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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 #include <trace/hooks/thermal.h>
25 
26 #define CREATE_TRACE_POINTS
27 #include "thermal_trace.h"
28 
29 #include "thermal_core.h"
30 #include "thermal_hwmon.h"
31 
32 static DEFINE_IDA(thermal_tz_ida);
33 static DEFINE_IDA(thermal_cdev_ida);
34 
35 static LIST_HEAD(thermal_tz_list);
36 static LIST_HEAD(thermal_cdev_list);
37 static LIST_HEAD(thermal_governor_list);
38 
39 static DEFINE_MUTEX(thermal_list_lock);
40 static DEFINE_MUTEX(thermal_governor_lock);
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 
__find_governor(const char * name)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  */
bind_previous_governor(struct thermal_zone_device * tz,const char * failed_gov_name)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  */
thermal_set_governor(struct thermal_zone_device * tz,struct thermal_governor * new_gov)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 
thermal_register_governor(struct thermal_governor * governor)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 
thermal_unregister_governor(struct thermal_governor * governor)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 
thermal_zone_device_set_policy(struct thermal_zone_device * tz,char * policy)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 
thermal_build_list_of_policies(char * buf)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 
thermal_unregister_governors(void)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 
thermal_register_governors(void)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  */
thermal_zone_device_set_polling(struct thermal_zone_device * tz,unsigned long delay)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 
monitor_thermal_zone(struct thermal_zone_device * tz)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 
handle_non_critical_trips(struct thermal_zone_device * tz,int trip)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 
thermal_zone_device_critical(struct thermal_zone_device * tz)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 
handle_critical_trips(struct thermal_zone_device * tz,int trip,int trip_temp,enum thermal_trip_type trip_type)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 
handle_thermal_trip(struct thermal_zone_device * tz,int trip_id)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 (trip.temperature == THERMAL_TEMP_INVALID)
357 		return;
358 
359 	if (tz->last_temperature != THERMAL_TEMP_INVALID) {
360 		if (tz->last_temperature < trip.temperature &&
361 		    tz->temperature >= trip.temperature)
362 			thermal_notify_tz_trip_up(tz->id, trip_id,
363 						  tz->temperature);
364 		if (tz->last_temperature >= trip.temperature &&
365 		    tz->temperature < (trip.temperature - trip.hysteresis))
366 			thermal_notify_tz_trip_down(tz->id, trip_id,
367 						    tz->temperature);
368 	}
369 
370 	if (trip.type == THERMAL_TRIP_CRITICAL || trip.type == THERMAL_TRIP_HOT)
371 		handle_critical_trips(tz, trip_id, trip.temperature, trip.type);
372 	else
373 		handle_non_critical_trips(tz, trip_id);
374 }
375 
update_temperature(struct thermal_zone_device * tz)376 static void update_temperature(struct thermal_zone_device *tz)
377 {
378 	int temp, ret;
379 
380 	ret = __thermal_zone_get_temp(tz, &temp);
381 	if (ret) {
382 		if (ret != -EAGAIN)
383 			dev_warn(&tz->device,
384 				 "failed to read out thermal zone (%d)\n",
385 				 ret);
386 		return;
387 	}
388 
389 	tz->last_temperature = tz->temperature;
390 	tz->temperature = temp;
391 
392 	trace_thermal_temperature(tz);
393 
394 	thermal_genl_sampling_temp(tz->id, temp);
395 }
396 
thermal_zone_device_init(struct thermal_zone_device * tz)397 static void thermal_zone_device_init(struct thermal_zone_device *tz)
398 {
399 	struct thermal_instance *pos;
400 	tz->temperature = THERMAL_TEMP_INVALID;
401 	tz->prev_low_trip = -INT_MAX;
402 	tz->prev_high_trip = INT_MAX;
403 	list_for_each_entry(pos, &tz->thermal_instances, tz_node)
404 		pos->initialized = false;
405 }
406 
__thermal_zone_device_update(struct thermal_zone_device * tz,enum thermal_notify_event event)407 void __thermal_zone_device_update(struct thermal_zone_device *tz,
408 				  enum thermal_notify_event event)
409 {
410 	int count;
411 
412 	if (tz->suspended)
413 		return;
414 
415 	if (WARN_ONCE(!tz->ops->get_temp,
416 		      "'%s' must not be called without 'get_temp' ops set\n",
417 		      __func__))
418 		return;
419 
420 	if (!thermal_zone_device_is_enabled(tz))
421 		return;
422 
423 	update_temperature(tz);
424 
425 	__thermal_zone_set_trips(tz);
426 
427 	tz->notify_event = event;
428 
429 	for (count = 0; count < tz->num_trips; count++)
430 		handle_thermal_trip(tz, count);
431 
432 	monitor_thermal_zone(tz);
433 }
434 
thermal_zone_device_set_mode(struct thermal_zone_device * tz,enum thermal_device_mode mode)435 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
436 					enum thermal_device_mode mode)
437 {
438 	int ret = 0;
439 
440 	mutex_lock(&tz->lock);
441 
442 	/* do nothing if mode isn't changing */
443 	if (mode == tz->mode) {
444 		mutex_unlock(&tz->lock);
445 
446 		return ret;
447 	}
448 
449 	if (!device_is_registered(&tz->device)) {
450 		mutex_unlock(&tz->lock);
451 
452 		return -ENODEV;
453 	}
454 
455 	if (tz->ops->change_mode)
456 		ret = tz->ops->change_mode(tz, mode);
457 
458 	if (!ret)
459 		tz->mode = mode;
460 
461 	__thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
462 
463 	mutex_unlock(&tz->lock);
464 
465 	if (mode == THERMAL_DEVICE_ENABLED)
466 		thermal_notify_tz_enable(tz->id);
467 	else
468 		thermal_notify_tz_disable(tz->id);
469 
470 	return ret;
471 }
472 
thermal_zone_device_enable(struct thermal_zone_device * tz)473 int thermal_zone_device_enable(struct thermal_zone_device *tz)
474 {
475 	return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
476 }
477 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
478 
thermal_zone_device_disable(struct thermal_zone_device * tz)479 int thermal_zone_device_disable(struct thermal_zone_device *tz)
480 {
481 	return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
482 }
483 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
484 
thermal_zone_device_is_enabled(struct thermal_zone_device * tz)485 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
486 {
487 	lockdep_assert_held(&tz->lock);
488 
489 	return tz->mode == THERMAL_DEVICE_ENABLED;
490 }
491 
thermal_zone_device_update(struct thermal_zone_device * tz,enum thermal_notify_event event)492 void thermal_zone_device_update(struct thermal_zone_device *tz,
493 				enum thermal_notify_event event)
494 {
495 	mutex_lock(&tz->lock);
496 	if (device_is_registered(&tz->device))
497 		__thermal_zone_device_update(tz, event);
498 	mutex_unlock(&tz->lock);
499 }
500 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
501 
502 /**
503  * thermal_zone_device_exec - Run a callback under the zone lock.
504  * @tz: Thermal zone.
505  * @cb: Callback to run.
506  * @data: Data to pass to the callback.
507  */
thermal_zone_device_exec(struct thermal_zone_device * tz,void (* cb)(struct thermal_zone_device *,unsigned long),unsigned long data)508 void thermal_zone_device_exec(struct thermal_zone_device *tz,
509 			      void (*cb)(struct thermal_zone_device *,
510 					 unsigned long),
511 			      unsigned long data)
512 {
513 	mutex_lock(&tz->lock);
514 
515 	cb(tz, data);
516 
517 	mutex_unlock(&tz->lock);
518 }
519 EXPORT_SYMBOL_GPL(thermal_zone_device_exec);
520 
thermal_zone_device_check(struct work_struct * work)521 static void thermal_zone_device_check(struct work_struct *work)
522 {
523 	struct thermal_zone_device *tz = container_of(work, struct
524 						      thermal_zone_device,
525 						      poll_queue.work);
526 	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
527 }
528 
for_each_thermal_governor(int (* cb)(struct thermal_governor *,void *),void * data)529 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
530 			      void *data)
531 {
532 	struct thermal_governor *gov;
533 	int ret = 0;
534 
535 	mutex_lock(&thermal_governor_lock);
536 	list_for_each_entry(gov, &thermal_governor_list, governor_list) {
537 		ret = cb(gov, data);
538 		if (ret)
539 			break;
540 	}
541 	mutex_unlock(&thermal_governor_lock);
542 
543 	return ret;
544 }
545 
for_each_thermal_cooling_device(int (* cb)(struct thermal_cooling_device *,void *),void * data)546 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
547 					      void *), void *data)
548 {
549 	struct thermal_cooling_device *cdev;
550 	int ret = 0;
551 
552 	mutex_lock(&thermal_list_lock);
553 	list_for_each_entry(cdev, &thermal_cdev_list, node) {
554 		ret = cb(cdev, data);
555 		if (ret)
556 			break;
557 	}
558 	mutex_unlock(&thermal_list_lock);
559 
560 	return ret;
561 }
562 
for_each_thermal_zone(int (* cb)(struct thermal_zone_device *,void *),void * data)563 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
564 			  void *data)
565 {
566 	struct thermal_zone_device *tz;
567 	int ret = 0;
568 
569 	mutex_lock(&thermal_list_lock);
570 	list_for_each_entry(tz, &thermal_tz_list, node) {
571 		ret = cb(tz, data);
572 		if (ret)
573 			break;
574 	}
575 	mutex_unlock(&thermal_list_lock);
576 
577 	return ret;
578 }
579 
thermal_zone_get_by_id(int id)580 struct thermal_zone_device *thermal_zone_get_by_id(int id)
581 {
582 	struct thermal_zone_device *tz, *match = NULL;
583 
584 	mutex_lock(&thermal_list_lock);
585 	list_for_each_entry(tz, &thermal_tz_list, node) {
586 		if (tz->id == id) {
587 			match = tz;
588 			break;
589 		}
590 	}
591 	mutex_unlock(&thermal_list_lock);
592 
593 	return match;
594 }
595 
596 /*
597  * Device management section: cooling devices, zones devices, and binding
598  *
599  * Set of functions provided by the thermal core for:
600  * - cooling devices lifecycle: registration, unregistration,
601  *				binding, and unbinding.
602  * - thermal zone devices lifecycle: registration, unregistration,
603  *				     binding, and unbinding.
604  */
605 
606 /**
607  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
608  * @tz:		pointer to struct thermal_zone_device
609  * @trip_index:	indicates which trip point the cooling devices is
610  *		associated with in this thermal zone.
611  * @cdev:	pointer to struct thermal_cooling_device
612  * @upper:	the Maximum cooling state for this trip point.
613  *		THERMAL_NO_LIMIT means no upper limit,
614  *		and the cooling device can be in max_state.
615  * @lower:	the Minimum cooling state can be used for this trip point.
616  *		THERMAL_NO_LIMIT means no lower limit,
617  *		and the cooling device can be in cooling state 0.
618  * @weight:	The weight of the cooling device to be bound to the
619  *		thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
620  *		default value
621  *
622  * This interface function bind a thermal cooling device to the certain trip
623  * point of a thermal zone device.
624  * This function is usually called in the thermal zone device .bind callback.
625  *
626  * Return: 0 on success, the proper error value otherwise.
627  */
thermal_zone_bind_cooling_device(struct thermal_zone_device * tz,int trip_index,struct thermal_cooling_device * cdev,unsigned long upper,unsigned long lower,unsigned int weight)628 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
629 				     int trip_index,
630 				     struct thermal_cooling_device *cdev,
631 				     unsigned long upper, unsigned long lower,
632 				     unsigned int weight)
633 {
634 	struct thermal_instance *dev;
635 	struct thermal_instance *pos;
636 	struct thermal_zone_device *pos1;
637 	struct thermal_cooling_device *pos2;
638 	const struct thermal_trip *trip;
639 	bool upper_no_limit;
640 	int result;
641 
642 	if (trip_index >= tz->num_trips || trip_index < 0)
643 		return -EINVAL;
644 
645 	trip = &tz->trips[trip_index];
646 
647 	list_for_each_entry(pos1, &thermal_tz_list, node) {
648 		if (pos1 == tz)
649 			break;
650 	}
651 	list_for_each_entry(pos2, &thermal_cdev_list, node) {
652 		if (pos2 == cdev)
653 			break;
654 	}
655 
656 	if (tz != pos1 || cdev != pos2)
657 		return -EINVAL;
658 
659 	/* lower default 0, upper default max_state */
660 	lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
661 
662 	if (upper == THERMAL_NO_LIMIT) {
663 		upper = cdev->max_state;
664 		upper_no_limit = true;
665 	} else {
666 		upper_no_limit = false;
667 	}
668 
669 	if (lower > upper || upper > cdev->max_state)
670 		return -EINVAL;
671 
672 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
673 	if (!dev)
674 		return -ENOMEM;
675 	dev->tz = tz;
676 	dev->cdev = cdev;
677 	dev->trip = trip;
678 	dev->upper = upper;
679 	dev->upper_no_limit = upper_no_limit;
680 	dev->lower = lower;
681 	dev->target = THERMAL_NO_TARGET;
682 	dev->weight = weight;
683 
684 	result = ida_alloc(&tz->ida, GFP_KERNEL);
685 	if (result < 0)
686 		goto free_mem;
687 
688 	dev->id = result;
689 	sprintf(dev->name, "cdev%d", dev->id);
690 	result =
691 	    sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
692 	if (result)
693 		goto release_ida;
694 
695 	snprintf(dev->attr_name, sizeof(dev->attr_name), "cdev%d_trip_point",
696 		 dev->id);
697 	sysfs_attr_init(&dev->attr.attr);
698 	dev->attr.attr.name = dev->attr_name;
699 	dev->attr.attr.mode = 0444;
700 	dev->attr.show = trip_point_show;
701 	result = device_create_file(&tz->device, &dev->attr);
702 	if (result)
703 		goto remove_symbol_link;
704 
705 	snprintf(dev->weight_attr_name, sizeof(dev->weight_attr_name),
706 		 "cdev%d_weight", dev->id);
707 	sysfs_attr_init(&dev->weight_attr.attr);
708 	dev->weight_attr.attr.name = dev->weight_attr_name;
709 	dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
710 	dev->weight_attr.show = weight_show;
711 	dev->weight_attr.store = weight_store;
712 	result = device_create_file(&tz->device, &dev->weight_attr);
713 	if (result)
714 		goto remove_trip_file;
715 
716 	mutex_lock(&tz->lock);
717 	mutex_lock(&cdev->lock);
718 	list_for_each_entry(pos, &tz->thermal_instances, tz_node)
719 		if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
720 			result = -EEXIST;
721 			break;
722 		}
723 	if (!result) {
724 		list_add_tail(&dev->tz_node, &tz->thermal_instances);
725 		list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
726 		atomic_set(&tz->need_update, 1);
727 	}
728 	mutex_unlock(&cdev->lock);
729 	mutex_unlock(&tz->lock);
730 
731 	if (!result)
732 		return 0;
733 
734 	device_remove_file(&tz->device, &dev->weight_attr);
735 remove_trip_file:
736 	device_remove_file(&tz->device, &dev->attr);
737 remove_symbol_link:
738 	sysfs_remove_link(&tz->device.kobj, dev->name);
739 release_ida:
740 	ida_free(&tz->ida, dev->id);
741 free_mem:
742 	kfree(dev);
743 	return result;
744 }
745 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
746 
747 /**
748  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
749  *					  thermal zone.
750  * @tz:		pointer to a struct thermal_zone_device.
751  * @trip_index:	indicates which trip point the cooling devices is
752  *		associated with in this thermal zone.
753  * @cdev:	pointer to a struct thermal_cooling_device.
754  *
755  * This interface function unbind a thermal cooling device from the certain
756  * trip point of a thermal zone device.
757  * This function is usually called in the thermal zone device .unbind callback.
758  *
759  * Return: 0 on success, the proper error value otherwise.
760  */
thermal_zone_unbind_cooling_device(struct thermal_zone_device * tz,int trip_index,struct thermal_cooling_device * cdev)761 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
762 				       int trip_index,
763 				       struct thermal_cooling_device *cdev)
764 {
765 	struct thermal_instance *pos, *next;
766 	const struct thermal_trip *trip;
767 
768 	mutex_lock(&tz->lock);
769 	mutex_lock(&cdev->lock);
770 	trip = &tz->trips[trip_index];
771 	list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
772 		if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
773 			list_del(&pos->tz_node);
774 			list_del(&pos->cdev_node);
775 			mutex_unlock(&cdev->lock);
776 			mutex_unlock(&tz->lock);
777 			goto unbind;
778 		}
779 	}
780 	mutex_unlock(&cdev->lock);
781 	mutex_unlock(&tz->lock);
782 
783 	return -ENODEV;
784 
785 unbind:
786 	device_remove_file(&tz->device, &pos->weight_attr);
787 	device_remove_file(&tz->device, &pos->attr);
788 	sysfs_remove_link(&tz->device.kobj, pos->name);
789 	ida_free(&tz->ida, pos->id);
790 	kfree(pos);
791 	return 0;
792 }
793 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
794 
thermal_release(struct device * dev)795 static void thermal_release(struct device *dev)
796 {
797 	struct thermal_zone_device *tz;
798 	struct thermal_cooling_device *cdev;
799 
800 	if (!strncmp(dev_name(dev), "thermal_zone",
801 		     sizeof("thermal_zone") - 1)) {
802 		tz = to_thermal_zone(dev);
803 		thermal_zone_destroy_device_groups(tz);
804 		mutex_destroy(&tz->lock);
805 		kfree(tz);
806 	} else if (!strncmp(dev_name(dev), "cooling_device",
807 			    sizeof("cooling_device") - 1)) {
808 		cdev = to_cooling_device(dev);
809 		thermal_cooling_device_destroy_sysfs(cdev);
810 		kfree(cdev->type);
811 		ida_free(&thermal_cdev_ida, cdev->id);
812 		kfree(cdev);
813 	}
814 }
815 
816 static struct class *thermal_class;
817 
818 static inline
print_bind_err_msg(struct thermal_zone_device * tz,struct thermal_cooling_device * cdev,int ret)819 void print_bind_err_msg(struct thermal_zone_device *tz,
820 			struct thermal_cooling_device *cdev, int ret)
821 {
822 	dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
823 		tz->type, cdev->type, ret);
824 }
825 
bind_cdev(struct thermal_cooling_device * cdev)826 static void bind_cdev(struct thermal_cooling_device *cdev)
827 {
828 	int ret;
829 	struct thermal_zone_device *pos = NULL;
830 
831 	list_for_each_entry(pos, &thermal_tz_list, node) {
832 		if (pos->ops->bind) {
833 			ret = pos->ops->bind(pos, cdev);
834 			if (ret)
835 				print_bind_err_msg(pos, cdev, ret);
836 		}
837 	}
838 }
839 
840 /**
841  * __thermal_cooling_device_register() - register a new thermal cooling device
842  * @np:		a pointer to a device tree node.
843  * @type:	the thermal cooling device type.
844  * @devdata:	device private data.
845  * @ops:		standard thermal cooling devices callbacks.
846  *
847  * This interface function adds a new thermal cooling device (fan/processor/...)
848  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
849  * to all the thermal zone devices registered at the same time.
850  * It also gives the opportunity to link the cooling device to a device tree
851  * node, so that it can be bound to a thermal zone created out of device tree.
852  *
853  * Return: a pointer to the created struct thermal_cooling_device or an
854  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
855  */
856 static struct thermal_cooling_device *
__thermal_cooling_device_register(struct device_node * np,const char * type,void * devdata,const struct thermal_cooling_device_ops * ops)857 __thermal_cooling_device_register(struct device_node *np,
858 				  const char *type, void *devdata,
859 				  const struct thermal_cooling_device_ops *ops)
860 {
861 	struct thermal_cooling_device *cdev;
862 	struct thermal_zone_device *pos = NULL;
863 	int id, ret;
864 
865 	if (!ops || !ops->get_max_state || !ops->get_cur_state ||
866 	    !ops->set_cur_state)
867 		return ERR_PTR(-EINVAL);
868 
869 	if (!thermal_class)
870 		return ERR_PTR(-ENODEV);
871 
872 	cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
873 	if (!cdev)
874 		return ERR_PTR(-ENOMEM);
875 
876 	ret = ida_alloc(&thermal_cdev_ida, GFP_KERNEL);
877 	if (ret < 0)
878 		goto out_kfree_cdev;
879 	cdev->id = ret;
880 	id = ret;
881 
882 	cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
883 	if (!cdev->type) {
884 		ret = -ENOMEM;
885 		goto out_ida_remove;
886 	}
887 
888 	mutex_init(&cdev->lock);
889 	INIT_LIST_HEAD(&cdev->thermal_instances);
890 	cdev->np = np;
891 	cdev->ops = ops;
892 	cdev->updated = false;
893 	cdev->device.class = thermal_class;
894 	cdev->devdata = devdata;
895 
896 	ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
897 	if (ret)
898 		goto out_cdev_type;
899 
900 	thermal_cooling_device_setup_sysfs(cdev);
901 
902 	ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
903 	if (ret)
904 		goto out_cooling_dev;
905 
906 	ret = device_register(&cdev->device);
907 	if (ret) {
908 		/* thermal_release() handles rest of the cleanup */
909 		put_device(&cdev->device);
910 		return ERR_PTR(ret);
911 	}
912 
913 	/* Add 'this' new cdev to the global cdev list */
914 	mutex_lock(&thermal_list_lock);
915 
916 	list_add(&cdev->node, &thermal_cdev_list);
917 
918 	/* Update binding information for 'this' new cdev */
919 	bind_cdev(cdev);
920 
921 	list_for_each_entry(pos, &thermal_tz_list, node)
922 		if (atomic_cmpxchg(&pos->need_update, 1, 0))
923 			thermal_zone_device_update(pos,
924 						   THERMAL_EVENT_UNSPECIFIED);
925 
926 	mutex_unlock(&thermal_list_lock);
927 
928 	return cdev;
929 
930 out_cooling_dev:
931 	thermal_cooling_device_destroy_sysfs(cdev);
932 out_cdev_type:
933 	kfree(cdev->type);
934 out_ida_remove:
935 	ida_free(&thermal_cdev_ida, id);
936 out_kfree_cdev:
937 	kfree(cdev);
938 	return ERR_PTR(ret);
939 }
940 
941 /**
942  * thermal_cooling_device_register() - register a new thermal cooling device
943  * @type:	the thermal cooling device type.
944  * @devdata:	device private data.
945  * @ops:		standard thermal cooling devices callbacks.
946  *
947  * This interface function adds a new thermal cooling device (fan/processor/...)
948  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
949  * to all the thermal zone devices registered at the same time.
950  *
951  * Return: a pointer to the created struct thermal_cooling_device or an
952  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
953  */
954 struct thermal_cooling_device *
thermal_cooling_device_register(const char * type,void * devdata,const struct thermal_cooling_device_ops * ops)955 thermal_cooling_device_register(const char *type, void *devdata,
956 				const struct thermal_cooling_device_ops *ops)
957 {
958 	return __thermal_cooling_device_register(NULL, type, devdata, ops);
959 }
960 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
961 
962 /**
963  * thermal_of_cooling_device_register() - register an OF thermal cooling device
964  * @np:		a pointer to a device tree node.
965  * @type:	the thermal cooling device type.
966  * @devdata:	device private data.
967  * @ops:		standard thermal cooling devices callbacks.
968  *
969  * This function will register a cooling device with device tree node reference.
970  * This interface function adds a new thermal cooling device (fan/processor/...)
971  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
972  * to all the thermal zone devices registered at the same time.
973  *
974  * Return: a pointer to the created struct thermal_cooling_device or an
975  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
976  */
977 struct thermal_cooling_device *
thermal_of_cooling_device_register(struct device_node * np,const char * type,void * devdata,const struct thermal_cooling_device_ops * ops)978 thermal_of_cooling_device_register(struct device_node *np,
979 				   const char *type, void *devdata,
980 				   const struct thermal_cooling_device_ops *ops)
981 {
982 	return __thermal_cooling_device_register(np, type, devdata, ops);
983 }
984 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
985 
thermal_cooling_device_release(struct device * dev,void * res)986 static void thermal_cooling_device_release(struct device *dev, void *res)
987 {
988 	thermal_cooling_device_unregister(
989 				*(struct thermal_cooling_device **)res);
990 }
991 
992 /**
993  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
994  *					       device
995  * @dev:	a valid struct device pointer of a sensor device.
996  * @np:		a pointer to a device tree node.
997  * @type:	the thermal cooling device type.
998  * @devdata:	device private data.
999  * @ops:	standard thermal cooling devices callbacks.
1000  *
1001  * This function will register a cooling device with device tree node reference.
1002  * This interface function adds a new thermal cooling device (fan/processor/...)
1003  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1004  * to all the thermal zone devices registered at the same time.
1005  *
1006  * Return: a pointer to the created struct thermal_cooling_device or an
1007  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1008  */
1009 struct thermal_cooling_device *
devm_thermal_of_cooling_device_register(struct device * dev,struct device_node * np,char * type,void * devdata,const struct thermal_cooling_device_ops * ops)1010 devm_thermal_of_cooling_device_register(struct device *dev,
1011 				struct device_node *np,
1012 				char *type, void *devdata,
1013 				const struct thermal_cooling_device_ops *ops)
1014 {
1015 	struct thermal_cooling_device **ptr, *tcd;
1016 
1017 	ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1018 			   GFP_KERNEL);
1019 	if (!ptr)
1020 		return ERR_PTR(-ENOMEM);
1021 
1022 	tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1023 	if (IS_ERR(tcd)) {
1024 		devres_free(ptr);
1025 		return tcd;
1026 	}
1027 
1028 	*ptr = tcd;
1029 	devres_add(dev, ptr);
1030 
1031 	return tcd;
1032 }
1033 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1034 
thermal_cooling_device_present(struct thermal_cooling_device * cdev)1035 static bool thermal_cooling_device_present(struct thermal_cooling_device *cdev)
1036 {
1037 	struct thermal_cooling_device *pos = NULL;
1038 
1039 	list_for_each_entry(pos, &thermal_cdev_list, node) {
1040 		if (pos == cdev)
1041 			return true;
1042 	}
1043 
1044 	return false;
1045 }
1046 
1047 /**
1048  * thermal_cooling_device_update - Update a cooling device object
1049  * @cdev: Target cooling device.
1050  *
1051  * Update @cdev to reflect a change of the underlying hardware or platform.
1052  *
1053  * Must be called when the maximum cooling state of @cdev becomes invalid and so
1054  * its .get_max_state() callback needs to be run to produce the new maximum
1055  * cooling state value.
1056  */
thermal_cooling_device_update(struct thermal_cooling_device * cdev)1057 void thermal_cooling_device_update(struct thermal_cooling_device *cdev)
1058 {
1059 	struct thermal_instance *ti;
1060 	unsigned long state;
1061 
1062 	if (IS_ERR_OR_NULL(cdev))
1063 		return;
1064 
1065 	/*
1066 	 * Hold thermal_list_lock throughout the update to prevent the device
1067 	 * from going away while being updated.
1068 	 */
1069 	mutex_lock(&thermal_list_lock);
1070 
1071 	if (!thermal_cooling_device_present(cdev))
1072 		goto unlock_list;
1073 
1074 	/*
1075 	 * Update under the cdev lock to prevent the state from being set beyond
1076 	 * the new limit concurrently.
1077 	 */
1078 	mutex_lock(&cdev->lock);
1079 
1080 	if (cdev->ops->get_max_state(cdev, &cdev->max_state))
1081 		goto unlock;
1082 
1083 	thermal_cooling_device_stats_reinit(cdev);
1084 
1085 	list_for_each_entry(ti, &cdev->thermal_instances, cdev_node) {
1086 		if (ti->upper == cdev->max_state)
1087 			continue;
1088 
1089 		if (ti->upper < cdev->max_state) {
1090 			if (ti->upper_no_limit)
1091 				ti->upper = cdev->max_state;
1092 
1093 			continue;
1094 		}
1095 
1096 		ti->upper = cdev->max_state;
1097 		if (ti->lower > ti->upper)
1098 			ti->lower = ti->upper;
1099 
1100 		if (ti->target == THERMAL_NO_TARGET)
1101 			continue;
1102 
1103 		if (ti->target > ti->upper)
1104 			ti->target = ti->upper;
1105 	}
1106 
1107 	if (cdev->ops->get_cur_state(cdev, &state) || state > cdev->max_state)
1108 		goto unlock;
1109 
1110 	thermal_cooling_device_stats_update(cdev, state);
1111 
1112 unlock:
1113 	mutex_unlock(&cdev->lock);
1114 
1115 unlock_list:
1116 	mutex_unlock(&thermal_list_lock);
1117 }
1118 EXPORT_SYMBOL_GPL(thermal_cooling_device_update);
1119 
1120 /**
1121  * thermal_cooling_device_unregister - removes a thermal cooling device
1122  * @cdev:	the thermal cooling device to remove.
1123  *
1124  * thermal_cooling_device_unregister() must be called when a registered
1125  * thermal cooling device is no longer needed.
1126  */
thermal_cooling_device_unregister(struct thermal_cooling_device * cdev)1127 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1128 {
1129 	struct thermal_zone_device *tz;
1130 
1131 	if (!cdev)
1132 		return;
1133 
1134 	mutex_lock(&thermal_list_lock);
1135 
1136 	if (!thermal_cooling_device_present(cdev)) {
1137 		mutex_unlock(&thermal_list_lock);
1138 		return;
1139 	}
1140 
1141 	list_del(&cdev->node);
1142 
1143 	/* Unbind all thermal zones associated with 'this' cdev */
1144 	list_for_each_entry(tz, &thermal_tz_list, node) {
1145 		if (tz->ops->unbind)
1146 			tz->ops->unbind(tz, cdev);
1147 	}
1148 
1149 	mutex_unlock(&thermal_list_lock);
1150 
1151 	device_unregister(&cdev->device);
1152 }
1153 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1154 
bind_tz(struct thermal_zone_device * tz)1155 static void bind_tz(struct thermal_zone_device *tz)
1156 {
1157 	int ret;
1158 	struct thermal_cooling_device *pos = NULL;
1159 
1160 	if (!tz->ops->bind)
1161 		return;
1162 
1163 	mutex_lock(&thermal_list_lock);
1164 
1165 	list_for_each_entry(pos, &thermal_cdev_list, node) {
1166 		ret = tz->ops->bind(tz, pos);
1167 		if (ret)
1168 			print_bind_err_msg(tz, pos, ret);
1169 	}
1170 
1171 	mutex_unlock(&thermal_list_lock);
1172 }
1173 
thermal_set_delay_jiffies(unsigned long * delay_jiffies,int delay_ms)1174 static void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms)
1175 {
1176 	*delay_jiffies = msecs_to_jiffies(delay_ms);
1177 	if (delay_ms > 1000)
1178 		*delay_jiffies = round_jiffies(*delay_jiffies);
1179 }
1180 
thermal_zone_get_crit_temp(struct thermal_zone_device * tz,int * temp)1181 int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp)
1182 {
1183 	int i, ret = -EINVAL;
1184 
1185 	if (tz->ops->get_crit_temp)
1186 		return tz->ops->get_crit_temp(tz, temp);
1187 
1188 	if (!tz->trips)
1189 		return -EINVAL;
1190 
1191 	mutex_lock(&tz->lock);
1192 
1193 	for (i = 0; i < tz->num_trips; i++) {
1194 		if (tz->trips[i].type == THERMAL_TRIP_CRITICAL) {
1195 			*temp = tz->trips[i].temperature;
1196 			ret = 0;
1197 			break;
1198 		}
1199 	}
1200 
1201 	mutex_unlock(&tz->lock);
1202 
1203 	return ret;
1204 }
1205 EXPORT_SYMBOL_GPL(thermal_zone_get_crit_temp);
1206 
1207 /**
1208  * thermal_zone_device_register_with_trips() - register a new thermal zone device
1209  * @type:	the thermal zone device type
1210  * @trips:	a pointer to an array of thermal trips
1211  * @num_trips:	the number of trip points the thermal zone support
1212  * @mask:	a bit string indicating the writeablility of trip points
1213  * @devdata:	private device data
1214  * @ops:	standard thermal zone device callbacks
1215  * @tzp:	thermal zone platform parameters
1216  * @passive_delay: number of milliseconds to wait between polls when
1217  *		   performing passive cooling
1218  * @polling_delay: number of milliseconds to wait between polls when checking
1219  *		   whether trip points have been crossed (0 for interrupt
1220  *		   driven systems)
1221  *
1222  * This interface function adds a new thermal zone device (sensor) to
1223  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1224  * thermal cooling devices registered at the same time.
1225  * thermal_zone_device_unregister() must be called when the device is no
1226  * longer needed. The passive cooling depends on the .get_trend() return value.
1227  *
1228  * Return: a pointer to the created struct thermal_zone_device or an
1229  * in case of error, an ERR_PTR. Caller must check return value with
1230  * IS_ERR*() helpers.
1231  */
1232 struct thermal_zone_device *
thermal_zone_device_register_with_trips(const char * type,struct thermal_trip * trips,int num_trips,int mask,void * devdata,struct thermal_zone_device_ops * ops,const struct thermal_zone_params * tzp,int passive_delay,int polling_delay)1233 thermal_zone_device_register_with_trips(const char *type, struct thermal_trip *trips, int num_trips, int mask,
1234 					void *devdata, struct thermal_zone_device_ops *ops,
1235 					const struct thermal_zone_params *tzp, int passive_delay,
1236 					int polling_delay)
1237 {
1238 	struct thermal_zone_device *tz;
1239 	int id;
1240 	int result;
1241 	int count;
1242 	struct thermal_governor *governor;
1243 
1244 	if (!type || strlen(type) == 0) {
1245 		pr_err("No thermal zone type defined\n");
1246 		return ERR_PTR(-EINVAL);
1247 	}
1248 
1249 	if (strlen(type) >= THERMAL_NAME_LENGTH) {
1250 		pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1251 		       type, THERMAL_NAME_LENGTH);
1252 		return ERR_PTR(-EINVAL);
1253 	}
1254 
1255 	/*
1256 	 * Max trip count can't exceed 31 as the "mask >> num_trips" condition.
1257 	 * For example, shifting by 32 will result in compiler warning:
1258 	 * warning: right shift count >= width of type [-Wshift-count- overflow]
1259 	 *
1260 	 * Also "mask >> num_trips" will always be true with 32 bit shift.
1261 	 * E.g. mask = 0x80000000 for trip id 31 to be RW. Then
1262 	 * mask >> 32 = 0x80000000
1263 	 * This will result in failure for the below condition.
1264 	 *
1265 	 * Check will be true when the bit 31 of the mask is set.
1266 	 * 32 bit shift will cause overflow of 4 byte integer.
1267 	 */
1268 	if (num_trips > (BITS_PER_TYPE(int) - 1) || num_trips < 0 || mask >> num_trips) {
1269 		pr_err("Incorrect number of thermal trips\n");
1270 		return ERR_PTR(-EINVAL);
1271 	}
1272 
1273 	if (!ops) {
1274 		pr_err("Thermal zone device ops not defined\n");
1275 		return ERR_PTR(-EINVAL);
1276 	}
1277 
1278 	if (num_trips > 0 && !trips)
1279 		return ERR_PTR(-EINVAL);
1280 
1281 	if (!thermal_class)
1282 		return ERR_PTR(-ENODEV);
1283 
1284 	tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1285 	if (!tz)
1286 		return ERR_PTR(-ENOMEM);
1287 
1288 	if (tzp) {
1289 		tz->tzp = kmemdup(tzp, sizeof(*tzp), GFP_KERNEL);
1290 		if (!tz->tzp) {
1291 			result = -ENOMEM;
1292 			goto free_tz;
1293 		}
1294 	}
1295 
1296 	INIT_LIST_HEAD(&tz->thermal_instances);
1297 	ida_init(&tz->ida);
1298 	mutex_init(&tz->lock);
1299 	id = ida_alloc(&thermal_tz_ida, GFP_KERNEL);
1300 	if (id < 0) {
1301 		result = id;
1302 		goto free_tzp;
1303 	}
1304 
1305 	tz->id = id;
1306 	strscpy(tz->type, type, sizeof(tz->type));
1307 
1308 	if (!ops->critical)
1309 		ops->critical = thermal_zone_device_critical;
1310 
1311 	tz->ops = ops;
1312 	tz->device.class = thermal_class;
1313 	tz->devdata = devdata;
1314 	tz->trips = trips;
1315 	tz->num_trips = num_trips;
1316 
1317 	thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1318 	thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1319 
1320 	/* sys I/F */
1321 	/* Add nodes that are always present via .groups */
1322 	result = thermal_zone_create_device_groups(tz, mask);
1323 	if (result)
1324 		goto remove_id;
1325 
1326 	/* A new thermal zone needs to be updated anyway. */
1327 	atomic_set(&tz->need_update, 1);
1328 
1329 	result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1330 	if (result) {
1331 		thermal_zone_destroy_device_groups(tz);
1332 		goto remove_id;
1333 	}
1334 	result = device_register(&tz->device);
1335 	if (result)
1336 		goto release_device;
1337 
1338 	for (count = 0; count < num_trips; count++) {
1339 		struct thermal_trip trip;
1340 
1341 		result = thermal_zone_get_trip(tz, count, &trip);
1342 		if (result || !trip.temperature)
1343 			set_bit(count, &tz->trips_disabled);
1344 	}
1345 
1346 	/* Update 'this' zone's governor information */
1347 	mutex_lock(&thermal_governor_lock);
1348 
1349 	if (tz->tzp)
1350 		governor = __find_governor(tz->tzp->governor_name);
1351 	else
1352 		governor = def_governor;
1353 
1354 	result = thermal_set_governor(tz, governor);
1355 	if (result) {
1356 		mutex_unlock(&thermal_governor_lock);
1357 		goto unregister;
1358 	}
1359 
1360 	mutex_unlock(&thermal_governor_lock);
1361 
1362 	if (!tz->tzp || !tz->tzp->no_hwmon) {
1363 		result = thermal_add_hwmon_sysfs(tz);
1364 		if (result)
1365 			goto unregister;
1366 	}
1367 
1368 	mutex_lock(&thermal_list_lock);
1369 	list_add_tail(&tz->node, &thermal_tz_list);
1370 	mutex_unlock(&thermal_list_lock);
1371 
1372 	/* Bind cooling devices for this zone */
1373 	bind_tz(tz);
1374 
1375 	INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1376 
1377 	thermal_zone_device_init(tz);
1378 	/* Update the new thermal zone and mark it as already updated. */
1379 	if (atomic_cmpxchg(&tz->need_update, 1, 0))
1380 		thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1381 
1382 	thermal_notify_tz_create(tz->id, tz->type);
1383 
1384 	return tz;
1385 
1386 unregister:
1387 	device_del(&tz->device);
1388 release_device:
1389 	put_device(&tz->device);
1390 remove_id:
1391 	ida_free(&thermal_tz_ida, id);
1392 free_tzp:
1393 	kfree(tz->tzp);
1394 free_tz:
1395 	kfree(tz);
1396 	return ERR_PTR(result);
1397 }
1398 EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1399 
thermal_tripless_zone_device_register(const char * type,void * devdata,struct thermal_zone_device_ops * ops,const struct thermal_zone_params * tzp)1400 struct thermal_zone_device *thermal_tripless_zone_device_register(
1401 					const char *type,
1402 					void *devdata,
1403 					struct thermal_zone_device_ops *ops,
1404 					const struct thermal_zone_params *tzp)
1405 {
1406 	return thermal_zone_device_register_with_trips(type, NULL, 0, 0, devdata,
1407 						       ops, tzp, 0, 0);
1408 }
1409 EXPORT_SYMBOL_GPL(thermal_tripless_zone_device_register);
1410 
thermal_zone_device_priv(struct thermal_zone_device * tzd)1411 void *thermal_zone_device_priv(struct thermal_zone_device *tzd)
1412 {
1413 	return tzd->devdata;
1414 }
1415 EXPORT_SYMBOL_GPL(thermal_zone_device_priv);
1416 
thermal_zone_device_type(struct thermal_zone_device * tzd)1417 const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
1418 {
1419 	return tzd->type;
1420 }
1421 EXPORT_SYMBOL_GPL(thermal_zone_device_type);
1422 
thermal_zone_device_id(struct thermal_zone_device * tzd)1423 int thermal_zone_device_id(struct thermal_zone_device *tzd)
1424 {
1425 	return tzd->id;
1426 }
1427 EXPORT_SYMBOL_GPL(thermal_zone_device_id);
1428 
thermal_zone_device(struct thermal_zone_device * tzd)1429 struct device *thermal_zone_device(struct thermal_zone_device *tzd)
1430 {
1431 	return &tzd->device;
1432 }
1433 EXPORT_SYMBOL_GPL(thermal_zone_device);
1434 
1435 /**
1436  * thermal_zone_device_unregister - removes the registered thermal zone device
1437  * @tz: the thermal zone device to remove
1438  */
thermal_zone_device_unregister(struct thermal_zone_device * tz)1439 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1440 {
1441 	int tz_id;
1442 	struct thermal_cooling_device *cdev;
1443 	struct thermal_zone_device *pos = NULL;
1444 
1445 	if (!tz)
1446 		return;
1447 
1448 	tz_id = tz->id;
1449 
1450 	mutex_lock(&thermal_list_lock);
1451 	list_for_each_entry(pos, &thermal_tz_list, node)
1452 		if (pos == tz)
1453 			break;
1454 	if (pos != tz) {
1455 		/* thermal zone device not found */
1456 		mutex_unlock(&thermal_list_lock);
1457 		return;
1458 	}
1459 	list_del(&tz->node);
1460 
1461 	/* Unbind all cdevs associated with 'this' thermal zone */
1462 	list_for_each_entry(cdev, &thermal_cdev_list, node)
1463 		if (tz->ops->unbind)
1464 			tz->ops->unbind(tz, cdev);
1465 
1466 	mutex_unlock(&thermal_list_lock);
1467 
1468 	cancel_delayed_work_sync(&tz->poll_queue);
1469 
1470 	thermal_set_governor(tz, NULL);
1471 
1472 	thermal_remove_hwmon_sysfs(tz);
1473 	ida_free(&thermal_tz_ida, tz->id);
1474 	ida_destroy(&tz->ida);
1475 
1476 	mutex_lock(&tz->lock);
1477 	device_del(&tz->device);
1478 	mutex_unlock(&tz->lock);
1479 
1480 	kfree(tz->tzp);
1481 
1482 	put_device(&tz->device);
1483 
1484 	thermal_notify_tz_delete(tz_id);
1485 }
1486 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1487 
1488 /**
1489  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1490  * @name: thermal zone name to fetch the temperature
1491  *
1492  * When only one zone is found with the passed name, returns a reference to it.
1493  *
1494  * Return: On success returns a reference to an unique thermal zone with
1495  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1496  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1497  */
thermal_zone_get_zone_by_name(const char * name)1498 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1499 {
1500 	struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1501 	unsigned int found = 0;
1502 
1503 	if (!name)
1504 		goto exit;
1505 
1506 	mutex_lock(&thermal_list_lock);
1507 	list_for_each_entry(pos, &thermal_tz_list, node)
1508 		if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1509 			found++;
1510 			ref = pos;
1511 		}
1512 	mutex_unlock(&thermal_list_lock);
1513 
1514 	/* nothing has been found, thus an error code for it */
1515 	if (found == 0)
1516 		ref = ERR_PTR(-ENODEV);
1517 	else if (found > 1)
1518 	/* Success only when an unique zone is found */
1519 		ref = ERR_PTR(-EEXIST);
1520 
1521 exit:
1522 	return ref;
1523 }
1524 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1525 
thermal_pm_notify(struct notifier_block * nb,unsigned long mode,void * _unused)1526 static int thermal_pm_notify(struct notifier_block *nb,
1527 			     unsigned long mode, void *_unused)
1528 {
1529 	struct thermal_zone_device *tz;
1530 	int irq_wakeable = 0;
1531 
1532 	switch (mode) {
1533 	case PM_HIBERNATION_PREPARE:
1534 	case PM_RESTORE_PREPARE:
1535 	case PM_SUSPEND_PREPARE:
1536 		mutex_lock(&thermal_list_lock);
1537 
1538 		list_for_each_entry(tz, &thermal_tz_list, node) {
1539 			mutex_lock(&tz->lock);
1540 
1541 			trace_android_vh_thermal_pm_notify_suspend(tz, &irq_wakeable);
1542 			if (irq_wakeable) {
1543 				mutex_unlock(&tz->lock);
1544 				continue;
1545 			}
1546 
1547 			tz->suspended = true;
1548 
1549 			mutex_unlock(&tz->lock);
1550 		}
1551 
1552 		mutex_unlock(&thermal_list_lock);
1553 		break;
1554 	case PM_POST_HIBERNATION:
1555 	case PM_POST_RESTORE:
1556 	case PM_POST_SUSPEND:
1557 		mutex_lock(&thermal_list_lock);
1558 
1559 		list_for_each_entry(tz, &thermal_tz_list, node) {
1560 			mutex_lock(&tz->lock);
1561 
1562 			trace_android_vh_thermal_pm_notify_suspend(tz, &irq_wakeable);
1563 			if (irq_wakeable) {
1564 				mutex_unlock(&tz->lock);
1565 				continue;
1566 			}
1567 
1568 			tz->suspended = false;
1569 
1570 			thermal_zone_device_init(tz);
1571 			__thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1572 
1573 			mutex_unlock(&tz->lock);
1574 		}
1575 
1576 		mutex_unlock(&thermal_list_lock);
1577 		break;
1578 	default:
1579 		break;
1580 	}
1581 	return 0;
1582 }
1583 
1584 static struct notifier_block thermal_pm_nb = {
1585 	.notifier_call = thermal_pm_notify,
1586 };
1587 
thermal_init(void)1588 static int __init thermal_init(void)
1589 {
1590 	int result;
1591 
1592 	result = thermal_netlink_init();
1593 	if (result)
1594 		goto error;
1595 
1596 	result = thermal_register_governors();
1597 	if (result)
1598 		goto unregister_netlink;
1599 
1600 	thermal_class = kzalloc(sizeof(*thermal_class), GFP_KERNEL);
1601 	if (!thermal_class) {
1602 		result = -ENOMEM;
1603 		goto unregister_governors;
1604 	}
1605 
1606 	thermal_class->name = "thermal";
1607 	thermal_class->dev_release = thermal_release;
1608 
1609 	result = class_register(thermal_class);
1610 	if (result) {
1611 		kfree(thermal_class);
1612 		thermal_class = NULL;
1613 		goto unregister_governors;
1614 	}
1615 
1616 	result = register_pm_notifier(&thermal_pm_nb);
1617 	if (result)
1618 		pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1619 			result);
1620 
1621 	return 0;
1622 
1623 unregister_governors:
1624 	thermal_unregister_governors();
1625 unregister_netlink:
1626 	thermal_netlink_exit();
1627 error:
1628 	mutex_destroy(&thermal_list_lock);
1629 	mutex_destroy(&thermal_governor_lock);
1630 	return result;
1631 }
1632 postcore_initcall(thermal_init);
1633