xref: /openbmc/linux/include/linux/power_supply.h (revision a2cab953)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  *  Universal power supply monitor class
4  *
5  *  Copyright © 2007  Anton Vorontsov <cbou@mail.ru>
6  *  Copyright © 2004  Szabolcs Gyurko
7  *  Copyright © 2003  Ian Molton <spyro@f2s.com>
8  *
9  *  Modified: 2004, Oct     Szabolcs Gyurko
10  */
11 
12 #ifndef __LINUX_POWER_SUPPLY_H__
13 #define __LINUX_POWER_SUPPLY_H__
14 
15 #include <linux/device.h>
16 #include <linux/workqueue.h>
17 #include <linux/leds.h>
18 #include <linux/spinlock.h>
19 #include <linux/notifier.h>
20 
21 /*
22  * All voltages, currents, charges, energies, time and temperatures in uV,
23  * µA, µAh, µWh, seconds and tenths of degree Celsius unless otherwise
24  * stated. It's driver's job to convert its raw values to units in which
25  * this class operates.
26  */
27 
28 /*
29  * For systems where the charger determines the maximum battery capacity
30  * the min and max fields should be used to present these values to user
31  * space. Unused/unknown fields will not appear in sysfs.
32  */
33 
34 enum {
35 	POWER_SUPPLY_STATUS_UNKNOWN = 0,
36 	POWER_SUPPLY_STATUS_CHARGING,
37 	POWER_SUPPLY_STATUS_DISCHARGING,
38 	POWER_SUPPLY_STATUS_NOT_CHARGING,
39 	POWER_SUPPLY_STATUS_FULL,
40 };
41 
42 /* What algorithm is the charger using? */
43 enum {
44 	POWER_SUPPLY_CHARGE_TYPE_UNKNOWN = 0,
45 	POWER_SUPPLY_CHARGE_TYPE_NONE,
46 	POWER_SUPPLY_CHARGE_TYPE_TRICKLE,	/* slow speed */
47 	POWER_SUPPLY_CHARGE_TYPE_FAST,		/* fast speed */
48 	POWER_SUPPLY_CHARGE_TYPE_STANDARD,	/* normal speed */
49 	POWER_SUPPLY_CHARGE_TYPE_ADAPTIVE,	/* dynamically adjusted speed */
50 	POWER_SUPPLY_CHARGE_TYPE_CUSTOM,	/* use CHARGE_CONTROL_* props */
51 	POWER_SUPPLY_CHARGE_TYPE_LONGLIFE,	/* slow speed, longer life */
52 	POWER_SUPPLY_CHARGE_TYPE_BYPASS,	/* bypassing the charger */
53 };
54 
55 enum {
56 	POWER_SUPPLY_HEALTH_UNKNOWN = 0,
57 	POWER_SUPPLY_HEALTH_GOOD,
58 	POWER_SUPPLY_HEALTH_OVERHEAT,
59 	POWER_SUPPLY_HEALTH_DEAD,
60 	POWER_SUPPLY_HEALTH_OVERVOLTAGE,
61 	POWER_SUPPLY_HEALTH_UNSPEC_FAILURE,
62 	POWER_SUPPLY_HEALTH_COLD,
63 	POWER_SUPPLY_HEALTH_WATCHDOG_TIMER_EXPIRE,
64 	POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE,
65 	POWER_SUPPLY_HEALTH_OVERCURRENT,
66 	POWER_SUPPLY_HEALTH_CALIBRATION_REQUIRED,
67 	POWER_SUPPLY_HEALTH_WARM,
68 	POWER_SUPPLY_HEALTH_COOL,
69 	POWER_SUPPLY_HEALTH_HOT,
70 	POWER_SUPPLY_HEALTH_NO_BATTERY,
71 };
72 
73 enum {
74 	POWER_SUPPLY_TECHNOLOGY_UNKNOWN = 0,
75 	POWER_SUPPLY_TECHNOLOGY_NiMH,
76 	POWER_SUPPLY_TECHNOLOGY_LION,
77 	POWER_SUPPLY_TECHNOLOGY_LIPO,
78 	POWER_SUPPLY_TECHNOLOGY_LiFe,
79 	POWER_SUPPLY_TECHNOLOGY_NiCd,
80 	POWER_SUPPLY_TECHNOLOGY_LiMn,
81 };
82 
83 enum {
84 	POWER_SUPPLY_CAPACITY_LEVEL_UNKNOWN = 0,
85 	POWER_SUPPLY_CAPACITY_LEVEL_CRITICAL,
86 	POWER_SUPPLY_CAPACITY_LEVEL_LOW,
87 	POWER_SUPPLY_CAPACITY_LEVEL_NORMAL,
88 	POWER_SUPPLY_CAPACITY_LEVEL_HIGH,
89 	POWER_SUPPLY_CAPACITY_LEVEL_FULL,
90 };
91 
92 enum {
93 	POWER_SUPPLY_SCOPE_UNKNOWN = 0,
94 	POWER_SUPPLY_SCOPE_SYSTEM,
95 	POWER_SUPPLY_SCOPE_DEVICE,
96 };
97 
98 enum power_supply_property {
99 	/* Properties of type `int' */
100 	POWER_SUPPLY_PROP_STATUS = 0,
101 	POWER_SUPPLY_PROP_CHARGE_TYPE,
102 	POWER_SUPPLY_PROP_HEALTH,
103 	POWER_SUPPLY_PROP_PRESENT,
104 	POWER_SUPPLY_PROP_ONLINE,
105 	POWER_SUPPLY_PROP_AUTHENTIC,
106 	POWER_SUPPLY_PROP_TECHNOLOGY,
107 	POWER_SUPPLY_PROP_CYCLE_COUNT,
108 	POWER_SUPPLY_PROP_VOLTAGE_MAX,
109 	POWER_SUPPLY_PROP_VOLTAGE_MIN,
110 	POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
111 	POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
112 	POWER_SUPPLY_PROP_VOLTAGE_NOW,
113 	POWER_SUPPLY_PROP_VOLTAGE_AVG,
114 	POWER_SUPPLY_PROP_VOLTAGE_OCV,
115 	POWER_SUPPLY_PROP_VOLTAGE_BOOT,
116 	POWER_SUPPLY_PROP_CURRENT_MAX,
117 	POWER_SUPPLY_PROP_CURRENT_NOW,
118 	POWER_SUPPLY_PROP_CURRENT_AVG,
119 	POWER_SUPPLY_PROP_CURRENT_BOOT,
120 	POWER_SUPPLY_PROP_POWER_NOW,
121 	POWER_SUPPLY_PROP_POWER_AVG,
122 	POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
123 	POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN,
124 	POWER_SUPPLY_PROP_CHARGE_FULL,
125 	POWER_SUPPLY_PROP_CHARGE_EMPTY,
126 	POWER_SUPPLY_PROP_CHARGE_NOW,
127 	POWER_SUPPLY_PROP_CHARGE_AVG,
128 	POWER_SUPPLY_PROP_CHARGE_COUNTER,
129 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,
130 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,
131 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,
132 	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,
133 	POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT,
134 	POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT_MAX,
135 	POWER_SUPPLY_PROP_CHARGE_CONTROL_START_THRESHOLD, /* in percents! */
136 	POWER_SUPPLY_PROP_CHARGE_CONTROL_END_THRESHOLD, /* in percents! */
137 	POWER_SUPPLY_PROP_CHARGE_BEHAVIOUR,
138 	POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT,
139 	POWER_SUPPLY_PROP_INPUT_VOLTAGE_LIMIT,
140 	POWER_SUPPLY_PROP_INPUT_POWER_LIMIT,
141 	POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN,
142 	POWER_SUPPLY_PROP_ENERGY_EMPTY_DESIGN,
143 	POWER_SUPPLY_PROP_ENERGY_FULL,
144 	POWER_SUPPLY_PROP_ENERGY_EMPTY,
145 	POWER_SUPPLY_PROP_ENERGY_NOW,
146 	POWER_SUPPLY_PROP_ENERGY_AVG,
147 	POWER_SUPPLY_PROP_CAPACITY, /* in percents! */
148 	POWER_SUPPLY_PROP_CAPACITY_ALERT_MIN, /* in percents! */
149 	POWER_SUPPLY_PROP_CAPACITY_ALERT_MAX, /* in percents! */
150 	POWER_SUPPLY_PROP_CAPACITY_ERROR_MARGIN, /* in percents! */
151 	POWER_SUPPLY_PROP_CAPACITY_LEVEL,
152 	POWER_SUPPLY_PROP_TEMP,
153 	POWER_SUPPLY_PROP_TEMP_MAX,
154 	POWER_SUPPLY_PROP_TEMP_MIN,
155 	POWER_SUPPLY_PROP_TEMP_ALERT_MIN,
156 	POWER_SUPPLY_PROP_TEMP_ALERT_MAX,
157 	POWER_SUPPLY_PROP_TEMP_AMBIENT,
158 	POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MIN,
159 	POWER_SUPPLY_PROP_TEMP_AMBIENT_ALERT_MAX,
160 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
161 	POWER_SUPPLY_PROP_TIME_TO_EMPTY_AVG,
162 	POWER_SUPPLY_PROP_TIME_TO_FULL_NOW,
163 	POWER_SUPPLY_PROP_TIME_TO_FULL_AVG,
164 	POWER_SUPPLY_PROP_TYPE, /* use power_supply.type instead */
165 	POWER_SUPPLY_PROP_USB_TYPE,
166 	POWER_SUPPLY_PROP_SCOPE,
167 	POWER_SUPPLY_PROP_PRECHARGE_CURRENT,
168 	POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT,
169 	POWER_SUPPLY_PROP_CALIBRATE,
170 	POWER_SUPPLY_PROP_MANUFACTURE_YEAR,
171 	POWER_SUPPLY_PROP_MANUFACTURE_MONTH,
172 	POWER_SUPPLY_PROP_MANUFACTURE_DAY,
173 	/* Properties of type `const char *' */
174 	POWER_SUPPLY_PROP_MODEL_NAME,
175 	POWER_SUPPLY_PROP_MANUFACTURER,
176 	POWER_SUPPLY_PROP_SERIAL_NUMBER,
177 };
178 
179 enum power_supply_type {
180 	POWER_SUPPLY_TYPE_UNKNOWN = 0,
181 	POWER_SUPPLY_TYPE_BATTERY,
182 	POWER_SUPPLY_TYPE_UPS,
183 	POWER_SUPPLY_TYPE_MAINS,
184 	POWER_SUPPLY_TYPE_USB,			/* Standard Downstream Port */
185 	POWER_SUPPLY_TYPE_USB_DCP,		/* Dedicated Charging Port */
186 	POWER_SUPPLY_TYPE_USB_CDP,		/* Charging Downstream Port */
187 	POWER_SUPPLY_TYPE_USB_ACA,		/* Accessory Charger Adapters */
188 	POWER_SUPPLY_TYPE_USB_TYPE_C,		/* Type C Port */
189 	POWER_SUPPLY_TYPE_USB_PD,		/* Power Delivery Port */
190 	POWER_SUPPLY_TYPE_USB_PD_DRP,		/* PD Dual Role Port */
191 	POWER_SUPPLY_TYPE_APPLE_BRICK_ID,	/* Apple Charging Method */
192 	POWER_SUPPLY_TYPE_WIRELESS,		/* Wireless */
193 };
194 
195 enum power_supply_usb_type {
196 	POWER_SUPPLY_USB_TYPE_UNKNOWN = 0,
197 	POWER_SUPPLY_USB_TYPE_SDP,		/* Standard Downstream Port */
198 	POWER_SUPPLY_USB_TYPE_DCP,		/* Dedicated Charging Port */
199 	POWER_SUPPLY_USB_TYPE_CDP,		/* Charging Downstream Port */
200 	POWER_SUPPLY_USB_TYPE_ACA,		/* Accessory Charger Adapters */
201 	POWER_SUPPLY_USB_TYPE_C,		/* Type C Port */
202 	POWER_SUPPLY_USB_TYPE_PD,		/* Power Delivery Port */
203 	POWER_SUPPLY_USB_TYPE_PD_DRP,		/* PD Dual Role Port */
204 	POWER_SUPPLY_USB_TYPE_PD_PPS,		/* PD Programmable Power Supply */
205 	POWER_SUPPLY_USB_TYPE_APPLE_BRICK_ID,	/* Apple Charging Method */
206 };
207 
208 enum power_supply_charge_behaviour {
209 	POWER_SUPPLY_CHARGE_BEHAVIOUR_AUTO = 0,
210 	POWER_SUPPLY_CHARGE_BEHAVIOUR_INHIBIT_CHARGE,
211 	POWER_SUPPLY_CHARGE_BEHAVIOUR_FORCE_DISCHARGE,
212 };
213 
214 enum power_supply_notifier_events {
215 	PSY_EVENT_PROP_CHANGED,
216 };
217 
218 union power_supply_propval {
219 	int intval;
220 	const char *strval;
221 };
222 
223 struct device_node;
224 struct power_supply;
225 
226 /* Run-time specific power supply configuration */
227 struct power_supply_config {
228 	struct device_node *of_node;
229 	struct fwnode_handle *fwnode;
230 
231 	/* Driver private data */
232 	void *drv_data;
233 
234 	/* Device specific sysfs attributes */
235 	const struct attribute_group **attr_grp;
236 
237 	char **supplied_to;
238 	size_t num_supplicants;
239 };
240 
241 /* Description of power supply */
242 struct power_supply_desc {
243 	const char *name;
244 	enum power_supply_type type;
245 	const enum power_supply_usb_type *usb_types;
246 	size_t num_usb_types;
247 	const enum power_supply_property *properties;
248 	size_t num_properties;
249 
250 	/*
251 	 * Functions for drivers implementing power supply class.
252 	 * These shouldn't be called directly by other drivers for accessing
253 	 * this power supply. Instead use power_supply_*() functions (for
254 	 * example power_supply_get_property()).
255 	 */
256 	int (*get_property)(struct power_supply *psy,
257 			    enum power_supply_property psp,
258 			    union power_supply_propval *val);
259 	int (*set_property)(struct power_supply *psy,
260 			    enum power_supply_property psp,
261 			    const union power_supply_propval *val);
262 	/*
263 	 * property_is_writeable() will be called during registration
264 	 * of power supply. If this happens during device probe then it must
265 	 * not access internal data of device (because probe did not end).
266 	 */
267 	int (*property_is_writeable)(struct power_supply *psy,
268 				     enum power_supply_property psp);
269 	void (*external_power_changed)(struct power_supply *psy);
270 	void (*set_charged)(struct power_supply *psy);
271 
272 	/*
273 	 * Set if thermal zone should not be created for this power supply.
274 	 * For example for virtual supplies forwarding calls to actual
275 	 * sensors or other supplies.
276 	 */
277 	bool no_thermal;
278 	/* For APM emulation, think legacy userspace. */
279 	int use_for_apm;
280 };
281 
282 struct power_supply {
283 	const struct power_supply_desc *desc;
284 
285 	char **supplied_to;
286 	size_t num_supplicants;
287 
288 	char **supplied_from;
289 	size_t num_supplies;
290 	struct device_node *of_node;
291 
292 	/* Driver private data */
293 	void *drv_data;
294 
295 	/* private */
296 	struct device dev;
297 	struct work_struct changed_work;
298 	struct delayed_work deferred_register_work;
299 	spinlock_t changed_lock;
300 	bool changed;
301 	bool initialized;
302 	bool removing;
303 	atomic_t use_cnt;
304 #ifdef CONFIG_THERMAL
305 	struct thermal_zone_device *tzd;
306 	struct thermal_cooling_device *tcd;
307 #endif
308 
309 #ifdef CONFIG_LEDS_TRIGGERS
310 	struct led_trigger *charging_full_trig;
311 	char *charging_full_trig_name;
312 	struct led_trigger *charging_trig;
313 	char *charging_trig_name;
314 	struct led_trigger *full_trig;
315 	char *full_trig_name;
316 	struct led_trigger *online_trig;
317 	char *online_trig_name;
318 	struct led_trigger *charging_blink_full_solid_trig;
319 	char *charging_blink_full_solid_trig_name;
320 #endif
321 };
322 
323 /*
324  * This is recommended structure to specify static power supply parameters.
325  * Generic one, parametrizable for different power supplies. Power supply
326  * class itself does not use it, but that's what implementing most platform
327  * drivers, should try reuse for consistency.
328  */
329 
330 struct power_supply_info {
331 	const char *name;
332 	int technology;
333 	int voltage_max_design;
334 	int voltage_min_design;
335 	int charge_full_design;
336 	int charge_empty_design;
337 	int energy_full_design;
338 	int energy_empty_design;
339 	int use_for_apm;
340 };
341 
342 struct power_supply_battery_ocv_table {
343 	int ocv;	/* microVolts */
344 	int capacity;	/* percent */
345 };
346 
347 struct power_supply_resistance_temp_table {
348 	int temp;	/* celsius */
349 	int resistance;	/* internal resistance percent */
350 };
351 
352 struct power_supply_vbat_ri_table {
353 	int vbat_uv;	/* Battery voltage in microvolt */
354 	int ri_uohm;	/* Internal resistance in microohm */
355 };
356 
357 /**
358  * struct power_supply_maintenance_charge_table - setting for maintenace charging
359  * @charge_current_max_ua: maintenance charging current that is used to keep
360  *   the charge of the battery full as current is consumed after full charging.
361  *   The corresponding charge_voltage_max_uv is used as a safeguard: when we
362  *   reach this voltage the maintenance charging current is turned off. It is
363  *   turned back on if we fall below this voltage.
364  * @charge_voltage_max_uv: maintenance charging voltage that is usually a bit
365  *   lower than the constant_charge_voltage_max_uv. We can apply this settings
366  *   charge_current_max_ua until we get back up to this voltage.
367  * @safety_timer_minutes: maintenance charging safety timer, with an expiry
368  *   time in minutes. We will only use maintenance charging in this setting
369  *   for a certain amount of time, then we will first move to the next
370  *   maintenance charge current and voltage pair in respective array and wait
371  *   for the next safety timer timeout, or, if we reached the last maintencance
372  *   charging setting, disable charging until we reach
373  *   charge_restart_voltage_uv and restart ordinary CC/CV charging from there.
374  *   These timers should be chosen to align with the typical discharge curve
375  *   for the battery.
376  *
377  * Ordinary CC/CV charging will stop charging when the charge current goes
378  * below charge_term_current_ua, and then restart it (if the device is still
379  * plugged into the charger) at charge_restart_voltage_uv. This happens in most
380  * consumer products because the power usage while connected to a charger is
381  * not zero, and devices are not manufactured to draw power directly from the
382  * charger: instead they will at all times dissipate the battery a little, like
383  * the power used in standby mode. This will over time give a charge graph
384  * such as this:
385  *
386  * Energy
387  *  ^      ...        ...      ...      ...      ...      ...      ...
388  *  |    .   .       .  .     .  .     .  .     .  .     .  .     .
389  *  |  ..     .   ..     .  ..    .  ..    .  ..    .  ..    .  ..
390  *  |.          ..        ..       ..       ..       ..       ..
391  *  +-------------------------------------------------------------------> t
392  *
393  * Practically this means that the Li-ions are wandering back and forth in the
394  * battery and this causes degeneration of the battery anode and cathode.
395  * To prolong the life of the battery, maintenance charging is applied after
396  * reaching charge_term_current_ua to hold up the charge in the battery while
397  * consuming power, thus lowering the wear on the battery:
398  *
399  * Energy
400  *  ^      .......................................
401  *  |    .                                        ......................
402  *  |  ..
403  *  |.
404  *  +-------------------------------------------------------------------> t
405  *
406  * Maintenance charging uses the voltages from this table: a table of settings
407  * is traversed using a slightly lower current and voltage than what is used for
408  * CC/CV charging. The maintenance charging will for safety reasons not go on
409  * indefinately: we lower the current and voltage with successive maintenance
410  * settings, then disable charging completely after we reach the last one,
411  * and after that we do not restart charging until we reach
412  * charge_restart_voltage_uv (see struct power_supply_battery_info) and restart
413  * ordinary CC/CV charging from there.
414  *
415  * As an example, a Samsung EB425161LA Lithium-Ion battery is CC/CV charged
416  * at 900mA to 4340mV, then maintenance charged at 600mA and 4150mV for up to
417  * 60 hours, then maintenance charged at 600mA and 4100mV for up to 200 hours.
418  * After this the charge cycle is restarted waiting for
419  * charge_restart_voltage_uv.
420  *
421  * For most mobile electronics this type of maintenance charging is enough for
422  * the user to disconnect the device and make use of it before both maintenance
423  * charging cycles are complete, if the current and voltage has been chosen
424  * appropriately. These need to be determined from battery discharge curves
425  * and expected standby current.
426  *
427  * If the voltage anyway drops to charge_restart_voltage_uv during maintenance
428  * charging, ordinary CC/CV charging is restarted. This can happen if the
429  * device is e.g. actively used during charging, so more current is drawn than
430  * the expected stand-by current. Also overvoltage protection will be applied
431  * as usual.
432  */
433 struct power_supply_maintenance_charge_table {
434 	int charge_current_max_ua;
435 	int charge_voltage_max_uv;
436 	int charge_safety_timer_minutes;
437 };
438 
439 #define POWER_SUPPLY_OCV_TEMP_MAX 20
440 
441 /**
442  * struct power_supply_battery_info - information about batteries
443  * @technology: from the POWER_SUPPLY_TECHNOLOGY_* enum
444  * @energy_full_design_uwh: energy content when fully charged in microwatt
445  *   hours
446  * @charge_full_design_uah: charge content when fully charged in microampere
447  *   hours
448  * @voltage_min_design_uv: minimum voltage across the poles when the battery
449  *   is at minimum voltage level in microvolts. If the voltage drops below this
450  *   level the battery will need precharging when using CC/CV charging.
451  * @voltage_max_design_uv: voltage across the poles when the battery is fully
452  *   charged in microvolts. This is the "nominal voltage" i.e. the voltage
453  *   printed on the label of the battery.
454  * @tricklecharge_current_ua: the tricklecharge current used when trickle
455  *   charging the battery in microamperes. This is the charging phase when the
456  *   battery is completely empty and we need to carefully trickle in some
457  *   charge until we reach the precharging voltage.
458  * @precharge_current_ua: current to use in the precharge phase in microamperes,
459  *   the precharge rate is limited by limiting the current to this value.
460  * @precharge_voltage_max_uv: the maximum voltage allowed when precharging in
461  *   microvolts. When we pass this voltage we will nominally switch over to the
462  *   CC (constant current) charging phase defined by constant_charge_current_ua
463  *   and constant_charge_voltage_max_uv.
464  * @charge_term_current_ua: when the current in the CV (constant voltage)
465  *   charging phase drops below this value in microamperes the charging will
466  *   terminate completely and not restart until the voltage over the battery
467  *   poles reach charge_restart_voltage_uv unless we use maintenance charging.
468  * @charge_restart_voltage_uv: when the battery has been fully charged by
469  *   CC/CV charging and charging has been disabled, and the voltage subsequently
470  *   drops below this value in microvolts, the charging will be restarted
471  *   (typically using CV charging).
472  * @overvoltage_limit_uv: If the voltage exceeds the nominal voltage
473  *   voltage_max_design_uv and we reach this voltage level, all charging must
474  *   stop and emergency procedures take place, such as shutting down the system
475  *   in some cases.
476  * @constant_charge_current_max_ua: current in microamperes to use in the CC
477  *   (constant current) charging phase. The charging rate is limited
478  *   by this current. This is the main charging phase and as the current is
479  *   constant into the battery the voltage slowly ascends to
480  *   constant_charge_voltage_max_uv.
481  * @constant_charge_voltage_max_uv: voltage in microvolts signifying the end of
482  *   the CC (constant current) charging phase and the beginning of the CV
483  *   (constant voltage) charging phase.
484  * @maintenance_charge: an array of maintenance charging settings to be used
485  *   after the main CC/CV charging phase is complete.
486  * @maintenance_charge_size: the number of maintenance charging settings in
487  *   maintenance_charge.
488  * @alert_low_temp_charge_current_ua: The charging current to use if the battery
489  *   enters low alert temperature, i.e. if the internal temperature is between
490  *   temp_alert_min and temp_min. No matter the charging phase, this
491  *   and alert_high_temp_charge_voltage_uv will be applied.
492  * @alert_low_temp_charge_voltage_uv: Same as alert_low_temp_charge_current_ua,
493  *   but for the charging voltage.
494  * @alert_high_temp_charge_current_ua: The charging current to use if the
495  *   battery enters high alert temperature, i.e. if the internal temperature is
496  *   between temp_alert_max and temp_max. No matter the charging phase, this
497  *   and alert_high_temp_charge_voltage_uv will be applied, usually lowering
498  *   the charging current as an evasive manouver.
499  * @alert_high_temp_charge_voltage_uv: Same as
500  *   alert_high_temp_charge_current_ua, but for the charging voltage.
501  * @factory_internal_resistance_uohm: the internal resistance of the battery
502  *   at fabrication time, expressed in microohms. This resistance will vary
503  *   depending on the lifetime and charge of the battery, so this is just a
504  *   nominal ballpark figure. This internal resistance is given for the state
505  *   when the battery is discharging.
506  * @factory_internal_resistance_charging_uohm: the internal resistance of the
507  *   battery at fabrication time while charging, expressed in microohms.
508  *   The charging process will affect the internal resistance of the battery
509  *   so this value provides a better resistance under these circumstances.
510  *   This resistance will vary depending on the lifetime and charge of the
511  *   battery, so this is just a nominal ballpark figure.
512  * @ocv_temp: array indicating the open circuit voltage (OCV) capacity
513  *   temperature indices. This is an array of temperatures in degrees Celsius
514  *   indicating which capacity table to use for a certain temperature, since
515  *   the capacity for reasons of chemistry will be different at different
516  *   temperatures. Determining capacity is a multivariate problem and the
517  *   temperature is the first variable we determine.
518  * @temp_ambient_alert_min: the battery will go outside of operating conditions
519  *   when the ambient temperature goes below this temperature in degrees
520  *   Celsius.
521  * @temp_ambient_alert_max: the battery will go outside of operating conditions
522  *   when the ambient temperature goes above this temperature in degrees
523  *   Celsius.
524  * @temp_alert_min: the battery should issue an alert if the internal
525  *   temperature goes below this temperature in degrees Celsius.
526  * @temp_alert_max: the battery should issue an alert if the internal
527  *   temperature goes above this temperature in degrees Celsius.
528  * @temp_min: the battery will go outside of operating conditions when
529  *   the internal temperature goes below this temperature in degrees Celsius.
530  *   Normally this means the system should shut down.
531  * @temp_max: the battery will go outside of operating conditions when
532  *   the internal temperature goes above this temperature in degrees Celsius.
533  *   Normally this means the system should shut down.
534  * @ocv_table: for each entry in ocv_temp there is a corresponding entry in
535  *   ocv_table and a size for each entry in ocv_table_size. These arrays
536  *   determine the capacity in percent in relation to the voltage in microvolts
537  *   at the indexed temperature.
538  * @ocv_table_size: for each entry in ocv_temp this array is giving the size of
539  *   each entry in the array of capacity arrays in ocv_table.
540  * @resist_table: this is a table that correlates a battery temperature to the
541  *   expected internal resistance at this temperature. The resistance is given
542  *   as a percentage of factory_internal_resistance_uohm. Knowing the
543  *   resistance of the battery is usually necessary for calculating the open
544  *   circuit voltage (OCV) that is then used with the ocv_table to calculate
545  *   the capacity of the battery. The resist_table must be ordered descending
546  *   by temperature: highest temperature with lowest resistance first, lowest
547  *   temperature with highest resistance last.
548  * @resist_table_size: the number of items in the resist_table.
549  * @vbat2ri_discharging: this is a table that correlates Battery voltage (VBAT)
550  *   to internal resistance (Ri). The resistance is given in microohm for the
551  *   corresponding voltage in microvolts. The internal resistance is used to
552  *   determine the open circuit voltage so that we can determine the capacity
553  *   of the battery. These voltages to resistance tables apply when the battery
554  *   is discharging. The table must be ordered descending by voltage: highest
555  *   voltage first.
556  * @vbat2ri_discharging_size: the number of items in the vbat2ri_discharging
557  *   table.
558  * @vbat2ri_charging: same function as vbat2ri_discharging but for the state
559  *   when the battery is charging. Being under charge changes the battery's
560  *   internal resistance characteristics so a separate table is needed.*
561  *   The table must be ordered descending by voltage: highest voltage first.
562  * @vbat2ri_charging_size: the number of items in the vbat2ri_charging
563  *   table.
564  * @bti_resistance_ohm: The Battery Type Indicator (BIT) nominal resistance
565  *   in ohms for this battery, if an identification resistor is mounted
566  *   between a third battery terminal and ground. This scheme is used by a lot
567  *   of mobile device batteries.
568  * @bti_resistance_tolerance: The tolerance in percent of the BTI resistance,
569  *   for example 10 for +/- 10%, if the bti_resistance is set to 7000 and the
570  *   tolerance is 10% we will detect a proper battery if the BTI resistance
571  *   is between 6300 and 7700 Ohm.
572  *
573  * This is the recommended struct to manage static battery parameters,
574  * populated by power_supply_get_battery_info(). Most platform drivers should
575  * use these for consistency.
576  *
577  * Its field names must correspond to elements in enum power_supply_property.
578  * The default field value is -EINVAL or NULL for pointers.
579  *
580  * CC/CV CHARGING:
581  *
582  * The charging parameters here assume a CC/CV charging scheme. This method
583  * is most common with Lithium Ion batteries (other methods are possible) and
584  * looks as follows:
585  *
586  * ^ Battery voltage
587  * |                                               --- overvoltage_limit_uv
588  * |
589  * |                    ...................................................
590  * |                 .. constant_charge_voltage_max_uv
591  * |              ..
592  * |             .
593  * |            .
594  * |           .
595  * |          .
596  * |         .
597  * |     .. precharge_voltage_max_uv
598  * |  ..
599  * |. (trickle charging)
600  * +------------------------------------------------------------------> time
601  *
602  * ^ Current into the battery
603  * |
604  * |      ............. constant_charge_current_max_ua
605  * |      .            .
606  * |      .             .
607  * |      .              .
608  * |      .               .
609  * |      .                ..
610  * |      .                  ....
611  * |      .                       .....
612  * |    ... precharge_current_ua       .......  charge_term_current_ua
613  * |    .                                    .
614  * |    .                                    .
615  * |.... tricklecharge_current_ua            .
616  * |                                         .
617  * +-----------------------------------------------------------------> time
618  *
619  * These diagrams are synchronized on time and the voltage and current
620  * follow each other.
621  *
622  * With CC/CV charging commence over time like this for an empty battery:
623  *
624  * 1. When the battery is completely empty it may need to be charged with
625  *    an especially small current so that electrons just "trickle in",
626  *    this is the tricklecharge_current_ua.
627  *
628  * 2. Next a small initial pre-charge current (precharge_current_ua)
629  *    is applied if the voltage is below precharge_voltage_max_uv until we
630  *    reach precharge_voltage_max_uv. CAUTION: in some texts this is referred
631  *    to as "trickle charging" but the use in the Linux kernel is different
632  *    see below!
633  *
634  * 3. Then the main charging current is applied, which is called the constant
635  *    current (CC) phase. A current regulator is set up to allow
636  *    constant_charge_current_max_ua of current to flow into the battery.
637  *    The chemical reaction in the battery will make the voltage go up as
638  *    charge goes into the battery. This current is applied until we reach
639  *    the constant_charge_voltage_max_uv voltage.
640  *
641  * 4. At this voltage we switch over to the constant voltage (CV) phase. This
642  *    means we allow current to go into the battery, but we keep the voltage
643  *    fixed. This current will continue to charge the battery while keeping
644  *    the voltage the same. A chemical reaction in the battery goes on
645  *    storing energy without affecting the voltage. Over time the current
646  *    will slowly drop and when we reach charge_term_current_ua we will
647  *    end the constant voltage phase.
648  *
649  * After this the battery is fully charged, and if we do not support maintenance
650  * charging, the charging will not restart until power dissipation makes the
651  * voltage fall so that we reach charge_restart_voltage_uv and at this point
652  * we restart charging at the appropriate phase, usually this will be inside
653  * the CV phase.
654  *
655  * If we support maintenance charging the voltage is however kept high after
656  * the CV phase with a very low current. This is meant to let the same charge
657  * go in for usage while the charger is still connected, mainly for
658  * dissipation for the power consuming entity while connected to the
659  * charger.
660  *
661  * All charging MUST terminate if the overvoltage_limit_uv is ever reached.
662  * Overcharging Lithium Ion cells can be DANGEROUS and lead to fire or
663  * explosions.
664  *
665  * DETERMINING BATTERY CAPACITY:
666  *
667  * Several members of the struct deal with trying to determine the remaining
668  * capacity in the battery, usually as a percentage of charge. In practice
669  * many chargers uses a so-called fuel gauge or coloumb counter that measure
670  * how much charge goes into the battery and how much goes out (+/- leak
671  * consumption). This does not help if we do not know how much capacity the
672  * battery has to begin with, such as when it is first used or was taken out
673  * and charged in a separate charger. Therefore many capacity algorithms use
674  * the open circuit voltage with a look-up table to determine the rough
675  * capacity of the battery. The open circuit voltage can be conceptualized
676  * with an ideal voltage source (V) in series with an internal resistance (Ri)
677  * like this:
678  *
679  *      +-------> IBAT >----------------+
680  *      |                    ^          |
681  *     [ ] Ri                |          |
682  *      |                    | VBAT     |
683  *      o <----------        |          |
684  *     +|           ^        |         [ ] Rload
685  *    .---.         |        |          |
686  *    | V |         | OCV    |          |
687  *    '---'         |        |          |
688  *      |           |        |          |
689  *  GND +-------------------------------+
690  *
691  * If we disconnect the load (here simplified as a fixed resistance Rload)
692  * and measure VBAT with a infinite impedance voltage meter we will get
693  * VBAT = OCV and this assumption is sometimes made even under load, assuming
694  * Rload is insignificant. However this will be of dubious quality because the
695  * load is rarely that small and Ri is strongly nonlinear depending on
696  * temperature and how much capacity is left in the battery due to the
697  * chemistry involved.
698  *
699  * In many practical applications we cannot just disconnect the battery from
700  * the load, so instead we often try to measure the instantaneous IBAT (the
701  * current out from the battery), estimate the Ri and thus calculate the
702  * voltage drop over Ri and compensate like this:
703  *
704  *   OCV = VBAT - (IBAT * Ri)
705  *
706  * The tables vbat2ri_discharging and vbat2ri_charging are used to determine
707  * (by interpolation) the Ri from the VBAT under load. These curves are highly
708  * nonlinear and may need many datapoints but can be found in datasheets for
709  * some batteries. This gives the compensated open circuit voltage (OCV) for
710  * the battery even under load. Using this method will also compensate for
711  * temperature changes in the environment: this will also make the internal
712  * resistance change, and it will affect the VBAT under load, so correlating
713  * VBAT to Ri takes both remaining capacity and temperature into consideration.
714  *
715  * Alternatively a manufacturer can specify how the capacity of the battery
716  * is dependent on the battery temperature which is the main factor affecting
717  * Ri. As we know all checmical reactions are faster when it is warm and slower
718  * when it is cold. You can put in 1500mAh and only get 800mAh out before the
719  * voltage drops too low for example. This effect is also highly nonlinear and
720  * the purpose of the table resist_table: this will take a temperature and
721  * tell us how big percentage of Ri the specified temperature correlates to.
722  * Usually we have 100% of the factory_internal_resistance_uohm at 25 degrees
723  * Celsius.
724  *
725  * The power supply class itself doesn't use this struct as of now.
726  */
727 
728 struct power_supply_battery_info {
729 	unsigned int technology;
730 	int energy_full_design_uwh;
731 	int charge_full_design_uah;
732 	int voltage_min_design_uv;
733 	int voltage_max_design_uv;
734 	int tricklecharge_current_ua;
735 	int precharge_current_ua;
736 	int precharge_voltage_max_uv;
737 	int charge_term_current_ua;
738 	int charge_restart_voltage_uv;
739 	int overvoltage_limit_uv;
740 	int constant_charge_current_max_ua;
741 	int constant_charge_voltage_max_uv;
742 	struct power_supply_maintenance_charge_table *maintenance_charge;
743 	int maintenance_charge_size;
744 	int alert_low_temp_charge_current_ua;
745 	int alert_low_temp_charge_voltage_uv;
746 	int alert_high_temp_charge_current_ua;
747 	int alert_high_temp_charge_voltage_uv;
748 	int factory_internal_resistance_uohm;
749 	int factory_internal_resistance_charging_uohm;
750 	int ocv_temp[POWER_SUPPLY_OCV_TEMP_MAX];
751 	int temp_ambient_alert_min;
752 	int temp_ambient_alert_max;
753 	int temp_alert_min;
754 	int temp_alert_max;
755 	int temp_min;
756 	int temp_max;
757 	struct power_supply_battery_ocv_table *ocv_table[POWER_SUPPLY_OCV_TEMP_MAX];
758 	int ocv_table_size[POWER_SUPPLY_OCV_TEMP_MAX];
759 	struct power_supply_resistance_temp_table *resist_table;
760 	int resist_table_size;
761 	struct power_supply_vbat_ri_table *vbat2ri_discharging;
762 	int vbat2ri_discharging_size;
763 	struct power_supply_vbat_ri_table *vbat2ri_charging;
764 	int vbat2ri_charging_size;
765 	int bti_resistance_ohm;
766 	int bti_resistance_tolerance;
767 };
768 
769 extern struct atomic_notifier_head power_supply_notifier;
770 extern int power_supply_reg_notifier(struct notifier_block *nb);
771 extern void power_supply_unreg_notifier(struct notifier_block *nb);
772 #if IS_ENABLED(CONFIG_POWER_SUPPLY)
773 extern struct power_supply *power_supply_get_by_name(const char *name);
774 extern void power_supply_put(struct power_supply *psy);
775 #else
776 static inline void power_supply_put(struct power_supply *psy) {}
777 static inline struct power_supply *power_supply_get_by_name(const char *name)
778 { return NULL; }
779 #endif
780 #ifdef CONFIG_OF
781 extern struct power_supply *power_supply_get_by_phandle(struct device_node *np,
782 							const char *property);
783 extern struct power_supply *devm_power_supply_get_by_phandle(
784 				    struct device *dev, const char *property);
785 #else /* !CONFIG_OF */
786 static inline struct power_supply *
787 power_supply_get_by_phandle(struct device_node *np, const char *property)
788 { return NULL; }
789 static inline struct power_supply *
790 devm_power_supply_get_by_phandle(struct device *dev, const char *property)
791 { return NULL; }
792 #endif /* CONFIG_OF */
793 
794 extern int power_supply_get_battery_info(struct power_supply *psy,
795 					 struct power_supply_battery_info **info_out);
796 extern void power_supply_put_battery_info(struct power_supply *psy,
797 					  struct power_supply_battery_info *info);
798 extern int power_supply_ocv2cap_simple(struct power_supply_battery_ocv_table *table,
799 				       int table_len, int ocv);
800 extern struct power_supply_battery_ocv_table *
801 power_supply_find_ocv2cap_table(struct power_supply_battery_info *info,
802 				int temp, int *table_len);
803 extern int power_supply_batinfo_ocv2cap(struct power_supply_battery_info *info,
804 					int ocv, int temp);
805 extern int
806 power_supply_temp2resist_simple(struct power_supply_resistance_temp_table *table,
807 				int table_len, int temp);
808 extern int power_supply_vbat2ri(struct power_supply_battery_info *info,
809 				int vbat_uv, bool charging);
810 extern struct power_supply_maintenance_charge_table *
811 power_supply_get_maintenance_charging_setting(struct power_supply_battery_info *info, int index);
812 extern bool power_supply_battery_bti_in_range(struct power_supply_battery_info *info,
813 					      int resistance);
814 extern void power_supply_changed(struct power_supply *psy);
815 extern int power_supply_am_i_supplied(struct power_supply *psy);
816 int power_supply_get_property_from_supplier(struct power_supply *psy,
817 					    enum power_supply_property psp,
818 					    union power_supply_propval *val);
819 extern int power_supply_set_battery_charged(struct power_supply *psy);
820 
821 static inline bool
822 power_supply_supports_maintenance_charging(struct power_supply_battery_info *info)
823 {
824 	struct power_supply_maintenance_charge_table *mt;
825 
826 	mt = power_supply_get_maintenance_charging_setting(info, 0);
827 
828 	return (mt != NULL);
829 }
830 
831 static inline bool
832 power_supply_supports_vbat2ri(struct power_supply_battery_info *info)
833 {
834 	return ((info->vbat2ri_discharging != NULL) &&
835 		info->vbat2ri_discharging_size > 0);
836 }
837 
838 static inline bool
839 power_supply_supports_temp2ri(struct power_supply_battery_info *info)
840 {
841 	return ((info->resist_table != NULL) &&
842 		info->resist_table_size > 0);
843 }
844 
845 #ifdef CONFIG_POWER_SUPPLY
846 extern int power_supply_is_system_supplied(void);
847 #else
848 static inline int power_supply_is_system_supplied(void) { return -ENOSYS; }
849 #endif
850 
851 extern int power_supply_get_property(struct power_supply *psy,
852 			    enum power_supply_property psp,
853 			    union power_supply_propval *val);
854 #if IS_ENABLED(CONFIG_POWER_SUPPLY)
855 extern int power_supply_set_property(struct power_supply *psy,
856 			    enum power_supply_property psp,
857 			    const union power_supply_propval *val);
858 #else
859 static inline int power_supply_set_property(struct power_supply *psy,
860 			    enum power_supply_property psp,
861 			    const union power_supply_propval *val)
862 { return 0; }
863 #endif
864 extern int power_supply_property_is_writeable(struct power_supply *psy,
865 					enum power_supply_property psp);
866 extern void power_supply_external_power_changed(struct power_supply *psy);
867 
868 extern struct power_supply *__must_check
869 power_supply_register(struct device *parent,
870 				 const struct power_supply_desc *desc,
871 				 const struct power_supply_config *cfg);
872 extern struct power_supply *__must_check
873 power_supply_register_no_ws(struct device *parent,
874 				 const struct power_supply_desc *desc,
875 				 const struct power_supply_config *cfg);
876 extern struct power_supply *__must_check
877 devm_power_supply_register(struct device *parent,
878 				 const struct power_supply_desc *desc,
879 				 const struct power_supply_config *cfg);
880 extern struct power_supply *__must_check
881 devm_power_supply_register_no_ws(struct device *parent,
882 				 const struct power_supply_desc *desc,
883 				 const struct power_supply_config *cfg);
884 extern void power_supply_unregister(struct power_supply *psy);
885 extern int power_supply_powers(struct power_supply *psy, struct device *dev);
886 
887 #define to_power_supply(device) container_of(device, struct power_supply, dev)
888 
889 extern void *power_supply_get_drvdata(struct power_supply *psy);
890 /* For APM emulation, think legacy userspace. */
891 extern struct class *power_supply_class;
892 
893 static inline bool power_supply_is_amp_property(enum power_supply_property psp)
894 {
895 	switch (psp) {
896 	case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
897 	case POWER_SUPPLY_PROP_CHARGE_EMPTY_DESIGN:
898 	case POWER_SUPPLY_PROP_CHARGE_FULL:
899 	case POWER_SUPPLY_PROP_CHARGE_EMPTY:
900 	case POWER_SUPPLY_PROP_CHARGE_NOW:
901 	case POWER_SUPPLY_PROP_CHARGE_AVG:
902 	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
903 	case POWER_SUPPLY_PROP_PRECHARGE_CURRENT:
904 	case POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT:
905 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
906 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
907 	case POWER_SUPPLY_PROP_CURRENT_MAX:
908 	case POWER_SUPPLY_PROP_CURRENT_NOW:
909 	case POWER_SUPPLY_PROP_CURRENT_AVG:
910 	case POWER_SUPPLY_PROP_CURRENT_BOOT:
911 		return true;
912 	default:
913 		break;
914 	}
915 
916 	return false;
917 }
918 
919 static inline bool power_supply_is_watt_property(enum power_supply_property psp)
920 {
921 	switch (psp) {
922 	case POWER_SUPPLY_PROP_ENERGY_FULL_DESIGN:
923 	case POWER_SUPPLY_PROP_ENERGY_EMPTY_DESIGN:
924 	case POWER_SUPPLY_PROP_ENERGY_FULL:
925 	case POWER_SUPPLY_PROP_ENERGY_EMPTY:
926 	case POWER_SUPPLY_PROP_ENERGY_NOW:
927 	case POWER_SUPPLY_PROP_ENERGY_AVG:
928 	case POWER_SUPPLY_PROP_VOLTAGE_MAX:
929 	case POWER_SUPPLY_PROP_VOLTAGE_MIN:
930 	case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
931 	case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
932 	case POWER_SUPPLY_PROP_VOLTAGE_NOW:
933 	case POWER_SUPPLY_PROP_VOLTAGE_AVG:
934 	case POWER_SUPPLY_PROP_VOLTAGE_OCV:
935 	case POWER_SUPPLY_PROP_VOLTAGE_BOOT:
936 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
937 	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
938 	case POWER_SUPPLY_PROP_POWER_NOW:
939 		return true;
940 	default:
941 		break;
942 	}
943 
944 	return false;
945 }
946 
947 #ifdef CONFIG_POWER_SUPPLY_HWMON
948 int power_supply_add_hwmon_sysfs(struct power_supply *psy);
949 void power_supply_remove_hwmon_sysfs(struct power_supply *psy);
950 #else
951 static inline int power_supply_add_hwmon_sysfs(struct power_supply *psy)
952 {
953 	return 0;
954 }
955 
956 static inline
957 void power_supply_remove_hwmon_sysfs(struct power_supply *psy) {}
958 #endif
959 
960 #ifdef CONFIG_SYSFS
961 ssize_t power_supply_charge_behaviour_show(struct device *dev,
962 					   unsigned int available_behaviours,
963 					   enum power_supply_charge_behaviour behaviour,
964 					   char *buf);
965 
966 int power_supply_charge_behaviour_parse(unsigned int available_behaviours, const char *buf);
967 #else
968 static inline
969 ssize_t power_supply_charge_behaviour_show(struct device *dev,
970 					   unsigned int available_behaviours,
971 					   enum power_supply_charge_behaviour behaviour,
972 					   char *buf)
973 {
974 	return -EOPNOTSUPP;
975 }
976 
977 static inline int power_supply_charge_behaviour_parse(unsigned int available_behaviours,
978 						      const char *buf)
979 {
980 	return -EOPNOTSUPP;
981 }
982 #endif
983 
984 #endif /* __LINUX_POWER_SUPPLY_H__ */
985