[PATCH AUTOSEL 4.9 22/64] ASoC: sgtl5000: avoid division by zero if lo_vag is zero

Sasha Levin
2019-11-08T11:46:33Z

From: Colin Ian King <colin.king@canonical.com>

[ Upstream commit 9ab708aef61f5620113269a9d1bdb1543d1207d0 ]

In the case where lo_vag <= SGTL5000_LINE_OUT_GND_BASE, lo_vag
is set to zero and later vol_quot is computed by dividing by
lo_vag causing a division by zero error. Fix this by avoiding
a zero division and set vol_quot to zero in this specific case
so that the lowest setting for i is correctly set.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
sound/soc/codecs/sgtl5000.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sound/soc/codecs/sgtl5000.c b/sound/soc/codecs/sgtl5000.c
index 7406ea5c9a4f7..39810b713d5f2 100644
--- a/sound/soc/codecs/sgtl5000.c
+++ b/sound/soc/codecs/sgtl5000.c
@@ -1217,7 +1217,7 @@ static int sgtl5000_set_power_regs(struct snd_soc_codec *codec)
* Searching for a suitable index solving this formula:
* idx = 40 * log10(vag_val / lo_cagcntrl) + 15
*/
- vol_quot = (vag * 100) / lo_vag;
+ vol_quot = lo_vag ? (vag * 100) / lo_vag : 0;
lo_vol = 0;
for (i = 0; i < ARRAY_SIZE(vol_quot_table); i++) {
if (vol_quot >= vol_quot_table[i])
--
2.20.1