| From 9097c73c41e543e2b5459fedd6a6fc0412b5de4c Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Mon, 17 May 2021 16:29:23 +0200 |
| Subject: media: imx-csi: Skip first few frames from a BT.656 source |
| |
| From: Steve Longerbeam <slongerbeam@gmail.com> |
| |
| [ Upstream commit e198be37e52551bb863d07d2edc535d0932a3c4f ] |
| |
| Some BT.656 sensors (e.g. ADV718x) transmit frames with unstable BT.656 |
| sync codes after initial power on. This confuses the imx CSI,resulting |
| in vertical and/or horizontal sync issues. Skip the first 20 frames |
| to avoid the unstable sync codes. |
| |
| [fabio: fixed checkpatch warning and increased the frame skipping to 20] |
| |
| Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com> |
| Signed-off-by: Fabio Estevam <festevam@gmail.com> |
| Reviewed-by: Tim Harvey <tharvey@gateworks.com> |
| Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> |
| Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| drivers/staging/media/imx/imx-media-csi.c | 14 +++++++++++++- |
| 1 file changed, 13 insertions(+), 1 deletion(-) |
| |
| diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c |
| index 21ebf7769696..899d29f4c91a 100644 |
| --- a/drivers/staging/media/imx/imx-media-csi.c |
| +++ b/drivers/staging/media/imx/imx-media-csi.c |
| @@ -753,9 +753,10 @@ static int csi_setup(struct csi_priv *priv) |
| |
| static int csi_start(struct csi_priv *priv) |
| { |
| - struct v4l2_fract *output_fi; |
| + struct v4l2_fract *input_fi, *output_fi; |
| int ret; |
| |
| + input_fi = &priv->frame_interval[CSI_SINK_PAD]; |
| output_fi = &priv->frame_interval[priv->active_output_pad]; |
| |
| /* start upstream */ |
| @@ -764,6 +765,17 @@ static int csi_start(struct csi_priv *priv) |
| if (ret) |
| return ret; |
| |
| + /* Skip first few frames from a BT.656 source */ |
| + if (priv->upstream_ep.bus_type == V4L2_MBUS_BT656) { |
| + u32 delay_usec, bad_frames = 20; |
| + |
| + delay_usec = DIV_ROUND_UP_ULL((u64)USEC_PER_SEC * |
| + input_fi->numerator * bad_frames, |
| + input_fi->denominator); |
| + |
| + usleep_range(delay_usec, delay_usec + 1000); |
| + } |
| + |
| if (priv->dest == IPU_CSI_DEST_IDMAC) { |
| ret = csi_idmac_start(priv); |
| if (ret) |
| -- |
| 2.30.2 |
| |