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 #define ACPI_THERMAL_TRIP_PASSIVE       (-1)
  47
  48 /*
  49  * This exception is thrown out in two cases:
  50  * 1.An invalid trip point becomes invalid or a valid trip point becomes invalid
  51  *   when re-evaluating the AML code.
  52  * 2.TODO: Devices listed in _PSL, _ALx, _TZD may change.
  53  *   We need to re-bind the cooling devices of a thermal zone when this occurs.
  54  */
  55 #define ACPI_THERMAL_TRIPS_EXCEPTION(tz, str) \
  56 do { \
  57         acpi_handle_info(tz->device->handle, \
  58                          "ACPI thermal trip point %s changed\n" \
  59                          "Please report to linux-acpi@vger.kernel.org\n", str); \
  60 } while (0)
  61
  62 static int act;
  63 module_param(act, int, 0644);
  64 MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");
  65
  66 static int crt;
  67 module_param(crt, int, 0644);
  68 MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");
  69
  70 static int tzp;
  71 module_param(tzp, int, 0444);
  72 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
  73
  74 static int off;
  75 module_param(off, int, 0);
  76 MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
  77
  78 static int psv;
  79 module_param(psv, int, 0644);
  80 MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");
  81
  82 static struct workqueue_struct *acpi_thermal_pm_queue;
  83
  84 struct acpi_thermal_trip {
  85         unsigned long temp_dk;
  86         struct acpi_handle_list devices;
  87 };
  88
  89 struct acpi_thermal_passive {
  90         struct acpi_thermal_trip trip;
  91         unsigned long tc1;
  92         unsigned long tc2;
  93         unsigned long tsp;
  94 };
  95
  96 struct acpi_thermal_active {
  97         struct acpi_thermal_trip trip;
  98 };
  99
 100 struct acpi_thermal_trips {
 101         struct acpi_thermal_passive passive;
 102         struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
 103 };
 104
 105 struct acpi_thermal {
 106         struct acpi_device *device;
 107         acpi_bus_id name;
 108         unsigned long temp_dk;
 109         unsigned long last_temp_dk;
 110         unsigned long polling_frequency;
 111         volatile u8 zombie;
 112         struct acpi_thermal_trips trips;
 113         struct thermal_trip *trip_table;
 114         struct thermal_zone_device *thermal_zone;
 115         int kelvin_offset;      /* in millidegrees */
 116         struct work_struct thermal_check_work;
 117         struct mutex thermal_check_lock;
 118         refcount_t thermal_check_count;
 119 };
 120
 121 /* --------------------------------------------------------------------------
 122                              Thermal Zone Management
 123    -------------------------------------------------------------------------- */
 124
 125 static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
 126 {
 127         acpi_status status = AE_OK;
 128         unsigned long long tmp;
 129
 130         if (!tz)
 131                 return -EINVAL;
 132
 133         tz->last_temp_dk = tz->temp_dk;
 134
 135         status = acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tmp);
 136         if (ACPI_FAILURE(status))
 137                 return -ENODEV;
 138
 139         tz->temp_dk = tmp;
 140
 141         acpi_handle_debug(tz->device->handle, "Temperature is %lu dK\n",
 142                           tz->temp_dk);
 143
 144         return 0;
 145 }
 146
 147 static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
 148 {
 149         acpi_status status = AE_OK;
 150         unsigned long long tmp;
 151
 152         if (!tz)
 153                 return -EINVAL;
 154
 155         status = acpi_evaluate_integer(tz->device->handle, "_TZP", NULL, &tmp);
 156         if (ACPI_FAILURE(status))
 157                 return -ENODEV;
 158
 159         tz->polling_frequency = tmp;
 160         acpi_handle_debug(tz->device->handle, "Polling frequency is %lu dS\n",
 161                           tz->polling_frequency);
 162
 163         return 0;
 164 }
 165
 166 static int acpi_thermal_temp(struct acpi_thermal *tz, int temp_deci_k)
 167 {
 168         if (temp_deci_k == THERMAL_TEMP_INVALID)
 169                 return THERMAL_TEMP_INVALID;
 170
 171         return deci_kelvin_to_millicelsius_with_offset(temp_deci_k,
 172                                                        tz->kelvin_offset);
 173 }
 174
 175 static bool acpi_thermal_trip_valid(struct acpi_thermal_trip *acpi_trip)
 176 {
 177         return acpi_trip->temp_dk != THERMAL_TEMP_INVALID;
 178 }
 179
 180 static int active_trip_index(struct acpi_thermal *tz,
 181                              struct acpi_thermal_trip *acpi_trip)
 182 {
 183         struct acpi_thermal_active *active;
 184
 185         active = container_of(acpi_trip, struct acpi_thermal_active, trip);
 186         return active - tz->trips.active;
 187 }
 188
 189 static long get_passive_temp(struct acpi_thermal *tz)
 190 {
 191         unsigned long long tmp;
 192         acpi_status status;
 193
 194         status = acpi_evaluate_integer(tz->device->handle, "_PSV", NULL, &tmp);
 195         if (ACPI_FAILURE(status))
 196                 return THERMAL_TEMP_INVALID;
 197
 198         return tmp;
 199 }
 200
 201 static long get_active_temp(struct acpi_thermal *tz, int index)
 202 {
 203         char method[] = { '_', 'A', 'C', '0' + index, '\0' };
 204         unsigned long long tmp;
 205         acpi_status status;
 206
 207         status = acpi_evaluate_integer(tz->device->handle, method, NULL, &tmp);
 208         if (ACPI_FAILURE(status))
 209                 return THERMAL_TEMP_INVALID;
 210
 211         /*
 212          * If an override has been provided, apply it so there are no active
 213          * trips with thresholds greater than the override.
 214          */
 215         if (act > 0) {
 216                 unsigned long long override = celsius_to_deci_kelvin(act);
 217
 218                 if (tmp > override)
 219                         tmp = override;
 220         }
 221         return tmp;
 222 }
 223
 224 static void acpi_thermal_update_trip(struct acpi_thermal *tz,
 225                                      const struct thermal_trip *trip)
 226 {
 227         struct acpi_thermal_trip *acpi_trip = trip->priv;
 228
 229         if (trip->type == THERMAL_TRIP_PASSIVE) {
 230                 if (psv > 0)
 231                         return;
 232
 233                 acpi_trip->temp_dk = get_passive_temp(tz);
 234         } else {
 235                 int index = active_trip_index(tz, acpi_trip);
 236
 237                 acpi_trip->temp_dk = get_active_temp(tz, index);
 238         }
 239
 240         if (!acpi_thermal_trip_valid(acpi_trip))
 241                 ACPI_THERMAL_TRIPS_EXCEPTION(tz, "state");
 242 }
 243
 244 static bool update_trip_devices(struct acpi_thermal *tz,
 245                                 struct acpi_thermal_trip *acpi_trip,
 246                                 int index, bool compare)
 247 {
 248         struct acpi_handle_list devices = { 0 };
 249         char method[] = "_PSL";
 250         acpi_status status;
 251
 252         if (index != ACPI_THERMAL_TRIP_PASSIVE) {
 253                 method[1] = 'A';
 254                 method[2] = 'L';
 255                 method[3] = '0' + index;
 256         }
 257
 258         status = acpi_evaluate_reference(tz->device->handle, method, NULL, &devices);
 259         if (ACPI_FAILURE(status)) {
 260                 acpi_handle_info(tz->device->handle, "%s evaluation failure\n", method);
 261                 return false;
 262         }
 263
 264         if (acpi_handle_list_equal(&acpi_trip->devices, &devices)) {
 265                 acpi_handle_list_free(&devices);
 266                 return true;
 267         }
 268
 269         if (compare)
 270                 ACPI_THERMAL_TRIPS_EXCEPTION(tz, "device");
 271
 272         acpi_handle_list_replace(&acpi_trip->devices, &devices);
 273         return true;
 274 }
 275
 276 static void acpi_thermal_update_trip_devices(struct acpi_thermal *tz,
 277                                              const struct thermal_trip *trip)
 278 {
 279         struct acpi_thermal_trip *acpi_trip = trip->priv;
 280         int index = trip->type == THERMAL_TRIP_PASSIVE ?
 281                         ACPI_THERMAL_TRIP_PASSIVE : active_trip_index(tz, acpi_trip);
 282
 283         if (update_trip_devices(tz, acpi_trip, index, true))
 284                 return;
 285
 286         acpi_trip->temp_dk = THERMAL_TEMP_INVALID;
 287         ACPI_THERMAL_TRIPS_EXCEPTION(tz, "state");
 288 }
 289
 290 struct adjust_trip_data {
 291         struct acpi_thermal *tz;
 292         u32 event;
 293 };
 294
 295 static int acpi_thermal_adjust_trip(struct thermal_trip *trip, void *data)
 296 {
 297         struct acpi_thermal_trip *acpi_trip = trip->priv;
 298         struct adjust_trip_data *atd = data;
 299         struct acpi_thermal *tz = atd->tz;
 300
 301         if (!acpi_trip || !acpi_thermal_trip_valid(acpi_trip))
 302                 return 0;
 303
 304         if (atd->event == ACPI_THERMAL_NOTIFY_THRESHOLDS)
 305                 acpi_thermal_update_trip(tz, trip);
 306         else
 307                 acpi_thermal_update_trip_devices(tz, trip);
 308
 309         if (acpi_thermal_trip_valid(acpi_trip))
 310                 trip->temperature = acpi_thermal_temp(tz, acpi_trip->temp_dk);
 311         else
 312                 trip->temperature = THERMAL_TEMP_INVALID;
 313
 314         return 0;
 315 }
 316
 317 static void acpi_queue_thermal_check(struct acpi_thermal *tz)
 318 {
 319         if (!work_pending(&tz->thermal_check_work))
 320                 queue_work(acpi_thermal_pm_queue, &tz->thermal_check_work);
 321 }
 322
 323 static void acpi_thermal_trips_update(struct acpi_thermal *tz, u32 event)
 324 {
 325         struct adjust_trip_data atd = { .tz = tz, .event = event };
 326         struct acpi_device *adev = tz->device;
 327
 328         /*
 329          * Use thermal_zone_for_each_trip() to carry out the trip points
 330          * update, so as to protect thermal_get_trend() from getting stale
 331          * trip point temperatures and to prevent thermal_zone_device_update()
 332          * invoked from acpi_thermal_check_fn() from producing inconsistent
 333          * results.
 334          */
 335         thermal_zone_for_each_trip(tz->thermal_zone,
 336                                    acpi_thermal_adjust_trip, &atd);
 337         acpi_queue_thermal_check(tz);
 338         acpi_bus_generate_netlink_event(adev->pnp.device_class,
 339                                         dev_name(&adev->dev), event, 0);
 340 }
 341
 342 static long acpi_thermal_get_critical_trip(struct acpi_thermal *tz)
 343 {
 344         unsigned long long tmp;
 345         acpi_status status;
 346
 347         if (crt > 0) {
 348                 tmp = celsius_to_deci_kelvin(crt);
 349                 goto set;
 350         }
 351         if (crt == -1) {
 352                 acpi_handle_debug(tz->device->handle, "Critical threshold disabled\n");
 353                 return THERMAL_TEMP_INVALID;
 354         }
 355
 356         status = acpi_evaluate_integer(tz->device->handle, "_CRT", NULL, &tmp);
 357         if (ACPI_FAILURE(status)) {
 358                 acpi_handle_debug(tz->device->handle, "No critical threshold\n");
 359                 return THERMAL_TEMP_INVALID;
 360         }
 361         if (tmp <= 2732) {
 362                 /*
 363                  * Below zero (Celsius) values clearly aren't right for sure,
 364                  * so discard them as invalid.
 365                  */
 366                 pr_info(FW_BUG "Invalid critical threshold (%llu)\n", tmp);
 367                 return THERMAL_TEMP_INVALID;
 368         }
 369
 370 set:
 371         acpi_handle_debug(tz->device->handle, "Critical threshold [%llu]\n", tmp);
 372         return tmp;
 373 }
 374
 375 static long acpi_thermal_get_hot_trip(struct acpi_thermal *tz)
 376 {
 377         unsigned long long tmp;
 378         acpi_status status;
 379
 380         status = acpi_evaluate_integer(tz->device->handle, "_HOT", NULL, &tmp);
 381         if (ACPI_FAILURE(status)) {
 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 [%llu]\n", tmp);
 387         return tmp;
 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, "_TSP", NULL, &tmp);
 408         if (ACPI_FAILURE(status))
 409                 return false;
 410
 411         tz->trips.passive.tsp = tmp;
 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 int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
 456 {
 457         unsigned int count = 0;
 458         int i;
 459
 460         if (acpi_thermal_init_trip(tz, ACPI_THERMAL_TRIP_PASSIVE))
 461                 count++;
 462
 463         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 464                 if (acpi_thermal_init_trip(tz, i))
 465                         count++;
 466                 else
 467                         break;
 468
 469         }
 470
 471         while (++i < ACPI_THERMAL_MAX_ACTIVE)
 472                 tz->trips.active[i].trip.temp_dk = THERMAL_TEMP_INVALID;
 473
 474         return count;
 475 }
 476
 477 /* sys I/F for generic thermal sysfs support */
 478
 479 static int thermal_get_temp(struct thermal_zone_device *thermal, int *temp)
 480 {
 481         struct acpi_thermal *tz = thermal_zone_device_priv(thermal);
 482         int result;
 483
 484         if (!tz)
 485                 return -EINVAL;
 486
 487         result = acpi_thermal_get_temperature(tz);
 488         if (result)
 489                 return result;
 490
 491         *temp = deci_kelvin_to_millicelsius_with_offset(tz->temp_dk,
 492                                                         tz->kelvin_offset);
 493         return 0;
 494 }
 495
 496 static int thermal_get_trend(struct thermal_zone_device *thermal,
 497                              const struct thermal_trip *trip,
 498                              enum thermal_trend *trend)
 499 {
 500         struct acpi_thermal *tz = thermal_zone_device_priv(thermal);
 501         struct acpi_thermal_trip *acpi_trip;
 502         int t;
 503
 504         if (!tz || !trip)
 505                 return -EINVAL;
 506
 507         acpi_trip = trip->priv;
 508         if (!acpi_trip || !acpi_thermal_trip_valid(acpi_trip))
 509                 return -EINVAL;
 510
 511         switch (trip->type) {
 512         case THERMAL_TRIP_PASSIVE:
 513                 t = tz->trips.passive.tc1 * (tz->temp_dk -
 514                                                 tz->last_temp_dk) +
 515                         tz->trips.passive.tc2 * (tz->temp_dk -
 516                                                 acpi_trip->temp_dk);
 517                 if (t > 0)
 518                         *trend = THERMAL_TREND_RAISING;
 519                 else if (t < 0)
 520                         *trend = THERMAL_TREND_DROPPING;
 521                 else
 522                         *trend = THERMAL_TREND_STABLE;
 523
 524                 return 0;
 525
 526         case THERMAL_TRIP_ACTIVE:
 527                 t = acpi_thermal_temp(tz, tz->temp_dk);
 528                 if (t <= trip->temperature)
 529                         break;
 530
 531                 *trend = THERMAL_TREND_RAISING;
 532
 533                 return 0;
 534
 535         default:
 536                 break;
 537         }
 538
 539         return -EINVAL;
 540 }
 541
 542 static void acpi_thermal_zone_device_hot(struct thermal_zone_device *thermal)
 543 {
 544         struct acpi_thermal *tz = thermal_zone_device_priv(thermal);
 545
 546         acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
 547                                         dev_name(&tz->device->dev),
 548                                         ACPI_THERMAL_NOTIFY_HOT, 1);
 549 }
 550
 551 static void acpi_thermal_zone_device_critical(struct thermal_zone_device *thermal)
 552 {
 553         struct acpi_thermal *tz = thermal_zone_device_priv(thermal);
 554
 555         acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
 556                                         dev_name(&tz->device->dev),
 557                                         ACPI_THERMAL_NOTIFY_CRITICAL, 1);
 558
 559         thermal_zone_device_critical(thermal);
 560 }
 561
 562 struct acpi_thermal_bind_data {
 563         struct thermal_zone_device *thermal;
 564         struct thermal_cooling_device *cdev;
 565         bool bind;
 566 };
 567
 568 static int bind_unbind_cdev_cb(struct thermal_trip *trip, void *arg)
 569 {
 570         struct acpi_thermal_trip *acpi_trip = trip->priv;
 571         struct acpi_thermal_bind_data *bd = arg;
 572         struct thermal_zone_device *thermal = bd->thermal;
 573         struct thermal_cooling_device *cdev = bd->cdev;
 574         struct acpi_device *cdev_adev = cdev->devdata;
 575         int i;
 576
 577         /* Skip critical and hot trips. */
 578         if (!acpi_trip)
 579                 return 0;
 580
 581         for (i = 0; i < acpi_trip->devices.count; i++) {
 582                 acpi_handle handle = acpi_trip->devices.handles[i];
 583                 struct acpi_device *adev = acpi_fetch_acpi_dev(handle);
 584
 585                 if (adev != cdev_adev)
 586                         continue;
 587
 588                 if (bd->bind) {
 589                         int ret;
 590
 591                         ret = thermal_bind_cdev_to_trip(thermal, trip, cdev,
 592                                                         THERMAL_NO_LIMIT,
 593                                                         THERMAL_NO_LIMIT,
 594                                                         THERMAL_WEIGHT_DEFAULT);
 595                         if (ret)
 596                                 return ret;
 597                 } else {
 598                         thermal_unbind_cdev_from_trip(thermal, trip, cdev);
 599                 }
 600         }
 601
 602         return 0;
 603 }
 604
 605 static int acpi_thermal_bind_unbind_cdev(struct thermal_zone_device *thermal,
 606                                          struct thermal_cooling_device *cdev,
 607                                          bool bind)
 608 {
 609         struct acpi_thermal_bind_data bd = {
 610                 .thermal = thermal, .cdev = cdev, .bind = bind
 611         };
 612
 613         return for_each_thermal_trip(thermal, bind_unbind_cdev_cb, &bd);
 614 }
 615
 616 static int
 617 acpi_thermal_bind_cooling_device(struct thermal_zone_device *thermal,
 618                                  struct thermal_cooling_device *cdev)
 619 {
 620         return acpi_thermal_bind_unbind_cdev(thermal, cdev, true);
 621 }
 622
 623 static int
 624 acpi_thermal_unbind_cooling_device(struct thermal_zone_device *thermal,
 625                                    struct thermal_cooling_device *cdev)
 626 {
 627         return acpi_thermal_bind_unbind_cdev(thermal, cdev, false);
 628 }
 629
 630 static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
 631         .bind = acpi_thermal_bind_cooling_device,
 632         .unbind = acpi_thermal_unbind_cooling_device,
 633         .get_temp = thermal_get_temp,
 634         .get_trend = thermal_get_trend,
 635         .hot = acpi_thermal_zone_device_hot,
 636         .critical = acpi_thermal_zone_device_critical,
 637 };
 638
 639 static int acpi_thermal_zone_sysfs_add(struct acpi_thermal *tz)
 640 {
 641         struct device *tzdev = thermal_zone_device(tz->thermal_zone);
 642         int ret;
 643
 644         ret = sysfs_create_link(&tz->device->dev.kobj,
 645                                 &tzdev->kobj, "thermal_zone");
 646         if (ret)
 647                 return ret;
 648
 649         ret = sysfs_create_link(&tzdev->kobj,
 650                                    &tz->device->dev.kobj, "device");
 651         if (ret)
 652                 sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
 653
 654         return ret;
 655 }
 656
 657 static void acpi_thermal_zone_sysfs_remove(struct acpi_thermal *tz)
 658 {
 659         struct device *tzdev = thermal_zone_device(tz->thermal_zone);
 660
 661         sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
 662         sysfs_remove_link(&tzdev->kobj, "device");
 663 }
 664
 665 static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz,
 666                                               unsigned int trip_count,
 667                                               int passive_delay)
 668 {
 669         int result;
 670
 671         tz->thermal_zone = thermal_zone_device_register_with_trips("acpitz",
 672                                                                    tz->trip_table,
 673                                                                    trip_count,
 674                                                                    0, tz,
 675                                                                    &acpi_thermal_zone_ops,
 676                                                                    NULL,
 677                                                                    passive_delay,
 678                                                                    tz->polling_frequency * 100);
 679         if (IS_ERR(tz->thermal_zone))
 680                 return PTR_ERR(tz->thermal_zone);
 681
 682         result = acpi_thermal_zone_sysfs_add(tz);
 683         if (result)
 684                 goto unregister_tzd;
 685
 686         result = thermal_zone_device_enable(tz->thermal_zone);
 687         if (result)
 688                 goto remove_links;
 689
 690         dev_info(&tz->device->dev, "registered as thermal_zone%d\n",
 691                  thermal_zone_device_id(tz->thermal_zone));
 692
 693         return 0;
 694
 695 remove_links:
 696         acpi_thermal_zone_sysfs_remove(tz);
 697 unregister_tzd:
 698         thermal_zone_device_unregister(tz->thermal_zone);
 699
 700         return result;
 701 }
 702
 703 static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
 704 {
 705         thermal_zone_device_disable(tz->thermal_zone);
 706         acpi_thermal_zone_sysfs_remove(tz);
 707         thermal_zone_device_unregister(tz->thermal_zone);
 708         tz->thermal_zone = NULL;
 709 }
 710
 711
 712 /* --------------------------------------------------------------------------
 713                                  Driver Interface
 714    -------------------------------------------------------------------------- */
 715
 716 static void acpi_thermal_notify(acpi_handle handle, u32 event, void *data)
 717 {
 718         struct acpi_device *device = data;
 719         struct acpi_thermal *tz = acpi_driver_data(device);
 720
 721         if (!tz)
 722                 return;
 723
 724         switch (event) {
 725         case ACPI_THERMAL_NOTIFY_TEMPERATURE:
 726                 acpi_queue_thermal_check(tz);
 727                 break;
 728         case ACPI_THERMAL_NOTIFY_THRESHOLDS:
 729         case ACPI_THERMAL_NOTIFY_DEVICES:
 730                 acpi_thermal_trips_update(tz, event);
 731                 break;
 732         default:
 733                 acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
 734                                   event);
 735                 break;
 736         }
 737 }
 738
 739 /*
 740  * On some platforms, the AML code has dependency about
 741  * the evaluating order of _TMP and _CRT/_HOT/_PSV/_ACx.
 742  * 1. On HP Pavilion G4-1016tx, _TMP must be invoked after
 743  *    /_CRT/_HOT/_PSV/_ACx, or else system will be power off.
 744  * 2. On HP Compaq 6715b/6715s, the return value of _PSV is 0
 745  *    if _TMP has never been evaluated.
 746  *
 747  * As this dependency is totally transparent to OS, evaluate
 748  * all of them once, in the order of _CRT/_HOT/_PSV/_ACx,
 749  * _TMP, before they are actually used.
 750  */
 751 static void acpi_thermal_aml_dependency_fix(struct acpi_thermal *tz)
 752 {
 753         acpi_handle handle = tz->device->handle;
 754         unsigned long long value;
 755         int i;
 756
 757         acpi_evaluate_integer(handle, "_CRT", NULL, &value);
 758         acpi_evaluate_integer(handle, "_HOT", NULL, &value);
 759         acpi_evaluate_integer(handle, "_PSV", NULL, &value);
 760         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 761                 char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
 762                 acpi_status status;
 763
 764                 status = acpi_evaluate_integer(handle, name, NULL, &value);
 765                 if (status == AE_NOT_FOUND)
 766                         break;
 767         }
 768         acpi_evaluate_integer(handle, "_TMP", NULL, &value);
 769 }
 770
 771 /*
 772  * The exact offset between Kelvin and degree Celsius is 273.15. However ACPI
 773  * handles temperature values with a single decimal place. As a consequence,
 774  * some implementations use an offset of 273.1 and others use an offset of
 775  * 273.2. Try to find out which one is being used, to present the most
 776  * accurate and visually appealing number.
 777  *
 778  * The heuristic below should work for all ACPI thermal zones which have a
 779  * critical trip point with a value being a multiple of 0.5 degree Celsius.
 780  */
 781 static void acpi_thermal_guess_offset(struct acpi_thermal *tz, long crit_temp)
 782 {
 783         if (crit_temp != THERMAL_TEMP_INVALID && crit_temp % 5 == 1)
 784                 tz->kelvin_offset = 273100;
 785         else
 786                 tz->kelvin_offset = 273200;
 787 }
 788
 789 static void acpi_thermal_check_fn(struct work_struct *work)
 790 {
 791         struct acpi_thermal *tz = container_of(work, struct acpi_thermal,
 792                                                thermal_check_work);
 793
 794         /*
 795          * In general, it is not sufficient to check the pending bit, because
 796          * subsequent instances of this function may be queued after one of them
 797          * has started running (e.g. if _TMP sleeps).  Avoid bailing out if just
 798          * one of them is running, though, because it may have done the actual
 799          * check some time ago, so allow at least one of them to block on the
 800          * mutex while another one is running the update.
 801          */
 802         if (!refcount_dec_not_one(&tz->thermal_check_count))
 803                 return;
 804
 805         mutex_lock(&tz->thermal_check_lock);
 806
 807         thermal_zone_device_update(tz->thermal_zone, THERMAL_EVENT_UNSPECIFIED);
 808
 809         refcount_inc(&tz->thermal_check_count);
 810
 811         mutex_unlock(&tz->thermal_check_lock);
 812 }
 813
 814 static void acpi_thermal_free_thermal_zone(struct acpi_thermal *tz)
 815 {
 816         int i;
 817
 818         acpi_handle_list_free(&tz->trips.passive.trip.devices);
 819         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
 820                 acpi_handle_list_free(&tz->trips.active[i].trip.devices);
 821
 822         kfree(tz);
 823 }
 824
 825 static int acpi_thermal_add(struct acpi_device *device)
 826 {
 827         struct acpi_thermal_trip *acpi_trip;
 828         struct thermal_trip *trip;
 829         struct acpi_thermal *tz;
 830         unsigned int trip_count;
 831         int crit_temp, hot_temp;
 832         int passive_delay = 0;
 833         int result;
 834         int i;
 835
 836         if (!device)
 837                 return -EINVAL;
 838
 839         tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
 840         if (!tz)
 841                 return -ENOMEM;
 842
 843         tz->device = device;
 844         strcpy(tz->name, device->pnp.bus_id);
 845         strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
 846         strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
 847         device->driver_data = tz;
 848
 849         acpi_thermal_aml_dependency_fix(tz);
 850
 851         /* Get trip points [_CRT, _PSV, etc.] (required). */
 852         trip_count = acpi_thermal_get_trip_points(tz);
 853
 854         crit_temp = acpi_thermal_get_critical_trip(tz);
 855         if (crit_temp != THERMAL_TEMP_INVALID)
 856                 trip_count++;
 857
 858         hot_temp = acpi_thermal_get_hot_trip(tz);
 859         if (hot_temp != THERMAL_TEMP_INVALID)
 860                 trip_count++;
 861
 862         if (!trip_count) {
 863                 pr_warn(FW_BUG "No valid trip points!\n");
 864                 result = -ENODEV;
 865                 goto free_memory;
 866         }
 867
 868         /* Get temperature [_TMP] (required). */
 869         result = acpi_thermal_get_temperature(tz);
 870         if (result)
 871                 goto free_memory;
 872
 873         /* Set the cooling mode [_SCP] to active cooling. */
 874         acpi_execute_simple_method(tz->device->handle, "_SCP",
 875                                    ACPI_THERMAL_MODE_ACTIVE);
 876
 877         /* Determine the default polling frequency [_TZP]. */
 878         if (tzp)
 879                 tz->polling_frequency = tzp;
 880         else
 881                 acpi_thermal_get_polling_frequency(tz);
 882
 883         acpi_thermal_guess_offset(tz, crit_temp);
 884
 885         trip = kcalloc(trip_count, sizeof(*trip), GFP_KERNEL);
 886         if (!trip) {
 887                 result = -ENOMEM;
 888                 goto free_memory;
 889         }
 890
 891         tz->trip_table = trip;
 892
 893         if (crit_temp != THERMAL_TEMP_INVALID) {
 894                 trip->type = THERMAL_TRIP_CRITICAL;
 895                 trip->temperature = acpi_thermal_temp(tz, crit_temp);
 896                 trip++;
 897         }
 898
 899         if (hot_temp != THERMAL_TEMP_INVALID) {
 900                 trip->type = THERMAL_TRIP_HOT;
 901                 trip->temperature = acpi_thermal_temp(tz, hot_temp);
 902                 trip++;
 903         }
 904
 905         acpi_trip = &tz->trips.passive.trip;
 906         if (acpi_thermal_trip_valid(acpi_trip)) {
 907                 passive_delay = tz->trips.passive.tsp * 100;
 908
 909                 trip->type = THERMAL_TRIP_PASSIVE;
 910                 trip->temperature = acpi_thermal_temp(tz, acpi_trip->temp_dk);
 911                 trip->priv = acpi_trip;
 912                 trip++;
 913         }
 914
 915         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 916                 acpi_trip =  &tz->trips.active[i].trip;
 917
 918                 if (!acpi_thermal_trip_valid(acpi_trip))
 919                         break;
 920
 921                 trip->type = THERMAL_TRIP_ACTIVE;
 922                 trip->temperature = acpi_thermal_temp(tz, acpi_trip->temp_dk);
 923                 trip->priv = acpi_trip;
 924                 trip++;
 925         }
 926
 927         result = acpi_thermal_register_thermal_zone(tz, trip_count, passive_delay);
 928         if (result)
 929                 goto free_trips;
 930
 931         refcount_set(&tz->thermal_check_count, 3);
 932         mutex_init(&tz->thermal_check_lock);
 933         INIT_WORK(&tz->thermal_check_work, acpi_thermal_check_fn);
 934
 935         pr_info("%s [%s] (%ld C)\n", acpi_device_name(device),
 936                 acpi_device_bid(device), deci_kelvin_to_celsius(tz->temp_dk));
 937
 938         result = acpi_dev_install_notify_handler(device, ACPI_DEVICE_NOTIFY,
 939                                                  acpi_thermal_notify, device);
 940         if (result)
 941                 goto flush_wq;
 942
 943         return 0;
 944
 945 flush_wq:
 946         flush_workqueue(acpi_thermal_pm_queue);
 947         acpi_thermal_unregister_thermal_zone(tz);
 948 free_trips:
 949         kfree(tz->trip_table);
 950 free_memory:
 951         acpi_thermal_free_thermal_zone(tz);
 952
 953         return result;
 954 }
 955
 956 static void acpi_thermal_remove(struct acpi_device *device)
 957 {
 958         struct acpi_thermal *tz;
 959
 960         if (!device || !acpi_driver_data(device))
 961                 return;
 962
 963         tz = acpi_driver_data(device);
 964
 965         acpi_dev_remove_notify_handler(device, ACPI_DEVICE_NOTIFY,
 966                                        acpi_thermal_notify);
 967
 968         flush_workqueue(acpi_thermal_pm_queue);
 969         acpi_thermal_unregister_thermal_zone(tz);
 970         kfree(tz->trip_table);
 971         acpi_thermal_free_thermal_zone(tz);
 972 }
 973
 974 #ifdef CONFIG_PM_SLEEP
 975 static int acpi_thermal_suspend(struct device *dev)
 976 {
 977         /* Make sure the previously queued thermal check work has been done */
 978         flush_workqueue(acpi_thermal_pm_queue);
 979         return 0;
 980 }
 981
 982 static int acpi_thermal_resume(struct device *dev)
 983 {
 984         struct acpi_thermal *tz;
 985         int i, j, power_state;
 986
 987         if (!dev)
 988                 return -EINVAL;
 989
 990         tz = acpi_driver_data(to_acpi_device(dev));
 991         if (!tz)
 992                 return -EINVAL;
 993
 994         for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
 995                 struct acpi_thermal_trip *acpi_trip = &tz->trips.active[i].trip;
 996
 997                 if (!acpi_thermal_trip_valid(acpi_trip))
 998                         break;
 999
1000                 for (j = 0; j < acpi_trip->devices.count; j++) {
1001                         acpi_bus_update_power(acpi_trip->devices.handles[j],
1002                                               &power_state);
1003                 }
1004         }
1005
1006         acpi_queue_thermal_check(tz);
1007
1008         return AE_OK;
1009 }
1010 #else
1011 #define acpi_thermal_suspend    NULL
1012 #define acpi_thermal_resume     NULL
1013 #endif
1014 static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, acpi_thermal_suspend, acpi_thermal_resume);
1015
1016 static const struct acpi_device_id  thermal_device_ids[] = {
1017         {ACPI_THERMAL_HID, 0},
1018         {"", 0},
1019 };
1020 MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
1021
1022 static struct acpi_driver acpi_thermal_driver = {
1023         .name = "thermal",
1024         .class = ACPI_THERMAL_CLASS,
1025         .ids = thermal_device_ids,
1026         .ops = {
1027                 .add = acpi_thermal_add,
1028                 .remove = acpi_thermal_remove,
1029                 },
1030         .drv.pm = &acpi_thermal_pm,
1031 };
1032
1033 static int thermal_act(const struct dmi_system_id *d)
1034 {
1035         if (act == 0) {
1036                 pr_notice("%s detected: disabling all active thermal trip points\n",
1037                           d->ident);
1038                 act = -1;
1039         }
1040         return 0;
1041 }
1042
1043 static int thermal_nocrt(const struct dmi_system_id *d)
1044 {
1045         pr_notice("%s detected: disabling all critical thermal trip point actions.\n",
1046                   d->ident);
1047         crt = -1;
1048         return 0;
1049 }
1050
1051 static int thermal_tzp(const struct dmi_system_id *d)
1052 {
1053         if (tzp == 0) {
1054                 pr_notice("%s detected: enabling thermal zone polling\n",
1055                           d->ident);
1056                 tzp = 300;      /* 300 dS = 30 Seconds */
1057         }
1058         return 0;
1059 }
1060
1061 static int thermal_psv(const struct dmi_system_id *d)
1062 {
1063         if (psv == 0) {
1064                 pr_notice("%s detected: disabling all passive thermal trip points\n",
1065                           d->ident);
1066                 psv = -1;
1067         }
1068         return 0;
1069 }
1070
1071 static const struct dmi_system_id thermal_dmi_table[] __initconst = {
1072         /*
1073          * Award BIOS on this AOpen makes thermal control almost worthless.
1074          * http://bugzilla.kernel.org/show_bug.cgi?id=8842
1075          */
1076         {
1077          .callback = thermal_act,
1078          .ident = "AOpen i915GMm-HFS",
1079          .matches = {
1080                 DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1081                 DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1082                 },
1083         },
1084         {
1085          .callback = thermal_psv,
1086          .ident = "AOpen i915GMm-HFS",
1087          .matches = {
1088                 DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1089                 DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1090                 },
1091         },
1092         {
1093          .callback = thermal_tzp,
1094          .ident = "AOpen i915GMm-HFS",
1095          .matches = {
1096                 DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1097                 DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1098                 },
1099         },
1100         {
1101          .callback = thermal_nocrt,
1102          .ident = "Gigabyte GA-7ZX",
1103          .matches = {
1104                 DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
1105                 DMI_MATCH(DMI_BOARD_NAME, "7ZX"),
1106                 },
1107         },
1108         {}
1109 };
1110
1111 static int __init acpi_thermal_init(void)
1112 {
1113         int result;
1114
1115         dmi_check_system(thermal_dmi_table);
1116
1117         if (off) {
1118                 pr_notice("thermal control disabled\n");
1119                 return -ENODEV;
1120         }
1121
1122         acpi_thermal_pm_queue = alloc_workqueue("acpi_thermal_pm",
1123                                                 WQ_HIGHPRI | WQ_MEM_RECLAIM, 0);
1124         if (!acpi_thermal_pm_queue)
1125                 return -ENODEV;
1126
1127         result = acpi_bus_register_driver(&acpi_thermal_driver);
1128         if (result < 0) {
1129                 destroy_workqueue(acpi_thermal_pm_queue);
1130                 return -ENODEV;
1131         }
1132
1133         return 0;
1134 }
1135
1136 static void __exit acpi_thermal_exit(void)
1137 {
1138         acpi_bus_unregister_driver(&acpi_thermal_driver);
1139         destroy_workqueue(acpi_thermal_pm_queue);
1140 }
1141
1142 module_init(acpi_thermal_init);
1143 module_exit(acpi_thermal_exit);
1144
1145 MODULE_AUTHOR("Paul Diefenbaugh");
1146 MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
1147 MODULE_LICENSE("GPL");