xref: /linux-6.15/include/linux/thermal.h (revision f96cffd7)
1 /*
2  *  thermal.h  ($Revision: 0 $)
3  *
4  *  Copyright (C) 2008  Intel Corp
5  *  Copyright (C) 2008  Zhang Rui <[email protected]>
6  *  Copyright (C) 2008  Sujith Thomas <[email protected]>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; version 2 of the License.
12  *
13  *  This program is distributed in the hope that it will be useful, but
14  *  WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  *  General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License along
19  *  with this program; if not, write to the Free Software Foundation, Inc.,
20  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
21  *
22  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23  */
24 
25 #ifndef __THERMAL_H__
26 #define __THERMAL_H__
27 
28 #include <linux/of.h>
29 #include <linux/idr.h>
30 #include <linux/device.h>
31 #include <linux/workqueue.h>
32 #include <uapi/linux/thermal.h>
33 
34 #define THERMAL_TRIPS_NONE	-1
35 #define THERMAL_MAX_TRIPS	12
36 
37 /* invalid cooling state */
38 #define THERMAL_CSTATE_INVALID -1UL
39 
40 /* No upper/lower limit requirement */
41 #define THERMAL_NO_LIMIT	((u32)~0)
42 
43 /* Default weight of a bound cooling device */
44 #define THERMAL_WEIGHT_DEFAULT 0
45 
46 /* use value, which < 0K, to indicate an invalid/uninitialized temperature */
47 #define THERMAL_TEMP_INVALID	-274000
48 
49 /* Unit conversion macros */
50 #define DECI_KELVIN_TO_CELSIUS(t)	({			\
51 	long _t = (t);						\
52 	((_t-2732 >= 0) ? (_t-2732+5)/10 : (_t-2732-5)/10);	\
53 })
54 #define CELSIUS_TO_DECI_KELVIN(t)	((t)*10+2732)
55 #define DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(t, off) (((t) - (off)) * 100)
56 #define DECI_KELVIN_TO_MILLICELSIUS(t) DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(t, 2732)
57 #define MILLICELSIUS_TO_DECI_KELVIN_WITH_OFFSET(t, off) (((t) / 100) + (off))
58 #define MILLICELSIUS_TO_DECI_KELVIN(t) MILLICELSIUS_TO_DECI_KELVIN_WITH_OFFSET(t, 2732)
59 
60 /* Default Thermal Governor */
61 #if defined(CONFIG_THERMAL_DEFAULT_GOV_STEP_WISE)
62 #define DEFAULT_THERMAL_GOVERNOR       "step_wise"
63 #elif defined(CONFIG_THERMAL_DEFAULT_GOV_FAIR_SHARE)
64 #define DEFAULT_THERMAL_GOVERNOR       "fair_share"
65 #elif defined(CONFIG_THERMAL_DEFAULT_GOV_USER_SPACE)
66 #define DEFAULT_THERMAL_GOVERNOR       "user_space"
67 #elif defined(CONFIG_THERMAL_DEFAULT_GOV_POWER_ALLOCATOR)
68 #define DEFAULT_THERMAL_GOVERNOR       "power_allocator"
69 #endif
70 
71 struct thermal_zone_device;
72 struct thermal_cooling_device;
73 struct thermal_instance;
74 
75 enum thermal_device_mode {
76 	THERMAL_DEVICE_DISABLED = 0,
77 	THERMAL_DEVICE_ENABLED,
78 };
79 
80 enum thermal_trip_type {
81 	THERMAL_TRIP_ACTIVE = 0,
82 	THERMAL_TRIP_PASSIVE,
83 	THERMAL_TRIP_HOT,
84 	THERMAL_TRIP_CRITICAL,
85 };
86 
87 enum thermal_trend {
88 	THERMAL_TREND_STABLE, /* temperature is stable */
89 	THERMAL_TREND_RAISING, /* temperature is raising */
90 	THERMAL_TREND_DROPPING, /* temperature is dropping */
91 	THERMAL_TREND_RAISE_FULL, /* apply highest cooling action */
92 	THERMAL_TREND_DROP_FULL, /* apply lowest cooling action */
93 };
94 
95 /* Thermal notification reason */
96 enum thermal_notify_event {
97 	THERMAL_EVENT_UNSPECIFIED, /* Unspecified event */
98 	THERMAL_EVENT_TEMP_SAMPLE, /* New Temperature sample */
99 	THERMAL_TRIP_VIOLATED, /* TRIP Point violation */
100 	THERMAL_TRIP_CHANGED, /* TRIP Point temperature changed */
101 	THERMAL_DEVICE_DOWN, /* Thermal device is down */
102 	THERMAL_DEVICE_UP, /* Thermal device is up after a down event */
103 	THERMAL_DEVICE_POWER_CAPABILITY_CHANGED, /* power capability changed */
104 };
105 
106 struct thermal_zone_device_ops {
107 	int (*bind) (struct thermal_zone_device *,
108 		     struct thermal_cooling_device *);
109 	int (*unbind) (struct thermal_zone_device *,
110 		       struct thermal_cooling_device *);
111 	int (*get_temp) (struct thermal_zone_device *, int *);
112 	int (*set_trips) (struct thermal_zone_device *, int, int);
113 	int (*get_mode) (struct thermal_zone_device *,
114 			 enum thermal_device_mode *);
115 	int (*set_mode) (struct thermal_zone_device *,
116 		enum thermal_device_mode);
117 	int (*get_trip_type) (struct thermal_zone_device *, int,
118 		enum thermal_trip_type *);
119 	int (*get_trip_temp) (struct thermal_zone_device *, int, int *);
120 	int (*set_trip_temp) (struct thermal_zone_device *, int, int);
121 	int (*get_trip_hyst) (struct thermal_zone_device *, int, int *);
122 	int (*set_trip_hyst) (struct thermal_zone_device *, int, int);
123 	int (*get_crit_temp) (struct thermal_zone_device *, int *);
124 	int (*set_emul_temp) (struct thermal_zone_device *, int);
125 	int (*get_trend) (struct thermal_zone_device *, int,
126 			  enum thermal_trend *);
127 	int (*notify) (struct thermal_zone_device *, int,
128 		       enum thermal_trip_type);
129 };
130 
131 struct thermal_cooling_device_ops {
132 	int (*get_max_state) (struct thermal_cooling_device *, unsigned long *);
133 	int (*get_cur_state) (struct thermal_cooling_device *, unsigned long *);
134 	int (*set_cur_state) (struct thermal_cooling_device *, unsigned long);
135 	int (*get_requested_power)(struct thermal_cooling_device *,
136 				   struct thermal_zone_device *, u32 *);
137 	int (*state2power)(struct thermal_cooling_device *,
138 			   struct thermal_zone_device *, unsigned long, u32 *);
139 	int (*power2state)(struct thermal_cooling_device *,
140 			   struct thermal_zone_device *, u32, unsigned long *);
141 };
142 
143 struct thermal_cooling_device {
144 	int id;
145 	char type[THERMAL_NAME_LENGTH];
146 	struct device device;
147 	struct device_node *np;
148 	void *devdata;
149 	const struct thermal_cooling_device_ops *ops;
150 	bool updated; /* true if the cooling device does not need update */
151 	struct mutex lock; /* protect thermal_instances list */
152 	struct list_head thermal_instances;
153 	struct list_head node;
154 };
155 
156 struct thermal_attr {
157 	struct device_attribute attr;
158 	char name[THERMAL_NAME_LENGTH];
159 };
160 
161 /**
162  * struct thermal_zone_device - structure for a thermal zone
163  * @id:		unique id number for each thermal zone
164  * @type:	the thermal zone device type
165  * @device:	&struct device for this thermal zone
166  * @trip_temp_attrs:	attributes for trip points for sysfs: trip temperature
167  * @trip_type_attrs:	attributes for trip points for sysfs: trip type
168  * @trip_hyst_attrs:	attributes for trip points for sysfs: trip hysteresis
169  * @devdata:	private pointer for device private data
170  * @trips:	number of trip points the thermal zone supports
171  * @trips_disabled;	bitmap for disabled trips
172  * @passive_delay:	number of milliseconds to wait between polls when
173  *			performing passive cooling.
174  * @polling_delay:	number of milliseconds to wait between polls when
175  *			checking whether trip points have been crossed (0 for
176  *			interrupt driven systems)
177  * @temperature:	current temperature.  This is only for core code,
178  *			drivers should use thermal_zone_get_temp() to get the
179  *			current temperature
180  * @last_temperature:	previous temperature read
181  * @emul_temperature:	emulated temperature when using CONFIG_THERMAL_EMULATION
182  * @passive:		1 if you've crossed a passive trip point, 0 otherwise.
183  * @prev_low_trip:	the low current temperature if you've crossed a passive
184 			trip point.
185  * @prev_high_trip:	the above current temperature if you've crossed a
186 			passive trip point.
187  * @forced_passive:	If > 0, temperature at which to switch on all ACPI
188  *			processor cooling devices.  Currently only used by the
189  *			step-wise governor.
190  * @need_update:	if equals 1, thermal_zone_device_update needs to be invoked.
191  * @ops:	operations this &thermal_zone_device supports
192  * @tzp:	thermal zone parameters
193  * @governor:	pointer to the governor for this thermal zone
194  * @governor_data:	private pointer for governor data
195  * @thermal_instances:	list of &struct thermal_instance of this thermal zone
196  * @idr:	&struct idr to generate unique id for this zone's cooling
197  *		devices
198  * @lock:	lock to protect thermal_instances list
199  * @node:	node in thermal_tz_list (in thermal_core.c)
200  * @poll_queue:	delayed work for polling
201  * @notify_event: Last notification event
202  */
203 struct thermal_zone_device {
204 	int id;
205 	char type[THERMAL_NAME_LENGTH];
206 	struct device device;
207 	struct thermal_attr *trip_temp_attrs;
208 	struct thermal_attr *trip_type_attrs;
209 	struct thermal_attr *trip_hyst_attrs;
210 	void *devdata;
211 	int trips;
212 	unsigned long trips_disabled;	/* bitmap for disabled trips */
213 	int passive_delay;
214 	int polling_delay;
215 	int temperature;
216 	int last_temperature;
217 	int emul_temperature;
218 	int passive;
219 	int prev_low_trip;
220 	int prev_high_trip;
221 	unsigned int forced_passive;
222 	atomic_t need_update;
223 	struct thermal_zone_device_ops *ops;
224 	struct thermal_zone_params *tzp;
225 	struct thermal_governor *governor;
226 	void *governor_data;
227 	struct list_head thermal_instances;
228 	struct idr idr;
229 	struct mutex lock;
230 	struct list_head node;
231 	struct delayed_work poll_queue;
232 	enum thermal_notify_event notify_event;
233 };
234 
235 /**
236  * struct thermal_governor - structure that holds thermal governor information
237  * @name:	name of the governor
238  * @bind_to_tz: callback called when binding to a thermal zone.  If it
239  *		returns 0, the governor is bound to the thermal zone,
240  *		otherwise it fails.
241  * @unbind_from_tz:	callback called when a governor is unbound from a
242  *			thermal zone.
243  * @throttle:	callback called for every trip point even if temperature is
244  *		below the trip point temperature
245  * @governor_list:	node in thermal_governor_list (in thermal_core.c)
246  */
247 struct thermal_governor {
248 	char name[THERMAL_NAME_LENGTH];
249 	int (*bind_to_tz)(struct thermal_zone_device *tz);
250 	void (*unbind_from_tz)(struct thermal_zone_device *tz);
251 	int (*throttle)(struct thermal_zone_device *tz, int trip);
252 	struct list_head	governor_list;
253 };
254 
255 /* Structure that holds binding parameters for a zone */
256 struct thermal_bind_params {
257 	struct thermal_cooling_device *cdev;
258 
259 	/*
260 	 * This is a measure of 'how effectively these devices can
261 	 * cool 'this' thermal zone. It shall be determined by
262 	 * platform characterization. This value is relative to the
263 	 * rest of the weights so a cooling device whose weight is
264 	 * double that of another cooling device is twice as
265 	 * effective. See Documentation/thermal/sysfs-api.txt for more
266 	 * information.
267 	 */
268 	int weight;
269 
270 	/*
271 	 * This is a bit mask that gives the binding relation between this
272 	 * thermal zone and cdev, for a particular trip point.
273 	 * See Documentation/thermal/sysfs-api.txt for more information.
274 	 */
275 	int trip_mask;
276 
277 	/*
278 	 * This is an array of cooling state limits. Must have exactly
279 	 * 2 * thermal_zone.number_of_trip_points. It is an array consisting
280 	 * of tuples <lower-state upper-state> of state limits. Each trip
281 	 * will be associated with one state limit tuple when binding.
282 	 * A NULL pointer means <THERMAL_NO_LIMITS THERMAL_NO_LIMITS>
283 	 * on all trips.
284 	 */
285 	unsigned long *binding_limits;
286 	int (*match) (struct thermal_zone_device *tz,
287 			struct thermal_cooling_device *cdev);
288 };
289 
290 /* Structure to define Thermal Zone parameters */
291 struct thermal_zone_params {
292 	char governor_name[THERMAL_NAME_LENGTH];
293 
294 	/*
295 	 * a boolean to indicate if the thermal to hwmon sysfs interface
296 	 * is required. when no_hwmon == false, a hwmon sysfs interface
297 	 * will be created. when no_hwmon == true, nothing will be done
298 	 */
299 	bool no_hwmon;
300 
301 	int num_tbps;	/* Number of tbp entries */
302 	struct thermal_bind_params *tbp;
303 
304 	/*
305 	 * Sustainable power (heat) that this thermal zone can dissipate in
306 	 * mW
307 	 */
308 	u32 sustainable_power;
309 
310 	/*
311 	 * Proportional parameter of the PID controller when
312 	 * overshooting (i.e., when temperature is below the target)
313 	 */
314 	s32 k_po;
315 
316 	/*
317 	 * Proportional parameter of the PID controller when
318 	 * undershooting
319 	 */
320 	s32 k_pu;
321 
322 	/* Integral parameter of the PID controller */
323 	s32 k_i;
324 
325 	/* Derivative parameter of the PID controller */
326 	s32 k_d;
327 
328 	/* threshold below which the error is no longer accumulated */
329 	s32 integral_cutoff;
330 
331 	/*
332 	 * @slope:	slope of a linear temperature adjustment curve.
333 	 * 		Used by thermal zone drivers.
334 	 */
335 	int slope;
336 	/*
337 	 * @offset:	offset of a linear temperature adjustment curve.
338 	 * 		Used by thermal zone drivers (default 0).
339 	 */
340 	int offset;
341 };
342 
343 struct thermal_genl_event {
344 	u32 orig;
345 	enum events event;
346 };
347 
348 /**
349  * struct thermal_zone_of_device_ops - scallbacks for handling DT based zones
350  *
351  * Mandatory:
352  * @get_temp: a pointer to a function that reads the sensor temperature.
353  *
354  * Optional:
355  * @get_trend: a pointer to a function that reads the sensor temperature trend.
356  * @set_trips: a pointer to a function that sets a temperature window. When
357  *	       this window is left the driver must inform the thermal core via
358  *	       thermal_zone_device_update.
359  * @set_emul_temp: a pointer to a function that sets sensor emulated
360  *		   temperature.
361  * @set_trip_temp: a pointer to a function that sets the trip temperature on
362  *		   hardware.
363  */
364 struct thermal_zone_of_device_ops {
365 	int (*get_temp)(void *, int *);
366 	int (*get_trend)(void *, int, enum thermal_trend *);
367 	int (*set_trips)(void *, int, int);
368 	int (*set_emul_temp)(void *, int);
369 	int (*set_trip_temp)(void *, int, int);
370 };
371 
372 /**
373  * struct thermal_trip - representation of a point in temperature domain
374  * @np: pointer to struct device_node that this trip point was created from
375  * @temperature: temperature value in miliCelsius
376  * @hysteresis: relative hysteresis in miliCelsius
377  * @type: trip point type
378  */
379 
380 struct thermal_trip {
381 	struct device_node *np;
382 	int temperature;
383 	int hysteresis;
384 	enum thermal_trip_type type;
385 };
386 
387 /* Function declarations */
388 #ifdef CONFIG_THERMAL_OF
389 struct thermal_zone_device *
390 thermal_zone_of_sensor_register(struct device *dev, int id, void *data,
391 				const struct thermal_zone_of_device_ops *ops);
392 void thermal_zone_of_sensor_unregister(struct device *dev,
393 				       struct thermal_zone_device *tz);
394 struct thermal_zone_device *devm_thermal_zone_of_sensor_register(
395 		struct device *dev, int id, void *data,
396 		const struct thermal_zone_of_device_ops *ops);
397 void devm_thermal_zone_of_sensor_unregister(struct device *dev,
398 					    struct thermal_zone_device *tz);
399 #else
400 static inline struct thermal_zone_device *
401 thermal_zone_of_sensor_register(struct device *dev, int id, void *data,
402 				const struct thermal_zone_of_device_ops *ops)
403 {
404 	return ERR_PTR(-ENODEV);
405 }
406 
407 static inline
408 void thermal_zone_of_sensor_unregister(struct device *dev,
409 				       struct thermal_zone_device *tz)
410 {
411 }
412 
413 static inline struct thermal_zone_device *devm_thermal_zone_of_sensor_register(
414 		struct device *dev, int id, void *data,
415 		const struct thermal_zone_of_device_ops *ops)
416 {
417 	return ERR_PTR(-ENODEV);
418 }
419 
420 static inline
421 void devm_thermal_zone_of_sensor_unregister(struct device *dev,
422 					    struct thermal_zone_device *tz)
423 {
424 }
425 
426 #endif
427 
428 #if IS_ENABLED(CONFIG_THERMAL)
429 static inline bool cdev_is_power_actor(struct thermal_cooling_device *cdev)
430 {
431 	return cdev->ops->get_requested_power && cdev->ops->state2power &&
432 		cdev->ops->power2state;
433 }
434 
435 int power_actor_get_max_power(struct thermal_cooling_device *,
436 			      struct thermal_zone_device *tz, u32 *max_power);
437 int power_actor_get_min_power(struct thermal_cooling_device *,
438 			      struct thermal_zone_device *tz, u32 *min_power);
439 int power_actor_set_power(struct thermal_cooling_device *,
440 			  struct thermal_instance *, u32);
441 struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
442 		void *, struct thermal_zone_device_ops *,
443 		struct thermal_zone_params *, int, int);
444 void thermal_zone_device_unregister(struct thermal_zone_device *);
445 
446 int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
447 				     struct thermal_cooling_device *,
448 				     unsigned long, unsigned long,
449 				     unsigned int);
450 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
451 				       struct thermal_cooling_device *);
452 void thermal_zone_device_update(struct thermal_zone_device *,
453 				enum thermal_notify_event);
454 void thermal_zone_set_trips(struct thermal_zone_device *);
455 
456 struct thermal_cooling_device *thermal_cooling_device_register(char *, void *,
457 		const struct thermal_cooling_device_ops *);
458 struct thermal_cooling_device *
459 thermal_of_cooling_device_register(struct device_node *np, char *, void *,
460 				   const struct thermal_cooling_device_ops *);
461 void thermal_cooling_device_unregister(struct thermal_cooling_device *);
462 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name);
463 int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp);
464 int thermal_zone_get_slope(struct thermal_zone_device *tz);
465 int thermal_zone_get_offset(struct thermal_zone_device *tz);
466 
467 int get_tz_trend(struct thermal_zone_device *, int);
468 struct thermal_instance *get_thermal_instance(struct thermal_zone_device *,
469 		struct thermal_cooling_device *, int);
470 void thermal_cdev_update(struct thermal_cooling_device *);
471 void thermal_notify_framework(struct thermal_zone_device *, int);
472 #else
473 static inline bool cdev_is_power_actor(struct thermal_cooling_device *cdev)
474 { return false; }
475 static inline int power_actor_get_max_power(struct thermal_cooling_device *cdev,
476 			      struct thermal_zone_device *tz, u32 *max_power)
477 { return 0; }
478 static inline int power_actor_get_min_power(struct thermal_cooling_device *cdev,
479 					    struct thermal_zone_device *tz,
480 					    u32 *min_power)
481 { return -ENODEV; }
482 static inline int power_actor_set_power(struct thermal_cooling_device *cdev,
483 			  struct thermal_instance *tz, u32 power)
484 { return 0; }
485 static inline struct thermal_zone_device *thermal_zone_device_register(
486 	const char *type, int trips, int mask, void *devdata,
487 	struct thermal_zone_device_ops *ops,
488 	const struct thermal_zone_params *tzp,
489 	int passive_delay, int polling_delay)
490 { return ERR_PTR(-ENODEV); }
491 static inline void thermal_zone_device_unregister(
492 	struct thermal_zone_device *tz)
493 { }
494 static inline int thermal_zone_bind_cooling_device(
495 	struct thermal_zone_device *tz, int trip,
496 	struct thermal_cooling_device *cdev,
497 	unsigned long upper, unsigned long lower,
498 	unsigned int weight)
499 { return -ENODEV; }
500 static inline int thermal_zone_unbind_cooling_device(
501 	struct thermal_zone_device *tz, int trip,
502 	struct thermal_cooling_device *cdev)
503 { return -ENODEV; }
504 static inline void thermal_zone_device_update(struct thermal_zone_device *tz,
505 					      enum thermal_notify_event event)
506 { }
507 static inline void thermal_zone_set_trips(struct thermal_zone_device *tz)
508 { }
509 static inline struct thermal_cooling_device *
510 thermal_cooling_device_register(char *type, void *devdata,
511 	const struct thermal_cooling_device_ops *ops)
512 { return ERR_PTR(-ENODEV); }
513 static inline struct thermal_cooling_device *
514 thermal_of_cooling_device_register(struct device_node *np,
515 	char *type, void *devdata, const struct thermal_cooling_device_ops *ops)
516 { return ERR_PTR(-ENODEV); }
517 static inline void thermal_cooling_device_unregister(
518 	struct thermal_cooling_device *cdev)
519 { }
520 static inline struct thermal_zone_device *thermal_zone_get_zone_by_name(
521 		const char *name)
522 { return ERR_PTR(-ENODEV); }
523 static inline int thermal_zone_get_temp(
524 		struct thermal_zone_device *tz, int *temp)
525 { return -ENODEV; }
526 static inline int thermal_zone_get_slope(
527 		struct thermal_zone_device *tz)
528 { return -ENODEV; }
529 static inline int thermal_zone_get_offset(
530 		struct thermal_zone_device *tz)
531 { return -ENODEV; }
532 static inline int get_tz_trend(struct thermal_zone_device *tz, int trip)
533 { return -ENODEV; }
534 static inline struct thermal_instance *
535 get_thermal_instance(struct thermal_zone_device *tz,
536 	struct thermal_cooling_device *cdev, int trip)
537 { return ERR_PTR(-ENODEV); }
538 static inline void thermal_cdev_update(struct thermal_cooling_device *cdev)
539 { }
540 static inline void thermal_notify_framework(struct thermal_zone_device *tz,
541 	int trip)
542 { }
543 #endif /* CONFIG_THERMAL */
544 
545 #if defined(CONFIG_NET) && IS_ENABLED(CONFIG_THERMAL)
546 extern int thermal_generate_netlink_event(struct thermal_zone_device *tz,
547 						enum events event);
548 #else
549 static inline int thermal_generate_netlink_event(struct thermal_zone_device *tz,
550 						enum events event)
551 {
552 	return 0;
553 }
554 #endif
555 
556 #endif /* __THERMAL_H__ */
557