media: aspeed: fix mode-detect always time out at 2nd run

aspeed_video_get_resolution() will try to do res-detect again if the
timing got in last try is invalid. But it will always time out because
VE_SEQ_CTRL_TRIG_MODE_DET is only cleared after 1st mode-detect.

To fix the problem, just clear VE_SEQ_CTRL_TRIG_MODE_DET before setting
it in aspeed_video_enable_mode_detect().

Fixes: d2b4387f ("media: platform: Add Aspeed Video Engine driver")
Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com>
Acked-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/aspeed-video.c

@@ -539,6 +539,10 @@ static void aspeed_video_enable_mode_detect(struct aspeed_video *video)
 	aspeed_video_update(video, VE_INTERRUPT_CTRL, 0,
 			    VE_INTERRUPT_MODE_DETECT);
 
+	/* Disable mode detect in order to re-trigger */
+	aspeed_video_update(video, VE_SEQ_CTRL,
+			    VE_SEQ_CTRL_TRIG_MODE_DET, 0);
+
 	/* Trigger mode detect */
 	aspeed_video_update(video, VE_SEQ_CTRL, 0, VE_SEQ_CTRL_TRIG_MODE_DET);
 }
@@ -824,10 +828,6 @@ static void aspeed_video_get_resolution(struct aspeed_video *video)
 			return;
 		}
 
-		/* Disable mode detect in order to re-trigger */
-		aspeed_video_update(video, VE_SEQ_CTRL,
-				    VE_SEQ_CTRL_TRIG_MODE_DET, 0);
-
 		aspeed_video_check_and_set_polarity(video);
 
 		aspeed_video_enable_mode_detect(video);