power: supply: max17047_battery: The temp alert values are 8-bit 2's complement

The temp alert values are 8-bit 2's complement, so sign-extend them
before reporting them back to the caller.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>

diff --git a/drivers/power/supply/max17042_battery.c b/drivers/power/supply/max17042_battery.c
index 790dfa9d0a2eea4ab1a400a3ccf593df0e1ffdc9..a51b2965cd5c8a26d9adfb1174bc984120a770ae 100644 (file)
--- a/drivers/power/supply/max17042_battery.c
+++ b/drivers/power/supply/max17042_battery.c
@@ -270,14 +270,14 @@ static int max17042_get_property(struct power_supply *psy,
                if (ret < 0)
                        return ret;
                /* LSB is Alert Minimum. In deci-centigrade */
-               val->intval = (data & 0xff) * 10;
+               val->intval = sign_extend32(data & 0xff, 7) * 10;
                break;
        case POWER_SUPPLY_PROP_TEMP_ALERT_MAX:
                ret = regmap_read(map, MAX17042_TALRT_Th, &data);
                if (ret < 0)
                        return ret;
                /* MSB is Alert Maximum. In deci-centigrade */
-               val->intval = (data >> 8) * 10;
+               val->intval = sign_extend32(data >> 8, 7) * 10;
                break;
        case POWER_SUPPLY_PROP_TEMP_MIN:
                val->intval = chip->pdata->temp_min;