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