drivers/acpi/thermal.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  acpi_thermal.c - ACPI Thermal Zone Driver ($Revision: 41 $)
   4  *
   5  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   7  *
   8  *  This driver fully implements the ACPI thermal policy as described in the
   9  *  ACPI 2.0 Specification.
  10  *
  11  *  TBD: 1. Implement passive cooling hysteresis.
  12  *       2. Enhance passive cooling (CPU) states/limit interface to support
  13  *          concepts of 'multiple limiters', upper/lower limits, etc.
  14  */
  15
  16 #define pr_fmt(fmt) "ACPI: thermal: " fmt
  17
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/dmi.h>
  21 #include <linux/init.h>
  22 #include <linux/slab.h>
  23 #include <linux/types.h>
  24 #include <linux/jiffies.h>
  25 #include <linux/kmod.h>
  26 #include <linux/reboot.h>
  27 #include <linux/device.h>
  28 #include <linux/thermal.h>
  29 #include <linux/acpi.h>
  30 #include <linux/workqueue.h>
  31 #include <linux/uaccess.h>
  32 #include <linux/units.h>
  33
  34 #define ACPI_THERMAL_CLASS              "thermal_zone"
  35 #define ACPI_THERMAL_DEVICE_NAME        "Thermal Zone"
  36 #define ACPI_THERMAL_NOTIFY_TEMPERATURE 0x80
  37 #define ACPI_THERMAL_NOTIFY_THRESHOLDS  0x81
  38 #define ACPI_THERMAL_NOTIFY_DEVICES     0x82
  39 #define ACPI_THERMAL_NOTIFY_CRITICAL    0xF0
  40 #define ACPI_THERMAL_NOTIFY_HOT         0xF1
  41 #define ACPI_THERMAL_MODE_ACTIVE        0x00
  42
  43 #define ACPI_THERMAL_MAX_ACTIVE 10
  44 #define ACPI_THERMAL_MAX_LIMIT_STR_LEN 65
  45
  46 MODULE_AUTHOR("Paul Diefenbaugh");
  47 MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
  48 MODULE_LICENSE("GPL");
  49
  50 static int act;
  51 module_param(act, int, 0644);
  52 MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");
  53
  54 static int crt;
  55 module_param(crt, int, 0644);
  56 MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");
  57
  58 static int tzp;
  59 module_param(tzp, int, 0444);
  60 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
  61
  62 static int nocrt;
  63 module_param(nocrt, int, 0);
  64 MODULE_PARM_DESC(nocrt, "Set to take no action upon ACPI thermal zone critical trips points.");
  65
  66 static int off;
  67 module_param(off, int, 0);
  68 MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
  69
  70 static int psv;
  71 module_param(psv, int, 0644);
  72 MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");
  73
  74 static struct workqueue_struct *acpi_thermal_pm_queue;
  75
  76 static int acpi_thermal_add(struct acpi_device *device);
  77 static int acpi_thermal_remove(struct acpi_device *device);
  78 static void acpi_thermal_notify(struct acpi_device *device, u32 event);
  79
  80 static const struct acpi_device_id  thermal_device_ids[] = {
  81         {ACPI_THERMAL_HID, 0},
  82         {"", 0},
  83 };
  84 MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
  85
  86 #ifdef CONFIG_PM_SLEEP
  87 static int acpi_thermal_suspend(struct device *dev);
  88 static int acpi_thermal_resume(struct device *dev);
  89 #else
  90 #define acpi_thermal_suspend NULL
  91 #define acpi_thermal_resume NULL
  92 #endif
  93 static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, acpi_thermal_suspend, acpi_thermal_resume);
  94
  95 static struct acpi_driver acpi_thermal_driver = {
  96         .name = "thermal",
  97         .class = ACPI_THERMAL_CLASS,
  98         .ids = thermal_device_ids,
  99         .ops = {
 100                 .add = acpi_thermal_add,
 101                 .remove = acpi_thermal_remove,
 102                 .notify = acpi_thermal_notify,
 103                 },
 104         .drv.pm = &acpi_thermal_pm,
 105 };
 106
 107 struct acpi_thermal_state {
 108         u8 critical:1;
 109         u8 hot:1;
 110         u8 passive:1;
 111         u8 active:1;
 112         u8 reserved:4;
 113         int active_index;
 114 };
 115
 116 struct acpi_thermal_state_flags {
 117         u8 valid:1;
 118         u8 enabled:1;
 119         u8 reserved:6;
 120 };
 121
 122 struct acpi_thermal_critical {
 123         struct acpi_thermal_state_flags flags;
 124         unsigned long temperature;
 125 };
 126
 127 struct acpi_thermal_hot {
 128         struct acpi_thermal_state_flags flags;
 129         unsigned long temperature;
 130 };
 131
 132 struct acpi_thermal_passive {
 133         struct acpi_thermal_state_flags flags;
 134         unsigned long temperature;
 135         unsigned long tc1;
 136         unsigned long tc2;
 137         unsigned long tsp;
 138         struct acpi_handle_list devices;
 139 };
 140
 141 struct acpi_thermal_active {
 142         struct acpi_thermal_state_flags flags;
 143         unsigned long temperature;
 144         struct acpi_handle_list devices;
 145 };
 146
 147 struct acpi_thermal_trips {
 148         struct acpi_thermal_critical critical;
 149         struct acpi_thermal_hot hot;
 150         struct acpi_thermal_passive passive;
 151         struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
 152 };
 153
 154 struct acpi_thermal_flags {
 155         u8 cooling_mode:1;      /* _SCP */
 156         u8 devices:1;           /* _TZD */
 157         u8 reserved:6;
 158 };
 159
 160 struct acpi_thermal {
 161         struct acpi_device * device;
 162         acpi_bus_id name;
 163         unsigned long temperature;
 164         unsigned long last_temperature;
 165         unsigned long polling_frequency;
 166         volatile u8 zombie;
 167         struct acpi_thermal_flags flags;
 168         struct acpi_thermal_state state;
 169         struct acpi_thermal_trips trips;
 170         struct acpi_handle_list devices;
 171         struct thermal_zone_device *thermal_zone;
 172         int kelvin_offset;      /* in millidegrees */
 173         struct work_struct thermal_check_work;
 174         struct mutex thermal_check_lock;
 175         refcount_t thermal_check_count;
 176 };
 177
 178 /* --------------------------------------------------------------------------
 179                              Thermal Zone Management
 180    -------------------------------------------------------------------------- */
 181
 182 static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
 183 {
 184         acpi_status status = AE_OK;
 185         unsigned long long tmp;
 186
 187         if (!tz)
 188                 return -EINVAL;
 189
 190         tz->last_temperature = tz->temperature;
 191
 192         status = acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tmp);
 193         if (ACPI_FAILURE(status))
 194                 return -ENODEV;
 195
 196         tz->temperature = tmp;
 197
 198         acpi_handle_debug(tz->device->handle, "Temperature is %lu dK\n",
 199                           tz->temperature);
 200
 201         return 0;
 202 }
 203
 204 static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
 205 {
 206         acpi_status status = AE_OK;
 207         unsigned long long tmp;
 208
 209         if (!tz)
 210                 return -EINVAL;
 211
 212         status = acpi_evaluate_integer(tz->device->handle, "_TZP", NULL, &tmp);
 213         if (ACPI_FAILURE(status))
 214                 return -ENODEV;
 215
 216         tz->polling_frequency = tmp;
 217         acpi_handle_debug(tz->device->handle, "Polling frequency is %lu dS\n",
 218                           tz->polling_frequency);
 219
 220         return 0;
 221 }
 222
 223 static int acpi_thermal_set_cooling_mode(struct acpi_thermal *tz, int mode)
 224 {
 225         if (!tz)
 226                 return -EINVAL;
 227
 228         if (ACPI_FAILURE(acpi_execute_simple_method(tz->device->handle,
 229                                                     "_SCP", mode)))
 230                 return -ENODEV;
 231
 232         return 0;
 233 }
 234
 235 #define ACPI_TRIPS_CRITICAL     0x01
 236 #define ACPI_TRIPS_HOT          0x02
 237 #define ACPI_TRIPS_PASSIVE      0x04
 238 #define ACPI_TRIPS_ACTIVE       0x08
 239 #define ACPI_TRIPS_DEVICES      0x10
 240
 241 #define ACPI_TRIPS_REFRESH_THRESHOLDS   (ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE)
 242 #define ACPI_TRIPS_REFRESH_DEVICES      ACPI_TRIPS_DEVICES
 243
 244 #define ACPI_TRIPS_INIT      (ACPI_TRIPS_CRITICAL | ACPI_TRIPS_HOT |    \
 245                               ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE |  \
 246                               ACPI_TRIPS_DEVICES)
 247
 248 /*
 249  * This exception is thrown out in two cases:
 250  * 1.An invalid trip point becomes invalid or a valid trip point becomes invalid
 251  *   when re-evaluating the AML code.
 252  * 2.TODO: Devices listed in _PSL, _ALx, _TZD may change.
 253  *   We need to re-bind the cooling devices of a thermal zone when this occurs.
 254  */
 255 #define ACPI_THERMAL_TRIPS_EXCEPTION(flags, tz, str)    \
 256 do {    \
 257         if (flags != ACPI_TRIPS_INIT)   \
 258                 acpi_handle_info(tz->device->handle,    \
 259                 "ACPI thermal trip point %s changed\n"  \
 260                 "Please report to linux-acpi@vger.kernel.org\n", str); \
 261 } while (0)
 262
 263 static int acpi_thermal_trips_update(struct acpi_thermal *tz, int flag)
 264 {
 265         acpi_status status = AE_OK;
 266         unsigned long long tmp;
 267         struct acpi_handle_list devices;
 268         int valid = 0;
 269         int i;
 270
 271         /* Critical Shutdown */
 272         if (flag & ACPI_TRIPS_CRITICAL) {
 273                 status = acpi_evaluate_integer(tz->device->handle,
 274                                 "_CRT", NULL, &tmp);
 275                 tz->trips.critical.temperature = tmp;
 276                 /*
 277                  * Treat freezing temperatures as invalid as well; some
 278                  * BIOSes return really low values and cause reboots at startup.
 279                  * Below zero (Celsius) values clearly aren't right for sure..
 280                  * ... so lets discard those as invalid.
 281                  */
 282                 if (ACPI_FAILURE(status)) {
 283                         tz->trips.critical.flags.valid = 0;
 284                         acpi_handle_debug(tz->device->handle,
 285                                           "No critical threshold\n");
 286                 } else if (tmp <= 2732) {
 287                         pr_info(FW_BUG "Invalid critical threshold (%llu)\n",
 288                                 tmp);
 289                         tz->trips.critical.flags.valid = 0;
 290                 } else {
 291                         tz->trips.critical.flags.valid = 1;
 292                         acpi_handle_debug(tz->device->handle,
 293                                           "Found critical threshold [%lu]\n",
 294                                           tz->trips.critical.temperature);
 295                 }
 296                 if (tz->trips.critical.flags.valid == 1) {
 297                         if (crt == -1) {
 298                                 tz->trips.critical.flags.valid = 0;
 299                         } else if (crt > 0) {
 300                                 unsigned long crt_k = celsius_to_deci_kelvin(crt);
 301
 302                                 /*
 303                                  * Allow override critical threshold
 304                                  */
 305                                 if (crt_k > tz->trips.critical.temperature)
 306                                         pr_info("Critical threshold %d C\n", crt);
 307
 308                                 tz->trips.critical.temperature = crt_k;
 309                         }
 310                 }
 311         }
 312
 313         /* Critical Sleep (optional) */
 314         if (flag & ACPI_TRIPS_HOT) {
 315                 status = acpi_evaluate_integer(tz->device->handle,
 316                                 "_HOT", NULL, &tmp);
 317                 if (ACPI_FAILURE(status)) {
 318                         tz->trips.hot.flags.valid = 0;
 319                         acpi_handle_debug(tz->device->handle,
 320                                           "No hot threshold\n");
 321                 } else {
 322                         tz->trips.hot.temperature = tmp;
 323                         tz->trips.hot.flags.valid = 1;
 324                         acpi_handle_debug(tz->device->handle,
 325                                           "Found hot threshold [%lu]\n",
 326                                           tz->trips.hot.temperature);
 327                 }
 328         }
 329
 330         /* Passive (optional) */
 331         if (((flag & ACPI_TRIPS_PASSIVE) && tz->trips.passive.flags.valid) ||
 332                 (flag == ACPI_TRIPS_INIT)) {
 333                 valid = tz->trips.passive.flags.valid;
 334                 if (psv == -1) {
 335                         status = AE_SUPPORT;
 336                 } else if (psv > 0) {
 337                         tmp = celsius_to_deci_kelvin(psv);
 338                         status = AE_OK;
 339                 } else {
 340                         status = acpi_evaluate_integer(tz->device->handle,
 341                                 "_PSV", NULL, &tmp);
 342                 }
 343
 344                 if (ACPI_FAILURE(status))
 345                         tz->trips.passive.flags.valid = 0;
 346                 else {
 347                         tz->trips.passive.temperature = tmp;
 348                         tz->trips.passive.flags.valid = 1;
 349                         if (flag == ACPI_TRIPS_INIT) {
 350                                 status = acpi_evaluate_integer(
 351                                                 tz->device->handle, "_TC1",
 352                                                 NULL, &tmp);
 353                                 if (ACPI_FAILURE(status))
 354                                         tz->trips.passive.flags.valid = 0;
 355                                 else
 356                                         tz->trips.passive.tc1 = tmp;
 357                                 status = acpi_evaluate_integer(
 358                                                 tz->device->handle, "_TC2",
 359                                                 NULL, &tmp);
 360                                 if (ACPI_FAILURE(status))
 361                                         tz->trips.passive.flags.valid = 0;
 362                                 else
 363                                         tz->trips.passive.tc2 = tmp;
 364                                 status = acpi_evaluate_integer(
 365                                                 tz->device->handle, "_TSP",
 366                                                 NULL, &tmp);
 367                                 if (ACPI_FAILURE(status))
 368                                         tz->trips.passive.flags.valid = 0;
 369                                 else
 370                                         tz->trips.passive.tsp = tmp;
 371                         }
 372                 }
 373         }
 374         if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.passive.flags.valid) {
 375                 memset(&devices, 0, sizeof(struct acpi_handle_list));
 376                 status = acpi_evaluate_reference(tz->device->handle, "_PSL",
 377                                                         NULL, &devices);
 378                 if (ACPI_FAILURE(status)) {
 379                         acpi_handle_info(tz->device->handle,
 380                                          "Invalid passive threshold\n");
 381                         tz->trips.passive.flags.valid = 0;
 382                 }
 383                 else
 384                         tz->trips.passive.flags.valid = 1;
 385
 386                 if (memcmp(&tz->trips.passive.devices, &devices,
 387                                 sizeof(struct acpi_handle_list))) {
 388                         memcpy(&tz->trips.passive.devices, &devices,
 389                                 sizeof(struct acpi_handle_list));
 390                         ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "device");
 391                 }
 392         }
 393         if ((flag & ACPI_TRIPS_PASSIVE) || (flag & ACPI_TRIPS_DEVICES)) {
 394                 if (valid != tz->trips.passive.flags.valid)
 395                                 ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "state");
 396         }
 397
 398         /* Active (optional) */
 399         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 400                 char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
 401                 valid = tz->trips.active[i].flags.valid;
 402
 403                 if (act == -1)
 404                         break; /* disable all active trip points */
 405
 406                 if ((flag == ACPI_TRIPS_INIT) || ((flag & ACPI_TRIPS_ACTIVE) &&
 407                         tz->trips.active[i].flags.valid)) {
 408                         status = acpi_evaluate_integer(tz->device->handle,
 409                                                         name, NULL, &tmp);
 410                         if (ACPI_FAILURE(status)) {
 411                                 tz->trips.active[i].flags.valid = 0;
 412                                 if (i == 0)
 413                                         break;
 414                                 if (act <= 0)
 415                                         break;
 416                                 if (i == 1)
 417                                         tz->trips.active[0].temperature =
 418                                                 celsius_to_deci_kelvin(act);
 419                                 else
 420                                         /*
 421                                          * Don't allow override higher than
 422                                          * the next higher trip point
 423                                          */
 424                                         tz->trips.active[i - 1].temperature =
 425                                                 (tz->trips.active[i - 2].temperature <
 426                                                 celsius_to_deci_kelvin(act) ?
 427                                                 tz->trips.active[i - 2].temperature :
 428                                                 celsius_to_deci_kelvin(act));
 429                                 break;
 430                         } else {
 431                                 tz->trips.active[i].temperature = tmp;
 432                                 tz->trips.active[i].flags.valid = 1;
 433                         }
 434                 }
 435
 436                 name[2] = 'L';
 437                 if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.active[i].flags.valid ) {
 438                         memset(&devices, 0, sizeof(struct acpi_handle_list));
 439                         status = acpi_evaluate_reference(tz->device->handle,
 440                                                 name, NULL, &devices);
 441                         if (ACPI_FAILURE(status)) {
 442                                 acpi_handle_info(tz->device->handle,
 443                                                  "Invalid active%d threshold\n", i);
 444                                 tz->trips.active[i].flags.valid = 0;
 445                         }
 446                         else
 447                                 tz->trips.active[i].flags.valid = 1;
 448
 449                         if (memcmp(&tz->trips.active[i].devices, &devices,
 450                                         sizeof(struct acpi_handle_list))) {
 451                                 memcpy(&tz->trips.active[i].devices, &devices,
 452                                         sizeof(struct acpi_handle_list));
 453                                 ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "device");
 454                         }
 455                 }
 456                 if ((flag & ACPI_TRIPS_ACTIVE) || (flag & ACPI_TRIPS_DEVICES))
 457                         if (valid != tz->trips.active[i].flags.valid)
 458                                 ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "state");
 459
 460                 if (!tz->trips.active[i].flags.valid)
 461                         break;
 462         }
 463
 464         if (flag & ACPI_TRIPS_DEVICES) {
 465                 memset(&devices, 0, sizeof(devices));
 466                 status = acpi_evaluate_reference(tz->device->handle, "_TZD",
 467                                                 NULL, &devices);
 468                 if (ACPI_SUCCESS(status)
 469                     && memcmp(&tz->devices, &devices, sizeof(devices))) {
 470                         tz->devices = devices;
 471                         ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "device");
 472                 }
 473         }
 474
 475         return 0;
 476 }
 477
 478 static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
 479 {
 480         int i, valid, ret = acpi_thermal_trips_update(tz, ACPI_TRIPS_INIT);
 481
 482         if (ret)
 483                 return ret;
 484
 485         valid = tz->trips.critical.flags.valid |
 486                 tz->trips.hot.flags.valid |
 487                 tz->trips.passive.flags.valid;
 488
 489         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
 490                 valid |= tz->trips.active[i].flags.valid;
 491
 492         if (!valid) {
 493                 pr_warn(FW_BUG "No valid trip found\n");
 494                 return -ENODEV;
 495         }
 496         return 0;
 497 }
 498
 499 /* sys I/F for generic thermal sysfs support */
 500
 501 static int thermal_get_temp(struct thermal_zone_device *thermal, int *temp)
 502 {
 503         struct acpi_thermal *tz = thermal->devdata;
 504         int result;
 505
 506         if (!tz)
 507                 return -EINVAL;
 508
 509         result = acpi_thermal_get_temperature(tz);
 510         if (result)
 511                 return result;
 512
 513         *temp = deci_kelvin_to_millicelsius_with_offset(tz->temperature,
 514                                                         tz->kelvin_offset);
 515         return 0;
 516 }
 517
 518 static int thermal_get_trip_type(struct thermal_zone_device *thermal,
 519                                  int trip, enum thermal_trip_type *type)
 520 {
 521         struct acpi_thermal *tz = thermal->devdata;
 522         int i;
 523
 524         if (!tz || trip < 0)
 525                 return -EINVAL;
 526
 527         if (tz->trips.critical.flags.valid) {
 528                 if (!trip) {
 529                         *type = THERMAL_TRIP_CRITICAL;
 530                         return 0;
 531                 }
 532                 trip--;
 533         }
 534
 535         if (tz->trips.hot.flags.valid) {
 536                 if (!trip) {
 537                         *type = THERMAL_TRIP_HOT;
 538                         return 0;
 539                 }
 540                 trip--;
 541         }
 542
 543         if (tz->trips.passive.flags.valid) {
 544                 if (!trip) {
 545                         *type = THERMAL_TRIP_PASSIVE;
 546                         return 0;
 547                 }
 548                 trip--;
 549         }
 550
 551         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
 552                 tz->trips.active[i].flags.valid; i++) {
 553                 if (!trip) {
 554                         *type = THERMAL_TRIP_ACTIVE;
 555                         return 0;
 556                 }
 557                 trip--;
 558         }
 559
 560         return -EINVAL;
 561 }
 562
 563 static int thermal_get_trip_temp(struct thermal_zone_device *thermal,
 564                                  int trip, int *temp)
 565 {
 566         struct acpi_thermal *tz = thermal->devdata;
 567         int i;
 568
 569         if (!tz || trip < 0)
 570                 return -EINVAL;
 571
 572         if (tz->trips.critical.flags.valid) {
 573                 if (!trip) {
 574                         *temp = deci_kelvin_to_millicelsius_with_offset(
 575                                 tz->trips.critical.temperature,
 576                                 tz->kelvin_offset);
 577                         return 0;
 578                 }
 579                 trip--;
 580         }
 581
 582         if (tz->trips.hot.flags.valid) {
 583                 if (!trip) {
 584                         *temp = deci_kelvin_to_millicelsius_with_offset(
 585                                 tz->trips.hot.temperature,
 586                                 tz->kelvin_offset);
 587                         return 0;
 588                 }
 589                 trip--;
 590         }
 591
 592         if (tz->trips.passive.flags.valid) {
 593                 if (!trip) {
 594                         *temp = deci_kelvin_to_millicelsius_with_offset(
 595                                 tz->trips.passive.temperature,
 596                                 tz->kelvin_offset);
 597                         return 0;
 598                 }
 599                 trip--;
 600         }
 601
 602         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
 603                 tz->trips.active[i].flags.valid; i++) {
 604                 if (!trip) {
 605                         *temp = deci_kelvin_to_millicelsius_with_offset(
 606                                 tz->trips.active[i].temperature,
 607                                 tz->kelvin_offset);
 608                         return 0;
 609                 }
 610                 trip--;
 611         }
 612
 613         return -EINVAL;
 614 }
 615
 616 static int thermal_get_crit_temp(struct thermal_zone_device *thermal,
 617                                 int *temperature)
 618 {
 619         struct acpi_thermal *tz = thermal->devdata;
 620
 621         if (tz->trips.critical.flags.valid) {
 622                 *temperature = deci_kelvin_to_millicelsius_with_offset(
 623                                 tz->trips.critical.temperature,
 624                                 tz->kelvin_offset);
 625                 return 0;
 626         } else
 627                 return -EINVAL;
 628 }
 629
 630 static int thermal_get_trend(struct thermal_zone_device *thermal,
 631                                 int trip, enum thermal_trend *trend)
 632 {
 633         struct acpi_thermal *tz = thermal->devdata;
 634         enum thermal_trip_type type;
 635         int i;
 636
 637         if (thermal_get_trip_type(thermal, trip, &type))
 638                 return -EINVAL;
 639
 640         if (type == THERMAL_TRIP_ACTIVE) {
 641                 int trip_temp;
 642                 int temp = deci_kelvin_to_millicelsius_with_offset(
 643                                         tz->temperature, tz->kelvin_offset);
 644                 if (thermal_get_trip_temp(thermal, trip, &trip_temp))
 645                         return -EINVAL;
 646
 647                 if (temp > trip_temp) {
 648                         *trend = THERMAL_TREND_RAISING;
 649                         return 0;
 650                 } else {
 651                         /* Fall back on default trend */
 652                         return -EINVAL;
 653                 }
 654         }
 655
 656         /*
 657          * tz->temperature has already been updated by generic thermal layer,
 658          * before this callback being invoked
 659          */
 660         i = (tz->trips.passive.tc1 * (tz->temperature - tz->last_temperature))
 661                 + (tz->trips.passive.tc2
 662                 * (tz->temperature - tz->trips.passive.temperature));
 663
 664         if (i > 0)
 665                 *trend = THERMAL_TREND_RAISING;
 666         else if (i < 0)
 667                 *trend = THERMAL_TREND_DROPPING;
 668         else
 669                 *trend = THERMAL_TREND_STABLE;
 670         return 0;
 671 }
 672
 673 static void acpi_thermal_zone_device_hot(struct thermal_zone_device *thermal)
 674 {
 675         struct acpi_thermal *tz = thermal->devdata;
 676
 677         acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
 678                                         dev_name(&tz->device->dev),
 679                                         ACPI_THERMAL_NOTIFY_HOT, 1);
 680 }
 681
 682 static void acpi_thermal_zone_device_critical(struct thermal_zone_device *thermal)
 683 {
 684         struct acpi_thermal *tz = thermal->devdata;
 685
 686         acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
 687                                         dev_name(&tz->device->dev),
 688                                         ACPI_THERMAL_NOTIFY_CRITICAL, 1);
 689
 690         thermal_zone_device_critical(thermal);
 691 }
 692
 693 static int acpi_thermal_cooling_device_cb(struct thermal_zone_device *thermal,
 694                                         struct thermal_cooling_device *cdev,
 695                                         bool bind)
 696 {
 697         struct acpi_device *device = cdev->devdata;
 698         struct acpi_thermal *tz = thermal->devdata;
 699         struct acpi_device *dev;
 700         acpi_handle handle;
 701         int i;
 702         int j;
 703         int trip = -1;
 704         int result = 0;
 705
 706         if (tz->trips.critical.flags.valid)
 707                 trip++;
 708
 709         if (tz->trips.hot.flags.valid)
 710                 trip++;
 711
 712         if (tz->trips.passive.flags.valid) {
 713                 trip++;
 714                 for (i = 0; i < tz->trips.passive.devices.count;
 715                     i++) {
 716                         handle = tz->trips.passive.devices.handles[i];
 717                         dev = acpi_fetch_acpi_dev(handle);
 718                         if (dev != device)
 719                                 continue;
 720                         if (bind)
 721                                 result =
 722                                         thermal_zone_bind_cooling_device
 723                                         (thermal, trip, cdev,
 724                                          THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
 725                                          THERMAL_WEIGHT_DEFAULT);
 726                         else
 727                                 result =
 728                                         thermal_zone_unbind_cooling_device
 729                                         (thermal, trip, cdev);
 730                         if (result)
 731                                 goto failed;
 732                 }
 733         }
 734
 735         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 736                 if (!tz->trips.active[i].flags.valid)
 737                         break;
 738                 trip++;
 739                 for (j = 0;
 740                     j < tz->trips.active[i].devices.count;
 741                     j++) {
 742                         handle = tz->trips.active[i].devices.handles[j];
 743                         dev = acpi_fetch_acpi_dev(handle);
 744                         if (dev != device)
 745                                 continue;
 746                         if (bind)
 747                                 result = thermal_zone_bind_cooling_device
 748                                         (thermal, trip, cdev,
 749                                          THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
 750                                          THERMAL_WEIGHT_DEFAULT);
 751                         else
 752                                 result = thermal_zone_unbind_cooling_device
 753                                         (thermal, trip, cdev);
 754                         if (result)
 755                                 goto failed;
 756                 }
 757         }
 758
 759 failed:
 760         return result;
 761 }
 762
 763 static int
 764 acpi_thermal_bind_cooling_device(struct thermal_zone_device *thermal,
 765                                         struct thermal_cooling_device *cdev)
 766 {
 767         return acpi_thermal_cooling_device_cb(thermal, cdev, true);
 768 }
 769
 770 static int
 771 acpi_thermal_unbind_cooling_device(struct thermal_zone_device *thermal,
 772                                         struct thermal_cooling_device *cdev)
 773 {
 774         return acpi_thermal_cooling_device_cb(thermal, cdev, false);
 775 }
 776
 777 static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
 778         .bind = acpi_thermal_bind_cooling_device,
 779         .unbind = acpi_thermal_unbind_cooling_device,
 780         .get_temp = thermal_get_temp,
 781         .get_trip_type = thermal_get_trip_type,
 782         .get_trip_temp = thermal_get_trip_temp,
 783         .get_crit_temp = thermal_get_crit_temp,
 784         .get_trend = thermal_get_trend,
 785         .hot = acpi_thermal_zone_device_hot,
 786         .critical = acpi_thermal_zone_device_critical,
 787 };
 788
 789 static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
 790 {
 791         int trips = 0;
 792         int result;
 793         acpi_status status;
 794         int i;
 795
 796         if (tz->trips.critical.flags.valid)
 797                 trips++;
 798
 799         if (tz->trips.hot.flags.valid)
 800                 trips++;
 801
 802         if (tz->trips.passive.flags.valid)
 803                 trips++;
 804
 805         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
 806                         tz->trips.active[i].flags.valid; i++, trips++);
 807
 808         if (tz->trips.passive.flags.valid)
 809                 tz->thermal_zone =
 810                         thermal_zone_device_register("acpitz", trips, 0, tz,
 811                                                 &acpi_thermal_zone_ops, NULL,
 812                                                      tz->trips.passive.tsp*100,
 813                                                      tz->polling_frequency*100);
 814         else
 815                 tz->thermal_zone =
 816                         thermal_zone_device_register("acpitz", trips, 0, tz,
 817                                                 &acpi_thermal_zone_ops, NULL,
 818                                                 0, tz->polling_frequency*100);
 819         if (IS_ERR(tz->thermal_zone))
 820                 return -ENODEV;
 821
 822         result = sysfs_create_link(&tz->device->dev.kobj,
 823                                    &tz->thermal_zone->device.kobj, "thermal_zone");
 824         if (result)
 825                 goto unregister_tzd;
 826
 827         result = sysfs_create_link(&tz->thermal_zone->device.kobj,
 828                                    &tz->device->dev.kobj, "device");
 829         if (result)
 830                 goto remove_tz_link;
 831
 832         status =  acpi_bus_attach_private_data(tz->device->handle,
 833                                                tz->thermal_zone);
 834         if (ACPI_FAILURE(status)) {
 835                 result = -ENODEV;
 836                 goto remove_dev_link;
 837         }
 838
 839         result = thermal_zone_device_enable(tz->thermal_zone);
 840         if (result)
 841                 goto acpi_bus_detach;
 842
 843         dev_info(&tz->device->dev, "registered as thermal_zone%d\n",
 844                  tz->thermal_zone->id);
 845
 846         return 0;
 847
 848 acpi_bus_detach:
 849         acpi_bus_detach_private_data(tz->device->handle);
 850 remove_dev_link:
 851         sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
 852 remove_tz_link:
 853         sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
 854 unregister_tzd:
 855         thermal_zone_device_unregister(tz->thermal_zone);
 856
 857         return result;
 858 }
 859
 860 static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
 861 {
 862         sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
 863         sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
 864         thermal_zone_device_unregister(tz->thermal_zone);
 865         tz->thermal_zone = NULL;
 866         acpi_bus_detach_private_data(tz->device->handle);
 867 }
 868
 869
 870 /* --------------------------------------------------------------------------
 871                                  Driver Interface
 872    -------------------------------------------------------------------------- */
 873
 874 static void acpi_queue_thermal_check(struct acpi_thermal *tz)
 875 {
 876         if (!work_pending(&tz->thermal_check_work))
 877                 queue_work(acpi_thermal_pm_queue, &tz->thermal_check_work);
 878 }
 879
 880 static void acpi_thermal_notify(struct acpi_device *device, u32 event)
 881 {
 882         struct acpi_thermal *tz = acpi_driver_data(device);
 883
 884
 885         if (!tz)
 886                 return;
 887
 888         switch (event) {
 889         case ACPI_THERMAL_NOTIFY_TEMPERATURE:
 890                 acpi_queue_thermal_check(tz);
 891                 break;
 892         case ACPI_THERMAL_NOTIFY_THRESHOLDS:
 893                 acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_THRESHOLDS);
 894                 acpi_queue_thermal_check(tz);
 895                 acpi_bus_generate_netlink_event(device->pnp.device_class,
 896                                                   dev_name(&device->dev), event, 0);
 897                 break;
 898         case ACPI_THERMAL_NOTIFY_DEVICES:
 899                 acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_DEVICES);
 900                 acpi_queue_thermal_check(tz);
 901                 acpi_bus_generate_netlink_event(device->pnp.device_class,
 902                                                   dev_name(&device->dev), event, 0);
 903                 break;
 904         default:
 905                 acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
 906                                   event);
 907                 break;
 908         }
 909 }
 910
 911 /*
 912  * On some platforms, the AML code has dependency about
 913  * the evaluating order of _TMP and _CRT/_HOT/_PSV/_ACx.
 914  * 1. On HP Pavilion G4-1016tx, _TMP must be invoked after
 915  *    /_CRT/_HOT/_PSV/_ACx, or else system will be power off.
 916  * 2. On HP Compaq 6715b/6715s, the return value of _PSV is 0
 917  *    if _TMP has never been evaluated.
 918  *
 919  * As this dependency is totally transparent to OS, evaluate
 920  * all of them once, in the order of _CRT/_HOT/_PSV/_ACx,
 921  * _TMP, before they are actually used.
 922  */
 923 static void acpi_thermal_aml_dependency_fix(struct acpi_thermal *tz)
 924 {
 925         acpi_handle handle = tz->device->handle;
 926         unsigned long long value;
 927         int i;
 928
 929         acpi_evaluate_integer(handle, "_CRT", NULL, &value);
 930         acpi_evaluate_integer(handle, "_HOT", NULL, &value);
 931         acpi_evaluate_integer(handle, "_PSV", NULL, &value);
 932         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 933                 char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
 934                 acpi_status status;
 935
 936                 status = acpi_evaluate_integer(handle, name, NULL, &value);
 937                 if (status == AE_NOT_FOUND)
 938                         break;
 939         }
 940         acpi_evaluate_integer(handle, "_TMP", NULL, &value);
 941 }
 942
 943 static int acpi_thermal_get_info(struct acpi_thermal *tz)
 944 {
 945         int result = 0;
 946
 947
 948         if (!tz)
 949                 return -EINVAL;
 950
 951         acpi_thermal_aml_dependency_fix(tz);
 952
 953         /* Get trip points [_CRT, _PSV, etc.] (required) */
 954         result = acpi_thermal_get_trip_points(tz);
 955         if (result)
 956                 return result;
 957
 958         /* Get temperature [_TMP] (required) */
 959         result = acpi_thermal_get_temperature(tz);
 960         if (result)
 961                 return result;
 962
 963         /* Set the cooling mode [_SCP] to active cooling (default) */
 964         result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
 965         if (!result)
 966                 tz->flags.cooling_mode = 1;
 967
 968         /* Get default polling frequency [_TZP] (optional) */
 969         if (tzp)
 970                 tz->polling_frequency = tzp;
 971         else
 972                 acpi_thermal_get_polling_frequency(tz);
 973
 974         return 0;
 975 }
 976
 977 /*
 978  * The exact offset between Kelvin and degree Celsius is 273.15. However ACPI
 979  * handles temperature values with a single decimal place. As a consequence,
 980  * some implementations use an offset of 273.1 and others use an offset of
 981  * 273.2. Try to find out which one is being used, to present the most
 982  * accurate and visually appealing number.
 983  *
 984  * The heuristic below should work for all ACPI thermal zones which have a
 985  * critical trip point with a value being a multiple of 0.5 degree Celsius.
 986  */
 987 static void acpi_thermal_guess_offset(struct acpi_thermal *tz)
 988 {
 989         if (tz->trips.critical.flags.valid &&
 990             (tz->trips.critical.temperature % 5) == 1)
 991                 tz->kelvin_offset = 273100;
 992         else
 993                 tz->kelvin_offset = 273200;
 994 }
 995
 996 static void acpi_thermal_check_fn(struct work_struct *work)
 997 {
 998         struct acpi_thermal *tz = container_of(work, struct acpi_thermal,
 999                                                thermal_check_work);
1000
1001         /*
1002          * In general, it is not sufficient to check the pending bit, because
1003          * subsequent instances of this function may be queued after one of them
1004          * has started running (e.g. if _TMP sleeps).  Avoid bailing out if just
1005          * one of them is running, though, because it may have done the actual
1006          * check some time ago, so allow at least one of them to block on the
1007          * mutex while another one is running the update.
1008          */
1009         if (!refcount_dec_not_one(&tz->thermal_check_count))
1010                 return;
1011
1012         mutex_lock(&tz->thermal_check_lock);
1013
1014         thermal_zone_device_update(tz->thermal_zone, THERMAL_EVENT_UNSPECIFIED);
1015
1016         refcount_inc(&tz->thermal_check_count);
1017
1018         mutex_unlock(&tz->thermal_check_lock);
1019 }
1020
1021 static int acpi_thermal_add(struct acpi_device *device)
1022 {
1023         int result = 0;
1024         struct acpi_thermal *tz = NULL;
1025
1026
1027         if (!device)
1028                 return -EINVAL;
1029
1030         tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
1031         if (!tz)
1032                 return -ENOMEM;
1033
1034         tz->device = device;
1035         strcpy(tz->name, device->pnp.bus_id);
1036         strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
1037         strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
1038         device->driver_data = tz;
1039
1040         result = acpi_thermal_get_info(tz);
1041         if (result)
1042                 goto free_memory;
1043
1044         acpi_thermal_guess_offset(tz);
1045
1046         result = acpi_thermal_register_thermal_zone(tz);
1047         if (result)
1048                 goto free_memory;
1049
1050         refcount_set(&tz->thermal_check_count, 3);
1051         mutex_init(&tz->thermal_check_lock);
1052         INIT_WORK(&tz->thermal_check_work, acpi_thermal_check_fn);
1053
1054         pr_info("%s [%s] (%ld C)\n", acpi_device_name(device),
1055                 acpi_device_bid(device), deci_kelvin_to_celsius(tz->temperature));
1056         goto end;
1057
1058 free_memory:
1059         kfree(tz);
1060 end:
1061         return result;
1062 }
1063
1064 static int acpi_thermal_remove(struct acpi_device *device)
1065 {
1066         struct acpi_thermal *tz = NULL;
1067
1068         if (!device || !acpi_driver_data(device))
1069                 return -EINVAL;
1070
1071         flush_workqueue(acpi_thermal_pm_queue);
1072         tz = acpi_driver_data(device);
1073
1074         acpi_thermal_unregister_thermal_zone(tz);
1075         kfree(tz);
1076         return 0;
1077 }
1078
1079 #ifdef CONFIG_PM_SLEEP
1080 static int acpi_thermal_suspend(struct device *dev)
1081 {
1082         /* Make sure the previously queued thermal check work has been done */
1083         flush_workqueue(acpi_thermal_pm_queue);
1084         return 0;
1085 }
1086
1087 static int acpi_thermal_resume(struct device *dev)
1088 {
1089         struct acpi_thermal *tz;
1090         int i, j, power_state, result;
1091
1092         if (!dev)
1093                 return -EINVAL;
1094
1095         tz = acpi_driver_data(to_acpi_device(dev));
1096         if (!tz)
1097                 return -EINVAL;
1098
1099         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1100                 if (!tz->trips.active[i].flags.valid)
1101                         break;
1102                 tz->trips.active[i].flags.enabled = 1;
1103                 for (j = 0; j < tz->trips.active[i].devices.count; j++) {
1104                         result = acpi_bus_update_power(
1105                                         tz->trips.active[i].devices.handles[j],
1106                                         &power_state);
1107                         if (result || (power_state != ACPI_STATE_D0)) {
1108                                 tz->trips.active[i].flags.enabled = 0;
1109                                 break;
1110                         }
1111                 }
1112                 tz->state.active |= tz->trips.active[i].flags.enabled;
1113         }
1114
1115         acpi_queue_thermal_check(tz);
1116
1117         return AE_OK;
1118 }
1119 #endif
1120
1121 static int thermal_act(const struct dmi_system_id *d) {
1122
1123         if (act == 0) {
1124                 pr_notice("%s detected: disabling all active thermal trip points\n",
1125                           d->ident);
1126                 act = -1;
1127         }
1128         return 0;
1129 }
1130 static int thermal_nocrt(const struct dmi_system_id *d) {
1131
1132         pr_notice("%s detected: disabling all critical thermal trip point actions.\n",
1133                   d->ident);
1134         nocrt = 1;
1135         return 0;
1136 }
1137 static int thermal_tzp(const struct dmi_system_id *d) {
1138
1139         if (tzp == 0) {
1140                 pr_notice("%s detected: enabling thermal zone polling\n",
1141                           d->ident);
1142                 tzp = 300;      /* 300 dS = 30 Seconds */
1143         }
1144         return 0;
1145 }
1146 static int thermal_psv(const struct dmi_system_id *d) {
1147
1148         if (psv == 0) {
1149                 pr_notice("%s detected: disabling all passive thermal trip points\n",
1150                           d->ident);
1151                 psv = -1;
1152         }
1153         return 0;
1154 }
1155
1156 static const struct dmi_system_id thermal_dmi_table[] __initconst = {
1157         /*
1158          * Award BIOS on this AOpen makes thermal control almost worthless.
1159          * http://bugzilla.kernel.org/show_bug.cgi?id=8842
1160          */
1161         {
1162          .callback = thermal_act,
1163          .ident = "AOpen i915GMm-HFS",
1164          .matches = {
1165                 DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1166                 DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1167                 },
1168         },
1169         {
1170          .callback = thermal_psv,
1171          .ident = "AOpen i915GMm-HFS",
1172          .matches = {
1173                 DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1174                 DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1175                 },
1176         },
1177         {
1178          .callback = thermal_tzp,
1179          .ident = "AOpen i915GMm-HFS",
1180          .matches = {
1181                 DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1182                 DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1183                 },
1184         },
1185         {
1186          .callback = thermal_nocrt,
1187          .ident = "Gigabyte GA-7ZX",
1188          .matches = {
1189                 DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
1190                 DMI_MATCH(DMI_BOARD_NAME, "7ZX"),
1191                 },
1192         },
1193         {}
1194 };
1195
1196 static int __init acpi_thermal_init(void)
1197 {
1198         int result = 0;
1199
1200         dmi_check_system(thermal_dmi_table);
1201
1202         if (off) {
1203                 pr_notice("thermal control disabled\n");
1204                 return -ENODEV;
1205         }
1206
1207         acpi_thermal_pm_queue = alloc_workqueue("acpi_thermal_pm",
1208                                                 WQ_HIGHPRI | WQ_MEM_RECLAIM, 0);
1209         if (!acpi_thermal_pm_queue)
1210                 return -ENODEV;
1211
1212         result = acpi_bus_register_driver(&acpi_thermal_driver);
1213         if (result < 0) {
1214                 destroy_workqueue(acpi_thermal_pm_queue);
1215                 return -ENODEV;
1216         }
1217
1218         return 0;
1219 }
1220
1221 static void __exit acpi_thermal_exit(void)
1222 {
1223         acpi_bus_unregister_driver(&acpi_thermal_driver);
1224         destroy_workqueue(acpi_thermal_pm_queue);
1225
1226         return;
1227 }
1228
1229 module_init(acpi_thermal_init);
1230 module_exit(acpi_thermal_exit);