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