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/module.h>
13 #include <linux/device.h>
14 #include <linux/err.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 <net/netlink.h>
23 #include <net/genetlink.h>
24 #include <linux/suspend.h>
25 
26 #define CREATE_TRACE_POINTS
27 #include <trace/events/thermal.h>
28 
29 #include "thermal_core.h"
30 #include "thermal_hwmon.h"
31 
32 MODULE_AUTHOR("Zhang Rui");
33 MODULE_DESCRIPTION("Generic thermal management sysfs support");
34 MODULE_LICENSE("GPL v2");
35 
36 static DEFINE_IDA(thermal_tz_ida);
37 static DEFINE_IDA(thermal_cdev_ida);
38 
39 static LIST_HEAD(thermal_tz_list);
40 static LIST_HEAD(thermal_cdev_list);
41 static LIST_HEAD(thermal_governor_list);
42 
43 static DEFINE_MUTEX(thermal_list_lock);
44 static DEFINE_MUTEX(thermal_governor_lock);
45 static DEFINE_MUTEX(poweroff_lock);
46 
47 static atomic_t in_suspend;
48 static bool power_off_triggered;
49 
50 static struct thermal_governor *def_governor;
51 
52 /*
53  * Governor section: set of functions to handle thermal governors
54  *
55  * Functions to help in the life cycle of thermal governors within
56  * the thermal core and by the thermal governor code.
57  */
58 
59 static struct thermal_governor *__find_governor(const char *name)
60 {
61 	struct thermal_governor *pos;
62 
63 	if (!name || !name[0])
64 		return def_governor;
65 
66 	list_for_each_entry(pos, &thermal_governor_list, governor_list)
67 		if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
68 			return pos;
69 
70 	return NULL;
71 }
72 
73 /**
74  * bind_previous_governor() - bind the previous governor of the thermal zone
75  * @tz:		a valid pointer to a struct thermal_zone_device
76  * @failed_gov_name:	the name of the governor that failed to register
77  *
78  * Register the previous governor of the thermal zone after a new
79  * governor has failed to be bound.
80  */
81 static void bind_previous_governor(struct thermal_zone_device *tz,
82 				   const char *failed_gov_name)
83 {
84 	if (tz->governor && tz->governor->bind_to_tz) {
85 		if (tz->governor->bind_to_tz(tz)) {
86 			dev_err(&tz->device,
87 				"governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
88 				failed_gov_name, tz->governor->name, tz->type);
89 			tz->governor = NULL;
90 		}
91 	}
92 }
93 
94 /**
95  * thermal_set_governor() - Switch to another governor
96  * @tz:		a valid pointer to a struct thermal_zone_device
97  * @new_gov:	pointer to the new governor
98  *
99  * Change the governor of thermal zone @tz.
100  *
101  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
102  */
103 static int thermal_set_governor(struct thermal_zone_device *tz,
104 				struct thermal_governor *new_gov)
105 {
106 	int ret = 0;
107 
108 	if (tz->governor && tz->governor->unbind_from_tz)
109 		tz->governor->unbind_from_tz(tz);
110 
111 	if (new_gov && new_gov->bind_to_tz) {
112 		ret = new_gov->bind_to_tz(tz);
113 		if (ret) {
114 			bind_previous_governor(tz, new_gov->name);
115 
116 			return ret;
117 		}
118 	}
119 
120 	tz->governor = new_gov;
121 
122 	return ret;
123 }
124 
125 int thermal_register_governor(struct thermal_governor *governor)
126 {
127 	int err;
128 	const char *name;
129 	struct thermal_zone_device *pos;
130 
131 	if (!governor)
132 		return -EINVAL;
133 
134 	mutex_lock(&thermal_governor_lock);
135 
136 	err = -EBUSY;
137 	if (!__find_governor(governor->name)) {
138 		bool match_default;
139 
140 		err = 0;
141 		list_add(&governor->governor_list, &thermal_governor_list);
142 		match_default = !strncmp(governor->name,
143 					 DEFAULT_THERMAL_GOVERNOR,
144 					 THERMAL_NAME_LENGTH);
145 
146 		if (!def_governor && match_default)
147 			def_governor = governor;
148 	}
149 
150 	mutex_lock(&thermal_list_lock);
151 
152 	list_for_each_entry(pos, &thermal_tz_list, node) {
153 		/*
154 		 * only thermal zones with specified tz->tzp->governor_name
155 		 * may run with tz->govenor unset
156 		 */
157 		if (pos->governor)
158 			continue;
159 
160 		name = pos->tzp->governor_name;
161 
162 		if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
163 			int ret;
164 
165 			ret = thermal_set_governor(pos, governor);
166 			if (ret)
167 				dev_err(&pos->device,
168 					"Failed to set governor %s for thermal zone %s: %d\n",
169 					governor->name, pos->type, ret);
170 		}
171 	}
172 
173 	mutex_unlock(&thermal_list_lock);
174 	mutex_unlock(&thermal_governor_lock);
175 
176 	return err;
177 }
178 
179 void thermal_unregister_governor(struct thermal_governor *governor)
180 {
181 	struct thermal_zone_device *pos;
182 
183 	if (!governor)
184 		return;
185 
186 	mutex_lock(&thermal_governor_lock);
187 
188 	if (!__find_governor(governor->name))
189 		goto exit;
190 
191 	mutex_lock(&thermal_list_lock);
192 
193 	list_for_each_entry(pos, &thermal_tz_list, node) {
194 		if (!strncasecmp(pos->governor->name, governor->name,
195 				 THERMAL_NAME_LENGTH))
196 			thermal_set_governor(pos, NULL);
197 	}
198 
199 	mutex_unlock(&thermal_list_lock);
200 	list_del(&governor->governor_list);
201 exit:
202 	mutex_unlock(&thermal_governor_lock);
203 }
204 
205 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
206 				   char *policy)
207 {
208 	struct thermal_governor *gov;
209 	int ret = -EINVAL;
210 
211 	mutex_lock(&thermal_governor_lock);
212 	mutex_lock(&tz->lock);
213 
214 	gov = __find_governor(strim(policy));
215 	if (!gov)
216 		goto exit;
217 
218 	ret = thermal_set_governor(tz, gov);
219 
220 exit:
221 	mutex_unlock(&tz->lock);
222 	mutex_unlock(&thermal_governor_lock);
223 
224 	return ret;
225 }
226 
227 int thermal_build_list_of_policies(char *buf)
228 {
229 	struct thermal_governor *pos;
230 	ssize_t count = 0;
231 	ssize_t size = PAGE_SIZE;
232 
233 	mutex_lock(&thermal_governor_lock);
234 
235 	list_for_each_entry(pos, &thermal_governor_list, governor_list) {
236 		size = PAGE_SIZE - count;
237 		count += scnprintf(buf + count, size, "%s ", pos->name);
238 	}
239 	count += scnprintf(buf + count, size, "\n");
240 
241 	mutex_unlock(&thermal_governor_lock);
242 
243 	return count;
244 }
245 
246 static void __init thermal_unregister_governors(void)
247 {
248 	struct thermal_governor **governor;
249 
250 	for_each_governor_table(governor)
251 		thermal_unregister_governor(*governor);
252 }
253 
254 static int __init thermal_register_governors(void)
255 {
256 	int ret = 0;
257 	struct thermal_governor **governor;
258 
259 	for_each_governor_table(governor) {
260 		ret = thermal_register_governor(*governor);
261 		if (ret) {
262 			pr_err("Failed to register governor: '%s'",
263 			       (*governor)->name);
264 			break;
265 		}
266 
267 		pr_info("Registered thermal governor '%s'",
268 			(*governor)->name);
269 	}
270 
271 	if (ret) {
272 		struct thermal_governor **gov;
273 
274 		for_each_governor_table(gov) {
275 			if (gov == governor)
276 				break;
277 			thermal_unregister_governor(*gov);
278 		}
279 	}
280 
281 	return ret;
282 }
283 
284 /*
285  * Zone update section: main control loop applied to each zone while monitoring
286  *
287  * in polling mode. The monitoring is done using a workqueue.
288  * Same update may be done on a zone by calling thermal_zone_device_update().
289  *
290  * An update means:
291  * - Non-critical trips will invoke the governor responsible for that zone;
292  * - Hot trips will produce a notification to userspace;
293  * - Critical trip point will cause a system shutdown.
294  */
295 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
296 					    int delay)
297 {
298 	if (delay > 1000)
299 		mod_delayed_work(system_freezable_power_efficient_wq,
300 				 &tz->poll_queue,
301 				 round_jiffies(msecs_to_jiffies(delay)));
302 	else if (delay)
303 		mod_delayed_work(system_freezable_power_efficient_wq,
304 				 &tz->poll_queue,
305 				 msecs_to_jiffies(delay));
306 	else
307 		cancel_delayed_work(&tz->poll_queue);
308 }
309 
310 static void monitor_thermal_zone(struct thermal_zone_device *tz)
311 {
312 	mutex_lock(&tz->lock);
313 
314 	if (tz->passive)
315 		thermal_zone_device_set_polling(tz, tz->passive_delay);
316 	else if (tz->polling_delay)
317 		thermal_zone_device_set_polling(tz, tz->polling_delay);
318 	else
319 		thermal_zone_device_set_polling(tz, 0);
320 
321 	mutex_unlock(&tz->lock);
322 }
323 
324 static void handle_non_critical_trips(struct thermal_zone_device *tz, int trip)
325 {
326 	tz->governor ? tz->governor->throttle(tz, trip) :
327 		       def_governor->throttle(tz, trip);
328 }
329 
330 /**
331  * thermal_emergency_poweroff_func - emergency poweroff work after a known delay
332  * @work: work_struct associated with the emergency poweroff function
333  *
334  * This function is called in very critical situations to force
335  * a kernel poweroff after a configurable timeout value.
336  */
337 static void thermal_emergency_poweroff_func(struct work_struct *work)
338 {
339 	/*
340 	 * We have reached here after the emergency thermal shutdown
341 	 * Waiting period has expired. This means orderly_poweroff has
342 	 * not been able to shut off the system for some reason.
343 	 * Try to shut down the system immediately using kernel_power_off
344 	 * if populated
345 	 */
346 	WARN(1, "Attempting kernel_power_off: Temperature too high\n");
347 	kernel_power_off();
348 
349 	/*
350 	 * Worst of the worst case trigger emergency restart
351 	 */
352 	WARN(1, "Attempting emergency_restart: Temperature too high\n");
353 	emergency_restart();
354 }
355 
356 static DECLARE_DELAYED_WORK(thermal_emergency_poweroff_work,
357 			    thermal_emergency_poweroff_func);
358 
359 /**
360  * thermal_emergency_poweroff - Trigger an emergency system poweroff
361  *
362  * This may be called from any critical situation to trigger a system shutdown
363  * after a known period of time. By default this is not scheduled.
364  */
365 static void thermal_emergency_poweroff(void)
366 {
367 	int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
368 	/*
369 	 * poweroff_delay_ms must be a carefully profiled positive value.
370 	 * Its a must for thermal_emergency_poweroff_work to be scheduled
371 	 */
372 	if (poweroff_delay_ms <= 0)
373 		return;
374 	schedule_delayed_work(&thermal_emergency_poweroff_work,
375 			      msecs_to_jiffies(poweroff_delay_ms));
376 }
377 
378 static void handle_critical_trips(struct thermal_zone_device *tz,
379 				  int trip, enum thermal_trip_type trip_type)
380 {
381 	int trip_temp;
382 
383 	tz->ops->get_trip_temp(tz, trip, &trip_temp);
384 
385 	/* If we have not crossed the trip_temp, we do not care. */
386 	if (trip_temp <= 0 || tz->temperature < trip_temp)
387 		return;
388 
389 	trace_thermal_zone_trip(tz, trip, trip_type);
390 
391 	if (tz->ops->notify)
392 		tz->ops->notify(tz, trip, trip_type);
393 
394 	if (trip_type == THERMAL_TRIP_CRITICAL) {
395 		dev_emerg(&tz->device,
396 			  "critical temperature reached (%d C), shutting down\n",
397 			  tz->temperature / 1000);
398 		mutex_lock(&poweroff_lock);
399 		if (!power_off_triggered) {
400 			/*
401 			 * Queue a backup emergency shutdown in the event of
402 			 * orderly_poweroff failure
403 			 */
404 			thermal_emergency_poweroff();
405 			orderly_poweroff(true);
406 			power_off_triggered = true;
407 		}
408 		mutex_unlock(&poweroff_lock);
409 	}
410 }
411 
412 static void handle_thermal_trip(struct thermal_zone_device *tz, int trip)
413 {
414 	enum thermal_trip_type type;
415 
416 	/* Ignore disabled trip points */
417 	if (test_bit(trip, &tz->trips_disabled))
418 		return;
419 
420 	tz->ops->get_trip_type(tz, trip, &type);
421 
422 	if (type == THERMAL_TRIP_CRITICAL || type == THERMAL_TRIP_HOT)
423 		handle_critical_trips(tz, trip, type);
424 	else
425 		handle_non_critical_trips(tz, trip);
426 	/*
427 	 * Alright, we handled this trip successfully.
428 	 * So, start monitoring again.
429 	 */
430 	monitor_thermal_zone(tz);
431 }
432 
433 static void update_temperature(struct thermal_zone_device *tz)
434 {
435 	int temp, ret;
436 
437 	ret = thermal_zone_get_temp(tz, &temp);
438 	if (ret) {
439 		if (ret != -EAGAIN)
440 			dev_warn(&tz->device,
441 				 "failed to read out thermal zone (%d)\n",
442 				 ret);
443 		return;
444 	}
445 
446 	mutex_lock(&tz->lock);
447 	tz->last_temperature = tz->temperature;
448 	tz->temperature = temp;
449 	mutex_unlock(&tz->lock);
450 
451 	trace_thermal_temperature(tz);
452 	if (tz->last_temperature == THERMAL_TEMP_INVALID)
453 		dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n",
454 			tz->temperature);
455 	else
456 		dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
457 			tz->last_temperature, tz->temperature);
458 }
459 
460 static void thermal_zone_device_init(struct thermal_zone_device *tz)
461 {
462 	struct thermal_instance *pos;
463 	tz->temperature = THERMAL_TEMP_INVALID;
464 	list_for_each_entry(pos, &tz->thermal_instances, tz_node)
465 		pos->initialized = false;
466 }
467 
468 static void thermal_zone_device_reset(struct thermal_zone_device *tz)
469 {
470 	tz->passive = 0;
471 	thermal_zone_device_init(tz);
472 }
473 
474 void thermal_zone_device_update(struct thermal_zone_device *tz,
475 				enum thermal_notify_event event)
476 {
477 	int count;
478 
479 	if (atomic_read(&in_suspend))
480 		return;
481 
482 	if (!tz->ops->get_temp)
483 		return;
484 
485 	update_temperature(tz);
486 
487 	thermal_zone_set_trips(tz);
488 
489 	tz->notify_event = event;
490 
491 	for (count = 0; count < tz->trips; count++)
492 		handle_thermal_trip(tz, count);
493 }
494 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
495 
496 /**
497  * thermal_notify_framework - Sensor drivers use this API to notify framework
498  * @tz:		thermal zone device
499  * @trip:	indicates which trip point has been crossed
500  *
501  * This function handles the trip events from sensor drivers. It starts
502  * throttling the cooling devices according to the policy configured.
503  * For CRITICAL and HOT trip points, this notifies the respective drivers,
504  * and does actual throttling for other trip points i.e ACTIVE and PASSIVE.
505  * The throttling policy is based on the configured platform data; if no
506  * platform data is provided, this uses the step_wise throttling policy.
507  */
508 void thermal_notify_framework(struct thermal_zone_device *tz, int trip)
509 {
510 	handle_thermal_trip(tz, trip);
511 }
512 EXPORT_SYMBOL_GPL(thermal_notify_framework);
513 
514 static void thermal_zone_device_check(struct work_struct *work)
515 {
516 	struct thermal_zone_device *tz = container_of(work, struct
517 						      thermal_zone_device,
518 						      poll_queue.work);
519 	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
520 }
521 
522 /*
523  * Power actor section: interface to power actors to estimate power
524  *
525  * Set of functions used to interact to cooling devices that know
526  * how to estimate their devices power consumption.
527  */
528 
529 /**
530  * power_actor_get_max_power() - get the maximum power that a cdev can consume
531  * @cdev:	pointer to &thermal_cooling_device
532  * @tz:		a valid thermal zone device pointer
533  * @max_power:	pointer in which to store the maximum power
534  *
535  * Calculate the maximum power consumption in milliwats that the
536  * cooling device can currently consume and store it in @max_power.
537  *
538  * Return: 0 on success, -EINVAL if @cdev doesn't support the
539  * power_actor API or -E* on other error.
540  */
541 int power_actor_get_max_power(struct thermal_cooling_device *cdev,
542 			      struct thermal_zone_device *tz, u32 *max_power)
543 {
544 	if (!cdev_is_power_actor(cdev))
545 		return -EINVAL;
546 
547 	return cdev->ops->state2power(cdev, tz, 0, max_power);
548 }
549 
550 /**
551  * power_actor_get_min_power() - get the mainimum power that a cdev can consume
552  * @cdev:	pointer to &thermal_cooling_device
553  * @tz:		a valid thermal zone device pointer
554  * @min_power:	pointer in which to store the minimum power
555  *
556  * Calculate the minimum power consumption in milliwatts that the
557  * cooling device can currently consume and store it in @min_power.
558  *
559  * Return: 0 on success, -EINVAL if @cdev doesn't support the
560  * power_actor API or -E* on other error.
561  */
562 int power_actor_get_min_power(struct thermal_cooling_device *cdev,
563 			      struct thermal_zone_device *tz, u32 *min_power)
564 {
565 	unsigned long max_state;
566 	int ret;
567 
568 	if (!cdev_is_power_actor(cdev))
569 		return -EINVAL;
570 
571 	ret = cdev->ops->get_max_state(cdev, &max_state);
572 	if (ret)
573 		return ret;
574 
575 	return cdev->ops->state2power(cdev, tz, max_state, min_power);
576 }
577 
578 /**
579  * power_actor_set_power() - limit the maximum power a cooling device consumes
580  * @cdev:	pointer to &thermal_cooling_device
581  * @instance:	thermal instance to update
582  * @power:	the power in milliwatts
583  *
584  * Set the cooling device to consume at most @power milliwatts. The limit is
585  * expected to be a cap at the maximum power consumption.
586  *
587  * Return: 0 on success, -EINVAL if the cooling device does not
588  * implement the power actor API or -E* for other failures.
589  */
590 int power_actor_set_power(struct thermal_cooling_device *cdev,
591 			  struct thermal_instance *instance, u32 power)
592 {
593 	unsigned long state;
594 	int ret;
595 
596 	if (!cdev_is_power_actor(cdev))
597 		return -EINVAL;
598 
599 	ret = cdev->ops->power2state(cdev, instance->tz, power, &state);
600 	if (ret)
601 		return ret;
602 
603 	instance->target = state;
604 	mutex_lock(&cdev->lock);
605 	cdev->updated = false;
606 	mutex_unlock(&cdev->lock);
607 	thermal_cdev_update(cdev);
608 
609 	return 0;
610 }
611 
612 void thermal_zone_device_rebind_exception(struct thermal_zone_device *tz,
613 					  const char *cdev_type, size_t size)
614 {
615 	struct thermal_cooling_device *cdev = NULL;
616 
617 	mutex_lock(&thermal_list_lock);
618 	list_for_each_entry(cdev, &thermal_cdev_list, node) {
619 		/* skip non matching cdevs */
620 		if (strncmp(cdev_type, cdev->type, size))
621 			continue;
622 
623 		/* re binding the exception matching the type pattern */
624 		thermal_zone_bind_cooling_device(tz, THERMAL_TRIPS_NONE, cdev,
625 						 THERMAL_NO_LIMIT,
626 						 THERMAL_NO_LIMIT,
627 						 THERMAL_WEIGHT_DEFAULT);
628 	}
629 	mutex_unlock(&thermal_list_lock);
630 }
631 
632 void thermal_zone_device_unbind_exception(struct thermal_zone_device *tz,
633 					  const char *cdev_type, size_t size)
634 {
635 	struct thermal_cooling_device *cdev = NULL;
636 
637 	mutex_lock(&thermal_list_lock);
638 	list_for_each_entry(cdev, &thermal_cdev_list, node) {
639 		/* skip non matching cdevs */
640 		if (strncmp(cdev_type, cdev->type, size))
641 			continue;
642 		/* unbinding the exception matching the type pattern */
643 		thermal_zone_unbind_cooling_device(tz, THERMAL_TRIPS_NONE,
644 						   cdev);
645 	}
646 	mutex_unlock(&thermal_list_lock);
647 }
648 
649 /*
650  * Device management section: cooling devices, zones devices, and binding
651  *
652  * Set of functions provided by the thermal core for:
653  * - cooling devices lifecycle: registration, unregistration,
654  *				binding, and unbinding.
655  * - thermal zone devices lifecycle: registration, unregistration,
656  *				     binding, and unbinding.
657  */
658 
659 /**
660  * thermal_zone_bind_cooling_device() - bind a cooling device to a thermal zone
661  * @tz:		pointer to struct thermal_zone_device
662  * @trip:	indicates which trip point the cooling devices is
663  *		associated with in this thermal zone.
664  * @cdev:	pointer to struct thermal_cooling_device
665  * @upper:	the Maximum cooling state for this trip point.
666  *		THERMAL_NO_LIMIT means no upper limit,
667  *		and the cooling device can be in max_state.
668  * @lower:	the Minimum cooling state can be used for this trip point.
669  *		THERMAL_NO_LIMIT means no lower limit,
670  *		and the cooling device can be in cooling state 0.
671  * @weight:	The weight of the cooling device to be bound to the
672  *		thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
673  *		default value
674  *
675  * This interface function bind a thermal cooling device to the certain trip
676  * point of a thermal zone device.
677  * This function is usually called in the thermal zone device .bind callback.
678  *
679  * Return: 0 on success, the proper error value otherwise.
680  */
681 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
682 				     int trip,
683 				     struct thermal_cooling_device *cdev,
684 				     unsigned long upper, unsigned long lower,
685 				     unsigned int weight)
686 {
687 	struct thermal_instance *dev;
688 	struct thermal_instance *pos;
689 	struct thermal_zone_device *pos1;
690 	struct thermal_cooling_device *pos2;
691 	unsigned long max_state;
692 	int result, ret;
693 
694 	if (trip >= tz->trips || (trip < 0 && trip != THERMAL_TRIPS_NONE))
695 		return -EINVAL;
696 
697 	list_for_each_entry(pos1, &thermal_tz_list, node) {
698 		if (pos1 == tz)
699 			break;
700 	}
701 	list_for_each_entry(pos2, &thermal_cdev_list, node) {
702 		if (pos2 == cdev)
703 			break;
704 	}
705 
706 	if (tz != pos1 || cdev != pos2)
707 		return -EINVAL;
708 
709 	ret = cdev->ops->get_max_state(cdev, &max_state);
710 	if (ret)
711 		return ret;
712 
713 	/* lower default 0, upper default max_state */
714 	lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
715 	upper = upper == THERMAL_NO_LIMIT ? max_state : upper;
716 
717 	if (lower > upper || upper > max_state)
718 		return -EINVAL;
719 
720 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
721 	if (!dev)
722 		return -ENOMEM;
723 	dev->tz = tz;
724 	dev->cdev = cdev;
725 	dev->trip = trip;
726 	dev->upper = upper;
727 	dev->lower = lower;
728 	dev->target = THERMAL_NO_TARGET;
729 	dev->weight = weight;
730 
731 	result = ida_simple_get(&tz->ida, 0, 0, GFP_KERNEL);
732 	if (result < 0)
733 		goto free_mem;
734 
735 	dev->id = result;
736 	sprintf(dev->name, "cdev%d", dev->id);
737 	result =
738 	    sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
739 	if (result)
740 		goto release_ida;
741 
742 	sprintf(dev->attr_name, "cdev%d_trip_point", dev->id);
743 	sysfs_attr_init(&dev->attr.attr);
744 	dev->attr.attr.name = dev->attr_name;
745 	dev->attr.attr.mode = 0444;
746 	dev->attr.show = trip_point_show;
747 	result = device_create_file(&tz->device, &dev->attr);
748 	if (result)
749 		goto remove_symbol_link;
750 
751 	sprintf(dev->weight_attr_name, "cdev%d_weight", dev->id);
752 	sysfs_attr_init(&dev->weight_attr.attr);
753 	dev->weight_attr.attr.name = dev->weight_attr_name;
754 	dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
755 	dev->weight_attr.show = weight_show;
756 	dev->weight_attr.store = weight_store;
757 	result = device_create_file(&tz->device, &dev->weight_attr);
758 	if (result)
759 		goto remove_trip_file;
760 
761 	mutex_lock(&tz->lock);
762 	mutex_lock(&cdev->lock);
763 	list_for_each_entry(pos, &tz->thermal_instances, tz_node)
764 		if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
765 			result = -EEXIST;
766 			break;
767 		}
768 	if (!result) {
769 		list_add_tail(&dev->tz_node, &tz->thermal_instances);
770 		list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
771 		atomic_set(&tz->need_update, 1);
772 	}
773 	mutex_unlock(&cdev->lock);
774 	mutex_unlock(&tz->lock);
775 
776 	if (!result)
777 		return 0;
778 
779 	device_remove_file(&tz->device, &dev->weight_attr);
780 remove_trip_file:
781 	device_remove_file(&tz->device, &dev->attr);
782 remove_symbol_link:
783 	sysfs_remove_link(&tz->device.kobj, dev->name);
784 release_ida:
785 	ida_simple_remove(&tz->ida, dev->id);
786 free_mem:
787 	kfree(dev);
788 	return result;
789 }
790 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
791 
792 /**
793  * thermal_zone_unbind_cooling_device() - unbind a cooling device from a
794  *					  thermal zone.
795  * @tz:		pointer to a struct thermal_zone_device.
796  * @trip:	indicates which trip point the cooling devices is
797  *		associated with in this thermal zone.
798  * @cdev:	pointer to a struct thermal_cooling_device.
799  *
800  * This interface function unbind a thermal cooling device from the certain
801  * trip point of a thermal zone device.
802  * This function is usually called in the thermal zone device .unbind callback.
803  *
804  * Return: 0 on success, the proper error value otherwise.
805  */
806 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
807 				       int trip,
808 				       struct thermal_cooling_device *cdev)
809 {
810 	struct thermal_instance *pos, *next;
811 
812 	mutex_lock(&tz->lock);
813 	mutex_lock(&cdev->lock);
814 	list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
815 		if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
816 			list_del(&pos->tz_node);
817 			list_del(&pos->cdev_node);
818 			mutex_unlock(&cdev->lock);
819 			mutex_unlock(&tz->lock);
820 			goto unbind;
821 		}
822 	}
823 	mutex_unlock(&cdev->lock);
824 	mutex_unlock(&tz->lock);
825 
826 	return -ENODEV;
827 
828 unbind:
829 	device_remove_file(&tz->device, &pos->weight_attr);
830 	device_remove_file(&tz->device, &pos->attr);
831 	sysfs_remove_link(&tz->device.kobj, pos->name);
832 	ida_simple_remove(&tz->ida, pos->id);
833 	kfree(pos);
834 	return 0;
835 }
836 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
837 
838 static void thermal_release(struct device *dev)
839 {
840 	struct thermal_zone_device *tz;
841 	struct thermal_cooling_device *cdev;
842 
843 	if (!strncmp(dev_name(dev), "thermal_zone",
844 		     sizeof("thermal_zone") - 1)) {
845 		tz = to_thermal_zone(dev);
846 		thermal_zone_destroy_device_groups(tz);
847 		kfree(tz);
848 	} else if (!strncmp(dev_name(dev), "cooling_device",
849 			    sizeof("cooling_device") - 1)) {
850 		cdev = to_cooling_device(dev);
851 		kfree(cdev);
852 	}
853 }
854 
855 static struct class thermal_class = {
856 	.name = "thermal",
857 	.dev_release = thermal_release,
858 };
859 
860 static inline
861 void print_bind_err_msg(struct thermal_zone_device *tz,
862 			struct thermal_cooling_device *cdev, int ret)
863 {
864 	dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
865 		tz->type, cdev->type, ret);
866 }
867 
868 static void __bind(struct thermal_zone_device *tz, int mask,
869 		   struct thermal_cooling_device *cdev,
870 		   unsigned long *limits,
871 		   unsigned int weight)
872 {
873 	int i, ret;
874 
875 	for (i = 0; i < tz->trips; i++) {
876 		if (mask & (1 << i)) {
877 			unsigned long upper, lower;
878 
879 			upper = THERMAL_NO_LIMIT;
880 			lower = THERMAL_NO_LIMIT;
881 			if (limits) {
882 				lower = limits[i * 2];
883 				upper = limits[i * 2 + 1];
884 			}
885 			ret = thermal_zone_bind_cooling_device(tz, i, cdev,
886 							       upper, lower,
887 							       weight);
888 			if (ret)
889 				print_bind_err_msg(tz, cdev, ret);
890 		}
891 	}
892 }
893 
894 static void bind_cdev(struct thermal_cooling_device *cdev)
895 {
896 	int i, ret;
897 	const struct thermal_zone_params *tzp;
898 	struct thermal_zone_device *pos = NULL;
899 
900 	mutex_lock(&thermal_list_lock);
901 
902 	list_for_each_entry(pos, &thermal_tz_list, node) {
903 		if (!pos->tzp && !pos->ops->bind)
904 			continue;
905 
906 		if (pos->ops->bind) {
907 			ret = pos->ops->bind(pos, cdev);
908 			if (ret)
909 				print_bind_err_msg(pos, cdev, ret);
910 			continue;
911 		}
912 
913 		tzp = pos->tzp;
914 		if (!tzp || !tzp->tbp)
915 			continue;
916 
917 		for (i = 0; i < tzp->num_tbps; i++) {
918 			if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
919 				continue;
920 			if (tzp->tbp[i].match(pos, cdev))
921 				continue;
922 			tzp->tbp[i].cdev = cdev;
923 			__bind(pos, tzp->tbp[i].trip_mask, cdev,
924 			       tzp->tbp[i].binding_limits,
925 			       tzp->tbp[i].weight);
926 		}
927 	}
928 
929 	mutex_unlock(&thermal_list_lock);
930 }
931 
932 /**
933  * __thermal_cooling_device_register() - register a new thermal cooling device
934  * @np:		a pointer to a device tree node.
935  * @type:	the thermal cooling device type.
936  * @devdata:	device private data.
937  * @ops:		standard thermal cooling devices callbacks.
938  *
939  * This interface function adds a new thermal cooling device (fan/processor/...)
940  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
941  * to all the thermal zone devices registered at the same time.
942  * It also gives the opportunity to link the cooling device to a device tree
943  * node, so that it can be bound to a thermal zone created out of device tree.
944  *
945  * Return: a pointer to the created struct thermal_cooling_device or an
946  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
947  */
948 static struct thermal_cooling_device *
949 __thermal_cooling_device_register(struct device_node *np,
950 				  const char *type, void *devdata,
951 				  const struct thermal_cooling_device_ops *ops)
952 {
953 	struct thermal_cooling_device *cdev;
954 	struct thermal_zone_device *pos = NULL;
955 	int result;
956 
957 	if (type && strlen(type) >= THERMAL_NAME_LENGTH)
958 		return ERR_PTR(-EINVAL);
959 
960 	if (!ops || !ops->get_max_state || !ops->get_cur_state ||
961 	    !ops->set_cur_state)
962 		return ERR_PTR(-EINVAL);
963 
964 	cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
965 	if (!cdev)
966 		return ERR_PTR(-ENOMEM);
967 
968 	result = ida_simple_get(&thermal_cdev_ida, 0, 0, GFP_KERNEL);
969 	if (result < 0) {
970 		kfree(cdev);
971 		return ERR_PTR(result);
972 	}
973 
974 	cdev->id = result;
975 	strlcpy(cdev->type, type ? : "", sizeof(cdev->type));
976 	mutex_init(&cdev->lock);
977 	INIT_LIST_HEAD(&cdev->thermal_instances);
978 	cdev->np = np;
979 	cdev->ops = ops;
980 	cdev->updated = false;
981 	cdev->device.class = &thermal_class;
982 	cdev->devdata = devdata;
983 	thermal_cooling_device_setup_sysfs(cdev);
984 	dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
985 	result = device_register(&cdev->device);
986 	if (result) {
987 		ida_simple_remove(&thermal_cdev_ida, cdev->id);
988 		kfree(cdev);
989 		return ERR_PTR(result);
990 	}
991 
992 	/* Add 'this' new cdev to the global cdev list */
993 	mutex_lock(&thermal_list_lock);
994 	list_add(&cdev->node, &thermal_cdev_list);
995 	mutex_unlock(&thermal_list_lock);
996 
997 	/* Update binding information for 'this' new cdev */
998 	bind_cdev(cdev);
999 
1000 	mutex_lock(&thermal_list_lock);
1001 	list_for_each_entry(pos, &thermal_tz_list, node)
1002 		if (atomic_cmpxchg(&pos->need_update, 1, 0))
1003 			thermal_zone_device_update(pos,
1004 						   THERMAL_EVENT_UNSPECIFIED);
1005 	mutex_unlock(&thermal_list_lock);
1006 
1007 	return cdev;
1008 }
1009 
1010 /**
1011  * thermal_cooling_device_register() - register a new thermal cooling device
1012  * @type:	the thermal cooling device type.
1013  * @devdata:	device private data.
1014  * @ops:		standard thermal cooling devices callbacks.
1015  *
1016  * This interface function adds a new thermal cooling device (fan/processor/...)
1017  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1018  * to all the thermal zone devices registered at the same time.
1019  *
1020  * Return: a pointer to the created struct thermal_cooling_device or an
1021  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1022  */
1023 struct thermal_cooling_device *
1024 thermal_cooling_device_register(const char *type, void *devdata,
1025 				const struct thermal_cooling_device_ops *ops)
1026 {
1027 	return __thermal_cooling_device_register(NULL, type, devdata, ops);
1028 }
1029 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1030 
1031 /**
1032  * thermal_of_cooling_device_register() - register an OF thermal cooling device
1033  * @np:		a pointer to a device tree node.
1034  * @type:	the thermal cooling device type.
1035  * @devdata:	device private data.
1036  * @ops:		standard thermal cooling devices callbacks.
1037  *
1038  * This function will register a cooling device with device tree node reference.
1039  * This interface function adds a new thermal cooling device (fan/processor/...)
1040  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1041  * to all the thermal zone devices registered at the same time.
1042  *
1043  * Return: a pointer to the created struct thermal_cooling_device or an
1044  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1045  */
1046 struct thermal_cooling_device *
1047 thermal_of_cooling_device_register(struct device_node *np,
1048 				   const char *type, void *devdata,
1049 				   const struct thermal_cooling_device_ops *ops)
1050 {
1051 	return __thermal_cooling_device_register(np, type, devdata, ops);
1052 }
1053 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1054 
1055 static void thermal_cooling_device_release(struct device *dev, void *res)
1056 {
1057 	thermal_cooling_device_unregister(
1058 				*(struct thermal_cooling_device **)res);
1059 }
1060 
1061 /**
1062  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1063  *					       device
1064  * @dev:	a valid struct device pointer of a sensor device.
1065  * @np:		a pointer to a device tree node.
1066  * @type:	the thermal cooling device type.
1067  * @devdata:	device private data.
1068  * @ops:	standard thermal cooling devices callbacks.
1069  *
1070  * This function will register a cooling device with device tree node reference.
1071  * This interface function adds a new thermal cooling device (fan/processor/...)
1072  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1073  * to all the thermal zone devices registered at the same time.
1074  *
1075  * Return: a pointer to the created struct thermal_cooling_device or an
1076  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1077  */
1078 struct thermal_cooling_device *
1079 devm_thermal_of_cooling_device_register(struct device *dev,
1080 				struct device_node *np,
1081 				char *type, void *devdata,
1082 				const struct thermal_cooling_device_ops *ops)
1083 {
1084 	struct thermal_cooling_device **ptr, *tcd;
1085 
1086 	ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1087 			   GFP_KERNEL);
1088 	if (!ptr)
1089 		return ERR_PTR(-ENOMEM);
1090 
1091 	tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1092 	if (IS_ERR(tcd)) {
1093 		devres_free(ptr);
1094 		return tcd;
1095 	}
1096 
1097 	*ptr = tcd;
1098 	devres_add(dev, ptr);
1099 
1100 	return tcd;
1101 }
1102 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1103 
1104 static void __unbind(struct thermal_zone_device *tz, int mask,
1105 		     struct thermal_cooling_device *cdev)
1106 {
1107 	int i;
1108 
1109 	for (i = 0; i < tz->trips; i++)
1110 		if (mask & (1 << i))
1111 			thermal_zone_unbind_cooling_device(tz, i, cdev);
1112 }
1113 
1114 /**
1115  * thermal_cooling_device_unregister - removes a thermal cooling device
1116  * @cdev:	the thermal cooling device to remove.
1117  *
1118  * thermal_cooling_device_unregister() must be called when a registered
1119  * thermal cooling device is no longer needed.
1120  */
1121 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1122 {
1123 	int i;
1124 	const struct thermal_zone_params *tzp;
1125 	struct thermal_zone_device *tz;
1126 	struct thermal_cooling_device *pos = NULL;
1127 
1128 	if (!cdev)
1129 		return;
1130 
1131 	mutex_lock(&thermal_list_lock);
1132 	list_for_each_entry(pos, &thermal_cdev_list, node)
1133 		if (pos == cdev)
1134 			break;
1135 	if (pos != cdev) {
1136 		/* thermal cooling device not found */
1137 		mutex_unlock(&thermal_list_lock);
1138 		return;
1139 	}
1140 	list_del(&cdev->node);
1141 
1142 	/* Unbind all thermal zones associated with 'this' cdev */
1143 	list_for_each_entry(tz, &thermal_tz_list, node) {
1144 		if (tz->ops->unbind) {
1145 			tz->ops->unbind(tz, cdev);
1146 			continue;
1147 		}
1148 
1149 		if (!tz->tzp || !tz->tzp->tbp)
1150 			continue;
1151 
1152 		tzp = tz->tzp;
1153 		for (i = 0; i < tzp->num_tbps; i++) {
1154 			if (tzp->tbp[i].cdev == cdev) {
1155 				__unbind(tz, tzp->tbp[i].trip_mask, cdev);
1156 				tzp->tbp[i].cdev = NULL;
1157 			}
1158 		}
1159 	}
1160 
1161 	mutex_unlock(&thermal_list_lock);
1162 
1163 	ida_simple_remove(&thermal_cdev_ida, cdev->id);
1164 	device_del(&cdev->device);
1165 	thermal_cooling_device_destroy_sysfs(cdev);
1166 	put_device(&cdev->device);
1167 }
1168 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1169 
1170 static void bind_tz(struct thermal_zone_device *tz)
1171 {
1172 	int i, ret;
1173 	struct thermal_cooling_device *pos = NULL;
1174 	const struct thermal_zone_params *tzp = tz->tzp;
1175 
1176 	if (!tzp && !tz->ops->bind)
1177 		return;
1178 
1179 	mutex_lock(&thermal_list_lock);
1180 
1181 	/* If there is ops->bind, try to use ops->bind */
1182 	if (tz->ops->bind) {
1183 		list_for_each_entry(pos, &thermal_cdev_list, node) {
1184 			ret = tz->ops->bind(tz, pos);
1185 			if (ret)
1186 				print_bind_err_msg(tz, pos, ret);
1187 		}
1188 		goto exit;
1189 	}
1190 
1191 	if (!tzp || !tzp->tbp)
1192 		goto exit;
1193 
1194 	list_for_each_entry(pos, &thermal_cdev_list, node) {
1195 		for (i = 0; i < tzp->num_tbps; i++) {
1196 			if (tzp->tbp[i].cdev || !tzp->tbp[i].match)
1197 				continue;
1198 			if (tzp->tbp[i].match(tz, pos))
1199 				continue;
1200 			tzp->tbp[i].cdev = pos;
1201 			__bind(tz, tzp->tbp[i].trip_mask, pos,
1202 			       tzp->tbp[i].binding_limits,
1203 			       tzp->tbp[i].weight);
1204 		}
1205 	}
1206 exit:
1207 	mutex_unlock(&thermal_list_lock);
1208 }
1209 
1210 /**
1211  * thermal_zone_device_register() - register a new thermal zone device
1212  * @type:	the thermal zone device type
1213  * @trips:	the number of trip points the thermal zone support
1214  * @mask:	a bit string indicating the writeablility of trip points
1215  * @devdata:	private device data
1216  * @ops:	standard thermal zone device callbacks
1217  * @tzp:	thermal zone platform parameters
1218  * @passive_delay: number of milliseconds to wait between polls when
1219  *		   performing passive cooling
1220  * @polling_delay: number of milliseconds to wait between polls when checking
1221  *		   whether trip points have been crossed (0 for interrupt
1222  *		   driven systems)
1223  *
1224  * This interface function adds a new thermal zone device (sensor) to
1225  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1226  * thermal cooling devices registered at the same time.
1227  * thermal_zone_device_unregister() must be called when the device is no
1228  * longer needed. The passive cooling depends on the .get_trend() return value.
1229  *
1230  * Return: a pointer to the created struct thermal_zone_device or an
1231  * in case of error, an ERR_PTR. Caller must check return value with
1232  * IS_ERR*() helpers.
1233  */
1234 struct thermal_zone_device *
1235 thermal_zone_device_register(const char *type, int trips, int mask,
1236 			     void *devdata, struct thermal_zone_device_ops *ops,
1237 			     struct thermal_zone_params *tzp, int passive_delay,
1238 			     int polling_delay)
1239 {
1240 	struct thermal_zone_device *tz;
1241 	enum thermal_trip_type trip_type;
1242 	int trip_temp;
1243 	int result;
1244 	int count;
1245 	struct thermal_governor *governor;
1246 
1247 	if (!type || strlen(type) == 0)
1248 		return ERR_PTR(-EINVAL);
1249 
1250 	if (type && strlen(type) >= THERMAL_NAME_LENGTH)
1251 		return ERR_PTR(-EINVAL);
1252 
1253 	if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips)
1254 		return ERR_PTR(-EINVAL);
1255 
1256 	if (!ops)
1257 		return ERR_PTR(-EINVAL);
1258 
1259 	if (trips > 0 && (!ops->get_trip_type || !ops->get_trip_temp))
1260 		return ERR_PTR(-EINVAL);
1261 
1262 	tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1263 	if (!tz)
1264 		return ERR_PTR(-ENOMEM);
1265 
1266 	INIT_LIST_HEAD(&tz->thermal_instances);
1267 	ida_init(&tz->ida);
1268 	mutex_init(&tz->lock);
1269 	result = ida_simple_get(&thermal_tz_ida, 0, 0, GFP_KERNEL);
1270 	if (result < 0)
1271 		goto free_tz;
1272 
1273 	tz->id = result;
1274 	strlcpy(tz->type, type, sizeof(tz->type));
1275 	tz->ops = ops;
1276 	tz->tzp = tzp;
1277 	tz->device.class = &thermal_class;
1278 	tz->devdata = devdata;
1279 	tz->trips = trips;
1280 	tz->passive_delay = passive_delay;
1281 	tz->polling_delay = polling_delay;
1282 
1283 	/* sys I/F */
1284 	/* Add nodes that are always present via .groups */
1285 	result = thermal_zone_create_device_groups(tz, mask);
1286 	if (result)
1287 		goto remove_id;
1288 
1289 	/* A new thermal zone needs to be updated anyway. */
1290 	atomic_set(&tz->need_update, 1);
1291 
1292 	dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1293 	result = device_register(&tz->device);
1294 	if (result)
1295 		goto remove_device_groups;
1296 
1297 	for (count = 0; count < trips; count++) {
1298 		if (tz->ops->get_trip_type(tz, count, &trip_type))
1299 			set_bit(count, &tz->trips_disabled);
1300 		if (tz->ops->get_trip_temp(tz, count, &trip_temp))
1301 			set_bit(count, &tz->trips_disabled);
1302 		/* Check for bogus trip points */
1303 		if (trip_temp == 0)
1304 			set_bit(count, &tz->trips_disabled);
1305 	}
1306 
1307 	/* Update 'this' zone's governor information */
1308 	mutex_lock(&thermal_governor_lock);
1309 
1310 	if (tz->tzp)
1311 		governor = __find_governor(tz->tzp->governor_name);
1312 	else
1313 		governor = def_governor;
1314 
1315 	result = thermal_set_governor(tz, governor);
1316 	if (result) {
1317 		mutex_unlock(&thermal_governor_lock);
1318 		goto unregister;
1319 	}
1320 
1321 	mutex_unlock(&thermal_governor_lock);
1322 
1323 	if (!tz->tzp || !tz->tzp->no_hwmon) {
1324 		result = thermal_add_hwmon_sysfs(tz);
1325 		if (result)
1326 			goto unregister;
1327 	}
1328 
1329 	mutex_lock(&thermal_list_lock);
1330 	list_add_tail(&tz->node, &thermal_tz_list);
1331 	mutex_unlock(&thermal_list_lock);
1332 
1333 	/* Bind cooling devices for this zone */
1334 	bind_tz(tz);
1335 
1336 	INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1337 
1338 	thermal_zone_device_reset(tz);
1339 	/* Update the new thermal zone and mark it as already updated. */
1340 	if (atomic_cmpxchg(&tz->need_update, 1, 0))
1341 		thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1342 
1343 	return tz;
1344 
1345 unregister:
1346 	ida_simple_remove(&thermal_tz_ida, tz->id);
1347 	device_unregister(&tz->device);
1348 	return ERR_PTR(result);
1349 
1350 remove_device_groups:
1351 	thermal_zone_destroy_device_groups(tz);
1352 remove_id:
1353 	ida_simple_remove(&thermal_tz_ida, tz->id);
1354 free_tz:
1355 	kfree(tz);
1356 	return ERR_PTR(result);
1357 }
1358 EXPORT_SYMBOL_GPL(thermal_zone_device_register);
1359 
1360 /**
1361  * thermal_device_unregister - removes the registered thermal zone device
1362  * @tz: the thermal zone device to remove
1363  */
1364 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1365 {
1366 	int i;
1367 	const struct thermal_zone_params *tzp;
1368 	struct thermal_cooling_device *cdev;
1369 	struct thermal_zone_device *pos = NULL;
1370 
1371 	if (!tz)
1372 		return;
1373 
1374 	tzp = tz->tzp;
1375 
1376 	mutex_lock(&thermal_list_lock);
1377 	list_for_each_entry(pos, &thermal_tz_list, node)
1378 		if (pos == tz)
1379 			break;
1380 	if (pos != tz) {
1381 		/* thermal zone device not found */
1382 		mutex_unlock(&thermal_list_lock);
1383 		return;
1384 	}
1385 	list_del(&tz->node);
1386 
1387 	/* Unbind all cdevs associated with 'this' thermal zone */
1388 	list_for_each_entry(cdev, &thermal_cdev_list, node) {
1389 		if (tz->ops->unbind) {
1390 			tz->ops->unbind(tz, cdev);
1391 			continue;
1392 		}
1393 
1394 		if (!tzp || !tzp->tbp)
1395 			break;
1396 
1397 		for (i = 0; i < tzp->num_tbps; i++) {
1398 			if (tzp->tbp[i].cdev == cdev) {
1399 				__unbind(tz, tzp->tbp[i].trip_mask, cdev);
1400 				tzp->tbp[i].cdev = NULL;
1401 			}
1402 		}
1403 	}
1404 
1405 	mutex_unlock(&thermal_list_lock);
1406 
1407 	thermal_zone_device_set_polling(tz, 0);
1408 
1409 	thermal_set_governor(tz, NULL);
1410 
1411 	thermal_remove_hwmon_sysfs(tz);
1412 	ida_simple_remove(&thermal_tz_ida, tz->id);
1413 	ida_destroy(&tz->ida);
1414 	mutex_destroy(&tz->lock);
1415 	device_unregister(&tz->device);
1416 }
1417 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1418 
1419 /**
1420  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1421  * @name: thermal zone name to fetch the temperature
1422  *
1423  * When only one zone is found with the passed name, returns a reference to it.
1424  *
1425  * Return: On success returns a reference to an unique thermal zone with
1426  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1427  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1428  */
1429 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1430 {
1431 	struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1432 	unsigned int found = 0;
1433 
1434 	if (!name)
1435 		goto exit;
1436 
1437 	mutex_lock(&thermal_list_lock);
1438 	list_for_each_entry(pos, &thermal_tz_list, node)
1439 		if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1440 			found++;
1441 			ref = pos;
1442 		}
1443 	mutex_unlock(&thermal_list_lock);
1444 
1445 	/* nothing has been found, thus an error code for it */
1446 	if (found == 0)
1447 		ref = ERR_PTR(-ENODEV);
1448 	else if (found > 1)
1449 	/* Success only when an unique zone is found */
1450 		ref = ERR_PTR(-EEXIST);
1451 
1452 exit:
1453 	return ref;
1454 }
1455 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1456 
1457 #ifdef CONFIG_NET
1458 static const struct genl_multicast_group thermal_event_mcgrps[] = {
1459 	{ .name = THERMAL_GENL_MCAST_GROUP_NAME, },
1460 };
1461 
1462 static struct genl_family thermal_event_genl_family __ro_after_init = {
1463 	.module = THIS_MODULE,
1464 	.name = THERMAL_GENL_FAMILY_NAME,
1465 	.version = THERMAL_GENL_VERSION,
1466 	.maxattr = THERMAL_GENL_ATTR_MAX,
1467 	.mcgrps = thermal_event_mcgrps,
1468 	.n_mcgrps = ARRAY_SIZE(thermal_event_mcgrps),
1469 };
1470 
1471 int thermal_generate_netlink_event(struct thermal_zone_device *tz,
1472 				   enum events event)
1473 {
1474 	struct sk_buff *skb;
1475 	struct nlattr *attr;
1476 	struct thermal_genl_event *thermal_event;
1477 	void *msg_header;
1478 	int size;
1479 	int result;
1480 	static unsigned int thermal_event_seqnum;
1481 
1482 	if (!tz)
1483 		return -EINVAL;
1484 
1485 	/* allocate memory */
1486 	size = nla_total_size(sizeof(struct thermal_genl_event)) +
1487 	       nla_total_size(0);
1488 
1489 	skb = genlmsg_new(size, GFP_ATOMIC);
1490 	if (!skb)
1491 		return -ENOMEM;
1492 
1493 	/* add the genetlink message header */
1494 	msg_header = genlmsg_put(skb, 0, thermal_event_seqnum++,
1495 				 &thermal_event_genl_family, 0,
1496 				 THERMAL_GENL_CMD_EVENT);
1497 	if (!msg_header) {
1498 		nlmsg_free(skb);
1499 		return -ENOMEM;
1500 	}
1501 
1502 	/* fill the data */
1503 	attr = nla_reserve(skb, THERMAL_GENL_ATTR_EVENT,
1504 			   sizeof(struct thermal_genl_event));
1505 
1506 	if (!attr) {
1507 		nlmsg_free(skb);
1508 		return -EINVAL;
1509 	}
1510 
1511 	thermal_event = nla_data(attr);
1512 	if (!thermal_event) {
1513 		nlmsg_free(skb);
1514 		return -EINVAL;
1515 	}
1516 
1517 	memset(thermal_event, 0, sizeof(struct thermal_genl_event));
1518 
1519 	thermal_event->orig = tz->id;
1520 	thermal_event->event = event;
1521 
1522 	/* send multicast genetlink message */
1523 	genlmsg_end(skb, msg_header);
1524 
1525 	result = genlmsg_multicast(&thermal_event_genl_family, skb, 0,
1526 				   0, GFP_ATOMIC);
1527 	if (result)
1528 		dev_err(&tz->device, "Failed to send netlink event:%d", result);
1529 
1530 	return result;
1531 }
1532 EXPORT_SYMBOL_GPL(thermal_generate_netlink_event);
1533 
1534 static int __init genetlink_init(void)
1535 {
1536 	return genl_register_family(&thermal_event_genl_family);
1537 }
1538 
1539 static void genetlink_exit(void)
1540 {
1541 	genl_unregister_family(&thermal_event_genl_family);
1542 }
1543 #else /* !CONFIG_NET */
1544 static inline int genetlink_init(void) { return 0; }
1545 static inline void genetlink_exit(void) {}
1546 #endif /* !CONFIG_NET */
1547 
1548 static int thermal_pm_notify(struct notifier_block *nb,
1549 			     unsigned long mode, void *_unused)
1550 {
1551 	struct thermal_zone_device *tz;
1552 	enum thermal_device_mode tz_mode;
1553 
1554 	switch (mode) {
1555 	case PM_HIBERNATION_PREPARE:
1556 	case PM_RESTORE_PREPARE:
1557 	case PM_SUSPEND_PREPARE:
1558 		atomic_set(&in_suspend, 1);
1559 		break;
1560 	case PM_POST_HIBERNATION:
1561 	case PM_POST_RESTORE:
1562 	case PM_POST_SUSPEND:
1563 		atomic_set(&in_suspend, 0);
1564 		list_for_each_entry(tz, &thermal_tz_list, node) {
1565 			tz_mode = THERMAL_DEVICE_ENABLED;
1566 			if (tz->ops->get_mode)
1567 				tz->ops->get_mode(tz, &tz_mode);
1568 
1569 			if (tz_mode == THERMAL_DEVICE_DISABLED)
1570 				continue;
1571 
1572 			thermal_zone_device_init(tz);
1573 			thermal_zone_device_update(tz,
1574 						   THERMAL_EVENT_UNSPECIFIED);
1575 		}
1576 		break;
1577 	default:
1578 		break;
1579 	}
1580 	return 0;
1581 }
1582 
1583 static struct notifier_block thermal_pm_nb = {
1584 	.notifier_call = thermal_pm_notify,
1585 };
1586 
1587 static int __init thermal_init(void)
1588 {
1589 	int result;
1590 
1591 	mutex_init(&poweroff_lock);
1592 	result = thermal_register_governors();
1593 	if (result)
1594 		goto error;
1595 
1596 	result = class_register(&thermal_class);
1597 	if (result)
1598 		goto unregister_governors;
1599 
1600 	result = genetlink_init();
1601 	if (result)
1602 		goto unregister_class;
1603 
1604 	result = of_parse_thermal_zones();
1605 	if (result)
1606 		goto exit_netlink;
1607 
1608 	result = register_pm_notifier(&thermal_pm_nb);
1609 	if (result)
1610 		pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1611 			result);
1612 
1613 	return 0;
1614 
1615 exit_netlink:
1616 	genetlink_exit();
1617 unregister_class:
1618 	class_unregister(&thermal_class);
1619 unregister_governors:
1620 	thermal_unregister_governors();
1621 error:
1622 	ida_destroy(&thermal_tz_ida);
1623 	ida_destroy(&thermal_cdev_ida);
1624 	mutex_destroy(&thermal_list_lock);
1625 	mutex_destroy(&thermal_governor_lock);
1626 	mutex_destroy(&poweroff_lock);
1627 	return result;
1628 }
1629 fs_initcall(thermal_init);
1630