xref: /linux-6.15/include/linux/thermal.h (revision da51bbcd)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  thermal.h  ($Revision: 0 $)
4  *
5  *  Copyright (C) 2008  Intel Corp
6  *  Copyright (C) 2008  Zhang Rui <[email protected]>
7  *  Copyright (C) 2008  Sujith Thomas <[email protected]>
8  */
9 
10 #ifndef __THERMAL_H__
11 #define __THERMAL_H__
12 
13 #include <linux/of.h>
14 #include <linux/idr.h>
15 #include <linux/device.h>
16 #include <linux/sysfs.h>
17 #include <linux/workqueue.h>
18 #include <uapi/linux/thermal.h>
19 
20 /* invalid cooling state */
21 #define THERMAL_CSTATE_INVALID -1UL
22 
23 /* No upper/lower limit requirement */
24 #define THERMAL_NO_LIMIT	((u32)~0)
25 
26 /* Default weight of a bound cooling device */
27 #define THERMAL_WEIGHT_DEFAULT 0
28 
29 /* use value, which < 0K, to indicate an invalid/uninitialized temperature */
30 #define THERMAL_TEMP_INVALID	-274000
31 
32 struct thermal_zone_device;
33 struct thermal_cooling_device;
34 struct thermal_instance;
35 struct thermal_debugfs;
36 struct thermal_attr;
37 
38 enum thermal_trend {
39 	THERMAL_TREND_STABLE, /* temperature is stable */
40 	THERMAL_TREND_RAISING, /* temperature is raising */
41 	THERMAL_TREND_DROPPING, /* temperature is dropping */
42 };
43 
44 /* Thermal notification reason */
45 enum thermal_notify_event {
46 	THERMAL_EVENT_UNSPECIFIED, /* Unspecified event */
47 	THERMAL_EVENT_TEMP_SAMPLE, /* New Temperature sample */
48 	THERMAL_TRIP_VIOLATED, /* TRIP Point violation */
49 	THERMAL_TRIP_CHANGED, /* TRIP Point temperature changed */
50 	THERMAL_DEVICE_DOWN, /* Thermal device is down */
51 	THERMAL_DEVICE_UP, /* Thermal device is up after a down event */
52 	THERMAL_DEVICE_POWER_CAPABILITY_CHANGED, /* power capability changed */
53 	THERMAL_TABLE_CHANGED, /* Thermal table(s) changed */
54 	THERMAL_EVENT_KEEP_ALIVE, /* Request for user space handler to respond */
55 	THERMAL_TZ_BIND_CDEV, /* Cooling dev is bind to the thermal zone */
56 	THERMAL_TZ_UNBIND_CDEV, /* Cooling dev is unbind from the thermal zone */
57 	THERMAL_INSTANCE_WEIGHT_CHANGED, /* Thermal instance weight changed */
58 };
59 
60 /**
61  * struct thermal_trip - representation of a point in temperature domain
62  * @temperature: temperature value in miliCelsius
63  * @hysteresis: relative hysteresis in miliCelsius
64  * @threshold: trip crossing notification threshold miliCelsius
65  * @type: trip point type
66  * @priv: pointer to driver data associated with this trip
67  * @flags: flags representing binary properties of the trip
68  */
69 struct thermal_trip {
70 	int temperature;
71 	int hysteresis;
72 	int threshold;
73 	enum thermal_trip_type type;
74 	u8 flags;
75 	void *priv;
76 };
77 
78 #define THERMAL_TRIP_FLAG_RW_TEMP	BIT(0)
79 #define THERMAL_TRIP_FLAG_RW_HYST	BIT(1)
80 
81 #define THERMAL_TRIP_FLAG_RW	(THERMAL_TRIP_FLAG_RW_TEMP | \
82 				 THERMAL_TRIP_FLAG_RW_HYST)
83 
84 struct thermal_zone_device_ops {
85 	int (*bind) (struct thermal_zone_device *,
86 		     struct thermal_cooling_device *);
87 	int (*unbind) (struct thermal_zone_device *,
88 		       struct thermal_cooling_device *);
89 	int (*get_temp) (struct thermal_zone_device *, int *);
90 	int (*set_trips) (struct thermal_zone_device *, int, int);
91 	int (*change_mode) (struct thermal_zone_device *,
92 		enum thermal_device_mode);
93 	int (*set_trip_temp) (struct thermal_zone_device *, int, int);
94 	int (*get_crit_temp) (struct thermal_zone_device *, int *);
95 	int (*set_emul_temp) (struct thermal_zone_device *, int);
96 	int (*get_trend) (struct thermal_zone_device *,
97 			  const struct thermal_trip *, enum thermal_trend *);
98 	void (*hot)(struct thermal_zone_device *);
99 	void (*critical)(struct thermal_zone_device *);
100 };
101 
102 struct thermal_cooling_device_ops {
103 	int (*get_max_state) (struct thermal_cooling_device *, unsigned long *);
104 	int (*get_cur_state) (struct thermal_cooling_device *, unsigned long *);
105 	int (*set_cur_state) (struct thermal_cooling_device *, unsigned long);
106 	int (*get_requested_power)(struct thermal_cooling_device *, u32 *);
107 	int (*state2power)(struct thermal_cooling_device *, unsigned long, u32 *);
108 	int (*power2state)(struct thermal_cooling_device *, u32, unsigned long *);
109 };
110 
111 struct thermal_cooling_device {
112 	int id;
113 	const char *type;
114 	unsigned long max_state;
115 	struct device device;
116 	struct device_node *np;
117 	void *devdata;
118 	void *stats;
119 	const struct thermal_cooling_device_ops *ops;
120 	bool updated; /* true if the cooling device does not need update */
121 	struct mutex lock; /* protect thermal_instances list */
122 	struct list_head thermal_instances;
123 	struct list_head node;
124 #ifdef CONFIG_THERMAL_DEBUGFS
125 	struct thermal_debugfs *debugfs;
126 #endif
127 };
128 
129 /**
130  * struct thermal_zone_device - structure for a thermal zone
131  * @id:		unique id number for each thermal zone
132  * @type:	the thermal zone device type
133  * @device:	&struct device for this thermal zone
134  * @removal:	removal completion
135  * @trip_temp_attrs:	attributes for trip points for sysfs: trip temperature
136  * @trip_type_attrs:	attributes for trip points for sysfs: trip type
137  * @trip_hyst_attrs:	attributes for trip points for sysfs: trip hysteresis
138  * @mode:		current mode of this thermal zone
139  * @devdata:	private pointer for device private data
140  * @num_trips:	number of trip points the thermal zone supports
141  * @passive_delay_jiffies: number of jiffies to wait between polls when
142  *			performing passive cooling.
143  * @polling_delay_jiffies: number of jiffies to wait between polls when
144  *			checking whether trip points have been crossed (0 for
145  *			interrupt driven systems)
146  * @temperature:	current temperature.  This is only for core code,
147  *			drivers should use thermal_zone_get_temp() to get the
148  *			current temperature
149  * @last_temperature:	previous temperature read
150  * @emul_temperature:	emulated temperature when using CONFIG_THERMAL_EMULATION
151  * @passive:		1 if you've crossed a passive trip point, 0 otherwise.
152  * @prev_low_trip:	the low current temperature if you've crossed a passive
153 			trip point.
154  * @prev_high_trip:	the above current temperature if you've crossed a
155 			passive trip point.
156  * @need_update:	if equals 1, thermal_zone_device_update needs to be invoked.
157  * @ops:	operations this &thermal_zone_device supports
158  * @tzp:	thermal zone parameters
159  * @governor:	pointer to the governor for this thermal zone
160  * @governor_data:	private pointer for governor data
161  * @thermal_instances:	list of &struct thermal_instance of this thermal zone
162  * @ida:	&struct ida to generate unique id for this zone's cooling
163  *		devices
164  * @lock:	lock to protect thermal_instances list
165  * @node:	node in thermal_tz_list (in thermal_core.c)
166  * @poll_queue:	delayed work for polling
167  * @notify_event: Last notification event
168  * @suspended: thermal zone suspend indicator
169  * @trips:	array of struct thermal_trip objects
170  */
171 struct thermal_zone_device {
172 	int id;
173 	char type[THERMAL_NAME_LENGTH];
174 	struct device device;
175 	struct completion removal;
176 	struct attribute_group trips_attribute_group;
177 	struct thermal_attr *trip_temp_attrs;
178 	struct thermal_attr *trip_type_attrs;
179 	struct thermal_attr *trip_hyst_attrs;
180 	enum thermal_device_mode mode;
181 	void *devdata;
182 	int num_trips;
183 	unsigned long passive_delay_jiffies;
184 	unsigned long polling_delay_jiffies;
185 	int temperature;
186 	int last_temperature;
187 	int emul_temperature;
188 	int passive;
189 	int prev_low_trip;
190 	int prev_high_trip;
191 	atomic_t need_update;
192 	struct thermal_zone_device_ops ops;
193 	struct thermal_zone_params *tzp;
194 	struct thermal_governor *governor;
195 	void *governor_data;
196 	struct list_head thermal_instances;
197 	struct ida ida;
198 	struct mutex lock;
199 	struct list_head node;
200 	struct delayed_work poll_queue;
201 	enum thermal_notify_event notify_event;
202 	bool suspended;
203 #ifdef CONFIG_THERMAL_DEBUGFS
204 	struct thermal_debugfs *debugfs;
205 #endif
206 	struct thermal_trip trips[] __counted_by(num_trips);
207 };
208 
209 /**
210  * struct thermal_governor - structure that holds thermal governor information
211  * @name:	name of the governor
212  * @bind_to_tz: callback called when binding to a thermal zone.  If it
213  *		returns 0, the governor is bound to the thermal zone,
214  *		otherwise it fails.
215  * @unbind_from_tz:	callback called when a governor is unbound from a
216  *			thermal zone.
217  * @throttle:	callback called for every trip point even if temperature is
218  *		below the trip point temperature
219  * @update_tz:	callback called when thermal zone internals have changed, e.g.
220  *		thermal cooling instance was added/removed
221  * @governor_list:	node in thermal_governor_list (in thermal_core.c)
222  */
223 struct thermal_governor {
224 	const char *name;
225 	int (*bind_to_tz)(struct thermal_zone_device *tz);
226 	void (*unbind_from_tz)(struct thermal_zone_device *tz);
227 	int (*throttle)(struct thermal_zone_device *tz,
228 			const struct thermal_trip *trip);
229 	void (*update_tz)(struct thermal_zone_device *tz,
230 			  enum thermal_notify_event reason);
231 	struct list_head	governor_list;
232 };
233 
234 /* Structure to define Thermal Zone parameters */
235 struct thermal_zone_params {
236 	const char *governor_name;
237 
238 	/*
239 	 * a boolean to indicate if the thermal to hwmon sysfs interface
240 	 * is required. when no_hwmon == false, a hwmon sysfs interface
241 	 * will be created. when no_hwmon == true, nothing will be done
242 	 */
243 	bool no_hwmon;
244 
245 	/*
246 	 * Sustainable power (heat) that this thermal zone can dissipate in
247 	 * mW
248 	 */
249 	u32 sustainable_power;
250 
251 	/*
252 	 * Proportional parameter of the PID controller when
253 	 * overshooting (i.e., when temperature is below the target)
254 	 */
255 	s32 k_po;
256 
257 	/*
258 	 * Proportional parameter of the PID controller when
259 	 * undershooting
260 	 */
261 	s32 k_pu;
262 
263 	/* Integral parameter of the PID controller */
264 	s32 k_i;
265 
266 	/* Derivative parameter of the PID controller */
267 	s32 k_d;
268 
269 	/* threshold below which the error is no longer accumulated */
270 	s32 integral_cutoff;
271 
272 	/*
273 	 * @slope:	slope of a linear temperature adjustment curve.
274 	 * 		Used by thermal zone drivers.
275 	 */
276 	int slope;
277 	/*
278 	 * @offset:	offset of a linear temperature adjustment curve.
279 	 * 		Used by thermal zone drivers (default 0).
280 	 */
281 	int offset;
282 };
283 
284 /* Function declarations */
285 #ifdef CONFIG_THERMAL_OF
286 struct thermal_zone_device *devm_thermal_of_zone_register(struct device *dev, int id, void *data,
287 							  const struct thermal_zone_device_ops *ops);
288 
289 void devm_thermal_of_zone_unregister(struct device *dev, struct thermal_zone_device *tz);
290 
291 #else
292 
293 static inline
294 struct thermal_zone_device *devm_thermal_of_zone_register(struct device *dev, int id, void *data,
295 							  const struct thermal_zone_device_ops *ops)
296 {
297 	return ERR_PTR(-ENOTSUPP);
298 }
299 
300 static inline void devm_thermal_of_zone_unregister(struct device *dev,
301 						   struct thermal_zone_device *tz)
302 {
303 }
304 #endif
305 
306 int __thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
307 			    struct thermal_trip *trip);
308 int thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
309 			  struct thermal_trip *trip);
310 int for_each_thermal_trip(struct thermal_zone_device *tz,
311 			  int (*cb)(struct thermal_trip *, void *),
312 			  void *data);
313 int thermal_zone_for_each_trip(struct thermal_zone_device *tz,
314 			       int (*cb)(struct thermal_trip *, void *),
315 			       void *data);
316 int thermal_zone_get_num_trips(struct thermal_zone_device *tz);
317 void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
318 				struct thermal_trip *trip, int temp);
319 
320 int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp);
321 
322 #ifdef CONFIG_THERMAL
323 struct thermal_zone_device *thermal_zone_device_register_with_trips(
324 					const char *type,
325 					const struct thermal_trip *trips,
326 					int num_trips, void *devdata,
327 					const struct thermal_zone_device_ops *ops,
328 					const struct thermal_zone_params *tzp,
329 					int passive_delay, int polling_delay);
330 
331 struct thermal_zone_device *thermal_tripless_zone_device_register(
332 					const char *type,
333 					void *devdata,
334 					const struct thermal_zone_device_ops *ops,
335 					const struct thermal_zone_params *tzp);
336 
337 void thermal_zone_device_unregister(struct thermal_zone_device *tz);
338 
339 void *thermal_zone_device_priv(struct thermal_zone_device *tzd);
340 const char *thermal_zone_device_type(struct thermal_zone_device *tzd);
341 int thermal_zone_device_id(struct thermal_zone_device *tzd);
342 struct device *thermal_zone_device(struct thermal_zone_device *tzd);
343 
344 int thermal_bind_cdev_to_trip(struct thermal_zone_device *tz,
345 			      const struct thermal_trip *trip,
346 			      struct thermal_cooling_device *cdev,
347 			      unsigned long upper, unsigned long lower,
348 			      unsigned int weight);
349 int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
350 				     struct thermal_cooling_device *,
351 				     unsigned long, unsigned long,
352 				     unsigned int);
353 int thermal_unbind_cdev_from_trip(struct thermal_zone_device *tz,
354 				  const struct thermal_trip *trip,
355 				  struct thermal_cooling_device *cdev);
356 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
357 				       struct thermal_cooling_device *);
358 void thermal_zone_device_update(struct thermal_zone_device *,
359 				enum thermal_notify_event);
360 
361 struct thermal_cooling_device *thermal_cooling_device_register(const char *,
362 		void *, const struct thermal_cooling_device_ops *);
363 struct thermal_cooling_device *
364 thermal_of_cooling_device_register(struct device_node *np, const char *, void *,
365 				   const struct thermal_cooling_device_ops *);
366 struct thermal_cooling_device *
367 devm_thermal_of_cooling_device_register(struct device *dev,
368 				struct device_node *np,
369 				char *type, void *devdata,
370 				const struct thermal_cooling_device_ops *ops);
371 void thermal_cooling_device_update(struct thermal_cooling_device *);
372 void thermal_cooling_device_unregister(struct thermal_cooling_device *);
373 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name);
374 int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp);
375 int thermal_zone_get_slope(struct thermal_zone_device *tz);
376 int thermal_zone_get_offset(struct thermal_zone_device *tz);
377 
378 int thermal_zone_device_enable(struct thermal_zone_device *tz);
379 int thermal_zone_device_disable(struct thermal_zone_device *tz);
380 void thermal_zone_device_critical(struct thermal_zone_device *tz);
381 #else
382 static inline struct thermal_zone_device *thermal_zone_device_register_with_trips(
383 					const char *type,
384 					const struct thermal_trip *trips,
385 					int num_trips, void *devdata,
386 					const struct thermal_zone_device_ops *ops,
387 					const struct thermal_zone_params *tzp,
388 					int passive_delay, int polling_delay)
389 { return ERR_PTR(-ENODEV); }
390 
391 static inline struct thermal_zone_device *thermal_tripless_zone_device_register(
392 					const char *type,
393 					void *devdata,
394 					struct thermal_zone_device_ops *ops,
395 					const struct thermal_zone_params *tzp)
396 { return ERR_PTR(-ENODEV); }
397 
398 static inline void thermal_zone_device_unregister(struct thermal_zone_device *tz)
399 { }
400 
401 static inline struct thermal_cooling_device *
402 thermal_cooling_device_register(const char *type, void *devdata,
403 	const struct thermal_cooling_device_ops *ops)
404 { return ERR_PTR(-ENODEV); }
405 static inline struct thermal_cooling_device *
406 thermal_of_cooling_device_register(struct device_node *np,
407 	const char *type, void *devdata,
408 	const struct thermal_cooling_device_ops *ops)
409 { return ERR_PTR(-ENODEV); }
410 static inline struct thermal_cooling_device *
411 devm_thermal_of_cooling_device_register(struct device *dev,
412 				struct device_node *np,
413 				char *type, void *devdata,
414 				const struct thermal_cooling_device_ops *ops)
415 {
416 	return ERR_PTR(-ENODEV);
417 }
418 static inline void thermal_cooling_device_unregister(
419 	struct thermal_cooling_device *cdev)
420 { }
421 static inline struct thermal_zone_device *thermal_zone_get_zone_by_name(
422 		const char *name)
423 { return ERR_PTR(-ENODEV); }
424 static inline int thermal_zone_get_temp(
425 		struct thermal_zone_device *tz, int *temp)
426 { return -ENODEV; }
427 static inline int thermal_zone_get_slope(
428 		struct thermal_zone_device *tz)
429 { return -ENODEV; }
430 static inline int thermal_zone_get_offset(
431 		struct thermal_zone_device *tz)
432 { return -ENODEV; }
433 
434 static inline void *thermal_zone_device_priv(struct thermal_zone_device *tz)
435 {
436 	return NULL;
437 }
438 
439 static inline const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
440 {
441 	return NULL;
442 }
443 
444 static inline int thermal_zone_device_id(struct thermal_zone_device *tzd)
445 {
446 	return -ENODEV;
447 }
448 
449 static inline int thermal_zone_device_enable(struct thermal_zone_device *tz)
450 { return -ENODEV; }
451 
452 static inline int thermal_zone_device_disable(struct thermal_zone_device *tz)
453 { return -ENODEV; }
454 #endif /* CONFIG_THERMAL */
455 
456 #endif /* __THERMAL_H__ */
457