Hi Prabhakar,
Thank you for the patch.
On Sun, Mar 15, 2020 at 10:27:24AM +0000, Lad Prabhakar wrote:
> The rcar-csi2 driver uses the v4l2-async framework to do endpoint matching
> instead of node matching. This is needed as it needs to work with the
> adv748x driver which register it self in v4l2-async using endpoints
> instead of nodes. The reason for this is that from a single DT node it
> creates multiple subdevices, one for each endpoint.
>
> But when using subdevs which register itself in v4l2-async using nodes,
> the rcar-csi2 driver failed to find the matching endpoint because the
> match.fwnode was pointing to remote endpoint instead of remote parent
> port.
>
> This commit adds support in rcar-csi2 driver to handle both the cases
> where subdev registers in v4l2-async using endpoints/nodes, by using
> match_type as V4L2_ASYNC_MATCH_CUSTOM and implementing the match()
> callback to compare the fwnode of either remote/parent.
This is not the way to go. The v4l2-async framework needs to be fixed
instead, so that fwnode match will do the right thing automatically
regardless of whether the node is a device node or and endpoint node.
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> ---
> drivers/media/platform/rcar-vin/rcar-csi2.c | 46 +++++++++++++++++++--
> 1 file changed, 43 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
> index faa9fb23a2e9..1bbf05e9f025 100644
> --- a/drivers/media/platform/rcar-vin/rcar-csi2.c
> +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> @@ -808,6 +808,46 @@ static int rcsi2_parse_v4l2(struct rcar_csi2 *priv,
> return 0;
> }
>
> +static bool rcsi2_asd_match(struct v4l2_subdev *sd,
> + struct v4l2_async_subdev *asd)
> +{
> + struct rcar_csi2 *priv = (struct rcar_csi2 *)asd->match.custom.priv;
> + struct fwnode_handle *remote_endpoint;
> + struct fwnode_handle *subdev_endpoint;
> + struct device_node *np;
> + bool matched = false;
> +
> + np = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> + if (!np) {
> + dev_err(priv->dev, "Not connected to subdevice\n");
> + return matched;
> + }
> +
> + remote_endpoint =
> + fwnode_graph_get_remote_endpoint(of_fwnode_handle(np));
> + if (!remote_endpoint) {
> + dev_err(priv->dev, "Failed to get remote endpoint\n");
> + of_node_put(np);
> + return matched;
> + }
> + of_node_put(np);
> +
> + if (sd->fwnode != dev_fwnode(sd->dev)) {
> + if (remote_endpoint == sd->fwnode)
> + matched = true;
> + } else {
> + subdev_endpoint =
> + fwnode_graph_get_next_endpoint(dev_fwnode(sd->dev), NULL);
> + if (remote_endpoint == subdev_endpoint)
> + matched = true;
> + fwnode_handle_put(subdev_endpoint);
> + }
> +
> + fwnode_handle_put(remote_endpoint);
> +
> + return matched;
> +}
> +
> static int rcsi2_parse_dt(struct rcar_csi2 *priv)
> {
> struct device_node *ep;
> @@ -833,9 +873,9 @@ static int rcsi2_parse_dt(struct rcar_csi2 *priv)
> return ret;
> }
>
> - priv->asd.match.fwnode =
> - fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep));
> - priv->asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
> + priv->asd.match.custom.match = &rcsi2_asd_match;
> + priv->asd.match.custom.priv = priv;
> + priv->asd.match_type = V4L2_ASYNC_MATCH_CUSTOM;
>
> of_node_put(ep);
>
--
Regards,
Laurent Pinchart
