Merge back thermal control material for 6.4-rc1.
[platform/kernel/linux-starfive.git] / drivers / thermal / thermal_core.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  thermal.c - Generic Thermal Management Sysfs support.
4  *
5  *  Copyright (C) 2008 Intel Corp
6  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
7  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
8  */
9
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11
12 #include <linux/device.h>
13 #include <linux/err.h>
14 #include <linux/export.h>
15 #include <linux/slab.h>
16 #include <linux/kdev_t.h>
17 #include <linux/idr.h>
18 #include <linux/thermal.h>
19 #include <linux/reboot.h>
20 #include <linux/string.h>
21 #include <linux/of.h>
22 #include <linux/suspend.h>
23
24 #define CREATE_TRACE_POINTS
25 #include <trace/events/thermal.h>
26
27 #include "thermal_core.h"
28 #include "thermal_hwmon.h"
29
30 static DEFINE_IDA(thermal_tz_ida);
31 static DEFINE_IDA(thermal_cdev_ida);
32
33 static LIST_HEAD(thermal_tz_list);
34 static LIST_HEAD(thermal_cdev_list);
35 static LIST_HEAD(thermal_governor_list);
36
37 static DEFINE_MUTEX(thermal_list_lock);
38 static DEFINE_MUTEX(thermal_governor_lock);
39
40 static atomic_t in_suspend;
41
42 static struct thermal_governor *def_governor;
43
44 /*
45  * Governor section: set of functions to handle thermal governors
46  *
47  * Functions to help in the life cycle of thermal governors within
48  * the thermal core and by the thermal governor code.
49  */
50
51 static struct thermal_governor *__find_governor(const char *name)
52 {
53         struct thermal_governor *pos;
54
55         if (!name || !name[0])
56                 return def_governor;
57
58         list_for_each_entry(pos, &thermal_governor_list, governor_list)
59                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
60                         return pos;
61
62         return NULL;
63 }
64
65 /**
66  * bind_previous_governor() - bind the previous governor of the thermal zone
67  * @tz:         a valid pointer to a struct thermal_zone_device
68  * @failed_gov_name:    the name of the governor that failed to register
69  *
70  * Register the previous governor of the thermal zone after a new
71  * governor has failed to be bound.
72  */
73 static void bind_previous_governor(struct thermal_zone_device *tz,
74                                    const char *failed_gov_name)
75 {
76         if (tz->governor && tz->governor->bind_to_tz) {
77                 if (tz->governor->bind_to_tz(tz)) {
78                         dev_err(&tz->device,
79                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
80                                 failed_gov_name, tz->governor->name, tz->type);
81                         tz->governor = NULL;
82                 }
83         }
84 }
85
86 /**
87  * thermal_set_governor() - Switch to another governor
88  * @tz:         a valid pointer to a struct thermal_zone_device
89  * @new_gov:    pointer to the new governor
90  *
91  * Change the governor of thermal zone @tz.
92  *
93  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
94  */
95 static int thermal_set_governor(struct thermal_zone_device *tz,
96                                 struct thermal_governor *new_gov)
97 {
98         int ret = 0;
99
100         if (tz->governor && tz->governor->unbind_from_tz)
101                 tz->governor->unbind_from_tz(tz);
102
103         if (new_gov && new_gov->bind_to_tz) {
104                 ret = new_gov->bind_to_tz(tz);
105                 if (ret) {
106                         bind_previous_governor(tz, new_gov->name);
107
108                         return ret;
109                 }
110         }
111
112         tz->governor = new_gov;
113
114         return ret;
115 }
116
117 int thermal_register_governor(struct thermal_governor *governor)
118 {
119         int err;
120         const char *name;
121         struct thermal_zone_device *pos;
122
123         if (!governor)
124                 return -EINVAL;
125
126         mutex_lock(&thermal_governor_lock);
127
128         err = -EBUSY;
129         if (!__find_governor(governor->name)) {
130                 bool match_default;
131
132                 err = 0;
133                 list_add(&governor->governor_list, &thermal_governor_list);
134                 match_default = !strncmp(governor->name,
135                                          DEFAULT_THERMAL_GOVERNOR,
136                                          THERMAL_NAME_LENGTH);
137
138                 if (!def_governor && match_default)
139                         def_governor = governor;
140         }
141
142         mutex_lock(&thermal_list_lock);
143
144         list_for_each_entry(pos, &thermal_tz_list, node) {
145                 /*
146                  * only thermal zones with specified tz->tzp->governor_name
147                  * may run with tz->govenor unset
148                  */
149                 if (pos->governor)
150                         continue;
151
152                 name = pos->tzp->governor_name;
153
154                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
155                         int ret;
156
157                         ret = thermal_set_governor(pos, governor);
158                         if (ret)
159                                 dev_err(&pos->device,
160                                         "Failed to set governor %s for thermal zone %s: %d\n",
161                                         governor->name, pos->type, ret);
162                 }
163         }
164
165         mutex_unlock(&thermal_list_lock);
166         mutex_unlock(&thermal_governor_lock);
167
168         return err;
169 }
170
171 void thermal_unregister_governor(struct thermal_governor *governor)
172 {
173         struct thermal_zone_device *pos;
174
175         if (!governor)
176                 return;
177
178         mutex_lock(&thermal_governor_lock);
179
180         if (!__find_governor(governor->name))
181                 goto exit;
182
183         mutex_lock(&thermal_list_lock);
184
185         list_for_each_entry(pos, &thermal_tz_list, node) {
186                 if (!strncasecmp(pos->governor->name, governor->name,
187                                  THERMAL_NAME_LENGTH))
188                         thermal_set_governor(pos, NULL);
189         }
190
191         mutex_unlock(&thermal_list_lock);
192         list_del(&governor->governor_list);
193 exit:
194         mutex_unlock(&thermal_governor_lock);
195 }
196
197 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
198                                    char *policy)
199 {
200         struct thermal_governor *gov;
201         int ret = -EINVAL;
202
203         mutex_lock(&thermal_governor_lock);
204         mutex_lock(&tz->lock);
205
206         if (!device_is_registered(&tz->device))
207                 goto exit;
208
209         gov = __find_governor(strim(policy));
210         if (!gov)
211                 goto exit;
212
213         ret = thermal_set_governor(tz, gov);
214
215 exit:
216         mutex_unlock(&tz->lock);
217         mutex_unlock(&thermal_governor_lock);
218
219         thermal_notify_tz_gov_change(tz->id, policy);
220
221         return ret;
222 }
223
224 int thermal_build_list_of_policies(char *buf)
225 {
226         struct thermal_governor *pos;
227         ssize_t count = 0;
228
229         mutex_lock(&thermal_governor_lock);
230
231         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
232                 count += sysfs_emit_at(buf, count, "%s ", pos->name);
233         }
234         count += sysfs_emit_at(buf, count, "\n");
235
236         mutex_unlock(&thermal_governor_lock);
237
238         return count;
239 }
240
241 static void __init thermal_unregister_governors(void)
242 {
243         struct thermal_governor **governor;
244
245         for_each_governor_table(governor)
246                 thermal_unregister_governor(*governor);
247 }
248
249 static int __init thermal_register_governors(void)
250 {
251         int ret = 0;
252         struct thermal_governor **governor;
253
254         for_each_governor_table(governor) {
255                 ret = thermal_register_governor(*governor);
256                 if (ret) {
257                         pr_err("Failed to register governor: '%s'",
258                                (*governor)->name);
259                         break;
260                 }
261
262                 pr_info("Registered thermal governor '%s'",
263                         (*governor)->name);
264         }
265
266         if (ret) {
267                 struct thermal_governor **gov;
268
269                 for_each_governor_table(gov) {
270                         if (gov == governor)
271                                 break;
272                         thermal_unregister_governor(*gov);
273                 }
274         }
275
276         return ret;
277 }
278
279 /*
280  * Zone update section: main control loop applied to each zone while monitoring
281  *
282  * in polling mode. The monitoring is done using a workqueue.
283  * Same update may be done on a zone by calling thermal_zone_device_update().
284  *
285  * An update means:
286  * - Non-critical trips will invoke the governor responsible for that zone;
287  * - Hot trips will produce a notification to userspace;
288  * - Critical trip point will cause a system shutdown.
289  */
290 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
291                                             unsigned long delay)
292 {
293         if (delay)
294                 mod_delayed_work(system_freezable_power_efficient_wq,
295                                  &tz->poll_queue, delay);
296         else
297                 cancel_delayed_work(&tz->poll_queue);
298 }
299
300 static void monitor_thermal_zone(struct thermal_zone_device *tz)
301 {
302         if (tz->mode != THERMAL_DEVICE_ENABLED)
303                 thermal_zone_device_set_polling(tz, 0);
304         else if (tz->passive)
305                 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
306         else if (tz->polling_delay_jiffies)
307                 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
308 }
309
310 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
311 {
312         tz->governor ? tz->governor->throttle(tz, trip) :
313                        def_governor->throttle(tz, trip);
314 }
315
316 void thermal_zone_device_critical(struct thermal_zone_device *tz)
317 {
318         /*
319          * poweroff_delay_ms must be a carefully profiled positive value.
320          * Its a must for forced_emergency_poweroff_work to be scheduled.
321          */
322         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
323
324         dev_emerg(&tz->device, "%s: critical temperature reached, "
325                   "shutting down\n", tz->type);
326
327         hw_protection_shutdown("Temperature too high", poweroff_delay_ms);
328 }
329 EXPORT_SYMBOL(thermal_zone_device_critical);
330
331 static void handle_critical_trips(struct thermal_zone_device *tz,
332                                   int trip, int trip_temp, enum thermal_trip_type trip_type)
333 {
334         /* If we have not crossed the trip_temp, we do not care. */
335         if (trip_temp <= 0 || tz->temperature < trip_temp)
336                 return;
337
338         trace_thermal_zone_trip(tz, trip, trip_type);
339
340         if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
341                 tz->ops->hot(tz);
342         else if (trip_type == THERMAL_TRIP_CRITICAL)
343                 tz->ops->critical(tz);
344 }
345
346 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip_id)
347 {
348         struct thermal_trip trip;
349
350         /* Ignore disabled trip points */
351         if (test_bit(trip_id, &tz->trips_disabled))
352                 return;
353
354         __thermal_zone_get_trip(tz, trip_id, &trip);
355
356         if (tz->last_temperature != THERMAL_TEMP_INVALID) {
357                 if (tz->last_temperature < trip.temperature &&
358                     tz->temperature >= trip.temperature)
359                         thermal_notify_tz_trip_up(tz->id, trip_id,
360                                                   tz->temperature);
361                 if (tz->last_temperature >= trip.temperature &&
362                     tz->temperature < (trip.temperature - trip.hysteresis))
363                         thermal_notify_tz_trip_down(tz->id, trip_id,
364                                                     tz->temperature);
365         }
366
367         if (trip.type == THERMAL_TRIP_CRITICAL || trip.type == THERMAL_TRIP_HOT)
368                 handle_critical_trips(tz, trip_id, trip.temperature, trip.type);
369         else
370                 handle_non_critical_trips(tz, trip_id);
371 }
372
373 static void update_temperature(struct thermal_zone_device *tz)
374 {
375         int temp, ret;
376
377         ret = __thermal_zone_get_temp(tz, &temp);
378         if (ret) {
379                 if (ret != -EAGAIN)
380                         dev_warn(&tz->device,
381                                  "failed to read out thermal zone (%d)\n",
382                                  ret);
383                 return;
384         }
385
386         tz->last_temperature = tz->temperature;
387         tz->temperature = temp;
388
389         trace_thermal_temperature(tz);
390
391         thermal_genl_sampling_temp(tz->id, temp);
392 }
393
394 static void thermal_zone_device_init(struct thermal_zone_device *tz)
395 {
396         struct thermal_instance *pos;
397         tz->temperature = THERMAL_TEMP_INVALID;
398         tz->prev_low_trip = -INT_MAX;
399         tz->prev_high_trip = INT_MAX;
400         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
401                 pos->initialized = false;
402 }
403
404 void __thermal_zone_device_update(struct thermal_zone_device *tz,
405                                   enum thermal_notify_event event)
406 {
407         int count;
408
409         if (atomic_read(&in_suspend))
410                 return;
411
412         if (WARN_ONCE(!tz->ops->get_temp,
413                       "'%s' must not be called without 'get_temp' ops set\n",
414                       __func__))
415                 return;
416
417         if (!thermal_zone_device_is_enabled(tz))
418                 return;
419
420         update_temperature(tz);
421
422         __thermal_zone_set_trips(tz);
423
424         tz->notify_event = event;
425
426         for (count = 0; count < tz->num_trips; count++)
427                 handle_thermal_trip(tz, count);
428
429         monitor_thermal_zone(tz);
430 }
431
432 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
433                                         enum thermal_device_mode mode)
434 {
435         int ret = 0;
436
437         mutex_lock(&tz->lock);
438
439         /* do nothing if mode isn't changing */
440         if (mode == tz->mode) {
441                 mutex_unlock(&tz->lock);
442
443                 return ret;
444         }
445
446         if (!device_is_registered(&tz->device)) {
447                 mutex_unlock(&tz->lock);
448
449                 return -ENODEV;
450         }
451
452         if (tz->ops->change_mode)
453                 ret = tz->ops->change_mode(tz, mode);
454
455         if (!ret)
456                 tz->mode = mode;
457
458         __thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
459
460         mutex_unlock(&tz->lock);
461
462         if (mode == THERMAL_DEVICE_ENABLED)
463                 thermal_notify_tz_enable(tz->id);
464         else
465                 thermal_notify_tz_disable(tz->id);
466
467         return ret;
468 }
469
470 int thermal_zone_device_enable(struct thermal_zone_device *tz)
471 {
472         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
473 }
474 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
475
476 int thermal_zone_device_disable(struct thermal_zone_device *tz)
477 {
478         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
479 }
480 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
481
482 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
483 {
484         lockdep_assert_held(&tz->lock);
485
486         return tz->mode == THERMAL_DEVICE_ENABLED;
487 }
488
489 void thermal_zone_device_update(struct thermal_zone_device *tz,
490                                 enum thermal_notify_event event)
491 {
492         mutex_lock(&tz->lock);
493         if (device_is_registered(&tz->device))
494                 __thermal_zone_device_update(tz, event);
495         mutex_unlock(&tz->lock);
496 }
497 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
498
499 static void thermal_zone_device_check(struct work_struct *work)
500 {
501         struct thermal_zone_device *tz = container_of(work, struct
502                                                       thermal_zone_device,
503                                                       poll_queue.work);
504         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
505 }
506
507 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
508                               void *data)
509 {
510         struct thermal_governor *gov;
511         int ret = 0;
512
513         mutex_lock(&thermal_governor_lock);
514         list_for_each_entry(gov, &thermal_governor_list, governor_list) {
515                 ret = cb(gov, data);
516                 if (ret)
517                         break;
518         }
519         mutex_unlock(&thermal_governor_lock);
520
521         return ret;
522 }
523
524 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
525                                               void *), void *data)
526 {
527         struct thermal_cooling_device *cdev;
528         int ret = 0;
529
530         mutex_lock(&thermal_list_lock);
531         list_for_each_entry(cdev, &thermal_cdev_list, node) {
532                 ret = cb(cdev, data);
533                 if (ret)
534                         break;
535         }
536         mutex_unlock(&thermal_list_lock);
537
538         return ret;
539 }
540
541 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
542                           void *data)
543 {
544         struct thermal_zone_device *tz;
545         int ret = 0;
546
547         mutex_lock(&thermal_list_lock);
548         list_for_each_entry(tz, &thermal_tz_list, node) {
549                 ret = cb(tz, data);
550                 if (ret)
551                         break;
552         }
553         mutex_unlock(&thermal_list_lock);
554
555         return ret;
556 }
557
558 struct thermal_zone_device *thermal_zone_get_by_id(int id)
559 {
560         struct thermal_zone_device *tz, *match = NULL;
561
562         mutex_lock(&thermal_list_lock);
563         list_for_each_entry(tz, &thermal_tz_list, node) {
564                 if (tz->id == id) {
565                         match = tz;
566                         break;
567                 }
568         }
569         mutex_unlock(&thermal_list_lock);
570
571         return match;
572 }
573
574 /*
575  * Device management section: cooling devices, zones devices, and binding
576  *
577  * Set of functions provided by the thermal core for:
578  * - cooling devices lifecycle: registration, unregistration,
579  *                              binding, and unbinding.
580  * - thermal zone devices lifecycle: registration, unregistration,
581  *                                   binding, and unbinding.
582  */
583
584 /**
585  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
586  * @tz:         pointer to struct thermal_zone_device
587  * @trip:       indicates which trip point the cooling devices is
588  *              associated with in this thermal zone.
589  * @cdev:       pointer to struct thermal_cooling_device
590  * @upper:      the Maximum cooling state for this trip point.
591  *              THERMAL_NO_LIMIT means no upper limit,
592  *              and the cooling device can be in max_state.
593  * @lower:      the Minimum cooling state can be used for this trip point.
594  *              THERMAL_NO_LIMIT means no lower limit,
595  *              and the cooling device can be in cooling state 0.
596  * @weight:     The weight of the cooling device to be bound to the
597  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
598  *              default value
599  *
600  * This interface function bind a thermal cooling device to the certain trip
601  * point of a thermal zone device.
602  * This function is usually called in the thermal zone device .bind callback.
603  *
604  * Return: 0 on success, the proper error value otherwise.
605  */
606 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
607                                      int trip,
608                                      struct thermal_cooling_device *cdev,
609                                      unsigned long upper, unsigned long lower,
610                                      unsigned int weight)
611 {
612         struct thermal_instance *dev;
613         struct thermal_instance *pos;
614         struct thermal_zone_device *pos1;
615         struct thermal_cooling_device *pos2;
616         bool upper_no_limit;
617         int result;
618
619         if (trip >= tz->num_trips || trip < 0)
620                 return -EINVAL;
621
622         list_for_each_entry(pos1, &thermal_tz_list, node) {
623                 if (pos1 == tz)
624                         break;
625         }
626         list_for_each_entry(pos2, &thermal_cdev_list, node) {
627                 if (pos2 == cdev)
628                         break;
629         }
630
631         if (tz != pos1 || cdev != pos2)
632                 return -EINVAL;
633
634         /* lower default 0, upper default max_state */
635         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
636
637         if (upper == THERMAL_NO_LIMIT) {
638                 upper = cdev->max_state;
639                 upper_no_limit = true;
640         } else {
641                 upper_no_limit = false;
642         }
643
644         if (lower > upper || upper > cdev->max_state)
645                 return -EINVAL;
646
647         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
648         if (!dev)
649                 return -ENOMEM;
650         dev->tz = tz;
651         dev->cdev = cdev;
652         dev->trip = trip;
653         dev->upper = upper;
654         dev->upper_no_limit = upper_no_limit;
655         dev->lower = lower;
656         dev->target = THERMAL_NO_TARGET;
657         dev->weight = weight;
658
659         result = ida_alloc(&tz->ida, GFP_KERNEL);
660         if (result < 0)
661                 goto free_mem;
662
663         dev->id = result;
664         sprintf(dev->name, "cdev%d", dev->id);
665         result =
666             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
667         if (result)
668                 goto release_ida;
669
670         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
671         sysfs_attr_init(&dev->attr.attr);
672         dev->attr.attr.name = dev->attr_name;
673         dev->attr.attr.mode = 0444;
674         dev->attr.show = trip_point_show;
675         result = device_create_file(&tz->device, &dev->attr);
676         if (result)
677                 goto remove_symbol_link;
678
679         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
680         sysfs_attr_init(&dev->weight_attr.attr);
681         dev->weight_attr.attr.name = dev->weight_attr_name;
682         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
683         dev->weight_attr.show = weight_show;
684         dev->weight_attr.store = weight_store;
685         result = device_create_file(&tz->device, &dev->weight_attr);
686         if (result)
687                 goto remove_trip_file;
688
689         mutex_lock(&tz->lock);
690         mutex_lock(&cdev->lock);
691         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
692                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
693                         result = -EEXIST;
694                         break;
695                 }
696         if (!result) {
697                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
698                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
699                 atomic_set(&tz->need_update, 1);
700         }
701         mutex_unlock(&cdev->lock);
702         mutex_unlock(&tz->lock);
703
704         if (!result)
705                 return 0;
706
707         device_remove_file(&tz->device, &dev->weight_attr);
708 remove_trip_file:
709         device_remove_file(&tz->device, &dev->attr);
710 remove_symbol_link:
711         sysfs_remove_link(&tz->device.kobj, dev->name);
712 release_ida:
713         ida_free(&tz->ida, dev->id);
714 free_mem:
715         kfree(dev);
716         return result;
717 }
718 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
719
720 /**
721  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
722  *                                        thermal zone.
723  * @tz:         pointer to a struct thermal_zone_device.
724  * @trip:       indicates which trip point the cooling devices is
725  *              associated with in this thermal zone.
726  * @cdev:       pointer to a struct thermal_cooling_device.
727  *
728  * This interface function unbind a thermal cooling device from the certain
729  * trip point of a thermal zone device.
730  * This function is usually called in the thermal zone device .unbind callback.
731  *
732  * Return: 0 on success, the proper error value otherwise.
733  */
734 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
735                                        int trip,
736                                        struct thermal_cooling_device *cdev)
737 {
738         struct thermal_instance *pos, *next;
739
740         mutex_lock(&tz->lock);
741         mutex_lock(&cdev->lock);
742         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
743                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
744                         list_del(&pos->tz_node);
745                         list_del(&pos->cdev_node);
746                         mutex_unlock(&cdev->lock);
747                         mutex_unlock(&tz->lock);
748                         goto unbind;
749                 }
750         }
751         mutex_unlock(&cdev->lock);
752         mutex_unlock(&tz->lock);
753
754         return -ENODEV;
755
756 unbind:
757         device_remove_file(&tz->device, &pos->weight_attr);
758         device_remove_file(&tz->device, &pos->attr);
759         sysfs_remove_link(&tz->device.kobj, pos->name);
760         ida_free(&tz->ida, pos->id);
761         kfree(pos);
762         return 0;
763 }
764 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
765
766 static void thermal_release(struct device *dev)
767 {
768         struct thermal_zone_device *tz;
769         struct thermal_cooling_device *cdev;
770
771         if (!strncmp(dev_name(dev), "thermal_zone",
772                      sizeof("thermal_zone") - 1)) {
773                 tz = to_thermal_zone(dev);
774                 thermal_zone_destroy_device_groups(tz);
775                 mutex_destroy(&tz->lock);
776                 kfree(tz);
777         } else if (!strncmp(dev_name(dev), "cooling_device",
778                             sizeof("cooling_device") - 1)) {
779                 cdev = to_cooling_device(dev);
780                 thermal_cooling_device_destroy_sysfs(cdev);
781                 kfree(cdev->type);
782                 ida_free(&thermal_cdev_ida, cdev->id);
783                 kfree(cdev);
784         }
785 }
786
787 static struct class *thermal_class;
788
789 static inline
790 void print_bind_err_msg(struct thermal_zone_device *tz,
791                         struct thermal_cooling_device *cdev, int ret)
792 {
793         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
794                 tz->type, cdev->type, ret);
795 }
796
797 static void __bind(struct thermal_zone_device *tz, int mask,
798                    struct thermal_cooling_device *cdev,
799                    unsigned long *limits,
800                    unsigned int weight)
801 {
802         int i, ret;
803
804         for (i = 0; i < tz->num_trips; i++) {
805                 if (mask & (1 << i)) {
806                         unsigned long upper, lower;
807
808                         upper = THERMAL_NO_LIMIT;
809                         lower = THERMAL_NO_LIMIT;
810                         if (limits) {
811                                 lower = limits[i * 2];
812                                 upper = limits[i * 2 + 1];
813                         }
814                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
815                                                                upper, lower,
816                                                                weight);
817                         if (ret)
818                                 print_bind_err_msg(tz, cdev, ret);
819                 }
820         }
821 }
822
823 static void bind_cdev(struct thermal_cooling_device *cdev)
824 {
825         int i, ret;
826         const struct thermal_zone_params *tzp;
827         struct thermal_zone_device *pos = NULL;
828
829         mutex_lock(&thermal_list_lock);
830
831         list_for_each_entry(pos, &thermal_tz_list, node) {
832                 if (!pos->tzp && !pos->ops->bind)
833                         continue;
834
835                 if (pos->ops->bind) {
836                         ret = pos->ops->bind(pos, cdev);
837                         if (ret)
838                                 print_bind_err_msg(pos, cdev, ret);
839                         continue;
840                 }
841
842                 tzp = pos->tzp;
843                 if (!tzp || !tzp->tbp)
844                         continue;
845
846                 for (i = 0; i < tzp->num_tbps; i++) {
847                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
848                                 continue;
849                         if (tzp->tbp[i].match(pos, cdev))
850                                 continue;
851                         tzp->tbp[i].cdev = cdev;
852                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
853                                tzp->tbp[i].binding_limits,
854                                tzp->tbp[i].weight);
855                 }
856         }
857
858         mutex_unlock(&thermal_list_lock);
859 }
860
861 /**
862  * __thermal_cooling_device_register() - register a new thermal cooling device
863  * @np:         a pointer to a device tree node.
864  * @type:       the thermal cooling device type.
865  * @devdata:    device private data.
866  * @ops:                standard thermal cooling devices callbacks.
867  *
868  * This interface function adds a new thermal cooling device (fan/processor/...)
869  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
870  * to all the thermal zone devices registered at the same time.
871  * It also gives the opportunity to link the cooling device to a device tree
872  * node, so that it can be bound to a thermal zone created out of device tree.
873  *
874  * Return: a pointer to the created struct thermal_cooling_device or an
875  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
876  */
877 static struct thermal_cooling_device *
878 __thermal_cooling_device_register(struct device_node *np,
879                                   const char *type, void *devdata,
880                                   const struct thermal_cooling_device_ops *ops)
881 {
882         struct thermal_cooling_device *cdev;
883         struct thermal_zone_device *pos = NULL;
884         int id, ret;
885
886         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
887             !ops->set_cur_state)
888                 return ERR_PTR(-EINVAL);
889
890         if (!thermal_class)
891                 return ERR_PTR(-ENODEV);
892
893         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
894         if (!cdev)
895                 return ERR_PTR(-ENOMEM);
896
897         ret = ida_alloc(&thermal_cdev_ida, GFP_KERNEL);
898         if (ret < 0)
899                 goto out_kfree_cdev;
900         cdev->id = ret;
901         id = ret;
902
903         cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
904         if (!cdev->type) {
905                 ret = -ENOMEM;
906                 goto out_ida_remove;
907         }
908
909         mutex_init(&cdev->lock);
910         INIT_LIST_HEAD(&cdev->thermal_instances);
911         cdev->np = np;
912         cdev->ops = ops;
913         cdev->updated = false;
914         cdev->device.class = thermal_class;
915         cdev->devdata = devdata;
916
917         ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
918         if (ret)
919                 goto out_cdev_type;
920
921         thermal_cooling_device_setup_sysfs(cdev);
922
923         ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
924         if (ret)
925                 goto out_cooling_dev;
926
927         ret = device_register(&cdev->device);
928         if (ret) {
929                 /* thermal_release() handles rest of the cleanup */
930                 put_device(&cdev->device);
931                 return ERR_PTR(ret);
932         }
933
934         /* Add 'this' new cdev to the global cdev list */
935         mutex_lock(&thermal_list_lock);
936         list_add(&cdev->node, &thermal_cdev_list);
937         mutex_unlock(&thermal_list_lock);
938
939         /* Update binding information for 'this' new cdev */
940         bind_cdev(cdev);
941
942         mutex_lock(&thermal_list_lock);
943         list_for_each_entry(pos, &thermal_tz_list, node)
944                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
945                         thermal_zone_device_update(pos,
946                                                    THERMAL_EVENT_UNSPECIFIED);
947         mutex_unlock(&thermal_list_lock);
948
949         return cdev;
950
951 out_cooling_dev:
952         thermal_cooling_device_destroy_sysfs(cdev);
953 out_cdev_type:
954         kfree(cdev->type);
955 out_ida_remove:
956         ida_free(&thermal_cdev_ida, id);
957 out_kfree_cdev:
958         kfree(cdev);
959         return ERR_PTR(ret);
960 }
961
962 /**
963  * thermal_cooling_device_register() - register a new thermal cooling device
964  * @type:       the thermal cooling device type.
965  * @devdata:    device private data.
966  * @ops:                standard thermal cooling devices callbacks.
967  *
968  * This interface function adds a new thermal cooling device (fan/processor/...)
969  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
970  * to all the thermal zone devices registered at the same time.
971  *
972  * Return: a pointer to the created struct thermal_cooling_device or an
973  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
974  */
975 struct thermal_cooling_device *
976 thermal_cooling_device_register(const char *type, void *devdata,
977                                 const struct thermal_cooling_device_ops *ops)
978 {
979         return __thermal_cooling_device_register(NULL, type, devdata, ops);
980 }
981 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
982
983 /**
984  * thermal_of_cooling_device_register() - register an OF thermal cooling device
985  * @np:         a pointer to a device tree node.
986  * @type:       the thermal cooling device type.
987  * @devdata:    device private data.
988  * @ops:                standard thermal cooling devices callbacks.
989  *
990  * This function will register a cooling device with device tree node reference.
991  * This interface function adds a new thermal cooling device (fan/processor/...)
992  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
993  * to all the thermal zone devices registered at the same time.
994  *
995  * Return: a pointer to the created struct thermal_cooling_device or an
996  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
997  */
998 struct thermal_cooling_device *
999 thermal_of_cooling_device_register(struct device_node *np,
1000                                    const char *type, void *devdata,
1001                                    const struct thermal_cooling_device_ops *ops)
1002 {
1003         return __thermal_cooling_device_register(np, type, devdata, ops);
1004 }
1005 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1006
1007 static void thermal_cooling_device_release(struct device *dev, void *res)
1008 {
1009         thermal_cooling_device_unregister(
1010                                 *(struct thermal_cooling_device **)res);
1011 }
1012
1013 /**
1014  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1015  *                                             device
1016  * @dev:        a valid struct device pointer of a sensor device.
1017  * @np:         a pointer to a device tree node.
1018  * @type:       the thermal cooling device type.
1019  * @devdata:    device private data.
1020  * @ops:        standard thermal cooling devices callbacks.
1021  *
1022  * This function will register a cooling device with device tree node reference.
1023  * This interface function adds a new thermal cooling device (fan/processor/...)
1024  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1025  * to all the thermal zone devices registered at the same time.
1026  *
1027  * Return: a pointer to the created struct thermal_cooling_device or an
1028  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1029  */
1030 struct thermal_cooling_device *
1031 devm_thermal_of_cooling_device_register(struct device *dev,
1032                                 struct device_node *np,
1033                                 char *type, void *devdata,
1034                                 const struct thermal_cooling_device_ops *ops)
1035 {
1036         struct thermal_cooling_device **ptr, *tcd;
1037
1038         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1039                            GFP_KERNEL);
1040         if (!ptr)
1041                 return ERR_PTR(-ENOMEM);
1042
1043         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1044         if (IS_ERR(tcd)) {
1045                 devres_free(ptr);
1046                 return tcd;
1047         }
1048
1049         *ptr = tcd;
1050         devres_add(dev, ptr);
1051
1052         return tcd;
1053 }
1054 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1055
1056 static bool thermal_cooling_device_present(struct thermal_cooling_device *cdev)
1057 {
1058         struct thermal_cooling_device *pos = NULL;
1059
1060         list_for_each_entry(pos, &thermal_cdev_list, node) {
1061                 if (pos == cdev)
1062                         return true;
1063         }
1064
1065         return false;
1066 }
1067
1068 /**
1069  * thermal_cooling_device_update - Update a cooling device object
1070  * @cdev: Target cooling device.
1071  *
1072  * Update @cdev to reflect a change of the underlying hardware or platform.
1073  *
1074  * Must be called when the maximum cooling state of @cdev becomes invalid and so
1075  * its .get_max_state() callback needs to be run to produce the new maximum
1076  * cooling state value.
1077  */
1078 void thermal_cooling_device_update(struct thermal_cooling_device *cdev)
1079 {
1080         struct thermal_instance *ti;
1081         unsigned long state;
1082
1083         if (IS_ERR_OR_NULL(cdev))
1084                 return;
1085
1086         /*
1087          * Hold thermal_list_lock throughout the update to prevent the device
1088          * from going away while being updated.
1089          */
1090         mutex_lock(&thermal_list_lock);
1091
1092         if (!thermal_cooling_device_present(cdev))
1093                 goto unlock_list;
1094
1095         /*
1096          * Update under the cdev lock to prevent the state from being set beyond
1097          * the new limit concurrently.
1098          */
1099         mutex_lock(&cdev->lock);
1100
1101         if (cdev->ops->get_max_state(cdev, &cdev->max_state))
1102                 goto unlock;
1103
1104         thermal_cooling_device_stats_reinit(cdev);
1105
1106         list_for_each_entry(ti, &cdev->thermal_instances, cdev_node) {
1107                 if (ti->upper == cdev->max_state)
1108                         continue;
1109
1110                 if (ti->upper < cdev->max_state) {
1111                         if (ti->upper_no_limit)
1112                                 ti->upper = cdev->max_state;
1113
1114                         continue;
1115                 }
1116
1117                 ti->upper = cdev->max_state;
1118                 if (ti->lower > ti->upper)
1119                         ti->lower = ti->upper;
1120
1121                 if (ti->target == THERMAL_NO_TARGET)
1122                         continue;
1123
1124                 if (ti->target > ti->upper)
1125                         ti->target = ti->upper;
1126         }
1127
1128         if (cdev->ops->get_cur_state(cdev, &state) || state > cdev->max_state)
1129                 goto unlock;
1130
1131         thermal_cooling_device_stats_update(cdev, state);
1132
1133 unlock:
1134         mutex_unlock(&cdev->lock);
1135
1136 unlock_list:
1137         mutex_unlock(&thermal_list_lock);
1138 }
1139 EXPORT_SYMBOL_GPL(thermal_cooling_device_update);
1140
1141 static void __unbind(struct thermal_zone_device *tz, int mask,
1142                      struct thermal_cooling_device *cdev)
1143 {
1144         int i;
1145
1146         for (i = 0; i < tz->num_trips; i++)
1147                 if (mask & (1 << i))
1148                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1149 }
1150
1151 /**
1152  * thermal_cooling_device_unregister - removes a thermal cooling device
1153  * @cdev:       the thermal cooling device to remove.
1154  *
1155  * thermal_cooling_device_unregister() must be called when a registered
1156  * thermal cooling device is no longer needed.
1157  */
1158 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1159 {
1160         int i;
1161         const struct thermal_zone_params *tzp;
1162         struct thermal_zone_device *tz;
1163
1164         if (!cdev)
1165                 return;
1166
1167         mutex_lock(&thermal_list_lock);
1168
1169         if (!thermal_cooling_device_present(cdev)) {
1170                 mutex_unlock(&thermal_list_lock);
1171                 return;
1172         }
1173
1174         list_del(&cdev->node);
1175
1176         /* Unbind all thermal zones associated with 'this' cdev */
1177         list_for_each_entry(tz, &thermal_tz_list, node) {
1178                 if (tz->ops->unbind) {
1179                         tz->ops->unbind(tz, cdev);
1180                         continue;
1181                 }
1182
1183                 if (!tz->tzp || !tz->tzp->tbp)
1184                         continue;
1185
1186                 tzp = tz->tzp;
1187                 for (i = 0; i < tzp->num_tbps; i++) {
1188                         if (tzp->tbp[i].cdev == cdev) {
1189                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1190                                 tzp->tbp[i].cdev = NULL;
1191                         }
1192                 }
1193         }
1194
1195         mutex_unlock(&thermal_list_lock);
1196
1197         device_unregister(&cdev->device);
1198 }
1199 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1200
1201 static void bind_tz(struct thermal_zone_device *tz)
1202 {
1203         int i, ret;
1204         struct thermal_cooling_device *pos = NULL;
1205         const struct thermal_zone_params *tzp = tz->tzp;
1206
1207         if (!tzp && !tz->ops->bind)
1208                 return;
1209
1210         mutex_lock(&thermal_list_lock);
1211
1212         /* If there is ops->bind, try to use ops->bind */
1213         if (tz->ops->bind) {
1214                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1215                         ret = tz->ops->bind(tz, pos);
1216                         if (ret)
1217                                 print_bind_err_msg(tz, pos, ret);
1218                 }
1219                 goto exit;
1220         }
1221
1222         if (!tzp || !tzp->tbp)
1223                 goto exit;
1224
1225         list_for_each_entry(pos, &thermal_cdev_list, node) {
1226                 for (i = 0; i < tzp->num_tbps; i++) {
1227                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1228                                 continue;
1229                         if (tzp->tbp[i].match(tz, pos))
1230                                 continue;
1231                         tzp->tbp[i].cdev = pos;
1232                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1233                                tzp->tbp[i].binding_limits,
1234                                tzp->tbp[i].weight);
1235                 }
1236         }
1237 exit:
1238         mutex_unlock(&thermal_list_lock);
1239 }
1240
1241 static void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms)
1242 {
1243         *delay_jiffies = msecs_to_jiffies(delay_ms);
1244         if (delay_ms > 1000)
1245                 *delay_jiffies = round_jiffies(*delay_jiffies);
1246 }
1247
1248 int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp)
1249 {
1250         int i, ret = -EINVAL;
1251
1252         if (tz->ops->get_crit_temp)
1253                 return tz->ops->get_crit_temp(tz, temp);
1254
1255         if (!tz->trips)
1256                 return -EINVAL;
1257
1258         mutex_lock(&tz->lock);
1259
1260         for (i = 0; i < tz->num_trips; i++) {
1261                 if (tz->trips[i].type == THERMAL_TRIP_CRITICAL) {
1262                         *temp = tz->trips[i].temperature;
1263                         ret = 0;
1264                         break;
1265                 }
1266         }
1267
1268         mutex_unlock(&tz->lock);
1269
1270         return ret;
1271 }
1272 EXPORT_SYMBOL_GPL(thermal_zone_get_crit_temp);
1273
1274 /**
1275  * thermal_zone_device_register_with_trips() - register a new thermal zone device
1276  * @type:       the thermal zone device type
1277  * @trips:      a pointer to an array of thermal trips
1278  * @num_trips:  the number of trip points the thermal zone support
1279  * @mask:       a bit string indicating the writeablility of trip points
1280  * @devdata:    private device data
1281  * @ops:        standard thermal zone device callbacks
1282  * @tzp:        thermal zone platform parameters
1283  * @passive_delay: number of milliseconds to wait between polls when
1284  *                 performing passive cooling
1285  * @polling_delay: number of milliseconds to wait between polls when checking
1286  *                 whether trip points have been crossed (0 for interrupt
1287  *                 driven systems)
1288  *
1289  * This interface function adds a new thermal zone device (sensor) to
1290  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1291  * thermal cooling devices registered at the same time.
1292  * thermal_zone_device_unregister() must be called when the device is no
1293  * longer needed. The passive cooling depends on the .get_trend() return value.
1294  *
1295  * Return: a pointer to the created struct thermal_zone_device or an
1296  * in case of error, an ERR_PTR. Caller must check return value with
1297  * IS_ERR*() helpers.
1298  */
1299 struct thermal_zone_device *
1300 thermal_zone_device_register_with_trips(const char *type, struct thermal_trip *trips, int num_trips, int mask,
1301                                         void *devdata, struct thermal_zone_device_ops *ops,
1302                                         struct thermal_zone_params *tzp, int passive_delay,
1303                                         int polling_delay)
1304 {
1305         struct thermal_zone_device *tz;
1306         int id;
1307         int result;
1308         int count;
1309         struct thermal_governor *governor;
1310
1311         if (!type || strlen(type) == 0) {
1312                 pr_err("No thermal zone type defined\n");
1313                 return ERR_PTR(-EINVAL);
1314         }
1315
1316         if (strlen(type) >= THERMAL_NAME_LENGTH) {
1317                 pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1318                        type, THERMAL_NAME_LENGTH);
1319                 return ERR_PTR(-EINVAL);
1320         }
1321
1322         /*
1323          * Max trip count can't exceed 31 as the "mask >> num_trips" condition.
1324          * For example, shifting by 32 will result in compiler warning:
1325          * warning: right shift count >= width of type [-Wshift-count- overflow]
1326          *
1327          * Also "mask >> num_trips" will always be true with 32 bit shift.
1328          * E.g. mask = 0x80000000 for trip id 31 to be RW. Then
1329          * mask >> 32 = 0x80000000
1330          * This will result in failure for the below condition.
1331          *
1332          * Check will be true when the bit 31 of the mask is set.
1333          * 32 bit shift will cause overflow of 4 byte integer.
1334          */
1335         if (num_trips > (BITS_PER_TYPE(int) - 1) || num_trips < 0 || mask >> num_trips) {
1336                 pr_err("Incorrect number of thermal trips\n");
1337                 return ERR_PTR(-EINVAL);
1338         }
1339
1340         if (!ops) {
1341                 pr_err("Thermal zone device ops not defined\n");
1342                 return ERR_PTR(-EINVAL);
1343         }
1344
1345         if (num_trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp) && !trips)
1346                 return ERR_PTR(-EINVAL);
1347
1348         if (!thermal_class)
1349                 return ERR_PTR(-ENODEV);
1350
1351         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1352         if (!tz)
1353                 return ERR_PTR(-ENOMEM);
1354
1355         INIT_LIST_HEAD(&tz->thermal_instances);
1356         ida_init(&tz->ida);
1357         mutex_init(&tz->lock);
1358         id = ida_alloc(&thermal_tz_ida, GFP_KERNEL);
1359         if (id < 0) {
1360                 result = id;
1361                 goto free_tz;
1362         }
1363
1364         tz->id = id;
1365         strscpy(tz->type, type, sizeof(tz->type));
1366
1367         if (!ops->critical)
1368                 ops->critical = thermal_zone_device_critical;
1369
1370         tz->ops = ops;
1371         tz->tzp = tzp;
1372         tz->device.class = thermal_class;
1373         tz->devdata = devdata;
1374         tz->trips = trips;
1375         tz->num_trips = num_trips;
1376
1377         thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1378         thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1379
1380         /* sys I/F */
1381         /* Add nodes that are always present via .groups */
1382         result = thermal_zone_create_device_groups(tz, mask);
1383         if (result)
1384                 goto remove_id;
1385
1386         /* A new thermal zone needs to be updated anyway. */
1387         atomic_set(&tz->need_update, 1);
1388
1389         result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1390         if (result) {
1391                 thermal_zone_destroy_device_groups(tz);
1392                 goto remove_id;
1393         }
1394         result = device_register(&tz->device);
1395         if (result)
1396                 goto release_device;
1397
1398         for (count = 0; count < num_trips; count++) {
1399                 struct thermal_trip trip;
1400
1401                 result = thermal_zone_get_trip(tz, count, &trip);
1402                 if (result || !trip.temperature)
1403                         set_bit(count, &tz->trips_disabled);
1404         }
1405
1406         /* Update 'this' zone's governor information */
1407         mutex_lock(&thermal_governor_lock);
1408
1409         if (tz->tzp)
1410                 governor = __find_governor(tz->tzp->governor_name);
1411         else
1412                 governor = def_governor;
1413
1414         result = thermal_set_governor(tz, governor);
1415         if (result) {
1416                 mutex_unlock(&thermal_governor_lock);
1417                 goto unregister;
1418         }
1419
1420         mutex_unlock(&thermal_governor_lock);
1421
1422         if (!tz->tzp || !tz->tzp->no_hwmon) {
1423                 result = thermal_add_hwmon_sysfs(tz);
1424                 if (result)
1425                         goto unregister;
1426         }
1427
1428         mutex_lock(&thermal_list_lock);
1429         list_add_tail(&tz->node, &thermal_tz_list);
1430         mutex_unlock(&thermal_list_lock);
1431
1432         /* Bind cooling devices for this zone */
1433         bind_tz(tz);
1434
1435         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1436
1437         thermal_zone_device_init(tz);
1438         /* Update the new thermal zone and mark it as already updated. */
1439         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1440                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1441
1442         thermal_notify_tz_create(tz->id, tz->type);
1443
1444         return tz;
1445
1446 unregister:
1447         device_del(&tz->device);
1448 release_device:
1449         put_device(&tz->device);
1450         tz = NULL;
1451 remove_id:
1452         ida_free(&thermal_tz_ida, id);
1453 free_tz:
1454         kfree(tz);
1455         return ERR_PTR(result);
1456 }
1457 EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1458
1459 struct thermal_zone_device *thermal_zone_device_register(const char *type, int ntrips, int mask,
1460                                                          void *devdata, struct thermal_zone_device_ops *ops,
1461                                                          struct thermal_zone_params *tzp, int passive_delay,
1462                                                          int polling_delay)
1463 {
1464         return thermal_zone_device_register_with_trips(type, NULL, ntrips, mask,
1465                                                        devdata, ops, tzp,
1466                                                        passive_delay, polling_delay);
1467 }
1468 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1469
1470 void *thermal_zone_device_priv(struct thermal_zone_device *tzd)
1471 {
1472         return tzd->devdata;
1473 }
1474 EXPORT_SYMBOL_GPL(thermal_zone_device_priv);
1475
1476 const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
1477 {
1478         return tzd->type;
1479 }
1480 EXPORT_SYMBOL_GPL(thermal_zone_device_type);
1481
1482 int thermal_zone_device_id(struct thermal_zone_device *tzd)
1483 {
1484         return tzd->id;
1485 }
1486 EXPORT_SYMBOL_GPL(thermal_zone_device_id);
1487
1488 /**
1489  * thermal_zone_device_unregister - removes the registered thermal zone device
1490  * @tz: the thermal zone device to remove
1491  */
1492 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1493 {
1494         int i, tz_id;
1495         const struct thermal_zone_params *tzp;
1496         struct thermal_cooling_device *cdev;
1497         struct thermal_zone_device *pos = NULL;
1498
1499         if (!tz)
1500                 return;
1501
1502         tzp = tz->tzp;
1503         tz_id = tz->id;
1504
1505         mutex_lock(&thermal_list_lock);
1506         list_for_each_entry(pos, &thermal_tz_list, node)
1507                 if (pos == tz)
1508                         break;
1509         if (pos != tz) {
1510                 /* thermal zone device not found */
1511                 mutex_unlock(&thermal_list_lock);
1512                 return;
1513         }
1514         list_del(&tz->node);
1515
1516         /* Unbind all cdevs associated with 'this' thermal zone */
1517         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1518                 if (tz->ops->unbind) {
1519                         tz->ops->unbind(tz, cdev);
1520                         continue;
1521                 }
1522
1523                 if (!tzp || !tzp->tbp)
1524                         break;
1525
1526                 for (i = 0; i < tzp->num_tbps; i++) {
1527                         if (tzp->tbp[i].cdev == cdev) {
1528                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1529                                 tzp->tbp[i].cdev = NULL;
1530                         }
1531                 }
1532         }
1533
1534         mutex_unlock(&thermal_list_lock);
1535
1536         cancel_delayed_work_sync(&tz->poll_queue);
1537
1538         thermal_set_governor(tz, NULL);
1539
1540         thermal_remove_hwmon_sysfs(tz);
1541         ida_free(&thermal_tz_ida, tz->id);
1542         ida_destroy(&tz->ida);
1543
1544         mutex_lock(&tz->lock);
1545         device_del(&tz->device);
1546         mutex_unlock(&tz->lock);
1547
1548         put_device(&tz->device);
1549
1550         thermal_notify_tz_delete(tz_id);
1551 }
1552 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1553
1554 /**
1555  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1556  * @name: thermal zone name to fetch the temperature
1557  *
1558  * When only one zone is found with the passed name, returns a reference to it.
1559  *
1560  * Return: On success returns a reference to an unique thermal zone with
1561  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1562  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1563  */
1564 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1565 {
1566         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1567         unsigned int found = 0;
1568
1569         if (!name)
1570                 goto exit;
1571
1572         mutex_lock(&thermal_list_lock);
1573         list_for_each_entry(pos, &thermal_tz_list, node)
1574                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1575                         found++;
1576                         ref = pos;
1577                 }
1578         mutex_unlock(&thermal_list_lock);
1579
1580         /* nothing has been found, thus an error code for it */
1581         if (found == 0)
1582                 ref = ERR_PTR(-ENODEV);
1583         else if (found > 1)
1584         /* Success only when an unique zone is found */
1585                 ref = ERR_PTR(-EEXIST);
1586
1587 exit:
1588         return ref;
1589 }
1590 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1591
1592 static int thermal_pm_notify(struct notifier_block *nb,
1593                              unsigned long mode, void *_unused)
1594 {
1595         struct thermal_zone_device *tz;
1596
1597         switch (mode) {
1598         case PM_HIBERNATION_PREPARE:
1599         case PM_RESTORE_PREPARE:
1600         case PM_SUSPEND_PREPARE:
1601                 atomic_set(&in_suspend, 1);
1602                 break;
1603         case PM_POST_HIBERNATION:
1604         case PM_POST_RESTORE:
1605         case PM_POST_SUSPEND:
1606                 atomic_set(&in_suspend, 0);
1607                 list_for_each_entry(tz, &thermal_tz_list, node) {
1608                         thermal_zone_device_init(tz);
1609                         thermal_zone_device_update(tz,
1610                                                    THERMAL_EVENT_UNSPECIFIED);
1611                 }
1612                 break;
1613         default:
1614                 break;
1615         }
1616         return 0;
1617 }
1618
1619 static struct notifier_block thermal_pm_nb = {
1620         .notifier_call = thermal_pm_notify,
1621 };
1622
1623 static int __init thermal_init(void)
1624 {
1625         int result;
1626
1627         result = thermal_netlink_init();
1628         if (result)
1629                 goto error;
1630
1631         result = thermal_register_governors();
1632         if (result)
1633                 goto unregister_netlink;
1634
1635         thermal_class = kzalloc(sizeof(*thermal_class), GFP_KERNEL);
1636         if (!thermal_class) {
1637                 result = -ENOMEM;
1638                 goto unregister_governors;
1639         }
1640
1641         thermal_class->name = "thermal";
1642         thermal_class->dev_release = thermal_release;
1643
1644         result = class_register(thermal_class);
1645         if (result) {
1646                 kfree(thermal_class);
1647                 thermal_class = NULL;
1648                 goto unregister_governors;
1649         }
1650
1651         result = register_pm_notifier(&thermal_pm_nb);
1652         if (result)
1653                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1654                         result);
1655
1656         return 0;
1657
1658 unregister_governors:
1659         thermal_unregister_governors();
1660 unregister_netlink:
1661         thermal_netlink_exit();
1662 error:
1663         mutex_destroy(&thermal_list_lock);
1664         mutex_destroy(&thermal_governor_lock);
1665         return result;
1666 }
1667 postcore_initcall(thermal_init);