From 165ca6e8ac5bb208f8b72c4e39e0b0f5ff4d6009 Mon Sep 17 00:00:00 2001 From: Sebastian Krzyszkowiak Date: Tue, 14 Sep 2021 14:18:06 +0200 Subject: [PATCH] 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: e5f3872d2044 ("max17042: Add support for signalling change in SOC") Cc: Signed-off-by: Sebastian Krzyszkowiak Reviewed-by: Krzysztof Kozlowski Signed-off-by: Sebastian Reichel Signed-off-by: Greg Kroah-Hartman --- drivers/power/supply/max17042_battery.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/power/supply/max17042_battery.c b/drivers/power/supply/max17042_battery.c index 8dffae76b6a3..416c1d4bb628 100644 --- a/drivers/power/supply/max17042_battery.c +++ b/drivers/power/supply/max17042_battery.c @@ -857,7 +857,8 @@ static void max17042_set_soc_threshold(struct max17042_chip *chip, u16 off) regmap_read(map, MAX17042_RepSOC, &soc); soc >>= 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); } -- 2.34.1