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_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 };
55 
56 struct thermal_zone_device_ops {
57 	int (*bind) (struct thermal_zone_device *,
58 		     struct thermal_cooling_device *);
59 	int (*unbind) (struct thermal_zone_device *,
60 		       struct thermal_cooling_device *);
61 	int (*get_temp) (struct thermal_zone_device *, int *);
62 	int (*set_trips) (struct thermal_zone_device *, int, int);
63 	int (*change_mode) (struct thermal_zone_device *,
64 		enum thermal_device_mode);
65 	int (*get_trip_type) (struct thermal_zone_device *, int,
66 		enum thermal_trip_type *);
67 	int (*get_trip_temp) (struct thermal_zone_device *, int, int *);
68 	int (*set_trip_temp) (struct thermal_zone_device *, int, int);
69 	int (*get_trip_hyst) (struct thermal_zone_device *, int, int *);
70 	int (*set_trip_hyst) (struct thermal_zone_device *, int, int);
71 	int (*get_crit_temp) (struct thermal_zone_device *, int *);
72 	int (*set_emul_temp) (struct thermal_zone_device *, int);
73 	int (*get_trend) (struct thermal_zone_device *, int,
74 			  enum thermal_trend *);
75 	void (*hot)(struct thermal_zone_device *);
76 	void (*critical)(struct thermal_zone_device *);
77 };
78 
79 /**
80  * struct thermal_trip - representation of a point in temperature domain
81  * @temperature: temperature value in miliCelsius
82  * @hysteresis: relative hysteresis in miliCelsius
83  * @type: trip point type
84  */
85 struct thermal_trip {
86 	int temperature;
87 	int hysteresis;
88 	enum thermal_trip_type type;
89 };
90 
91 struct thermal_cooling_device_ops {
92 	int (*get_max_state) (struct thermal_cooling_device *, unsigned long *);
93 	int (*get_cur_state) (struct thermal_cooling_device *, unsigned long *);
94 	int (*set_cur_state) (struct thermal_cooling_device *, unsigned long);
95 	int (*get_requested_power)(struct thermal_cooling_device *, u32 *);
96 	int (*state2power)(struct thermal_cooling_device *, unsigned long, u32 *);
97 	int (*power2state)(struct thermal_cooling_device *, u32, unsigned long *);
98 };
99 
100 struct thermal_cooling_device {
101 	int id;
102 	char *type;
103 	unsigned long max_state;
104 	struct device device;
105 	struct device_node *np;
106 	void *devdata;
107 	void *stats;
108 	const struct thermal_cooling_device_ops *ops;
109 	bool updated; /* true if the cooling device does not need update */
110 	struct mutex lock; /* protect thermal_instances list */
111 	struct list_head thermal_instances;
112 	struct list_head node;
113 };
114 
115 /**
116  * struct thermal_zone_device - structure for a thermal zone
117  * @id:		unique id number for each thermal zone
118  * @type:	the thermal zone device type
119  * @device:	&struct device for this thermal zone
120  * @trip_temp_attrs:	attributes for trip points for sysfs: trip temperature
121  * @trip_type_attrs:	attributes for trip points for sysfs: trip type
122  * @trip_hyst_attrs:	attributes for trip points for sysfs: trip hysteresis
123  * @mode:		current mode of this thermal zone
124  * @devdata:	private pointer for device private data
125  * @trips:	an array of struct thermal_trip
126  * @num_trips:	number of trip points the thermal zone supports
127  * @trips_disabled;	bitmap for disabled trips
128  * @passive_delay_jiffies: number of jiffies to wait between polls when
129  *			performing passive cooling.
130  * @polling_delay_jiffies: number of jiffies to wait between polls when
131  *			checking whether trip points have been crossed (0 for
132  *			interrupt driven systems)
133  * @temperature:	current temperature.  This is only for core code,
134  *			drivers should use thermal_zone_get_temp() to get the
135  *			current temperature
136  * @last_temperature:	previous temperature read
137  * @emul_temperature:	emulated temperature when using CONFIG_THERMAL_EMULATION
138  * @passive:		1 if you've crossed a passive trip point, 0 otherwise.
139  * @prev_low_trip:	the low current temperature if you've crossed a passive
140 			trip point.
141  * @prev_high_trip:	the above current temperature if you've crossed a
142 			passive trip point.
143  * @need_update:	if equals 1, thermal_zone_device_update needs to be invoked.
144  * @ops:	operations this &thermal_zone_device supports
145  * @tzp:	thermal zone parameters
146  * @governor:	pointer to the governor for this thermal zone
147  * @governor_data:	private pointer for governor data
148  * @thermal_instances:	list of &struct thermal_instance of this thermal zone
149  * @ida:	&struct ida to generate unique id for this zone's cooling
150  *		devices
151  * @lock:	lock to protect thermal_instances list
152  * @node:	node in thermal_tz_list (in thermal_core.c)
153  * @poll_queue:	delayed work for polling
154  * @notify_event: Last notification event
155  */
156 struct thermal_zone_device {
157 	int id;
158 	char type[THERMAL_NAME_LENGTH];
159 	struct device device;
160 	struct attribute_group trips_attribute_group;
161 	struct thermal_attr *trip_temp_attrs;
162 	struct thermal_attr *trip_type_attrs;
163 	struct thermal_attr *trip_hyst_attrs;
164 	enum thermal_device_mode mode;
165 	void *devdata;
166 	struct thermal_trip *trips;
167 	int num_trips;
168 	unsigned long trips_disabled;	/* bitmap for disabled trips */
169 	unsigned long passive_delay_jiffies;
170 	unsigned long polling_delay_jiffies;
171 	int temperature;
172 	int last_temperature;
173 	int emul_temperature;
174 	int passive;
175 	int prev_low_trip;
176 	int prev_high_trip;
177 	atomic_t need_update;
178 	struct thermal_zone_device_ops *ops;
179 	struct thermal_zone_params *tzp;
180 	struct thermal_governor *governor;
181 	void *governor_data;
182 	struct list_head thermal_instances;
183 	struct ida ida;
184 	struct mutex lock;
185 	struct list_head node;
186 	struct delayed_work poll_queue;
187 	enum thermal_notify_event notify_event;
188 };
189 
190 /**
191  * struct thermal_governor - structure that holds thermal governor information
192  * @name:	name of the governor
193  * @bind_to_tz: callback called when binding to a thermal zone.  If it
194  *		returns 0, the governor is bound to the thermal zone,
195  *		otherwise it fails.
196  * @unbind_from_tz:	callback called when a governor is unbound from a
197  *			thermal zone.
198  * @throttle:	callback called for every trip point even if temperature is
199  *		below the trip point temperature
200  * @governor_list:	node in thermal_governor_list (in thermal_core.c)
201  */
202 struct thermal_governor {
203 	char name[THERMAL_NAME_LENGTH];
204 	int (*bind_to_tz)(struct thermal_zone_device *tz);
205 	void (*unbind_from_tz)(struct thermal_zone_device *tz);
206 	int (*throttle)(struct thermal_zone_device *tz, int trip);
207 	struct list_head	governor_list;
208 };
209 
210 /* Structure that holds binding parameters for a zone */
211 struct thermal_bind_params {
212 	struct thermal_cooling_device *cdev;
213 
214 	/*
215 	 * This is a measure of 'how effectively these devices can
216 	 * cool 'this' thermal zone. It shall be determined by
217 	 * platform characterization. This value is relative to the
218 	 * rest of the weights so a cooling device whose weight is
219 	 * double that of another cooling device is twice as
220 	 * effective. See Documentation/driver-api/thermal/sysfs-api.rst for more
221 	 * information.
222 	 */
223 	int weight;
224 
225 	/*
226 	 * This is a bit mask that gives the binding relation between this
227 	 * thermal zone and cdev, for a particular trip point.
228 	 * See Documentation/driver-api/thermal/sysfs-api.rst for more information.
229 	 */
230 	int trip_mask;
231 
232 	/*
233 	 * This is an array of cooling state limits. Must have exactly
234 	 * 2 * thermal_zone.number_of_trip_points. It is an array consisting
235 	 * of tuples <lower-state upper-state> of state limits. Each trip
236 	 * will be associated with one state limit tuple when binding.
237 	 * A NULL pointer means <THERMAL_NO_LIMITS THERMAL_NO_LIMITS>
238 	 * on all trips.
239 	 */
240 	unsigned long *binding_limits;
241 	int (*match) (struct thermal_zone_device *tz,
242 			struct thermal_cooling_device *cdev);
243 };
244 
245 /* Structure to define Thermal Zone parameters */
246 struct thermal_zone_params {
247 	char governor_name[THERMAL_NAME_LENGTH];
248 
249 	/*
250 	 * a boolean to indicate if the thermal to hwmon sysfs interface
251 	 * is required. when no_hwmon == false, a hwmon sysfs interface
252 	 * will be created. when no_hwmon == true, nothing will be done
253 	 */
254 	bool no_hwmon;
255 
256 	int num_tbps;	/* Number of tbp entries */
257 	struct thermal_bind_params *tbp;
258 
259 	/*
260 	 * Sustainable power (heat) that this thermal zone can dissipate in
261 	 * mW
262 	 */
263 	u32 sustainable_power;
264 
265 	/*
266 	 * Proportional parameter of the PID controller when
267 	 * overshooting (i.e., when temperature is below the target)
268 	 */
269 	s32 k_po;
270 
271 	/*
272 	 * Proportional parameter of the PID controller when
273 	 * undershooting
274 	 */
275 	s32 k_pu;
276 
277 	/* Integral parameter of the PID controller */
278 	s32 k_i;
279 
280 	/* Derivative parameter of the PID controller */
281 	s32 k_d;
282 
283 	/* threshold below which the error is no longer accumulated */
284 	s32 integral_cutoff;
285 
286 	/*
287 	 * @slope:	slope of a linear temperature adjustment curve.
288 	 * 		Used by thermal zone drivers.
289 	 */
290 	int slope;
291 	/*
292 	 * @offset:	offset of a linear temperature adjustment curve.
293 	 * 		Used by thermal zone drivers (default 0).
294 	 */
295 	int offset;
296 };
297 
298 /* Function declarations */
299 #ifdef CONFIG_THERMAL_OF
300 struct thermal_zone_device *thermal_of_zone_register(struct device_node *sensor, int id, void *data,
301 						     const struct thermal_zone_device_ops *ops);
302 
303 struct thermal_zone_device *devm_thermal_of_zone_register(struct device *dev, int id, void *data,
304 							  const struct thermal_zone_device_ops *ops);
305 
306 void thermal_of_zone_unregister(struct thermal_zone_device *tz);
307 
308 void devm_thermal_of_zone_unregister(struct device *dev, struct thermal_zone_device *tz);
309 
310 void thermal_of_zone_unregister(struct thermal_zone_device *tz);
311 
312 #else
313 static inline
thermal_of_zone_register(struct device_node * sensor,int id,void * data,const struct thermal_zone_device_ops * ops)314 struct thermal_zone_device *thermal_of_zone_register(struct device_node *sensor, int id, void *data,
315 						     const struct thermal_zone_device_ops *ops)
316 {
317 	return ERR_PTR(-ENOTSUPP);
318 }
319 
320 static inline
devm_thermal_of_zone_register(struct device * dev,int id,void * data,const struct thermal_zone_device_ops * ops)321 struct thermal_zone_device *devm_thermal_of_zone_register(struct device *dev, int id, void *data,
322 							  const struct thermal_zone_device_ops *ops)
323 {
324 	return ERR_PTR(-ENOTSUPP);
325 }
326 
thermal_of_zone_unregister(struct thermal_zone_device * tz)327 static inline void thermal_of_zone_unregister(struct thermal_zone_device *tz)
328 {
329 }
330 
devm_thermal_of_zone_unregister(struct device * dev,struct thermal_zone_device * tz)331 static inline void devm_thermal_of_zone_unregister(struct device *dev,
332 						   struct thermal_zone_device *tz)
333 {
334 }
335 #endif
336 
337 #ifdef CONFIG_THERMAL
338 struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
339 		void *, struct thermal_zone_device_ops *,
340 		struct thermal_zone_params *, int, int);
341 
342 void thermal_zone_device_unregister(struct thermal_zone_device *);
343 
344 struct thermal_zone_device *
345 thermal_zone_device_register_with_trips(const char *, struct thermal_trip *, int, int,
346 					void *, struct thermal_zone_device_ops *,
347 					struct thermal_zone_params *, int, int);
348 
349 int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
350 				     struct thermal_cooling_device *,
351 				     unsigned long, unsigned long,
352 				     unsigned int);
353 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
354 				       struct thermal_cooling_device *);
355 void thermal_zone_device_update(struct thermal_zone_device *,
356 				enum thermal_notify_event);
357 
358 struct thermal_cooling_device *thermal_cooling_device_register(const char *,
359 		void *, const struct thermal_cooling_device_ops *);
360 struct thermal_cooling_device *
361 thermal_of_cooling_device_register(struct device_node *np, const char *, void *,
362 				   const struct thermal_cooling_device_ops *);
363 struct thermal_cooling_device *
364 devm_thermal_of_cooling_device_register(struct device *dev,
365 				struct device_node *np,
366 				char *type, void *devdata,
367 				const struct thermal_cooling_device_ops *ops);
368 void thermal_cooling_device_unregister(struct thermal_cooling_device *);
369 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name);
370 int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp);
371 int thermal_zone_get_slope(struct thermal_zone_device *tz);
372 int thermal_zone_get_offset(struct thermal_zone_device *tz);
373 
374 int thermal_zone_device_enable(struct thermal_zone_device *tz);
375 int thermal_zone_device_disable(struct thermal_zone_device *tz);
376 void thermal_zone_device_critical(struct thermal_zone_device *tz);
377 #else
thermal_zone_device_register(const char * type,int trips,int mask,void * devdata,struct thermal_zone_device_ops * ops,struct thermal_zone_params * tzp,int passive_delay,int polling_delay)378 static inline struct thermal_zone_device *thermal_zone_device_register(
379 	const char *type, int trips, int mask, void *devdata,
380 	struct thermal_zone_device_ops *ops,
381 	struct thermal_zone_params *tzp,
382 	int passive_delay, int polling_delay)
383 { return ERR_PTR(-ENODEV); }
thermal_zone_device_unregister(struct thermal_zone_device * tz)384 static inline void thermal_zone_device_unregister(
385 	struct thermal_zone_device *tz)
386 { }
387 static inline struct thermal_cooling_device *
thermal_cooling_device_register(const char * type,void * devdata,const struct thermal_cooling_device_ops * ops)388 thermal_cooling_device_register(const char *type, void *devdata,
389 	const struct thermal_cooling_device_ops *ops)
390 { return ERR_PTR(-ENODEV); }
391 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)392 thermal_of_cooling_device_register(struct device_node *np,
393 	const char *type, void *devdata,
394 	const struct thermal_cooling_device_ops *ops)
395 { return ERR_PTR(-ENODEV); }
396 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)397 devm_thermal_of_cooling_device_register(struct device *dev,
398 				struct device_node *np,
399 				char *type, void *devdata,
400 				const struct thermal_cooling_device_ops *ops)
401 {
402 	return ERR_PTR(-ENODEV);
403 }
thermal_cooling_device_unregister(struct thermal_cooling_device * cdev)404 static inline void thermal_cooling_device_unregister(
405 	struct thermal_cooling_device *cdev)
406 { }
thermal_zone_get_zone_by_name(const char * name)407 static inline struct thermal_zone_device *thermal_zone_get_zone_by_name(
408 		const char *name)
409 { return ERR_PTR(-ENODEV); }
thermal_zone_get_temp(struct thermal_zone_device * tz,int * temp)410 static inline int thermal_zone_get_temp(
411 		struct thermal_zone_device *tz, int *temp)
412 { return -ENODEV; }
thermal_zone_get_slope(struct thermal_zone_device * tz)413 static inline int thermal_zone_get_slope(
414 		struct thermal_zone_device *tz)
415 { return -ENODEV; }
thermal_zone_get_offset(struct thermal_zone_device * tz)416 static inline int thermal_zone_get_offset(
417 		struct thermal_zone_device *tz)
418 { return -ENODEV; }
419 
thermal_zone_device_enable(struct thermal_zone_device * tz)420 static inline int thermal_zone_device_enable(struct thermal_zone_device *tz)
421 { return -ENODEV; }
422 
thermal_zone_device_disable(struct thermal_zone_device * tz)423 static inline int thermal_zone_device_disable(struct thermal_zone_device *tz)
424 { return -ENODEV; }
425 #endif /* CONFIG_THERMAL */
426 
427 #endif /* __THERMAL_H__ */
428