power: supply: max17042_battery: Prevent int underflow in set_soc_threshold

commit e660dbb68c6b3f7b9eb8b9775846a44f9798b719 upstream.

max17042_set_soc_threshold gets called with offset set to 1, which means
that minimum threshold value would underflow once SOC got down to 0,
causing invalid alerts from the gauge.

Fixes: e5f3872d20 ("max17042: Add support for signalling change in SOC")
Cc: <stable@vger.kernel.org>
Signed-off-by: Sebastian Krzyszkowiak <sebastian.krzyszkowiak@puri.sm>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Sebastian Krzyszkowiak
2021-09-14 14:18:06 +02:00
committed by Greg Kroah-Hartman
parent 5720436bc7
commit f2feac81ed

View File

@@ -851,7 +851,8 @@ static void max17042_set_soc_threshold(struct max17042_chip *chip, u16 off)
regmap_read(map, MAX17042_RepSOC, &soc); regmap_read(map, MAX17042_RepSOC, &soc);
soc >>= 8; soc >>= 8;
soc_tr = (soc + off) << 8; soc_tr = (soc + off) << 8;
soc_tr |= (soc - off); if (off < soc)
soc_tr |= soc - off;
regmap_write(map, MAX17042_SALRT_Th, soc_tr); regmap_write(map, MAX17042_SALRT_Th, soc_tr);
} }