Re: ACPI: Always return valid 'status' from acpi_battery_get_property()

Alexey Starikovskiy
2007-11-08T08:29:33Z

Thanks,
Alex.

Roland Dreier wrote:
> If a battery is at a critical charge level and not being charged or
> discharged, then the ACPI _BST method will return a state of 4, and
> the current acpi_battery_get_property() code will not set any property
> value for POWER_SUPPLY_PROP_STATUS. This will cause an oops in
> power_supply_show_property() when it reads off the end of the
> status_text array. This actually was causing a 100% reproducible
> crash on boot on my laptop with two batteries, when one battery was
> completely drained and the laptop was not plugged in.
>
> Fix this by making sure acpi_battery_get_property() returns
> POWER_SUPPLY_STATUS_UNKNOWN for any battery state it doesn't already
> handle explicitly. There doesn't seem to be any status enum value
> defined that makes more sense than 'unknown' for a battery at a
> critical charge level.
>
> Signed-off-by: Roland Dreier <roland@digitalvampire.org>
Acked-by: Alexey Starikovskiy <astarikovskiy@suse.de>
> ---
> diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
> index c2ce0ad..cbb27b4 100644
> --- a/drivers/acpi/battery.c
> +++ b/drivers/acpi/battery.c
> @@ -152,6 +152,8 @@ static int acpi_battery_get_property(struct power_supply *psy,
> val->intval = POWER_SUPPLY_STATUS_CHARGING;
> else if (battery->state == 0)
> val->intval = POWER_SUPPLY_STATUS_FULL;
> + else
> + val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
> break;
> case POWER_SUPPLY_PROP_PRESENT:
> val->intval = acpi_battery_present(battery);