include/linux/power_supply.h

1 /* SPDX-License-Identifier: GPL-2.0-only */
29  * For systems where the charger determines the maximum battery capacity
226 /* Run-time specific power supply configuration */
344 	int ocv;	/* microVolts */  member
345 	int capacity;	/* percent */  member
359  * struct power_supply_maintenance_charge_table - setting for maintenace charging
392  *  +-------------------------------------------------------------------> t
394  * Practically this means that the Li-ions are wandering back and forth in the
405  *  +-------------------------------------------------------------------> t
407  * Maintenance charging uses the voltages from this table: a table of settings
416  * As an example, a Samsung EB425161LA Lithium-Ion battery is CC/CV charged
431  * the expected stand-by current. Also overvoltage protection will be applied
443  * struct power_supply_battery_info - information about batteries
513  * @ocv_temp: array indicating the open circuit voltage (OCV) capacity
515  *   indicating which capacity table to use for a certain temperature, since
516  *   the capacity for reasons of chemistry will be different at different
517  *   temperatures. Determining capacity is a multivariate problem and the
537  *   determine the capacity in percent in relation to the voltage in microvolts
540  *   each entry in the array of capacity arrays in ocv_table.
541  * @resist_table: this is a table that correlates a battery temperature to the
545  *   circuit voltage (OCV) that is then used with the ocv_table to calculate
546  *   the capacity of the battery. The resist_table must be ordered descending
550  * @vbat2ri_discharging: this is a table that correlates Battery voltage (VBAT)
553  *   determine the open circuit voltage so that we can determine the capacity
555  *   is discharging. The table must be ordered descending by voltage: highest
558  *   table.
561  *   internal resistance characteristics so a separate table is needed.*
562  *   The table must be ordered descending by voltage: highest voltage first.
564  *   table.
570  *   for example 10 for +/- 10%, if the bti_resistance is set to 7000 and the
579  * The default field value is -EINVAL or NULL for pointers.
588  * |                                               --- overvoltage_limit_uv
601  * +------------------------------------------------------------------> time
618  * +-----------------------------------------------------------------> time
629  * 2. Next a small initial pre-charge current (precharge_current_ua)
666  * DETERMINING BATTERY CAPACITY:
669  * capacity in the battery, usually as a percentage of charge. In practice
670  * many chargers uses a so-called fuel gauge or coloumb counter that measure
671  * how much charge goes into the battery and how much goes out (+/- leak
672  * consumption). This does not help if we do not know how much capacity the
674  * and charged in a separate charger. Therefore many capacity algorithms use
675  * the open circuit voltage with a look-up table to determine the rough
676  * capacity of the battery. The open circuit voltage can be conceptualized
680  *      +-------> IBAT >----------------+
684  *      o <----------        |          |
686  *    .---.         |        |          |
687  *    | V |         | OCV    |          |
688  *    '---'         |        |          |
690  *  GND +-------------------------------+
694  * VBAT = OCV and this assumption is sometimes made even under load, assuming
697  * temperature and how much capacity is left in the battery due to the
705  *   OCV = VBAT - (IBAT * Ri)
710  * some batteries. This gives the compensated open circuit voltage (OCV) for
714  * VBAT to Ri takes both remaining capacity and temperature into consideration.
716  * Alternatively a manufacturer can specify how the capacity of the battery
721  * the purpose of the table resist_table: this will take a temperature and
805 extern int power_supply_ocv2cap_simple(struct power_supply_battery_ocv_table *table,
806 				       int table_len, int ocv);
811 					int ocv, int temp);
813 power_supply_temp2resist_simple(struct power_supply_resistance_temp_table *table,
841 	return ((info->vbat2ri_discharging != NULL) &&  in power_supply_supports_vbat2ri()
842 		info->vbat2ri_discharging_size > 0);  in power_supply_supports_vbat2ri()
848 	return ((info->resist_table != NULL) &&  in power_supply_supports_temp2ri()
849 		info->resist_table_size > 0);  in power_supply_supports_temp2ri()
855 static inline int power_supply_is_system_supplied(void) { return -ENOSYS; }  in power_supply_is_system_supplied()
981 	return -EOPNOTSUPP;  in power_supply_charge_behaviour_show()
987 	return -EOPNOTSUPP;  in power_supply_charge_behaviour_parse()