[media] uvcvideo: Fix reading the current exposure value of UVC

V4L2_CID_EXPOSURE_ABSOLUTE property does not return an updated value when
autoexposure (V4L2_CID_EXPOSURE_AUTO) is turned on. This patch fixes this
issue by adding the UVC_CTRL_FLAG_AUTO_UPDATE flag.

Tested on a C920 camera.

Signed-off-by: Anton V. Shokurov <shokurov.anton.v@yandex.ru>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
index 3e59b28..c2ee6e3 100644 (file)
--- a/drivers/media/usb/uvc/uvc_ctrl.c
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -227,7 +227,8 @@ static struct uvc_control_info uvc_ctrls[] = {
                .size           = 4,
                .flags          = UVC_CTRL_FLAG_SET_CUR
                                | UVC_CTRL_FLAG_GET_RANGE
-                               | UVC_CTRL_FLAG_RESTORE,
+                               | UVC_CTRL_FLAG_RESTORE
+                               | UVC_CTRL_FLAG_AUTO_UPDATE,
        },
        {
                .entity         = UVC_GUID_UVC_CAMERA,