drivers/thermal/thermal_sys.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 #include <linux/reboot.h>
  34
  35 MODULE_AUTHOR("Zhang Rui");
  36 MODULE_DESCRIPTION("Generic thermal management sysfs support");
  37 MODULE_LICENSE("GPL");
  38
  39 #define PREFIX "Thermal: "
  40
  41 struct thermal_cooling_device_instance {
  42         int id;
  43         char name[THERMAL_NAME_LENGTH];
  44         struct thermal_zone_device *tz;
  45         struct thermal_cooling_device *cdev;
  46         int trip;
  47         char attr_name[THERMAL_NAME_LENGTH];
  48         struct device_attribute attr;
  49         struct list_head node;
  50 };
  51
  52 static DEFINE_IDR(thermal_tz_idr);
  53 static DEFINE_IDR(thermal_cdev_idr);
  54 static DEFINE_MUTEX(thermal_idr_lock);
  55
  56 static LIST_HEAD(thermal_tz_list);
  57 static LIST_HEAD(thermal_cdev_list);
  58 static DEFINE_MUTEX(thermal_list_lock);
  59
  60 static int get_idr(struct idr *idr, struct mutex *lock, int *id)
  61 {
  62         int err;
  63
  64       again:
  65         if (unlikely(idr_pre_get(idr, GFP_KERNEL) == 0))
  66                 return -ENOMEM;
  67
  68         if (lock)
  69                 mutex_lock(lock);
  70         err = idr_get_new(idr, NULL, id);
  71         if (lock)
  72                 mutex_unlock(lock);
  73         if (unlikely(err == -EAGAIN))
  74                 goto again;
  75         else if (unlikely(err))
  76                 return err;
  77
  78         *id = *id & MAX_ID_MASK;
  79         return 0;
  80 }
  81
  82 static void release_idr(struct idr *idr, struct mutex *lock, int id)
  83 {
  84         if (lock)
  85                 mutex_lock(lock);
  86         idr_remove(idr, id);
  87         if (lock)
  88                 mutex_unlock(lock);
  89 }
  90
  91 /* sys I/F for thermal zone */
  92
  93 #define to_thermal_zone(_dev) \
  94         container_of(_dev, struct thermal_zone_device, device)
  95
  96 static ssize_t
  97 type_show(struct device *dev, struct device_attribute *attr, char *buf)
  98 {
  99         struct thermal_zone_device *tz = to_thermal_zone(dev);
 100
 101         return sprintf(buf, "%s\n", tz->type);
 102 }
 103
 104 static ssize_t
 105 temp_show(struct device *dev, struct device_attribute *attr, char *buf)
 106 {
 107         struct thermal_zone_device *tz = to_thermal_zone(dev);
 108         long temperature;
 109         int ret;
 110
 111         if (!tz->ops->get_temp)
 112                 return -EPERM;
 113
 114         ret = tz->ops->get_temp(tz, &temperature);
 115
 116         if (ret)
 117                 return ret;
 118
 119         return sprintf(buf, "%ld\n", temperature);
 120 }
 121
 122 static ssize_t
 123 mode_show(struct device *dev, struct device_attribute *attr, char *buf)
 124 {
 125         struct thermal_zone_device *tz = to_thermal_zone(dev);
 126         enum thermal_device_mode mode;
 127         int result;
 128
 129         if (!tz->ops->get_mode)
 130                 return -EPERM;
 131
 132         result = tz->ops->get_mode(tz, &mode);
 133         if (result)
 134                 return result;
 135
 136         return sprintf(buf, "%s\n", mode == THERMAL_DEVICE_ENABLED ? "enabled"
 137                        : "disabled");
 138 }
 139
 140 static ssize_t
 141 mode_store(struct device *dev, struct device_attribute *attr,
 142            const char *buf, size_t count)
 143 {
 144         struct thermal_zone_device *tz = to_thermal_zone(dev);
 145         int result;
 146
 147         if (!tz->ops->set_mode)
 148                 return -EPERM;
 149
 150         if (!strncmp(buf, "enabled", sizeof("enabled")))
 151                 result = tz->ops->set_mode(tz, THERMAL_DEVICE_ENABLED);
 152         else if (!strncmp(buf, "disabled", sizeof("disabled")))
 153                 result = tz->ops->set_mode(tz, THERMAL_DEVICE_DISABLED);
 154         else
 155                 result = -EINVAL;
 156
 157         if (result)
 158                 return result;
 159
 160         return count;
 161 }
 162
 163 static ssize_t
 164 trip_point_type_show(struct device *dev, struct device_attribute *attr,
 165                      char *buf)
 166 {
 167         struct thermal_zone_device *tz = to_thermal_zone(dev);
 168         enum thermal_trip_type type;
 169         int trip, result;
 170
 171         if (!tz->ops->get_trip_type)
 172                 return -EPERM;
 173
 174         if (!sscanf(attr->attr.name, "trip_point_%d_type", &trip))
 175                 return -EINVAL;
 176
 177         result = tz->ops->get_trip_type(tz, trip, &type);
 178         if (result)
 179                 return result;
 180
 181         switch (type) {
 182         case THERMAL_TRIP_CRITICAL:
 183                 return sprintf(buf, "critical");
 184         case THERMAL_TRIP_HOT:
 185                 return sprintf(buf, "hot");
 186         case THERMAL_TRIP_PASSIVE:
 187                 return sprintf(buf, "passive");
 188         case THERMAL_TRIP_ACTIVE:
 189                 return sprintf(buf, "active");
 190         default:
 191                 return sprintf(buf, "unknown");
 192         }
 193 }
 194
 195 static ssize_t
 196 trip_point_temp_show(struct device *dev, struct device_attribute *attr,
 197                      char *buf)
 198 {
 199         struct thermal_zone_device *tz = to_thermal_zone(dev);
 200         int trip, ret;
 201         long temperature;
 202
 203         if (!tz->ops->get_trip_temp)
 204                 return -EPERM;
 205
 206         if (!sscanf(attr->attr.name, "trip_point_%d_temp", &trip))
 207                 return -EINVAL;
 208
 209         ret = tz->ops->get_trip_temp(tz, trip, &temperature);
 210
 211         if (ret)
 212                 return ret;
 213
 214         return sprintf(buf, "%ld\n", temperature);
 215 }
 216
 217 static ssize_t
 218 passive_store(struct device *dev, struct device_attribute *attr,
 219                     const char *buf, size_t count)
 220 {
 221         struct thermal_zone_device *tz = to_thermal_zone(dev);
 222         struct thermal_cooling_device *cdev = NULL;
 223         int state;
 224
 225         if (!sscanf(buf, "%d\n", &state))
 226                 return -EINVAL;
 227
 228         if (state && !tz->forced_passive) {
 229                 mutex_lock(&thermal_list_lock);
 230                 list_for_each_entry(cdev, &thermal_cdev_list, node) {
 231                         if (!strncmp("Processor", cdev->type,
 232                                      sizeof("Processor")))
 233                                 thermal_zone_bind_cooling_device(tz,
 234                                                                  THERMAL_TRIPS_NONE,
 235                                                                  cdev);
 236                 }
 237                 mutex_unlock(&thermal_list_lock);
 238         } else if (!state && tz->forced_passive) {
 239                 mutex_lock(&thermal_list_lock);
 240                 list_for_each_entry(cdev, &thermal_cdev_list, node) {
 241                         if (!strncmp("Processor", cdev->type,
 242                                      sizeof("Processor")))
 243                                 thermal_zone_unbind_cooling_device(tz,
 244                                                                    THERMAL_TRIPS_NONE,
 245                                                                    cdev);
 246                 }
 247                 mutex_unlock(&thermal_list_lock);
 248         }
 249
 250         tz->tc1 = 1;
 251         tz->tc2 = 1;
 252
 253         if (!tz->passive_delay)
 254                 tz->passive_delay = 1000;
 255
 256         if (!tz->polling_delay)
 257                 tz->polling_delay = 10000;
 258
 259         tz->forced_passive = state;
 260
 261         thermal_zone_device_update(tz);
 262
 263         return count;
 264 }
 265
 266 static ssize_t
 267 passive_show(struct device *dev, struct device_attribute *attr,
 268                    char *buf)
 269 {
 270         struct thermal_zone_device *tz = to_thermal_zone(dev);
 271
 272         return sprintf(buf, "%d\n", tz->forced_passive);
 273 }
 274
 275 static DEVICE_ATTR(type, 0444, type_show, NULL);
 276 static DEVICE_ATTR(temp, 0444, temp_show, NULL);
 277 static DEVICE_ATTR(mode, 0644, mode_show, mode_store);
 278 static DEVICE_ATTR(passive, S_IRUGO | S_IWUSR, passive_show, \
 279                    passive_store);
 280
 281 static struct device_attribute trip_point_attrs[] = {
 282         __ATTR(trip_point_0_type, 0444, trip_point_type_show, NULL),
 283         __ATTR(trip_point_0_temp, 0444, trip_point_temp_show, NULL),
 284         __ATTR(trip_point_1_type, 0444, trip_point_type_show, NULL),
 285         __ATTR(trip_point_1_temp, 0444, trip_point_temp_show, NULL),
 286         __ATTR(trip_point_2_type, 0444, trip_point_type_show, NULL),
 287         __ATTR(trip_point_2_temp, 0444, trip_point_temp_show, NULL),
 288         __ATTR(trip_point_3_type, 0444, trip_point_type_show, NULL),
 289         __ATTR(trip_point_3_temp, 0444, trip_point_temp_show, NULL),
 290         __ATTR(trip_point_4_type, 0444, trip_point_type_show, NULL),
 291         __ATTR(trip_point_4_temp, 0444, trip_point_temp_show, NULL),
 292         __ATTR(trip_point_5_type, 0444, trip_point_type_show, NULL),
 293         __ATTR(trip_point_5_temp, 0444, trip_point_temp_show, NULL),
 294         __ATTR(trip_point_6_type, 0444, trip_point_type_show, NULL),
 295         __ATTR(trip_point_6_temp, 0444, trip_point_temp_show, NULL),
 296         __ATTR(trip_point_7_type, 0444, trip_point_type_show, NULL),
 297         __ATTR(trip_point_7_temp, 0444, trip_point_temp_show, NULL),
 298         __ATTR(trip_point_8_type, 0444, trip_point_type_show, NULL),
 299         __ATTR(trip_point_8_temp, 0444, trip_point_temp_show, NULL),
 300         __ATTR(trip_point_9_type, 0444, trip_point_type_show, NULL),
 301         __ATTR(trip_point_9_temp, 0444, trip_point_temp_show, NULL),
 302         __ATTR(trip_point_10_type, 0444, trip_point_type_show, NULL),
 303         __ATTR(trip_point_10_temp, 0444, trip_point_temp_show, NULL),
 304         __ATTR(trip_point_11_type, 0444, trip_point_type_show, NULL),
 305         __ATTR(trip_point_11_temp, 0444, trip_point_temp_show, NULL),
 306 };
 307
 308 #define TRIP_POINT_ATTR_ADD(_dev, _index, result)     \
 309 do {    \
 310         result = device_create_file(_dev,       \
 311                                 &trip_point_attrs[_index * 2]); \
 312         if (result)     \
 313                 break;  \
 314         result = device_create_file(_dev,       \
 315                         &trip_point_attrs[_index * 2 + 1]);     \
 316 } while (0)
 317
 318 #define TRIP_POINT_ATTR_REMOVE(_dev, _index)    \
 319 do {    \
 320         device_remove_file(_dev, &trip_point_attrs[_index * 2]);        \
 321         device_remove_file(_dev, &trip_point_attrs[_index * 2 + 1]);    \
 322 } while (0)
 323
 324 /* sys I/F for cooling device */
 325 #define to_cooling_device(_dev) \
 326         container_of(_dev, struct thermal_cooling_device, device)
 327
 328 static ssize_t
 329 thermal_cooling_device_type_show(struct device *dev,
 330                                  struct device_attribute *attr, char *buf)
 331 {
 332         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 333
 334         return sprintf(buf, "%s\n", cdev->type);
 335 }
 336
 337 static ssize_t
 338 thermal_cooling_device_max_state_show(struct device *dev,
 339                                       struct device_attribute *attr, char *buf)
 340 {
 341         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 342         unsigned long state;
 343         int ret;
 344
 345         ret = cdev->ops->get_max_state(cdev, &state);
 346         if (ret)
 347                 return ret;
 348         return sprintf(buf, "%ld\n", state);
 349 }
 350
 351 static ssize_t
 352 thermal_cooling_device_cur_state_show(struct device *dev,
 353                                       struct device_attribute *attr, char *buf)
 354 {
 355         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 356         unsigned long state;
 357         int ret;
 358
 359         ret = cdev->ops->get_cur_state(cdev, &state);
 360         if (ret)
 361                 return ret;
 362         return sprintf(buf, "%ld\n", state);
 363 }
 364
 365 static ssize_t
 366 thermal_cooling_device_cur_state_store(struct device *dev,
 367                                        struct device_attribute *attr,
 368                                        const char *buf, size_t count)
 369 {
 370         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 371         unsigned long state;
 372         int result;
 373
 374         if (!sscanf(buf, "%ld\n", &state))
 375                 return -EINVAL;
 376
 377         if (state < 0)
 378                 return -EINVAL;
 379
 380         result = cdev->ops->set_cur_state(cdev, state);
 381         if (result)
 382                 return result;
 383         return count;
 384 }
 385
 386 static struct device_attribute dev_attr_cdev_type =
 387 __ATTR(type, 0444, thermal_cooling_device_type_show, NULL);
 388 static DEVICE_ATTR(max_state, 0444,
 389                    thermal_cooling_device_max_state_show, NULL);
 390 static DEVICE_ATTR(cur_state, 0644,
 391                    thermal_cooling_device_cur_state_show,
 392                    thermal_cooling_device_cur_state_store);
 393
 394 static ssize_t
 395 thermal_cooling_device_trip_point_show(struct device *dev,
 396                                        struct device_attribute *attr, char *buf)
 397 {
 398         struct thermal_cooling_device_instance *instance;
 399
 400         instance =
 401             container_of(attr, struct thermal_cooling_device_instance, attr);
 402
 403         if (instance->trip == THERMAL_TRIPS_NONE)
 404                 return sprintf(buf, "-1\n");
 405         else
 406                 return sprintf(buf, "%d\n", instance->trip);
 407 }
 408
 409 /* Device management */
 410
 411 #if defined(CONFIG_THERMAL_HWMON)
 412
 413 /* hwmon sys I/F */
 414 #include <linux/hwmon.h>
 415 static LIST_HEAD(thermal_hwmon_list);
 416
 417 static ssize_t
 418 name_show(struct device *dev, struct device_attribute *attr, char *buf)
 419 {
 420         struct thermal_hwmon_device *hwmon = dev->driver_data;
 421         return sprintf(buf, "%s\n", hwmon->type);
 422 }
 423 static DEVICE_ATTR(name, 0444, name_show, NULL);
 424
 425 static ssize_t
 426 temp_input_show(struct device *dev, struct device_attribute *attr, char *buf)
 427 {
 428         long temperature;
 429         int ret;
 430         struct thermal_hwmon_attr *hwmon_attr
 431                         = container_of(attr, struct thermal_hwmon_attr, attr);
 432         struct thermal_zone_device *tz
 433                         = container_of(hwmon_attr, struct thermal_zone_device,
 434                                        temp_input);
 435
 436         ret = tz->ops->get_temp(tz, &temperature);
 437
 438         if (ret)
 439                 return ret;
 440
 441         return sprintf(buf, "%ld\n", temperature);
 442 }
 443
 444 static ssize_t
 445 temp_crit_show(struct device *dev, struct device_attribute *attr,
 446                 char *buf)
 447 {
 448         struct thermal_hwmon_attr *hwmon_attr
 449                         = container_of(attr, struct thermal_hwmon_attr, attr);
 450         struct thermal_zone_device *tz
 451                         = container_of(hwmon_attr, struct thermal_zone_device,
 452                                        temp_crit);
 453         long temperature;
 454         int ret;
 455
 456         ret = tz->ops->get_trip_temp(tz, 0, &temperature);
 457         if (ret)
 458                 return ret;
 459
 460         return sprintf(buf, "%ld\n", temperature);
 461 }
 462
 463
 464 static int
 465 thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
 466 {
 467         struct thermal_hwmon_device *hwmon;
 468         int new_hwmon_device = 1;
 469         int result;
 470
 471         mutex_lock(&thermal_list_lock);
 472         list_for_each_entry(hwmon, &thermal_hwmon_list, node)
 473                 if (!strcmp(hwmon->type, tz->type)) {
 474                         new_hwmon_device = 0;
 475                         mutex_unlock(&thermal_list_lock);
 476                         goto register_sys_interface;
 477                 }
 478         mutex_unlock(&thermal_list_lock);
 479
 480         hwmon = kzalloc(sizeof(struct thermal_hwmon_device), GFP_KERNEL);
 481         if (!hwmon)
 482                 return -ENOMEM;
 483
 484         INIT_LIST_HEAD(&hwmon->tz_list);
 485         strlcpy(hwmon->type, tz->type, THERMAL_NAME_LENGTH);
 486         hwmon->device = hwmon_device_register(NULL);
 487         if (IS_ERR(hwmon->device)) {
 488                 result = PTR_ERR(hwmon->device);
 489                 goto free_mem;
 490         }
 491         hwmon->device->driver_data = hwmon;
 492         result = device_create_file(hwmon->device, &dev_attr_name);
 493         if (result)
 494                 goto unregister_hwmon_device;
 495
 496  register_sys_interface:
 497         tz->hwmon = hwmon;
 498         hwmon->count++;
 499
 500         snprintf(tz->temp_input.name, THERMAL_NAME_LENGTH,
 501                  "temp%d_input", hwmon->count);
 502         tz->temp_input.attr.attr.name = tz->temp_input.name;
 503         tz->temp_input.attr.attr.mode = 0444;
 504         tz->temp_input.attr.show = temp_input_show;
 505         result = device_create_file(hwmon->device, &tz->temp_input.attr);
 506         if (result)
 507                 goto unregister_hwmon_device;
 508
 509         if (tz->ops->get_crit_temp) {
 510                 unsigned long temperature;
 511                 if (!tz->ops->get_crit_temp(tz, &temperature)) {
 512                         snprintf(tz->temp_crit.name, THERMAL_NAME_LENGTH,
 513                                 "temp%d_crit", hwmon->count);
 514                         tz->temp_crit.attr.attr.name = tz->temp_crit.name;
 515                         tz->temp_crit.attr.attr.mode = 0444;
 516                         tz->temp_crit.attr.show = temp_crit_show;
 517                         result = device_create_file(hwmon->device,
 518                                                     &tz->temp_crit.attr);
 519                         if (result)
 520                                 goto unregister_hwmon_device;
 521                 }
 522         }
 523
 524         mutex_lock(&thermal_list_lock);
 525         if (new_hwmon_device)
 526                 list_add_tail(&hwmon->node, &thermal_hwmon_list);
 527         list_add_tail(&tz->hwmon_node, &hwmon->tz_list);
 528         mutex_unlock(&thermal_list_lock);
 529
 530         return 0;
 531
 532  unregister_hwmon_device:
 533         device_remove_file(hwmon->device, &tz->temp_crit.attr);
 534         device_remove_file(hwmon->device, &tz->temp_input.attr);
 535         if (new_hwmon_device) {
 536                 device_remove_file(hwmon->device, &dev_attr_name);
 537                 hwmon_device_unregister(hwmon->device);
 538         }
 539  free_mem:
 540         if (new_hwmon_device)
 541                 kfree(hwmon);
 542
 543         return result;
 544 }
 545
 546 static void
 547 thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
 548 {
 549         struct thermal_hwmon_device *hwmon = tz->hwmon;
 550
 551         tz->hwmon = NULL;
 552         device_remove_file(hwmon->device, &tz->temp_input.attr);
 553         device_remove_file(hwmon->device, &tz->temp_crit.attr);
 554
 555         mutex_lock(&thermal_list_lock);
 556         list_del(&tz->hwmon_node);
 557         if (!list_empty(&hwmon->tz_list)) {
 558                 mutex_unlock(&thermal_list_lock);
 559                 return;
 560         }
 561         list_del(&hwmon->node);
 562         mutex_unlock(&thermal_list_lock);
 563
 564         device_remove_file(hwmon->device, &dev_attr_name);
 565         hwmon_device_unregister(hwmon->device);
 566         kfree(hwmon);
 567 }
 568 #else
 569 static int
 570 thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
 571 {
 572         return 0;
 573 }
 574
 575 static void
 576 thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
 577 {
 578 }
 579 #endif
 580
 581 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 582                                             int delay)
 583 {
 584         cancel_delayed_work(&(tz->poll_queue));
 585
 586         if (!delay)
 587                 return;
 588
 589         if (delay > 1000)
 590                 schedule_delayed_work(&(tz->poll_queue),
 591                                       round_jiffies(msecs_to_jiffies(delay)));
 592         else
 593                 schedule_delayed_work(&(tz->poll_queue),
 594                                       msecs_to_jiffies(delay));
 595 }
 596
 597 static void thermal_zone_device_passive(struct thermal_zone_device *tz,
 598                                         int temp, int trip_temp, int trip)
 599 {
 600         int trend = 0;
 601         struct thermal_cooling_device_instance *instance;
 602         struct thermal_cooling_device *cdev;
 603         long state, max_state;
 604
 605         /*
 606          * Above Trip?
 607          * -----------
 608          * Calculate the thermal trend (using the passive cooling equation)
 609          * and modify the performance limit for all passive cooling devices
 610          * accordingly.  Note that we assume symmetry.
 611          */
 612         if (temp >= trip_temp) {
 613                 tz->passive = true;
 614
 615                 trend = (tz->tc1 * (temp - tz->last_temperature)) +
 616                         (tz->tc2 * (temp - trip_temp));
 617
 618                 /* Heating up? */
 619                 if (trend > 0) {
 620                         list_for_each_entry(instance, &tz->cooling_devices,
 621                                             node) {
 622                                 if (instance->trip != trip)
 623                                         continue;
 624                                 cdev = instance->cdev;
 625                                 cdev->ops->get_cur_state(cdev, &state);
 626                                 cdev->ops->get_max_state(cdev, &max_state);
 627                                 if (state++ < max_state)
 628                                         cdev->ops->set_cur_state(cdev, state);
 629                         }
 630                 } else if (trend < 0) { /* Cooling off? */
 631                         list_for_each_entry(instance, &tz->cooling_devices,
 632                                             node) {
 633                                 if (instance->trip != trip)
 634                                         continue;
 635                                 cdev = instance->cdev;
 636                                 cdev->ops->get_cur_state(cdev, &state);
 637                                 cdev->ops->get_max_state(cdev, &max_state);
 638                                 if (state > 0)
 639                                         cdev->ops->set_cur_state(cdev, --state);
 640                         }
 641                 }
 642                 return;
 643         }
 644
 645         /*
 646          * Below Trip?
 647          * -----------
 648          * Implement passive cooling hysteresis to slowly increase performance
 649          * and avoid thrashing around the passive trip point.  Note that we
 650          * assume symmetry.
 651          */
 652         list_for_each_entry(instance, &tz->cooling_devices, node) {
 653                 if (instance->trip != trip)
 654                         continue;
 655                 cdev = instance->cdev;
 656                 cdev->ops->get_cur_state(cdev, &state);
 657                 cdev->ops->get_max_state(cdev, &max_state);
 658                 if (state > 0)
 659                         cdev->ops->set_cur_state(cdev, --state);
 660                 if (state == 0)
 661                         tz->passive = false;
 662         }
 663 }
 664
 665 static void thermal_zone_device_check(struct work_struct *work)
 666 {
 667         struct thermal_zone_device *tz = container_of(work, struct
 668                                                       thermal_zone_device,
 669                                                       poll_queue.work);
 670         thermal_zone_device_update(tz);
 671 }
 672
 673 /**
 674  * thermal_zone_bind_cooling_device - bind a cooling device to a thermal zone
 675  * @tz:         thermal zone device
 676  * @trip:       indicates which trip point the cooling devices is
 677  *              associated with in this thermal zone.
 678  * @cdev:       thermal cooling device
 679  *
 680  * This function is usually called in the thermal zone device .bind callback.
 681  */
 682 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 683                                      int trip,
 684                                      struct thermal_cooling_device *cdev)
 685 {
 686         struct thermal_cooling_device_instance *dev;
 687         struct thermal_cooling_device_instance *pos;
 688         struct thermal_zone_device *pos1;
 689         struct thermal_cooling_device *pos2;
 690         int result;
 691
 692         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 693                 return -EINVAL;
 694
 695         list_for_each_entry(pos1, &thermal_tz_list, node) {
 696                 if (pos1 == tz)
 697                         break;
 698         }
 699         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 700                 if (pos2 == cdev)
 701                         break;
 702         }
 703
 704         if (tz != pos1 || cdev != pos2)
 705                 return -EINVAL;
 706
 707         dev =
 708             kzalloc(sizeof(struct thermal_cooling_device_instance), GFP_KERNEL);
 709         if (!dev)
 710                 return -ENOMEM;
 711         dev->tz = tz;
 712         dev->cdev = cdev;
 713         dev->trip = trip;
 714         result = get_idr(&tz->idr, &tz->lock, &dev->id);
 715         if (result)
 716                 goto free_mem;
 717
 718         sprintf(dev->name, "cdev%d", dev->id);
 719         result =
 720             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 721         if (result)
 722                 goto release_idr;
 723
 724         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 725         dev->attr.attr.name = dev->attr_name;
 726         dev->attr.attr.mode = 0444;
 727         dev->attr.show = thermal_cooling_device_trip_point_show;
 728         result = device_create_file(&tz->device, &dev->attr);
 729         if (result)
 730                 goto remove_symbol_link;
 731
 732         mutex_lock(&tz->lock);
 733         list_for_each_entry(pos, &tz->cooling_devices, node)
 734             if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 735                 result = -EEXIST;
 736                 break;
 737         }
 738         if (!result)
 739                 list_add_tail(&dev->node, &tz->cooling_devices);
 740         mutex_unlock(&tz->lock);
 741
 742         if (!result)
 743                 return 0;
 744
 745         device_remove_file(&tz->device, &dev->attr);
 746       remove_symbol_link:
 747         sysfs_remove_link(&tz->device.kobj, dev->name);
 748       release_idr:
 749         release_idr(&tz->idr, &tz->lock, dev->id);
 750       free_mem:
 751         kfree(dev);
 752         return result;
 753 }
 754
 755 EXPORT_SYMBOL(thermal_zone_bind_cooling_device);
 756
 757 /**
 758  * thermal_zone_unbind_cooling_device - unbind a cooling device from a thermal zone
 759  * @tz:         thermal zone device
 760  * @trip:       indicates which trip point the cooling devices is
 761  *              associated with in this thermal zone.
 762  * @cdev:       thermal cooling device
 763  *
 764  * This function is usually called in the thermal zone device .unbind callback.
 765  */
 766 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 767                                        int trip,
 768                                        struct thermal_cooling_device *cdev)
 769 {
 770         struct thermal_cooling_device_instance *pos, *next;
 771
 772         mutex_lock(&tz->lock);
 773         list_for_each_entry_safe(pos, next, &tz->cooling_devices, node) {
 774                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 775                         list_del(&pos->node);
 776                         mutex_unlock(&tz->lock);
 777                         goto unbind;
 778                 }
 779         }
 780         mutex_unlock(&tz->lock);
 781
 782         return -ENODEV;
 783
 784       unbind:
 785         device_remove_file(&tz->device, &pos->attr);
 786         sysfs_remove_link(&tz->device.kobj, pos->name);
 787         release_idr(&tz->idr, &tz->lock, pos->id);
 788         kfree(pos);
 789         return 0;
 790 }
 791
 792 EXPORT_SYMBOL(thermal_zone_unbind_cooling_device);
 793
 794 static void thermal_release(struct device *dev)
 795 {
 796         struct thermal_zone_device *tz;
 797         struct thermal_cooling_device *cdev;
 798
 799         if (!strncmp(dev_name(dev), "thermal_zone", sizeof "thermal_zone" - 1)) {
 800                 tz = to_thermal_zone(dev);
 801                 kfree(tz);
 802         } else {
 803                 cdev = to_cooling_device(dev);
 804                 kfree(cdev);
 805         }
 806 }
 807
 808 static struct class thermal_class = {
 809         .name = "thermal",
 810         .dev_release = thermal_release,
 811 };
 812
 813 /**
 814  * thermal_cooling_device_register - register a new thermal cooling device
 815  * @type:       the thermal cooling device type.
 816  * @devdata:    device private data.
 817  * @ops:                standard thermal cooling devices callbacks.
 818  */
 819 struct thermal_cooling_device *thermal_cooling_device_register(char *type,
 820                                                                void *devdata,
 821                                                                struct
 822                                                                thermal_cooling_device_ops
 823                                                                *ops)
 824 {
 825         struct thermal_cooling_device *cdev;
 826         struct thermal_zone_device *pos;
 827         int result;
 828
 829         if (strlen(type) >= THERMAL_NAME_LENGTH)
 830                 return ERR_PTR(-EINVAL);
 831
 832         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 833             !ops->set_cur_state)
 834                 return ERR_PTR(-EINVAL);
 835
 836         cdev = kzalloc(sizeof(struct thermal_cooling_device), GFP_KERNEL);
 837         if (!cdev)
 838                 return ERR_PTR(-ENOMEM);
 839
 840         result = get_idr(&thermal_cdev_idr, &thermal_idr_lock, &cdev->id);
 841         if (result) {
 842                 kfree(cdev);
 843                 return ERR_PTR(result);
 844         }
 845
 846         strcpy(cdev->type, type);
 847         cdev->ops = ops;
 848         cdev->device.class = &thermal_class;
 849         cdev->devdata = devdata;
 850         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 851         result = device_register(&cdev->device);
 852         if (result) {
 853                 release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
 854                 kfree(cdev);
 855                 return ERR_PTR(result);
 856         }
 857
 858         /* sys I/F */
 859         if (type) {
 860                 result = device_create_file(&cdev->device, &dev_attr_cdev_type);
 861                 if (result)
 862                         goto unregister;
 863         }
 864
 865         result = device_create_file(&cdev->device, &dev_attr_max_state);
 866         if (result)
 867                 goto unregister;
 868
 869         result = device_create_file(&cdev->device, &dev_attr_cur_state);
 870         if (result)
 871                 goto unregister;
 872
 873         mutex_lock(&thermal_list_lock);
 874         list_add(&cdev->node, &thermal_cdev_list);
 875         list_for_each_entry(pos, &thermal_tz_list, node) {
 876                 if (!pos->ops->bind)
 877                         continue;
 878                 result = pos->ops->bind(pos, cdev);
 879                 if (result)
 880                         break;
 881
 882         }
 883         mutex_unlock(&thermal_list_lock);
 884
 885         if (!result)
 886                 return cdev;
 887
 888       unregister:
 889         release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
 890         device_unregister(&cdev->device);
 891         return ERR_PTR(result);
 892 }
 893
 894 EXPORT_SYMBOL(thermal_cooling_device_register);
 895
 896 /**
 897  * thermal_cooling_device_unregister - removes the registered thermal cooling device
 898  * @cdev:       the thermal cooling device to remove.
 899  *
 900  * thermal_cooling_device_unregister() must be called when the device is no
 901  * longer needed.
 902  */
 903 void thermal_cooling_device_unregister(struct
 904                                        thermal_cooling_device
 905                                        *cdev)
 906 {
 907         struct thermal_zone_device *tz;
 908         struct thermal_cooling_device *pos = NULL;
 909
 910         if (!cdev)
 911                 return;
 912
 913         mutex_lock(&thermal_list_lock);
 914         list_for_each_entry(pos, &thermal_cdev_list, node)
 915             if (pos == cdev)
 916                 break;
 917         if (pos != cdev) {
 918                 /* thermal cooling device not found */
 919                 mutex_unlock(&thermal_list_lock);
 920                 return;
 921         }
 922         list_del(&cdev->node);
 923         list_for_each_entry(tz, &thermal_tz_list, node) {
 924                 if (!tz->ops->unbind)
 925                         continue;
 926                 tz->ops->unbind(tz, cdev);
 927         }
 928         mutex_unlock(&thermal_list_lock);
 929         if (cdev->type[0])
 930                 device_remove_file(&cdev->device, &dev_attr_cdev_type);
 931         device_remove_file(&cdev->device, &dev_attr_max_state);
 932         device_remove_file(&cdev->device, &dev_attr_cur_state);
 933
 934         release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
 935         device_unregister(&cdev->device);
 936         return;
 937 }
 938
 939 EXPORT_SYMBOL(thermal_cooling_device_unregister);
 940
 941 /**
 942  * thermal_zone_device_update - force an update of a thermal zone's state
 943  * @ttz:        the thermal zone to update
 944  */
 945
 946 void thermal_zone_device_update(struct thermal_zone_device *tz)
 947 {
 948         int count, ret = 0;
 949         long temp, trip_temp;
 950         enum thermal_trip_type trip_type;
 951         struct thermal_cooling_device_instance *instance;
 952         struct thermal_cooling_device *cdev;
 953
 954         mutex_lock(&tz->lock);
 955
 956         tz->ops->get_temp(tz, &temp);
 957
 958         for (count = 0; count < tz->trips; count++) {
 959                 tz->ops->get_trip_type(tz, count, &trip_type);
 960                 tz->ops->get_trip_temp(tz, count, &trip_temp);
 961
 962                 switch (trip_type) {
 963                 case THERMAL_TRIP_CRITICAL:
 964                         if (temp >= trip_temp) {
 965                                 if (tz->ops->notify)
 966                                         ret = tz->ops->notify(tz, count,
 967                                                               trip_type);
 968                                 if (!ret) {
 969                                         printk(KERN_EMERG
 970                                                "Critical temperature reached (%ld C), shutting down.\n",
 971                                                temp/1000);
 972                                         orderly_poweroff(true);
 973                                 }
 974                         }
 975                         break;
 976                 case THERMAL_TRIP_HOT:
 977                         if (temp >= trip_temp)
 978                                 if (tz->ops->notify)
 979                                         tz->ops->notify(tz, count, trip_type);
 980                         break;
 981                 case THERMAL_TRIP_ACTIVE:
 982                         list_for_each_entry(instance, &tz->cooling_devices,
 983                                             node) {
 984                                 if (instance->trip != count)
 985                                         continue;
 986
 987                                 cdev = instance->cdev;
 988
 989                                 if (temp >= trip_temp)
 990                                         cdev->ops->set_cur_state(cdev, 1);
 991                                 else
 992                                         cdev->ops->set_cur_state(cdev, 0);
 993                         }
 994                         break;
 995                 case THERMAL_TRIP_PASSIVE:
 996                         if (temp >= trip_temp || tz->passive)
 997                                 thermal_zone_device_passive(tz, temp,
 998                                                             trip_temp, count);
 999                         break;
1000                 }
1001         }
1002
1003         if (tz->forced_passive)
1004                 thermal_zone_device_passive(tz, temp, tz->forced_passive,
1005                                             THERMAL_TRIPS_NONE);
1006
1007         tz->last_temperature = temp;
1008         if (tz->passive)
1009                 thermal_zone_device_set_polling(tz, tz->passive_delay);
1010         else if (tz->polling_delay)
1011                 thermal_zone_device_set_polling(tz, tz->polling_delay);
1012         mutex_unlock(&tz->lock);
1013 }
1014 EXPORT_SYMBOL(thermal_zone_device_update);
1015
1016 /**
1017  * thermal_zone_device_register - register a new thermal zone device
1018  * @type:       the thermal zone device type
1019  * @trips:      the number of trip points the thermal zone support
1020  * @devdata:    private device data
1021  * @ops:        standard thermal zone device callbacks
1022  * @tc1:        thermal coefficient 1 for passive calculations
1023  * @tc2:        thermal coefficient 2 for passive calculations
1024  * @passive_delay: number of milliseconds to wait between polls when
1025  *                 performing passive cooling
1026  * @polling_delay: number of milliseconds to wait between polls when checking
1027  *                 whether trip points have been crossed (0 for interrupt
1028  *                 driven systems)
1029  *
1030  * thermal_zone_device_unregister() must be called when the device is no
1031  * longer needed. The passive cooling formula uses tc1 and tc2 as described in
1032  * section 11.1.5.1 of the ACPI specification 3.0.
1033  */
1034 struct thermal_zone_device *thermal_zone_device_register(char *type,
1035                                                          int trips,
1036                                                          void *devdata, struct
1037                                                          thermal_zone_device_ops
1038                                                          *ops, int tc1, int
1039                                                          tc2,
1040                                                          int passive_delay,
1041                                                          int polling_delay)
1042 {
1043         struct thermal_zone_device *tz;
1044         struct thermal_cooling_device *pos;
1045         enum thermal_trip_type trip_type;
1046         int result;
1047         int count;
1048         int passive = 0;
1049
1050         if (strlen(type) >= THERMAL_NAME_LENGTH)
1051                 return ERR_PTR(-EINVAL);
1052
1053         if (trips > THERMAL_MAX_TRIPS || trips < 0)
1054                 return ERR_PTR(-EINVAL);
1055
1056         if (!ops || !ops->get_temp)
1057                 return ERR_PTR(-EINVAL);
1058
1059         tz = kzalloc(sizeof(struct thermal_zone_device), GFP_KERNEL);
1060         if (!tz)
1061                 return ERR_PTR(-ENOMEM);
1062
1063         INIT_LIST_HEAD(&tz->cooling_devices);
1064         idr_init(&tz->idr);
1065         mutex_init(&tz->lock);
1066         result = get_idr(&thermal_tz_idr, &thermal_idr_lock, &tz->id);
1067         if (result) {
1068                 kfree(tz);
1069                 return ERR_PTR(result);
1070         }
1071
1072         strcpy(tz->type, type);
1073         tz->ops = ops;
1074         tz->device.class = &thermal_class;
1075         tz->devdata = devdata;
1076         tz->trips = trips;
1077         tz->tc1 = tc1;
1078         tz->tc2 = tc2;
1079         tz->passive_delay = passive_delay;
1080         tz->polling_delay = polling_delay;
1081
1082         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1083         result = device_register(&tz->device);
1084         if (result) {
1085                 release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1086                 kfree(tz);
1087                 return ERR_PTR(result);
1088         }
1089
1090         /* sys I/F */
1091         if (type) {
1092                 result = device_create_file(&tz->device, &dev_attr_type);
1093                 if (result)
1094                         goto unregister;
1095         }
1096
1097         result = device_create_file(&tz->device, &dev_attr_temp);
1098         if (result)
1099                 goto unregister;
1100
1101         if (ops->get_mode) {
1102                 result = device_create_file(&tz->device, &dev_attr_mode);
1103                 if (result)
1104                         goto unregister;
1105         }
1106
1107         for (count = 0; count < trips; count++) {
1108                 TRIP_POINT_ATTR_ADD(&tz->device, count, result);
1109                 if (result)
1110                         goto unregister;
1111                 tz->ops->get_trip_type(tz, count, &trip_type);
1112                 if (trip_type == THERMAL_TRIP_PASSIVE)
1113                         passive = 1;
1114         }
1115
1116         if (!passive)
1117                 result = device_create_file(&tz->device,
1118                                             &dev_attr_passive);
1119
1120         if (result)
1121                 goto unregister;
1122
1123         result = thermal_add_hwmon_sysfs(tz);
1124         if (result)
1125                 goto unregister;
1126
1127         mutex_lock(&thermal_list_lock);
1128         list_add_tail(&tz->node, &thermal_tz_list);
1129         if (ops->bind)
1130                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1131                 result = ops->bind(tz, pos);
1132                 if (result)
1133                         break;
1134                 }
1135         mutex_unlock(&thermal_list_lock);
1136
1137         INIT_DELAYED_WORK(&(tz->poll_queue), thermal_zone_device_check);
1138
1139         thermal_zone_device_update(tz);
1140
1141         if (!result)
1142                 return tz;
1143
1144       unregister:
1145         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1146         device_unregister(&tz->device);
1147         return ERR_PTR(result);
1148 }
1149
1150 EXPORT_SYMBOL(thermal_zone_device_register);
1151
1152 /**
1153  * thermal_device_unregister - removes the registered thermal zone device
1154  * @tz: the thermal zone device to remove
1155  */
1156 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1157 {
1158         struct thermal_cooling_device *cdev;
1159         struct thermal_zone_device *pos = NULL;
1160         int count;
1161
1162         if (!tz)
1163                 return;
1164
1165         mutex_lock(&thermal_list_lock);
1166         list_for_each_entry(pos, &thermal_tz_list, node)
1167             if (pos == tz)
1168                 break;
1169         if (pos != tz) {
1170                 /* thermal zone device not found */
1171                 mutex_unlock(&thermal_list_lock);
1172                 return;
1173         }
1174         list_del(&tz->node);
1175         if (tz->ops->unbind)
1176                 list_for_each_entry(cdev, &thermal_cdev_list, node)
1177                     tz->ops->unbind(tz, cdev);
1178         mutex_unlock(&thermal_list_lock);
1179
1180         thermal_zone_device_set_polling(tz, 0);
1181
1182         if (tz->type[0])
1183                 device_remove_file(&tz->device, &dev_attr_type);
1184         device_remove_file(&tz->device, &dev_attr_temp);
1185         if (tz->ops->get_mode)
1186                 device_remove_file(&tz->device, &dev_attr_mode);
1187
1188         for (count = 0; count < tz->trips; count++)
1189                 TRIP_POINT_ATTR_REMOVE(&tz->device, count);
1190
1191         thermal_remove_hwmon_sysfs(tz);
1192         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1193         idr_destroy(&tz->idr);
1194         mutex_destroy(&tz->lock);
1195         device_unregister(&tz->device);
1196         return;
1197 }
1198
1199 EXPORT_SYMBOL(thermal_zone_device_unregister);
1200
1201 static int __init thermal_init(void)
1202 {
1203         int result = 0;
1204
1205         result = class_register(&thermal_class);
1206         if (result) {
1207                 idr_destroy(&thermal_tz_idr);
1208                 idr_destroy(&thermal_cdev_idr);
1209                 mutex_destroy(&thermal_idr_lock);
1210                 mutex_destroy(&thermal_list_lock);
1211         }
1212         return result;
1213 }
1214
1215 static void __exit thermal_exit(void)
1216 {
1217         class_unregister(&thermal_class);
1218         idr_destroy(&thermal_tz_idr);
1219         idr_destroy(&thermal_cdev_idr);
1220         mutex_destroy(&thermal_idr_lock);
1221         mutex_destroy(&thermal_list_lock);
1222 }
1223
1224 subsys_initcall(thermal_init);
1225 module_exit(thermal_exit);