xref: /linux-6.15/include/linux/thermal.h (revision bb3fc5dd)
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 /* Unit conversion macros */
47 #define KELVIN_TO_CELSIUS(t)	(long)(((long)t-2732 >= 0) ?	\
48 				((long)t-2732+5)/10 : ((long)t-2732-5)/10)
49 #define CELSIUS_TO_KELVIN(t)	((t)*10+2732)
50 #define DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(t, off) (((t) - (off)) * 100)
51 #define DECI_KELVIN_TO_MILLICELSIUS(t) DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(t, 2732)
52 #define MILLICELSIUS_TO_DECI_KELVIN_WITH_OFFSET(t, off) (((t) / 100) + (off))
53 #define MILLICELSIUS_TO_DECI_KELVIN(t) MILLICELSIUS_TO_DECI_KELVIN_WITH_OFFSET(t, 2732)
54 
55 /* Default Thermal Governor */
56 #if defined(CONFIG_THERMAL_DEFAULT_GOV_STEP_WISE)
57 #define DEFAULT_THERMAL_GOVERNOR       "step_wise"
58 #elif defined(CONFIG_THERMAL_DEFAULT_GOV_FAIR_SHARE)
59 #define DEFAULT_THERMAL_GOVERNOR       "fair_share"
60 #elif defined(CONFIG_THERMAL_DEFAULT_GOV_USER_SPACE)
61 #define DEFAULT_THERMAL_GOVERNOR       "user_space"
62 #elif defined(CONFIG_THERMAL_DEFAULT_GOV_POWER_ALLOCATOR)
63 #define DEFAULT_THERMAL_GOVERNOR       "power_allocator"
64 #endif
65 
66 struct thermal_zone_device;
67 struct thermal_cooling_device;
68 struct thermal_instance;
69 
70 enum thermal_device_mode {
71 	THERMAL_DEVICE_DISABLED = 0,
72 	THERMAL_DEVICE_ENABLED,
73 };
74 
75 enum thermal_trip_type {
76 	THERMAL_TRIP_ACTIVE = 0,
77 	THERMAL_TRIP_PASSIVE,
78 	THERMAL_TRIP_HOT,
79 	THERMAL_TRIP_CRITICAL,
80 };
81 
82 enum thermal_trend {
83 	THERMAL_TREND_STABLE, /* temperature is stable */
84 	THERMAL_TREND_RAISING, /* temperature is raising */
85 	THERMAL_TREND_DROPPING, /* temperature is dropping */
86 	THERMAL_TREND_RAISE_FULL, /* apply highest cooling action */
87 	THERMAL_TREND_DROP_FULL, /* apply lowest cooling action */
88 };
89 
90 struct thermal_zone_device_ops {
91 	int (*bind) (struct thermal_zone_device *,
92 		     struct thermal_cooling_device *);
93 	int (*unbind) (struct thermal_zone_device *,
94 		       struct thermal_cooling_device *);
95 	int (*get_temp) (struct thermal_zone_device *, int *);
96 	int (*get_mode) (struct thermal_zone_device *,
97 			 enum thermal_device_mode *);
98 	int (*set_mode) (struct thermal_zone_device *,
99 		enum thermal_device_mode);
100 	int (*get_trip_type) (struct thermal_zone_device *, int,
101 		enum thermal_trip_type *);
102 	int (*get_trip_temp) (struct thermal_zone_device *, int, int *);
103 	int (*set_trip_temp) (struct thermal_zone_device *, int, int);
104 	int (*get_trip_hyst) (struct thermal_zone_device *, int, int *);
105 	int (*set_trip_hyst) (struct thermal_zone_device *, int, int);
106 	int (*get_crit_temp) (struct thermal_zone_device *, int *);
107 	int (*set_emul_temp) (struct thermal_zone_device *, int);
108 	int (*get_trend) (struct thermal_zone_device *, int,
109 			  enum thermal_trend *);
110 	int (*notify) (struct thermal_zone_device *, int,
111 		       enum thermal_trip_type);
112 };
113 
114 struct thermal_cooling_device_ops {
115 	int (*get_max_state) (struct thermal_cooling_device *, unsigned long *);
116 	int (*get_cur_state) (struct thermal_cooling_device *, unsigned long *);
117 	int (*set_cur_state) (struct thermal_cooling_device *, unsigned long);
118 	int (*get_requested_power)(struct thermal_cooling_device *,
119 				   struct thermal_zone_device *, u32 *);
120 	int (*state2power)(struct thermal_cooling_device *,
121 			   struct thermal_zone_device *, unsigned long, u32 *);
122 	int (*power2state)(struct thermal_cooling_device *,
123 			   struct thermal_zone_device *, u32, unsigned long *);
124 };
125 
126 struct thermal_cooling_device {
127 	int id;
128 	char type[THERMAL_NAME_LENGTH];
129 	struct device device;
130 	struct device_node *np;
131 	void *devdata;
132 	const struct thermal_cooling_device_ops *ops;
133 	bool updated; /* true if the cooling device does not need update */
134 	struct mutex lock; /* protect thermal_instances list */
135 	struct list_head thermal_instances;
136 	struct list_head node;
137 };
138 
139 struct thermal_attr {
140 	struct device_attribute attr;
141 	char name[THERMAL_NAME_LENGTH];
142 };
143 
144 /**
145  * struct thermal_zone_device - structure for a thermal zone
146  * @id:		unique id number for each thermal zone
147  * @type:	the thermal zone device type
148  * @device:	&struct device for this thermal zone
149  * @trip_temp_attrs:	attributes for trip points for sysfs: trip temperature
150  * @trip_type_attrs:	attributes for trip points for sysfs: trip type
151  * @trip_hyst_attrs:	attributes for trip points for sysfs: trip hysteresis
152  * @devdata:	private pointer for device private data
153  * @trips:	number of trip points the thermal zone supports
154  * @passive_delay:	number of milliseconds to wait between polls when
155  *			performing passive cooling.
156  * @polling_delay:	number of milliseconds to wait between polls when
157  *			checking whether trip points have been crossed (0 for
158  *			interrupt driven systems)
159  * @temperature:	current temperature.  This is only for core code,
160  *			drivers should use thermal_zone_get_temp() to get the
161  *			current temperature
162  * @last_temperature:	previous temperature read
163  * @emul_temperature:	emulated temperature when using CONFIG_THERMAL_EMULATION
164  * @passive:		1 if you've crossed a passive trip point, 0 otherwise.
165  * @forced_passive:	If > 0, temperature at which to switch on all ACPI
166  *			processor cooling devices.  Currently only used by the
167  *			step-wise governor.
168  * @ops:	operations this &thermal_zone_device supports
169  * @tzp:	thermal zone parameters
170  * @governor:	pointer to the governor for this thermal zone
171  * @governor_data:	private pointer for governor data
172  * @thermal_instances:	list of &struct thermal_instance of this thermal zone
173  * @idr:	&struct idr to generate unique id for this zone's cooling
174  *		devices
175  * @lock:	lock to protect thermal_instances list
176  * @node:	node in thermal_tz_list (in thermal_core.c)
177  * @poll_queue:	delayed work for polling
178  */
179 struct thermal_zone_device {
180 	int id;
181 	char type[THERMAL_NAME_LENGTH];
182 	struct device device;
183 	struct thermal_attr *trip_temp_attrs;
184 	struct thermal_attr *trip_type_attrs;
185 	struct thermal_attr *trip_hyst_attrs;
186 	void *devdata;
187 	int trips;
188 	int passive_delay;
189 	int polling_delay;
190 	int temperature;
191 	int last_temperature;
192 	int emul_temperature;
193 	int passive;
194 	unsigned int forced_passive;
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 idr idr;
201 	struct mutex lock;
202 	struct list_head node;
203 	struct delayed_work poll_queue;
204 };
205 
206 /**
207  * struct thermal_governor - structure that holds thermal governor information
208  * @name:	name of the governor
209  * @bind_to_tz: callback called when binding to a thermal zone.  If it
210  *		returns 0, the governor is bound to the thermal zone,
211  *		otherwise it fails.
212  * @unbind_from_tz:	callback called when a governor is unbound from a
213  *			thermal zone.
214  * @throttle:	callback called for every trip point even if temperature is
215  *		below the trip point temperature
216  * @governor_list:	node in thermal_governor_list (in thermal_core.c)
217  */
218 struct thermal_governor {
219 	char name[THERMAL_NAME_LENGTH];
220 	int (*bind_to_tz)(struct thermal_zone_device *tz);
221 	void (*unbind_from_tz)(struct thermal_zone_device *tz);
222 	int (*throttle)(struct thermal_zone_device *tz, int trip);
223 	struct list_head	governor_list;
224 };
225 
226 /* Structure that holds binding parameters for a zone */
227 struct thermal_bind_params {
228 	struct thermal_cooling_device *cdev;
229 
230 	/*
231 	 * This is a measure of 'how effectively these devices can
232 	 * cool 'this' thermal zone. It shall be determined by
233 	 * platform characterization. This value is relative to the
234 	 * rest of the weights so a cooling device whose weight is
235 	 * double that of another cooling device is twice as
236 	 * effective. See Documentation/thermal/sysfs-api.txt for more
237 	 * information.
238 	 */
239 	int weight;
240 
241 	/*
242 	 * This is a bit mask that gives the binding relation between this
243 	 * thermal zone and cdev, for a particular trip point.
244 	 * See Documentation/thermal/sysfs-api.txt for more information.
245 	 */
246 	int trip_mask;
247 
248 	/*
249 	 * This is an array of cooling state limits. Must have exactly
250 	 * 2 * thermal_zone.number_of_trip_points. It is an array consisting
251 	 * of tuples <lower-state upper-state> of state limits. Each trip
252 	 * will be associated with one state limit tuple when binding.
253 	 * A NULL pointer means <THERMAL_NO_LIMITS THERMAL_NO_LIMITS>
254 	 * on all trips.
255 	 */
256 	unsigned long *binding_limits;
257 	int (*match) (struct thermal_zone_device *tz,
258 			struct thermal_cooling_device *cdev);
259 };
260 
261 /* Structure to define Thermal Zone parameters */
262 struct thermal_zone_params {
263 	char governor_name[THERMAL_NAME_LENGTH];
264 
265 	/*
266 	 * a boolean to indicate if the thermal to hwmon sysfs interface
267 	 * is required. when no_hwmon == false, a hwmon sysfs interface
268 	 * will be created. when no_hwmon == true, nothing will be done
269 	 */
270 	bool no_hwmon;
271 
272 	int num_tbps;	/* Number of tbp entries */
273 	struct thermal_bind_params *tbp;
274 
275 	/*
276 	 * Sustainable power (heat) that this thermal zone can dissipate in
277 	 * mW
278 	 */
279 	u32 sustainable_power;
280 
281 	/*
282 	 * Proportional parameter of the PID controller when
283 	 * overshooting (i.e., when temperature is below the target)
284 	 */
285 	s32 k_po;
286 
287 	/*
288 	 * Proportional parameter of the PID controller when
289 	 * undershooting
290 	 */
291 	s32 k_pu;
292 
293 	/* Integral parameter of the PID controller */
294 	s32 k_i;
295 
296 	/* Derivative parameter of the PID controller */
297 	s32 k_d;
298 
299 	/* threshold below which the error is no longer accumulated */
300 	s32 integral_cutoff;
301 
302 	/*
303 	 * @slope:	slope of a linear temperature adjustment curve.
304 	 * 		Used by thermal zone drivers.
305 	 */
306 	int slope;
307 	/*
308 	 * @offset:	offset of a linear temperature adjustment curve.
309 	 * 		Used by thermal zone drivers (default 0).
310 	 */
311 	int offset;
312 };
313 
314 struct thermal_genl_event {
315 	u32 orig;
316 	enum events event;
317 };
318 
319 /**
320  * struct thermal_zone_of_device_ops - scallbacks for handling DT based zones
321  *
322  * Mandatory:
323  * @get_temp: a pointer to a function that reads the sensor temperature.
324  *
325  * Optional:
326  * @get_trend: a pointer to a function that reads the sensor temperature trend.
327  * @set_emul_temp: a pointer to a function that sets sensor emulated
328  *		   temperature.
329  */
330 struct thermal_zone_of_device_ops {
331 	int (*get_temp)(void *, int *);
332 	int (*get_trend)(void *, long *);
333 	int (*set_emul_temp)(void *, int);
334 };
335 
336 /**
337  * struct thermal_trip - representation of a point in temperature domain
338  * @np: pointer to struct device_node that this trip point was created from
339  * @temperature: temperature value in miliCelsius
340  * @hysteresis: relative hysteresis in miliCelsius
341  * @type: trip point type
342  */
343 
344 struct thermal_trip {
345 	struct device_node *np;
346 	unsigned long int temperature;
347 	unsigned long int hysteresis;
348 	enum thermal_trip_type type;
349 };
350 
351 /* Function declarations */
352 #ifdef CONFIG_THERMAL_OF
353 struct thermal_zone_device *
354 thermal_zone_of_sensor_register(struct device *dev, int id, void *data,
355 				const struct thermal_zone_of_device_ops *ops);
356 void thermal_zone_of_sensor_unregister(struct device *dev,
357 				       struct thermal_zone_device *tz);
358 #else
359 static inline struct thermal_zone_device *
360 thermal_zone_of_sensor_register(struct device *dev, int id, void *data,
361 				const struct thermal_zone_of_device_ops *ops)
362 {
363 	return ERR_PTR(-ENODEV);
364 }
365 
366 static inline
367 void thermal_zone_of_sensor_unregister(struct device *dev,
368 				       struct thermal_zone_device *tz)
369 {
370 }
371 
372 #endif
373 
374 #if IS_ENABLED(CONFIG_THERMAL)
375 static inline bool cdev_is_power_actor(struct thermal_cooling_device *cdev)
376 {
377 	return cdev->ops->get_requested_power && cdev->ops->state2power &&
378 		cdev->ops->power2state;
379 }
380 
381 int power_actor_get_max_power(struct thermal_cooling_device *,
382 			      struct thermal_zone_device *tz, u32 *max_power);
383 int power_actor_get_min_power(struct thermal_cooling_device *,
384 			      struct thermal_zone_device *tz, u32 *min_power);
385 int power_actor_set_power(struct thermal_cooling_device *,
386 			  struct thermal_instance *, u32);
387 struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
388 		void *, struct thermal_zone_device_ops *,
389 		struct thermal_zone_params *, int, int);
390 void thermal_zone_device_unregister(struct thermal_zone_device *);
391 
392 int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
393 				     struct thermal_cooling_device *,
394 				     unsigned long, unsigned long,
395 				     unsigned int);
396 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
397 				       struct thermal_cooling_device *);
398 void thermal_zone_device_update(struct thermal_zone_device *);
399 
400 struct thermal_cooling_device *thermal_cooling_device_register(char *, void *,
401 		const struct thermal_cooling_device_ops *);
402 struct thermal_cooling_device *
403 thermal_of_cooling_device_register(struct device_node *np, char *, void *,
404 				   const struct thermal_cooling_device_ops *);
405 void thermal_cooling_device_unregister(struct thermal_cooling_device *);
406 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name);
407 int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp);
408 
409 int get_tz_trend(struct thermal_zone_device *, int);
410 struct thermal_instance *get_thermal_instance(struct thermal_zone_device *,
411 		struct thermal_cooling_device *, int);
412 void thermal_cdev_update(struct thermal_cooling_device *);
413 void thermal_notify_framework(struct thermal_zone_device *, int);
414 #else
415 static inline bool cdev_is_power_actor(struct thermal_cooling_device *cdev)
416 { return false; }
417 static inline int power_actor_get_max_power(struct thermal_cooling_device *cdev,
418 			      struct thermal_zone_device *tz, u32 *max_power)
419 { return 0; }
420 static inline int power_actor_get_min_power(struct thermal_cooling_device *cdev,
421 					    struct thermal_zone_device *tz,
422 					    u32 *min_power)
423 { return -ENODEV; }
424 static inline int power_actor_set_power(struct thermal_cooling_device *cdev,
425 			  struct thermal_instance *tz, u32 power)
426 { return 0; }
427 static inline struct thermal_zone_device *thermal_zone_device_register(
428 	const char *type, int trips, int mask, void *devdata,
429 	struct thermal_zone_device_ops *ops,
430 	const struct thermal_zone_params *tzp,
431 	int passive_delay, int polling_delay)
432 { return ERR_PTR(-ENODEV); }
433 static inline void thermal_zone_device_unregister(
434 	struct thermal_zone_device *tz)
435 { }
436 static inline int thermal_zone_bind_cooling_device(
437 	struct thermal_zone_device *tz, int trip,
438 	struct thermal_cooling_device *cdev,
439 	unsigned long upper, unsigned long lower)
440 { return -ENODEV; }
441 static inline int thermal_zone_unbind_cooling_device(
442 	struct thermal_zone_device *tz, int trip,
443 	struct thermal_cooling_device *cdev)
444 { return -ENODEV; }
445 static inline void thermal_zone_device_update(struct thermal_zone_device *tz)
446 { }
447 static inline struct thermal_cooling_device *
448 thermal_cooling_device_register(char *type, void *devdata,
449 	const struct thermal_cooling_device_ops *ops)
450 { return ERR_PTR(-ENODEV); }
451 static inline struct thermal_cooling_device *
452 thermal_of_cooling_device_register(struct device_node *np,
453 	char *type, void *devdata, const struct thermal_cooling_device_ops *ops)
454 { return ERR_PTR(-ENODEV); }
455 static inline void thermal_cooling_device_unregister(
456 	struct thermal_cooling_device *cdev)
457 { }
458 static inline struct thermal_zone_device *thermal_zone_get_zone_by_name(
459 		const char *name)
460 { return ERR_PTR(-ENODEV); }
461 static inline int thermal_zone_get_temp(
462 		struct thermal_zone_device *tz, int *temp)
463 { return -ENODEV; }
464 static inline int get_tz_trend(struct thermal_zone_device *tz, int trip)
465 { return -ENODEV; }
466 static inline struct thermal_instance *
467 get_thermal_instance(struct thermal_zone_device *tz,
468 	struct thermal_cooling_device *cdev, int trip)
469 { return ERR_PTR(-ENODEV); }
470 static inline void thermal_cdev_update(struct thermal_cooling_device *cdev)
471 { }
472 static inline void thermal_notify_framework(struct thermal_zone_device *tz,
473 	int trip)
474 { }
475 #endif /* CONFIG_THERMAL */
476 
477 #if defined(CONFIG_NET) && IS_ENABLED(CONFIG_THERMAL)
478 extern int thermal_generate_netlink_event(struct thermal_zone_device *tz,
479 						enum events event);
480 #else
481 static inline int thermal_generate_netlink_event(struct thermal_zone_device *tz,
482 						enum events event)
483 {
484 	return 0;
485 }
486 #endif
487 
488 #endif /* __THERMAL_H__ */
489