xref: /linux-6.15/include/linux/thermal.h (revision daeeb032)
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  * @type: trip point type
65  * @priv: pointer to driver data associated with this trip
66  * @flags: flags representing binary properties of the trip
67  */
68 struct thermal_trip {
69 	int temperature;
70 	int hysteresis;
71 	enum thermal_trip_type type;
72 	u8 flags;
73 	void *priv;
74 };
75 
76 struct thermal_trip_desc {
77 	struct thermal_trip trip;
78 	int threshold;
79 };
80 
81 #define THERMAL_TRIP_FLAG_RW_TEMP	BIT(0)
82 #define THERMAL_TRIP_FLAG_RW_HYST	BIT(1)
83 
84 #define THERMAL_TRIP_FLAG_RW	(THERMAL_TRIP_FLAG_RW_TEMP | \
85 				 THERMAL_TRIP_FLAG_RW_HYST)
86 
87 struct thermal_zone_device_ops {
88 	int (*bind) (struct thermal_zone_device *,
89 		     struct thermal_cooling_device *);
90 	int (*unbind) (struct thermal_zone_device *,
91 		       struct thermal_cooling_device *);
92 	int (*get_temp) (struct thermal_zone_device *, int *);
93 	int (*set_trips) (struct thermal_zone_device *, int, int);
94 	int (*change_mode) (struct thermal_zone_device *,
95 		enum thermal_device_mode);
96 	int (*set_trip_temp) (struct thermal_zone_device *, int, int);
97 	int (*get_crit_temp) (struct thermal_zone_device *, int *);
98 	int (*set_emul_temp) (struct thermal_zone_device *, int);
99 	int (*get_trend) (struct thermal_zone_device *,
100 			  const struct thermal_trip *, enum thermal_trend *);
101 	void (*hot)(struct thermal_zone_device *);
102 	void (*critical)(struct thermal_zone_device *);
103 };
104 
105 struct thermal_cooling_device_ops {
106 	int (*get_max_state) (struct thermal_cooling_device *, unsigned long *);
107 	int (*get_cur_state) (struct thermal_cooling_device *, unsigned long *);
108 	int (*set_cur_state) (struct thermal_cooling_device *, unsigned long);
109 	int (*get_requested_power)(struct thermal_cooling_device *, u32 *);
110 	int (*state2power)(struct thermal_cooling_device *, unsigned long, u32 *);
111 	int (*power2state)(struct thermal_cooling_device *, u32, unsigned long *);
112 };
113 
114 struct thermal_cooling_device {
115 	int id;
116 	const char *type;
117 	unsigned long max_state;
118 	struct device device;
119 	struct device_node *np;
120 	void *devdata;
121 	void *stats;
122 	const struct thermal_cooling_device_ops *ops;
123 	bool updated; /* true if the cooling device does not need update */
124 	struct mutex lock; /* protect thermal_instances list */
125 	struct list_head thermal_instances;
126 	struct list_head node;
127 #ifdef CONFIG_THERMAL_DEBUGFS
128 	struct thermal_debugfs *debugfs;
129 #endif
130 };
131 
132 /**
133  * struct thermal_zone_device - structure for a thermal zone
134  * @id:		unique id number for each thermal zone
135  * @type:	the thermal zone device type
136  * @device:	&struct device for this thermal zone
137  * @removal:	removal completion
138  * @trip_temp_attrs:	attributes for trip points for sysfs: trip temperature
139  * @trip_type_attrs:	attributes for trip points for sysfs: trip type
140  * @trip_hyst_attrs:	attributes for trip points for sysfs: trip hysteresis
141  * @mode:		current mode of this thermal zone
142  * @devdata:	private pointer for device private data
143  * @num_trips:	number of trip points the thermal zone supports
144  * @passive_delay_jiffies: number of jiffies to wait between polls when
145  *			performing passive cooling.
146  * @polling_delay_jiffies: number of jiffies to wait between polls when
147  *			checking whether trip points have been crossed (0 for
148  *			interrupt driven systems)
149  * @temperature:	current temperature.  This is only for core code,
150  *			drivers should use thermal_zone_get_temp() to get the
151  *			current temperature
152  * @last_temperature:	previous temperature read
153  * @emul_temperature:	emulated temperature when using CONFIG_THERMAL_EMULATION
154  * @passive:		1 if you've crossed a passive trip point, 0 otherwise.
155  * @prev_low_trip:	the low current temperature if you've crossed a passive
156 			trip point.
157  * @prev_high_trip:	the above current temperature if you've crossed a
158 			passive trip point.
159  * @need_update:	if equals 1, thermal_zone_device_update needs to be invoked.
160  * @ops:	operations this &thermal_zone_device supports
161  * @tzp:	thermal zone parameters
162  * @governor:	pointer to the governor for this thermal zone
163  * @governor_data:	private pointer for governor data
164  * @thermal_instances:	list of &struct thermal_instance of this thermal zone
165  * @ida:	&struct ida to generate unique id for this zone's cooling
166  *		devices
167  * @lock:	lock to protect thermal_instances list
168  * @node:	node in thermal_tz_list (in thermal_core.c)
169  * @poll_queue:	delayed work for polling
170  * @notify_event: Last notification event
171  * @suspended: thermal zone suspend indicator
172  * @trips:	array of struct thermal_trip objects
173  */
174 struct thermal_zone_device {
175 	int id;
176 	char type[THERMAL_NAME_LENGTH];
177 	struct device device;
178 	struct completion removal;
179 	struct attribute_group trips_attribute_group;
180 	struct thermal_attr *trip_temp_attrs;
181 	struct thermal_attr *trip_type_attrs;
182 	struct thermal_attr *trip_hyst_attrs;
183 	enum thermal_device_mode mode;
184 	void *devdata;
185 	int num_trips;
186 	unsigned long passive_delay_jiffies;
187 	unsigned long polling_delay_jiffies;
188 	int temperature;
189 	int last_temperature;
190 	int emul_temperature;
191 	int passive;
192 	int prev_low_trip;
193 	int prev_high_trip;
194 	atomic_t need_update;
195 	struct thermal_zone_device_ops ops;
196 	struct thermal_zone_params *tzp;
197 	struct thermal_governor *governor;
198 	void *governor_data;
199 	struct list_head thermal_instances;
200 	struct ida ida;
201 	struct mutex lock;
202 	struct list_head node;
203 	struct delayed_work poll_queue;
204 	enum thermal_notify_event notify_event;
205 	bool suspended;
206 #ifdef CONFIG_THERMAL_DEBUGFS
207 	struct thermal_debugfs *debugfs;
208 #endif
209 	struct thermal_trip_desc trips[] __counted_by(num_trips);
210 };
211 
212 /**
213  * struct thermal_governor - structure that holds thermal governor information
214  * @name:	name of the governor
215  * @bind_to_tz: callback called when binding to a thermal zone.  If it
216  *		returns 0, the governor is bound to the thermal zone,
217  *		otherwise it fails.
218  * @unbind_from_tz:	callback called when a governor is unbound from a
219  *			thermal zone.
220  * @throttle:	callback called for every trip point even if temperature is
221  *		below the trip point temperature
222  * @update_tz:	callback called when thermal zone internals have changed, e.g.
223  *		thermal cooling instance was added/removed
224  * @governor_list:	node in thermal_governor_list (in thermal_core.c)
225  */
226 struct thermal_governor {
227 	const char *name;
228 	int (*bind_to_tz)(struct thermal_zone_device *tz);
229 	void (*unbind_from_tz)(struct thermal_zone_device *tz);
230 	int (*throttle)(struct thermal_zone_device *tz,
231 			const struct thermal_trip *trip);
232 	void (*update_tz)(struct thermal_zone_device *tz,
233 			  enum thermal_notify_event reason);
234 	struct list_head	governor_list;
235 };
236 
237 /* Structure to define Thermal Zone parameters */
238 struct thermal_zone_params {
239 	const char *governor_name;
240 
241 	/*
242 	 * a boolean to indicate if the thermal to hwmon sysfs interface
243 	 * is required. when no_hwmon == false, a hwmon sysfs interface
244 	 * will be created. when no_hwmon == true, nothing will be done
245 	 */
246 	bool no_hwmon;
247 
248 	/*
249 	 * Sustainable power (heat) that this thermal zone can dissipate in
250 	 * mW
251 	 */
252 	u32 sustainable_power;
253 
254 	/*
255 	 * Proportional parameter of the PID controller when
256 	 * overshooting (i.e., when temperature is below the target)
257 	 */
258 	s32 k_po;
259 
260 	/*
261 	 * Proportional parameter of the PID controller when
262 	 * undershooting
263 	 */
264 	s32 k_pu;
265 
266 	/* Integral parameter of the PID controller */
267 	s32 k_i;
268 
269 	/* Derivative parameter of the PID controller */
270 	s32 k_d;
271 
272 	/* threshold below which the error is no longer accumulated */
273 	s32 integral_cutoff;
274 
275 	/*
276 	 * @slope:	slope of a linear temperature adjustment curve.
277 	 * 		Used by thermal zone drivers.
278 	 */
279 	int slope;
280 	/*
281 	 * @offset:	offset of a linear temperature adjustment curve.
282 	 * 		Used by thermal zone drivers (default 0).
283 	 */
284 	int offset;
285 };
286 
287 /* Function declarations */
288 #ifdef CONFIG_THERMAL_OF
289 struct thermal_zone_device *devm_thermal_of_zone_register(struct device *dev, int id, void *data,
290 							  const struct thermal_zone_device_ops *ops);
291 
292 void devm_thermal_of_zone_unregister(struct device *dev, struct thermal_zone_device *tz);
293 
294 #else
295 
296 static inline
297 struct thermal_zone_device *devm_thermal_of_zone_register(struct device *dev, int id, void *data,
298 							  const struct thermal_zone_device_ops *ops)
299 {
300 	return ERR_PTR(-ENOTSUPP);
301 }
302 
303 static inline void devm_thermal_of_zone_unregister(struct device *dev,
304 						   struct thermal_zone_device *tz)
305 {
306 }
307 #endif
308 
309 int __thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
310 			    struct thermal_trip *trip);
311 int thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
312 			  struct thermal_trip *trip);
313 int for_each_thermal_trip(struct thermal_zone_device *tz,
314 			  int (*cb)(struct thermal_trip *, void *),
315 			  void *data);
316 int thermal_zone_for_each_trip(struct thermal_zone_device *tz,
317 			       int (*cb)(struct thermal_trip *, void *),
318 			       void *data);
319 int thermal_zone_get_num_trips(struct thermal_zone_device *tz);
320 void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
321 				struct thermal_trip *trip, int temp);
322 
323 int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp);
324 
325 #ifdef CONFIG_THERMAL
326 struct thermal_zone_device *thermal_zone_device_register_with_trips(
327 					const char *type,
328 					const struct thermal_trip *trips,
329 					int num_trips, void *devdata,
330 					const struct thermal_zone_device_ops *ops,
331 					const struct thermal_zone_params *tzp,
332 					int passive_delay, int polling_delay);
333 
334 struct thermal_zone_device *thermal_tripless_zone_device_register(
335 					const char *type,
336 					void *devdata,
337 					const struct thermal_zone_device_ops *ops,
338 					const struct thermal_zone_params *tzp);
339 
340 void thermal_zone_device_unregister(struct thermal_zone_device *tz);
341 
342 void *thermal_zone_device_priv(struct thermal_zone_device *tzd);
343 const char *thermal_zone_device_type(struct thermal_zone_device *tzd);
344 int thermal_zone_device_id(struct thermal_zone_device *tzd);
345 struct device *thermal_zone_device(struct thermal_zone_device *tzd);
346 
347 int thermal_bind_cdev_to_trip(struct thermal_zone_device *tz,
348 			      const struct thermal_trip *trip,
349 			      struct thermal_cooling_device *cdev,
350 			      unsigned long upper, unsigned long lower,
351 			      unsigned int weight);
352 int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
353 				     struct thermal_cooling_device *,
354 				     unsigned long, unsigned long,
355 				     unsigned int);
356 int thermal_unbind_cdev_from_trip(struct thermal_zone_device *tz,
357 				  const struct thermal_trip *trip,
358 				  struct thermal_cooling_device *cdev);
359 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
360 				       struct thermal_cooling_device *);
361 void thermal_zone_device_update(struct thermal_zone_device *,
362 				enum thermal_notify_event);
363 
364 struct thermal_cooling_device *thermal_cooling_device_register(const char *,
365 		void *, const struct thermal_cooling_device_ops *);
366 struct thermal_cooling_device *
367 thermal_of_cooling_device_register(struct device_node *np, const char *, void *,
368 				   const struct thermal_cooling_device_ops *);
369 struct thermal_cooling_device *
370 devm_thermal_of_cooling_device_register(struct device *dev,
371 				struct device_node *np,
372 				char *type, void *devdata,
373 				const struct thermal_cooling_device_ops *ops);
374 void thermal_cooling_device_update(struct thermal_cooling_device *);
375 void thermal_cooling_device_unregister(struct thermal_cooling_device *);
376 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name);
377 int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp);
378 int thermal_zone_get_slope(struct thermal_zone_device *tz);
379 int thermal_zone_get_offset(struct thermal_zone_device *tz);
380 
381 int thermal_zone_device_enable(struct thermal_zone_device *tz);
382 int thermal_zone_device_disable(struct thermal_zone_device *tz);
383 void thermal_zone_device_critical(struct thermal_zone_device *tz);
384 #else
385 static inline struct thermal_zone_device *thermal_zone_device_register_with_trips(
386 					const char *type,
387 					const struct thermal_trip *trips,
388 					int num_trips, void *devdata,
389 					const struct thermal_zone_device_ops *ops,
390 					const struct thermal_zone_params *tzp,
391 					int passive_delay, int polling_delay)
392 { return ERR_PTR(-ENODEV); }
393 
394 static inline struct thermal_zone_device *thermal_tripless_zone_device_register(
395 					const char *type,
396 					void *devdata,
397 					struct thermal_zone_device_ops *ops,
398 					const struct thermal_zone_params *tzp)
399 { return ERR_PTR(-ENODEV); }
400 
401 static inline void thermal_zone_device_unregister(struct thermal_zone_device *tz)
402 { }
403 
404 static inline struct thermal_cooling_device *
405 thermal_cooling_device_register(const char *type, void *devdata,
406 	const struct thermal_cooling_device_ops *ops)
407 { return ERR_PTR(-ENODEV); }
408 static inline struct thermal_cooling_device *
409 thermal_of_cooling_device_register(struct device_node *np,
410 	const char *type, void *devdata,
411 	const struct thermal_cooling_device_ops *ops)
412 { return ERR_PTR(-ENODEV); }
413 static inline struct thermal_cooling_device *
414 devm_thermal_of_cooling_device_register(struct device *dev,
415 				struct device_node *np,
416 				char *type, void *devdata,
417 				const struct thermal_cooling_device_ops *ops)
418 {
419 	return ERR_PTR(-ENODEV);
420 }
421 static inline void thermal_cooling_device_unregister(
422 	struct thermal_cooling_device *cdev)
423 { }
424 static inline struct thermal_zone_device *thermal_zone_get_zone_by_name(
425 		const char *name)
426 { return ERR_PTR(-ENODEV); }
427 static inline int thermal_zone_get_temp(
428 		struct thermal_zone_device *tz, int *temp)
429 { return -ENODEV; }
430 static inline int thermal_zone_get_slope(
431 		struct thermal_zone_device *tz)
432 { return -ENODEV; }
433 static inline int thermal_zone_get_offset(
434 		struct thermal_zone_device *tz)
435 { return -ENODEV; }
436 
437 static inline void *thermal_zone_device_priv(struct thermal_zone_device *tz)
438 {
439 	return NULL;
440 }
441 
442 static inline const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
443 {
444 	return NULL;
445 }
446 
447 static inline int thermal_zone_device_id(struct thermal_zone_device *tzd)
448 {
449 	return -ENODEV;
450 }
451 
452 static inline int thermal_zone_device_enable(struct thermal_zone_device *tz)
453 { return -ENODEV; }
454 
455 static inline int thermal_zone_device_disable(struct thermal_zone_device *tz)
456 { return -ENODEV; }
457 #endif /* CONFIG_THERMAL */
458 
459 #endif /* __THERMAL_H__ */
460