xref: /linux-6.15/include/linux/thermal.h (revision acc65769)
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_attr;
36 
37 enum thermal_trend {
38 	THERMAL_TREND_STABLE, /* temperature is stable */
39 	THERMAL_TREND_RAISING, /* temperature is raising */
40 	THERMAL_TREND_DROPPING, /* temperature is dropping */
41 };
42 
43 /* Thermal notification reason */
44 enum thermal_notify_event {
45 	THERMAL_EVENT_UNSPECIFIED, /* Unspecified event */
46 	THERMAL_EVENT_TEMP_SAMPLE, /* New Temperature sample */
47 	THERMAL_TRIP_VIOLATED, /* TRIP Point violation */
48 	THERMAL_TRIP_CHANGED, /* TRIP Point temperature changed */
49 	THERMAL_DEVICE_DOWN, /* Thermal device is down */
50 	THERMAL_DEVICE_UP, /* Thermal device is up after a down event */
51 	THERMAL_DEVICE_POWER_CAPABILITY_CHANGED, /* power capability changed */
52 	THERMAL_TABLE_CHANGED, /* Thermal table(s) changed */
53 	THERMAL_EVENT_KEEP_ALIVE, /* Request for user space handler to respond */
54 	THERMAL_TZ_BIND_CDEV, /* Cooling dev is bind to the thermal zone */
55 	THERMAL_TZ_UNBIND_CDEV, /* Cooling dev is unbind from the thermal zone */
56 	THERMAL_INSTANCE_WEIGHT_CHANGED, /* Thermal instance weight changed */
57 };
58 
59 /**
60  * struct thermal_trip - representation of a point in temperature domain
61  * @temperature: temperature value in miliCelsius
62  * @hysteresis: relative hysteresis in miliCelsius
63  * @threshold: trip crossing notification threshold miliCelsius
64  * @type: trip point type
65  * @priv: pointer to driver data associated with this trip
66  */
67 struct thermal_trip {
68 	int temperature;
69 	int hysteresis;
70 	int threshold;
71 	enum thermal_trip_type type;
72 	void *priv;
73 };
74 
75 struct thermal_zone_device_ops {
76 	int (*bind) (struct thermal_zone_device *,
77 		     struct thermal_cooling_device *);
78 	int (*unbind) (struct thermal_zone_device *,
79 		       struct thermal_cooling_device *);
80 	int (*get_temp) (struct thermal_zone_device *, int *);
81 	int (*set_trips) (struct thermal_zone_device *, int, int);
82 	int (*change_mode) (struct thermal_zone_device *,
83 		enum thermal_device_mode);
84 	int (*set_trip_temp) (struct thermal_zone_device *, int, int);
85 	int (*set_trip_hyst) (struct thermal_zone_device *, int, int);
86 	int (*get_crit_temp) (struct thermal_zone_device *, int *);
87 	int (*set_emul_temp) (struct thermal_zone_device *, int);
88 	int (*get_trend) (struct thermal_zone_device *,
89 			  const struct thermal_trip *, enum thermal_trend *);
90 	void (*hot)(struct thermal_zone_device *);
91 	void (*critical)(struct thermal_zone_device *);
92 };
93 
94 struct thermal_cooling_device_ops {
95 	int (*get_max_state) (struct thermal_cooling_device *, unsigned long *);
96 	int (*get_cur_state) (struct thermal_cooling_device *, unsigned long *);
97 	int (*set_cur_state) (struct thermal_cooling_device *, unsigned long);
98 	int (*get_requested_power)(struct thermal_cooling_device *, u32 *);
99 	int (*state2power)(struct thermal_cooling_device *, unsigned long, u32 *);
100 	int (*power2state)(struct thermal_cooling_device *, u32, unsigned long *);
101 };
102 
103 struct thermal_cooling_device {
104 	int id;
105 	char *type;
106 	unsigned long max_state;
107 	struct device device;
108 	struct device_node *np;
109 	void *devdata;
110 	void *stats;
111 	const struct thermal_cooling_device_ops *ops;
112 	bool updated; /* true if the cooling device does not need update */
113 	struct mutex lock; /* protect thermal_instances list */
114 	struct list_head thermal_instances;
115 	struct list_head node;
116 };
117 
118 /**
119  * struct thermal_zone_device - structure for a thermal zone
120  * @id:		unique id number for each thermal zone
121  * @type:	the thermal zone device type
122  * @device:	&struct device for this thermal zone
123  * @removal:	removal completion
124  * @trip_temp_attrs:	attributes for trip points for sysfs: trip temperature
125  * @trip_type_attrs:	attributes for trip points for sysfs: trip type
126  * @trip_hyst_attrs:	attributes for trip points for sysfs: trip hysteresis
127  * @mode:		current mode of this thermal zone
128  * @devdata:	private pointer for device private data
129  * @trips:	an array of struct thermal_trip
130  * @num_trips:	number of trip points the thermal zone supports
131  * @passive_delay_jiffies: number of jiffies to wait between polls when
132  *			performing passive cooling.
133  * @polling_delay_jiffies: number of jiffies to wait between polls when
134  *			checking whether trip points have been crossed (0 for
135  *			interrupt driven systems)
136  * @temperature:	current temperature.  This is only for core code,
137  *			drivers should use thermal_zone_get_temp() to get the
138  *			current temperature
139  * @last_temperature:	previous temperature read
140  * @emul_temperature:	emulated temperature when using CONFIG_THERMAL_EMULATION
141  * @passive:		1 if you've crossed a passive trip point, 0 otherwise.
142  * @prev_low_trip:	the low current temperature if you've crossed a passive
143 			trip point.
144  * @prev_high_trip:	the above current temperature if you've crossed a
145 			passive trip point.
146  * @need_update:	if equals 1, thermal_zone_device_update needs to be invoked.
147  * @ops:	operations this &thermal_zone_device supports
148  * @tzp:	thermal zone parameters
149  * @governor:	pointer to the governor for this thermal zone
150  * @governor_data:	private pointer for governor data
151  * @thermal_instances:	list of &struct thermal_instance of this thermal zone
152  * @ida:	&struct ida to generate unique id for this zone's cooling
153  *		devices
154  * @lock:	lock to protect thermal_instances list
155  * @node:	node in thermal_tz_list (in thermal_core.c)
156  * @poll_queue:	delayed work for polling
157  * @notify_event: Last notification event
158  * @suspended: thermal zone suspend indicator
159  */
160 struct thermal_zone_device {
161 	int id;
162 	char type[THERMAL_NAME_LENGTH];
163 	struct device device;
164 	struct completion removal;
165 	struct attribute_group trips_attribute_group;
166 	struct thermal_attr *trip_temp_attrs;
167 	struct thermal_attr *trip_type_attrs;
168 	struct thermal_attr *trip_hyst_attrs;
169 	enum thermal_device_mode mode;
170 	void *devdata;
171 	struct thermal_trip *trips;
172 	int num_trips;
173 	unsigned long passive_delay_jiffies;
174 	unsigned long polling_delay_jiffies;
175 	int temperature;
176 	int last_temperature;
177 	int emul_temperature;
178 	int passive;
179 	int prev_low_trip;
180 	int prev_high_trip;
181 	atomic_t need_update;
182 	struct thermal_zone_device_ops *ops;
183 	struct thermal_zone_params *tzp;
184 	struct thermal_governor *governor;
185 	void *governor_data;
186 	struct list_head thermal_instances;
187 	struct ida ida;
188 	struct mutex lock;
189 	struct list_head node;
190 	struct delayed_work poll_queue;
191 	enum thermal_notify_event notify_event;
192 	bool suspended;
193 };
194 
195 /**
196  * struct thermal_governor - structure that holds thermal governor information
197  * @name:	name of the governor
198  * @bind_to_tz: callback called when binding to a thermal zone.  If it
199  *		returns 0, the governor is bound to the thermal zone,
200  *		otherwise it fails.
201  * @unbind_from_tz:	callback called when a governor is unbound from a
202  *			thermal zone.
203  * @throttle:	callback called for every trip point even if temperature is
204  *		below the trip point temperature
205  * @update_tz:	callback called when thermal zone internals have changed, e.g.
206  *		thermal cooling instance was added/removed
207  * @governor_list:	node in thermal_governor_list (in thermal_core.c)
208  */
209 struct thermal_governor {
210 	char name[THERMAL_NAME_LENGTH];
211 	int (*bind_to_tz)(struct thermal_zone_device *tz);
212 	void (*unbind_from_tz)(struct thermal_zone_device *tz);
213 	int (*throttle)(struct thermal_zone_device *tz,
214 			const struct thermal_trip *trip);
215 	void (*update_tz)(struct thermal_zone_device *tz,
216 			  enum thermal_notify_event reason);
217 	struct list_head	governor_list;
218 };
219 
220 /* Structure to define Thermal Zone parameters */
221 struct thermal_zone_params {
222 	char governor_name[THERMAL_NAME_LENGTH];
223 
224 	/*
225 	 * a boolean to indicate if the thermal to hwmon sysfs interface
226 	 * is required. when no_hwmon == false, a hwmon sysfs interface
227 	 * will be created. when no_hwmon == true, nothing will be done
228 	 */
229 	bool no_hwmon;
230 
231 	/*
232 	 * Sustainable power (heat) that this thermal zone can dissipate in
233 	 * mW
234 	 */
235 	u32 sustainable_power;
236 
237 	/*
238 	 * Proportional parameter of the PID controller when
239 	 * overshooting (i.e., when temperature is below the target)
240 	 */
241 	s32 k_po;
242 
243 	/*
244 	 * Proportional parameter of the PID controller when
245 	 * undershooting
246 	 */
247 	s32 k_pu;
248 
249 	/* Integral parameter of the PID controller */
250 	s32 k_i;
251 
252 	/* Derivative parameter of the PID controller */
253 	s32 k_d;
254 
255 	/* threshold below which the error is no longer accumulated */
256 	s32 integral_cutoff;
257 
258 	/*
259 	 * @slope:	slope of a linear temperature adjustment curve.
260 	 * 		Used by thermal zone drivers.
261 	 */
262 	int slope;
263 	/*
264 	 * @offset:	offset of a linear temperature adjustment curve.
265 	 * 		Used by thermal zone drivers (default 0).
266 	 */
267 	int offset;
268 };
269 
270 /* Function declarations */
271 #ifdef CONFIG_THERMAL_OF
272 struct thermal_zone_device *devm_thermal_of_zone_register(struct device *dev, int id, void *data,
273 							  const struct thermal_zone_device_ops *ops);
274 
275 void devm_thermal_of_zone_unregister(struct device *dev, struct thermal_zone_device *tz);
276 
277 #else
278 
279 static inline
280 struct thermal_zone_device *devm_thermal_of_zone_register(struct device *dev, int id, void *data,
281 							  const struct thermal_zone_device_ops *ops)
282 {
283 	return ERR_PTR(-ENOTSUPP);
284 }
285 
286 static inline void devm_thermal_of_zone_unregister(struct device *dev,
287 						   struct thermal_zone_device *tz)
288 {
289 }
290 #endif
291 
292 int __thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
293 			    struct thermal_trip *trip);
294 int thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
295 			  struct thermal_trip *trip);
296 int for_each_thermal_trip(struct thermal_zone_device *tz,
297 			  int (*cb)(struct thermal_trip *, void *),
298 			  void *data);
299 int thermal_zone_for_each_trip(struct thermal_zone_device *tz,
300 			       int (*cb)(struct thermal_trip *, void *),
301 			       void *data);
302 int thermal_zone_get_num_trips(struct thermal_zone_device *tz);
303 void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
304 				struct thermal_trip *trip, int temp);
305 
306 int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp);
307 
308 #ifdef CONFIG_THERMAL
309 struct thermal_zone_device *thermal_zone_device_register_with_trips(
310 					const char *type,
311 					struct thermal_trip *trips,
312 					int num_trips, int mask,
313 					void *devdata,
314 					struct thermal_zone_device_ops *ops,
315 					const struct thermal_zone_params *tzp,
316 					int passive_delay, int polling_delay);
317 
318 struct thermal_zone_device *thermal_tripless_zone_device_register(
319 					const char *type,
320 					void *devdata,
321 					struct thermal_zone_device_ops *ops,
322 					const struct thermal_zone_params *tzp);
323 
324 void thermal_zone_device_unregister(struct thermal_zone_device *tz);
325 
326 void *thermal_zone_device_priv(struct thermal_zone_device *tzd);
327 const char *thermal_zone_device_type(struct thermal_zone_device *tzd);
328 int thermal_zone_device_id(struct thermal_zone_device *tzd);
329 struct device *thermal_zone_device(struct thermal_zone_device *tzd);
330 
331 int thermal_bind_cdev_to_trip(struct thermal_zone_device *tz,
332 			      const struct thermal_trip *trip,
333 			      struct thermal_cooling_device *cdev,
334 			      unsigned long upper, unsigned long lower,
335 			      unsigned int weight);
336 int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
337 				     struct thermal_cooling_device *,
338 				     unsigned long, unsigned long,
339 				     unsigned int);
340 int thermal_unbind_cdev_from_trip(struct thermal_zone_device *tz,
341 				  const struct thermal_trip *trip,
342 				  struct thermal_cooling_device *cdev);
343 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
344 				       struct thermal_cooling_device *);
345 void thermal_zone_device_update(struct thermal_zone_device *,
346 				enum thermal_notify_event);
347 
348 struct thermal_cooling_device *thermal_cooling_device_register(const char *,
349 		void *, const struct thermal_cooling_device_ops *);
350 struct thermal_cooling_device *
351 thermal_of_cooling_device_register(struct device_node *np, const char *, void *,
352 				   const struct thermal_cooling_device_ops *);
353 struct thermal_cooling_device *
354 devm_thermal_of_cooling_device_register(struct device *dev,
355 				struct device_node *np,
356 				char *type, void *devdata,
357 				const struct thermal_cooling_device_ops *ops);
358 void thermal_cooling_device_update(struct thermal_cooling_device *);
359 void thermal_cooling_device_unregister(struct thermal_cooling_device *);
360 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name);
361 int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp);
362 int thermal_zone_get_slope(struct thermal_zone_device *tz);
363 int thermal_zone_get_offset(struct thermal_zone_device *tz);
364 
365 int thermal_zone_device_enable(struct thermal_zone_device *tz);
366 int thermal_zone_device_disable(struct thermal_zone_device *tz);
367 void thermal_zone_device_critical(struct thermal_zone_device *tz);
368 #else
369 static inline struct thermal_zone_device *thermal_zone_device_register_with_trips(
370 					const char *type,
371 					struct thermal_trip *trips,
372 					int num_trips, int mask,
373 					void *devdata,
374 					struct thermal_zone_device_ops *ops,
375 					const struct thermal_zone_params *tzp,
376 					int passive_delay, int polling_delay)
377 { return ERR_PTR(-ENODEV); }
378 
379 static inline struct thermal_zone_device *thermal_tripless_zone_device_register(
380 					const char *type,
381 					void *devdata,
382 					struct thermal_zone_device_ops *ops,
383 					const struct thermal_zone_params *tzp)
384 { return ERR_PTR(-ENODEV); }
385 
386 static inline void thermal_zone_device_unregister(struct thermal_zone_device *tz)
387 { }
388 
389 static inline struct thermal_cooling_device *
390 thermal_cooling_device_register(const char *type, void *devdata,
391 	const struct thermal_cooling_device_ops *ops)
392 { return ERR_PTR(-ENODEV); }
393 static inline struct thermal_cooling_device *
394 thermal_of_cooling_device_register(struct device_node *np,
395 	const char *type, void *devdata,
396 	const struct thermal_cooling_device_ops *ops)
397 { return ERR_PTR(-ENODEV); }
398 static inline struct thermal_cooling_device *
399 devm_thermal_of_cooling_device_register(struct device *dev,
400 				struct device_node *np,
401 				char *type, void *devdata,
402 				const struct thermal_cooling_device_ops *ops)
403 {
404 	return ERR_PTR(-ENODEV);
405 }
406 static inline void thermal_cooling_device_unregister(
407 	struct thermal_cooling_device *cdev)
408 { }
409 static inline struct thermal_zone_device *thermal_zone_get_zone_by_name(
410 		const char *name)
411 { return ERR_PTR(-ENODEV); }
412 static inline int thermal_zone_get_temp(
413 		struct thermal_zone_device *tz, int *temp)
414 { return -ENODEV; }
415 static inline int thermal_zone_get_slope(
416 		struct thermal_zone_device *tz)
417 { return -ENODEV; }
418 static inline int thermal_zone_get_offset(
419 		struct thermal_zone_device *tz)
420 { return -ENODEV; }
421 
422 static inline void *thermal_zone_device_priv(struct thermal_zone_device *tz)
423 {
424 	return NULL;
425 }
426 
427 static inline const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
428 {
429 	return NULL;
430 }
431 
432 static inline int thermal_zone_device_id(struct thermal_zone_device *tzd)
433 {
434 	return -ENODEV;
435 }
436 
437 static inline int thermal_zone_device_enable(struct thermal_zone_device *tz)
438 { return -ENODEV; }
439 
440 static inline int thermal_zone_device_disable(struct thermal_zone_device *tz)
441 { return -ENODEV; }
442 #endif /* CONFIG_THERMAL */
443 
444 #endif /* __THERMAL_H__ */
445