[PATCH 6.19 583/844] media: ccs: Avoid possible division by zero

[Sasha Levin]

From: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>

[ Upstream commit 679f0b7b6a409750a25754c8833e268e5fdde742 ]

Calculating maximum M for scaler configuration involves dividing by
MIN_X_OUTPUT_SIZE limit register's value. Albeit the value is presumably
non-zero, the driver was missing the check it in fact was. Fix this.

Reported-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Closes: https://lore.kernel.org/all/ahukd6b3wonye3zgtptvwzvrxldcruazs2exfvll6etjhmcxyj@vq3eh6pd375b/
Fixes: ccfc97bdb5ae ("[media] smiapp: Add driver")
Cc: stable@xxxxxxxxxxxxxxx # for 5.15 and later
Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Tested-by: Nathan Chancellor <nathan@xxxxxxxxxx> # build
Signed-off-by: Hans Verkuil <hverkuil+cisco@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/media/i2c/ccs/ccs-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/i2c/ccs/ccs-core.c b/drivers/media/i2c/ccs/ccs-core.c
index 43f7d515bab67..3cacc7d904935 100644
--- a/drivers/media/i2c/ccs/ccs-core.c
+++ b/drivers/media/i2c/ccs/ccs-core.c
@@ -2346,7 +2346,7 @@ static void ccs_set_compose_scaler(struct v4l2_subdev *subdev,
 		* CCS_LIM(sensor, SCALER_N_MIN) / sel->r.height;
 	max_m = crops[CCS_PAD_SINK]->width
 		* CCS_LIM(sensor, SCALER_N_MIN)
-		/ CCS_LIM(sensor, MIN_X_OUTPUT_SIZE);
+		/ (CCS_LIM(sensor, MIN_X_OUTPUT_SIZE) ?: 1);
 
 	a = clamp(a, CCS_LIM(sensor, SCALER_M_MIN),
 		  CCS_LIM(sensor, SCALER_M_MAX));
-- 
2.51.0