[PATCH 5.4 174/434] media: aspeed: set hsync and vsync polarities to normal before starting mode detection

Greg Kroah-Hartman
2019-12-29T17:48:25Z

From: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>

[ Upstream commit 5b3f3c41c5c791c1c22cd91655e7ef4b2a1dff7c ]

Sometimes it detects a weird resolution such as 1024x287 when the
actual resolution is 1024x768. To resolve such an issue, this
commit adds clearing for hsync and vsync polarity register bits
at the beginning of the first mode detection. This is recommended
in the datasheet.

Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Reviewed-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/platform/aspeed-video.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/media/platform/aspeed-video.c b/drivers/media/platform/aspeed-video.c
index eb12f3793062..84e0650106f5 100644
--- a/drivers/media/platform/aspeed-video.c
+++ b/drivers/media/platform/aspeed-video.c
@@ -741,6 +741,8 @@ static void aspeed_video_get_resolution(struct aspeed_video *video)
}

set_bit(VIDEO_RES_DETECT, &video->flags);
+ aspeed_video_update(video, VE_CTRL,
+ VE_CTRL_VSYNC_POL | VE_CTRL_HSYNC_POL, 0);
aspeed_video_enable_mode_detect(video);

rc = wait_event_interruptible_timeout(video->wait,
--
2.20.1