[PATCH 4.19 179/243] media: stkwebcam: Bugfix for wrong return values

[Greg Kroah-Hartman]

From: Andreas Pape <ap@xxxxxxxxxx>

[ Upstream commit 3c28b91380dd1183347d32d87d820818031ebecf ]

usb_control_msg returns in case of a successfully sent message the number
of sent bytes as a positive number. Don't use this value as a return value
for stk_camera_read_reg, as a non-zero return value is used as an error
condition in some cases when stk_camera_read_reg is called.

Signed-off-by: Andreas Pape <ap@xxxxxxxxxx>
Reviewed-by: Kieran Bingham <kieran.bingham@xxxxxxxxxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/media/usb/stkwebcam/stk-webcam.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/media/usb/stkwebcam/stk-webcam.c b/drivers/media/usb/stkwebcam/stk-webcam.c
index 6e3f234e790b8..e33fa78ef98dd 100644
--- a/drivers/media/usb/stkwebcam/stk-webcam.c
+++ b/drivers/media/usb/stkwebcam/stk-webcam.c
@@ -164,7 +164,11 @@ int stk_camera_read_reg(struct stk_camera *dev, u16 index, u8 *value)
 		*value = *buf;
 
 	kfree(buf);
-	return ret;
+
+	if (ret < 0)
+		return ret;
+	else
+		return 0;
 }
 
 static int stk_start_stream(struct stk_camera *dev)
-- 
2.20.1