include/linux/thermal.h

   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 #define THERMAL_MAX_TRIPS       12
  21
  22 /* invalid cooling state */
  23 #define THERMAL_CSTATE_INVALID -1UL
  24
  25 /* No upper/lower limit requirement */
  26 #define THERMAL_NO_LIMIT        ((u32)~0)
  27
  28 /* Default weight of a bound cooling device */
  29 #define THERMAL_WEIGHT_DEFAULT 0
  30
  31 /* use value, which < 0K, to indicate an invalid/uninitialized temperature */
  32 #define THERMAL_TEMP_INVALID    -274000
  33
  34 struct thermal_zone_device;
  35 struct thermal_cooling_device;
  36 struct thermal_instance;
  37 struct thermal_attr;
  38
  39 enum thermal_trend {
  40         THERMAL_TREND_STABLE, /* temperature is stable */
  41         THERMAL_TREND_RAISING, /* temperature is raising */
  42         THERMAL_TREND_DROPPING, /* temperature is dropping */
  43         THERMAL_TREND_RAISE_FULL, /* apply highest cooling action */
  44         THERMAL_TREND_DROP_FULL, /* apply lowest cooling action */
  45 };
  46
  47 /* Thermal notification reason */
  48 enum thermal_notify_event {
  49         THERMAL_EVENT_UNSPECIFIED, /* Unspecified event */
  50         THERMAL_EVENT_TEMP_SAMPLE, /* New Temperature sample */
  51         THERMAL_TRIP_VIOLATED, /* TRIP Point violation */
  52         THERMAL_TRIP_CHANGED, /* TRIP Point temperature changed */
  53         THERMAL_DEVICE_DOWN, /* Thermal device is down */
  54         THERMAL_DEVICE_UP, /* Thermal device is up after a down event */
  55         THERMAL_DEVICE_POWER_CAPABILITY_CHANGED, /* power capability changed */
  56         THERMAL_TABLE_CHANGED, /* Thermal table(s) changed */
  57         THERMAL_EVENT_KEEP_ALIVE, /* Request for user space handler to respond */
  58 };
  59
  60 struct thermal_zone_device_ops {
  61         int (*bind) (struct thermal_zone_device *,
  62                      struct thermal_cooling_device *);
  63         int (*unbind) (struct thermal_zone_device *,
  64                        struct thermal_cooling_device *);
  65         int (*get_temp) (struct thermal_zone_device *, int *);
  66         int (*set_trips) (struct thermal_zone_device *, int, int);
  67         int (*change_mode) (struct thermal_zone_device *,
  68                 enum thermal_device_mode);
  69         int (*get_trip_type) (struct thermal_zone_device *, int,
  70                 enum thermal_trip_type *);
  71         int (*get_trip_temp) (struct thermal_zone_device *, int, int *);
  72         int (*set_trip_temp) (struct thermal_zone_device *, int, int);
  73         int (*get_trip_hyst) (struct thermal_zone_device *, int, int *);
  74         int (*set_trip_hyst) (struct thermal_zone_device *, int, int);
  75         int (*get_crit_temp) (struct thermal_zone_device *, int *);
  76         int (*set_emul_temp) (struct thermal_zone_device *, int);
  77         int (*get_trend) (struct thermal_zone_device *, int,
  78                           enum thermal_trend *);
  79         void (*hot)(struct thermal_zone_device *);
  80         void (*critical)(struct thermal_zone_device *);
  81 };
  82
  83 struct thermal_cooling_device_ops {
  84         int (*get_max_state) (struct thermal_cooling_device *, unsigned long *);
  85         int (*get_cur_state) (struct thermal_cooling_device *, unsigned long *);
  86         int (*set_cur_state) (struct thermal_cooling_device *, unsigned long);
  87         int (*get_requested_power)(struct thermal_cooling_device *, u32 *);
  88         int (*state2power)(struct thermal_cooling_device *, unsigned long, u32 *);
  89         int (*power2state)(struct thermal_cooling_device *, u32, unsigned long *);
  90 };
  91
  92 struct thermal_cooling_device {
  93         int id;
  94         char *type;
  95         struct device device;
  96         struct device_node *np;
  97         void *devdata;
  98         void *stats;
  99         const struct thermal_cooling_device_ops *ops;
 100         bool updated; /* true if the cooling device does not need update */
 101         struct mutex lock; /* protect thermal_instances list */
 102         struct list_head thermal_instances;
 103         struct list_head node;
 104 };
 105
 106 /**
 107  * struct thermal_zone_device - structure for a thermal zone
 108  * @id:         unique id number for each thermal zone
 109  * @type:       the thermal zone device type
 110  * @device:     &struct device for this thermal zone
 111  * @trip_temp_attrs:    attributes for trip points for sysfs: trip temperature
 112  * @trip_type_attrs:    attributes for trip points for sysfs: trip type
 113  * @trip_hyst_attrs:    attributes for trip points for sysfs: trip hysteresis
 114  * @mode:               current mode of this thermal zone
 115  * @devdata:    private pointer for device private data
 116  * @trips:      number of trip points the thermal zone supports
 117  * @trips_disabled;     bitmap for disabled trips
 118  * @passive_delay_jiffies: number of jiffies to wait between polls when
 119  *                      performing passive cooling.
 120  * @polling_delay_jiffies: number of jiffies to wait between polls when
 121  *                      checking whether trip points have been crossed (0 for
 122  *                      interrupt driven systems)
 123  * @temperature:        current temperature.  This is only for core code,
 124  *                      drivers should use thermal_zone_get_temp() to get the
 125  *                      current temperature
 126  * @last_temperature:   previous temperature read
 127  * @emul_temperature:   emulated temperature when using CONFIG_THERMAL_EMULATION
 128  * @passive:            1 if you've crossed a passive trip point, 0 otherwise.
 129  * @prev_low_trip:      the low current temperature if you've crossed a passive
 130                         trip point.
 131  * @prev_high_trip:     the above current temperature if you've crossed a
 132                         passive trip point.
 133  * @need_update:        if equals 1, thermal_zone_device_update needs to be invoked.
 134  * @ops:        operations this &thermal_zone_device supports
 135  * @tzp:        thermal zone parameters
 136  * @governor:   pointer to the governor for this thermal zone
 137  * @governor_data:      private pointer for governor data
 138  * @thermal_instances:  list of &struct thermal_instance of this thermal zone
 139  * @ida:        &struct ida to generate unique id for this zone's cooling
 140  *              devices
 141  * @lock:       lock to protect thermal_instances list
 142  * @node:       node in thermal_tz_list (in thermal_core.c)
 143  * @poll_queue: delayed work for polling
 144  * @notify_event: Last notification event
 145  */
 146 struct thermal_zone_device {
 147         int id;
 148         char type[THERMAL_NAME_LENGTH];
 149         struct device device;
 150         struct attribute_group trips_attribute_group;
 151         struct thermal_attr *trip_temp_attrs;
 152         struct thermal_attr *trip_type_attrs;
 153         struct thermal_attr *trip_hyst_attrs;
 154         enum thermal_device_mode mode;
 155         void *devdata;
 156         int trips;
 157         unsigned long trips_disabled;   /* bitmap for disabled trips */
 158         unsigned long passive_delay_jiffies;
 159         unsigned long polling_delay_jiffies;
 160         int temperature;
 161         int last_temperature;
 162         int emul_temperature;
 163         int passive;
 164         int prev_low_trip;
 165         int prev_high_trip;
 166         atomic_t need_update;
 167         struct thermal_zone_device_ops *ops;
 168         struct thermal_zone_params *tzp;
 169         struct thermal_governor *governor;
 170         void *governor_data;
 171         struct list_head thermal_instances;
 172         struct ida ida;
 173         struct mutex lock;
 174         struct list_head node;
 175         struct delayed_work poll_queue;
 176         enum thermal_notify_event notify_event;
 177 };
 178
 179 /**
 180  * struct thermal_governor - structure that holds thermal governor information
 181  * @name:       name of the governor
 182  * @bind_to_tz: callback called when binding to a thermal zone.  If it
 183  *              returns 0, the governor is bound to the thermal zone,
 184  *              otherwise it fails.
 185  * @unbind_from_tz:     callback called when a governor is unbound from a
 186  *                      thermal zone.
 187  * @throttle:   callback called for every trip point even if temperature is
 188  *              below the trip point temperature
 189  * @governor_list:      node in thermal_governor_list (in thermal_core.c)
 190  */
 191 struct thermal_governor {
 192         char name[THERMAL_NAME_LENGTH];
 193         int (*bind_to_tz)(struct thermal_zone_device *tz);
 194         void (*unbind_from_tz)(struct thermal_zone_device *tz);
 195         int (*throttle)(struct thermal_zone_device *tz, int trip);
 196         struct list_head        governor_list;
 197 };
 198
 199 /* Structure that holds binding parameters for a zone */
 200 struct thermal_bind_params {
 201         struct thermal_cooling_device *cdev;
 202
 203         /*
 204          * This is a measure of 'how effectively these devices can
 205          * cool 'this' thermal zone. It shall be determined by
 206          * platform characterization. This value is relative to the
 207          * rest of the weights so a cooling device whose weight is
 208          * double that of another cooling device is twice as
 209          * effective. See Documentation/driver-api/thermal/sysfs-api.rst for more
 210          * information.
 211          */
 212         int weight;
 213
 214         /*
 215          * This is a bit mask that gives the binding relation between this
 216          * thermal zone and cdev, for a particular trip point.
 217          * See Documentation/driver-api/thermal/sysfs-api.rst for more information.
 218          */
 219         int trip_mask;
 220
 221         /*
 222          * This is an array of cooling state limits. Must have exactly
 223          * 2 * thermal_zone.number_of_trip_points. It is an array consisting
 224          * of tuples <lower-state upper-state> of state limits. Each trip
 225          * will be associated with one state limit tuple when binding.
 226          * A NULL pointer means <THERMAL_NO_LIMITS THERMAL_NO_LIMITS>
 227          * on all trips.
 228          */
 229         unsigned long *binding_limits;
 230         int (*match) (struct thermal_zone_device *tz,
 231                         struct thermal_cooling_device *cdev);
 232 };
 233
 234 /* Structure to define Thermal Zone parameters */
 235 struct thermal_zone_params {
 236         char governor_name[THERMAL_NAME_LENGTH];
 237
 238         /*
 239          * a boolean to indicate if the thermal to hwmon sysfs interface
 240          * is required. when no_hwmon == false, a hwmon sysfs interface
 241          * will be created. when no_hwmon == true, nothing will be done
 242          */
 243         bool no_hwmon;
 244
 245         int num_tbps;   /* Number of tbp entries */
 246         struct thermal_bind_params *tbp;
 247
 248         /*
 249          * Sustainable power (heat) that this thermal zone can dissipate in
 250          * mW
 251          */
 252         u32 sustainable_power;
 253
 254         /*
 255          * Proportional parameter of the PID controller when
 256          * overshooting (i.e., when temperature is below the target)
 257          */
 258         s32 k_po;
 259
 260         /*
 261          * Proportional parameter of the PID controller when
 262          * undershooting
 263          */
 264         s32 k_pu;
 265
 266         /* Integral parameter of the PID controller */
 267         s32 k_i;
 268
 269         /* Derivative parameter of the PID controller */
 270         s32 k_d;
 271
 272         /* threshold below which the error is no longer accumulated */
 273         s32 integral_cutoff;
 274
 275         /*
 276          * @slope:      slope of a linear temperature adjustment curve.
 277          *              Used by thermal zone drivers.
 278          */
 279         int slope;
 280         /*
 281          * @offset:     offset of a linear temperature adjustment curve.
 282          *              Used by thermal zone drivers (default 0).
 283          */
 284         int offset;
 285 };
 286
 287 /**
 288  * struct thermal_zone_of_device_ops - scallbacks for handling DT based zones
 289  *
 290  * Mandatory:
 291  * @get_temp: a pointer to a function that reads the sensor temperature.
 292  *
 293  * Optional:
 294  * @get_trend: a pointer to a function that reads the sensor temperature trend.
 295  * @set_trips: a pointer to a function that sets a temperature window. When
 296  *             this window is left the driver must inform the thermal core via
 297  *             thermal_zone_device_update.
 298  * @set_emul_temp: a pointer to a function that sets sensor emulated
 299  *                 temperature.
 300  * @set_trip_temp: a pointer to a function that sets the trip temperature on
 301  *                 hardware.
 302  */
 303 struct thermal_zone_of_device_ops {
 304         int (*get_temp)(void *, int *);
 305         int (*get_trend)(void *, int, enum thermal_trend *);
 306         int (*set_trips)(void *, int, int);
 307         int (*set_emul_temp)(void *, int);
 308         int (*set_trip_temp)(void *, int, int);
 309 };
 310
 311 /* Function declarations */
 312 #ifdef CONFIG_THERMAL_OF
 313 int thermal_zone_of_get_sensor_id(struct device_node *tz_np,
 314                                   struct device_node *sensor_np,
 315                                   u32 *id);
 316 struct thermal_zone_device *
 317 thermal_zone_of_sensor_register(struct device *dev, int id, void *data,
 318                                 const struct thermal_zone_of_device_ops *ops);
 319 void thermal_zone_of_sensor_unregister(struct device *dev,
 320                                        struct thermal_zone_device *tz);
 321 struct thermal_zone_device *devm_thermal_zone_of_sensor_register(
 322                 struct device *dev, int id, void *data,
 323                 const struct thermal_zone_of_device_ops *ops);
 324 void devm_thermal_zone_of_sensor_unregister(struct device *dev,
 325                                             struct thermal_zone_device *tz);
 326 #else
 327
 328 static inline int thermal_zone_of_get_sensor_id(struct device_node *tz_np,
 329                                          struct device_node *sensor_np,
 330                                          u32 *id)
 331 {
 332         return -ENOENT;
 333 }
 334 static inline struct thermal_zone_device *
 335 thermal_zone_of_sensor_register(struct device *dev, int id, void *data,
 336                                 const struct thermal_zone_of_device_ops *ops)
 337 {
 338         return ERR_PTR(-ENODEV);
 339 }
 340
 341 static inline
 342 void thermal_zone_of_sensor_unregister(struct device *dev,
 343                                        struct thermal_zone_device *tz)
 344 {
 345 }
 346
 347 static inline struct thermal_zone_device *devm_thermal_zone_of_sensor_register(
 348                 struct device *dev, int id, void *data,
 349                 const struct thermal_zone_of_device_ops *ops)
 350 {
 351         return ERR_PTR(-ENODEV);
 352 }
 353
 354 static inline
 355 void devm_thermal_zone_of_sensor_unregister(struct device *dev,
 356                                             struct thermal_zone_device *tz)
 357 {
 358 }
 359
 360 #endif
 361
 362 #ifdef CONFIG_THERMAL
 363 struct thermal_zone_device *thermal_zone_device_register(const char *, int, int,
 364                 void *, struct thermal_zone_device_ops *,
 365                 struct thermal_zone_params *, int, int);
 366 void thermal_zone_device_unregister(struct thermal_zone_device *);
 367
 368 int thermal_zone_bind_cooling_device(struct thermal_zone_device *, int,
 369                                      struct thermal_cooling_device *,
 370                                      unsigned long, unsigned long,
 371                                      unsigned int);
 372 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
 373                                        struct thermal_cooling_device *);
 374 void thermal_zone_device_update(struct thermal_zone_device *,
 375                                 enum thermal_notify_event);
 376
 377 struct thermal_cooling_device *thermal_cooling_device_register(const char *,
 378                 void *, const struct thermal_cooling_device_ops *);
 379 struct thermal_cooling_device *
 380 thermal_of_cooling_device_register(struct device_node *np, const char *, void *,
 381                                    const struct thermal_cooling_device_ops *);
 382 struct thermal_cooling_device *
 383 devm_thermal_of_cooling_device_register(struct device *dev,
 384                                 struct device_node *np,
 385                                 char *type, void *devdata,
 386                                 const struct thermal_cooling_device_ops *ops);
 387 void thermal_cooling_device_unregister(struct thermal_cooling_device *);
 388 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name);
 389 int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp);
 390 int thermal_zone_get_slope(struct thermal_zone_device *tz);
 391 int thermal_zone_get_offset(struct thermal_zone_device *tz);
 392
 393 int thermal_zone_device_enable(struct thermal_zone_device *tz);
 394 int thermal_zone_device_disable(struct thermal_zone_device *tz);
 395 void thermal_zone_device_critical(struct thermal_zone_device *tz);
 396 #else
 397 static inline struct thermal_zone_device *thermal_zone_device_register(
 398         const char *type, int trips, int mask, void *devdata,
 399         struct thermal_zone_device_ops *ops,
 400         struct thermal_zone_params *tzp,
 401         int passive_delay, int polling_delay)
 402 { return ERR_PTR(-ENODEV); }
 403 static inline void thermal_zone_device_unregister(
 404         struct thermal_zone_device *tz)
 405 { }
 406 static inline struct thermal_cooling_device *
 407 thermal_cooling_device_register(char *type, void *devdata,
 408         const struct thermal_cooling_device_ops *ops)
 409 { return ERR_PTR(-ENODEV); }
 410 static inline struct thermal_cooling_device *
 411 thermal_of_cooling_device_register(struct device_node *np,
 412         char *type, void *devdata, const struct thermal_cooling_device_ops *ops)
 413 { return ERR_PTR(-ENODEV); }
 414 static inline struct thermal_cooling_device *
 415 devm_thermal_of_cooling_device_register(struct device *dev,
 416                                 struct device_node *np,
 417                                 char *type, void *devdata,
 418                                 const struct thermal_cooling_device_ops *ops)
 419 {
 420         return ERR_PTR(-ENODEV);
 421 }
 422 static inline void thermal_cooling_device_unregister(
 423         struct thermal_cooling_device *cdev)
 424 { }
 425 static inline struct thermal_zone_device *thermal_zone_get_zone_by_name(
 426                 const char *name)
 427 { return ERR_PTR(-ENODEV); }
 428 static inline int thermal_zone_get_temp(
 429                 struct thermal_zone_device *tz, int *temp)
 430 { return -ENODEV; }
 431 static inline int thermal_zone_get_slope(
 432                 struct thermal_zone_device *tz)
 433 { return -ENODEV; }
 434 static inline int thermal_zone_get_offset(
 435                 struct thermal_zone_device *tz)
 436 { return -ENODEV; }
 437
 438 static inline int thermal_zone_device_enable(struct thermal_zone_device *tz)
 439 { return -ENODEV; }
 440
 441 static inline int thermal_zone_device_disable(struct thermal_zone_device *tz)
 442 { return -ENODEV; }
 443 #endif /* CONFIG_THERMAL */
 444
 445 #endif /* __THERMAL_H__ */