drivers/acpi/thermal.c

   1 /*
   2  *  acpi_thermal.c - ACPI Thermal Zone Driver ($Revision: 41 $)
   3  *
   4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  *
   7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; either version 2 of the License, or (at
  12  *  your option) any later version.
  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  *  This driver fully implements the ACPI thermal policy as described in the
  26  *  ACPI 2.0 Specification.
  27  *
  28  *  TBD: 1. Implement passive cooling hysteresis.
  29  *       2. Enhance passive cooling (CPU) states/limit interface to support
  30  *          concepts of 'multiple limiters', upper/lower limits, etc.
  31  *
  32  */
  33
  34 #include <linux/kernel.h>
  35 #include <linux/module.h>
  36 #include <linux/init.h>
  37 #include <linux/types.h>
  38 #include <linux/proc_fs.h>
  39 #include <linux/timer.h>
  40 #include <linux/jiffies.h>
  41 #include <linux/kmod.h>
  42 #include <linux/seq_file.h>
  43 #include <asm/uaccess.h>
  44
  45 #include <acpi/acpi_bus.h>
  46 #include <acpi/acpi_drivers.h>
  47
  48 #define ACPI_THERMAL_COMPONENT          0x04000000
  49 #define ACPI_THERMAL_CLASS              "thermal_zone"
  50 #define ACPI_THERMAL_DEVICE_NAME        "Thermal Zone"
  51 #define ACPI_THERMAL_FILE_STATE         "state"
  52 #define ACPI_THERMAL_FILE_TEMPERATURE   "temperature"
  53 #define ACPI_THERMAL_FILE_TRIP_POINTS   "trip_points"
  54 #define ACPI_THERMAL_FILE_COOLING_MODE  "cooling_mode"
  55 #define ACPI_THERMAL_FILE_POLLING_FREQ  "polling_frequency"
  56 #define ACPI_THERMAL_NOTIFY_TEMPERATURE 0x80
  57 #define ACPI_THERMAL_NOTIFY_THRESHOLDS  0x81
  58 #define ACPI_THERMAL_NOTIFY_DEVICES     0x82
  59 #define ACPI_THERMAL_NOTIFY_CRITICAL    0xF0
  60 #define ACPI_THERMAL_NOTIFY_HOT         0xF1
  61 #define ACPI_THERMAL_MODE_ACTIVE        0x00
  62 #define ACPI_THERMAL_PATH_POWEROFF      "/sbin/poweroff"
  63
  64 #define ACPI_THERMAL_MAX_ACTIVE 10
  65 #define ACPI_THERMAL_MAX_LIMIT_STR_LEN 65
  66
  67 #define KELVIN_TO_CELSIUS(t)    (long)(((long)t-2732>=0) ? ((long)t-2732+5)/10 : ((long)t-2732-5)/10)
  68 #define CELSIUS_TO_KELVIN(t)    ((t+273)*10)
  69
  70 #define _COMPONENT              ACPI_THERMAL_COMPONENT
  71 ACPI_MODULE_NAME("thermal");
  72
  73 MODULE_AUTHOR("Paul Diefenbaugh");
  74 MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
  75 MODULE_LICENSE("GPL");
  76
  77 static int tzp;
  78 module_param(tzp, int, 0);
  79 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.\n");
  80
  81 static int acpi_thermal_add(struct acpi_device *device);
  82 static int acpi_thermal_remove(struct acpi_device *device, int type);
  83 static int acpi_thermal_resume(struct acpi_device *device);
  84 static int acpi_thermal_state_open_fs(struct inode *inode, struct file *file);
  85 static int acpi_thermal_temp_open_fs(struct inode *inode, struct file *file);
  86 static int acpi_thermal_trip_open_fs(struct inode *inode, struct file *file);
  87 static int acpi_thermal_cooling_open_fs(struct inode *inode, struct file *file);
  88 static ssize_t acpi_thermal_write_cooling_mode(struct file *,
  89                                                const char __user *, size_t,
  90                                                loff_t *);
  91 static int acpi_thermal_polling_open_fs(struct inode *inode, struct file *file);
  92 static ssize_t acpi_thermal_write_polling(struct file *, const char __user *,
  93                                           size_t, loff_t *);
  94
  95 static struct acpi_driver acpi_thermal_driver = {
  96         .name = "thermal",
  97         .class = ACPI_THERMAL_CLASS,
  98         .ids = ACPI_THERMAL_HID,
  99         .ops = {
 100                 .add = acpi_thermal_add,
 101                 .remove = acpi_thermal_remove,
 102                 .resume = acpi_thermal_resume,
 103                 },
 104 };
 105
 106 struct acpi_thermal_state {
 107         u8 critical:1;
 108         u8 hot:1;
 109         u8 passive:1;
 110         u8 active:1;
 111         u8 reserved:4;
 112         int active_index;
 113 };
 114
 115 struct acpi_thermal_state_flags {
 116         u8 valid:1;
 117         u8 enabled:1;
 118         u8 reserved:6;
 119 };
 120
 121 struct acpi_thermal_critical {
 122         struct acpi_thermal_state_flags flags;
 123         unsigned long temperature;
 124 };
 125
 126 struct acpi_thermal_hot {
 127         struct acpi_thermal_state_flags flags;
 128         unsigned long temperature;
 129 };
 130
 131 struct acpi_thermal_passive {
 132         struct acpi_thermal_state_flags flags;
 133         unsigned long temperature;
 134         unsigned long tc1;
 135         unsigned long tc2;
 136         unsigned long tsp;
 137         struct acpi_handle_list devices;
 138 };
 139
 140 struct acpi_thermal_active {
 141         struct acpi_thermal_state_flags flags;
 142         unsigned long temperature;
 143         struct acpi_handle_list devices;
 144 };
 145
 146 struct acpi_thermal_trips {
 147         struct acpi_thermal_critical critical;
 148         struct acpi_thermal_hot hot;
 149         struct acpi_thermal_passive passive;
 150         struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
 151 };
 152
 153 struct acpi_thermal_flags {
 154         u8 cooling_mode:1;      /* _SCP */
 155         u8 devices:1;           /* _TZD */
 156         u8 reserved:6;
 157 };
 158
 159 struct acpi_thermal {
 160         struct acpi_device * device;
 161         acpi_bus_id name;
 162         unsigned long temperature;
 163         unsigned long last_temperature;
 164         unsigned long polling_frequency;
 165         volatile u8 zombie;
 166         struct acpi_thermal_flags flags;
 167         struct acpi_thermal_state state;
 168         struct acpi_thermal_trips trips;
 169         struct acpi_handle_list devices;
 170         struct timer_list timer;
 171 };
 172
 173 static const struct file_operations acpi_thermal_state_fops = {
 174         .open = acpi_thermal_state_open_fs,
 175         .read = seq_read,
 176         .llseek = seq_lseek,
 177         .release = single_release,
 178 };
 179
 180 static const struct file_operations acpi_thermal_temp_fops = {
 181         .open = acpi_thermal_temp_open_fs,
 182         .read = seq_read,
 183         .llseek = seq_lseek,
 184         .release = single_release,
 185 };
 186
 187 static const struct file_operations acpi_thermal_trip_fops = {
 188         .open = acpi_thermal_trip_open_fs,
 189         .read = seq_read,
 190         .llseek = seq_lseek,
 191         .release = single_release,
 192 };
 193
 194 static const struct file_operations acpi_thermal_cooling_fops = {
 195         .open = acpi_thermal_cooling_open_fs,
 196         .read = seq_read,
 197         .write = acpi_thermal_write_cooling_mode,
 198         .llseek = seq_lseek,
 199         .release = single_release,
 200 };
 201
 202 static const struct file_operations acpi_thermal_polling_fops = {
 203         .open = acpi_thermal_polling_open_fs,
 204         .read = seq_read,
 205         .write = acpi_thermal_write_polling,
 206         .llseek = seq_lseek,
 207         .release = single_release,
 208 };
 209
 210 /* --------------------------------------------------------------------------
 211                              Thermal Zone Management
 212    -------------------------------------------------------------------------- */
 213
 214 static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
 215 {
 216         acpi_status status = AE_OK;
 217
 218
 219         if (!tz)
 220                 return -EINVAL;
 221
 222         tz->last_temperature = tz->temperature;
 223
 224         status =
 225             acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tz->temperature);
 226         if (ACPI_FAILURE(status))
 227                 return -ENODEV;
 228
 229         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Temperature is %lu dK\n",
 230                           tz->temperature));
 231
 232         return 0;
 233 }
 234
 235 static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
 236 {
 237         acpi_status status = AE_OK;
 238
 239
 240         if (!tz)
 241                 return -EINVAL;
 242
 243         status =
 244             acpi_evaluate_integer(tz->device->handle, "_TZP", NULL,
 245                                   &tz->polling_frequency);
 246         if (ACPI_FAILURE(status))
 247                 return -ENODEV;
 248
 249         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Polling frequency is %lu dS\n",
 250                           tz->polling_frequency));
 251
 252         return 0;
 253 }
 254
 255 static int acpi_thermal_set_polling(struct acpi_thermal *tz, int seconds)
 256 {
 257
 258         if (!tz)
 259                 return -EINVAL;
 260
 261         tz->polling_frequency = seconds * 10;   /* Convert value to deci-seconds */
 262
 263         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 264                           "Polling frequency set to %lu seconds\n",
 265                           tz->polling_frequency/10));
 266
 267         return 0;
 268 }
 269
 270 static int acpi_thermal_set_cooling_mode(struct acpi_thermal *tz, int mode)
 271 {
 272         acpi_status status = AE_OK;
 273         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 274         struct acpi_object_list arg_list = { 1, &arg0 };
 275         acpi_handle handle = NULL;
 276
 277
 278         if (!tz)
 279                 return -EINVAL;
 280
 281         status = acpi_get_handle(tz->device->handle, "_SCP", &handle);
 282         if (ACPI_FAILURE(status)) {
 283                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "_SCP not present\n"));
 284                 return -ENODEV;
 285         }
 286
 287         arg0.integer.value = mode;
 288
 289         status = acpi_evaluate_object(handle, NULL, &arg_list, NULL);
 290         if (ACPI_FAILURE(status))
 291                 return -ENODEV;
 292
 293         return 0;
 294 }
 295
 296 static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
 297 {
 298         acpi_status status = AE_OK;
 299         int i = 0;
 300
 301
 302         if (!tz)
 303                 return -EINVAL;
 304
 305         /* Critical Shutdown (required) */
 306
 307         status = acpi_evaluate_integer(tz->device->handle, "_CRT", NULL,
 308                                        &tz->trips.critical.temperature);
 309         if (ACPI_FAILURE(status)) {
 310                 tz->trips.critical.flags.valid = 0;
 311                 ACPI_EXCEPTION((AE_INFO, status, "No critical threshold"));
 312                 return -ENODEV;
 313         } else {
 314                 tz->trips.critical.flags.valid = 1;
 315                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 316                                   "Found critical threshold [%lu]\n",
 317                                   tz->trips.critical.temperature));
 318         }
 319
 320         /* Critical Sleep (optional) */
 321
 322         status =
 323             acpi_evaluate_integer(tz->device->handle, "_HOT", NULL,
 324                                   &tz->trips.hot.temperature);
 325         if (ACPI_FAILURE(status)) {
 326                 tz->trips.hot.flags.valid = 0;
 327                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No hot threshold\n"));
 328         } else {
 329                 tz->trips.hot.flags.valid = 1;
 330                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found hot threshold [%lu]\n",
 331                                   tz->trips.hot.temperature));
 332         }
 333
 334         /* Passive: Processors (optional) */
 335
 336         status =
 337             acpi_evaluate_integer(tz->device->handle, "_PSV", NULL,
 338                                   &tz->trips.passive.temperature);
 339         if (ACPI_FAILURE(status)) {
 340                 tz->trips.passive.flags.valid = 0;
 341                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No passive threshold\n"));
 342         } else {
 343                 tz->trips.passive.flags.valid = 1;
 344
 345                 status =
 346                     acpi_evaluate_integer(tz->device->handle, "_TC1", NULL,
 347                                           &tz->trips.passive.tc1);
 348                 if (ACPI_FAILURE(status))
 349                         tz->trips.passive.flags.valid = 0;
 350
 351                 status =
 352                     acpi_evaluate_integer(tz->device->handle, "_TC2", NULL,
 353                                           &tz->trips.passive.tc2);
 354                 if (ACPI_FAILURE(status))
 355                         tz->trips.passive.flags.valid = 0;
 356
 357                 status =
 358                     acpi_evaluate_integer(tz->device->handle, "_TSP", NULL,
 359                                           &tz->trips.passive.tsp);
 360                 if (ACPI_FAILURE(status))
 361                         tz->trips.passive.flags.valid = 0;
 362
 363                 status =
 364                     acpi_evaluate_reference(tz->device->handle, "_PSL", NULL,
 365                                             &tz->trips.passive.devices);
 366                 if (ACPI_FAILURE(status))
 367                         tz->trips.passive.flags.valid = 0;
 368
 369                 if (!tz->trips.passive.flags.valid)
 370                         printk(KERN_WARNING PREFIX "Invalid passive threshold\n");
 371                 else
 372                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 373                                           "Found passive threshold [%lu]\n",
 374                                           tz->trips.passive.temperature));
 375         }
 376
 377         /* Active: Fans, etc. (optional) */
 378
 379         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 380
 381                 char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
 382
 383                 status =
 384                     acpi_evaluate_integer(tz->device->handle, name, NULL,
 385                                           &tz->trips.active[i].temperature);
 386                 if (ACPI_FAILURE(status))
 387                         break;
 388
 389                 name[2] = 'L';
 390                 status =
 391                     acpi_evaluate_reference(tz->device->handle, name, NULL,
 392                                             &tz->trips.active[i].devices);
 393                 if (ACPI_SUCCESS(status)) {
 394                         tz->trips.active[i].flags.valid = 1;
 395                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 396                                           "Found active threshold [%d]:[%lu]\n",
 397                                           i, tz->trips.active[i].temperature));
 398                 } else
 399                         ACPI_EXCEPTION((AE_INFO, status,
 400                                         "Invalid active threshold [%d]", i));
 401         }
 402
 403         return 0;
 404 }
 405
 406 static int acpi_thermal_get_devices(struct acpi_thermal *tz)
 407 {
 408         acpi_status status = AE_OK;
 409
 410
 411         if (!tz)
 412                 return -EINVAL;
 413
 414         status =
 415             acpi_evaluate_reference(tz->device->handle, "_TZD", NULL, &tz->devices);
 416         if (ACPI_FAILURE(status))
 417                 return -ENODEV;
 418
 419         return 0;
 420 }
 421
 422 static int acpi_thermal_call_usermode(char *path)
 423 {
 424         char *argv[2] = { NULL, NULL };
 425         char *envp[3] = { NULL, NULL, NULL };
 426
 427
 428         if (!path)
 429                 return -EINVAL;
 430
 431         argv[0] = path;
 432
 433         /* minimal command environment */
 434         envp[0] = "HOME=/";
 435         envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 436
 437         call_usermodehelper(argv[0], argv, envp, 0);
 438
 439         return 0;
 440 }
 441
 442 static int acpi_thermal_critical(struct acpi_thermal *tz)
 443 {
 444         if (!tz || !tz->trips.critical.flags.valid)
 445                 return -EINVAL;
 446
 447         if (tz->temperature >= tz->trips.critical.temperature) {
 448                 printk(KERN_WARNING PREFIX "Critical trip point\n");
 449                 tz->trips.critical.flags.enabled = 1;
 450         } else if (tz->trips.critical.flags.enabled)
 451                 tz->trips.critical.flags.enabled = 0;
 452
 453         printk(KERN_EMERG
 454                "Critical temperature reached (%ld C), shutting down.\n",
 455                KELVIN_TO_CELSIUS(tz->temperature));
 456         acpi_bus_generate_event(tz->device, ACPI_THERMAL_NOTIFY_CRITICAL,
 457                                 tz->trips.critical.flags.enabled);
 458
 459         acpi_thermal_call_usermode(ACPI_THERMAL_PATH_POWEROFF);
 460
 461         return 0;
 462 }
 463
 464 static int acpi_thermal_hot(struct acpi_thermal *tz)
 465 {
 466         if (!tz || !tz->trips.hot.flags.valid)
 467                 return -EINVAL;
 468
 469         if (tz->temperature >= tz->trips.hot.temperature) {
 470                 printk(KERN_WARNING PREFIX "Hot trip point\n");
 471                 tz->trips.hot.flags.enabled = 1;
 472         } else if (tz->trips.hot.flags.enabled)
 473                 tz->trips.hot.flags.enabled = 0;
 474
 475         acpi_bus_generate_event(tz->device, ACPI_THERMAL_NOTIFY_HOT,
 476                                 tz->trips.hot.flags.enabled);
 477
 478         /* TBD: Call user-mode "sleep(S4)" function */
 479
 480         return 0;
 481 }
 482
 483 static void acpi_thermal_passive(struct acpi_thermal *tz)
 484 {
 485         int result = 1;
 486         struct acpi_thermal_passive *passive = NULL;
 487         int trend = 0;
 488         int i = 0;
 489
 490
 491         if (!tz || !tz->trips.passive.flags.valid)
 492                 return;
 493
 494         passive = &(tz->trips.passive);
 495
 496         /*
 497          * Above Trip?
 498          * -----------
 499          * Calculate the thermal trend (using the passive cooling equation)
 500          * and modify the performance limit for all passive cooling devices
 501          * accordingly.  Note that we assume symmetry.
 502          */
 503         if (tz->temperature >= passive->temperature) {
 504                 trend =
 505                     (passive->tc1 * (tz->temperature - tz->last_temperature)) +
 506                     (passive->tc2 * (tz->temperature - passive->temperature));
 507                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 508                                   "trend[%d]=(tc1[%lu]*(tmp[%lu]-last[%lu]))+(tc2[%lu]*(tmp[%lu]-psv[%lu]))\n",
 509                                   trend, passive->tc1, tz->temperature,
 510                                   tz->last_temperature, passive->tc2,
 511                                   tz->temperature, passive->temperature));
 512                 passive->flags.enabled = 1;
 513                 /* Heating up? */
 514                 if (trend > 0)
 515                         for (i = 0; i < passive->devices.count; i++)
 516                                 acpi_processor_set_thermal_limit(passive->
 517                                                                  devices.
 518                                                                  handles[i],
 519                                                                  ACPI_PROCESSOR_LIMIT_INCREMENT);
 520                 /* Cooling off? */
 521                 else if (trend < 0) {
 522                         for (i = 0; i < passive->devices.count; i++)
 523                                 /*
 524                                  * assume that we are on highest
 525                                  * freq/lowest thrott and can leave
 526                                  * passive mode, even in error case
 527                                  */
 528                                 if (!acpi_processor_set_thermal_limit
 529                                     (passive->devices.handles[i],
 530                                      ACPI_PROCESSOR_LIMIT_DECREMENT))
 531                                         result = 0;
 532                         /*
 533                          * Leave cooling mode, even if the temp might
 534                          * higher than trip point This is because some
 535                          * machines might have long thermal polling
 536                          * frequencies (tsp) defined. We will fall back
 537                          * into passive mode in next cycle (probably quicker)
 538                          */
 539                         if (result) {
 540                                 passive->flags.enabled = 0;
 541                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 542                                                   "Disabling passive cooling, still above threshold,"
 543                                                   " but we are cooling down\n"));
 544                         }
 545                 }
 546                 return;
 547         }
 548
 549         /*
 550          * Below Trip?
 551          * -----------
 552          * Implement passive cooling hysteresis to slowly increase performance
 553          * and avoid thrashing around the passive trip point.  Note that we
 554          * assume symmetry.
 555          */
 556         if (!passive->flags.enabled)
 557                 return;
 558         for (i = 0; i < passive->devices.count; i++)
 559                 if (!acpi_processor_set_thermal_limit
 560                     (passive->devices.handles[i],
 561                      ACPI_PROCESSOR_LIMIT_DECREMENT))
 562                         result = 0;
 563         if (result) {
 564                 passive->flags.enabled = 0;
 565                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 566                                   "Disabling passive cooling (zone is cool)\n"));
 567         }
 568 }
 569
 570 static void acpi_thermal_active(struct acpi_thermal *tz)
 571 {
 572         int result = 0;
 573         struct acpi_thermal_active *active = NULL;
 574         int i = 0;
 575         int j = 0;
 576         unsigned long maxtemp = 0;
 577
 578
 579         if (!tz)
 580                 return;
 581
 582         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 583                 active = &(tz->trips.active[i]);
 584                 if (!active || !active->flags.valid)
 585                         break;
 586                 if (tz->temperature >= active->temperature) {
 587                         /*
 588                          * Above Threshold?
 589                          * ----------------
 590                          * If not already enabled, turn ON all cooling devices
 591                          * associated with this active threshold.
 592                          */
 593                         if (active->temperature > maxtemp)
 594                                 tz->state.active_index = i;
 595                         maxtemp = active->temperature;
 596                         if (active->flags.enabled)
 597                                 continue;
 598                         for (j = 0; j < active->devices.count; j++) {
 599                                 result =
 600                                     acpi_bus_set_power(active->devices.
 601                                                        handles[j],
 602                                                        ACPI_STATE_D0);
 603                                 if (result) {
 604                                         printk(KERN_WARNING PREFIX
 605                                                       "Unable to turn cooling device [%p] 'on'\n",
 606                                                       active->devices.
 607                                                       handles[j]);
 608                                         continue;
 609                                 }
 610                                 active->flags.enabled = 1;
 611                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 612                                                   "Cooling device [%p] now 'on'\n",
 613                                                   active->devices.handles[j]));
 614                         }
 615                         continue;
 616                 }
 617                 if (!active->flags.enabled)
 618                         continue;
 619                 /*
 620                  * Below Threshold?
 621                  * ----------------
 622                  * Turn OFF all cooling devices associated with this
 623                  * threshold.
 624                  */
 625                 for (j = 0; j < active->devices.count; j++) {
 626                         result = acpi_bus_set_power(active->devices.handles[j],
 627                                                     ACPI_STATE_D3);
 628                         if (result) {
 629                                 printk(KERN_WARNING PREFIX
 630                                               "Unable to turn cooling device [%p] 'off'\n",
 631                                               active->devices.handles[j]);
 632                                 continue;
 633                         }
 634                         active->flags.enabled = 0;
 635                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 636                                           "Cooling device [%p] now 'off'\n",
 637                                           active->devices.handles[j]));
 638                 }
 639         }
 640 }
 641
 642 static void acpi_thermal_check(void *context);
 643
 644 static void acpi_thermal_run(unsigned long data)
 645 {
 646         struct acpi_thermal *tz = (struct acpi_thermal *)data;
 647         if (!tz->zombie)
 648                 acpi_os_execute(OSL_GPE_HANDLER, acpi_thermal_check, (void *)data);
 649 }
 650
 651 static void acpi_thermal_check(void *data)
 652 {
 653         int result = 0;
 654         struct acpi_thermal *tz = data;
 655         unsigned long sleep_time = 0;
 656         int i = 0;
 657         struct acpi_thermal_state state;
 658
 659
 660         if (!tz) {
 661                 printk(KERN_ERR PREFIX "Invalid (NULL) context\n");
 662                 return;
 663         }
 664
 665         state = tz->state;
 666
 667         result = acpi_thermal_get_temperature(tz);
 668         if (result)
 669                 return;
 670
 671         memset(&tz->state, 0, sizeof(tz->state));
 672
 673         /*
 674          * Check Trip Points
 675          * -----------------
 676          * Compare the current temperature to the trip point values to see
 677          * if we've entered one of the thermal policy states.  Note that
 678          * this function determines when a state is entered, but the
 679          * individual policy decides when it is exited (e.g. hysteresis).
 680          */
 681         if (tz->trips.critical.flags.valid)
 682                 state.critical |=
 683                     (tz->temperature >= tz->trips.critical.temperature);
 684         if (tz->trips.hot.flags.valid)
 685                 state.hot |= (tz->temperature >= tz->trips.hot.temperature);
 686         if (tz->trips.passive.flags.valid)
 687                 state.passive |=
 688                     (tz->temperature >= tz->trips.passive.temperature);
 689         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
 690                 if (tz->trips.active[i].flags.valid)
 691                         state.active |=
 692                             (tz->temperature >=
 693                              tz->trips.active[i].temperature);
 694
 695         /*
 696          * Invoke Policy
 697          * -------------
 698          * Separated from the above check to allow individual policy to
 699          * determine when to exit a given state.
 700          */
 701         if (state.critical)
 702                 acpi_thermal_critical(tz);
 703         if (state.hot)
 704                 acpi_thermal_hot(tz);
 705         if (state.passive)
 706                 acpi_thermal_passive(tz);
 707         if (state.active)
 708                 acpi_thermal_active(tz);
 709
 710         /*
 711          * Calculate State
 712          * ---------------
 713          * Again, separated from the above two to allow independent policy
 714          * decisions.
 715          */
 716         tz->state.critical = tz->trips.critical.flags.enabled;
 717         tz->state.hot = tz->trips.hot.flags.enabled;
 718         tz->state.passive = tz->trips.passive.flags.enabled;
 719         tz->state.active = 0;
 720         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
 721                 tz->state.active |= tz->trips.active[i].flags.enabled;
 722
 723         /*
 724          * Calculate Sleep Time
 725          * --------------------
 726          * If we're in the passive state, use _TSP's value.  Otherwise
 727          * use the default polling frequency (e.g. _TZP).  If no polling
 728          * frequency is specified then we'll wait forever (at least until
 729          * a thermal event occurs).  Note that _TSP and _TZD values are
 730          * given in 1/10th seconds (we must covert to milliseconds).
 731          */
 732         if (tz->state.passive)
 733                 sleep_time = tz->trips.passive.tsp * 100;
 734         else if (tz->polling_frequency > 0)
 735                 sleep_time = tz->polling_frequency * 100;
 736
 737         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s: temperature[%lu] sleep[%lu]\n",
 738                           tz->name, tz->temperature, sleep_time));
 739
 740         /*
 741          * Schedule Next Poll
 742          * ------------------
 743          */
 744         if (!sleep_time) {
 745                 if (timer_pending(&(tz->timer)))
 746                         del_timer(&(tz->timer));
 747         } else {
 748                 if (timer_pending(&(tz->timer)))
 749                         mod_timer(&(tz->timer),
 750                                         jiffies + (HZ * sleep_time) / 1000);
 751                 else {
 752                         tz->timer.data = (unsigned long)tz;
 753                         tz->timer.function = acpi_thermal_run;
 754                         tz->timer.expires = jiffies + (HZ * sleep_time) / 1000;
 755                         add_timer(&(tz->timer));
 756                 }
 757         }
 758
 759         return;
 760 }
 761
 762 /* --------------------------------------------------------------------------
 763                               FS Interface (/proc)
 764    -------------------------------------------------------------------------- */
 765
 766 static struct proc_dir_entry *acpi_thermal_dir;
 767
 768 static int acpi_thermal_state_seq_show(struct seq_file *seq, void *offset)
 769 {
 770         struct acpi_thermal *tz = seq->private;
 771
 772
 773         if (!tz)
 774                 goto end;
 775
 776         seq_puts(seq, "state:                   ");
 777
 778         if (!tz->state.critical && !tz->state.hot && !tz->state.passive
 779             && !tz->state.active)
 780                 seq_puts(seq, "ok\n");
 781         else {
 782                 if (tz->state.critical)
 783                         seq_puts(seq, "critical ");
 784                 if (tz->state.hot)
 785                         seq_puts(seq, "hot ");
 786                 if (tz->state.passive)
 787                         seq_puts(seq, "passive ");
 788                 if (tz->state.active)
 789                         seq_printf(seq, "active[%d]", tz->state.active_index);
 790                 seq_puts(seq, "\n");
 791         }
 792
 793       end:
 794         return 0;
 795 }
 796
 797 static int acpi_thermal_state_open_fs(struct inode *inode, struct file *file)
 798 {
 799         return single_open(file, acpi_thermal_state_seq_show, PDE(inode)->data);
 800 }
 801
 802 static int acpi_thermal_temp_seq_show(struct seq_file *seq, void *offset)
 803 {
 804         int result = 0;
 805         struct acpi_thermal *tz = seq->private;
 806
 807
 808         if (!tz)
 809                 goto end;
 810
 811         result = acpi_thermal_get_temperature(tz);
 812         if (result)
 813                 goto end;
 814
 815         seq_printf(seq, "temperature:             %ld C\n",
 816                    KELVIN_TO_CELSIUS(tz->temperature));
 817
 818       end:
 819         return 0;
 820 }
 821
 822 static int acpi_thermal_temp_open_fs(struct inode *inode, struct file *file)
 823 {
 824         return single_open(file, acpi_thermal_temp_seq_show, PDE(inode)->data);
 825 }
 826
 827 static int acpi_thermal_trip_seq_show(struct seq_file *seq, void *offset)
 828 {
 829         struct acpi_thermal *tz = seq->private;
 830         struct acpi_device *device;
 831         acpi_status status;
 832
 833         int i = 0;
 834         int j = 0;
 835
 836
 837         if (!tz)
 838                 goto end;
 839
 840         if (tz->trips.critical.flags.valid)
 841                 seq_printf(seq, "critical (S5):           %ld C\n",
 842                            KELVIN_TO_CELSIUS(tz->trips.critical.temperature));
 843
 844         if (tz->trips.hot.flags.valid)
 845                 seq_printf(seq, "hot (S4):                %ld C\n",
 846                            KELVIN_TO_CELSIUS(tz->trips.hot.temperature));
 847
 848         if (tz->trips.passive.flags.valid) {
 849                 seq_printf(seq,
 850                            "passive:                 %ld C: tc1=%lu tc2=%lu tsp=%lu devices=",
 851                            KELVIN_TO_CELSIUS(tz->trips.passive.temperature),
 852                            tz->trips.passive.tc1, tz->trips.passive.tc2,
 853                            tz->trips.passive.tsp);
 854                 for (j = 0; j < tz->trips.passive.devices.count; j++) {
 855                         status = acpi_bus_get_device(tz->trips.passive.devices.
 856                                                      handles[j], &device);
 857                         seq_printf(seq, "%4.4s ", status ? "" :
 858                                    acpi_device_bid(device));
 859                 }
 860                 seq_puts(seq, "\n");
 861         }
 862
 863         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 864                 if (!(tz->trips.active[i].flags.valid))
 865                         break;
 866                 seq_printf(seq, "active[%d]:               %ld C: devices=",
 867                            i,
 868                            KELVIN_TO_CELSIUS(tz->trips.active[i].temperature));
 869                 for (j = 0; j < tz->trips.active[i].devices.count; j++){
 870                         status = acpi_bus_get_device(tz->trips.active[i].
 871                                                      devices.handles[j],
 872                                                      &device);
 873                         seq_printf(seq, "%4.4s ", status ? "" :
 874                                    acpi_device_bid(device));
 875                 }
 876                 seq_puts(seq, "\n");
 877         }
 878
 879       end:
 880         return 0;
 881 }
 882
 883 static int acpi_thermal_trip_open_fs(struct inode *inode, struct file *file)
 884 {
 885         return single_open(file, acpi_thermal_trip_seq_show, PDE(inode)->data);
 886 }
 887
 888 static int acpi_thermal_cooling_seq_show(struct seq_file *seq, void *offset)
 889 {
 890         struct acpi_thermal *tz = seq->private;
 891
 892
 893         if (!tz)
 894                 goto end;
 895
 896         if (!tz->flags.cooling_mode)
 897                 seq_puts(seq, "<setting not supported>\n");
 898         else
 899                 seq_puts(seq, "0 - Active; 1 - Passive\n");
 900
 901       end:
 902         return 0;
 903 }
 904
 905 static int acpi_thermal_cooling_open_fs(struct inode *inode, struct file *file)
 906 {
 907         return single_open(file, acpi_thermal_cooling_seq_show,
 908                            PDE(inode)->data);
 909 }
 910
 911 static ssize_t
 912 acpi_thermal_write_cooling_mode(struct file *file,
 913                                 const char __user * buffer,
 914                                 size_t count, loff_t * ppos)
 915 {
 916         struct seq_file *m = file->private_data;
 917         struct acpi_thermal *tz = m->private;
 918         int result = 0;
 919         char mode_string[12] = { '\0' };
 920
 921
 922         if (!tz || (count > sizeof(mode_string) - 1))
 923                 return -EINVAL;
 924
 925         if (!tz->flags.cooling_mode)
 926                 return -ENODEV;
 927
 928         if (copy_from_user(mode_string, buffer, count))
 929                 return -EFAULT;
 930
 931         mode_string[count] = '\0';
 932
 933         result = acpi_thermal_set_cooling_mode(tz,
 934                                                simple_strtoul(mode_string, NULL,
 935                                                               0));
 936         if (result)
 937                 return result;
 938
 939         acpi_thermal_check(tz);
 940
 941         return count;
 942 }
 943
 944 static int acpi_thermal_polling_seq_show(struct seq_file *seq, void *offset)
 945 {
 946         struct acpi_thermal *tz = seq->private;
 947
 948
 949         if (!tz)
 950                 goto end;
 951
 952         if (!tz->polling_frequency) {
 953                 seq_puts(seq, "<polling disabled>\n");
 954                 goto end;
 955         }
 956
 957         seq_printf(seq, "polling frequency:       %lu seconds\n",
 958                    (tz->polling_frequency / 10));
 959
 960       end:
 961         return 0;
 962 }
 963
 964 static int acpi_thermal_polling_open_fs(struct inode *inode, struct file *file)
 965 {
 966         return single_open(file, acpi_thermal_polling_seq_show,
 967                            PDE(inode)->data);
 968 }
 969
 970 static ssize_t
 971 acpi_thermal_write_polling(struct file *file,
 972                            const char __user * buffer,
 973                            size_t count, loff_t * ppos)
 974 {
 975         struct seq_file *m = file->private_data;
 976         struct acpi_thermal *tz = m->private;
 977         int result = 0;
 978         char polling_string[12] = { '\0' };
 979         int seconds = 0;
 980
 981
 982         if (!tz || (count > sizeof(polling_string) - 1))
 983                 return -EINVAL;
 984
 985         if (copy_from_user(polling_string, buffer, count))
 986                 return -EFAULT;
 987
 988         polling_string[count] = '\0';
 989
 990         seconds = simple_strtoul(polling_string, NULL, 0);
 991
 992         result = acpi_thermal_set_polling(tz, seconds);
 993         if (result)
 994                 return result;
 995
 996         acpi_thermal_check(tz);
 997
 998         return count;
 999 }
1000
1001 static int acpi_thermal_add_fs(struct acpi_device *device)
1002 {
1003         struct proc_dir_entry *entry = NULL;
1004
1005
1006         if (!acpi_device_dir(device)) {
1007                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
1008                                                      acpi_thermal_dir);
1009                 if (!acpi_device_dir(device))
1010                         return -ENODEV;
1011                 acpi_device_dir(device)->owner = THIS_MODULE;
1012         }
1013
1014         /* 'state' [R] */
1015         entry = create_proc_entry(ACPI_THERMAL_FILE_STATE,
1016                                   S_IRUGO, acpi_device_dir(device));
1017         if (!entry)
1018                 return -ENODEV;
1019         else {
1020                 entry->proc_fops = &acpi_thermal_state_fops;
1021                 entry->data = acpi_driver_data(device);
1022                 entry->owner = THIS_MODULE;
1023         }
1024
1025         /* 'temperature' [R] */
1026         entry = create_proc_entry(ACPI_THERMAL_FILE_TEMPERATURE,
1027                                   S_IRUGO, acpi_device_dir(device));
1028         if (!entry)
1029                 return -ENODEV;
1030         else {
1031                 entry->proc_fops = &acpi_thermal_temp_fops;
1032                 entry->data = acpi_driver_data(device);
1033                 entry->owner = THIS_MODULE;
1034         }
1035
1036         /* 'trip_points' [R/W] */
1037         entry = create_proc_entry(ACPI_THERMAL_FILE_TRIP_POINTS,
1038                                   S_IFREG | S_IRUGO | S_IWUSR,
1039                                   acpi_device_dir(device));
1040         if (!entry)
1041                 return -ENODEV;
1042         else {
1043                 entry->proc_fops = &acpi_thermal_trip_fops;
1044                 entry->data = acpi_driver_data(device);
1045                 entry->owner = THIS_MODULE;
1046         }
1047
1048         /* 'cooling_mode' [R/W] */
1049         entry = create_proc_entry(ACPI_THERMAL_FILE_COOLING_MODE,
1050                                   S_IFREG | S_IRUGO | S_IWUSR,
1051                                   acpi_device_dir(device));
1052         if (!entry)
1053                 return -ENODEV;
1054         else {
1055                 entry->proc_fops = &acpi_thermal_cooling_fops;
1056                 entry->data = acpi_driver_data(device);
1057                 entry->owner = THIS_MODULE;
1058         }
1059
1060         /* 'polling_frequency' [R/W] */
1061         entry = create_proc_entry(ACPI_THERMAL_FILE_POLLING_FREQ,
1062                                   S_IFREG | S_IRUGO | S_IWUSR,
1063                                   acpi_device_dir(device));
1064         if (!entry)
1065                 return -ENODEV;
1066         else {
1067                 entry->proc_fops = &acpi_thermal_polling_fops;
1068                 entry->data = acpi_driver_data(device);
1069                 entry->owner = THIS_MODULE;
1070         }
1071
1072         return 0;
1073 }
1074
1075 static int acpi_thermal_remove_fs(struct acpi_device *device)
1076 {
1077
1078         if (acpi_device_dir(device)) {
1079                 remove_proc_entry(ACPI_THERMAL_FILE_POLLING_FREQ,
1080                                   acpi_device_dir(device));
1081                 remove_proc_entry(ACPI_THERMAL_FILE_COOLING_MODE,
1082                                   acpi_device_dir(device));
1083                 remove_proc_entry(ACPI_THERMAL_FILE_TRIP_POINTS,
1084                                   acpi_device_dir(device));
1085                 remove_proc_entry(ACPI_THERMAL_FILE_TEMPERATURE,
1086                                   acpi_device_dir(device));
1087                 remove_proc_entry(ACPI_THERMAL_FILE_STATE,
1088                                   acpi_device_dir(device));
1089                 remove_proc_entry(acpi_device_bid(device), acpi_thermal_dir);
1090                 acpi_device_dir(device) = NULL;
1091         }
1092
1093         return 0;
1094 }
1095
1096 /* --------------------------------------------------------------------------
1097                                  Driver Interface
1098    -------------------------------------------------------------------------- */
1099
1100 static void acpi_thermal_notify(acpi_handle handle, u32 event, void *data)
1101 {
1102         struct acpi_thermal *tz = data;
1103         struct acpi_device *device = NULL;
1104
1105
1106         if (!tz)
1107                 return;
1108
1109         device = tz->device;
1110
1111         switch (event) {
1112         case ACPI_THERMAL_NOTIFY_TEMPERATURE:
1113                 acpi_thermal_check(tz);
1114                 break;
1115         case ACPI_THERMAL_NOTIFY_THRESHOLDS:
1116                 acpi_thermal_get_trip_points(tz);
1117                 acpi_thermal_check(tz);
1118                 acpi_bus_generate_event(device, event, 0);
1119                 break;
1120         case ACPI_THERMAL_NOTIFY_DEVICES:
1121                 if (tz->flags.devices)
1122                         acpi_thermal_get_devices(tz);
1123                 acpi_bus_generate_event(device, event, 0);
1124                 break;
1125         default:
1126                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1127                                   "Unsupported event [0x%x]\n", event));
1128                 break;
1129         }
1130
1131         return;
1132 }
1133
1134 static int acpi_thermal_get_info(struct acpi_thermal *tz)
1135 {
1136         int result = 0;
1137
1138
1139         if (!tz)
1140                 return -EINVAL;
1141
1142         /* Get temperature [_TMP] (required) */
1143         result = acpi_thermal_get_temperature(tz);
1144         if (result)
1145                 return result;
1146
1147         /* Get trip points [_CRT, _PSV, etc.] (required) */
1148         result = acpi_thermal_get_trip_points(tz);
1149         if (result)
1150                 return result;
1151
1152         /* Set the cooling mode [_SCP] to active cooling (default) */
1153         result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
1154         if (!result)
1155                 tz->flags.cooling_mode = 1;
1156
1157         /* Get default polling frequency [_TZP] (optional) */
1158         if (tzp)
1159                 tz->polling_frequency = tzp;
1160         else
1161                 acpi_thermal_get_polling_frequency(tz);
1162
1163         /* Get devices in this thermal zone [_TZD] (optional) */
1164         result = acpi_thermal_get_devices(tz);
1165         if (!result)
1166                 tz->flags.devices = 1;
1167
1168         return 0;
1169 }
1170
1171 static int acpi_thermal_add(struct acpi_device *device)
1172 {
1173         int result = 0;
1174         acpi_status status = AE_OK;
1175         struct acpi_thermal *tz = NULL;
1176
1177
1178         if (!device)
1179                 return -EINVAL;
1180
1181         tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
1182         if (!tz)
1183                 return -ENOMEM;
1184
1185         tz->device = device;
1186         strcpy(tz->name, device->pnp.bus_id);
1187         strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
1188         strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
1189         acpi_driver_data(device) = tz;
1190
1191         result = acpi_thermal_get_info(tz);
1192         if (result)
1193                 goto end;
1194
1195         result = acpi_thermal_add_fs(device);
1196         if (result)
1197                 goto end;
1198
1199         init_timer(&tz->timer);
1200
1201         acpi_thermal_check(tz);
1202
1203         status = acpi_install_notify_handler(device->handle,
1204                                              ACPI_DEVICE_NOTIFY,
1205                                              acpi_thermal_notify, tz);
1206         if (ACPI_FAILURE(status)) {
1207                 result = -ENODEV;
1208                 goto end;
1209         }
1210
1211         printk(KERN_INFO PREFIX "%s [%s] (%ld C)\n",
1212                acpi_device_name(device), acpi_device_bid(device),
1213                KELVIN_TO_CELSIUS(tz->temperature));
1214
1215       end:
1216         if (result) {
1217                 acpi_thermal_remove_fs(device);
1218                 kfree(tz);
1219         }
1220
1221         return result;
1222 }
1223
1224 static int acpi_thermal_remove(struct acpi_device *device, int type)
1225 {
1226         acpi_status status = AE_OK;
1227         struct acpi_thermal *tz = NULL;
1228
1229
1230         if (!device || !acpi_driver_data(device))
1231                 return -EINVAL;
1232
1233         tz = acpi_driver_data(device);
1234
1235         /* avoid timer adding new defer task */
1236         tz->zombie = 1;
1237         /* wait for running timer (on other CPUs) finish */
1238         del_timer_sync(&(tz->timer));
1239         /* synchronize deferred task */
1240         acpi_os_wait_events_complete(NULL);
1241         /* deferred task may reinsert timer */
1242         del_timer_sync(&(tz->timer));
1243
1244         status = acpi_remove_notify_handler(device->handle,
1245                                             ACPI_DEVICE_NOTIFY,
1246                                             acpi_thermal_notify);
1247
1248         /* Terminate policy */
1249         if (tz->trips.passive.flags.valid && tz->trips.passive.flags.enabled) {
1250                 tz->trips.passive.flags.enabled = 0;
1251                 acpi_thermal_passive(tz);
1252         }
1253         if (tz->trips.active[0].flags.valid
1254             && tz->trips.active[0].flags.enabled) {
1255                 tz->trips.active[0].flags.enabled = 0;
1256                 acpi_thermal_active(tz);
1257         }
1258
1259         acpi_thermal_remove_fs(device);
1260
1261         kfree(tz);
1262         return 0;
1263 }
1264
1265 static int acpi_thermal_resume(struct acpi_device *device)
1266 {
1267         struct acpi_thermal *tz = NULL;
1268         int i, j, power_state, result;
1269
1270
1271         if (!device || !acpi_driver_data(device))
1272                 return -EINVAL;
1273
1274         tz = acpi_driver_data(device);
1275
1276         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1277                 if (!(&tz->trips.active[i]))
1278                         break;
1279                 if (!tz->trips.active[i].flags.valid)
1280                         break;
1281                 tz->trips.active[i].flags.enabled = 1;
1282                 for (j = 0; j < tz->trips.active[i].devices.count; j++) {
1283                         result = acpi_bus_get_power(tz->trips.active[i].devices.
1284                             handles[j], &power_state);
1285                         if (result || (power_state != ACPI_STATE_D0)) {
1286                                 tz->trips.active[i].flags.enabled = 0;
1287                                 break;
1288                         }
1289                 }
1290                 tz->state.active |= tz->trips.active[i].flags.enabled;
1291         }
1292
1293         acpi_thermal_check(tz);
1294
1295         return AE_OK;
1296 }
1297
1298 static int __init acpi_thermal_init(void)
1299 {
1300         int result = 0;
1301
1302
1303         acpi_thermal_dir = proc_mkdir(ACPI_THERMAL_CLASS, acpi_root_dir);
1304         if (!acpi_thermal_dir)
1305                 return -ENODEV;
1306         acpi_thermal_dir->owner = THIS_MODULE;
1307
1308         result = acpi_bus_register_driver(&acpi_thermal_driver);
1309         if (result < 0) {
1310                 remove_proc_entry(ACPI_THERMAL_CLASS, acpi_root_dir);
1311                 return -ENODEV;
1312         }
1313
1314         return 0;
1315 }
1316
1317 static void __exit acpi_thermal_exit(void)
1318 {
1319
1320         acpi_bus_unregister_driver(&acpi_thermal_driver);
1321
1322         remove_proc_entry(ACPI_THERMAL_CLASS, acpi_root_dir);
1323
1324         return;
1325 }
1326
1327 module_init(acpi_thermal_init);
1328 module_exit(acpi_thermal_exit);