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