linux/drivers/thermal/thermal_core.c
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   1/*
   2 *  thermal.c - Generic Thermal Management Sysfs support.
   3 *
   4 *  Copyright (C) 2008 Intel Corp
   5 *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   6 *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
   7 *
   8 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9 *
  10 *  This program is free software; you can redistribute it and/or modify
  11 *  it under the terms of the GNU General Public License as published by
  12 *  the Free Software Foundation; version 2 of the License.
  13 *
  14 *  This program is distributed in the hope that it will be useful, but
  15 *  WITHOUT ANY WARRANTY; without even the implied warranty of
  16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17 *  General Public License for more details.
  18 *
  19 *  You should have received a copy of the GNU General Public License along
  20 *  with this program; if not, write to the Free Software Foundation, Inc.,
  21 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  22 *
  23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  24 */
  25
  26#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  27
  28#include <linux/module.h>
  29#include <linux/device.h>
  30#include <linux/err.h>
  31#include <linux/slab.h>
  32#include <linux/kdev_t.h>
  33#include <linux/idr.h>
  34#include <linux/thermal.h>
  35#include <linux/reboot.h>
  36#include <linux/string.h>
  37#include <net/netlink.h>
  38#include <net/genetlink.h>
  39
  40#include "thermal_core.h"
  41#include "thermal_hwmon.h"
  42
  43MODULE_AUTHOR("Zhang Rui");
  44MODULE_DESCRIPTION("Generic thermal management sysfs support");
  45MODULE_LICENSE("GPL v2");
  46
  47static DEFINE_IDR(thermal_tz_idr);
  48static DEFINE_IDR(thermal_cdev_idr);
  49static DEFINE_MUTEX(thermal_idr_lock);
  50
  51static LIST_HEAD(thermal_tz_list);
  52static LIST_HEAD(thermal_cdev_list);
  53static LIST_HEAD(thermal_governor_list);
  54
  55static DEFINE_MUTEX(thermal_list_lock);
  56static DEFINE_MUTEX(thermal_governor_lock);
  57
  58static struct thermal_governor *__find_governor(const char *name)
  59{
  60        struct thermal_governor *pos;
  61
  62        list_for_each_entry(pos, &thermal_governor_list, governor_list)
  63                if (!strnicmp(name, pos->name, THERMAL_NAME_LENGTH))
  64                        return pos;
  65
  66        return NULL;
  67}
  68
  69int thermal_register_governor(struct thermal_governor *governor)
  70{
  71        int err;
  72        const char *name;
  73        struct thermal_zone_device *pos;
  74
  75        if (!governor)
  76                return -EINVAL;
  77
  78        mutex_lock(&thermal_governor_lock);
  79
  80        err = -EBUSY;
  81        if (__find_governor(governor->name) == NULL) {
  82                err = 0;
  83                list_add(&governor->governor_list, &thermal_governor_list);
  84        }
  85
  86        mutex_lock(&thermal_list_lock);
  87
  88        list_for_each_entry(pos, &thermal_tz_list, node) {
  89                if (pos->governor)
  90                        continue;
  91                if (pos->tzp)
  92                        name = pos->tzp->governor_name;
  93                else
  94                        name = DEFAULT_THERMAL_GOVERNOR;
  95                if (!strnicmp(name, governor->name, THERMAL_NAME_LENGTH))
  96                        pos->governor = governor;
  97        }
  98
  99        mutex_unlock(&thermal_list_lock);
 100        mutex_unlock(&thermal_governor_lock);
 101
 102        return err;
 103}
 104
 105void thermal_unregister_governor(struct thermal_governor *governor)
 106{
 107        struct thermal_zone_device *pos;
 108
 109        if (!governor)
 110                return;
 111
 112        mutex_lock(&thermal_governor_lock);
 113
 114        if (__find_governor(governor->name) == NULL)
 115                goto exit;
 116
 117        mutex_lock(&thermal_list_lock);
 118
 119        list_for_each_entry(pos, &thermal_tz_list, node) {
 120                if (!strnicmp(pos->governor->name, governor->name,
 121                                                THERMAL_NAME_LENGTH))
 122                        pos->governor = NULL;
 123        }
 124
 125        mutex_unlock(&thermal_list_lock);
 126        list_del(&governor->governor_list);
 127exit:
 128        mutex_unlock(&thermal_governor_lock);
 129        return;
 130}
 131
 132static int get_idr(struct idr *idr, struct mutex *lock, int *id)
 133{
 134        int ret;
 135
 136        if (lock)
 137                mutex_lock(lock);
 138        ret = idr_alloc(idr, NULL, 0, 0, GFP_KERNEL);
 139        if (lock)
 140                mutex_unlock(lock);
 141        if (unlikely(ret < 0))
 142                return ret;
 143        *id = ret;
 144        return 0;
 145}
 146
 147static void release_idr(struct idr *idr, struct mutex *lock, int id)
 148{
 149        if (lock)
 150                mutex_lock(lock);
 151        idr_remove(idr, id);
 152        if (lock)
 153                mutex_unlock(lock);
 154}
 155
 156int get_tz_trend(struct thermal_zone_device *tz, int trip)
 157{
 158        enum thermal_trend trend;
 159
 160        if (tz->emul_temperature || !tz->ops->get_trend ||
 161            tz->ops->get_trend(tz, trip, &trend)) {
 162                if (tz->temperature > tz->last_temperature)
 163                        trend = THERMAL_TREND_RAISING;
 164                else if (tz->temperature < tz->last_temperature)
 165                        trend = THERMAL_TREND_DROPPING;
 166                else
 167                        trend = THERMAL_TREND_STABLE;
 168        }
 169
 170        return trend;
 171}
 172EXPORT_SYMBOL(get_tz_trend);
 173
 174struct thermal_instance *get_thermal_instance(struct thermal_zone_device *tz,
 175                        struct thermal_cooling_device *cdev, int trip)
 176{
 177        struct thermal_instance *pos = NULL;
 178        struct thermal_instance *target_instance = NULL;
 179
 180        mutex_lock(&tz->lock);
 181        mutex_lock(&cdev->lock);
 182
 183        list_for_each_entry(pos, &tz->thermal_instances, tz_node) {
 184                if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 185                        target_instance = pos;
 186                        break;
 187                }
 188        }
 189
 190        mutex_unlock(&cdev->lock);
 191        mutex_unlock(&tz->lock);
 192
 193        return target_instance;
 194}
 195EXPORT_SYMBOL(get_thermal_instance);
 196
 197static void print_bind_err_msg(struct thermal_zone_device *tz,
 198                        struct thermal_cooling_device *cdev, int ret)
 199{
 200        dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 201                                tz->type, cdev->type, ret);
 202}
 203
 204static void __bind(struct thermal_zone_device *tz, int mask,
 205                        struct thermal_cooling_device *cdev,
 206                        unsigned long *limits)
 207{
 208        int i, ret;
 209
 210        for (i = 0; i < tz->trips; i++) {
 211                if (mask & (1 << i)) {
 212                        unsigned long upper, lower;
 213
 214                        upper = THERMAL_NO_LIMIT;
 215                        lower = THERMAL_NO_LIMIT;
 216                        if (limits) {
 217                                lower = limits[i * 2];
 218                                upper = limits[i * 2 + 1];
 219                        }
 220                        ret = thermal_zone_bind_cooling_device(tz, i, cdev,
 221                                                               upper, lower);
 222                        if (ret)
 223                                print_bind_err_msg(tz, cdev, ret);
 224                }
 225        }
 226}
 227
 228static void __unbind(struct thermal_zone_device *tz, int mask,
 229                        struct thermal_cooling_device *cdev)
 230{
 231        int i;
 232
 233        for (i = 0; i < tz->trips; i++)
 234                if (mask & (1 << i))
 235                        thermal_zone_unbind_cooling_device(tz, i, cdev);
 236}
 237
 238static void bind_cdev(struct thermal_cooling_device *cdev)
 239{
 240        int i, ret;
 241        const struct thermal_zone_params *tzp;
 242        struct thermal_zone_device *pos = NULL;
 243
 244        mutex_lock(&thermal_list_lock);
 245
 246        list_for_each_entry(pos, &thermal_tz_list, node) {
 247                if (!pos->tzp && !pos->ops->bind)
 248                        continue;
 249
 250                if (!pos->tzp && pos->ops->bind) {
 251                        ret = pos->ops->bind(pos, cdev);
 252                        if (ret)
 253                                print_bind_err_msg(pos, cdev, ret);
 254                }
 255
 256                tzp = pos->tzp;
 257                if (!tzp || !tzp->tbp)
 258                        continue;
 259
 260                for (i = 0; i < tzp->num_tbps; i++) {
 261                        if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 262                                continue;
 263                        if (tzp->tbp[i].match(pos, cdev))
 264                                continue;
 265                        tzp->tbp[i].cdev = cdev;
 266                        __bind(pos, tzp->tbp[i].trip_mask, cdev,
 267                               tzp->tbp[i].binding_limits);
 268                }
 269        }
 270
 271        mutex_unlock(&thermal_list_lock);
 272}
 273
 274static void bind_tz(struct thermal_zone_device *tz)
 275{
 276        int i, ret;
 277        struct thermal_cooling_device *pos = NULL;
 278        const struct thermal_zone_params *tzp = tz->tzp;
 279
 280        if (!tzp && !tz->ops->bind)
 281                return;
 282
 283        mutex_lock(&thermal_list_lock);
 284
 285        /* If there is no platform data, try to use ops->bind */
 286        if (!tzp && tz->ops->bind) {
 287                list_for_each_entry(pos, &thermal_cdev_list, node) {
 288                        ret = tz->ops->bind(tz, pos);
 289                        if (ret)
 290                                print_bind_err_msg(tz, pos, ret);
 291                }
 292                goto exit;
 293        }
 294
 295        if (!tzp || !tzp->tbp)
 296                goto exit;
 297
 298        list_for_each_entry(pos, &thermal_cdev_list, node) {
 299                for (i = 0; i < tzp->num_tbps; i++) {
 300                        if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
 301                                continue;
 302                        if (tzp->tbp[i].match(tz, pos))
 303                                continue;
 304                        tzp->tbp[i].cdev = pos;
 305                        __bind(tz, tzp->tbp[i].trip_mask, pos,
 306                               tzp->tbp[i].binding_limits);
 307                }
 308        }
 309exit:
 310        mutex_unlock(&thermal_list_lock);
 311}
 312
 313static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 314                                            int delay)
 315{
 316        if (delay > 1000)
 317                mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 318                                 round_jiffies(msecs_to_jiffies(delay)));
 319        else if (delay)
 320                mod_delayed_work(system_freezable_wq, &tz->poll_queue,
 321                                 msecs_to_jiffies(delay));
 322        else
 323                cancel_delayed_work(&tz->poll_queue);
 324}
 325
 326static void monitor_thermal_zone(struct thermal_zone_device *tz)
 327{
 328        mutex_lock(&tz->lock);
 329
 330        if (tz->passive)
 331                thermal_zone_device_set_polling(tz, tz->passive_delay);
 332        else if (tz->polling_delay)
 333                thermal_zone_device_set_polling(tz, tz->polling_delay);
 334        else
 335                thermal_zone_device_set_polling(tz, 0);
 336
 337        mutex_unlock(&tz->lock);
 338}
 339
 340static void handle_non_critical_trips(struct thermal_zone_device *tz,
 341                        int trip, enum thermal_trip_type trip_type)
 342{
 343        if (tz->governor)
 344                tz->governor->throttle(tz, trip);
 345}
 346
 347static void handle_critical_trips(struct thermal_zone_device *tz,
 348                                int trip, enum thermal_trip_type trip_type)
 349{
 350        long trip_temp;
 351
 352        tz->ops->get_trip_temp(tz, trip, &trip_temp);
 353
 354        /* If we have not crossed the trip_temp, we do not care. */
 355        if (tz->temperature < trip_temp)
 356                return;
 357
 358        if (tz->ops->notify)
 359                tz->ops->notify(tz, trip, trip_type);
 360
 361        if (trip_type == THERMAL_TRIP_CRITICAL) {
 362                dev_emerg(&tz->device,
 363                          "critical temperature reached(%d C),shutting down\n",
 364                          tz->temperature / 1000);
 365                orderly_poweroff(true);
 366        }
 367}
 368
 369static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
 370{
 371        enum thermal_trip_type type;
 372
 373        tz->ops->get_trip_type(tz, trip, &type);
 374
 375        if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
 376                handle_critical_trips(tz, trip, type);
 377        else
 378                handle_non_critical_trips(tz, trip, type);
 379        /*
 380         * Alright, we handled this trip successfully.
 381         * So, start monitoring again.
 382         */
 383        monitor_thermal_zone(tz);
 384}
 385
 386/**
 387 * thermal_zone_get_temp() - returns its the temperature of thermal zone
 388 * @tz: a valid pointer to a struct thermal_zone_device
 389 * @temp: a valid pointer to where to store the resulting temperature.
 390 *
 391 * When a valid thermal zone reference is passed, it will fetch its
 392 * temperature and fill @temp.
 393 *
 394 * Return: On success returns 0, an error code otherwise
 395 */
 396int thermal_zone_get_temp(struct thermal_zone_device *tz, unsigned long *temp)
 397{
 398        int ret = -EINVAL;
 399#ifdef CONFIG_THERMAL_EMULATION
 400        int count;
 401        unsigned long crit_temp = -1UL;
 402        enum thermal_trip_type type;
 403#endif
 404
 405        if (!tz || IS_ERR(tz))
 406                goto exit;
 407
 408        mutex_lock(&tz->lock);
 409
 410        ret = tz->ops->get_temp(tz, temp);
 411#ifdef CONFIG_THERMAL_EMULATION
 412        if (!tz->emul_temperature)
 413                goto skip_emul;
 414
 415        for (count = 0; count < tz->trips; count++) {
 416                ret = tz->ops->get_trip_type(tz, count, &type);
 417                if (!ret && type == THERMAL_TRIP_CRITICAL) {
 418                        ret = tz->ops->get_trip_temp(tz, count, &crit_temp);
 419                        break;
 420                }
 421        }
 422
 423        if (ret)
 424                goto skip_emul;
 425
 426        if (*temp < crit_temp)
 427                *temp = tz->emul_temperature;
 428skip_emul:
 429#endif
 430        mutex_unlock(&tz->lock);
 431exit:
 432        return ret;
 433}
 434EXPORT_SYMBOL_GPL(thermal_zone_get_temp);
 435
 436static void update_temperature(struct thermal_zone_device *tz)
 437{
 438        long temp;
 439        int ret;
 440
 441        ret = thermal_zone_get_temp(tz, &temp);
 442        if (ret) {
 443                dev_warn(&tz->device, "failed to read out thermal zone %d\n",
 444                         tz->id);
 445                return;
 446        }
 447
 448        mutex_lock(&tz->lock);
 449        tz->last_temperature = tz->temperature;
 450        tz->temperature = temp;
 451        mutex_unlock(&tz->lock);
 452}
 453
 454void thermal_zone_device_update(struct thermal_zone_device *tz)
 455{
 456        int count;
 457
 458        update_temperature(tz);
 459
 460        for (count = 0; count < tz->trips; count++)
 461                handle_thermal_trip(tz, count);
 462}
 463EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 464
 465static void thermal_zone_device_check(struct work_struct *work)
 466{
 467        struct thermal_zone_device *tz = container_of(work, struct
 468                                                      thermal_zone_device,
 469                                                      poll_queue.work);
 470        thermal_zone_device_update(tz);
 471}
 472
 473/* sys I/F for thermal zone */
 474
 475#define to_thermal_zone(_dev) \
 476        container_of(_dev, struct thermal_zone_device, device)
 477
 478static ssize_t
 479type_show(struct device *dev, struct device_attribute *attr, char *buf)
 480{
 481        struct thermal_zone_device *tz = to_thermal_zone(dev);
 482
 483        return sprintf(buf, "%s\n", tz->type);
 484}
 485
 486static ssize_t
 487temp_show(struct device *dev, struct device_attribute *attr, char *buf)
 488{
 489        struct thermal_zone_device *tz = to_thermal_zone(dev);
 490        long temperature;
 491        int ret;
 492
 493        ret = thermal_zone_get_temp(tz, &temperature);
 494
 495        if (ret)
 496                return ret;
 497
 498        return sprintf(buf, "%ld\n", temperature);
 499}
 500
 501static ssize_t
 502mode_show(struct device *dev, struct device_attribute *attr, char *buf)
 503{
 504        struct thermal_zone_device *tz = to_thermal_zone(dev);
 505        enum thermal_device_mode mode;
 506        int result;
 507
 508        if (!tz->ops->get_mode)
 509                return -EPERM;
 510
 511        result = tz->ops->get_mode(tz, &mode);
 512        if (result)
 513                return result;
 514
 515        return sprintf(buf, "%s\n", mode == THERMAL_DEVICE_ENABLED ? "enabled"
 516                       : "disabled");
 517}
 518
 519static ssize_t
 520mode_store(struct device *dev, struct device_attribute *attr,
 521           const char *buf, size_t count)
 522{
 523        struct thermal_zone_device *tz = to_thermal_zone(dev);
 524        int result;
 525
 526        if (!tz->ops->set_mode)
 527                return -EPERM;
 528
 529        if (!strncmp(buf, "enabled", sizeof("enabled") - 1))
 530                result = tz->ops->set_mode(tz, THERMAL_DEVICE_ENABLED);
 531        else if (!strncmp(buf, "disabled", sizeof("disabled") - 1))
 532                result = tz->ops->set_mode(tz, THERMAL_DEVICE_DISABLED);
 533        else
 534                result = -EINVAL;
 535
 536        if (result)
 537                return result;
 538
 539        return count;
 540}
 541
 542static ssize_t
 543trip_point_type_show(struct device *dev, struct device_attribute *attr,
 544                     char *buf)
 545{
 546        struct thermal_zone_device *tz = to_thermal_zone(dev);
 547        enum thermal_trip_type type;
 548        int trip, result;
 549
 550        if (!tz->ops->get_trip_type)
 551                return -EPERM;
 552
 553        if (!sscanf(attr->attr.name, "trip_point_%d_type", &trip))
 554                return -EINVAL;
 555
 556        result = tz->ops->get_trip_type(tz, trip, &type);
 557        if (result)
 558                return result;
 559
 560        switch (type) {
 561        case THERMAL_TRIP_CRITICAL:
 562                return sprintf(buf, "critical\n");
 563        case THERMAL_TRIP_HOT:
 564                return sprintf(buf, "hot\n");
 565        case THERMAL_TRIP_PASSIVE:
 566                return sprintf(buf, "passive\n");
 567        case THERMAL_TRIP_ACTIVE:
 568                return sprintf(buf, "active\n");
 569        default:
 570                return sprintf(buf, "unknown\n");
 571        }
 572}
 573
 574static ssize_t
 575trip_point_temp_store(struct device *dev, struct device_attribute *attr,
 576                     const char *buf, size_t count)
 577{
 578        struct thermal_zone_device *tz = to_thermal_zone(dev);
 579        int trip, ret;
 580        unsigned long temperature;
 581
 582        if (!tz->ops->set_trip_temp)
 583                return -EPERM;
 584
 585        if (!sscanf(attr->attr.name, "trip_point_%d_temp", &trip))
 586                return -EINVAL;
 587
 588        if (kstrtoul(buf, 10, &temperature))
 589                return -EINVAL;
 590
 591        ret = tz->ops->set_trip_temp(tz, trip, temperature);
 592
 593        return ret ? ret : count;
 594}
 595
 596static ssize_t
 597trip_point_temp_show(struct device *dev, struct device_attribute *attr,
 598                     char *buf)
 599{
 600        struct thermal_zone_device *tz = to_thermal_zone(dev);
 601        int trip, ret;
 602        long temperature;
 603
 604        if (!tz->ops->get_trip_temp)
 605                return -EPERM;
 606
 607        if (!sscanf(attr->attr.name, "trip_point_%d_temp", &trip))
 608                return -EINVAL;
 609
 610        ret = tz->ops->get_trip_temp(tz, trip, &temperature);
 611
 612        if (ret)
 613                return ret;
 614
 615        return sprintf(buf, "%ld\n", temperature);
 616}
 617
 618static ssize_t
 619trip_point_hyst_store(struct device *dev, struct device_attribute *attr,
 620                        const char *buf, size_t count)
 621{
 622        struct thermal_zone_device *tz = to_thermal_zone(dev);
 623        int trip, ret;
 624        unsigned long temperature;
 625
 626        if (!tz->ops->set_trip_hyst)
 627                return -EPERM;
 628
 629        if (!sscanf(attr->attr.name, "trip_point_%d_hyst", &trip))
 630                return -EINVAL;
 631
 632        if (kstrtoul(buf, 10, &temperature))
 633                return -EINVAL;
 634
 635        /*
 636         * We are not doing any check on the 'temperature' value
 637         * here. The driver implementing 'set_trip_hyst' has to
 638         * take care of this.
 639         */
 640        ret = tz->ops->set_trip_hyst(tz, trip, temperature);
 641
 642        return ret ? ret : count;
 643}
 644
 645static ssize_t
 646trip_point_hyst_show(struct device *dev, struct device_attribute *attr,
 647                        char *buf)
 648{
 649        struct thermal_zone_device *tz = to_thermal_zone(dev);
 650        int trip, ret;
 651        unsigned long temperature;
 652
 653        if (!tz->ops->get_trip_hyst)
 654                return -EPERM;
 655
 656        if (!sscanf(attr->attr.name, "trip_point_%d_hyst", &trip))
 657                return -EINVAL;
 658
 659        ret = tz->ops->get_trip_hyst(tz, trip, &temperature);
 660
 661        return ret ? ret : sprintf(buf, "%ld\n", temperature);
 662}
 663
 664static ssize_t
 665passive_store(struct device *dev, struct device_attribute *attr,
 666                    const char *buf, size_t count)
 667{
 668        struct thermal_zone_device *tz = to_thermal_zone(dev);
 669        struct thermal_cooling_device *cdev = NULL;
 670        int state;
 671
 672        if (!sscanf(buf, "%d\n", &state))
 673                return -EINVAL;
 674
 675        /* sanity check: values below 1000 millicelcius don't make sense
 676         * and can cause the system to go into a thermal heart attack
 677         */
 678        if (state && state < 1000)
 679                return -EINVAL;
 680
 681        if (state && !tz->forced_passive) {
 682                mutex_lock(&thermal_list_lock);
 683                list_for_each_entry(cdev, &thermal_cdev_list, node) {
 684                        if (!strncmp("Processor", cdev->type,
 685                                     sizeof("Processor")))
 686                                thermal_zone_bind_cooling_device(tz,
 687                                                THERMAL_TRIPS_NONE, cdev,
 688                                                THERMAL_NO_LIMIT,
 689                                                THERMAL_NO_LIMIT);
 690                }
 691                mutex_unlock(&thermal_list_lock);
 692                if (!tz->passive_delay)
 693                        tz->passive_delay = 1000;
 694        } else if (!state && tz->forced_passive) {
 695                mutex_lock(&thermal_list_lock);
 696                list_for_each_entry(cdev, &thermal_cdev_list, node) {
 697                        if (!strncmp("Processor", cdev->type,
 698                                     sizeof("Processor")))
 699                                thermal_zone_unbind_cooling_device(tz,
 700                                                                   THERMAL_TRIPS_NONE,
 701                                                                   cdev);
 702                }
 703                mutex_unlock(&thermal_list_lock);
 704                tz->passive_delay = 0;
 705        }
 706
 707        tz->forced_passive = state;
 708
 709        thermal_zone_device_update(tz);
 710
 711        return count;
 712}
 713
 714static ssize_t
 715passive_show(struct device *dev, struct device_attribute *attr,
 716                   char *buf)
 717{
 718        struct thermal_zone_device *tz = to_thermal_zone(dev);
 719
 720        return sprintf(buf, "%d\n", tz->forced_passive);
 721}
 722
 723static ssize_t
 724policy_store(struct device *dev, struct device_attribute *attr,
 725                    const char *buf, size_t count)
 726{
 727        int ret = -EINVAL;
 728        struct thermal_zone_device *tz = to_thermal_zone(dev);
 729        struct thermal_governor *gov;
 730        char name[THERMAL_NAME_LENGTH];
 731
 732        snprintf(name, sizeof(name), "%s", buf);
 733
 734        mutex_lock(&thermal_governor_lock);
 735
 736        gov = __find_governor(strim(name));
 737        if (!gov)
 738                goto exit;
 739
 740        tz->governor = gov;
 741        ret = count;
 742
 743exit:
 744        mutex_unlock(&thermal_governor_lock);
 745        return ret;
 746}
 747
 748static ssize_t
 749policy_show(struct device *dev, struct device_attribute *devattr, char *buf)
 750{
 751        struct thermal_zone_device *tz = to_thermal_zone(dev);
 752
 753        return sprintf(buf, "%s\n", tz->governor->name);
 754}
 755
 756#ifdef CONFIG_THERMAL_EMULATION
 757static ssize_t
 758emul_temp_store(struct device *dev, struct device_attribute *attr,
 759                     const char *buf, size_t count)
 760{
 761        struct thermal_zone_device *tz = to_thermal_zone(dev);
 762        int ret = 0;
 763        unsigned long temperature;
 764
 765        if (kstrtoul(buf, 10, &temperature))
 766                return -EINVAL;
 767
 768        if (!tz->ops->set_emul_temp) {
 769                mutex_lock(&tz->lock);
 770                tz->emul_temperature = temperature;
 771                mutex_unlock(&tz->lock);
 772        } else {
 773                ret = tz->ops->set_emul_temp(tz, temperature);
 774        }
 775
 776        return ret ? ret : count;
 777}
 778static DEVICE_ATTR(emul_temp, S_IWUSR, NULL, emul_temp_store);
 779#endif/*CONFIG_THERMAL_EMULATION*/
 780
 781static DEVICE_ATTR(type, 0444, type_show, NULL);
 782static DEVICE_ATTR(temp, 0444, temp_show, NULL);
 783static DEVICE_ATTR(mode, 0644, mode_show, mode_store);
 784static DEVICE_ATTR(passive, S_IRUGO | S_IWUSR, passive_show, passive_store);
 785static DEVICE_ATTR(policy, S_IRUGO | S_IWUSR, policy_show, policy_store);
 786
 787/* sys I/F for cooling device */
 788#define to_cooling_device(_dev) \
 789        container_of(_dev, struct thermal_cooling_device, device)
 790
 791static ssize_t
 792thermal_cooling_device_type_show(struct device *dev,
 793                                 struct device_attribute *attr, char *buf)
 794{
 795        struct thermal_cooling_device *cdev = to_cooling_device(dev);
 796
 797        return sprintf(buf, "%s\n", cdev->type);
 798}
 799
 800static ssize_t
 801thermal_cooling_device_max_state_show(struct device *dev,
 802                                      struct device_attribute *attr, char *buf)
 803{
 804        struct thermal_cooling_device *cdev = to_cooling_device(dev);
 805        unsigned long state;
 806        int ret;
 807
 808        ret = cdev->ops->get_max_state(cdev, &state);
 809        if (ret)
 810                return ret;
 811        return sprintf(buf, "%ld\n", state);
 812}
 813
 814static ssize_t
 815thermal_cooling_device_cur_state_show(struct device *dev,
 816                                      struct device_attribute *attr, char *buf)
 817{
 818        struct thermal_cooling_device *cdev = to_cooling_device(dev);
 819        unsigned long state;
 820        int ret;
 821
 822        ret = cdev->ops->get_cur_state(cdev, &state);
 823        if (ret)
 824                return ret;
 825        return sprintf(buf, "%ld\n", state);
 826}
 827
 828static ssize_t
 829thermal_cooling_device_cur_state_store(struct device *dev,
 830                                       struct device_attribute *attr,
 831                                       const char *buf, size_t count)
 832{
 833        struct thermal_cooling_device *cdev = to_cooling_device(dev);
 834        unsigned long state;
 835        int result;
 836
 837        if (!sscanf(buf, "%ld\n", &state))
 838                return -EINVAL;
 839
 840        if ((long)state < 0)
 841                return -EINVAL;
 842
 843        result = cdev->ops->set_cur_state(cdev, state);
 844        if (result)
 845                return result;
 846        return count;
 847}
 848
 849static struct device_attribute dev_attr_cdev_type =
 850__ATTR(type, 0444, thermal_cooling_device_type_show, NULL);
 851static DEVICE_ATTR(max_state, 0444,
 852                   thermal_cooling_device_max_state_show, NULL);
 853static DEVICE_ATTR(cur_state, 0644,
 854                   thermal_cooling_device_cur_state_show,
 855                   thermal_cooling_device_cur_state_store);
 856
 857static ssize_t
 858thermal_cooling_device_trip_point_show(struct device *dev,
 859                                       struct device_attribute *attr, char *buf)
 860{
 861        struct thermal_instance *instance;
 862
 863        instance =
 864            container_of(attr, struct thermal_instance, attr);
 865
 866        if (instance->trip == THERMAL_TRIPS_NONE)
 867                return sprintf(buf, "-1\n");
 868        else
 869                return sprintf(buf, "%d\n", instance->trip);
 870}
 871
 872/* Device management */
 873
 874/**
 875 * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
 876 * @tz:         pointer to struct thermal_zone_device
 877 * @trip:       indicates which trip point the cooling devices is
 878 *              associated with in this thermal zone.
 879 * @cdev:       pointer to struct thermal_cooling_device
 880 * @upper:      the Maximum cooling state for this trip point.
 881 *              THERMAL_NO_LIMIT means no upper limit,
 882 *              and the cooling device can be in max_state.
 883 * @lower:      the Minimum cooling state can be used for this trip point.
 884 *              THERMAL_NO_LIMIT means no lower limit,
 885 *              and the cooling device can be in cooling state 0.
 886 *
 887 * This interface function bind a thermal cooling device to the certain trip
 888 * point of a thermal zone device.
 889 * This function is usually called in the thermal zone device .bind callback.
 890 *
 891 * Return: 0 on success, the proper error value otherwise.
 892 */
 893int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 894                                     int trip,
 895                                     struct thermal_cooling_device *cdev,
 896                                     unsigned long upper, unsigned long lower)
 897{
 898        struct thermal_instance *dev;
 899        struct thermal_instance *pos;
 900        struct thermal_zone_device *pos1;
 901        struct thermal_cooling_device *pos2;
 902        unsigned long max_state;
 903        int result;
 904
 905        if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
 906                return -EINVAL;
 907
 908        list_for_each_entry(pos1, &thermal_tz_list, node) {
 909                if (pos1 == tz)
 910                        break;
 911        }
 912        list_for_each_entry(pos2, &thermal_cdev_list, node) {
 913                if (pos2 == cdev)
 914                        break;
 915        }
 916
 917        if (tz != pos1 || cdev != pos2)
 918                return -EINVAL;
 919
 920        cdev->ops->get_max_state(cdev, &max_state);
 921
 922        /* lower default 0, upper default max_state */
 923        lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 924        upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
 925
 926        if (lower > upper || upper > max_state)
 927                return -EINVAL;
 928
 929        dev =
 930            kzalloc(sizeof(struct thermal_instance), GFP_KERNEL);
 931        if (!dev)
 932                return -ENOMEM;
 933        dev->tz = tz;
 934        dev->cdev = cdev;
 935        dev->trip = trip;
 936        dev->upper = upper;
 937        dev->lower = lower;
 938        dev->target = THERMAL_NO_TARGET;
 939
 940        result = get_idr(&tz->idr, &tz->lock, &dev->id);
 941        if (result)
 942                goto free_mem;
 943
 944        sprintf(dev->name, "cdev%d", dev->id);
 945        result =
 946            sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 947        if (result)
 948                goto release_idr;
 949
 950        sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
 951        sysfs_attr_init(&dev->attr.attr);
 952        dev->attr.attr.name = dev->attr_name;
 953        dev->attr.attr.mode = 0444;
 954        dev->attr.show = thermal_cooling_device_trip_point_show;
 955        result = device_create_file(&tz->device, &dev->attr);
 956        if (result)
 957                goto remove_symbol_link;
 958
 959        mutex_lock(&tz->lock);
 960        mutex_lock(&cdev->lock);
 961        list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 962            if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 963                result = -EEXIST;
 964                break;
 965        }
 966        if (!result) {
 967                list_add_tail(&dev->tz_node, &tz->thermal_instances);
 968                list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 969        }
 970        mutex_unlock(&cdev->lock);
 971        mutex_unlock(&tz->lock);
 972
 973        if (!result)
 974                return 0;
 975
 976        device_remove_file(&tz->device, &dev->attr);
 977remove_symbol_link:
 978        sysfs_remove_link(&tz->device.kobj, dev->name);
 979release_idr:
 980        release_idr(&tz->idr, &tz->lock, dev->id);
 981free_mem:
 982        kfree(dev);
 983        return result;
 984}
 985EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 986
 987/**
 988 * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
 989 *                                        thermal zone.
 990 * @tz:         pointer to a struct thermal_zone_device.
 991 * @trip:       indicates which trip point the cooling devices is
 992 *              associated with in this thermal zone.
 993 * @cdev:       pointer to a struct thermal_cooling_device.
 994 *
 995 * This interface function unbind a thermal cooling device from the certain
 996 * trip point of a thermal zone device.
 997 * This function is usually called in the thermal zone device .unbind callback.
 998 *
 999 * Return: 0 on success, the proper error value otherwise.
1000 */
1001int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
1002                                       int trip,
1003                                       struct thermal_cooling_device *cdev)
1004{
1005        struct thermal_instance *pos, *next;
1006
1007        mutex_lock(&tz->lock);
1008        mutex_lock(&cdev->lock);
1009        list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
1010                if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
1011                        list_del(&pos->tz_node);
1012                        list_del(&pos->cdev_node);
1013                        mutex_unlock(&cdev->lock);
1014                        mutex_unlock(&tz->lock);
1015                        goto unbind;
1016                }
1017        }
1018        mutex_unlock(&cdev->lock);
1019        mutex_unlock(&tz->lock);
1020
1021        return -ENODEV;
1022
1023unbind:
1024        device_remove_file(&tz->device, &pos->attr);
1025        sysfs_remove_link(&tz->device.kobj, pos->name);
1026        release_idr(&tz->idr, &tz->lock, pos->id);
1027        kfree(pos);
1028        return 0;
1029}
1030EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
1031
1032static void thermal_release(struct device *dev)
1033{
1034        struct thermal_zone_device *tz;
1035        struct thermal_cooling_device *cdev;
1036
1037        if (!strncmp(dev_name(dev), "thermal_zone",
1038                     sizeof("thermal_zone") - 1)) {
1039                tz = to_thermal_zone(dev);
1040                kfree(tz);
1041        } else {
1042                cdev = to_cooling_device(dev);
1043                kfree(cdev);
1044        }
1045}
1046
1047static struct class thermal_class = {
1048        .name = "thermal",
1049        .dev_release = thermal_release,
1050};
1051
1052/**
1053 * thermal_cooling_device_register() - register a new thermal cooling device
1054 * @type:       the thermal cooling device type.
1055 * @devdata:    device private data.
1056 * @ops:                standard thermal cooling devices callbacks.
1057 *
1058 * This interface function adds a new thermal cooling device (fan/processor/...)
1059 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1060 * to all the thermal zone devices registered at the same time.
1061 *
1062 * Return: a pointer to the created struct thermal_cooling_device or an
1063 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1064 */
1065struct thermal_cooling_device *
1066thermal_cooling_device_register(char *type, void *devdata,
1067                                const struct thermal_cooling_device_ops *ops)
1068{
1069        struct thermal_cooling_device *cdev;
1070        int result;
1071
1072        if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1073                return ERR_PTR(-EINVAL);
1074
1075        if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1076            !ops->set_cur_state)
1077                return ERR_PTR(-EINVAL);
1078
1079        cdev = kzalloc(sizeof(struct thermal_cooling_device), GFP_KERNEL);
1080        if (!cdev)
1081                return ERR_PTR(-ENOMEM);
1082
1083        result = get_idr(&thermal_cdev_idr, &thermal_idr_lock, &cdev->id);
1084        if (result) {
1085                kfree(cdev);
1086                return ERR_PTR(result);
1087        }
1088
1089        strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
1090        mutex_init(&cdev->lock);
1091        INIT_LIST_HEAD(&cdev->thermal_instances);
1092        cdev->ops = ops;
1093        cdev->updated = true;
1094        cdev->device.class = &thermal_class;
1095        cdev->devdata = devdata;
1096        dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1097        result = device_register(&cdev->device);
1098        if (result) {
1099                release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
1100                kfree(cdev);
1101                return ERR_PTR(result);
1102        }
1103
1104        /* sys I/F */
1105        if (type) {
1106                result = device_create_file(&cdev->device, &dev_attr_cdev_type);
1107                if (result)
1108                        goto unregister;
1109        }
1110
1111        result = device_create_file(&cdev->device, &dev_attr_max_state);
1112        if (result)
1113                goto unregister;
1114
1115        result = device_create_file(&cdev->device, &dev_attr_cur_state);
1116        if (result)
1117                goto unregister;
1118
1119        /* Add 'this' new cdev to the global cdev list */
1120        mutex_lock(&thermal_list_lock);
1121        list_add(&cdev->node, &thermal_cdev_list);
1122        mutex_unlock(&thermal_list_lock);
1123
1124        /* Update binding information for 'this' new cdev */
1125        bind_cdev(cdev);
1126
1127        return cdev;
1128
1129unregister:
1130        release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
1131        device_unregister(&cdev->device);
1132        return ERR_PTR(result);
1133}
1134EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1135
1136/**
1137 * thermal_cooling_device_unregister - removes the registered thermal cooling device
1138 * @cdev:       the thermal cooling device to remove.
1139 *
1140 * thermal_cooling_device_unregister() must be called when the device is no
1141 * longer needed.
1142 */
1143void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1144{
1145        int i;
1146        const struct thermal_zone_params *tzp;
1147        struct thermal_zone_device *tz;
1148        struct thermal_cooling_device *pos = NULL;
1149
1150        if (!cdev)
1151                return;
1152
1153        mutex_lock(&thermal_list_lock);
1154        list_for_each_entry(pos, &thermal_cdev_list, node)
1155            if (pos == cdev)
1156                break;
1157        if (pos != cdev) {
1158                /* thermal cooling device not found */
1159                mutex_unlock(&thermal_list_lock);
1160                return;
1161        }
1162        list_del(&cdev->node);
1163
1164        /* Unbind all thermal zones associated with 'this' cdev */
1165        list_for_each_entry(tz, &thermal_tz_list, node) {
1166                if (tz->ops->unbind) {
1167                        tz->ops->unbind(tz, cdev);
1168                        continue;
1169                }
1170
1171                if (!tz->tzp || !tz->tzp->tbp)
1172                        continue;
1173
1174                tzp = tz->tzp;
1175                for (i = 0; i < tzp->num_tbps; i++) {
1176                        if (tzp->tbp[i].cdev == cdev) {
1177                                __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1178                                tzp->tbp[i].cdev = NULL;
1179                        }
1180                }
1181        }
1182
1183        mutex_unlock(&thermal_list_lock);
1184
1185        if (cdev->type[0])
1186                device_remove_file(&cdev->device, &dev_attr_cdev_type);
1187        device_remove_file(&cdev->device, &dev_attr_max_state);
1188        device_remove_file(&cdev->device, &dev_attr_cur_state);
1189
1190        release_idr(&thermal_cdev_idr, &thermal_idr_lock, cdev->id);
1191        device_unregister(&cdev->device);
1192        return;
1193}
1194EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1195
1196void thermal_cdev_update(struct thermal_cooling_device *cdev)
1197{
1198        struct thermal_instance *instance;
1199        unsigned long target = 0;
1200
1201        /* cooling device is updated*/
1202        if (cdev->updated)
1203                return;
1204
1205        mutex_lock(&cdev->lock);
1206        /* Make sure cdev enters the deepest cooling state */
1207        list_for_each_entry(instance, &cdev->thermal_instances, cdev_node) {
1208                if (instance->target == THERMAL_NO_TARGET)
1209                        continue;
1210                if (instance->target > target)
1211                        target = instance->target;
1212        }
1213        mutex_unlock(&cdev->lock);
1214        cdev->ops->set_cur_state(cdev, target);
1215        cdev->updated = true;
1216}
1217EXPORT_SYMBOL(thermal_cdev_update);
1218
1219/**
1220 * thermal_notify_framework - Sensor drivers use this API to notify framework
1221 * @tz:         thermal zone device
1222 * @trip:       indicates which trip point has been crossed
1223 *
1224 * This function handles the trip events from sensor drivers. It starts
1225 * throttling the cooling devices according to the policy configured.
1226 * For CRITICAL and HOT trip points, this notifies the respective drivers,
1227 * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
1228 * The throttling policy is based on the configured platform data; if no
1229 * platform data is provided, this uses the step_wise throttling policy.
1230 */
1231void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
1232{
1233        handle_thermal_trip(tz, trip);
1234}
1235EXPORT_SYMBOL_GPL(thermal_notify_framework);
1236
1237/**
1238 * create_trip_attrs() - create attributes for trip points
1239 * @tz:         the thermal zone device
1240 * @mask:       Writeable trip point bitmap.
1241 *
1242 * helper function to instantiate sysfs entries for every trip
1243 * point and its properties of a struct thermal_zone_device.
1244 *
1245 * Return: 0 on success, the proper error value otherwise.
1246 */
1247static int create_trip_attrs(struct thermal_zone_device *tz, int mask)
1248{
1249        int indx;
1250        int size = sizeof(struct thermal_attr) * tz->trips;
1251
1252        tz->trip_type_attrs = kzalloc(size, GFP_KERNEL);
1253        if (!tz->trip_type_attrs)
1254                return -ENOMEM;
1255
1256        tz->trip_temp_attrs = kzalloc(size, GFP_KERNEL);
1257        if (!tz->trip_temp_attrs) {
1258                kfree(tz->trip_type_attrs);
1259                return -ENOMEM;
1260        }
1261
1262        if (tz->ops->get_trip_hyst) {
1263                tz->trip_hyst_attrs = kzalloc(size, GFP_KERNEL);
1264                if (!tz->trip_hyst_attrs) {
1265                        kfree(tz->trip_type_attrs);
1266                        kfree(tz->trip_temp_attrs);
1267                        return -ENOMEM;
1268                }
1269        }
1270
1271
1272        for (indx = 0; indx < tz->trips; indx++) {
1273                /* create trip type attribute */
1274                snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH,
1275                         "trip_point_%d_type", indx);
1276
1277                sysfs_attr_init(&tz->trip_type_attrs[indx].attr.attr);
1278                tz->trip_type_attrs[indx].attr.attr.name =
1279                                                tz->trip_type_attrs[indx].name;
1280                tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;
1281                tz->trip_type_attrs[indx].attr.show = trip_point_type_show;
1282
1283                device_create_file(&tz->device,
1284                                   &tz->trip_type_attrs[indx].attr);
1285
1286                /* create trip temp attribute */
1287                snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH,
1288                         "trip_point_%d_temp", indx);
1289
1290                sysfs_attr_init(&tz->trip_temp_attrs[indx].attr.attr);
1291                tz->trip_temp_attrs[indx].attr.attr.name =
1292                                                tz->trip_temp_attrs[indx].name;
1293                tz->trip_temp_attrs[indx].attr.attr.mode = S_IRUGO;
1294                tz->trip_temp_attrs[indx].attr.show = trip_point_temp_show;
1295                if (mask & (1 << indx)) {
1296                        tz->trip_temp_attrs[indx].attr.attr.mode |= S_IWUSR;
1297                        tz->trip_temp_attrs[indx].attr.store =
1298                                                        trip_point_temp_store;
1299                }
1300
1301                device_create_file(&tz->device,
1302                                   &tz->trip_temp_attrs[indx].attr);
1303
1304                /* create Optional trip hyst attribute */
1305                if (!tz->ops->get_trip_hyst)
1306                        continue;
1307                snprintf(tz->trip_hyst_attrs[indx].name, THERMAL_NAME_LENGTH,
1308                         "trip_point_%d_hyst", indx);
1309
1310                sysfs_attr_init(&tz->trip_hyst_attrs[indx].attr.attr);
1311                tz->trip_hyst_attrs[indx].attr.attr.name =
1312                                        tz->trip_hyst_attrs[indx].name;
1313                tz->trip_hyst_attrs[indx].attr.attr.mode = S_IRUGO;
1314                tz->trip_hyst_attrs[indx].attr.show = trip_point_hyst_show;
1315                if (tz->ops->set_trip_hyst) {
1316                        tz->trip_hyst_attrs[indx].attr.attr.mode |= S_IWUSR;
1317                        tz->trip_hyst_attrs[indx].attr.store =
1318                                        trip_point_hyst_store;
1319                }
1320
1321                device_create_file(&tz->device,
1322                                   &tz->trip_hyst_attrs[indx].attr);
1323        }
1324        return 0;
1325}
1326
1327static void remove_trip_attrs(struct thermal_zone_device *tz)
1328{
1329        int indx;
1330
1331        for (indx = 0; indx < tz->trips; indx++) {
1332                device_remove_file(&tz->device,
1333                                   &tz->trip_type_attrs[indx].attr);
1334                device_remove_file(&tz->device,
1335                                   &tz->trip_temp_attrs[indx].attr);
1336                if (tz->ops->get_trip_hyst)
1337                        device_remove_file(&tz->device,
1338                                  &tz->trip_hyst_attrs[indx].attr);
1339        }
1340        kfree(tz->trip_type_attrs);
1341        kfree(tz->trip_temp_attrs);
1342        kfree(tz->trip_hyst_attrs);
1343}
1344
1345/**
1346 * thermal_zone_device_register() - register a new thermal zone device
1347 * @type:       the thermal zone device type
1348 * @trips:      the number of trip points the thermal zone support
1349 * @mask:       a bit string indicating the writeablility of trip points
1350 * @devdata:    private device data
1351 * @ops:        standard thermal zone device callbacks
1352 * @tzp:        thermal zone platform parameters
1353 * @passive_delay: number of milliseconds to wait between polls when
1354 *                 performing passive cooling
1355 * @polling_delay: number of milliseconds to wait between polls when checking
1356 *                 whether trip points have been crossed (0 for interrupt
1357 *                 driven systems)
1358 *
1359 * This interface function adds a new thermal zone device (sensor) to
1360 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1361 * thermal cooling devices registered at the same time.
1362 * thermal_zone_device_unregister() must be called when the device is no
1363 * longer needed. The passive cooling depends on the .get_trend() return value.
1364 *
1365 * Return: a pointer to the created struct thermal_zone_device or an
1366 * in case of error, an ERR_PTR. Caller must check return value with
1367 * IS_ERR*() helpers.
1368 */
1369struct thermal_zone_device *thermal_zone_device_register(const char *type,
1370        int trips, int mask, void *devdata,
1371        const struct thermal_zone_device_ops *ops,
1372        const struct thermal_zone_params *tzp,
1373        int passive_delay, int polling_delay)
1374{
1375        struct thermal_zone_device *tz;
1376        enum thermal_trip_type trip_type;
1377        int result;
1378        int count;
1379        int passive = 0;
1380
1381        if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1382                return ERR_PTR(-EINVAL);
1383
1384        if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
1385                return ERR_PTR(-EINVAL);
1386
1387        if (!ops || !ops->get_temp)
1388                return ERR_PTR(-EINVAL);
1389
1390        if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1391                return ERR_PTR(-EINVAL);
1392
1393        tz = kzalloc(sizeof(struct thermal_zone_device), GFP_KERNEL);
1394        if (!tz)
1395                return ERR_PTR(-ENOMEM);
1396
1397        INIT_LIST_HEAD(&tz->thermal_instances);
1398        idr_init(&tz->idr);
1399        mutex_init(&tz->lock);
1400        result = get_idr(&thermal_tz_idr, &thermal_idr_lock, &tz->id);
1401        if (result) {
1402                kfree(tz);
1403                return ERR_PTR(result);
1404        }
1405
1406        strlcpy(tz->type, type ? : "", sizeof(tz->type));
1407        tz->ops = ops;
1408        tz->tzp = tzp;
1409        tz->device.class = &thermal_class;
1410        tz->devdata = devdata;
1411        tz->trips = trips;
1412        tz->passive_delay = passive_delay;
1413        tz->polling_delay = polling_delay;
1414
1415        dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1416        result = device_register(&tz->device);
1417        if (result) {
1418                release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1419                kfree(tz);
1420                return ERR_PTR(result);
1421        }
1422
1423        /* sys I/F */
1424        if (type) {
1425                result = device_create_file(&tz->device, &dev_attr_type);
1426                if (result)
1427                        goto unregister;
1428        }
1429
1430        result = device_create_file(&tz->device, &dev_attr_temp);
1431        if (result)
1432                goto unregister;
1433
1434        if (ops->get_mode) {
1435                result = device_create_file(&tz->device, &dev_attr_mode);
1436                if (result)
1437                        goto unregister;
1438        }
1439
1440        result = create_trip_attrs(tz, mask);
1441        if (result)
1442                goto unregister;
1443
1444        for (count = 0; count < trips; count++) {
1445                tz->ops->get_trip_type(tz, count, &trip_type);
1446                if (trip_type == THERMAL_TRIP_PASSIVE)
1447                        passive = 1;
1448        }
1449
1450        if (!passive) {
1451                result = device_create_file(&tz->device, &dev_attr_passive);
1452                if (result)
1453                        goto unregister;
1454        }
1455
1456#ifdef CONFIG_THERMAL_EMULATION
1457        result = device_create_file(&tz->device, &dev_attr_emul_temp);
1458        if (result)
1459                goto unregister;
1460#endif
1461        /* Create policy attribute */
1462        result = device_create_file(&tz->device, &dev_attr_policy);
1463        if (result)
1464                goto unregister;
1465
1466        /* Update 'this' zone's governor information */
1467        mutex_lock(&thermal_governor_lock);
1468
1469        if (tz->tzp)
1470                tz->governor = __find_governor(tz->tzp->governor_name);
1471        else
1472                tz->governor = __find_governor(DEFAULT_THERMAL_GOVERNOR);
1473
1474        mutex_unlock(&thermal_governor_lock);
1475
1476        if (!tz->tzp || !tz->tzp->no_hwmon) {
1477                result = thermal_add_hwmon_sysfs(tz);
1478                if (result)
1479                        goto unregister;
1480        }
1481
1482        mutex_lock(&thermal_list_lock);
1483        list_add_tail(&tz->node, &thermal_tz_list);
1484        mutex_unlock(&thermal_list_lock);
1485
1486        /* Bind cooling devices for this zone */
1487        bind_tz(tz);
1488
1489        INIT_DELAYED_WORK(&(tz->poll_queue), thermal_zone_device_check);
1490
1491        thermal_zone_device_update(tz);
1492
1493        if (!result)
1494                return tz;
1495
1496unregister:
1497        release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1498        device_unregister(&tz->device);
1499        return ERR_PTR(result);
1500}
1501EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1502
1503/**
1504 * thermal_device_unregister - removes the registered thermal zone device
1505 * @tz: the thermal zone device to remove
1506 */
1507void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1508{
1509        int i;
1510        const struct thermal_zone_params *tzp;
1511        struct thermal_cooling_device *cdev;
1512        struct thermal_zone_device *pos = NULL;
1513
1514        if (!tz)
1515                return;
1516
1517        tzp = tz->tzp;
1518
1519        mutex_lock(&thermal_list_lock);
1520        list_for_each_entry(pos, &thermal_tz_list, node)
1521            if (pos == tz)
1522                break;
1523        if (pos != tz) {
1524                /* thermal zone device not found */
1525                mutex_unlock(&thermal_list_lock);
1526                return;
1527        }
1528        list_del(&tz->node);
1529
1530        /* Unbind all cdevs associated with 'this' thermal zone */
1531        list_for_each_entry(cdev, &thermal_cdev_list, node) {
1532                if (tz->ops->unbind) {
1533                        tz->ops->unbind(tz, cdev);
1534                        continue;
1535                }
1536
1537                if (!tzp || !tzp->tbp)
1538                        break;
1539
1540                for (i = 0; i < tzp->num_tbps; i++) {
1541                        if (tzp->tbp[i].cdev == cdev) {
1542                                __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1543                                tzp->tbp[i].cdev = NULL;
1544                        }
1545                }
1546        }
1547
1548        mutex_unlock(&thermal_list_lock);
1549
1550        thermal_zone_device_set_polling(tz, 0);
1551
1552        if (tz->type[0])
1553                device_remove_file(&tz->device, &dev_attr_type);
1554        device_remove_file(&tz->device, &dev_attr_temp);
1555        if (tz->ops->get_mode)
1556                device_remove_file(&tz->device, &dev_attr_mode);
1557        device_remove_file(&tz->device, &dev_attr_policy);
1558        remove_trip_attrs(tz);
1559        tz->governor = NULL;
1560
1561        thermal_remove_hwmon_sysfs(tz);
1562        release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
1563        idr_destroy(&tz->idr);
1564        mutex_destroy(&tz->lock);
1565        device_unregister(&tz->device);
1566        return;
1567}
1568EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1569
1570/**
1571 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1572 * @name: thermal zone name to fetch the temperature
1573 *
1574 * When only one zone is found with the passed name, returns a reference to it.
1575 *
1576 * Return: On success returns a reference to an unique thermal zone with
1577 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1578 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1579 */
1580struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1581{
1582        struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1583        unsigned int found = 0;
1584
1585        if (!name)
1586                goto exit;
1587
1588        mutex_lock(&thermal_list_lock);
1589        list_for_each_entry(pos, &thermal_tz_list, node)
1590                if (!strnicmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1591                        found++;
1592                        ref = pos;
1593                }
1594        mutex_unlock(&thermal_list_lock);
1595
1596        /* nothing has been found, thus an error code for it */
1597        if (found == 0)
1598                ref = ERR_PTR(-ENODEV);
1599        else if (found > 1)
1600        /* Success only when an unique zone is found */
1601                ref = ERR_PTR(-EEXIST);
1602
1603exit:
1604        return ref;
1605}
1606EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1607
1608#ifdef CONFIG_NET
1609static struct genl_family thermal_event_genl_family = {
1610        .id = GENL_ID_GENERATE,
1611        .name = THERMAL_GENL_FAMILY_NAME,
1612        .version = THERMAL_GENL_VERSION,
1613        .maxattr = THERMAL_GENL_ATTR_MAX,
1614};
1615
1616static struct genl_multicast_group thermal_event_mcgrp = {
1617        .name = THERMAL_GENL_MCAST_GROUP_NAME,
1618};
1619
1620int thermal_generate_netlink_event(struct thermal_zone_device *tz,
1621                                        enum events event)
1622{
1623        struct sk_buff *skb;
1624        struct nlattr *attr;
1625        struct thermal_genl_event *thermal_event;
1626        void *msg_header;
1627        int size;
1628        int result;
1629        static unsigned int thermal_event_seqnum;
1630
1631        if (!tz)
1632                return -EINVAL;
1633
1634        /* allocate memory */
1635        size = nla_total_size(sizeof(struct thermal_genl_event)) +
1636               nla_total_size(0);
1637
1638        skb = genlmsg_new(size, GFP_ATOMIC);
1639        if (!skb)
1640                return -ENOMEM;
1641
1642        /* add the genetlink message header */
1643        msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++,
1644                                 &thermal_event_genl_family, 0,
1645                                 THERMAL_GENL_CMD_EVENT);
1646        if (!msg_header) {
1647                nlmsg_free(skb);
1648                return -ENOMEM;
1649        }
1650
1651        /* fill the data */
1652        attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT,
1653                           sizeof(struct thermal_genl_event));
1654
1655        if (!attr) {
1656                nlmsg_free(skb);
1657                return -EINVAL;
1658        }
1659
1660        thermal_event = nla_data(attr);
1661        if (!thermal_event) {
1662                nlmsg_free(skb);
1663                return -EINVAL;
1664        }
1665
1666        memset(thermal_event, 0, sizeof(struct thermal_genl_event));
1667
1668        thermal_event->orig = tz->id;
1669        thermal_event->event = event;
1670
1671        /* send multicast genetlink message */
1672        result = genlmsg_end(skb, msg_header);
1673        if (result < 0) {
1674                nlmsg_free(skb);
1675                return result;
1676        }
1677
1678        result = genlmsg_multicast(skb, 0, thermal_event_mcgrp.id, GFP_ATOMIC);
1679        if (result)
1680                dev_err(&tz->device, "Failed to send netlink event:%d", result);
1681
1682        return result;
1683}
1684EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
1685
1686static int genetlink_init(void)
1687{
1688        int result;
1689
1690        result = genl_register_family(&thermal_event_genl_family);
1691        if (result)
1692                return result;
1693
1694        result = genl_register_mc_group(&thermal_event_genl_family,
1695                                        &thermal_event_mcgrp);
1696        if (result)
1697                genl_unregister_family(&thermal_event_genl_family);
1698        return result;
1699}
1700
1701static void genetlink_exit(void)
1702{
1703        genl_unregister_family(&thermal_event_genl_family);
1704}
1705#else /* !CONFIG_NET */
1706static inline int genetlink_init(void) { return 0; }
1707static inline void genetlink_exit(void) {}
1708#endif /* !CONFIG_NET */
1709
1710static int __init thermal_register_governors(void)
1711{
1712        int result;
1713
1714        result = thermal_gov_step_wise_register();
1715        if (result)
1716                return result;
1717
1718        result = thermal_gov_fair_share_register();
1719        if (result)
1720                return result;
1721
1722        return thermal_gov_user_space_register();
1723}
1724
1725static void thermal_unregister_governors(void)
1726{
1727        thermal_gov_step_wise_unregister();
1728        thermal_gov_fair_share_unregister();
1729        thermal_gov_user_space_unregister();
1730}
1731
1732static int __init thermal_init(void)
1733{
1734        int result;
1735
1736        result = thermal_register_governors();
1737        if (result)
1738                goto error;
1739
1740        result = class_register(&thermal_class);
1741        if (result)
1742                goto unregister_governors;
1743
1744        result = genetlink_init();
1745        if (result)
1746                goto unregister_class;
1747
1748        return 0;
1749
1750unregister_governors:
1751        thermal_unregister_governors();
1752unregister_class:
1753        class_unregister(&thermal_class);
1754error:
1755        idr_destroy(&thermal_tz_idr);
1756        idr_destroy(&thermal_cdev_idr);
1757        mutex_destroy(&thermal_idr_lock);
1758        mutex_destroy(&thermal_list_lock);
1759        mutex_destroy(&thermal_governor_lock);
1760        return result;
1761}
1762
1763static void __exit thermal_exit(void)
1764{
1765        genetlink_exit();
1766        class_unregister(&thermal_class);
1767        thermal_unregister_governors();
1768        idr_destroy(&thermal_tz_idr);
1769        idr_destroy(&thermal_cdev_idr);
1770        mutex_destroy(&thermal_idr_lock);
1771        mutex_destroy(&thermal_list_lock);
1772        mutex_destroy(&thermal_governor_lock);
1773}
1774
1775fs_initcall(thermal_init);
1776module_exit(thermal_exit);
1777
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