Hi Laurent,
Thanks for the patch.
On Sun, Mar 15, 2020 at 02:55:11PM +0200, Laurent Pinchart wrote:
> fwnode matching was designed to match on nodes corresponding to a
> device. Some drivers, however, needed to match on endpoints, and have
> passed endpoint fwnodes to v4l2-async. This works when both the subdev
> and the notifier use the same fwnode types (endpoint or device), but
> makes drivers that use different types incompatible.
>
> Fix this by extending the fwnode match to handle fwnodes of different
> types. When the types (deduced from the node name) are different,
> retrieve the device fwnode for the side that provides an endpoint
> fwnode, and compare it with the device fwnode provided by the other
> side. This allows interoperability between all drivers, regardless of
> which type of fwnode they use for matching.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
> ---
> This has been compile-tested only. Prabhakar, could you check if it
> fixes your issue ?
>
> drivers/media/v4l2-core/v4l2-async.c | 42 +++++++++++++++++++++++++++-
> 1 file changed, 41 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c
> index 8bde33c21ce4..995e5464cba7 100644
> --- a/drivers/media/v4l2-core/v4l2-async.c
> +++ b/drivers/media/v4l2-core/v4l2-async.c
> @@ -71,7 +71,47 @@ static bool match_devname(struct v4l2_subdev *sd,
>
> static bool match_fwnode(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd)
> {
> - return sd->fwnode == asd->match.fwnode;
> + struct fwnode_handle *other_fwnode;
> + struct fwnode_handle *dev_fwnode;
> + bool asd_fwnode_is_ep;
> + bool sd_fwnode_is_ep;
> + const char *name;
> +
> + /*
> + * Both the subdev and the async subdev can provide either an endpoint
> + * fwnode or a device fwnode. Start with the simple case of direct
> + * fwnode matching.
> + */
> + if (sd->fwnode == asd->match.fwnode)
> + return true;
> +
> + /*
> + * Otherwise, check if the sd fwnode and the asd fwnode refer to an
> + * endpoint or a device. If they're of the same type, there's no match.
> + */
> + name = fwnode_get_name(sd->fwnode);
> + sd_fwnode_is_ep = name && strstarts(name, "endpoint");
> + name = fwnode_get_name(asd->match.fwnode);
> + asd_fwnode_is_ep = name && strstarts(name, "endpoint");
Apart from the fact that you're parsing graph node names here, this looks
good.
How about checking instead that calling
fwnode_graph_get_remote_endpoint(fwnode_graph_get_remote_endpoint()) yields
the same node? That would ensure you're dealing with endpoint nodes without
explicitly parsing the graph in any way.
Just remember to drop the references.
> +
> + if (sd_fwnode_is_ep == asd_fwnode_is_ep)
> + return false;
> +
> + /*
> + * The sd and asd fwnodes are of different types. Get the device fwnode
> + * parent of the endpoint fwnode, and compare it with the other fwnode.
> + */
> + if (sd_fwnode_is_ep) {
> + dev_fwnode = fwnode_graph_get_port_parent(sd->fwnode);
> + other_fwnode = asd->match.fwnode;
> + } else {
> + dev_fwnode = fwnode_graph_get_port_parent(asd->match.fwnode);
> + other_fwnode = sd->fwnode;
> + }
> +
> + fwnode_handle_put(dev_fwnode);
> +
> + return dev_fwnode == other_fwnode;
> }
>
> static bool match_custom(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd)
--
Kind regards,
Sakari Ailus
