From: Linus Walleij Date: Fri, 15 Apr 2022 20:36:38 +0000 (+0200) Subject: power: supply: ab8500: Exit maintenance if too low voltage X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=e08f8a118514c94c8cf78aa1dcf5f26f7b6918ba;p=linux.git power: supply: ab8500: Exit maintenance if too low voltage The maintenance charging is supposedly designed such that the maintenance current compensates for the battery discharge curve, and as the charging progress from CC/CV -> maintenance A -> maintenance B states, we end up on a reasonable voltage to restart ordinary CC/CV charging after the safety timer at the maintenance B state exits. However: old batteries discharge quicker, and in an old battery we might not get to the expiration of the maintenance B timer before the battery is completely depleted and the system powers off with an empty battery. This is hardly the desire of anyone leaving their phone in the charger for a few days! Introduce a second clause in both maintenance states such that we exit the state and return to ordinary CC/CV charging if the voltage drops below charge_restart_voltage_uv or 95% if this is not defined for the battery. Signed-off-by: Linus Walleij Reviewed-by: Matti Vaittinen Signed-off-by: Sebastian Reichel --- diff --git a/drivers/power/supply/ab8500_chargalg.c b/drivers/power/supply/ab8500_chargalg.c index 037ae9b4a7d02..f4c017527de4a 100644 --- a/drivers/power/supply/ab8500_chargalg.c +++ b/drivers/power/supply/ab8500_chargalg.c @@ -1514,6 +1514,14 @@ static void ab8500_chargalg_algorithm(struct ab8500_chargalg *di) ab8500_chargalg_stop_maintenance_timer(di); ab8500_chargalg_state_to(di, STATE_MAINTENANCE_B_INIT); } + /* + * This happens if the voltage drops too quickly during + * maintenance charging, especially in older batteries. + */ + if (ab8500_chargalg_time_to_restart(di)) { + ab8500_chargalg_state_to(di, STATE_NORMAL_INIT); + dev_info(di->dev, "restarted charging from maintenance state A - battery getting old?\n"); + } break; case STATE_MAINTENANCE_B_INIT: @@ -1538,6 +1546,14 @@ static void ab8500_chargalg_algorithm(struct ab8500_chargalg *di) ab8500_chargalg_stop_maintenance_timer(di); ab8500_chargalg_state_to(di, STATE_NORMAL_INIT); } + /* + * This happens if the voltage drops too quickly during + * maintenance charging, especially in older batteries. + */ + if (ab8500_chargalg_time_to_restart(di)) { + ab8500_chargalg_state_to(di, STATE_NORMAL_INIT); + dev_info(di->dev, "restarted charging from maintenance state B - battery getting old?\n"); + } break; case STATE_TEMP_LOWHIGH_INIT: