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/slab.h>
  30 #include <linux/kdev_t.h>
  31 #include <linux/idr.h>
  32 #include <linux/thermal.h>
  33 #include <linux/spinlock.h>
  34 #include <linux/reboot.h>
  35
  36 MODULE_AUTHOR("Zhang Rui");
  37 MODULE_DESCRIPTION("Generic thermal management sysfs support");
  38 MODULE_LICENSE("GPL");
  39
  40 #define PREFIX "Thermal: "
  41
  42 struct thermal_cooling_device_instance {
  43         int id;
  44         char name[THERMAL_NAME_LENGTH];
  45         struct thermal_zone_device *tz;
  46         struct thermal_cooling_device *cdev;
  47         int trip;
  48         char attr_name[THERMAL_NAME_LENGTH];
  49         struct device_attribute attr;
  50         struct list_head node;
  51 };
  52
  53 static DEFINE_IDR(thermal_tz_idr);
  54 static DEFINE_IDR(thermal_cdev_idr);
  55 static DEFINE_MUTEX(thermal_idr_lock);
  56
  57 static LIST_HEAD(thermal_tz_list);
  58 static LIST_HEAD(thermal_cdev_list);
  59 static DEFINE_MUTEX(thermal_list_lock);
  60
  61 static int get_idr(struct idr *idr, struct mutex *lock, int *id)
  62 {
  63         int err;
  64
  65       again:
  66         if (unlikely(idr_pre_get(idr, GFP_KERNEL) == 0))
  67                 return -ENOMEM;
  68
  69         if (lock)
  70                 mutex_lock(lock);
  71         err = idr_get_new(idr, NULL, id);
  72         if (lock)
  73                 mutex_unlock(lock);
  74         if (unlikely(err == -EAGAIN))
  75                 goto again;
  76         else if (unlikely(err))
  77                 return err;
  78
  79         *id = *id & MAX_ID_MASK;
  80         return 0;
  81 }
  82
  83 static void release_idr(struct idr *idr, struct mutex *lock, int id)
  84 {
  85         if (lock)
  86                 mutex_lock(lock);
  87         idr_remove(idr, id);
  88         if (lock)
  89                 mutex_unlock(lock);
  90 }
  91
  92 /* sys I/F for thermal zone */
  93
  94 #define to_thermal_zone(_dev) \
  95         container_of(_dev, struct thermal_zone_device, device)
  96
  97 static ssize_t
  98 type_show(struct device *dev, struct device_attribute *attr, char *buf)
  99 {
 100         struct thermal_zone_device *tz = to_thermal_zone(dev);
 101
 102         return sprintf(buf, "%s\n", tz->type);
 103 }
 104
 105 static ssize_t
 106 temp_show(struct device *dev, struct device_attribute *attr, char *buf)
 107 {
 108         struct thermal_zone_device *tz = to_thermal_zone(dev);
 109         long temperature;
 110         int ret;
 111
 112         if (!tz->ops->get_temp)
 113                 return -EPERM;
 114
 115         ret = tz->ops->get_temp(tz, &temperature);
 116
 117         if (ret)
 118                 return ret;
 119
 120         return sprintf(buf, "%ld\n", temperature);
 121 }
 122
 123 static ssize_t
 124 mode_show(struct device *dev, struct device_attribute *attr, char *buf)
 125 {
 126         struct thermal_zone_device *tz = to_thermal_zone(dev);
 127         enum thermal_device_mode mode;
 128         int result;
 129
 130         if (!tz->ops->get_mode)
 131                 return -EPERM;
 132
 133         result = tz->ops->get_mode(tz, &mode);
 134         if (result)
 135                 return result;
 136
 137         return sprintf(buf, "%s\n", mode == THERMAL_DEVICE_ENABLED ? "enabled"
 138                        : "disabled");
 139 }
 140
 141 static ssize_t
 142 mode_store(struct device *dev, struct device_attribute *attr,
 143            const char *buf, size_t count)
 144 {
 145         struct thermal_zone_device *tz = to_thermal_zone(dev);
 146         int result;
 147
 148         if (!tz->ops->set_mode)
 149                 return -EPERM;
 150
 151         if (!strncmp(buf, "enabled", sizeof("enabled")))
 152                 result = tz->ops->set_mode(tz, THERMAL_DEVICE_ENABLED);
 153         else if (!strncmp(buf, "disabled", sizeof("disabled")))
 154                 result = tz->ops->set_mode(tz, THERMAL_DEVICE_DISABLED);
 155         else
 156                 result = -EINVAL;
 157
 158         if (result)
 159                 return result;
 160
 161         return count;
 162 }
 163
 164 static ssize_t
 165 trip_point_type_show(struct device *dev, struct device_attribute *attr,
 166                      char *buf)
 167 {
 168         struct thermal_zone_device *tz = to_thermal_zone(dev);
 169         enum thermal_trip_type type;
 170         int trip, result;
 171
 172         if (!tz->ops->get_trip_type)
 173                 return -EPERM;
 174
 175         if (!sscanf(attr->attr.name, "trip_point_%d_type", &trip))
 176                 return -EINVAL;
 177
 178         result = tz->ops->get_trip_type(tz, trip, &type);
 179         if (result)
 180                 return result;
 181
 182         switch (type) {
 183         case THERMAL_TRIP_CRITICAL:
 184                 return sprintf(buf, "critical\n");
 185         case THERMAL_TRIP_HOT:
 186                 return sprintf(buf, "hot\n");
 187         case THERMAL_TRIP_PASSIVE:
 188                 return sprintf(buf, "passive\n");
 189         case THERMAL_TRIP_ACTIVE:
 190                 return sprintf(buf, "active\n");
 191         default:
 192                 return sprintf(buf, "unknown\n");
 193         }
 194 }
 195
 196 static ssize_t
 197 trip_point_temp_show(struct device *dev, struct device_attribute *attr,
 198                      char *buf)
 199 {
 200         struct thermal_zone_device *tz = to_thermal_zone(dev);
 201         int trip, ret;
 202         long temperature;
 203
 204         if (!tz->ops->get_trip_temp)
 205                 return -EPERM;
 206
 207         if (!sscanf(attr->attr.name, "trip_point_%d_temp", &trip))
 208                 return -EINVAL;
 209
 210         ret = tz->ops->get_trip_temp(tz, trip, &temperature);
 211
 212         if (ret)
 213                 return ret;
 214
 215         return sprintf(buf, "%ld\n", temperature);
 216 }
 217
 218 static ssize_t
 219 passive_store(struct device *dev, struct device_attribute *attr,
 220                     const char *buf, size_t count)
 221 {
 222         struct thermal_zone_device *tz = to_thermal_zone(dev);
 223         struct thermal_cooling_device *cdev = NULL;
 224         int state;
 225
 226         if (!sscanf(buf, "%d\n", &state))
 227                 return -EINVAL;
 228
 229         /* sanity check: values below 1000 millicelcius don't make sense
 230          * and can cause the system to go into a thermal heart attack
 231          */
 232         if (state && state < 1000)
 233                 return -EINVAL;
 234
 235         if (state && !tz->forced_passive) {
 236                 mutex_lock(&thermal_list_lock);
 237                 list_for_each_entry(cdev, &thermal_cdev_list, node) {
 238                         if (!strncmp("Processor", cdev->type,
 239                                      sizeof("Processor")))
 240                                 thermal_zone_bind_cooling_device(tz,
 241                                                                  THERMAL_TRIPS_NONE,
 242                                                                  cdev);
 243                 }
 244                 mutex_unlock(&thermal_list_lock);
 245                 if (!tz->passive_delay)
 246                         tz->passive_delay = 1000;
 247         } else if (!state && tz->forced_passive) {
 248                 mutex_lock(&thermal_list_lock);
 249                 list_for_each_entry(cdev, &thermal_cdev_list, node) {
 250                         if (!strncmp("Processor", cdev->type,
 251                                      sizeof("Processor")))
 252                                 thermal_zone_unbind_cooling_device(tz,
 253                                                                    THERMAL_TRIPS_NONE,
 254                                                                    cdev);
 255                 }
 256                 mutex_unlock(&thermal_list_lock);
 257                 tz->passive_delay = 0;
 258         }
 259
 260         tz->tc1 = 1;
 261         tz->tc2 = 1;
 262
 263         tz->forced_passive = state;
 264
 265         thermal_zone_device_update(tz);
 266
 267         return count;
 268 }
 269
 270 static ssize_t
 271 passive_show(struct device *dev, struct device_attribute *attr,
 272                    char *buf)
 273 {
 274         struct thermal_zone_device *tz = to_thermal_zone(dev);
 275
 276         return sprintf(buf, "%d\n", tz->forced_passive);
 277 }
 278
 279 static DEVICE_ATTR(type, 0444, type_show, NULL);
 280 static DEVICE_ATTR(temp, 0444, temp_show, NULL);
 281 static DEVICE_ATTR(mode, 0644, mode_show, mode_store);
 282 static DEVICE_ATTR(passive, S_IRUGO | S_IWUSR, passive_show, \
 283                    passive_store);
 284
 285 static struct device_attribute trip_point_attrs[] = {
 286         __ATTR(trip_point_0_type, 0444, trip_point_type_show, NULL),
 287         __ATTR(trip_point_0_temp, 0444, trip_point_temp_show, NULL),
 288         __ATTR(trip_point_1_type, 0444, trip_point_type_show, NULL),
 289         __ATTR(trip_point_1_temp, 0444, trip_point_temp_show, NULL),
 290         __ATTR(trip_point_2_type, 0444, trip_point_type_show, NULL),
 291         __ATTR(trip_point_2_temp, 0444, trip_point_temp_show, NULL),
 292         __ATTR(trip_point_3_type, 0444, trip_point_type_show, NULL),
 293         __ATTR(trip_point_3_temp, 0444, trip_point_temp_show, NULL),
 294         __ATTR(trip_point_4_type, 0444, trip_point_type_show, NULL),
 295         __ATTR(trip_point_4_temp, 0444, trip_point_temp_show, NULL),
 296         __ATTR(trip_point_5_type, 0444, trip_point_type_show, NULL),
 297         __ATTR(trip_point_5_temp, 0444, trip_point_temp_show, NULL),
 298         __ATTR(trip_point_6_type, 0444, trip_point_type_show, NULL),
 299         __ATTR(trip_point_6_temp, 0444, trip_point_temp_show, NULL),
 300         __ATTR(trip_point_7_type, 0444, trip_point_type_show, NULL),
 301         __ATTR(trip_point_7_temp, 0444, trip_point_temp_show, NULL),
 302         __ATTR(trip_point_8_type, 0444, trip_point_type_show, NULL),
 303         __ATTR(trip_point_8_temp, 0444, trip_point_temp_show, NULL),
 304         __ATTR(trip_point_9_type, 0444, trip_point_type_show, NULL),
 305         __ATTR(trip_point_9_temp, 0444, trip_point_temp_show, NULL),
 306         __ATTR(trip_point_10_type, 0444, trip_point_type_show, NULL),
 307         __ATTR(trip_point_10_temp, 0444, trip_point_temp_show, NULL),
 308         __ATTR(trip_point_11_type, 0444, trip_point_type_show, NULL),
 309         __ATTR(trip_point_11_temp, 0444, trip_point_temp_show, NULL),
 310 };
 311
 312 #define TRIP_POINT_ATTR_ADD(_dev, _index, result)     \
 313 do {    \
 314         result = device_create_file(_dev,       \
 315                                 &trip_point_attrs[_index * 2]); \
 316         if (result)     \
 317                 break;  \
 318         result = device_create_file(_dev,       \
 319                         &trip_point_attrs[_index * 2 + 1]);     \
 320 } while (0)
 321
 322 #define TRIP_POINT_ATTR_REMOVE(_dev, _index)    \
 323 do {    \
 324         device_remove_file(_dev, &trip_point_attrs[_index * 2]);        \
 325         device_remove_file(_dev, &trip_point_attrs[_index * 2 + 1]);    \
 326 } while (0)
 327
 328 /* sys I/F for cooling device */
 329 #define to_cooling_device(_dev) \
 330         container_of(_dev, struct thermal_cooling_device, device)
 331
 332 static ssize_t
 333 thermal_cooling_device_type_show(struct device *dev,
 334                                  struct device_attribute *attr, char *buf)
 335 {
 336         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 337
 338         return sprintf(buf, "%s\n", cdev->type);
 339 }
 340
 341 static ssize_t
 342 thermal_cooling_device_max_state_show(struct device *dev,
 343                                       struct device_attribute *attr, char *buf)
 344 {
 345         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 346         unsigned long state;
 347         int ret;
 348
 349         ret = cdev->ops->get_max_state(cdev, &state);
 350         if (ret)
 351                 return ret;
 352         return sprintf(buf, "%ld\n", state);
 353 }
 354
 355 static ssize_t
 356 thermal_cooling_device_cur_state_show(struct device *dev,
 357                                       struct device_attribute *attr, char *buf)
 358 {
 359         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 360         unsigned long state;
 361         int ret;
 362
 363         ret = cdev->ops->get_cur_state(cdev, &state);
 364         if (ret)
 365                 return ret;
 366         return sprintf(buf, "%ld\n", state);
 367 }
 368
 369 static ssize_t
 370 thermal_cooling_device_cur_state_store(struct device *dev,
 371                                        struct device_attribute *attr,
 372                                        const char *buf, size_t count)
 373 {
 374         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 375         unsigned long state;
 376         int result;
 377
 378         if (!sscanf(buf, "%ld\n", &state))
 379                 return -EINVAL;
 380
 381         if ((long)state < 0)
 382                 return -EINVAL;
 383
 384         result = cdev->ops->set_cur_state(cdev, state);
 385         if (result)
 386                 return result;
 387         return count;
 388 }
 389
 390 static struct device_attribute dev_attr_cdev_type =
 391 __ATTR(type, 0444, thermal_cooling_device_type_show, NULL);
 392 static DEVICE_ATTR(max_state, 0444,
 393                    thermal_cooling_device_max_state_show, NULL);
 394 static DEVICE_ATTR(cur_state, 0644,
 395                    thermal_cooling_device_cur_state_show,
 396                    thermal_cooling_device_cur_state_store);
 397
 398 static ssize_t
 399 thermal_cooling_device_trip_point_show(struct device *dev,
 400                                        struct device_attribute *attr, char *buf)
 401 {
 402         struct thermal_cooling_device_instance *instance;
 403
 404         instance =
 405             container_of(attr, struct thermal_cooling_device_instance, attr);
 406
 407         if (instance->trip == THERMAL_TRIPS_NONE)
 408                 return sprintf(buf, "-1\n");
 409         else
 410                 return sprintf(buf, "%d\n", instance->trip);
 411 }
 412
 413 /* Device management */
 414
 415 #if defined(CONFIG_THERMAL_HWMON)
 416
 417 /* hwmon sys I/F */
 418 #include <linux/hwmon.h>
 419 static LIST_HEAD(thermal_hwmon_list);
 420
 421 static ssize_t
 422 name_show(struct device *dev, struct device_attribute *attr, char *buf)
 423 {
 424         struct thermal_hwmon_device *hwmon = dev_get_drvdata(dev);
 425         return sprintf(buf, "%s\n", hwmon->type);
 426 }
 427 static DEVICE_ATTR(name, 0444, name_show, NULL);
 428
 429 static ssize_t
 430 temp_input_show(struct device *dev, struct device_attribute *attr, char *buf)
 431 {
 432         long temperature;
 433         int ret;
 434         struct thermal_hwmon_attr *hwmon_attr
 435                         = container_of(attr, struct thermal_hwmon_attr, attr);
 436         struct thermal_zone_device *tz
 437                         = container_of(hwmon_attr, struct thermal_zone_device,
 438                                        temp_input);
 439
 440         ret = tz->ops->get_temp(tz, &temperature);
 441
 442         if (ret)
 443                 return ret;
 444
 445         return sprintf(buf, "%ld\n", temperature);
 446 }
 447
 448 static ssize_t
 449 temp_crit_show(struct device *dev, struct device_attribute *attr,
 450                 char *buf)
 451 {
 452         struct thermal_hwmon_attr *hwmon_attr
 453                         = container_of(attr, struct thermal_hwmon_attr, attr);
 454         struct thermal_zone_device *tz
 455                         = container_of(hwmon_attr, struct thermal_zone_device,
 456                                        temp_crit);
 457         long temperature;
 458         int ret;
 459
 460         ret = tz->ops->get_trip_temp(tz, 0, &temperature);
 461         if (ret)
 462                 return ret;
 463
 464         return sprintf(buf, "%ld\n", temperature);
 465 }
 466
 467
 468 static int
 469 thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
 470 {
 471         struct thermal_hwmon_device *hwmon;
 472         int new_hwmon_device = 1;
 473         int result;
 474
 475         mutex_lock(&thermal_list_lock);
 476         list_for_each_entry(hwmon, &thermal_hwmon_list, node)
 477                 if (!strcmp(hwmon->type, tz->type)) {
 478                         new_hwmon_device = 0;
 479                         mutex_unlock(&thermal_list_lock);
 480                         goto register_sys_interface;
 481                 }
 482         mutex_unlock(&thermal_list_lock);
 483
 484         hwmon = kzalloc(sizeof(struct thermal_hwmon_device), GFP_KERNEL);
 485         if (!hwmon)
 486                 return -ENOMEM;
 487
 488         INIT_LIST_HEAD(&hwmon->tz_list);
 489         strlcpy(hwmon->type, tz->type, THERMAL_NAME_LENGTH);
 490         hwmon->device = hwmon_device_register(NULL);
 491         if (IS_ERR(hwmon->device)) {
 492                 result = PTR_ERR(hwmon->device);
 493                 goto free_mem;
 494         }
 495         dev_set_drvdata(hwmon->device, hwmon);
 496         result = device_create_file(hwmon->device, &dev_attr_name);
 497         if (result)
 498                 goto unregister_hwmon_device;
 499
 500  register_sys_interface:
 501         tz->hwmon = hwmon;
 502         hwmon->count++;
 503
 504         snprintf(tz->temp_input.name, THERMAL_NAME_LENGTH,
 505                  "temp%d_input", hwmon->count);
 506         tz->temp_input.attr.attr.name = tz->temp_input.name;
 507         tz->temp_input.attr.attr.mode = 0444;
 508         tz->temp_input.attr.show = temp_input_show;
 509         result = device_create_file(hwmon->device, &tz->temp_input.attr);
 510         if (result)
 511                 goto unregister_hwmon_device;
 512
 513         if (tz->ops->get_crit_temp) {
 514                 unsigned long temperature;
 515                 if (!tz->ops->get_crit_temp(tz, &temperature)) {
 516                         snprintf(tz->temp_crit.name, THERMAL_NAME_LENGTH,
 517                                 "temp%d_crit", hwmon->count);
 518                         tz->temp_crit.attr.attr.name = tz->temp_crit.name;
 519                         tz->temp_crit.attr.attr.mode = 0444;
 520                         tz->temp_crit.attr.show = temp_crit_show;
 521                         result = device_create_file(hwmon->device,
 522                                                     &tz->temp_crit.attr);
 523                         if (result)
 524                                 goto unregister_hwmon_device;
 525                 }
 526         }
 527
 528         mutex_lock(&thermal_list_lock);
 529         if (new_hwmon_device)
 530                 list_add_tail(&hwmon->node, &thermal_hwmon_list);
 531         list_add_tail(&tz->hwmon_node, &hwmon->tz_list);
 532         mutex_unlock(&thermal_list_lock);
 533
 534         return 0;
 535
 536  unregister_hwmon_device:
 537         device_remove_file(hwmon->device, &tz->temp_crit.attr);
 538         device_remove_file(hwmon->device, &tz->temp_input.attr);
 539         if (new_hwmon_device) {
 540                 device_remove_file(hwmon->device, &dev_attr_name);
 541                 hwmon_device_unregister(hwmon->device);
 542         }
 543  free_mem:
 544         if (new_hwmon_device)
 545                 kfree(hwmon);
 546
 547         return result;
 548 }
 549
 550 static void
 551 thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
 552 {
 553         struct thermal_hwmon_device *hwmon = tz->hwmon;
 554
 555         tz->hwmon = NULL;
 556         device_remove_file(hwmon->device, &tz->temp_input.attr);
 557         device_remove_file(hwmon->device, &tz->temp_crit.attr);
 558
 559         mutex_lock(&thermal_list_lock);
 560         list_del(&tz->hwmon_node);
 561         if (!list_empty(&hwmon->tz_list)) {
 562                 mutex_unlock(&thermal_list_lock);
 563                 return;
 564         }
 565         list_del(&hwmon->node);
 566         mutex_unlock(&thermal_list_lock);
 567
 568         device_remove_file(hwmon->device, &dev_attr_name);
 569         hwmon_device_unregister(hwmon->device);
 570         kfree(hwmon);
 571 }
 572 #else
 573 static int
 574 thermal_add_hwmon_sysfs(struct thermal_zone_device *tz)
 575 {
 576         return 0;
 577 }
 578
 579 static void
 580 thermal_remove_hwmon_sysfs(struct thermal_zone_device *tz)
 581 {
 582 }
 583 #endif
 584
 585 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 586                                             int delay)
 587 {
 588         cancel_delayed_work(&(tz->poll_queue));
 589
 590         if (!delay)
 591                 return;
 592
 593         if (delay > 1000)
 594                 schedule_delayed_work(&(tz->poll_queue),
 595                                       round_jiffies(msecs_to_jiffies(delay)));
 596         else
 597                 schedule_delayed_work(&(tz->poll_queue),
 598                                       msecs_to_jiffies(delay));
 599 }
 600
 601 static void thermal_zone_device_passive(struct thermal_zone_device *tz,
 602                                         int temp, int trip_temp, int trip)
 603 {
 604         int trend = 0;
 605         struct thermal_cooling_device_instance *instance;
 606         struct thermal_cooling_device *cdev;
 607         long state, max_state;
 608
 609         /*
 610          * Above Trip?
 611          * -----------
 612          * Calculate the thermal trend (using the passive cooling equation)
 613          * and modify the performance limit for all passive cooling devices
 614          * accordingly.  Note that we assume symmetry.
 615          */
 616         if (temp >= trip_temp) {
 617                 tz->passive = true;
 618
 619                 trend = (tz->tc1 * (temp - tz->last_temperature)) +
 620                         (tz->tc2 * (temp - trip_temp));
 621
 622                 /* Heating up? */
 623                 if (trend > 0) {
 624                         list_for_each_entry(instance, &tz->cooling_devices,
 625                                             node) {
 626                                 if (instance->trip != trip)
 627                                         continue;
 628                                 cdev = instance->cdev;
 629                                 cdev->ops->get_cur_state(cdev, &state);
 630                                 cdev->ops->get_max_state(cdev, &max_state);
 631                                 if (state++ < max_state)
 632                                         cdev->ops->set_cur_state(cdev, state);
 633                         }
 634                 } else if (trend < 0) { /* Cooling off? */
 635                         list_for_each_entry(instance, &tz->cooling_devices,
 636                                             node) {
 637                                 if (instance->trip != trip)
 638                                         continue;
 639                                 cdev = instance->cdev;
 640                                 cdev->ops->get_cur_state(cdev, &state);
 641                                 cdev->ops->get_max_state(cdev, &max_state);
 642                                 if (state > 0)
 643                                         cdev->ops->set_cur_state(cdev, --state);
 644                         }
 645                 }
 646                 return;
 647         }
 648
 649         /*
 650          * Below Trip?
 651          * -----------
 652          * Implement passive cooling hysteresis to slowly increase performance
 653          * and avoid thrashing around the passive trip point.  Note that we
 654          * assume symmetry.
 655          */
 656         list_for_each_entry(instance, &tz->cooling_devices, node) {
 657                 if (instance->trip != trip)
 658                         continue;
 659                 cdev = instance->cdev;
 660                 cdev->ops->get_cur_state(cdev, &state);
 661                 cdev->ops->get_max_state(cdev, &max_state);
 662                 if (state > 0)
 663                         cdev->ops->set_cur_state(cdev, --state);
 664                 if (state == 0)
 665                         tz->passive = false;
 666         }
 667 }
 668
 669 static void thermal_zone_device_check(struct work_struct *work)
 670 {
 671         struct thermal_zone_device *tz = container_of(work, struct
 672                                                       thermal_zone_device,
 673                                                       poll_queue.work);
 674         thermal_zone_device_update(tz);
 675 }
 676
 677 /**
 678  * thermal_zone_bind_cooling_device - bind a cooling device to a thermal zone
 679  * @tz:         thermal zone device
 680  * @trip:       indicates which trip point the cooling devices is
 681  *              associated with in this thermal zone.
 682  * @cdev:       thermal cooling device
 683  *
 684  * This function is usually called in the thermal zone device .bind callback.
 685  */
 686 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 687                                      int trip,
 688                                      struct thermal_cooling_device *cdev)
 689 {
 690         struct thermal_cooling_device_instance *dev;
 691         struct thermal_cooling_device_instance *pos;
 692         struct thermal_zone_device *pos1;
 693         struct thermal_cooling_device *pos2;
 694         int result;
 695
 696         if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 697                 return -EINVAL;
 698
 699         list_for_each_entry(pos1, &thermal_tz_list, node) {
 700                 if (pos1 == tz)
 701                         break;
 702         }
 703         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 704                 if (pos2 == cdev)
 705                         break;
 706         }
 707
 708         if (tz != pos1 || cdev != pos2)
 709                 return -EINVAL;
 710
 711         dev =
 712             kzalloc(sizeof(struct thermal_cooling_device_instance), GFP_KERNEL);
 713         if (!dev)
 714                 return -ENOMEM;
 715         dev->tz = tz;
 716         dev->cdev = cdev;
 717         dev->trip = trip;
 718         result = get_idr(&tz->idr, &tz->lock, &dev->id);
 719         if (result)
 720                 goto free_mem;
 721
 722         sprintf(dev->name, "cdev%d", dev->id);
 723         result =
 724             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 725         if (result)
 726                 goto release_idr;
 727
 728         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 729         dev->attr.attr.name = dev->attr_name;
 730         dev->attr.attr.mode = 0444;
 731         dev->attr.show = thermal_cooling_device_trip_point_show;
 732         result = device_create_file(&tz->device, &dev->attr);
 733         if (result)
 734                 goto remove_symbol_link;
 735
 736         mutex_lock(&tz->lock);
 737         list_for_each_entry(pos, &tz->cooling_devices, node)
 738             if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 739                 result = -EEXIST;
 740                 break;
 741         }
 742         if (!result)
 743                 list_add_tail(&dev->node, &tz->cooling_devices);
 744         mutex_unlock(&tz->lock);
 745
 746         if (!result)
 747                 return 0;
 748
 749         device_remove_file(&tz->device, &dev->attr);
 750       remove_symbol_link:
 751         sysfs_remove_link(&tz->device.kobj, dev->name);
 752       release_idr:
 753         release_idr(&tz->idr, &tz->lock, dev->id);
 754       free_mem:
 755         kfree(dev);
 756         return result;
 757 }
 758
 759 EXPORT_SYMBOL(thermal_zone_bind_cooling_device);
 760
 761 /**
 762  * thermal_zone_unbind_cooling_device - unbind a cooling device from a thermal zone
 763  * @tz:         thermal zone device
 764  * @trip:       indicates which trip point the cooling devices is
 765  *              associated with in this thermal zone.
 766  * @cdev:       thermal cooling device
 767  *
 768  * This function is usually called in the thermal zone device .unbind callback.
 769  */
 770 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 771                                        int trip,
 772                                        struct thermal_cooling_device *cdev)
 773 {
 774         struct thermal_cooling_device_instance *pos, *next;
 775
 776         mutex_lock(&tz->lock);
 777         list_for_each_entry_safe(pos, next, &tz->cooling_devices, node) {
 778                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 779                         list_del(&pos->node);
 780                         mutex_unlock(&tz->lock);
 781                         goto unbind;
 782                 }
 783         }
 784         mutex_unlock(&tz->lock);
 785
 786         return -ENODEV;
 787
 788       unbind:
 789         device_remove_file(&tz->device, &pos->attr);
 790         sysfs_remove_link(&tz->device.kobj, pos->name);
 791         release_idr(&tz->idr, &tz->lock, pos->id);
 792         kfree(pos);
 793         return 0;
 794 }
 795
 796 EXPORT_SYMBOL(thermal_zone_unbind_cooling_device);
 797
 798 static void thermal_release(struct device *dev)
 799 {
 800         struct thermal_zone_device *tz;
 801         struct thermal_cooling_device *cdev;
 802
 803         if (!strncmp(dev_name(dev), "thermal_zone", sizeof "thermal_zone" - 1)) {
 804                 tz = to_thermal_zone(dev);
 805                 kfree(tz);
 806         } else {
 807                 cdev = to_cooling_device(dev);
 808                 kfree(cdev);
 809         }
 810 }
 811
 812 static struct class thermal_class = {
 813         .name = "thermal",
 814         .dev_release = thermal_release,
 815 };
 816
 817 /**
 818  * thermal_cooling_device_register - register a new thermal cooling device
 819  * @type:       the thermal cooling device type.
 820  * @devdata:    device private data.
 821  * @ops:                standard thermal cooling devices callbacks.
 822  */
 823 struct thermal_cooling_device *thermal_cooling_device_register(char *type,
 824                                                                void *devdata,
 825                                                                struct
 826                                                                thermal_cooling_device_ops
 827                                                                *ops)
 828 {
 829         struct thermal_cooling_device *cdev;
 830         struct thermal_zone_device *pos;
 831         int result;
 832
 833         if (strlen(type) >= THERMAL_NAME_LENGTH)
 834                 return ERR_PTR(-EINVAL);
 835
 836         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 837             !ops->set_cur_state)
 838                 return ERR_PTR(-EINVAL);
 839
 840         cdev = kzalloc(sizeof(struct thermal_cooling_device), GFP_KERNEL);
 841         if (!cdev)
 842                 return ERR_PTR(-ENOMEM);
 843
 844         result = get_idr(&thermal_cdev_idr, &thermal_idr_lock, &cdev->id);
 845         if (result) {
 846                 kfree(cdev);
 847                 return ERR_PTR(result);
 848         }
 849
 850         strcpy(cdev->type, type);
 851         cdev->ops = ops;
 852         cdev->device.class = &thermal_class;
 853         cdev->devdata = devdata;
 854         dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 855         result = device_register(&cdev->device);
 856         if (result) {
 857                 release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
 858                 kfree(cdev);
 859                 return ERR_PTR(result);
 860         }
 861
 862         /* sys I/F */
 863         if (type) {
 864                 result = device_create_file(&cdev->device, &dev_attr_cdev_type);
 865                 if (result)
 866                         goto unregister;
 867         }
 868
 869         result = device_create_file(&cdev->device, &dev_attr_max_state);
 870         if (result)
 871                 goto unregister;
 872
 873         result = device_create_file(&cdev->device, &dev_attr_cur_state);
 874         if (result)
 875                 goto unregister;
 876
 877         mutex_lock(&thermal_list_lock);
 878         list_add(&cdev->node, &thermal_cdev_list);
 879         list_for_each_entry(pos, &thermal_tz_list, node) {
 880                 if (!pos->ops->bind)
 881                         continue;
 882                 result = pos->ops->bind(pos, cdev);
 883                 if (result)
 884                         break;
 885
 886         }
 887         mutex_unlock(&thermal_list_lock);
 888
 889         if (!result)
 890                 return cdev;
 891
 892       unregister:
 893         release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
 894         device_unregister(&cdev->device);
 895         return ERR_PTR(result);
 896 }
 897
 898 EXPORT_SYMBOL(thermal_cooling_device_register);
 899
 900 /**
 901  * thermal_cooling_device_unregister - removes the registered thermal cooling device
 902  * @cdev:       the thermal cooling device to remove.
 903  *
 904  * thermal_cooling_device_unregister() must be called when the device is no
 905  * longer needed.
 906  */
 907 void thermal_cooling_device_unregister(struct
 908                                        thermal_cooling_device
 909                                        *cdev)
 910 {
 911         struct thermal_zone_device *tz;
 912         struct thermal_cooling_device *pos = NULL;
 913
 914         if (!cdev)
 915                 return;
 916
 917         mutex_lock(&thermal_list_lock);
 918         list_for_each_entry(pos, &thermal_cdev_list, node)
 919             if (pos == cdev)
 920                 break;
 921         if (pos != cdev) {
 922                 /* thermal cooling device not found */
 923                 mutex_unlock(&thermal_list_lock);
 924                 return;
 925         }
 926         list_del(&cdev->node);
 927         list_for_each_entry(tz, &thermal_tz_list, node) {
 928                 if (!tz->ops->unbind)
 929                         continue;
 930                 tz->ops->unbind(tz, cdev);
 931         }
 932         mutex_unlock(&thermal_list_lock);
 933         if (cdev->type[0])
 934                 device_remove_file(&cdev->device, &dev_attr_cdev_type);
 935         device_remove_file(&cdev->device, &dev_attr_max_state);
 936         device_remove_file(&cdev->device, &dev_attr_cur_state);
 937
 938         release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
 939         device_unregister(&cdev->device);
 940         return;
 941 }
 942
 943 EXPORT_SYMBOL(thermal_cooling_device_unregister);
 944
 945 /**
 946  * thermal_zone_device_update - force an update of a thermal zone's state
 947  * @ttz:        the thermal zone to update
 948  */
 949
 950 void thermal_zone_device_update(struct thermal_zone_device *tz)
 951 {
 952         int count, ret = 0;
 953         long temp, trip_temp;
 954         enum thermal_trip_type trip_type;
 955         struct thermal_cooling_device_instance *instance;
 956         struct thermal_cooling_device *cdev;
 957
 958         mutex_lock(&tz->lock);
 959
 960         if (tz->ops->get_temp(tz, &temp)) {
 961                 /* get_temp failed - retry it later */
 962                 printk(KERN_WARNING PREFIX "failed to read out thermal zone "
 963                        "%d\n", tz->id);
 964                 goto leave;
 965         }
 966
 967         for (count = 0; count < tz->trips; count++) {
 968                 tz->ops->get_trip_type(tz, count, &trip_type);
 969                 tz->ops->get_trip_temp(tz, count, &trip_temp);
 970
 971                 switch (trip_type) {
 972                 case THERMAL_TRIP_CRITICAL:
 973                         if (temp >= trip_temp) {
 974                                 if (tz->ops->notify)
 975                                         ret = tz->ops->notify(tz, count,
 976                                                               trip_type);
 977                                 if (!ret) {
 978                                         printk(KERN_EMERG
 979                                                "Critical temperature reached (%ld C), shutting down.\n",
 980                                                temp/1000);
 981                                         orderly_poweroff(true);
 982                                 }
 983                         }
 984                         break;
 985                 case THERMAL_TRIP_HOT:
 986                         if (temp >= trip_temp)
 987                                 if (tz->ops->notify)
 988                                         tz->ops->notify(tz, count, trip_type);
 989                         break;
 990                 case THERMAL_TRIP_ACTIVE:
 991                         list_for_each_entry(instance, &tz->cooling_devices,
 992                                             node) {
 993                                 if (instance->trip != count)
 994                                         continue;
 995
 996                                 cdev = instance->cdev;
 997
 998                                 if (temp >= trip_temp)
 999                                         cdev->ops->set_cur_state(cdev, 1);
1000                                 else
1001                                         cdev->ops->set_cur_state(cdev, 0);
1002                         }
1003                         break;
1004                 case THERMAL_TRIP_PASSIVE:
1005                         if (temp >= trip_temp || tz->passive)
1006                                 thermal_zone_device_passive(tz, temp,
1007                                                             trip_temp, count);
1008                         break;
1009                 }
1010         }
1011
1012         if (tz->forced_passive)
1013                 thermal_zone_device_passive(tz, temp, tz->forced_passive,
1014                                             THERMAL_TRIPS_NONE);
1015
1016         tz->last_temperature = temp;
1017
1018       leave:
1019         if (tz->passive)
1020                 thermal_zone_device_set_polling(tz, tz->passive_delay);
1021         else if (tz->polling_delay)
1022                 thermal_zone_device_set_polling(tz, tz->polling_delay);
1023         else
1024                 thermal_zone_device_set_polling(tz, 0);
1025         mutex_unlock(&tz->lock);
1026 }
1027 EXPORT_SYMBOL(thermal_zone_device_update);
1028
1029 /**
1030  * thermal_zone_device_register - register a new thermal zone device
1031  * @type:       the thermal zone device type
1032  * @trips:      the number of trip points the thermal zone support
1033  * @devdata:    private device data
1034  * @ops:        standard thermal zone device callbacks
1035  * @tc1:        thermal coefficient 1 for passive calculations
1036  * @tc2:        thermal coefficient 2 for passive calculations
1037  * @passive_delay: number of milliseconds to wait between polls when
1038  *                 performing passive cooling
1039  * @polling_delay: number of milliseconds to wait between polls when checking
1040  *                 whether trip points have been crossed (0 for interrupt
1041  *                 driven systems)
1042  *
1043  * thermal_zone_device_unregister() must be called when the device is no
1044  * longer needed. The passive cooling formula uses tc1 and tc2 as described in
1045  * section 11.1.5.1 of the ACPI specification 3.0.
1046  */
1047 struct thermal_zone_device *thermal_zone_device_register(char *type,
1048                                                          int trips,
1049                                                          void *devdata, struct
1050                                                          thermal_zone_device_ops
1051                                                          *ops, int tc1, int
1052                                                          tc2,
1053                                                          int passive_delay,
1054                                                          int polling_delay)
1055 {
1056         struct thermal_zone_device *tz;
1057         struct thermal_cooling_device *pos;
1058         enum thermal_trip_type trip_type;
1059         int result;
1060         int count;
1061         int passive = 0;
1062
1063         if (strlen(type) >= THERMAL_NAME_LENGTH)
1064                 return ERR_PTR(-EINVAL);
1065
1066         if (trips > THERMAL_MAX_TRIPS || trips < 0)
1067                 return ERR_PTR(-EINVAL);
1068
1069         if (!ops || !ops->get_temp)
1070                 return ERR_PTR(-EINVAL);
1071
1072         tz = kzalloc(sizeof(struct thermal_zone_device), GFP_KERNEL);
1073         if (!tz)
1074                 return ERR_PTR(-ENOMEM);
1075
1076         INIT_LIST_HEAD(&tz->cooling_devices);
1077         idr_init(&tz->idr);
1078         mutex_init(&tz->lock);
1079         result = get_idr(&thermal_tz_idr, &thermal_idr_lock, &tz->id);
1080         if (result) {
1081                 kfree(tz);
1082                 return ERR_PTR(result);
1083         }
1084
1085         strcpy(tz->type, type);
1086         tz->ops = ops;
1087         tz->device.class = &thermal_class;
1088         tz->devdata = devdata;
1089         tz->trips = trips;
1090         tz->tc1 = tc1;
1091         tz->tc2 = tc2;
1092         tz->passive_delay = passive_delay;
1093         tz->polling_delay = polling_delay;
1094
1095         dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1096         result = device_register(&tz->device);
1097         if (result) {
1098                 release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1099                 kfree(tz);
1100                 return ERR_PTR(result);
1101         }
1102
1103         /* sys I/F */
1104         if (type) {
1105                 result = device_create_file(&tz->device, &dev_attr_type);
1106                 if (result)
1107                         goto unregister;
1108         }
1109
1110         result = device_create_file(&tz->device, &dev_attr_temp);
1111         if (result)
1112                 goto unregister;
1113
1114         if (ops->get_mode) {
1115                 result = device_create_file(&tz->device, &dev_attr_mode);
1116                 if (result)
1117                         goto unregister;
1118         }
1119
1120         for (count = 0; count < trips; count++) {
1121                 TRIP_POINT_ATTR_ADD(&tz->device, count, result);
1122                 if (result)
1123                         goto unregister;
1124                 tz->ops->get_trip_type(tz, count, &trip_type);
1125                 if (trip_type == THERMAL_TRIP_PASSIVE)
1126                         passive = 1;
1127         }
1128
1129         if (!passive)
1130                 result = device_create_file(&tz->device,
1131                                             &dev_attr_passive);
1132
1133         if (result)
1134                 goto unregister;
1135
1136         result = thermal_add_hwmon_sysfs(tz);
1137         if (result)
1138                 goto unregister;
1139
1140         mutex_lock(&thermal_list_lock);
1141         list_add_tail(&tz->node, &thermal_tz_list);
1142         if (ops->bind)
1143                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1144                 result = ops->bind(tz, pos);
1145                 if (result)
1146                         break;
1147                 }
1148         mutex_unlock(&thermal_list_lock);
1149
1150         INIT_DELAYED_WORK(&(tz->poll_queue), thermal_zone_device_check);
1151
1152         thermal_zone_device_update(tz);
1153
1154         if (!result)
1155                 return tz;
1156
1157       unregister:
1158         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1159         device_unregister(&tz->device);
1160         return ERR_PTR(result);
1161 }
1162
1163 EXPORT_SYMBOL(thermal_zone_device_register);
1164
1165 /**
1166  * thermal_device_unregister - removes the registered thermal zone device
1167  * @tz: the thermal zone device to remove
1168  */
1169 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1170 {
1171         struct thermal_cooling_device *cdev;
1172         struct thermal_zone_device *pos = NULL;
1173         int count;
1174
1175         if (!tz)
1176                 return;
1177
1178         mutex_lock(&thermal_list_lock);
1179         list_for_each_entry(pos, &thermal_tz_list, node)
1180             if (pos == tz)
1181                 break;
1182         if (pos != tz) {
1183                 /* thermal zone device not found */
1184                 mutex_unlock(&thermal_list_lock);
1185                 return;
1186         }
1187         list_del(&tz->node);
1188         if (tz->ops->unbind)
1189                 list_for_each_entry(cdev, &thermal_cdev_list, node)
1190                     tz->ops->unbind(tz, cdev);
1191         mutex_unlock(&thermal_list_lock);
1192
1193         thermal_zone_device_set_polling(tz, 0);
1194
1195         if (tz->type[0])
1196                 device_remove_file(&tz->device, &dev_attr_type);
1197         device_remove_file(&tz->device, &dev_attr_temp);
1198         if (tz->ops->get_mode)
1199                 device_remove_file(&tz->device, &dev_attr_mode);
1200
1201         for (count = 0; count < tz->trips; count++)
1202                 TRIP_POINT_ATTR_REMOVE(&tz->device, count);
1203
1204         thermal_remove_hwmon_sysfs(tz);
1205         release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1206         idr_destroy(&tz->idr);
1207         mutex_destroy(&tz->lock);
1208         device_unregister(&tz->device);
1209         return;
1210 }
1211
1212 EXPORT_SYMBOL(thermal_zone_device_unregister);
1213
1214 static int __init thermal_init(void)
1215 {
1216         int result = 0;
1217
1218         result = class_register(&thermal_class);
1219         if (result) {
1220                 idr_destroy(&thermal_tz_idr);
1221                 idr_destroy(&thermal_cdev_idr);
1222                 mutex_destroy(&thermal_idr_lock);
1223                 mutex_destroy(&thermal_list_lock);
1224         }
1225         return result;
1226 }
1227
1228 static void __exit thermal_exit(void)
1229 {
1230         class_unregister(&thermal_class);
1231         idr_destroy(&thermal_tz_idr);
1232         idr_destroy(&thermal_cdev_idr);
1233         mutex_destroy(&thermal_idr_lock);
1234         mutex_destroy(&thermal_list_lock);
1235 }
1236
1237 subsys_initcall(thermal_init);
1238 module_exit(thermal_exit);