Hi Laurent,
Thank you for the quick review.
On Sun, Mar 15, 2020 at 10:30 AM Laurent Pinchart
<laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
>
> 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.
>
OK, so moving forward should the v4l2-async do strictly endpoint
matching only or
both nodes/endpoints. fwnode in all the bridge drivers be replaced to
remote endpoints ?
Looking at the adv7604 its registered as node to v4l2-async which can
have upto 3 endpoints,
adv748x is the single driver which registers itself as endpoint to
v4l2-async, and rest of the
other subdevices have single endpoint and are registered as node to
v4l2-async. How would you
suggest to handle these cases.
Cheers,
--Prabhakar Lad
> > 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
