The ThunderSoft TS178 tablet's _BIX implementation reports design_capacity but not full_charge_capacity. Before this commit this would cause us to return -ENODEV for the capacity attribute, which userspace does not like. Specifically upower does this: if (sysfs_file_exists (native_path, "capacity")) { percentage = sysfs_get_double (native_path, "capacity"); Where the sysfs_get_double() helper returns 0 when we return -ENODEV, so the battery always reads 0% if we return -ENODEV. This commit fixes this by using the design-capacity instead of the full-charge-capacity when the full-charge-capacity is not available. Fixes: b41901a2cf06 ("ACPI / battery: Do not export energy_full[_design] on devices without full_charge_capacity") Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- drivers/acpi/battery.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c index 9c0d7c577cb9..6132401f27d7 100644 --- a/drivers/acpi/battery.c +++ b/drivers/acpi/battery.c @@ -217,7 +217,7 @@ static int acpi_battery_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) { - int ret = 0; + int full_capacity = ACPI_BATTERY_VALUE_UNKNOWN, ret = 0; struct acpi_battery *battery = to_acpi_battery(psy); if (acpi_battery_present(battery)) { @@ -286,12 +286,17 @@ static int acpi_battery_get_property(struct power_supply *psy, val->intval = battery->capacity_now * 1000; break; case POWER_SUPPLY_PROP_CAPACITY: + if (ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity)) + full_capacity = battery->full_charge_capacity; + else if (ACPI_BATTERY_CAPACITY_VALID(battery->design_capacity)) + full_capacity = battery->design_capacity; + if (battery->capacity_now == ACPI_BATTERY_VALUE_UNKNOWN || - !ACPI_BATTERY_CAPACITY_VALID(battery->full_charge_capacity)) + full_capacity == ACPI_BATTERY_VALUE_UNKNOWN) ret = -ENODEV; else val->intval = battery->capacity_now * 100/ - battery->full_charge_capacity; + full_capacity; break; case POWER_SUPPLY_PROP_CAPACITY_LEVEL: if (battery->state & ACPI_BATTERY_STATE_CRITICAL) -- 2.23.0