Merge tag 'for-linus-6.1-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git...
[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         gov = __find_governor(strim(policy));
207         if (!gov)
208                 goto exit;
209
210         ret = thermal_set_governor(tz, gov);
211
212 exit:
213         mutex_unlock(&tz->lock);
214         mutex_unlock(&thermal_governor_lock);
215
216         thermal_notify_tz_gov_change(tz->id, policy);
217
218         return ret;
219 }
220
221 int thermal_build_list_of_policies(char *buf)
222 {
223         struct thermal_governor *pos;
224         ssize_t count = 0;
225
226         mutex_lock(&thermal_governor_lock);
227
228         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
229                 count += scnprintf(buf + count, PAGE_SIZE - count, "%s ",
230                                    pos->name);
231         }
232         count += scnprintf(buf + count, PAGE_SIZE - count, "\n");
233
234         mutex_unlock(&thermal_governor_lock);
235
236         return count;
237 }
238
239 static void __init thermal_unregister_governors(void)
240 {
241         struct thermal_governor **governor;
242
243         for_each_governor_table(governor)
244                 thermal_unregister_governor(*governor);
245 }
246
247 static int __init thermal_register_governors(void)
248 {
249         int ret = 0;
250         struct thermal_governor **governor;
251
252         for_each_governor_table(governor) {
253                 ret = thermal_register_governor(*governor);
254                 if (ret) {
255                         pr_err("Failed to register governor: '%s'",
256                                (*governor)->name);
257                         break;
258                 }
259
260                 pr_info("Registered thermal governor '%s'",
261                         (*governor)->name);
262         }
263
264         if (ret) {
265                 struct thermal_governor **gov;
266
267                 for_each_governor_table(gov) {
268                         if (gov == governor)
269                                 break;
270                         thermal_unregister_governor(*gov);
271                 }
272         }
273
274         return ret;
275 }
276
277 /*
278  * Zone update section: main control loop applied to each zone while monitoring
279  *
280  * in polling mode. The monitoring is done using a workqueue.
281  * Same update may be done on a zone by calling thermal_zone_device_update().
282  *
283  * An update means:
284  * - Non-critical trips will invoke the governor responsible for that zone;
285  * - Hot trips will produce a notification to userspace;
286  * - Critical trip point will cause a system shutdown.
287  */
288 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
289                                             unsigned long delay)
290 {
291         if (delay)
292                 mod_delayed_work(system_freezable_power_efficient_wq,
293                                  &tz->poll_queue, delay);
294         else
295                 cancel_delayed_work(&tz->poll_queue);
296 }
297
298 static void monitor_thermal_zone(struct thermal_zone_device *tz)
299 {
300         if (tz->mode != THERMAL_DEVICE_ENABLED)
301                 thermal_zone_device_set_polling(tz, 0);
302         else if (tz->passive)
303                 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
304         else if (tz->polling_delay_jiffies)
305                 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
306 }
307
308 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
309 {
310         tz->governor ? tz->governor->throttle(tz, trip) :
311                        def_governor->throttle(tz, trip);
312 }
313
314 void thermal_zone_device_critical(struct thermal_zone_device *tz)
315 {
316         /*
317          * poweroff_delay_ms must be a carefully profiled positive value.
318          * Its a must for forced_emergency_poweroff_work to be scheduled.
319          */
320         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
321
322         dev_emerg(&tz->device, "%s: critical temperature reached, "
323                   "shutting down\n", tz->type);
324
325         hw_protection_shutdown("Temperature too high", poweroff_delay_ms);
326 }
327 EXPORT_SYMBOL(thermal_zone_device_critical);
328
329 static void handle_critical_trips(struct thermal_zone_device *tz,
330                                   int trip, int trip_temp, enum thermal_trip_type trip_type)
331 {
332         /* If we have not crossed the trip_temp, we do not care. */
333         if (trip_temp <= 0 || tz->temperature < trip_temp)
334                 return;
335
336         trace_thermal_zone_trip(tz, trip, trip_type);
337
338         if (trip_type == THERMAL_TRIP_HOT && tz->ops->hot)
339                 tz->ops->hot(tz);
340         else if (trip_type == THERMAL_TRIP_CRITICAL)
341                 tz->ops->critical(tz);
342 }
343
344 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
345 {
346         enum thermal_trip_type type;
347         int trip_temp, hyst = 0;
348
349         /* Ignore disabled trip points */
350         if (test_bit(trip, &tz->trips_disabled))
351                 return;
352
353         tz->ops->get_trip_temp(tz, trip, &trip_temp);
354         tz->ops->get_trip_type(tz, trip, &type);
355         if (tz->ops->get_trip_hyst)
356                 tz->ops->get_trip_hyst(tz, trip, &hyst);
357
358         if (tz->last_temperature != THERMAL_TEMP_INVALID) {
359                 if (tz->last_temperature < trip_temp &&
360                     tz->temperature >= trip_temp)
361                         thermal_notify_tz_trip_up(tz->id, trip,
362                                                   tz->temperature);
363                 if (tz->last_temperature >= trip_temp &&
364                     tz->temperature < (trip_temp - hyst))
365                         thermal_notify_tz_trip_down(tz->id, trip,
366                                                     tz->temperature);
367         }
368
369         if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
370                 handle_critical_trips(tz, trip, trip_temp, type);
371         else
372                 handle_non_critical_trips(tz, trip);
373 }
374
375 static void update_temperature(struct thermal_zone_device *tz)
376 {
377         int temp, ret;
378
379         ret = __thermal_zone_get_temp(tz, &temp);
380         if (ret) {
381                 if (ret != -EAGAIN)
382                         dev_warn(&tz->device,
383                                  "failed to read out thermal zone (%d)\n",
384                                  ret);
385                 return;
386         }
387
388         tz->last_temperature = tz->temperature;
389         tz->temperature = temp;
390
391         trace_thermal_temperature(tz);
392
393         thermal_genl_sampling_temp(tz->id, temp);
394 }
395
396 static void thermal_zone_device_init(struct thermal_zone_device *tz)
397 {
398         struct thermal_instance *pos;
399         tz->temperature = THERMAL_TEMP_INVALID;
400         tz->prev_low_trip = -INT_MAX;
401         tz->prev_high_trip = INT_MAX;
402         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
403                 pos->initialized = false;
404 }
405
406 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
407                                         enum thermal_device_mode mode)
408 {
409         int ret = 0;
410
411         mutex_lock(&tz->lock);
412
413         /* do nothing if mode isn't changing */
414         if (mode == tz->mode) {
415                 mutex_unlock(&tz->lock);
416
417                 return ret;
418         }
419
420         if (tz->ops->change_mode)
421                 ret = tz->ops->change_mode(tz, mode);
422
423         if (!ret)
424                 tz->mode = mode;
425
426         mutex_unlock(&tz->lock);
427
428         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
429
430         if (mode == THERMAL_DEVICE_ENABLED)
431                 thermal_notify_tz_enable(tz->id);
432         else
433                 thermal_notify_tz_disable(tz->id);
434
435         return ret;
436 }
437
438 int thermal_zone_device_enable(struct thermal_zone_device *tz)
439 {
440         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
441 }
442 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
443
444 int thermal_zone_device_disable(struct thermal_zone_device *tz)
445 {
446         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
447 }
448 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
449
450 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
451 {
452         lockdep_assert_held(&tz->lock);
453
454         return tz->mode == THERMAL_DEVICE_ENABLED;
455 }
456
457 void thermal_zone_device_update(struct thermal_zone_device *tz,
458                                 enum thermal_notify_event event)
459 {
460         int count;
461
462         if (atomic_read(&in_suspend))
463                 return;
464
465         if (WARN_ONCE(!tz->ops->get_temp, "'%s' must not be called without "
466                       "'get_temp' ops set\n", __func__))
467                 return;
468
469         mutex_lock(&tz->lock);
470
471         if (!thermal_zone_device_is_enabled(tz))
472                 goto out;
473
474         update_temperature(tz);
475
476         __thermal_zone_set_trips(tz);
477
478         tz->notify_event = event;
479
480         for (count = 0; count < tz->num_trips; count++)
481                 handle_thermal_trip(tz, count);
482
483         monitor_thermal_zone(tz);
484 out:
485         mutex_unlock(&tz->lock);
486 }
487 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
488
489 static void thermal_zone_device_check(struct work_struct *work)
490 {
491         struct thermal_zone_device *tz = container_of(work, struct
492                                                       thermal_zone_device,
493                                                       poll_queue.work);
494         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
495 }
496
497 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
498                               void *data)
499 {
500         struct thermal_governor *gov;
501         int ret = 0;
502
503         mutex_lock(&thermal_governor_lock);
504         list_for_each_entry(gov, &thermal_governor_list, governor_list) {
505                 ret = cb(gov, data);
506                 if (ret)
507                         break;
508         }
509         mutex_unlock(&thermal_governor_lock);
510
511         return ret;
512 }
513
514 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
515                                               void *), void *data)
516 {
517         struct thermal_cooling_device *cdev;
518         int ret = 0;
519
520         mutex_lock(&thermal_list_lock);
521         list_for_each_entry(cdev, &thermal_cdev_list, node) {
522                 ret = cb(cdev, data);
523                 if (ret)
524                         break;
525         }
526         mutex_unlock(&thermal_list_lock);
527
528         return ret;
529 }
530
531 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
532                           void *data)
533 {
534         struct thermal_zone_device *tz;
535         int ret = 0;
536
537         mutex_lock(&thermal_list_lock);
538         list_for_each_entry(tz, &thermal_tz_list, node) {
539                 ret = cb(tz, data);
540                 if (ret)
541                         break;
542         }
543         mutex_unlock(&thermal_list_lock);
544
545         return ret;
546 }
547
548 struct thermal_zone_device *thermal_zone_get_by_id(int id)
549 {
550         struct thermal_zone_device *tz, *match = NULL;
551
552         mutex_lock(&thermal_list_lock);
553         list_for_each_entry(tz, &thermal_tz_list, node) {
554                 if (tz->id == id) {
555                         match = tz;
556                         break;
557                 }
558         }
559         mutex_unlock(&thermal_list_lock);
560
561         return match;
562 }
563
564 /*
565  * Device management section: cooling devices, zones devices, and binding
566  *
567  * Set of functions provided by the thermal core for:
568  * - cooling devices lifecycle: registration, unregistration,
569  *                              binding, and unbinding.
570  * - thermal zone devices lifecycle: registration, unregistration,
571  *                                   binding, and unbinding.
572  */
573
574 /**
575  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
576  * @tz:         pointer to struct thermal_zone_device
577  * @trip:       indicates which trip point the cooling devices is
578  *              associated with in this thermal zone.
579  * @cdev:       pointer to struct thermal_cooling_device
580  * @upper:      the Maximum cooling state for this trip point.
581  *              THERMAL_NO_LIMIT means no upper limit,
582  *              and the cooling device can be in max_state.
583  * @lower:      the Minimum cooling state can be used for this trip point.
584  *              THERMAL_NO_LIMIT means no lower limit,
585  *              and the cooling device can be in cooling state 0.
586  * @weight:     The weight of the cooling device to be bound to the
587  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
588  *              default value
589  *
590  * This interface function bind a thermal cooling device to the certain trip
591  * point of a thermal zone device.
592  * This function is usually called in the thermal zone device .bind callback.
593  *
594  * Return: 0 on success, the proper error value otherwise.
595  */
596 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
597                                      int trip,
598                                      struct thermal_cooling_device *cdev,
599                                      unsigned long upper, unsigned long lower,
600                                      unsigned int weight)
601 {
602         struct thermal_instance *dev;
603         struct thermal_instance *pos;
604         struct thermal_zone_device *pos1;
605         struct thermal_cooling_device *pos2;
606         unsigned long max_state;
607         int result, ret;
608
609         if (trip >= tz->num_trips || trip < 0)
610                 return -EINVAL;
611
612         list_for_each_entry(pos1, &thermal_tz_list, node) {
613                 if (pos1 == tz)
614                         break;
615         }
616         list_for_each_entry(pos2, &thermal_cdev_list, node) {
617                 if (pos2 == cdev)
618                         break;
619         }
620
621         if (tz != pos1 || cdev != pos2)
622                 return -EINVAL;
623
624         ret = cdev->ops->get_max_state(cdev, &max_state);
625         if (ret)
626                 return ret;
627
628         /* lower default 0, upper default max_state */
629         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
630         upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
631
632         if (lower > upper || upper > max_state)
633                 return -EINVAL;
634
635         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
636         if (!dev)
637                 return -ENOMEM;
638         dev->tz = tz;
639         dev->cdev = cdev;
640         dev->trip = trip;
641         dev->upper = upper;
642         dev->lower = lower;
643         dev->target = THERMAL_NO_TARGET;
644         dev->weight = weight;
645
646         result = ida_alloc(&tz->ida, GFP_KERNEL);
647         if (result < 0)
648                 goto free_mem;
649
650         dev->id = result;
651         sprintf(dev->name, "cdev%d", dev->id);
652         result =
653             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
654         if (result)
655                 goto release_ida;
656
657         sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
658         sysfs_attr_init(&dev->attr.attr);
659         dev->attr.attr.name = dev->attr_name;
660         dev->attr.attr.mode = 0444;
661         dev->attr.show = trip_point_show;
662         result = device_create_file(&tz->device, &dev->attr);
663         if (result)
664                 goto remove_symbol_link;
665
666         sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
667         sysfs_attr_init(&dev->weight_attr.attr);
668         dev->weight_attr.attr.name = dev->weight_attr_name;
669         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
670         dev->weight_attr.show = weight_show;
671         dev->weight_attr.store = weight_store;
672         result = device_create_file(&tz->device, &dev->weight_attr);
673         if (result)
674                 goto remove_trip_file;
675
676         mutex_lock(&tz->lock);
677         mutex_lock(&cdev->lock);
678         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
679                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
680                         result = -EEXIST;
681                         break;
682                 }
683         if (!result) {
684                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
685                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
686                 atomic_set(&tz->need_update, 1);
687         }
688         mutex_unlock(&cdev->lock);
689         mutex_unlock(&tz->lock);
690
691         if (!result)
692                 return 0;
693
694         device_remove_file(&tz->device, &dev->weight_attr);
695 remove_trip_file:
696         device_remove_file(&tz->device, &dev->attr);
697 remove_symbol_link:
698         sysfs_remove_link(&tz->device.kobj, dev->name);
699 release_ida:
700         ida_free(&tz->ida, dev->id);
701 free_mem:
702         kfree(dev);
703         return result;
704 }
705 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
706
707 /**
708  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
709  *                                        thermal zone.
710  * @tz:         pointer to a struct thermal_zone_device.
711  * @trip:       indicates which trip point the cooling devices is
712  *              associated with in this thermal zone.
713  * @cdev:       pointer to a struct thermal_cooling_device.
714  *
715  * This interface function unbind a thermal cooling device from the certain
716  * trip point of a thermal zone device.
717  * This function is usually called in the thermal zone device .unbind callback.
718  *
719  * Return: 0 on success, the proper error value otherwise.
720  */
721 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
722                                        int trip,
723                                        struct thermal_cooling_device *cdev)
724 {
725         struct thermal_instance *pos, *next;
726
727         mutex_lock(&tz->lock);
728         mutex_lock(&cdev->lock);
729         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
730                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
731                         list_del(&pos->tz_node);
732                         list_del(&pos->cdev_node);
733                         mutex_unlock(&cdev->lock);
734                         mutex_unlock(&tz->lock);
735                         goto unbind;
736                 }
737         }
738         mutex_unlock(&cdev->lock);
739         mutex_unlock(&tz->lock);
740
741         return -ENODEV;
742
743 unbind:
744         device_remove_file(&tz->device, &pos->weight_attr);
745         device_remove_file(&tz->device, &pos->attr);
746         sysfs_remove_link(&tz->device.kobj, pos->name);
747         ida_free(&tz->ida, pos->id);
748         kfree(pos);
749         return 0;
750 }
751 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
752
753 static void thermal_release(struct device *dev)
754 {
755         struct thermal_zone_device *tz;
756         struct thermal_cooling_device *cdev;
757
758         if (!strncmp(dev_name(dev), "thermal_zone",
759                      sizeof("thermal_zone") - 1)) {
760                 tz = to_thermal_zone(dev);
761                 thermal_zone_destroy_device_groups(tz);
762                 kfree(tz);
763         } else if (!strncmp(dev_name(dev), "cooling_device",
764                             sizeof("cooling_device") - 1)) {
765                 cdev = to_cooling_device(dev);
766                 kfree(cdev);
767         }
768 }
769
770 static struct class thermal_class = {
771         .name = "thermal",
772         .dev_release = thermal_release,
773 };
774
775 static inline
776 void print_bind_err_msg(struct thermal_zone_device *tz,
777                         struct thermal_cooling_device *cdev, int ret)
778 {
779         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
780                 tz->type, cdev->type, ret);
781 }
782
783 static void __bind(struct thermal_zone_device *tz, int mask,
784                    struct thermal_cooling_device *cdev,
785                    unsigned long *limits,
786                    unsigned int weight)
787 {
788         int i, ret;
789
790         for (i = 0; i < tz->num_trips; i++) {
791                 if (mask & (1 << i)) {
792                         unsigned long upper, lower;
793
794                         upper = THERMAL_NO_LIMIT;
795                         lower = THERMAL_NO_LIMIT;
796                         if (limits) {
797                                 lower = limits[i * 2];
798                                 upper = limits[i * 2 + 1];
799                         }
800                         ret = thermal_zone_bind_cooling_device(tz, i, cdev,
801                                                                upper, lower,
802                                                                weight);
803                         if (ret)
804                                 print_bind_err_msg(tz, cdev, ret);
805                 }
806         }
807 }
808
809 static void bind_cdev(struct thermal_cooling_device *cdev)
810 {
811         int i, ret;
812         const struct thermal_zone_params *tzp;
813         struct thermal_zone_device *pos = NULL;
814
815         mutex_lock(&thermal_list_lock);
816
817         list_for_each_entry(pos, &thermal_tz_list, node) {
818                 if (!pos->tzp && !pos->ops->bind)
819                         continue;
820
821                 if (pos->ops->bind) {
822                         ret = pos->ops->bind(pos, cdev);
823                         if (ret)
824                                 print_bind_err_msg(pos, cdev, ret);
825                         continue;
826                 }
827
828                 tzp = pos->tzp;
829                 if (!tzp || !tzp->tbp)
830                         continue;
831
832                 for (i = 0; i < tzp->num_tbps; i++) {
833                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
834                                 continue;
835                         if (tzp->tbp[i].match(pos, cdev))
836                                 continue;
837                         tzp->tbp[i].cdev = cdev;
838                         __bind(pos, tzp->tbp[i].trip_mask, cdev,
839                                tzp->tbp[i].binding_limits,
840                                tzp->tbp[i].weight);
841                 }
842         }
843
844         mutex_unlock(&thermal_list_lock);
845 }
846
847 /**
848  * __thermal_cooling_device_register() - register a new thermal cooling device
849  * @np:         a pointer to a device tree node.
850  * @type:       the thermal cooling device type.
851  * @devdata:    device private data.
852  * @ops:                standard thermal cooling devices callbacks.
853  *
854  * This interface function adds a new thermal cooling device (fan/processor/...)
855  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
856  * to all the thermal zone devices registered at the same time.
857  * It also gives the opportunity to link the cooling device to a device tree
858  * node, so that it can be bound to a thermal zone created out of device tree.
859  *
860  * Return: a pointer to the created struct thermal_cooling_device or an
861  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
862  */
863 static struct thermal_cooling_device *
864 __thermal_cooling_device_register(struct device_node *np,
865                                   const char *type, void *devdata,
866                                   const struct thermal_cooling_device_ops *ops)
867 {
868         struct thermal_cooling_device *cdev;
869         struct thermal_zone_device *pos = NULL;
870         int id, ret;
871
872         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
873             !ops->set_cur_state)
874                 return ERR_PTR(-EINVAL);
875
876         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
877         if (!cdev)
878                 return ERR_PTR(-ENOMEM);
879
880         ret = ida_alloc(&thermal_cdev_ida, GFP_KERNEL);
881         if (ret < 0)
882                 goto out_kfree_cdev;
883         cdev->id = ret;
884         id = ret;
885
886         ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
887         if (ret)
888                 goto out_ida_remove;
889
890         cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
891         if (!cdev->type) {
892                 ret = -ENOMEM;
893                 goto out_ida_remove;
894         }
895
896         mutex_init(&cdev->lock);
897         INIT_LIST_HEAD(&cdev->thermal_instances);
898         cdev->np = np;
899         cdev->ops = ops;
900         cdev->updated = false;
901         cdev->device.class = &thermal_class;
902         cdev->devdata = devdata;
903         thermal_cooling_device_setup_sysfs(cdev);
904         ret = device_register(&cdev->device);
905         if (ret)
906                 goto out_kfree_type;
907
908         /* Add 'this' new cdev to the global cdev list */
909         mutex_lock(&thermal_list_lock);
910         list_add(&cdev->node, &thermal_cdev_list);
911         mutex_unlock(&thermal_list_lock);
912
913         /* Update binding information for 'this' new cdev */
914         bind_cdev(cdev);
915
916         mutex_lock(&thermal_list_lock);
917         list_for_each_entry(pos, &thermal_tz_list, node)
918                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
919                         thermal_zone_device_update(pos,
920                                                    THERMAL_EVENT_UNSPECIFIED);
921         mutex_unlock(&thermal_list_lock);
922
923         return cdev;
924
925 out_kfree_type:
926         thermal_cooling_device_destroy_sysfs(cdev);
927         kfree(cdev->type);
928         put_device(&cdev->device);
929         cdev = NULL;
930 out_ida_remove:
931         ida_free(&thermal_cdev_ida, id);
932 out_kfree_cdev:
933         kfree(cdev);
934         return ERR_PTR(ret);
935 }
936
937 /**
938  * thermal_cooling_device_register() - register a new thermal cooling device
939  * @type:       the thermal cooling device type.
940  * @devdata:    device private data.
941  * @ops:                standard thermal cooling devices callbacks.
942  *
943  * This interface function adds a new thermal cooling device (fan/processor/...)
944  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
945  * to all the thermal zone devices registered at the same time.
946  *
947  * Return: a pointer to the created struct thermal_cooling_device or an
948  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
949  */
950 struct thermal_cooling_device *
951 thermal_cooling_device_register(const char *type, void *devdata,
952                                 const struct thermal_cooling_device_ops *ops)
953 {
954         return __thermal_cooling_device_register(NULL, type, devdata, ops);
955 }
956 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
957
958 /**
959  * thermal_of_cooling_device_register() - register an OF thermal cooling device
960  * @np:         a pointer to a device tree node.
961  * @type:       the thermal cooling device type.
962  * @devdata:    device private data.
963  * @ops:                standard thermal cooling devices callbacks.
964  *
965  * This function will register a cooling device with device tree node reference.
966  * This interface function adds a new thermal cooling device (fan/processor/...)
967  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
968  * to all the thermal zone devices registered at the same time.
969  *
970  * Return: a pointer to the created struct thermal_cooling_device or an
971  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
972  */
973 struct thermal_cooling_device *
974 thermal_of_cooling_device_register(struct device_node *np,
975                                    const char *type, void *devdata,
976                                    const struct thermal_cooling_device_ops *ops)
977 {
978         return __thermal_cooling_device_register(np, type, devdata, ops);
979 }
980 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
981
982 static void thermal_cooling_device_release(struct device *dev, void *res)
983 {
984         thermal_cooling_device_unregister(
985                                 *(struct thermal_cooling_device **)res);
986 }
987
988 /**
989  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
990  *                                             device
991  * @dev:        a valid struct device pointer of a sensor device.
992  * @np:         a pointer to a device tree node.
993  * @type:       the thermal cooling device type.
994  * @devdata:    device private data.
995  * @ops:        standard thermal cooling devices callbacks.
996  *
997  * This function will register a cooling device with device tree node reference.
998  * This interface function adds a new thermal cooling device (fan/processor/...)
999  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1000  * to all the thermal zone devices registered at the same time.
1001  *
1002  * Return: a pointer to the created struct thermal_cooling_device or an
1003  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1004  */
1005 struct thermal_cooling_device *
1006 devm_thermal_of_cooling_device_register(struct device *dev,
1007                                 struct device_node *np,
1008                                 char *type, void *devdata,
1009                                 const struct thermal_cooling_device_ops *ops)
1010 {
1011         struct thermal_cooling_device **ptr, *tcd;
1012
1013         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1014                            GFP_KERNEL);
1015         if (!ptr)
1016                 return ERR_PTR(-ENOMEM);
1017
1018         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1019         if (IS_ERR(tcd)) {
1020                 devres_free(ptr);
1021                 return tcd;
1022         }
1023
1024         *ptr = tcd;
1025         devres_add(dev, ptr);
1026
1027         return tcd;
1028 }
1029 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1030
1031 static void __unbind(struct thermal_zone_device *tz, int mask,
1032                      struct thermal_cooling_device *cdev)
1033 {
1034         int i;
1035
1036         for (i = 0; i < tz->num_trips; i++)
1037                 if (mask & (1 << i))
1038                         thermal_zone_unbind_cooling_device(tz, i, cdev);
1039 }
1040
1041 /**
1042  * thermal_cooling_device_unregister - removes a thermal cooling device
1043  * @cdev:       the thermal cooling device to remove.
1044  *
1045  * thermal_cooling_device_unregister() must be called when a registered
1046  * thermal cooling device is no longer needed.
1047  */
1048 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1049 {
1050         int i;
1051         const struct thermal_zone_params *tzp;
1052         struct thermal_zone_device *tz;
1053         struct thermal_cooling_device *pos = NULL;
1054
1055         if (!cdev)
1056                 return;
1057
1058         mutex_lock(&thermal_list_lock);
1059         list_for_each_entry(pos, &thermal_cdev_list, node)
1060                 if (pos == cdev)
1061                         break;
1062         if (pos != cdev) {
1063                 /* thermal cooling device not found */
1064                 mutex_unlock(&thermal_list_lock);
1065                 return;
1066         }
1067         list_del(&cdev->node);
1068
1069         /* Unbind all thermal zones associated with 'this' cdev */
1070         list_for_each_entry(tz, &thermal_tz_list, node) {
1071                 if (tz->ops->unbind) {
1072                         tz->ops->unbind(tz, cdev);
1073                         continue;
1074                 }
1075
1076                 if (!tz->tzp || !tz->tzp->tbp)
1077                         continue;
1078
1079                 tzp = tz->tzp;
1080                 for (i = 0; i < tzp->num_tbps; i++) {
1081                         if (tzp->tbp[i].cdev == cdev) {
1082                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1083                                 tzp->tbp[i].cdev = NULL;
1084                         }
1085                 }
1086         }
1087
1088         mutex_unlock(&thermal_list_lock);
1089
1090         ida_free(&thermal_cdev_ida, cdev->id);
1091         device_del(&cdev->device);
1092         thermal_cooling_device_destroy_sysfs(cdev);
1093         kfree(cdev->type);
1094         put_device(&cdev->device);
1095 }
1096 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1097
1098 static void bind_tz(struct thermal_zone_device *tz)
1099 {
1100         int i, ret;
1101         struct thermal_cooling_device *pos = NULL;
1102         const struct thermal_zone_params *tzp = tz->tzp;
1103
1104         if (!tzp && !tz->ops->bind)
1105                 return;
1106
1107         mutex_lock(&thermal_list_lock);
1108
1109         /* If there is ops->bind, try to use ops->bind */
1110         if (tz->ops->bind) {
1111                 list_for_each_entry(pos, &thermal_cdev_list, node) {
1112                         ret = tz->ops->bind(tz, pos);
1113                         if (ret)
1114                                 print_bind_err_msg(tz, pos, ret);
1115                 }
1116                 goto exit;
1117         }
1118
1119         if (!tzp || !tzp->tbp)
1120                 goto exit;
1121
1122         list_for_each_entry(pos, &thermal_cdev_list, node) {
1123                 for (i = 0; i < tzp->num_tbps; i++) {
1124                         if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1125                                 continue;
1126                         if (tzp->tbp[i].match(tz, pos))
1127                                 continue;
1128                         tzp->tbp[i].cdev = pos;
1129                         __bind(tz, tzp->tbp[i].trip_mask, pos,
1130                                tzp->tbp[i].binding_limits,
1131                                tzp->tbp[i].weight);
1132                 }
1133         }
1134 exit:
1135         mutex_unlock(&thermal_list_lock);
1136 }
1137
1138 static void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms)
1139 {
1140         *delay_jiffies = msecs_to_jiffies(delay_ms);
1141         if (delay_ms > 1000)
1142                 *delay_jiffies = round_jiffies(*delay_jiffies);
1143 }
1144
1145 /**
1146  * thermal_zone_device_register_with_trips() - register a new thermal zone device
1147  * @type:       the thermal zone device type
1148  * @trips:      a pointer to an array of thermal trips
1149  * @num_trips:  the number of trip points the thermal zone support
1150  * @mask:       a bit string indicating the writeablility of trip points
1151  * @devdata:    private device data
1152  * @ops:        standard thermal zone device callbacks
1153  * @tzp:        thermal zone platform parameters
1154  * @passive_delay: number of milliseconds to wait between polls when
1155  *                 performing passive cooling
1156  * @polling_delay: number of milliseconds to wait between polls when checking
1157  *                 whether trip points have been crossed (0 for interrupt
1158  *                 driven systems)
1159  *
1160  * This interface function adds a new thermal zone device (sensor) to
1161  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1162  * thermal cooling devices registered at the same time.
1163  * thermal_zone_device_unregister() must be called when the device is no
1164  * longer needed. The passive cooling depends on the .get_trend() return value.
1165  *
1166  * Return: a pointer to the created struct thermal_zone_device or an
1167  * in case of error, an ERR_PTR. Caller must check return value with
1168  * IS_ERR*() helpers.
1169  */
1170 struct thermal_zone_device *
1171 thermal_zone_device_register_with_trips(const char *type, struct thermal_trip *trips, int num_trips, int mask,
1172                                         void *devdata, struct thermal_zone_device_ops *ops,
1173                                         struct thermal_zone_params *tzp, int passive_delay,
1174                                         int polling_delay)
1175 {
1176         struct thermal_zone_device *tz;
1177         enum thermal_trip_type trip_type;
1178         int trip_temp;
1179         int id;
1180         int result;
1181         int count;
1182         struct thermal_governor *governor;
1183
1184         if (!type || strlen(type) == 0) {
1185                 pr_err("No thermal zone type defined\n");
1186                 return ERR_PTR(-EINVAL);
1187         }
1188
1189         if (strlen(type) >= THERMAL_NAME_LENGTH) {
1190                 pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1191                        type, THERMAL_NAME_LENGTH);
1192                 return ERR_PTR(-EINVAL);
1193         }
1194
1195         /*
1196          * Max trip count can't exceed 31 as the "mask >> num_trips" condition.
1197          * For example, shifting by 32 will result in compiler warning:
1198          * warning: right shift count >= width of type [-Wshift-count- overflow]
1199          *
1200          * Also "mask >> num_trips" will always be true with 32 bit shift.
1201          * E.g. mask = 0x80000000 for trip id 31 to be RW. Then
1202          * mask >> 32 = 0x80000000
1203          * This will result in failure for the below condition.
1204          *
1205          * Check will be true when the bit 31 of the mask is set.
1206          * 32 bit shift will cause overflow of 4 byte integer.
1207          */
1208         if (num_trips > (BITS_PER_TYPE(int) - 1) || num_trips < 0 || mask >> num_trips) {
1209                 pr_err("Incorrect number of thermal trips\n");
1210                 return ERR_PTR(-EINVAL);
1211         }
1212
1213         if (!ops) {
1214                 pr_err("Thermal zone device ops not defined\n");
1215                 return ERR_PTR(-EINVAL);
1216         }
1217
1218         if (num_trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1219                 return ERR_PTR(-EINVAL);
1220
1221         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1222         if (!tz)
1223                 return ERR_PTR(-ENOMEM);
1224
1225         INIT_LIST_HEAD(&tz->thermal_instances);
1226         ida_init(&tz->ida);
1227         mutex_init(&tz->lock);
1228         id = ida_alloc(&thermal_tz_ida, GFP_KERNEL);
1229         if (id < 0) {
1230                 result = id;
1231                 goto free_tz;
1232         }
1233
1234         tz->id = id;
1235         strscpy(tz->type, type, sizeof(tz->type));
1236
1237         result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1238         if (result)
1239                 goto remove_id;
1240
1241         if (!ops->critical)
1242                 ops->critical = thermal_zone_device_critical;
1243
1244         tz->ops = ops;
1245         tz->tzp = tzp;
1246         tz->device.class = &thermal_class;
1247         tz->devdata = devdata;
1248         tz->trips = trips;
1249         tz->num_trips = num_trips;
1250
1251         thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1252         thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1253
1254         /* sys I/F */
1255         /* Add nodes that are always present via .groups */
1256         result = thermal_zone_create_device_groups(tz, mask);
1257         if (result)
1258                 goto remove_id;
1259
1260         /* A new thermal zone needs to be updated anyway. */
1261         atomic_set(&tz->need_update, 1);
1262
1263         result = device_register(&tz->device);
1264         if (result)
1265                 goto release_device;
1266
1267         for (count = 0; count < num_trips; count++) {
1268                 if (tz->ops->get_trip_type(tz, count, &trip_type) ||
1269                     tz->ops->get_trip_temp(tz, count, &trip_temp) ||
1270                     !trip_temp)
1271                         set_bit(count, &tz->trips_disabled);
1272         }
1273
1274         /* Update 'this' zone's governor information */
1275         mutex_lock(&thermal_governor_lock);
1276
1277         if (tz->tzp)
1278                 governor = __find_governor(tz->tzp->governor_name);
1279         else
1280                 governor = def_governor;
1281
1282         result = thermal_set_governor(tz, governor);
1283         if (result) {
1284                 mutex_unlock(&thermal_governor_lock);
1285                 goto unregister;
1286         }
1287
1288         mutex_unlock(&thermal_governor_lock);
1289
1290         if (!tz->tzp || !tz->tzp->no_hwmon) {
1291                 result = thermal_add_hwmon_sysfs(tz);
1292                 if (result)
1293                         goto unregister;
1294         }
1295
1296         mutex_lock(&thermal_list_lock);
1297         list_add_tail(&tz->node, &thermal_tz_list);
1298         mutex_unlock(&thermal_list_lock);
1299
1300         /* Bind cooling devices for this zone */
1301         bind_tz(tz);
1302
1303         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1304
1305         thermal_zone_device_init(tz);
1306         /* Update the new thermal zone and mark it as already updated. */
1307         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1308                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1309
1310         thermal_notify_tz_create(tz->id, tz->type);
1311
1312         return tz;
1313
1314 unregister:
1315         device_del(&tz->device);
1316 release_device:
1317         put_device(&tz->device);
1318         tz = NULL;
1319 remove_id:
1320         ida_free(&thermal_tz_ida, id);
1321 free_tz:
1322         kfree(tz);
1323         return ERR_PTR(result);
1324 }
1325 EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1326
1327 struct thermal_zone_device *thermal_zone_device_register(const char *type, int ntrips, int mask,
1328                                                          void *devdata, struct thermal_zone_device_ops *ops,
1329                                                          struct thermal_zone_params *tzp, int passive_delay,
1330                                                          int polling_delay)
1331 {
1332         return thermal_zone_device_register_with_trips(type, NULL, ntrips, mask,
1333                                                        devdata, ops, tzp,
1334                                                        passive_delay, polling_delay);
1335 }
1336 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1337
1338 /**
1339  * thermal_zone_device_unregister - removes the registered thermal zone device
1340  * @tz: the thermal zone device to remove
1341  */
1342 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1343 {
1344         int i, tz_id;
1345         const struct thermal_zone_params *tzp;
1346         struct thermal_cooling_device *cdev;
1347         struct thermal_zone_device *pos = NULL;
1348
1349         if (!tz)
1350                 return;
1351
1352         tzp = tz->tzp;
1353         tz_id = tz->id;
1354
1355         mutex_lock(&thermal_list_lock);
1356         list_for_each_entry(pos, &thermal_tz_list, node)
1357                 if (pos == tz)
1358                         break;
1359         if (pos != tz) {
1360                 /* thermal zone device not found */
1361                 mutex_unlock(&thermal_list_lock);
1362                 return;
1363         }
1364         list_del(&tz->node);
1365
1366         /* Unbind all cdevs associated with 'this' thermal zone */
1367         list_for_each_entry(cdev, &thermal_cdev_list, node) {
1368                 if (tz->ops->unbind) {
1369                         tz->ops->unbind(tz, cdev);
1370                         continue;
1371                 }
1372
1373                 if (!tzp || !tzp->tbp)
1374                         break;
1375
1376                 for (i = 0; i < tzp->num_tbps; i++) {
1377                         if (tzp->tbp[i].cdev == cdev) {
1378                                 __unbind(tz, tzp->tbp[i].trip_mask, cdev);
1379                                 tzp->tbp[i].cdev = NULL;
1380                         }
1381                 }
1382         }
1383
1384         mutex_unlock(&thermal_list_lock);
1385
1386         cancel_delayed_work_sync(&tz->poll_queue);
1387
1388         thermal_set_governor(tz, NULL);
1389
1390         thermal_remove_hwmon_sysfs(tz);
1391         ida_free(&thermal_tz_ida, tz->id);
1392         ida_destroy(&tz->ida);
1393         mutex_destroy(&tz->lock);
1394         device_unregister(&tz->device);
1395
1396         thermal_notify_tz_delete(tz_id);
1397 }
1398 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1399
1400 /**
1401  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1402  * @name: thermal zone name to fetch the temperature
1403  *
1404  * When only one zone is found with the passed name, returns a reference to it.
1405  *
1406  * Return: On success returns a reference to an unique thermal zone with
1407  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1408  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1409  */
1410 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1411 {
1412         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1413         unsigned int found = 0;
1414
1415         if (!name)
1416                 goto exit;
1417
1418         mutex_lock(&thermal_list_lock);
1419         list_for_each_entry(pos, &thermal_tz_list, node)
1420                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1421                         found++;
1422                         ref = pos;
1423                 }
1424         mutex_unlock(&thermal_list_lock);
1425
1426         /* nothing has been found, thus an error code for it */
1427         if (found == 0)
1428                 ref = ERR_PTR(-ENODEV);
1429         else if (found > 1)
1430         /* Success only when an unique zone is found */
1431                 ref = ERR_PTR(-EEXIST);
1432
1433 exit:
1434         return ref;
1435 }
1436 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1437
1438 static int thermal_pm_notify(struct notifier_block *nb,
1439                              unsigned long mode, void *_unused)
1440 {
1441         struct thermal_zone_device *tz;
1442
1443         switch (mode) {
1444         case PM_HIBERNATION_PREPARE:
1445         case PM_RESTORE_PREPARE:
1446         case PM_SUSPEND_PREPARE:
1447                 atomic_set(&in_suspend, 1);
1448                 break;
1449         case PM_POST_HIBERNATION:
1450         case PM_POST_RESTORE:
1451         case PM_POST_SUSPEND:
1452                 atomic_set(&in_suspend, 0);
1453                 list_for_each_entry(tz, &thermal_tz_list, node) {
1454                         thermal_zone_device_init(tz);
1455                         thermal_zone_device_update(tz,
1456                                                    THERMAL_EVENT_UNSPECIFIED);
1457                 }
1458                 break;
1459         default:
1460                 break;
1461         }
1462         return 0;
1463 }
1464
1465 static struct notifier_block thermal_pm_nb = {
1466         .notifier_call = thermal_pm_notify,
1467 };
1468
1469 static int __init thermal_init(void)
1470 {
1471         int result;
1472
1473         result = thermal_netlink_init();
1474         if (result)
1475                 goto error;
1476
1477         result = thermal_register_governors();
1478         if (result)
1479                 goto error;
1480
1481         result = class_register(&thermal_class);
1482         if (result)
1483                 goto unregister_governors;
1484
1485         result = register_pm_notifier(&thermal_pm_nb);
1486         if (result)
1487                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1488                         result);
1489
1490         return 0;
1491
1492 unregister_governors:
1493         thermal_unregister_governors();
1494 error:
1495         ida_destroy(&thermal_tz_ida);
1496         ida_destroy(&thermal_cdev_ida);
1497         mutex_destroy(&thermal_list_lock);
1498         mutex_destroy(&thermal_governor_lock);
1499         return result;
1500 }
1501 postcore_initcall(thermal_init);