zone(dev);
 779
 780         return sprintf(buf, "%s\n", tz->governor->name);
 781 }
 782
 783 #ifdef CONFIG_THERMAL_EMULATION
 784 static ssize_t
 785 emul_temp_store(struct device *dev, struct device_attribute *attr,
 786                      const char *buf, size_t count)
 787 {
 788         struct thermal_zone_device *tz = to_thermal_zone(dev);
 789         int ret = 0;
 790         unsigned long temperature;
 791
 792         if (kstrtoul(buf, 10, &temperature))
 793                 return -EINVAL;
 794
 795         if (!tz->ops->set_emul_temp) {
 796                 mutex_lock(&tz->lock);
 797                 tz->emul_temperature = temperature;
 798                 mutex_unlock(&tz->lock);
 799         } else {
 800                 ret = tz->ops->set_emul_temp(tz, temperature);
 801         }
 802
 803         if (!ret)
 804                 thermal_zone_device_update(tz);
 805
 806         return ret ? ret : count;
 807 }
 808 static DEVICE_ATTR(emul_temp, S_IWUSR, NULL, emul_temp_store);
 809 #endif/*CONFIG_THERMAL_EMULATION*/
 810
 811 static DEVICE_ATTR(type, 0444, type_show, NULL);
 812 static DEVICE_ATTR(temp, 0444, temp_show, NULL);
 813 static DEVICE_ATTR(mode, 0644, mode_show, mode_store);
 814 static DEVICE_ATTR(passive, S_IRUGO | S_IWUSR, passive_show, passive_store);
 815 static DEVICE_ATTR(policy, S_IRUGO | S_IWUSR, policy_show, policy_store);
 816
 817 /* sys I/F for cooling device */
 818 #define to_cooling_device(_dev) \
 819         container_of(_dev, struct thermal_cooling_device, device)
 820
 821 static ssize_t
 822 thermal_cooling_device_type_show(struct device *dev,
 823                                  struct device_attribute *attr, char *buf)
 824 {
 825         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 826
 827         return sprintf(buf, "%s\n", cdev->type);
 828 }
 829
 830 static ssize_t
 831 thermal_cooling_device_max_state_show(struct device *dev,
 832                                       struct device_attribute *attr, char *buf)
 833 {
 834         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 835         unsigned long state;
 836         int ret;
 837
 838         ret = cdev->ops->get_max_state(cdev, &state);
 839         if (ret)
 840                 return ret;
 841         return sprintf(buf, "%ld\n", state);
 842 }
 843
 844 static ssize_t
 845 thermal_cooling_device_cur_state_show(struct device *dev,
 846                                       struct device_attribute *attr, char *buf)
 847 {
 848         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 849         unsigned long state;
 850         int ret;
 851
 852         ret = cdev->ops->get_cur_state(cdev, &state);
 853         if (ret)
 854                 return ret;
 855         return sprintf(buf, "%ld\n", state);
 856 }
 857
 858 static ssize_t
 859 thermal_cooling_device_cur_state_store(struct device *dev,
 860                                        struct device_attribute *attr,
 861                                        const char *buf, size_t count)
 862 {
 863         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 864         unsigned long state;
 865         int result;
 866
 867         if (!sscanf(buf, "%ld\n", &state))
 868                 return -EINVAL;
 869
 870         if ((long)state < 0)
 871                 return -EINVAL;
 872
 873         result = cdev->ops->set_cur_state(cdev, state);
 874         if (result)
 875                 return result;
 876         return count;
 877 }
 878
 879 static struct device_attribute dev_attr_cdev_type =
 880 __ATTR(type, 0444, thermal_cooling_device_type_show, NULL);
 881 static DEVICE_ATTR(max_state, 0444,
 882                    thermal_cooling_device_max_state_show, NULL);
 883 static DEVICE_ATTR(cur_state, 0644,
 884                    thermal_cooling_device_cur_state_show,
 885                    thermal_cooling_device_cur_state_store);
 886
 887 static ssize_t
 888 thermal_cooling_device_trip_point_show(struct device *dev,
 889                                        struct device_attribute *attr, char *buf)
 890 {
 891         struct thermal_instance *instance;
 892
 893         instance =
 894             container_of(attr, struct thermal_instance, attr);
 895
 896         if (instance->trip == THERMAL_TRIPS_NONE)
 897                 return sprintf(buf, "-1\n");
 898         else
 899                 return sprintf(buf, "%d\n", instance->trip);
 900 }
 901
 902 /* Device management */
 903
 904 /**
 905  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 906  * @tz:         pointer to struct thermal_zone_device
 907  * @trip:       indicates which trip point the cooling devices is
 908  *              associated with in this thermal zone.
 909  * @cdev:       pointer to struct thermal_cooling_device
 910  * @upper:      the Maximum cooling state for this trip point.
 911  *              THERMAL_NO_LIMIT means no upper limit,
 912  *              and the cooling device can be in max_state.
 913  * @lower:      the Minimum cooling state can be used for this trip point.
 914  *              THERMAL_NO_LIMIT means no lower limit,
 915  *              and the cooling device can be in cooling state 0.
 916  *
 917  * This interface function bind a thermal cooling device to the certain trip
 918  * point of a thermal zone device.
 919  * This function is usually called in the thermal zone device .bind callback.
 920  *
 921  * Return: 0 on success, the proper error value otherwise.
 922  */
 923 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 924                                      int trip,
 925                                      struct thermal_cooling_device *cdev,
 926                                      unsigned long upper, unsigned long lower)
 927 {
 928         struct thermal_instance *dev;
 929         struct thermal_instance *pos;
 930         struct thermal_zone_device *pos1;
 931         struct thermal_cooling_device *pos2;
 932         unsigned long max_state;
 933         int result, ret;
 934
 935         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 936                 return -EINVAL;
 937
 938         list_for_each_entry(pos1, &thermal_tz_list, node) {
 939                 if (pos1 == tz)
 940                         break;
 941         }
 942         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 943                 if (pos2 == cdev)
 944                         break;
 945         }
 946
 947         if (tz != pos1 || cdev != pos2)
 948                 return -EINVAL;
 949
 950         ret = cdev->ops->get_max_state(cdev, &max_state);
 951         if (ret)
 952                 return ret;
 953
 954         /* lower default 0, upper default max_state */
 955         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 956         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 957
 958         if (lower > upper || upper > max_state)
 959                 return -EINVAL;
 960
 961         dev =
 962             kzalloc(sizeof(struct thermal_instance), GFP_KERNEL);
 963         if (!dev)
 964                 return -ENOMEM;
 965         dev->tz = tz;
 966         dev->cdev = cdev;
 967         dev->trip = trip;
 968         dev->upper = upper;
 969         dev->lower = lower;
 970         dev->target = THERMAL_NO_TARGET;
 971
 972         result = get_idr(&tz->idr, &tz->lock, &dev->id);
 973         if (result)
 974                 goto free_mem;
 975
 976         sprintf(dev->name, "cdev%d", dev->id);
 977         result =
 978             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 979         if (result)
 980                 goto release_idr;
 981
 982         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 983         sysfs_attr_init(&dev->attr.attr);
 984         dev->attr.attr.name = dev->attr_name;
 985         dev->attr.attr.mode = 0444;
 986         dev->attr.show = thermal_cooling_device_trip_point_show;
 987         result = device_create_file(&tz->device, &dev->attr);
 988         if (result)
 989                 goto remove_symbol_link;
 990
 991         mutex_lock(&tz->lock);
 992         mutex_lock(&cdev->lock);
 993         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 994             if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 995                 result = -EEXIST;
 996                 break;
 997         }
 998         if (!result) {
 999                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
1000                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
1001         }
1002         mutex_unlock(&cdev->lock);
1003         mutex_unlock(&tz->lock);
1004
1005         if (!result)
1006                 return 0;
1007
1008         device_remove_file(&tz->device, &dev->attr);
1009 remove_symbol_link:
1010         sysfs_remove_link(&tz->device.kobj, dev->name);
1011 release_idr:
1012         release_idr(&tz->idr, &tz->lock, dev->id);
1013 free_mem:
1014         kfree(dev);
1015         return result;
1016 }
1017 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
1018
1019 /**
1020  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
1021  *                                        thermal zone.
1022  * @tz:         pointer to a struct thermal_zone_device.
1023  * @trip:       indicates which trip point the cooling devices is
1024  *              associated with in this thermal zone.
1025  * @cdev:       pointer to a struct thermal_cooling_device.
1026  *
1027  * This interface function unbind a thermal cooling device from the certain
1028  * trip point of a thermal zone device.
1029  * This function is usually called in the thermal zone device .unbind callback.
1030  *
1031  * Return: 0 on success, the proper error value otherwise.
1032  */
1033 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
1034                                        int trip,
1035                                        struct thermal_cooling_device *cdev)
1036 {
1037         struct thermal_instance *pos, *next;
1038
1039         mutex_lock(&tz->lock);
1040         mutex_lock(&cdev->lock);
1041         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
1042                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
1043                         list_del(&pos->tz_node);
1044                         list_del(&pos->cdev_node);
1045                         mutex_unlock(&cdev->lock);
1046                         mutex_unlock(&tz->lock);
1047                         goto unbind;
1048                 }
1049         }
1050         mutex_unlock(&cdev->lock);
1051         mutex_unlock(&tz->lock);
1052
1053         return -ENODEV;
1054
1055 unbind:
1056         device_remove_file(&tz->device, &pos->attr);
1057         sysfs_remove_link(&tz->device.kobj, pos->name);
1058         release_idr(&tz->idr, &tz->lock, pos->id);
1059         kfree(pos);
1060         return 0;
1061 }
1062 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
1063
1064 static void thermal_release(struct device *dev)
1065 {
1066         struct thermal_zone_device *tz;
1067         struct thermal_cooling_device *cdev;
1068
1069         if (!strncmp(dev_name(dev), "thermal_zone",
1070                      sizeof("thermal_zone") - 1)) {
1071                 tz = to_thermal_zone(dev);
1072                 kfree(tz);
1073         } else if(!strncmp(dev_name(dev), "cooling_device",
1074                         sizeof("cooling_device") - 1)){
1075                 cdev = to_cooling_device(dev);
1076                 kfree(cdev);
1077         }
1078 }
1079
1080 static struct class thermal_class = {
1081         .name = "thermal",
1082         .dev_release = thermal_release,
1083 };
1084
1085 /**
1086  * __thermal_cooling_device_register() - register a new thermal cooling device
1087  * @np:         a pointer to a device tree node.
1088  * @type:       the thermal cooling device type.
1089  * @devdata:    device private data.
1090  * @ops:                standard thermal cooling devices callbacks.
1091  *
1092  * This interface function adds a new thermal cooling device (fan/processor/...)
1093  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1094  * to all the thermal zone devices registered at the same time.
1095  * It also gives the opportunity to link the cooling device to a device tree
1096  * node, so that it can be bound to a thermal zone created out of device tree.
1097  *
1098  * Return: a pointer to the created struct thermal_cooling_device or an
1099  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1100  */
1101 static struct thermal_cooling_device *
1102 __thermal_cooling_device_register(struct device_node *np,
1103                                   char *type, void *devdata,
1104                                   const struct thermal_cooling_device_ops *ops)
1105 {
1106         struct thermal_cooling_device *cdev;
1107         int result;
1108
1109         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1110                 return ERR_PTR(-EINVAL);
1111
1112         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1113             !ops->set_cur_state)
1114                 return ERR_PTR(-EINVAL);
1115
1116         cdev = kzalloc(sizeof(struct thermal_cooling_device), GFP_KERNEL);
1117         if (!cdev)
1118                 return ERR_PTR(-ENOMEM);
1119
1120         result = get_idr(&thermal_cdev_idr, &thermal_idr_lock, &cdev->id);
1121         if (result) {
1122                 kfree(cdev);
1123                 return ERR_PTR(result);
1124         }
1125
1126         strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
1127         mutex_init(&cdev->lock);
1128         INIT_LIST_HEAD(&cdev->thermal_instances);
1129         cdev->np = np;
1130         cdev->ops = ops;
1131         cdev->updated = false;
1132         cdev->device.class = &thermal_class;
1133         cdev->devdata = devdata;
1134         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1135         result = device_register(&cdev->device);
1136         if (result) {
1137                 release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
1138                 kfree(cdev);
1139                 return ERR_PTR(result);
1140         }
1141
1142         /* sys I/F */
1143         if (type) {
1144                 result = device_create_file(&cdev->device, &dev_attr_cdev_type);
1145                 if (result)
1146                         goto unregister;
1147         }
1148
1149         result = device_create_file(&cdev->device, &dev_attr_max_state);
1150         if (result)
1151                 goto unregister;
1152
1153         result = device_create_file(&cdev->device, &dev_attr_cur_state);
1154         if (result)
1155                 goto unregister;
1156
1157         /* Add 'this' new cdev to the global cdev list */
1158         mutex_lock(&thermal_list_lock);
1159         list_add(&cdev->node, &thermal_cdev_list);
1160         mutex_unlock(&thermal_list_lock);
1161
1162         /* Update binding information for 'this' new cdev */
1163         bind_cdev(cdev);
1164
1165         return cdev;
1166
1167 unregister:
1168         release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
1169         device_unregister(&cdev->device);
1170         return ERR_PTR(result);
1171 }
1172
1173 /**
1174  * thermal_cooling_device_register() - register a new thermal cooling device
1175  * @type:       the thermal cooling device type.
1176  * @devdata:    device private data.
1177  * @ops:                standard thermal cooling devices callbacks.
1178  *
1179  * This interface function adds a new thermal cooling device (fan/processor/...)
1180  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1181  * to all the thermal zone devices registered at the same time.
1182  *
1183  * Return: a pointer to the created struct thermal_cooling_device or an
1184  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1185  */
1186 struct thermal_cooling_device *
1187 thermal_cooling_device_register(char *type, void *devdata,
1188                                 const struct thermal_cooling_device_ops *ops)
1189 {
1190         return __thermal_cooling_device_register(NULL, type, devdata, ops);
1191 }
1192 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1193
1194 /**
1195  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1196  * @np:         a pointer to a device tree node.
1197  * @type:       the thermal cooling device type.
1198  * @devdata:    device private data.
1199  * @ops:                standard thermal cooling devices callbacks.
1200  *
1201  * This function will register a cooling device with device tree node reference.
1202  * This interface function adds a new thermal cooling device (fan/processor/...)
1203  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1204  * to all the thermal zone devices registered at the same time.
1205  *
1206  * Return: a pointer to the created struct thermal_cooling_device or an
1207  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1208  */
1209 struct thermal_cooling_device *
1210 thermal_of_cooling_device_register(struct device_node *np,
1211                                    char *type, void *devdata,
1212                                    const struct thermal_cooling_device_ops *ops)
1213 {
1214         return __thermal_cooling_device_register(np, type, devdata, ops);
1215 }
1216 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1217
1218 /**
1219  * thermal_cooling_device_unregister - removes the registered thermal cooling device
1220  * @cdev:       the thermal cooling device to remove.
1221  *
1222  * thermal_cooling_device_unregister() must be called when the device is no
1223  * longer needed.
1224  */
1225 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1226 {
1227         int i;
1228         const struct thermal_zone_params *tzp;
1229         struct thermal_zone_device *tz;
1230         struct thermal_cooling_device *pos = NULL;
1231
1232         if (!cdev)
1233                 return;
1234
1235         mutex_lock(&thermal_list_lock);
1236         list_for_each_entry(pos, &thermal_cdev_list, node)
1237             if (pos == cdev)
1238                 break;
1239         if (pos != cdev) {
1240                 /* thermal cooling device not found */
1241                 mutex_unlock(&thermal_list_lock);
1242                 return;
1243         }
1244         list_del(&cdev->node);
1245
1246         /* Unbind all thermal zones associated with 'this' cdev */
1247         list_for_each_entry(tz, &thermal_tz_list, node) {
1248                 if (tz->ops->unbind) {
1249                         tz->ops->unbind(tz, cdev);
1250                         continue;
1251                 }
1252
1253                 if (!tz->tzp || !tz->tzp->tbp)
1254                         continue;
1255
1256                 tzp = tz->tzp;
1257                 for (i = 0; i < tzp->num_tbps; i++) {
1258                         if (tzp->tbp[i].cdev == cdev) {
1259                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1260                                 tzp->tbp[i].cdev = NULL;
1261                         }
1262                 }
1263         }
1264
1265         mutex_unlock(&thermal_list_lock);
1266
1267         if (cdev->type[0])
1268                 device_remove_file(&cdev->device, &dev_attr_cdev_type);
1269         device_remove_file(&cdev->device, &dev_attr_max_state);
1270         device_remove_file(&cdev->device, &dev_attr_cur_state);
1271
1272         release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
1273         device_unregister(&cdev->device);
1274         return;
1275 }
1276 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1277
1278 void thermal_cdev_update(struct thermal_cooling_device *cdev)
1279 {
1280         struct thermal_instance *instance;
1281         unsigned long target = 0;
1282
1283         /* cooling device is updated*/
1284         if (cdev->updated)
1285                 return;
1286
1287         mutex_lock(&cdev->lock);
1288         /* Make sure cdev enters the deepest cooling state */
1289         list_for_each_entry(instance, &cdev->thermal_instances, cdev_node) {
1290                 dev_dbg(&cdev->device, "zone%d->target=%lu\n",
1291                                 instance->tz->id, instance->target);
1292                 if (instance->target == THERMAL_NO_TARGET)
1293                         continue;
1294                 if (instance->target > target)
1295                         target = instance->target;
1296         }
1297         mutex_unlock(&cdev->lock);
1298         cdev->ops->set_cur_state(cdev, target);
1299         cdev->updated = true;
1300         trace_cdev_update(cdev, target);
1301         dev_dbg(&cdev->device, "set to state %lu\n", target);
1302 }
1303 EXPORT_SYMBOL(thermal_cdev_update);
1304
1305 /**
1306  * thermal_notify_framework - Sensor drivers use this API to notify framework
1307  * @tz:         thermal zone device
1308  * @trip:       indicates which trip point has been crossed
1309  *
1310  * This function handles the trip events from sensor drivers. It starts
1311  * throttling the cooling devices according to the policy configured.
1312  * For CRITICAL and HOT trip points, this notifies the respective drivers,
1313  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
1314  * The throttling policy is based on the configured platform data; if no
1315  * platform data is provided, this uses the step_wise throttling policy.
1316  */
1317 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
1318 {
1319         handle_thermal_trip(tz, trip);
1320 }
1321 EXPORT_SYMBOL_GPL(thermal_notify_framework);
1322
1323 /**
1324  * create_trip_attrs() - create attributes for trip points
1325  * @tz:         the thermal zone device
1326  * @mask:       Writeable trip point bitmap.
1327  *
1328  * helper function to instantiate sysfs entries for every trip
1329  * point and its properties of a struct thermal_zone_device.
1330  *
1331  * Return: 0 on success, the proper error value otherwise.
1332  */
1333 static int create_trip_attrs(struct thermal_zone_device *tz, int mask)
1334 {
1335         int indx;
1336         int size = sizeof(struct thermal_attr) * tz->trips;
1337
1338         tz->trip_type_attrs = kzalloc(size, GFP_KERNEL);
1339         if (!tz->trip_type_attrs)
1340                 return -ENOMEM;
1341
1342         tz->trip_temp_attrs = kzalloc(size, GFP_KERNEL);
1343         if (!tz->trip_temp_attrs) {
1344                 kfree(tz->trip_type_attrs);
1345                 return -ENOMEM;
1346         }
1347
1348         if (tz->ops->get_trip_hyst) {
1349                 tz->trip_hyst_attrs = kzalloc(size, GFP_KERNEL);
1350                 if (!tz->trip_hyst_attrs) {
1351                         kfree(tz->trip_type_attrs);
1352                         kfree(tz->trip_temp_attrs);
1353                         return -ENOMEM;
1354                 }
1355         }
1356
1357
1358         for (indx = 0; indx < tz->trips; indx++) {
1359                 /* create trip type attribute */
1360                 snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH,
1361                          "trip_point_%d_type", indx);
1362
1363                 sysfs_attr_init(&tz->trip_type_attrs[indx].attr.attr);
1364                 tz->trip_type_attrs[indx].attr.attr.name =
1365                                                 tz->trip_type_attrs[indx].name;
1366                 tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;
1367                 tz->trip_type_attrs[indx].attr.show = trip_point_type_show;
1368
1369                 device_create_file(&tz->device,
1370                                    &tz->trip_type_attrs[indx].attr);
1371
1372                 /* create trip temp attribute */
1373                 snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH,
1374                          "trip_point_%d_temp", indx);
1375
1376                 sysfs_attr_init(&tz->trip_temp_attrs[indx].attr.attr);
1377                 tz->trip_temp_attrs[indx].attr.attr.name =
1378                                                 tz->trip_temp_attrs[indx].name;
1379                 tz->trip_temp_attrs[indx].attr.attr.mode = S_IRUGO;
1380                 tz->trip_temp_attrs[indx].attr.show = trip_point_temp_show;
1381                 if (mask & (1 << indx)) {
1382                         tz->trip_temp_attrs[indx].attr.attr.mode |= S_IWUSR;
1383                         tz->trip_temp_attrs[indx].attr.store =
1384                                                         trip_point_temp_store;
1385                 }
1386
1387                 device_create_file(&tz->device,
1388                                    &tz->trip_temp_attrs[indx].attr);
1389
1390                 /* create Optional trip hyst attribute */
1391                 if (!tz->ops->get_trip_hyst)
1392                         continue;
1393                 snprintf(tz->trip_hyst_attrs[indx].name, THERMAL_NAME_LENGTH,
1394                          "trip_point_%d_hyst", indx);
1395
1396                 sysfs_attr_init(&tz->trip_hyst_attrs[indx].attr.attr);
1397                 tz->trip_hyst_attrs[indx].attr.attr.name =
1398                                         tz->trip_hyst_attrs[indx].name;
1399                 tz->trip_hyst_attrs[indx].attr.attr.mode = S_IRUGO;
1400                 tz->trip_hyst_attrs[indx].attr.show = trip_point_hyst_show;
1401                 if (tz->ops->set_trip_hyst) {
1402                         tz->trip_hyst_attrs[indx].attr.attr.mode |= S_IWUSR;
1403                         tz->trip_hyst_attrs[indx].attr.store =
1404                                         trip_point_hyst_store;
1405                 }
1406
1407                 device_create_file(&tz->device,
1408                                    &tz->trip_hyst_attrs[indx].attr);
1409         }
1410         return 0;
1411 }
1412
1413 static void remove_trip_attrs(struct thermal_zone_device *tz)
1414 {
1415         int indx;
1416
1417         for (indx = 0; indx < tz->trips; indx++) {
1418                 device_remove_file(&tz->device,
1419                                    &tz->trip_type_attrs[indx].attr);
1420                 device_remove_file(&tz->device,
1421                                    &tz->trip_temp_attrs[indx].attr);
1422                 if (tz->ops->get_trip_hyst)
1423                         device_remove_file(&tz->device,
1424                                   &tz->trip_hyst_attrs[indx].attr);
1425         }
1426         kfree(tz->trip_type_attrs);
1427         kfree(tz->trip_temp_attrs);
1428         kfree(tz->trip_hyst_attrs);
1429 }
1430
1431 /**
1432  * thermal_zone_device_register() - register a new thermal zone device
1433  * @type:       the thermal zone device type
1434  * @trips:      the number of trip points the thermal zone support
1435  * @mask:       a bit string indicating the writeablility of trip points
1436  * @devdata:    private device data
1437  * @ops:        standard thermal zone device callbacks
1438  * @tzp:        thermal zone platform parameters
1439  * @passive_delay: number of milliseconds to wait between polls when
1440  *                 performing passive cooling
1441  * @polling_delay: number of milliseconds to wait between polls when checking
1442  *                 whether trip points have been crossed (0 for interrupt
1443  *                 driven systems)
1444  *
1445  * This interface function adds a new thermal zone device (sensor) to
1446  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1447  * thermal cooling devices registered at the same time.
1448  * thermal_zone_device_unregister() must be called when the device is no
1449  * longer needed. The passive cooling depends on the .get_trend() return value.
1450  *
1451  * Return: a pointer to the created struct thermal_zone_device or an
1452  * in case of error, an ERR_PTR. Caller must check return value with
1453  * IS_ERR*() helpers.
1454  */
1455 struct thermal_zone_device *thermal_zone_device_register(const char *type,
1456         int trips, int mask, void *devdata,
1457         struct thermal_zone_device_ops *ops,
1458         const struct thermal_zone_params *tzp,
1459         int passive_delay, int polling_delay)
1460 {
1461         struct thermal_zone_device *tz;
1462         enum thermal_trip_type trip_type;
1463         int result;
1464         int count;
1465         int passive = 0;
1466
1467         if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1468                 return ERR_PTR(-EINVAL);
1469
1470         if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
1471                 return ERR_PTR(-EINVAL);
1472
1473         if (!ops)
1474                 return ERR_PTR(-EINVAL);
1475
1476         if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1477                 return ERR_PTR(-EINVAL);
1478
1479         tz = kzalloc(sizeof(struct thermal_zone_device), GFP_KERNEL);
1480         if (!tz)
1481                 return ERR_PTR(-ENOMEM);
1482
1483         INIT_LIST_HEAD(&tz->thermal_instances);
1484         idr_init(&tz->idr);
1485         mutex_init(&tz->lock);
1486         result = get_idr(&thermal_tz_idr, &thermal_idr_lock, &tz->id);
1487         if (result) {
1488                 kfree(tz);
1489                 return ERR_PTR(result);
1490         }
1491
1492         strlcpy(tz->type, type ? : "", sizeof(tz->type));
1493         tz->ops = ops;
1494         tz->tzp = tzp;
1495         tz->device.class = &thermal_class;
1496         tz->devdata = devdata;
1497         tz->trips = trips;
1498         tz->passive_delay = passive_delay;
1499         tz->polling_delay = polling_delay;
1500
1501         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1502         result = device_register(&tz->device);
1503         if (result) {
1504                 release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1505                 kfree(tz);
1506                 return ERR_PTR(result);
1507         }
1508
1509         /* sys I/F */
1510         if (type) {
1511                 result = device_create_file(&tz->device, &dev_attr_type);
1512                 if (result)
1513                         goto unregister;
1514         }
1515
1516         result = device_create_file(&tz->device, &dev_attr_temp);
1517         if (result)
1518                 goto unregister;
1519
1520         if (ops->get_mode) {
1521                 result = device_create_file(&tz->device, &dev_attr_mode);
1522                 if (result)
1523                         goto unregister;
1524         }
1525
1526         result = create_trip_attrs(tz, mask);
1527         if (result)
1528                 goto unregister;
1529
1530         for (count = 0; count < trips; count++) {
1531                 tz->ops->get_trip_type(tz, count, &trip_type);
1532                 if (trip_type == THERMAL_TRIP_PASSIVE)
1533                         passive = 1;
1534         }
1535
1536         if (!passive) {
1537                 result = device_create_file(&tz->device, &dev_attr_passive);
1538                 if (result)
1539                         goto unregister;
1540         }
1541
1542 #ifdef CONFIG_THERMAL_EMULATION
1543         result = device_create_file(&tz->device, &dev_attr_emul_temp);
1544         if (result)
1545                 goto unregister;
1546 #endif
1547         /* Create policy attribute */
1548         result = device_create_file(&tz->device, &dev_attr_policy);
1549         if (result)
1550                 goto unregister;
1551
1552         /* Update 'this' zone's governor information */
1553         mutex_lock(&thermal_governor_lock);
1554
1555         if (tz->tzp)
1556                 tz->governor = __find_governor(tz->tzp->governor_name);
1557         else
1558                 tz->governor = def_governor;
1559
1560         mutex_unlock(&thermal_governor_lock);
1561
1562         if (!tz->tzp || !tz->tzp->no_hwmon) {
1563                 result = thermal_add_hwmon_sysfs(tz);
1564                 if (result)
1565                         goto unregister;
1566         }
1567
1568         mutex_lock(&thermal_list_lock);
1569         list_add_tail(&tz->node, &thermal_tz_list);
1570         mutex_unlock(&thermal_list_lock);
1571
1572         /* Bind cooling devices for this zone */
1573         bind_tz(tz);
1574
1575         INIT_DELAYED_WORK(&(tz->poll_queue), thermal_zone_device_check);
1576
1577         if (!tz->ops->get_temp)
1578                 thermal_zone_device_set_polling(tz, 0);
1579
1580         thermal_zone_device_update(tz);
1581
1582         return tz;
1583
1584 unregister:
1585         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1586         device_unregister(&tz->device);
1587         return ERR_PTR(result);
1588 }
1589 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1590
1591 /**
1592  * thermal_device_unregister - removes the registered thermal zone device
1593  * @tz: the thermal zone device to remove
1594  */
1595 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1596 {
1597         int i;
1598         const struct thermal_zone_params *tzp;
1599         struct thermal_cooling_device *cdev;
1600         struct thermal_zone_device *pos = NULL;
1601
1602         if (!tz)
1603                 return;
1604
1605         tzp = tz->tzp;
1606
1607         mutex_lock(&thermal_list_lock);
1608         list_for_each_entry(pos, &thermal_tz_list, node)
1609             if (pos == tz)
1610                 break;
1611         if (pos != tz) {
1612                 /* thermal zone device not found */
1613                 mutex_unlock(&thermal_list_lock);
1614                 return;
1615         }
1616         list_del(&tz->node);
1617
1618         /* Unbind all cdevs associated with 'this' thermal zone */
1619         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1620                 if (tz->ops->unbind) {
1621                         tz->ops->unbind(tz, cdev);
1622                         continue;
1623                 }
1624
1625                 if (!tzp || !tzp->tbp)
1626                         break;
1627
1628                 for (i = 0; i < tzp->num_tbps; i++) {
1629                         if (tzp->tbp[i].cdev == cdev) {
1630                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1631                                 tzp->tbp[i].cdev = NULL;
1632                         }
1633                 }
1634         }
1635
1636         mutex_unlock(&thermal_list_lock);
1637
1638         thermal_zone_device_set_polling(tz, 0);
1639
1640         if (tz->type[0])
1641                 device_remove_file(&tz->device, &dev_attr_type);
1642         device_remove_file(&tz->device, &dev_attr_temp);
1643         if (tz->ops->get_mode)
1644                 device_remove_file(&tz->device, &dev_attr_mode);
1645         device_remove_file(&tz->device, &dev_attr_policy);
1646         remove_trip_attrs(tz);
1647         tz->governor = NULL;
1648
1649         thermal_remove_hwmon_sysfs(tz);
1650         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1651         idr_destroy(&tz->idr);
1652         mutex_destroy(&tz->lock);
1653         device_unregister(&tz->device);
1654         return;
1655 }
1656 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1657
1658 /**
1659  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1660  * @name: thermal zone name to fetch the temperature
1661  *
1662  * When only one zone is found with the passed name, returns a reference to it.
1663  *
1664  * Return: On success returns a reference to an unique thermal zone with
1665  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1666  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1667  */
1668 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1669 {
1670         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1671         unsigned int found = 0;
1672
1673         if (!name)
1674                 goto exit;
1675
1676         mutex_lock(&thermal_list_lock);
1677         list_for_each_entry(pos, &thermal_tz_list, node)
1678                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1679                         found++;
1680                         ref = pos;
1681                 }
1682         mutex_unlock(&thermal_list_lock);
1683
1684         /* nothing has been found, thus an error code for it */
1685         if (found == 0)
1686                 ref = ERR_PTR(-ENODEV);
1687         else if (found > 1)
1688         /* Success only when an unique zone is found */
1689                 ref = ERR_PTR(-EEXIST);
1690
1691 exit:
1692         return ref;
1693 }
1694 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1695
1696 #ifdef CONFIG_NET
1697 static const struct genl_multicast_group thermal_event_mcgrps[] = {
1698         { .name = THERMAL_GENL_MCAST_GROUP_NAME, },
1699 };
1700
1701 static struct genl_family thermal_event_genl_family = {
1702         .id = GENL_ID_GENERATE,
1703         .name = THERMAL_GENL_FAMILY_NAME,
1704         .version = THERMAL_GENL_VERSION,
1705         .maxattr = THERMAL_GENL_ATTR_MAX,
1706         .mcgrps = thermal_event_mcgrps,
1707         .n_mcgrps = ARRAY_SIZE(thermal_event_mcgrps),
1708 };
1709
1710 int thermal_generate_netlink_event(struct thermal_zone_device *tz,
1711                                         enum events event)
1712 {
1713         struct sk_buff *skb;
1714         struct nlattr *attr;
1715         struct thermal_genl_event *thermal_event;
1716         void *msg_header;
1717         int size;
1718         int result;
1719         static unsigned int thermal_event_seqnum;
1720
1721         if (!tz)
1722                 return -EINVAL;
1723
1724         /* allocate memory */
1725         size = nla_total_size(sizeof(struct thermal_genl_event)) +
1726                nla_total_size(0);
1727
1728         skb = genlmsg_new(size, GFP_ATOMIC);
1729         if (!skb)
1730                 return -ENOMEM;
1731
1732         /* add the genetlink message header */
1733         msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++,
1734                                  &thermal_event_genl_family, 0,
1735                                  THERMAL_GENL_CMD_EVENT);
1736         if (!msg_header) {
1737                 nlmsg_free(skb);
1738                 return -ENOMEM;
1739         }
1740
1741         /* fill the data */
1742         attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT,
1743                            sizeof(struct thermal_genl_event));
1744
1745         if (!attr) {
1746                 nlmsg_free(skb);
1747                 return -EINVAL;
1748         }
1749
1750         thermal_event = nla_data(attr);
1751         if (!thermal_event) {
1752                 nlmsg_free(skb);
1753                 return -EINVAL;
1754         }
1755
1756         memset(thermal_event, 0, sizeof(struct thermal_genl_event));
1757
1758         thermal_event->orig = tz->id;
1759         thermal_event->event = event;
1760
1761         /* send multicast genetlink message */
1762         genlmsg_end(skb, msg_header);
1763
1764         result = genlmsg_multicast(&thermal_event_genl_family, skb, 0,
1765                                    0, GFP_ATOMIC);
1766         if (result)
1767                 dev_err(&tz->device, "Failed to send netlink event:%d", result);
1768
1769         return result;
1770 }
1771 EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
1772
1773 static int genetlink_init(void)
1774 {
1775         return genl_register_family(&thermal_event_genl_family);
1776 }
1777
1778 static void genetlink_exit(void)
1779 {
1780         genl_unregister_family(&thermal_event_genl_family);
1781 }
1782 #else /* !CONFIG_NET */
1783 static inline int genetlink_init(void) { return 0; }
1784 static inline void genetlink_exit(void) {}
1785 #endif /* !CONFIG_NET */
1786
1787 static int __init thermal_register_governors(void)
1788 {
1789         int result;
1790
1791         result = thermal_gov_step_wise_register();
1792         if (result)
1793                 return result;
1794
1795         result = thermal_gov_fair_share_register();
1796         if (result)
1797                 return result;
1798
1799         result = thermal_gov_bang_bang_register();
1800         if (result)
1801                 return result;
1802
1803         return thermal_gov_user_space_register();
1804 }
1805
1806 static void thermal_unregister_governors(void)
1807 {
1808         thermal_gov_step_wise_unregister();
1809         thermal_gov_fair_share_unregister();
1810         thermal_gov_bang_bang_unregister();
1811         thermal_gov_user_space_unregister();
1812 }
1813
1814 static int __init thermal_init(void)
1815 {
1816         int result;
1817
1818         result = thermal_register_governors();
1819         if (result)
1820                 goto error;
1821
1822         result = class_register(&thermal_class);
1823         if (result)
1824                 goto unregister_governors;
1825
1826         result = genetlink_init();
1827         if (result)
1828                 goto unregister_class;
1829
1830         result = of_parse_thermal_zones();
1831         if (result)
1832                 goto exit_netlink;
1833
1834         return 0;
1835
1836 exit_netlink:
1837         genetlink_exit();
1838 unregister_class:
1839         class_unregister(&thermal_class);
1840 unregister_governors:
1841         thermal_unregister_governors();
1842 error:
1843         idr_destroy(&thermal_tz_idr);
1844         idr_destroy(&thermal_cdev_idr);
1845         mutex_destroy(&thermal_idr_lock);
1846         mutex_destroy(&thermal_list_lock);
1847         mutex_destroy(&thermal_governor_lock);
1848         return result;
1849 }
1850
1851 static void __exit thermal_exit(void)
1852 {
1853         of_thermal_destroy_zones();
1854         genetlink_exit();
1855         class_unregister(&thermal_class);
1856         thermal_unregister_governors();
1857         idr_destroy(&thermal_tz_idr);
1858         idr_destroy(&thermal_cdev_idr);
1859         mutex_destroy(&thermal_idr_lock);
1860         mutex_destroy(&thermal_list_lock);
1861         mutex_destroy(&thermal_governor_lock);
1862 }
1863
1864 fs_initcall(thermal_init);
1865 module_exit(thermal_exit);