xref: /linux-6.15/include/linux/thermal.h (revision fe2a1bb1)
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 
33 #define THERMAL_TRIPS_NONE	-1
34 #define THERMAL_MAX_TRIPS	12
35 #define THERMAL_NAME_LENGTH	20
36 
37 /* invalid cooling state */
38 #define THERMAL_CSTATE_INVALID -1UL
39 
40 /* No upper/lower limit requirement */
41 #define THERMAL_NO_LIMIT	THERMAL_CSTATE_INVALID
42 
43 /* Unit conversion macros */
44 #define KELVIN_TO_CELSIUS(t)	(long)(((long)t-2732 >= 0) ?	\
45 				((long)t-2732+5)/10 : ((long)t-2732-5)/10)
46 #define CELSIUS_TO_KELVIN(t)	((t)*10+2732)
47 
48 /* Adding event notification support elements */
49 #define THERMAL_GENL_FAMILY_NAME                "thermal_event"
50 #define THERMAL_GENL_VERSION                    0x01
51 #define THERMAL_GENL_MCAST_GROUP_NAME           "thermal_mc_grp"
52 
53 /* Default Thermal Governor */
54 #if defined(CONFIG_THERMAL_DEFAULT_GOV_STEP_WISE)
55 #define DEFAULT_THERMAL_GOVERNOR       "step_wise"
56 #elif defined(CONFIG_THERMAL_DEFAULT_GOV_FAIR_SHARE)
57 #define DEFAULT_THERMAL_GOVERNOR       "fair_share"
58 #elif defined(CONFIG_THERMAL_DEFAULT_GOV_USER_SPACE)
59 #define DEFAULT_THERMAL_GOVERNOR       "user_space"
60 #endif
61 
62 struct thermal_zone_device;
63 struct thermal_cooling_device;
64 
65 enum thermal_device_mode {
66 	THERMAL_DEVICE_DISABLED = 0,
67 	THERMAL_DEVICE_ENABLED,
68 };
69 
70 enum thermal_trip_type {
71 	THERMAL_TRIP_ACTIVE = 0,
72 	THERMAL_TRIP_PASSIVE,
73 	THERMAL_TRIP_HOT,
74 	THERMAL_TRIP_CRITICAL,
75 };
76 
77 enum thermal_trend {
78 	THERMAL_TREND_STABLE, /* temperature is stable */
79 	THERMAL_TREND_RAISING, /* temperature is raising */
80 	THERMAL_TREND_DROPPING, /* temperature is dropping */
81 	THERMAL_TREND_RAISE_FULL, /* apply highest cooling action */
82 	THERMAL_TREND_DROP_FULL, /* apply lowest cooling action */
83 };
84 
85 /* Events supported by Thermal Netlink */
86 enum events {
87 	THERMAL_AUX0,
88 	THERMAL_AUX1,
89 	THERMAL_CRITICAL,
90 	THERMAL_DEV_FAULT,
91 };
92 
93 /* attributes of thermal_genl_family */
94 enum {
95 	THERMAL_GENL_ATTR_UNSPEC,
96 	THERMAL_GENL_ATTR_EVENT,
97 	__THERMAL_GENL_ATTR_MAX,
98 };
99 #define THERMAL_GENL_ATTR_MAX (__THERMAL_GENL_ATTR_MAX - 1)
100 
101 /* commands supported by the thermal_genl_family */
102 enum {
103 	THERMAL_GENL_CMD_UNSPEC,
104 	THERMAL_GENL_CMD_EVENT,
105 	__THERMAL_GENL_CMD_MAX,
106 };
107 #define THERMAL_GENL_CMD_MAX (__THERMAL_GENL_CMD_MAX - 1)
108 
109 struct thermal_zone_device_ops {
110 	int (*bind) (struct thermal_zone_device *,
111 		     struct thermal_cooling_device *);
112 	int (*unbind) (struct thermal_zone_device *,
113 		       struct thermal_cooling_device *);
114 	int (*get_temp) (struct thermal_zone_device *, unsigned long *);
115 	int (*get_mode) (struct thermal_zone_device *,
116 			 enum thermal_device_mode *);
117 	int (*set_mode) (struct thermal_zone_device *,
118 		enum thermal_device_mode);
119 	int (*get_trip_type) (struct thermal_zone_device *, int,
120 		enum thermal_trip_type *);
121 	int (*get_trip_temp) (struct thermal_zone_device *, int,
122 			      unsigned long *);
123 	int (*set_trip_temp) (struct thermal_zone_device *, int,
124 			      unsigned long);
125 	int (*get_trip_hyst) (struct thermal_zone_device *, int,
126 			      unsigned long *);
127 	int (*set_trip_hyst) (struct thermal_zone_device *, int,
128 			      unsigned long);
129 	int (*get_crit_temp) (struct thermal_zone_device *, unsigned long *);
130 	int (*set_emul_temp) (struct thermal_zone_device *, unsigned long);
131 	int (*get_trend) (struct thermal_zone_device *, int,
132 			  enum thermal_trend *);
133 	int (*notify) (struct thermal_zone_device *, int,
134 		       enum thermal_trip_type);
135 };
136 
137 struct thermal_cooling_device_ops {
138 	int (*get_max_state) (struct thermal_cooling_device *, unsigned long *);
139 	int (*get_cur_state) (struct thermal_cooling_device *, unsigned long *);
140 	int (*set_cur_state) (struct thermal_cooling_device *, 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  * @passive_delay:	number of milliseconds to wait between polls when
172  *			performing passive cooling.  Currenty only used by the
173  *			step-wise governor
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  *			Currenty only used by the step-wise governor.
184  * @forced_passive:	If > 0, temperature at which to switch on all ACPI
185  *			processor cooling devices.  Currently only used by the
186  *			step-wise governor.
187  * @ops:	operations this &thermal_zone_device supports
188  * @tzp:	thermal zone parameters
189  * @governor:	pointer to the governor for this thermal zone
190  * @thermal_instances:	list of &struct thermal_instance of this thermal zone
191  * @idr:	&struct idr to generate unique id for this zone's cooling
192  *		devices
193  * @lock:	lock to protect thermal_instances list
194  * @node:	node in thermal_tz_list (in thermal_core.c)
195  * @poll_queue:	delayed work for polling
196  */
197 struct thermal_zone_device {
198 	int id;
199 	char type[THERMAL_NAME_LENGTH];
200 	struct device device;
201 	struct thermal_attr *trip_temp_attrs;
202 	struct thermal_attr *trip_type_attrs;
203 	struct thermal_attr *trip_hyst_attrs;
204 	void *devdata;
205 	int trips;
206 	int passive_delay;
207 	int polling_delay;
208 	int temperature;
209 	int last_temperature;
210 	int emul_temperature;
211 	int passive;
212 	unsigned int forced_passive;
213 	struct thermal_zone_device_ops *ops;
214 	const struct thermal_zone_params *tzp;
215 	struct thermal_governor *governor;
216 	struct list_head thermal_instances;
217 	struct idr idr;
218 	struct mutex lock;
219 	struct list_head node;
220 	struct delayed_work poll_queue;
221 };
222 
223 /**
224  * struct thermal_governor - structure that holds thermal governor information
225  * @name:	name of the governor
226  * @throttle:	callback called for every trip point even if temperature is
227  *		below the trip point temperature
228  * @governor_list:	node in thermal_governor_list (in thermal_core.c)
229  */
230 struct thermal_governor {
231 	char name[THERMAL_NAME_LENGTH];
232 	int (*throttle)(struct thermal_zone_device *tz, int trip);
233 	struct list_head	governor_list;
234 };
235 
236 /* Structure that holds binding parameters for a zone */
237 struct thermal_bind_params {
238 	struct thermal_cooling_device *cdev;
239 
240 	/*
241 	 * This is a measure of 'how effectively these devices can
242 	 * cool 'this' thermal zone. The shall be determined by platform
243 	 * characterization. This is on a 'percentage' scale.
244 	 * See Documentation/thermal/sysfs-api.txt for more information.
245 	 */
246 	int weight;
247 
248 	/*
249 	 * This is a bit mask that gives the binding relation between this
250 	 * thermal zone and cdev, for a particular trip point.
251 	 * See Documentation/thermal/sysfs-api.txt for more information.
252 	 */
253 	int trip_mask;
254 
255 	/*
256 	 * This is an array of cooling state limits. Must have exactly
257 	 * 2 * thermal_zone.number_of_trip_points. It is an array consisting
258 	 * of tuples <lower-state upper-state> of state limits. Each trip
259 	 * will be associated with one state limit tuple when binding.
260 	 * A NULL pointer means <THERMAL_NO_LIMITS THERMAL_NO_LIMITS>
261 	 * on all trips.
262 	 */
263 	unsigned long *binding_limits;
264 	int (*match) (struct thermal_zone_device *tz,
265 			struct thermal_cooling_device *cdev);
266 };
267 
268 /* Structure to define Thermal Zone parameters */
269 struct thermal_zone_params {
270 	char governor_name[THERMAL_NAME_LENGTH];
271 
272 	/*
273 	 * a boolean to indicate if the thermal to hwmon sysfs interface
274 	 * is required. when no_hwmon == false, a hwmon sysfs interface
275 	 * will be created. when no_hwmon == true, nothing will be done
276 	 */
277 	bool no_hwmon;
278 
279 	int num_tbps;	/* Number of tbp entries */
280 	struct thermal_bind_params *tbp;
281 };
282 
283 struct thermal_genl_event {
284 	u32 orig;
285 	enum events event;
286 };
287 
288 /* Function declarations */
289 #ifdef CONFIG_THERMAL_OF
290 struct thermal_zone_device *
291 thermal_zone_of_sensor_register(struct device *dev, int id,
292 				void *data, int (*get_temp)(void *, long *),
293 				int (*get_trend)(void *, long *));
294 void thermal_zone_of_sensor_unregister(struct device *dev,
295 				       struct thermal_zone_device *tz);
296 #else
297 static inline struct thermal_zone_device *
298 thermal_zone_of_sensor_register(struct device *dev, int id,
299 				void *data, int (*get_temp)(void *, long *),
300 				int (*get_trend)(void *, long *))
301 {
302 	return NULL;
303 }
304 
305 static inline
306 void thermal_zone_of_sensor_unregister(struct device *dev,
307 				       struct thermal_zone_device *tz)
308 {
309 }
310 
311 #endif
312 struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
313 		void *, struct thermal_zone_device_ops *,
314 		const struct thermal_zone_params *, int, int);
315 void thermal_zone_device_unregister(struct thermal_zone_device *);
316 
317 int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
318 				     struct thermal_cooling_device *,
319 				     unsigned long, unsigned long);
320 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
321 				       struct thermal_cooling_device *);
322 void thermal_zone_device_update(struct thermal_zone_device *);
323 
324 struct thermal_cooling_device *thermal_cooling_device_register(char *, void *,
325 		const struct thermal_cooling_device_ops *);
326 struct thermal_cooling_device *
327 thermal_of_cooling_device_register(struct device_node *np, char *, void *,
328 				   const struct thermal_cooling_device_ops *);
329 void thermal_cooling_device_unregister(struct thermal_cooling_device *);
330 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name);
331 int thermal_zone_get_temp(struct thermal_zone_device *tz, unsigned long *temp);
332 
333 int get_tz_trend(struct thermal_zone_device *, int);
334 struct thermal_instance *get_thermal_instance(struct thermal_zone_device *,
335 		struct thermal_cooling_device *, int);
336 void thermal_cdev_update(struct thermal_cooling_device *);
337 void thermal_notify_framework(struct thermal_zone_device *, int);
338 
339 #ifdef CONFIG_NET
340 extern int thermal_generate_netlink_event(struct thermal_zone_device *tz,
341 						enum events event);
342 #else
343 static inline int thermal_generate_netlink_event(struct thermal_zone_device *tz,
344 						enum events event)
345 {
346 	return 0;
347 }
348 #endif
349 
350 #endif /* __THERMAL_H__ */
351