The code in imx7_csi_pad_link_validate() that checks the type of the
source incorrectly handles devices that have no parallel input. In that
case, the source entity of the CSI is the CSI-2 receiver, not the video
mux, and the driver will proceed to check the type of the source of the
CSI-2 receiver.
Make the code more explicit to fix this, by handling the three cases
(parallel input only, CSI-2 receiver only, and video mux) separately.
Note that the driver will not correctly handle the case where only a
parallel input is present, and the external entity connected to the
parallel input reports a MEDIA_ENT_F_VID_IF_BRIDGE or
MEDIA_ENT_F_VID_MUX function. This was broken already, and should be
fixed separately.
Fixes: f168e796bf40 ("media: imx7: csi: Fix pad link validation")
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
drivers/staging/media/imx/imx7-media-csi.c | 52 +++++++++++++---------
1 file changed, 30 insertions(+), 22 deletions(-)
diff --git a/drivers/staging/media/imx/imx7-media-csi.c b/drivers/staging/media/imx/imx7-media-csi.c
index de7b93317a47..2a4b69cc0178 100644
--- a/drivers/staging/media/imx/imx7-media-csi.c
+++ b/drivers/staging/media/imx/imx7-media-csi.c
@@ -1000,39 +1000,47 @@ static int imx7_csi_pad_link_validate(struct v4l2_subdev *sd,
struct imx7_csi *csi = v4l2_get_subdevdata(sd);
struct imx_media_video_dev *vdev = csi->vdev;
const struct v4l2_pix_format *out_pix = &vdev->fmt;
- struct media_entity *src;
struct media_pad *pad;
+ bool is_csi2;
int ret;
- /*
- * Validate the source link, and record whether the CSI mux selects the
- * parallel input or the CSI-2 receiver.
- */
- ret = v4l2_subdev_link_validate_default(sd, link, source_fmt, sink_fmt);
- if (ret)
- return ret;
-
if (!csi->src_sd)
return -EPIPE;
- src = &csi->src_sd->entity;
-
/*
- * if the source is neither a CSI MUX or CSI-2 get the one directly
- * upstream from this CSI
+ * Validate the source link, and record whether the source uses the
+ * parallel input or the CSI-2 receiver.
*/
- if (src->function != MEDIA_ENT_F_VID_IF_BRIDGE &&
- src->function != MEDIA_ENT_F_VID_MUX)
- src = &csi->sd.entity;
+ ret = v4l2_subdev_link_validate_default(sd, link, source_fmt, sink_fmt);
+ if (ret)
+ return ret;
- pad = imx_media_pipeline_pad(src, 0, 0, true);
- if (!pad)
- return -ENODEV;
+ switch (csi->src_sd->entity.function) {
+ case MEDIA_ENT_F_VID_IF_BRIDGE:
+ /* The input is the CSI-2 receiver. */
+ is_csi2 = true;
+ break;
+
+ case MEDIA_ENT_F_VID_MUX:
+ /* The input is the mux, check its input. */
+ pad = imx_media_pipeline_pad(&csi->src_sd->entity, 0, 0, true);
+ if (!pad)
+ return -ENODEV;
+
+ is_csi2 = pad->entity->function == MEDIA_ENT_F_VID_IF_BRIDGE;
+ break;
+
+ default:
+ /*
+ * The input is an external entity, it must use the parallel
+ * bus.
+ */
+ is_csi2 = false;
+ break;
+ }
mutex_lock(&csi->lock);
-
- csi->is_csi2 = (pad->entity->function == MEDIA_ENT_F_VID_IF_BRIDGE);
-
+ csi->is_csi2 = is_csi2;
mutex_unlock(&csi->lock);
/* Validate the sink link, ensure the pixel format is supported. */
--
Regards,
Laurent Pinchart
