From 19fffc8450d4378580a8f019b195c4617083176f Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Thu, 12 Apr 2018 12:01:59 +0200 Subject: [PATCH] ACPI / battery: Add handling for devices which wrongly report discharging state On quite a few devices the battery code in the ACPI tables is buggy and first checks the charging status bits of the charger-IC, and if those report not charging it will report discharging, without looking at the presence of AC power or at the battery dis(charge) current from the fuel-gauge. This causes the wrong status to be reported for the battery in the following quite common scenario: 1) Plug in charger while battery is say half full, battery starts charging, charging state bits indicate: pre-charge or fast-charge, ACPI reported battery status is ok 2) When fully charged charging state bits indicate: end-of-charge, ACPI reported battery status is ok 3) unplug the charger, wait 1 minute, replug. Now the battery voltage is still above the start-charging threshold, so the charger will not start charging to avoid wrecking the battery by repeatedly recharging the last 1% capacity. The charger IC charging state bits now are all 0 (not-charging) and the broken ACPI code wrongly translate this to "discharging" and ends up setting the ACPI_BATTERY_STATE_DISCHARGING bit in its state field. Reporting this "not charging" state as discharging is confusing for users, making the user think his adapter/power-brick is broken or not properly plugged in. This commit adds a helper for handling the ACPI_BATTERY_STATE_DISCHARGING state. This helper checks if we're an AC and the current going out of the battery is 0 and in that case reports a status of "not charging" to userspace rather then "discharging". This replaces commit c68f0676ef7d ("ACPI / battery: Add quirk for Asus GL502VSK and UX305LA"), a previous fix for this which was reverted. Signed-off-by: Hans de Goede Reviewed-by: Daniel Drake Reviewed-by: Sebastian Reichel Signed-off-by: Rafael J. Wysocki --- drivers/acpi/battery.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c index 338432cbef09..bd36cb5c3fe1 100644 --- a/drivers/acpi/battery.c +++ b/drivers/acpi/battery.c @@ -215,6 +215,19 @@ static bool acpi_battery_is_degraded(struct acpi_battery *battery) battery->full_charge_capacity < battery->design_capacity; } +static int acpi_battery_handle_discharging(struct acpi_battery *battery) +{ + /* + * Some devices wrongly report discharging if the battery's charge level + * was above the device's start charging threshold atm the AC adapter + * was plugged in and the device thus did not start a new charge cycle. + */ + if (power_supply_is_system_supplied() && battery->rate_now == 0) + return POWER_SUPPLY_STATUS_NOT_CHARGING; + + return POWER_SUPPLY_STATUS_DISCHARGING; +} + static int acpi_battery_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) @@ -230,7 +243,7 @@ static int acpi_battery_get_property(struct power_supply *psy, switch (psp) { case POWER_SUPPLY_PROP_STATUS: if (battery->state & ACPI_BATTERY_STATE_DISCHARGING) - val->intval = POWER_SUPPLY_STATUS_DISCHARGING; + val->intval = acpi_battery_handle_discharging(battery); else if (battery->state & ACPI_BATTERY_STATE_CHARGING) val->intval = POWER_SUPPLY_STATUS_CHARGING; else if (acpi_battery_is_charged(battery))