diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/power_supply.h | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h index c135196aa9d1..8ced6550caa7 100644 --- a/include/linux/power_supply.h +++ b/include/linux/power_supply.h @@ -349,6 +349,52 @@ struct power_supply_resistance_temp_table { int resistance; /* internal resistance percent */ }; +/** + * struct power_supply_maintenance_charge_table - setting for maintenace charging + * @charge_current_max_ua: maintenance charging current that is used to keep + * the charge of the battery full as current is consumed after full charging. + * The corresponding charge_voltage_max_uv is used as a safeguard: when we + * reach this voltage the maintenance charging current is turned off. It is + * turned back on if we fall below this voltage. + * @charge_voltage_max_uv: maintenance charging voltage that is usually a bit + * lower than the constant_charge_voltage_max_uv. We can apply this settings + * charge_current_max_ua until we get back up to this voltage. + * @safety_timer_minutes: maintenance charging safety timer, with an expiry + * time in minutes. We will only use maintenance charging in this setting + * for a certain amount of time, then we will first move to the next + * maintenance charge current and voltage pair in respective array and wait + * for the next safety timer timeout, or, if we reached the last maintencance + * charging setting, disable charging until we reach + * charge_restart_voltage_uv and restart ordinary CC/CV charging from there. + * These timers should be chosen to align with the typical discharge curve + * for the battery. + * + * When the main CC/CV charging is complete the battery can optionally be + * maintenance charged at the voltages from this table: a table of settings is + * traversed using a slightly lower current and voltage than what is used for + * CC/CV charging. The maintenance charging will for safety reasons not go on + * indefinately: we lower the current and voltage with successive maintenance + * settings, then disable charging completely after we reach the last one, + * and after that we do not restart charging until we reach + * charge_restart_voltage_uv (see struct power_supply_battery_info) and restart + * ordinary CC/CV charging from there. + * + * As an example, a Samsung EB425161LA Lithium-Ion battery is CC/CV charged + * at 900mA to 4340mV, then maintenance charged at 600mA and 4150mV for + * 60 hours, then maintenance charged at 600mA and 4100mV for 200 hours. + * After this the charge cycle is restarted waiting for + * charge_restart_voltage_uv. + * + * For most mobile electronics this type of maintenance charging is enough for + * the user to disconnect the device and make use of it before both maintenance + * charging cycles are complete. + */ +struct power_supply_maintenance_charge_table { + int charge_current_max_ua; + int charge_voltage_max_uv; + int charge_safety_timer_minutes; +}; + #define POWER_SUPPLY_OCV_TEMP_MAX 20 /** @@ -394,6 +440,10 @@ struct power_supply_resistance_temp_table { * @constant_charge_voltage_max_uv: voltage in microvolts signifying the end of * the CC (constant current) charging phase and the beginning of the CV * (constant voltage) charging phase. + * @maintenance_charge: an array of maintenance charging settings to be used + * after the main CC/CV charging phase is complete. + * @maintenance_charge_size: the number of maintenance charging settings in + * maintenance_charge. * @factory_internal_resistance_uohm: the internal resistance of the battery * at fabrication time, expressed in microohms. This resistance will vary * depending on the lifetime and charge of the battery, so this is just a @@ -543,6 +593,8 @@ struct power_supply_battery_info { int overvoltage_limit_uv; int constant_charge_current_max_ua; int constant_charge_voltage_max_uv; + struct power_supply_maintenance_charge_table *maintenance_charge; + int maintenance_charge_size; int factory_internal_resistance_uohm; int ocv_temp[POWER_SUPPLY_OCV_TEMP_MAX]; int temp_ambient_alert_min; @@ -596,6 +648,8 @@ extern int power_supply_batinfo_ocv2cap(struct power_supply_battery_info *info, extern int power_supply_temp2resist_simple(struct power_supply_resistance_temp_table *table, int table_len, int temp); +extern struct power_supply_maintenance_charge_table * +power_supply_get_maintenance_charging_setting(struct power_supply_battery_info *info, int index); extern void power_supply_changed(struct power_supply *psy); extern int power_supply_am_i_supplied(struct power_supply *psy); int power_supply_get_property_from_supplier(struct power_supply *psy, @@ -603,6 +657,16 @@ int power_supply_get_property_from_supplier(struct power_supply *psy, union power_supply_propval *val); extern int power_supply_set_battery_charged(struct power_supply *psy); +static inline bool +power_supply_supports_maintenance_charging(struct power_supply_battery_info *info) +{ + struct power_supply_maintenance_charge_table *mt; + + mt = power_supply_get_maintenance_charging_setting(info, 0); + + return (mt != NULL); +} + #ifdef CONFIG_POWER_SUPPLY extern int power_supply_is_system_supplied(void); #else |