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 <linux/reboot.h>
  44 #include <asm/uaccess.h>
  45
  46 #include <acpi/acpi_bus.h>
  47 #include <acpi/acpi_drivers.h>
  48
  49 #define ACPI_THERMAL_COMPONENT          0x04000000
  50 #define ACPI_THERMAL_CLASS              "thermal_zone"
  51 #define ACPI_THERMAL_DEVICE_NAME        "Thermal Zone"
  52 #define ACPI_THERMAL_FILE_STATE         "state"
  53 #define ACPI_THERMAL_FILE_TEMPERATURE   "temperature"
  54 #define ACPI_THERMAL_FILE_TRIP_POINTS   "trip_points"
  55 #define ACPI_THERMAL_FILE_COOLING_MODE  "cooling_mode"
  56 #define ACPI_THERMAL_FILE_POLLING_FREQ  "polling_frequency"
  57 #define ACPI_THERMAL_NOTIFY_TEMPERATURE 0x80
  58 #define ACPI_THERMAL_NOTIFY_THRESHOLDS  0x81
  59 #define ACPI_THERMAL_NOTIFY_DEVICES     0x82
  60 #define ACPI_THERMAL_NOTIFY_CRITICAL    0xF0
  61 #define ACPI_THERMAL_NOTIFY_HOT         0xF1
  62 #define ACPI_THERMAL_MODE_ACTIVE        0x00
  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, 0444);
  79 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.\n");
  80
  81 static int off;
  82 module_param(off, int, 0);
  83 MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.\n");
  84
  85 static int psv;
  86 module_param(psv, int, 0644);
  87 MODULE_PARM_DESC(psv, "Disable or override all passive trip points.\n");
  88
  89 static int acpi_thermal_add(struct acpi_device *device);
  90 static int acpi_thermal_remove(struct acpi_device *device, int type);
  91 static int acpi_thermal_resume(struct acpi_device *device);
  92 static int acpi_thermal_state_open_fs(struct inode *inode, struct file *file);
  93 static int acpi_thermal_temp_open_fs(struct inode *inode, struct file *file);
  94 static int acpi_thermal_trip_open_fs(struct inode *inode, struct file *file);
  95 static int acpi_thermal_cooling_open_fs(struct inode *inode, struct file *file);
  96 static ssize_t acpi_thermal_write_cooling_mode(struct file *,
  97                                                const char __user *, size_t,
  98                                                loff_t *);
  99 static int acpi_thermal_polling_open_fs(struct inode *inode, struct file *file);
 100 static ssize_t acpi_thermal_write_polling(struct file *, const char __user *,
 101                                           size_t, loff_t *);
 102
 103 static const struct acpi_device_id  thermal_device_ids[] = {
 104         {ACPI_THERMAL_HID, 0},
 105         {"", 0},
 106 };
 107 MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
 108
 109 static struct acpi_driver acpi_thermal_driver = {
 110         .name = "thermal",
 111         .class = ACPI_THERMAL_CLASS,
 112         .ids = thermal_device_ids,
 113         .ops = {
 114                 .add = acpi_thermal_add,
 115                 .remove = acpi_thermal_remove,
 116                 .resume = acpi_thermal_resume,
 117                 },
 118 };
 119
 120 struct acpi_thermal_state {
 121         u8 critical:1;
 122         u8 hot:1;
 123         u8 passive:1;
 124         u8 active:1;
 125         u8 reserved:4;
 126         int active_index;
 127 };
 128
 129 struct acpi_thermal_state_flags {
 130         u8 valid:1;
 131         u8 enabled:1;
 132         u8 reserved:6;
 133 };
 134
 135 struct acpi_thermal_critical {
 136         struct acpi_thermal_state_flags flags;
 137         unsigned long temperature;
 138 };
 139
 140 struct acpi_thermal_hot {
 141         struct acpi_thermal_state_flags flags;
 142         unsigned long temperature;
 143 };
 144
 145 struct acpi_thermal_passive {
 146         struct acpi_thermal_state_flags flags;
 147         unsigned long temperature;
 148         unsigned long tc1;
 149         unsigned long tc2;
 150         unsigned long tsp;
 151         struct acpi_handle_list devices;
 152 };
 153
 154 struct acpi_thermal_active {
 155         struct acpi_thermal_state_flags flags;
 156         unsigned long temperature;
 157         struct acpi_handle_list devices;
 158 };
 159
 160 struct acpi_thermal_trips {
 161         struct acpi_thermal_critical critical;
 162         struct acpi_thermal_hot hot;
 163         struct acpi_thermal_passive passive;
 164         struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
 165 };
 166
 167 struct acpi_thermal_flags {
 168         u8 cooling_mode:1;      /* _SCP */
 169         u8 devices:1;           /* _TZD */
 170         u8 reserved:6;
 171 };
 172
 173 struct acpi_thermal {
 174         struct acpi_device * device;
 175         acpi_bus_id name;
 176         unsigned long temperature;
 177         unsigned long last_temperature;
 178         unsigned long polling_frequency;
 179         volatile u8 zombie;
 180         struct acpi_thermal_flags flags;
 181         struct acpi_thermal_state state;
 182         struct acpi_thermal_trips trips;
 183         struct acpi_handle_list devices;
 184         struct timer_list timer;
 185 };
 186
 187 static const struct file_operations acpi_thermal_state_fops = {
 188         .open = acpi_thermal_state_open_fs,
 189         .read = seq_read,
 190         .llseek = seq_lseek,
 191         .release = single_release,
 192 };
 193
 194 static const struct file_operations acpi_thermal_temp_fops = {
 195         .open = acpi_thermal_temp_open_fs,
 196         .read = seq_read,
 197         .llseek = seq_lseek,
 198         .release = single_release,
 199 };
 200
 201 static const struct file_operations acpi_thermal_trip_fops = {
 202         .open = acpi_thermal_trip_open_fs,
 203         .read = seq_read,
 204         .llseek = seq_lseek,
 205         .release = single_release,
 206 };
 207
 208 static const struct file_operations acpi_thermal_cooling_fops = {
 209         .open = acpi_thermal_cooling_open_fs,
 210         .read = seq_read,
 211         .write = acpi_thermal_write_cooling_mode,
 212         .llseek = seq_lseek,
 213         .release = single_release,
 214 };
 215
 216 static const struct file_operations acpi_thermal_polling_fops = {
 217         .open = acpi_thermal_polling_open_fs,
 218         .read = seq_read,
 219         .write = acpi_thermal_write_polling,
 220         .llseek = seq_lseek,
 221         .release = single_release,
 222 };
 223
 224 /* --------------------------------------------------------------------------
 225                              Thermal Zone Management
 226    -------------------------------------------------------------------------- */
 227
 228 static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
 229 {
 230         acpi_status status = AE_OK;
 231
 232
 233         if (!tz)
 234                 return -EINVAL;
 235
 236         tz->last_temperature = tz->temperature;
 237
 238         status =
 239             acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tz->temperature);
 240         if (ACPI_FAILURE(status))
 241                 return -ENODEV;
 242
 243         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Temperature is %lu dK\n",
 244                           tz->temperature));
 245
 246         return 0;
 247 }
 248
 249 static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
 250 {
 251         acpi_status status = AE_OK;
 252
 253
 254         if (!tz)
 255                 return -EINVAL;
 256
 257         status =
 258             acpi_evaluate_integer(tz->device->handle, "_TZP", NULL,
 259                                   &tz->polling_frequency);
 260         if (ACPI_FAILURE(status))
 261                 return -ENODEV;
 262
 263         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Polling frequency is %lu dS\n",
 264                           tz->polling_frequency));
 265
 266         return 0;
 267 }
 268
 269 static int acpi_thermal_set_polling(struct acpi_thermal *tz, int seconds)
 270 {
 271
 272         if (!tz)
 273                 return -EINVAL;
 274
 275         tz->polling_frequency = seconds * 10;   /* Convert value to deci-seconds */
 276
 277         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 278                           "Polling frequency set to %lu seconds\n",
 279                           tz->polling_frequency/10));
 280
 281         return 0;
 282 }
 283
 284 static int acpi_thermal_set_cooling_mode(struct acpi_thermal *tz, int mode)
 285 {
 286         acpi_status status = AE_OK;
 287         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 288         struct acpi_object_list arg_list = { 1, &arg0 };
 289         acpi_handle handle = NULL;
 290
 291
 292         if (!tz)
 293                 return -EINVAL;
 294
 295         status = acpi_get_handle(tz->device->handle, "_SCP", &handle);
 296         if (ACPI_FAILURE(status)) {
 297                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "_SCP not present\n"));
 298                 return -ENODEV;
 299         }
 300
 301         arg0.integer.value = mode;
 302
 303         status = acpi_evaluate_object(handle, NULL, &arg_list, NULL);
 304         if (ACPI_FAILURE(status))
 305                 return -ENODEV;
 306
 307         return 0;
 308 }
 309
 310 static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
 311 {
 312         acpi_status status = AE_OK;
 313         int i = 0;
 314
 315
 316         if (!tz)
 317                 return -EINVAL;
 318
 319         /* Critical Shutdown (required) */
 320
 321         status = acpi_evaluate_integer(tz->device->handle, "_CRT", NULL,
 322                                        &tz->trips.critical.temperature);
 323         if (ACPI_FAILURE(status)) {
 324                 tz->trips.critical.flags.valid = 0;
 325                 ACPI_EXCEPTION((AE_INFO, status, "No critical threshold"));
 326                 return -ENODEV;
 327         } else {
 328                 tz->trips.critical.flags.valid = 1;
 329                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 330                                   "Found critical threshold [%lu]\n",
 331                                   tz->trips.critical.temperature));
 332         }
 333
 334         /* Critical Sleep (optional) */
 335
 336         status =
 337             acpi_evaluate_integer(tz->device->handle, "_HOT", NULL,
 338                                   &tz->trips.hot.temperature);
 339         if (ACPI_FAILURE(status)) {
 340                 tz->trips.hot.flags.valid = 0;
 341                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No hot threshold\n"));
 342         } else {
 343                 tz->trips.hot.flags.valid = 1;
 344                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found hot threshold [%lu]\n",
 345                                   tz->trips.hot.temperature));
 346         }
 347
 348         /* Passive: Processors (optional) */
 349
 350         if (psv == -1) {
 351                 status = AE_SUPPORT;
 352         } else if (psv > 0) {
 353                 tz->trips.passive.temperature = CELSIUS_TO_KELVIN(psv);
 354                 status = AE_OK;
 355         } else {
 356                 status = acpi_evaluate_integer(tz->device->handle,
 357                         "_PSV", NULL, &tz->trips.passive.temperature);
 358         }
 359
 360         if (ACPI_FAILURE(status)) {
 361                 tz->trips.passive.flags.valid = 0;
 362                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No passive threshold\n"));
 363         } else {
 364                 tz->trips.passive.flags.valid = 1;
 365
 366                 status =
 367                     acpi_evaluate_integer(tz->device->handle, "_TC1", NULL,
 368                                           &tz->trips.passive.tc1);
 369                 if (ACPI_FAILURE(status))
 370                         tz->trips.passive.flags.valid = 0;
 371
 372                 status =
 373                     acpi_evaluate_integer(tz->device->handle, "_TC2", NULL,
 374                                           &tz->trips.passive.tc2);
 375                 if (ACPI_FAILURE(status))
 376                         tz->trips.passive.flags.valid = 0;
 377
 378                 status =
 379                     acpi_evaluate_integer(tz->device->handle, "_TSP", NULL,
 380                                           &tz->trips.passive.tsp);
 381                 if (ACPI_FAILURE(status))
 382                         tz->trips.passive.flags.valid = 0;
 383
 384                 status =
 385                     acpi_evaluate_reference(tz->device->handle, "_PSL", NULL,
 386                                             &tz->trips.passive.devices);
 387                 if (ACPI_FAILURE(status))
 388                         tz->trips.passive.flags.valid = 0;
 389
 390                 if (!tz->trips.passive.flags.valid)
 391                         printk(KERN_WARNING PREFIX "Invalid passive threshold\n");
 392                 else
 393                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 394                                           "Found passive threshold [%lu]\n",
 395                                           tz->trips.passive.temperature));
 396         }
 397
 398         /* Active: Fans, etc. (optional) */
 399
 400         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 401
 402                 char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
 403
 404                 status =
 405                     acpi_evaluate_integer(tz->device->handle, name, NULL,
 406                                           &tz->trips.active[i].temperature);
 407                 if (ACPI_FAILURE(status))
 408                         break;
 409
 410                 name[2] = 'L';
 411                 status =
 412                     acpi_evaluate_reference(tz->device->handle, name, NULL,
 413                                             &tz->trips.active[i].devices);
 414                 if (ACPI_SUCCESS(status)) {
 415                         tz->trips.active[i].flags.valid = 1;
 416                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 417                                           "Found active threshold [%d]:[%lu]\n",
 418                                           i, tz->trips.active[i].temperature));
 419                 } else
 420                         ACPI_EXCEPTION((AE_INFO, status,
 421                                         "Invalid active threshold [%d]", i));
 422         }
 423
 424         return 0;
 425 }
 426
 427 static int acpi_thermal_get_devices(struct acpi_thermal *tz)
 428 {
 429         acpi_status status = AE_OK;
 430
 431
 432         if (!tz)
 433                 return -EINVAL;
 434
 435         status =
 436             acpi_evaluate_reference(tz->device->handle, "_TZD", NULL, &tz->devices);
 437         if (ACPI_FAILURE(status))
 438                 return -ENODEV;
 439
 440         return 0;
 441 }
 442
 443 static int acpi_thermal_critical(struct acpi_thermal *tz)
 444 {
 445         if (!tz || !tz->trips.critical.flags.valid)
 446                 return -EINVAL;
 447
 448         if (tz->temperature >= tz->trips.critical.temperature) {
 449                 printk(KERN_WARNING PREFIX "Critical trip point\n");
 450                 tz->trips.critical.flags.enabled = 1;
 451         } else if (tz->trips.critical.flags.enabled)
 452                 tz->trips.critical.flags.enabled = 0;
 453
 454         printk(KERN_EMERG
 455                "Critical temperature reached (%ld C), shutting down.\n",
 456                KELVIN_TO_CELSIUS(tz->temperature));
 457         acpi_bus_generate_event(tz->device, ACPI_THERMAL_NOTIFY_CRITICAL,
 458                                 tz->trips.critical.flags.enabled);
 459
 460         orderly_poweroff(true);
 461
 462         return 0;
 463 }
 464
 465 static int acpi_thermal_hot(struct acpi_thermal *tz)
 466 {
 467         if (!tz || !tz->trips.hot.flags.valid)
 468                 return -EINVAL;
 469
 470         if (tz->temperature >= tz->trips.hot.temperature) {
 471                 printk(KERN_WARNING PREFIX "Hot trip point\n");
 472                 tz->trips.hot.flags.enabled = 1;
 473         } else if (tz->trips.hot.flags.enabled)
 474                 tz->trips.hot.flags.enabled = 0;
 475
 476         acpi_bus_generate_event(tz->device, ACPI_THERMAL_NOTIFY_HOT,
 477                                 tz->trips.hot.flags.enabled);
 478
 479         /* TBD: Call user-mode "sleep(S4)" function */
 480
 481         return 0;
 482 }
 483
 484 static void acpi_thermal_passive(struct acpi_thermal *tz)
 485 {
 486         int result = 1;
 487         struct acpi_thermal_passive *passive = NULL;
 488         int trend = 0;
 489         int i = 0;
 490
 491
 492         if (!tz || !tz->trips.passive.flags.valid)
 493                 return;
 494
 495         passive = &(tz->trips.passive);
 496
 497         /*
 498          * Above Trip?
 499          * -----------
 500          * Calculate the thermal trend (using the passive cooling equation)
 501          * and modify the performance limit for all passive cooling devices
 502          * accordingly.  Note that we assume symmetry.
 503          */
 504         if (tz->temperature >= passive->temperature) {
 505                 trend =
 506                     (passive->tc1 * (tz->temperature - tz->last_temperature)) +
 507                     (passive->tc2 * (tz->temperature - passive->temperature));
 508                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 509                                   "trend[%d]=(tc1[%lu]*(tmp[%lu]-last[%lu]))+(tc2[%lu]*(tmp[%lu]-psv[%lu]))\n",
 510                                   trend, passive->tc1, tz->temperature,
 511                                   tz->last_temperature, passive->tc2,
 512                                   tz->temperature, passive->temperature));
 513                 passive->flags.enabled = 1;
 514                 /* Heating up? */
 515                 if (trend > 0)
 516                         for (i = 0; i < passive->devices.count; i++)
 517                                 acpi_processor_set_thermal_limit(passive->
 518                                                                  devices.
 519                                                                  handles[i],
 520                                                                  ACPI_PROCESSOR_LIMIT_INCREMENT);
 521                 /* Cooling off? */
 522                 else if (trend < 0) {
 523                         for (i = 0; i < passive->devices.count; i++)
 524                                 /*
 525                                  * assume that we are on highest
 526                                  * freq/lowest thrott and can leave
 527                                  * passive mode, even in error case
 528                                  */
 529                                 if (!acpi_processor_set_thermal_limit
 530                                     (passive->devices.handles[i],
 531                                      ACPI_PROCESSOR_LIMIT_DECREMENT))
 532                                         result = 0;
 533                         /*
 534                          * Leave cooling mode, even if the temp might
 535                          * higher than trip point This is because some
 536                          * machines might have long thermal polling
 537                          * frequencies (tsp) defined. We will fall back
 538                          * into passive mode in next cycle (probably quicker)
 539                          */
 540                         if (result) {
 541                                 passive->flags.enabled = 0;
 542                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 543                                                   "Disabling passive cooling, still above threshold,"
 544                                                   " but we are cooling down\n"));
 545                         }
 546                 }
 547                 return;
 548         }
 549
 550         /*
 551          * Below Trip?
 552          * -----------
 553          * Implement passive cooling hysteresis to slowly increase performance
 554          * and avoid thrashing around the passive trip point.  Note that we
 555          * assume symmetry.
 556          */
 557         if (!passive->flags.enabled)
 558                 return;
 559         for (i = 0; i < passive->devices.count; i++)
 560                 if (!acpi_processor_set_thermal_limit
 561                     (passive->devices.handles[i],
 562                      ACPI_PROCESSOR_LIMIT_DECREMENT))
 563                         result = 0;
 564         if (result) {
 565                 passive->flags.enabled = 0;
 566                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 567                                   "Disabling passive cooling (zone is cool)\n"));
 568         }
 569 }
 570
 571 static void acpi_thermal_active(struct acpi_thermal *tz)
 572 {
 573         int result = 0;
 574         struct acpi_thermal_active *active = NULL;
 575         int i = 0;
 576         int j = 0;
 577         unsigned long maxtemp = 0;
 578
 579
 580         if (!tz)
 581                 return;
 582
 583         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 584                 active = &(tz->trips.active[i]);
 585                 if (!active || !active->flags.valid)
 586                         break;
 587                 if (tz->temperature >= active->temperature) {
 588                         /*
 589                          * Above Threshold?
 590                          * ----------------
 591                          * If not already enabled, turn ON all cooling devices
 592                          * associated with this active threshold.
 593                          */
 594                         if (active->temperature > maxtemp)
 595                                 tz->state.active_index = i;
 596                         maxtemp = active->temperature;
 597                         if (active->flags.enabled)
 598                                 continue;
 599                         for (j = 0; j < active->devices.count; j++) {
 600                                 result =
 601                                     acpi_bus_set_power(active->devices.
 602                                                        handles[j],
 603                                                        ACPI_STATE_D0);
 604                                 if (result) {
 605                                         printk(KERN_WARNING PREFIX
 606                                                       "Unable to turn cooling device [%p] 'on'\n",
 607                                                       active->devices.
 608                                                       handles[j]);
 609                                         continue;
 610                                 }
 611                                 active->flags.enabled = 1;
 612                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 613                                                   "Cooling device [%p] now 'on'\n",
 614                                                   active->devices.handles[j]));
 615                         }
 616                         continue;
 617                 }
 618                 if (!active->flags.enabled)
 619                         continue;
 620                 /*
 621                  * Below Threshold?
 622                  * ----------------
 623                  * Turn OFF all cooling devices associated with this
 624                  * threshold.
 625                  */
 626                 for (j = 0; j < active->devices.count; j++) {
 627                         result = acpi_bus_set_power(active->devices.handles[j],
 628                                                     ACPI_STATE_D3);
 629                         if (result) {
 630                                 printk(KERN_WARNING PREFIX
 631                                               "Unable to turn cooling device [%p] 'off'\n",
 632                                               active->devices.handles[j]);
 633                                 continue;
 634                         }
 635                         active->flags.enabled = 0;
 636                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 637                                           "Cooling device [%p] now 'off'\n",
 638                                           active->devices.handles[j]));
 639                 }
 640         }
 641 }
 642
 643 static void acpi_thermal_check(void *context);
 644
 645 static void acpi_thermal_run(unsigned long data)
 646 {
 647         struct acpi_thermal *tz = (struct acpi_thermal *)data;
 648         if (!tz->zombie)
 649                 acpi_os_execute(OSL_GPE_HANDLER, acpi_thermal_check, (void *)data);
 650 }
 651
 652 static void acpi_thermal_check(void *data)
 653 {
 654         int result = 0;
 655         struct acpi_thermal *tz = data;
 656         unsigned long sleep_time = 0;
 657         int i = 0;
 658         struct acpi_thermal_state state;
 659
 660
 661         if (!tz) {
 662                 printk(KERN_ERR PREFIX "Invalid (NULL) context\n");
 663                 return;
 664         }
 665
 666         state = tz->state;
 667
 668         result = acpi_thermal_get_temperature(tz);
 669         if (result)
 670                 return;
 671
 672         memset(&tz->state, 0, sizeof(tz->state));
 673
 674         /*
 675          * Check Trip Points
 676          * -----------------
 677          * Compare the current temperature to the trip point values to see
 678          * if we've entered one of the thermal policy states.  Note that
 679          * this function determines when a state is entered, but the
 680          * individual policy decides when it is exited (e.g. hysteresis).
 681          */
 682         if (tz->trips.critical.flags.valid)
 683                 state.critical |=
 684                     (tz->temperature >= tz->trips.critical.temperature);
 685         if (tz->trips.hot.flags.valid)
 686                 state.hot |= (tz->temperature >= tz->trips.hot.temperature);
 687         if (tz->trips.passive.flags.valid)
 688                 state.passive |=
 689                     (tz->temperature >= tz->trips.passive.temperature);
 690         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
 691                 if (tz->trips.active[i].flags.valid)
 692                         state.active |=
 693                             (tz->temperature >=
 694                              tz->trips.active[i].temperature);
 695
 696         /*
 697          * Invoke Policy
 698          * -------------
 699          * Separated from the above check to allow individual policy to
 700          * determine when to exit a given state.
 701          */
 702         if (state.critical)
 703                 acpi_thermal_critical(tz);
 704         if (state.hot)
 705                 acpi_thermal_hot(tz);
 706         if (state.passive)
 707                 acpi_thermal_passive(tz);
 708         if (state.active)
 709                 acpi_thermal_active(tz);
 710
 711         /*
 712          * Calculate State
 713          * ---------------
 714          * Again, separated from the above two to allow independent policy
 715          * decisions.
 716          */
 717         tz->state.critical = tz->trips.critical.flags.enabled;
 718         tz->state.hot = tz->trips.hot.flags.enabled;
 719         tz->state.passive = tz->trips.passive.flags.enabled;
 720         tz->state.active = 0;
 721         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
 722                 tz->state.active |= tz->trips.active[i].flags.enabled;
 723
 724         /*
 725          * Calculate Sleep Time
 726          * --------------------
 727          * If we're in the passive state, use _TSP's value.  Otherwise
 728          * use the default polling frequency (e.g. _TZP).  If no polling
 729          * frequency is specified then we'll wait forever (at least until
 730          * a thermal event occurs).  Note that _TSP and _TZD values are
 731          * given in 1/10th seconds (we must covert to milliseconds).
 732          */
 733         if (tz->state.passive)
 734                 sleep_time = tz->trips.passive.tsp * 100;
 735         else if (tz->polling_frequency > 0)
 736                 sleep_time = tz->polling_frequency * 100;
 737
 738         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s: temperature[%lu] sleep[%lu]\n",
 739                           tz->name, tz->temperature, sleep_time));
 740
 741         /*
 742          * Schedule Next Poll
 743          * ------------------
 744          */
 745         if (!sleep_time) {
 746                 if (timer_pending(&(tz->timer)))
 747                         del_timer(&(tz->timer));
 748         } else {
 749                 if (timer_pending(&(tz->timer)))
 750                         mod_timer(&(tz->timer),
 751                                         jiffies + (HZ * sleep_time) / 1000);
 752                 else {
 753                         tz->timer.data = (unsigned long)tz;
 754                         tz->timer.function = acpi_thermal_run;
 755                         tz->timer.expires = jiffies + (HZ * sleep_time) / 1000;
 756                         add_timer(&(tz->timer));
 757                 }
 758         }
 759
 760         return;
 761 }
 762
 763 /* --------------------------------------------------------------------------
 764                               FS Interface (/proc)
 765    -------------------------------------------------------------------------- */
 766
 767 static struct proc_dir_entry *acpi_thermal_dir;
 768
 769 static int acpi_thermal_state_seq_show(struct seq_file *seq, void *offset)
 770 {
 771         struct acpi_thermal *tz = seq->private;
 772
 773
 774         if (!tz)
 775                 goto end;
 776
 777         seq_puts(seq, "state:                   ");
 778
 779         if (!tz->state.critical && !tz->state.hot && !tz->state.passive
 780             && !tz->state.active)
 781                 seq_puts(seq, "ok\n");
 782         else {
 783                 if (tz->state.critical)
 784                         seq_puts(seq, "critical ");
 785                 if (tz->state.hot)
 786                         seq_puts(seq, "hot ");
 787                 if (tz->state.passive)
 788                         seq_puts(seq, "passive ");
 789                 if (tz->state.active)
 790                         seq_printf(seq, "active[%d]", tz->state.active_index);
 791                 seq_puts(seq, "\n");
 792         }
 793
 794       end:
 795         return 0;
 796 }
 797
 798 static int acpi_thermal_state_open_fs(struct inode *inode, struct file *file)
 799 {
 800         return single_open(file, acpi_thermal_state_seq_show, PDE(inode)->data);
 801 }
 802
 803 static int acpi_thermal_temp_seq_show(struct seq_file *seq, void *offset)
 804 {
 805         int result = 0;
 806         struct acpi_thermal *tz = seq->private;
 807
 808
 809         if (!tz)
 810                 goto end;
 811
 812         result = acpi_thermal_get_temperature(tz);
 813         if (result)
 814                 goto end;
 815
 816         seq_printf(seq, "temperature:             %ld C\n",
 817                    KELVIN_TO_CELSIUS(tz->temperature));
 818
 819       end:
 820         return 0;
 821 }
 822
 823 static int acpi_thermal_temp_open_fs(struct inode *inode, struct file *file)
 824 {
 825         return single_open(file, acpi_thermal_temp_seq_show, PDE(inode)->data);
 826 }
 827
 828 static int acpi_thermal_trip_seq_show(struct seq_file *seq, void *offset)
 829 {
 830         struct acpi_thermal *tz = seq->private;
 831         struct acpi_device *device;
 832         acpi_status status;
 833
 834         int i = 0;
 835         int j = 0;
 836
 837
 838         if (!tz)
 839                 goto end;
 840
 841         if (tz->trips.critical.flags.valid)
 842                 seq_printf(seq, "critical (S5):           %ld C\n",
 843                            KELVIN_TO_CELSIUS(tz->trips.critical.temperature));
 844
 845         if (tz->trips.hot.flags.valid)
 846                 seq_printf(seq, "hot (S4):                %ld C\n",
 847                            KELVIN_TO_CELSIUS(tz->trips.hot.temperature));
 848
 849         if (tz->trips.passive.flags.valid) {
 850                 seq_printf(seq,
 851                            "passive:                 %ld C: tc1=%lu tc2=%lu tsp=%lu devices=",
 852                            KELVIN_TO_CELSIUS(tz->trips.passive.temperature),
 853                            tz->trips.passive.tc1, tz->trips.passive.tc2,
 854                            tz->trips.passive.tsp);
 855                 for (j = 0; j < tz->trips.passive.devices.count; j++) {
 856                         status = acpi_bus_get_device(tz->trips.passive.devices.
 857                                                      handles[j], &device);
 858                         seq_printf(seq, "%4.4s ", status ? "" :
 859                                    acpi_device_bid(device));
 860                 }
 861                 seq_puts(seq, "\n");
 862         }
 863
 864         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 865                 if (!(tz->trips.active[i].flags.valid))
 866                         break;
 867                 seq_printf(seq, "active[%d]:               %ld C: devices=",
 868                            i,
 869                            KELVIN_TO_CELSIUS(tz->trips.active[i].temperature));
 870                 for (j = 0; j < tz->trips.active[i].devices.count; j++){
 871                         status = acpi_bus_get_device(tz->trips.active[i].
 872                                                      devices.handles[j],
 873                                                      &device);
 874                         seq_printf(seq, "%4.4s ", status ? "" :
 875                                    acpi_device_bid(device));
 876                 }
 877                 seq_puts(seq, "\n");
 878         }
 879
 880       end:
 881         return 0;
 882 }
 883
 884 static int acpi_thermal_trip_open_fs(struct inode *inode, struct file *file)
 885 {
 886         return single_open(file, acpi_thermal_trip_seq_show, PDE(inode)->data);
 887 }
 888
 889 static int acpi_thermal_cooling_seq_show(struct seq_file *seq, void *offset)
 890 {
 891         struct acpi_thermal *tz = seq->private;
 892
 893
 894         if (!tz)
 895                 goto end;
 896
 897         if (!tz->flags.cooling_mode)
 898                 seq_puts(seq, "<setting not supported>\n");
 899         else
 900                 seq_puts(seq, "0 - Active; 1 - Passive\n");
 901
 902       end:
 903         return 0;
 904 }
 905
 906 static int acpi_thermal_cooling_open_fs(struct inode *inode, struct file *file)
 907 {
 908         return single_open(file, acpi_thermal_cooling_seq_show,
 909                            PDE(inode)->data);
 910 }
 911
 912 static ssize_t
 913 acpi_thermal_write_cooling_mode(struct file *file,
 914                                 const char __user * buffer,
 915                                 size_t count, loff_t * ppos)
 916 {
 917         struct seq_file *m = file->private_data;
 918         struct acpi_thermal *tz = m->private;
 919         int result = 0;
 920         char mode_string[12] = { '\0' };
 921
 922
 923         if (!tz || (count > sizeof(mode_string) - 1))
 924                 return -EINVAL;
 925
 926         if (!tz->flags.cooling_mode)
 927                 return -ENODEV;
 928
 929         if (copy_from_user(mode_string, buffer, count))
 930                 return -EFAULT;
 931
 932         mode_string[count] = '\0';
 933
 934         result = acpi_thermal_set_cooling_mode(tz,
 935                                                simple_strtoul(mode_string, NULL,
 936                                                               0));
 937         if (result)
 938                 return result;
 939
 940         acpi_thermal_check(tz);
 941
 942         return count;
 943 }
 944
 945 static int acpi_thermal_polling_seq_show(struct seq_file *seq, void *offset)
 946 {
 947         struct acpi_thermal *tz = seq->private;
 948
 949
 950         if (!tz)
 951                 goto end;
 952
 953         if (!tz->polling_frequency) {
 954                 seq_puts(seq, "<polling disabled>\n");
 955                 goto end;
 956         }
 957
 958         seq_printf(seq, "polling frequency:       %lu seconds\n",
 959                    (tz->polling_frequency / 10));
 960
 961       end:
 962         return 0;
 963 }
 964
 965 static int acpi_thermal_polling_open_fs(struct inode *inode, struct file *file)
 966 {
 967         return single_open(file, acpi_thermal_polling_seq_show,
 968                            PDE(inode)->data);
 969 }
 970
 971 static ssize_t
 972 acpi_thermal_write_polling(struct file *file,
 973                            const char __user * buffer,
 974                            size_t count, loff_t * ppos)
 975 {
 976         struct seq_file *m = file->private_data;
 977         struct acpi_thermal *tz = m->private;
 978         int result = 0;
 979         char polling_string[12] = { '\0' };
 980         int seconds = 0;
 981
 982
 983         if (!tz || (count > sizeof(polling_string) - 1))
 984                 return -EINVAL;
 985
 986         if (copy_from_user(polling_string, buffer, count))
 987                 return -EFAULT;
 988
 989         polling_string[count] = '\0';
 990
 991         seconds = simple_strtoul(polling_string, NULL, 0);
 992
 993         result = acpi_thermal_set_polling(tz, seconds);
 994         if (result)
 995                 return result;
 996
 997         acpi_thermal_check(tz);
 998
 999         return count;
1000 }
1001
1002 static int acpi_thermal_add_fs(struct acpi_device *device)
1003 {
1004         struct proc_dir_entry *entry = NULL;
1005
1006
1007         if (!acpi_device_dir(device)) {
1008                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
1009                                                      acpi_thermal_dir);
1010                 if (!acpi_device_dir(device))
1011                         return -ENODEV;
1012                 acpi_device_dir(device)->owner = THIS_MODULE;
1013         }
1014
1015         /* 'state' [R] */
1016         entry = create_proc_entry(ACPI_THERMAL_FILE_STATE,
1017                                   S_IRUGO, acpi_device_dir(device));
1018         if (!entry)
1019                 return -ENODEV;
1020         else {
1021                 entry->proc_fops = &acpi_thermal_state_fops;
1022                 entry->data = acpi_driver_data(device);
1023                 entry->owner = THIS_MODULE;
1024         }
1025
1026         /* 'temperature' [R] */
1027         entry = create_proc_entry(ACPI_THERMAL_FILE_TEMPERATURE,
1028                                   S_IRUGO, acpi_device_dir(device));
1029         if (!entry)
1030                 return -ENODEV;
1031         else {
1032                 entry->proc_fops = &acpi_thermal_temp_fops;
1033                 entry->data = acpi_driver_data(device);
1034                 entry->owner = THIS_MODULE;
1035         }
1036
1037         /* 'trip_points' [R/W] */
1038         entry = create_proc_entry(ACPI_THERMAL_FILE_TRIP_POINTS,
1039                                   S_IFREG | S_IRUGO | S_IWUSR,
1040                                   acpi_device_dir(device));
1041         if (!entry)
1042                 return -ENODEV;
1043         else {
1044                 entry->proc_fops = &acpi_thermal_trip_fops;
1045                 entry->data = acpi_driver_data(device);
1046                 entry->owner = THIS_MODULE;
1047         }
1048
1049         /* 'cooling_mode' [R/W] */
1050         entry = create_proc_entry(ACPI_THERMAL_FILE_COOLING_MODE,
1051                                   S_IFREG | S_IRUGO | S_IWUSR,
1052                                   acpi_device_dir(device));
1053         if (!entry)
1054                 return -ENODEV;
1055         else {
1056                 entry->proc_fops = &acpi_thermal_cooling_fops;
1057                 entry->data = acpi_driver_data(device);
1058                 entry->owner = THIS_MODULE;
1059         }
1060
1061         /* 'polling_frequency' [R/W] */
1062         entry = create_proc_entry(ACPI_THERMAL_FILE_POLLING_FREQ,
1063                                   S_IFREG | S_IRUGO | S_IWUSR,
1064                                   acpi_device_dir(device));
1065         if (!entry)
1066                 return -ENODEV;
1067         else {
1068                 entry->proc_fops = &acpi_thermal_polling_fops;
1069                 entry->data = acpi_driver_data(device);
1070                 entry->owner = THIS_MODULE;
1071         }
1072
1073         return 0;
1074 }
1075
1076 static int acpi_thermal_remove_fs(struct acpi_device *device)
1077 {
1078
1079         if (acpi_device_dir(device)) {
1080                 remove_proc_entry(ACPI_THERMAL_FILE_POLLING_FREQ,
1081                                   acpi_device_dir(device));
1082                 remove_proc_entry(ACPI_THERMAL_FILE_COOLING_MODE,
1083                                   acpi_device_dir(device));
1084                 remove_proc_entry(ACPI_THERMAL_FILE_TRIP_POINTS,
1085                                   acpi_device_dir(device));
1086                 remove_proc_entry(ACPI_THERMAL_FILE_TEMPERATURE,
1087                                   acpi_device_dir(device));
1088                 remove_proc_entry(ACPI_THERMAL_FILE_STATE,
1089                                   acpi_device_dir(device));
1090                 remove_proc_entry(acpi_device_bid(device), acpi_thermal_dir);
1091                 acpi_device_dir(device) = NULL;
1092         }
1093
1094         return 0;
1095 }
1096
1097 /* --------------------------------------------------------------------------
1098                                  Driver Interface
1099    -------------------------------------------------------------------------- */
1100
1101 static void acpi_thermal_notify(acpi_handle handle, u32 event, void *data)
1102 {
1103         struct acpi_thermal *tz = data;
1104         struct acpi_device *device = NULL;
1105
1106
1107         if (!tz)
1108                 return;
1109
1110         device = tz->device;
1111
1112         switch (event) {
1113         case ACPI_THERMAL_NOTIFY_TEMPERATURE:
1114                 acpi_thermal_check(tz);
1115                 break;
1116         case ACPI_THERMAL_NOTIFY_THRESHOLDS:
1117                 acpi_thermal_get_trip_points(tz);
1118                 acpi_thermal_check(tz);
1119                 acpi_bus_generate_event(device, event, 0);
1120                 break;
1121         case ACPI_THERMAL_NOTIFY_DEVICES:
1122                 if (tz->flags.devices)
1123                         acpi_thermal_get_devices(tz);
1124                 acpi_bus_generate_event(device, event, 0);
1125                 break;
1126         default:
1127                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1128                                   "Unsupported event [0x%x]\n", event));
1129                 break;
1130         }
1131
1132         return;
1133 }
1134
1135 static int acpi_thermal_get_info(struct acpi_thermal *tz)
1136 {
1137         int result = 0;
1138
1139
1140         if (!tz)
1141                 return -EINVAL;
1142
1143         /* Get temperature [_TMP] (required) */
1144         result = acpi_thermal_get_temperature(tz);
1145         if (result)
1146                 return result;
1147
1148         /* Get trip points [_CRT, _PSV, etc.] (required) */
1149         result = acpi_thermal_get_trip_points(tz);
1150         if (result)
1151                 return result;
1152
1153         /* Set the cooling mode [_SCP] to active cooling (default) */
1154         result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
1155         if (!result)
1156                 tz->flags.cooling_mode = 1;
1157
1158         /* Get default polling frequency [_TZP] (optional) */
1159         if (tzp)
1160                 tz->polling_frequency = tzp;
1161         else
1162                 acpi_thermal_get_polling_frequency(tz);
1163
1164         /* Get devices in this thermal zone [_TZD] (optional) */
1165         result = acpi_thermal_get_devices(tz);
1166         if (!result)
1167                 tz->flags.devices = 1;
1168
1169         return 0;
1170 }
1171
1172 static int acpi_thermal_add(struct acpi_device *device)
1173 {
1174         int result = 0;
1175         acpi_status status = AE_OK;
1176         struct acpi_thermal *tz = NULL;
1177
1178
1179         if (!device)
1180                 return -EINVAL;
1181
1182         tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
1183         if (!tz)
1184                 return -ENOMEM;
1185
1186         tz->device = device;
1187         strcpy(tz->name, device->pnp.bus_id);
1188         strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
1189         strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
1190         acpi_driver_data(device) = tz;
1191
1192         result = acpi_thermal_get_info(tz);
1193         if (result)
1194                 goto end;
1195
1196         result = acpi_thermal_add_fs(device);
1197         if (result)
1198                 goto end;
1199
1200         init_timer(&tz->timer);
1201
1202         acpi_thermal_check(tz);
1203
1204         status = acpi_install_notify_handler(device->handle,
1205                                              ACPI_DEVICE_NOTIFY,
1206                                              acpi_thermal_notify, tz);
1207         if (ACPI_FAILURE(status)) {
1208                 result = -ENODEV;
1209                 goto end;
1210         }
1211
1212         printk(KERN_INFO PREFIX "%s [%s] (%ld C)\n",
1213                acpi_device_name(device), acpi_device_bid(device),
1214                KELVIN_TO_CELSIUS(tz->temperature));
1215
1216       end:
1217         if (result) {
1218                 acpi_thermal_remove_fs(device);
1219                 kfree(tz);
1220         }
1221
1222         return result;
1223 }
1224
1225 static int acpi_thermal_remove(struct acpi_device *device, int type)
1226 {
1227         acpi_status status = AE_OK;
1228         struct acpi_thermal *tz = NULL;
1229
1230
1231         if (!device || !acpi_driver_data(device))
1232                 return -EINVAL;
1233
1234         tz = acpi_driver_data(device);
1235
1236         /* avoid timer adding new defer task */
1237         tz->zombie = 1;
1238         /* wait for running timer (on other CPUs) finish */
1239         del_timer_sync(&(tz->timer));
1240         /* synchronize deferred task */
1241         acpi_os_wait_events_complete(NULL);
1242         /* deferred task may reinsert timer */
1243         del_timer_sync(&(tz->timer));
1244
1245         status = acpi_remove_notify_handler(device->handle,
1246                                             ACPI_DEVICE_NOTIFY,
1247                                             acpi_thermal_notify);
1248
1249         /* Terminate policy */
1250         if (tz->trips.passive.flags.valid && tz->trips.passive.flags.enabled) {
1251                 tz->trips.passive.flags.enabled = 0;
1252                 acpi_thermal_passive(tz);
1253         }
1254         if (tz->trips.active[0].flags.valid
1255             && tz->trips.active[0].flags.enabled) {
1256                 tz->trips.active[0].flags.enabled = 0;
1257                 acpi_thermal_active(tz);
1258         }
1259
1260         acpi_thermal_remove_fs(device);
1261
1262         kfree(tz);
1263         return 0;
1264 }
1265
1266 static int acpi_thermal_resume(struct acpi_device *device)
1267 {
1268         struct acpi_thermal *tz = NULL;
1269         int i, j, power_state, result;
1270
1271
1272         if (!device || !acpi_driver_data(device))
1273                 return -EINVAL;
1274
1275         tz = acpi_driver_data(device);
1276
1277         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1278                 if (!(&tz->trips.active[i]))
1279                         break;
1280                 if (!tz->trips.active[i].flags.valid)
1281                         break;
1282                 tz->trips.active[i].flags.enabled = 1;
1283                 for (j = 0; j < tz->trips.active[i].devices.count; j++) {
1284                         result = acpi_bus_get_power(tz->trips.active[i].devices.
1285                             handles[j], &power_state);
1286                         if (result || (power_state != ACPI_STATE_D0)) {
1287                                 tz->trips.active[i].flags.enabled = 0;
1288                                 break;
1289                         }
1290                 }
1291                 tz->state.active |= tz->trips.active[i].flags.enabled;
1292         }
1293
1294         acpi_thermal_check(tz);
1295
1296         return AE_OK;
1297 }
1298
1299 static int __init acpi_thermal_init(void)
1300 {
1301         int result = 0;
1302
1303         if (off) {
1304                 printk(KERN_NOTICE "ACPI: thermal control disabled\n");
1305                 return -ENODEV;
1306         }
1307         acpi_thermal_dir = proc_mkdir(ACPI_THERMAL_CLASS, acpi_root_dir);
1308         if (!acpi_thermal_dir)
1309                 return -ENODEV;
1310         acpi_thermal_dir->owner = THIS_MODULE;
1311
1312         result = acpi_bus_register_driver(&acpi_thermal_driver);
1313         if (result < 0) {
1314                 remove_proc_entry(ACPI_THERMAL_CLASS, acpi_root_dir);
1315                 return -ENODEV;
1316         }
1317
1318         return 0;
1319 }
1320
1321 static void __exit acpi_thermal_exit(void)
1322 {
1323
1324         acpi_bus_unregister_driver(&acpi_thermal_driver);
1325
1326         remove_proc_entry(ACPI_THERMAL_CLASS, acpi_root_dir);
1327
1328         return;
1329 }
1330
1331 module_init(acpi_thermal_init);
1332 module_exit(acpi_thermal_exit);