drivers/thermal/thermal.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 #include <linux/module.h>
  27 #include <linux/device.h>
  28 #include <linux/err.h>
  29 #include <linux/kdev_t.h>
  30 #include <linux/idr.h>
  31 #include <linux/thermal.h>
  32 #include <linux/spinlock.h>
  33
  34 MODULE_AUTHOR("Zhang Rui")
  35 MODULE_DESCRIPTION("Generic thermal management sysfs support");
  36 MODULE_LICENSE("GPL");
  37
  38 #define PREFIX "Thermal: "
  39
  40 struct thermal_cooling_device_instance {
  41         int id;
  42         char name[THERMAL_NAME_LENGTH];
  43         struct thermal_zone_device *tz;
  44         struct thermal_cooling_device *cdev;
  45         int trip;
  46         char attr_name[THERMAL_NAME_LENGTH];
  47         struct device_attribute attr;
  48         struct list_head node;
  49 };
  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 DEFINE_MUTEX(thermal_list_lock);
  58
  59 static int get_idr(struct idr *idr, struct mutex *lock, int *id)
  60 {
  61         int err;
  62
  63       again:
  64         if (unlikely(idr_pre_get(idr, GFP_KERNEL) == 0))
  65                 return -ENOMEM;
  66
  67         if (lock)
  68                 mutex_lock(lock);
  69         err = idr_get_new(idr, NULL, id);
  70         if (lock)
  71                 mutex_unlock(lock);
  72         if (unlikely(err == -EAGAIN))
  73                 goto again;
  74         else if (unlikely(err))
  75                 return err;
  76
  77         *id = *id & MAX_ID_MASK;
  78         return 0;
  79 }
  80
  81 static void release_idr(struct idr *idr, struct mutex *lock, int id)
  82 {
  83         if (lock)
  84                 mutex_lock(lock);
  85         idr_remove(idr, id);
  86         if (lock)
  87                 mutex_unlock(lock);
  88 }
  89
  90 /* sys I/F for thermal zone */
  91
  92 #define to_thermal_zone(_dev) \
  93         container_of(_dev, struct thermal_zone_device, device)
  94
  95 static ssize_t
  96 type_show(struct device *dev, struct device_attribute *attr, char *buf)
  97 {
  98         struct thermal_zone_device *tz = to_thermal_zone(dev);
  99
 100         return sprintf(buf, "%s\n", tz->type);
 101 }
 102
 103 static ssize_t
 104 temp_show(struct device *dev, struct device_attribute *attr, char *buf)
 105 {
 106         struct thermal_zone_device *tz = to_thermal_zone(dev);
 107
 108         if (!tz->ops->get_temp)
 109                 return -EPERM;
 110
 111         return tz->ops->get_temp(tz, buf);
 112 }
 113
 114 static ssize_t
 115 mode_show(struct device *dev, struct device_attribute *attr, char *buf)
 116 {
 117         struct thermal_zone_device *tz = to_thermal_zone(dev);
 118
 119         if (!tz->ops->get_mode)
 120                 return -EPERM;
 121
 122         return tz->ops->get_mode(tz, buf);
 123 }
 124
 125 static ssize_t
 126 mode_store(struct device *dev, struct device_attribute *attr,
 127            const char *buf, size_t count)
 128 {
 129         struct thermal_zone_device *tz = to_thermal_zone(dev);
 130         int result;
 131
 132         if (!tz->ops->set_mode)
 133                 return -EPERM;
 134
 135         result = tz->ops->set_mode(tz, buf);
 136         if (result)
 137                 return result;
 138
 139         return count;
 140 }
 141
 142 static ssize_t
 143 trip_point_type_show(struct device *dev, struct device_attribute *attr,
 144                      char *buf)
 145 {
 146         struct thermal_zone_device *tz = to_thermal_zone(dev);
 147         int trip;
 148
 149         if (!tz->ops->get_trip_type)
 150                 return -EPERM;
 151
 152         if (!sscanf(attr->attr.name, "trip_point_%d_type", &trip))
 153                 return -EINVAL;
 154
 155         return tz->ops->get_trip_type(tz, trip, buf);
 156 }
 157
 158 static ssize_t
 159 trip_point_temp_show(struct device *dev, struct device_attribute *attr,
 160                      char *buf)
 161 {
 162         struct thermal_zone_device *tz = to_thermal_zone(dev);
 163         int trip;
 164
 165         if (!tz->ops->get_trip_temp)
 166                 return -EPERM;
 167
 168         if (!sscanf(attr->attr.name, "trip_point_%d_temp", &trip))
 169                 return -EINVAL;
 170
 171         return tz->ops->get_trip_temp(tz, trip, buf);
 172 }
 173
 174 static DEVICE_ATTR(type, 0444, type_show, NULL);
 175 static DEVICE_ATTR(temp, 0444, temp_show, NULL);
 176 static DEVICE_ATTR(mode, 0644, mode_show, mode_store);
 177
 178 static struct device_attribute trip_point_attrs[] = {
 179         __ATTR(trip_point_0_type, 0444, trip_point_type_show, NULL),
 180         __ATTR(trip_point_0_temp, 0444, trip_point_temp_show, NULL),
 181         __ATTR(trip_point_1_type, 0444, trip_point_type_show, NULL),
 182         __ATTR(trip_point_1_temp, 0444, trip_point_temp_show, NULL),
 183         __ATTR(trip_point_2_type, 0444, trip_point_type_show, NULL),
 184         __ATTR(trip_point_2_temp, 0444, trip_point_temp_show, NULL),
 185         __ATTR(trip_point_3_type, 0444, trip_point_type_show, NULL),
 186         __ATTR(trip_point_3_temp, 0444, trip_point_temp_show, NULL),
 187         __ATTR(trip_point_4_type, 0444, trip_point_type_show, NULL),
 188         __ATTR(trip_point_4_temp, 0444, trip_point_temp_show, NULL),
 189         __ATTR(trip_point_5_type, 0444, trip_point_type_show, NULL),
 190         __ATTR(trip_point_5_temp, 0444, trip_point_temp_show, NULL),
 191         __ATTR(trip_point_6_type, 0444, trip_point_type_show, NULL),
 192         __ATTR(trip_point_6_temp, 0444, trip_point_temp_show, NULL),
 193         __ATTR(trip_point_7_type, 0444, trip_point_type_show, NULL),
 194         __ATTR(trip_point_7_temp, 0444, trip_point_temp_show, NULL),
 195         __ATTR(trip_point_8_type, 0444, trip_point_type_show, NULL),
 196         __ATTR(trip_point_8_temp, 0444, trip_point_temp_show, NULL),
 197         __ATTR(trip_point_9_type, 0444, trip_point_type_show, NULL),
 198         __ATTR(trip_point_9_temp, 0444, trip_point_temp_show, NULL),
 199         __ATTR(trip_point_10_type, 0444, trip_point_type_show, NULL),
 200         __ATTR(trip_point_10_temp, 0444, trip_point_temp_show, NULL),
 201         __ATTR(trip_point_11_type, 0444, trip_point_type_show, NULL),
 202         __ATTR(trip_point_11_temp, 0444, trip_point_temp_show, NULL),
 203 };
 204
 205 #define TRIP_POINT_ATTR_ADD(_dev, _index, result)     \
 206 do {    \
 207         result = device_create_file(_dev,       \
 208                                 &trip_point_attrs[_index * 2]); \
 209         if (result)     \
 210                 break;  \
 211         result = device_create_file(_dev,       \
 212                         &trip_point_attrs[_index * 2 + 1]);     \
 213 } while (0)
 214
 215 #define TRIP_POINT_ATTR_REMOVE(_dev, _index)    \
 216 do {    \
 217         device_remove_file(_dev, &trip_point_attrs[_index * 2]);        \
 218         device_remove_file(_dev, &trip_point_attrs[_index * 2 + 1]);    \
 219 } while (0)
 220
 221 /* sys I/F for cooling device */
 222 #define to_cooling_device(_dev) \
 223         container_of(_dev, struct thermal_cooling_device, device)
 224
 225 static ssize_t
 226 thermal_cooling_device_type_show(struct device *dev,
 227                                  struct device_attribute *attr, char *buf)
 228 {
 229         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 230
 231         return sprintf(buf, "%s\n", cdev->type);
 232 }
 233
 234 static ssize_t
 235 thermal_cooling_device_max_state_show(struct device *dev,
 236                                       struct device_attribute *attr, char *buf)
 237 {
 238         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 239
 240         return cdev->ops->get_max_state(cdev, buf);
 241 }
 242
 243 static ssize_t
 244 thermal_cooling_device_cur_state_show(struct device *dev,
 245                                       struct device_attribute *attr, char *buf)
 246 {
 247         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 248
 249         return cdev->ops->get_cur_state(cdev, buf);
 250 }
 251
 252 static ssize_t
 253 thermal_cooling_device_cur_state_store(struct device *dev,
 254                                        struct device_attribute *attr,
 255                                        const char *buf, size_t count)
 256 {
 257         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 258         int state;
 259         int result;
 260
 261         if (!sscanf(buf, "%d\n", &state))
 262                 return -EINVAL;
 263
 264         if (state < 0)
 265                 return -EINVAL;
 266
 267         result = cdev->ops->set_cur_state(cdev, state);
 268         if (result)
 269                 return result;
 270         return count;
 271 }
 272
 273 static struct device_attribute dev_attr_cdev_type =
 274 __ATTR(type, 0444, thermal_cooling_device_type_show, NULL);
 275 static DEVICE_ATTR(max_state, 0444,
 276                    thermal_cooling_device_max_state_show, NULL);
 277 static DEVICE_ATTR(cur_state, 0644,
 278                    thermal_cooling_device_cur_state_show,
 279                    thermal_cooling_device_cur_state_store);
 280
 281 static ssize_t
 282 thermal_cooling_device_trip_point_show(struct device *dev,
 283                                        struct device_attribute *attr, char *buf)
 284 {
 285         struct thermal_cooling_device_instance *instance;
 286
 287         instance =
 288             container_of(attr, struct thermal_cooling_device_instance, attr);
 289
 290         if (instance->trip == THERMAL_TRIPS_NONE)
 291                 return sprintf(buf, "-1\n");
 292         else
 293                 return sprintf(buf, "%d\n", instance->trip);
 294 }
 295
 296 /* Device management */
 297
 298 /**
 299  * thermal_zone_bind_cooling_device - bind a cooling device to a thermal zone
 300  * @tz:         thermal zone device
 301  * @trip:       indicates which trip point the cooling devices is
 302  *              associated with in this thermal zone.
 303  * @cdev:       thermal cooling device
 304  *
 305  * This function is usually called in the thermal zone device .bind callback.
 306  */
 307 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 308                                      int trip,
 309                                      struct thermal_cooling_device *cdev)
 310 {
 311         struct thermal_cooling_device_instance *dev;
 312         struct thermal_cooling_device_instance *pos;
 313         struct thermal_zone_device *pos1;
 314         struct thermal_cooling_device *pos2;
 315         int result;
 316
 317         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 318                 return -EINVAL;
 319
 320         list_for_each_entry(pos1, &thermal_tz_list, node) {
 321                 if (pos1 == tz)
 322                         break;
 323         }
 324         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 325                 if (pos2 == cdev)
 326                         break;
 327         }
 328
 329         if (tz != pos1 || cdev != pos2)
 330                 return -EINVAL;
 331
 332         dev =
 333             kzalloc(sizeof(struct thermal_cooling_device_instance), GFP_KERNEL);
 334         if (!dev)
 335                 return -ENOMEM;
 336         dev->tz = tz;
 337         dev->cdev = cdev;
 338         dev->trip = trip;
 339         result = get_idr(&tz->idr, &tz->lock, &dev->id);
 340         if (result)
 341                 goto free_mem;
 342
 343         sprintf(dev->name, "cdev%d", dev->id);
 344         result =
 345             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 346         if (result)
 347                 goto release_idr;
 348
 349         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 350         dev->attr.attr.name = dev->attr_name;
 351         dev->attr.attr.mode = 0444;
 352         dev->attr.show = thermal_cooling_device_trip_point_show;
 353         result = device_create_file(&tz->device, &dev->attr);
 354         if (result)
 355                 goto remove_symbol_link;
 356
 357         mutex_lock(&tz->lock);
 358         list_for_each_entry(pos, &tz->cooling_devices, node)
 359             if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 360                 result = -EEXIST;
 361                 break;
 362         }
 363         if (!result)
 364                 list_add_tail(&dev->node, &tz->cooling_devices);
 365         mutex_unlock(&tz->lock);
 366
 367         if (!result)
 368                 return 0;
 369
 370         device_remove_file(&tz->device, &dev->attr);
 371       remove_symbol_link:
 372         sysfs_remove_link(&tz->device.kobj, dev->name);
 373       release_idr:
 374         release_idr(&tz->idr, &tz->lock, dev->id);
 375       free_mem:
 376         kfree(dev);
 377         return result;
 378 }
 379
 380 EXPORT_SYMBOL(thermal_zone_bind_cooling_device);
 381
 382 /**
 383  * thermal_zone_unbind_cooling_device - unbind a cooling device from a thermal zone
 384  * @tz:         thermal zone device
 385  * @trip:       indicates which trip point the cooling devices is
 386  *              associated with in this thermal zone.
 387  * @cdev:       thermal cooling device
 388  *
 389  * This function is usually called in the thermal zone device .unbind callback.
 390  */
 391 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 392                                        int trip,
 393                                        struct thermal_cooling_device *cdev)
 394 {
 395         struct thermal_cooling_device_instance *pos, *next;
 396
 397         mutex_lock(&tz->lock);
 398         list_for_each_entry_safe(pos, next, &tz->cooling_devices, node) {
 399                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 400                         list_del(&pos->node);
 401                         mutex_unlock(&tz->lock);
 402                         goto unbind;
 403                 }
 404         }
 405         mutex_unlock(&tz->lock);
 406
 407         return -ENODEV;
 408
 409       unbind:
 410         device_remove_file(&tz->device, &pos->attr);
 411         sysfs_remove_link(&tz->device.kobj, pos->name);
 412         release_idr(&tz->idr, &tz->lock, pos->id);
 413         kfree(pos);
 414         return 0;
 415 }
 416
 417 EXPORT_SYMBOL(thermal_zone_unbind_cooling_device);
 418
 419 static void thermal_release(struct device *dev)
 420 {
 421         struct thermal_zone_device *tz;
 422         struct thermal_cooling_device *cdev;
 423
 424         if (!strncmp(dev->bus_id, "thermal_zone", sizeof "thermal_zone" - 1)) {
 425                 tz = to_thermal_zone(dev);
 426                 kfree(tz);
 427         } else {
 428                 cdev = to_cooling_device(dev);
 429                 kfree(cdev);
 430         }
 431 }
 432
 433 static struct class thermal_class = {
 434         .name = "thermal",
 435         .dev_release = thermal_release,
 436 };
 437
 438 /**
 439  * thermal_cooling_device_register - register a new thermal cooling device
 440  * @type:       the thermal cooling device type.
 441  * @devdata:    device private data.
 442  * @ops:                standard thermal cooling devices callbacks.
 443  */
 444 struct thermal_cooling_device *thermal_cooling_device_register(char *type,
 445                                                                void *devdata,
 446                                                                struct
 447                                                                thermal_cooling_device_ops
 448                                                                *ops)
 449 {
 450         struct thermal_cooling_device *cdev;
 451         struct thermal_zone_device *pos;
 452         int result;
 453
 454         if (strlen(type) >= THERMAL_NAME_LENGTH)
 455                 return ERR_PTR(-EINVAL);
 456
 457         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 458             !ops->set_cur_state)
 459                 return ERR_PTR(-EINVAL);
 460
 461         cdev = kzalloc(sizeof(struct thermal_cooling_device), GFP_KERNEL);
 462         if (!cdev)
 463                 return ERR_PTR(-ENOMEM);
 464
 465         result = get_idr(&thermal_cdev_idr, &thermal_idr_lock, &cdev->id);
 466         if (result) {
 467                 kfree(cdev);
 468                 return ERR_PTR(result);
 469         }
 470
 471         strcpy(cdev->type, type);
 472         cdev->ops = ops;
 473         cdev->device.class = &thermal_class;
 474         cdev->devdata = devdata;
 475         sprintf(cdev->device.bus_id, "cooling_device%d", cdev->id);
 476         result = device_register(&cdev->device);
 477         if (result) {
 478                 release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
 479                 kfree(cdev);
 480                 return ERR_PTR(result);
 481         }
 482
 483         /* sys I/F */
 484         if (type) {
 485                 result = device_create_file(&cdev->device, &dev_attr_cdev_type);
 486                 if (result)
 487                         goto unregister;
 488         }
 489
 490         result = device_create_file(&cdev->device, &dev_attr_max_state);
 491         if (result)
 492                 goto unregister;
 493
 494         result = device_create_file(&cdev->device, &dev_attr_cur_state);
 495         if (result)
 496                 goto unregister;
 497
 498         mutex_lock(&thermal_list_lock);
 499         list_add(&cdev->node, &thermal_cdev_list);
 500         list_for_each_entry(pos, &thermal_tz_list, node) {
 501                 if (!pos->ops->bind)
 502                         continue;
 503                 result = pos->ops->bind(pos, cdev);
 504                 if (result)
 505                         break;
 506
 507         }
 508         mutex_unlock(&thermal_list_lock);
 509
 510         if (!result)
 511                 return cdev;
 512
 513       unregister:
 514         release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
 515         device_unregister(&cdev->device);
 516         return ERR_PTR(result);
 517 }
 518
 519 EXPORT_SYMBOL(thermal_cooling_device_register);
 520
 521 /**
 522  * thermal_cooling_device_unregister - removes the registered thermal cooling device
 523  * @cdev:       the thermal cooling device to remove.
 524  *
 525  * thermal_cooling_device_unregister() must be called when the device is no
 526  * longer needed.
 527  */
 528 void thermal_cooling_device_unregister(struct
 529                                        thermal_cooling_device
 530                                        *cdev)
 531 {
 532         struct thermal_zone_device *tz;
 533         struct thermal_cooling_device *pos = NULL;
 534
 535         if (!cdev)
 536                 return;
 537
 538         mutex_lock(&thermal_list_lock);
 539         list_for_each_entry(pos, &thermal_cdev_list, node)
 540             if (pos == cdev)
 541                 break;
 542         if (pos != cdev) {
 543                 /* thermal cooling device not found */
 544                 mutex_unlock(&thermal_list_lock);
 545                 return;
 546         }
 547         list_del(&cdev->node);
 548         list_for_each_entry(tz, &thermal_tz_list, node) {
 549                 if (!tz->ops->unbind)
 550                         continue;
 551                 tz->ops->unbind(tz, cdev);
 552         }
 553         mutex_unlock(&thermal_list_lock);
 554         if (cdev->type[0])
 555                 device_remove_file(&cdev->device, &dev_attr_cdev_type);
 556         device_remove_file(&cdev->device, &dev_attr_max_state);
 557         device_remove_file(&cdev->device, &dev_attr_cur_state);
 558
 559         release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
 560         device_unregister(&cdev->device);
 561         return;
 562 }
 563
 564 EXPORT_SYMBOL(thermal_cooling_device_unregister);
 565
 566 /**
 567  * thermal_zone_device_register - register a new thermal zone device
 568  * @type:       the thermal zone device type
 569  * @trips:      the number of trip points the thermal zone support
 570  * @devdata:    private device data
 571  * @ops:        standard thermal zone device callbacks
 572  *
 573  * thermal_zone_device_unregister() must be called when the device is no
 574  * longer needed.
 575  */
 576 struct thermal_zone_device *thermal_zone_device_register(char *type,
 577                                                          int trips,
 578                                                          void *devdata, struct
 579                                                          thermal_zone_device_ops
 580                                                          *ops)
 581 {
 582         struct thermal_zone_device *tz;
 583         struct thermal_cooling_device *pos;
 584         int result;
 585         int count;
 586
 587         if (strlen(type) >= THERMAL_NAME_LENGTH)
 588                 return ERR_PTR(-EINVAL);
 589
 590         if (trips > THERMAL_MAX_TRIPS || trips < 0)
 591                 return ERR_PTR(-EINVAL);
 592
 593         if (!ops || !ops->get_temp)
 594                 return ERR_PTR(-EINVAL);
 595
 596         tz = kzalloc(sizeof(struct thermal_zone_device), GFP_KERNEL);
 597         if (!tz)
 598                 return ERR_PTR(-ENOMEM);
 599
 600         INIT_LIST_HEAD(&tz->cooling_devices);
 601         idr_init(&tz->idr);
 602         mutex_init(&tz->lock);
 603         result = get_idr(&thermal_tz_idr, &thermal_idr_lock, &tz->id);
 604         if (result) {
 605                 kfree(tz);
 606                 return ERR_PTR(result);
 607         }
 608
 609         strcpy(tz->type, type);
 610         tz->ops = ops;
 611         tz->device.class = &thermal_class;
 612         tz->devdata = devdata;
 613         tz->trips = trips;
 614         sprintf(tz->device.bus_id, "thermal_zone%d", tz->id);
 615         result = device_register(&tz->device);
 616         if (result) {
 617                 release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
 618                 kfree(tz);
 619                 return ERR_PTR(result);
 620         }
 621
 622         /* sys I/F */
 623         if (type) {
 624                 result = device_create_file(&tz->device, &dev_attr_type);
 625                 if (result)
 626                         goto unregister;
 627         }
 628
 629         result = device_create_file(&tz->device, &dev_attr_temp);
 630         if (result)
 631                 goto unregister;
 632
 633         if (ops->get_mode) {
 634                 result = device_create_file(&tz->device, &dev_attr_mode);
 635                 if (result)
 636                         goto unregister;
 637         }
 638
 639         for (count = 0; count < trips; count++) {
 640                 TRIP_POINT_ATTR_ADD(&tz->device, count, result);
 641                 if (result)
 642                         goto unregister;
 643         }
 644
 645         mutex_lock(&thermal_list_lock);
 646         list_add_tail(&tz->node, &thermal_tz_list);
 647         if (ops->bind)
 648                 list_for_each_entry(pos, &thermal_cdev_list, node) {
 649                 result = ops->bind(tz, pos);
 650                 if (result)
 651                         break;
 652                 }
 653         mutex_unlock(&thermal_list_lock);
 654
 655         if (!result)
 656                 return tz;
 657
 658       unregister:
 659         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
 660         device_unregister(&tz->device);
 661         return ERR_PTR(result);
 662 }
 663
 664 EXPORT_SYMBOL(thermal_zone_device_register);
 665
 666 /**
 667  * thermal_device_unregister - removes the registered thermal zone device
 668  * @tz: the thermal zone device to remove
 669  */
 670 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
 671 {
 672         struct thermal_cooling_device *cdev;
 673         struct thermal_zone_device *pos = NULL;
 674         int count;
 675
 676         if (!tz)
 677                 return;
 678
 679         mutex_lock(&thermal_list_lock);
 680         list_for_each_entry(pos, &thermal_tz_list, node)
 681             if (pos == tz)
 682                 break;
 683         if (pos != tz) {
 684                 /* thermal zone device not found */
 685                 mutex_unlock(&thermal_list_lock);
 686                 return;
 687         }
 688         list_del(&tz->node);
 689         if (tz->ops->unbind)
 690                 list_for_each_entry(cdev, &thermal_cdev_list, node)
 691                     tz->ops->unbind(tz, cdev);
 692         mutex_unlock(&thermal_list_lock);
 693
 694         if (tz->type[0])
 695                 device_remove_file(&tz->device, &dev_attr_type);
 696         device_remove_file(&tz->device, &dev_attr_temp);
 697         if (tz->ops->get_mode)
 698                 device_remove_file(&tz->device, &dev_attr_mode);
 699
 700         for (count = 0; count < tz->trips; count++)
 701                 TRIP_POINT_ATTR_REMOVE(&tz->device, count);
 702
 703         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
 704         idr_destroy(&tz->idr);
 705         mutex_destroy(&tz->lock);
 706         device_unregister(&tz->device);
 707         return;
 708 }
 709
 710 EXPORT_SYMBOL(thermal_zone_device_unregister);
 711
 712 static int __init thermal_init(void)
 713 {
 714         int result = 0;
 715
 716         result = class_register(&thermal_class);
 717         if (result) {
 718                 idr_destroy(&thermal_tz_idr);
 719                 idr_destroy(&thermal_cdev_idr);
 720                 mutex_destroy(&thermal_idr_lock);
 721                 mutex_destroy(&thermal_list_lock);
 722         }
 723         return result;
 724 }
 725
 726 static void __exit thermal_exit(void)
 727 {
 728         class_unregister(&thermal_class);
 729         idr_destroy(&thermal_tz_idr);
 730         idr_destroy(&thermal_cdev_idr);
 731         mutex_destroy(&thermal_idr_lock);
 732         mutex_destroy(&thermal_list_lock);
 733 }
 734
 735 subsys_initcall(thermal_init);
 736 module_exit(thermal_exit);