[PATCH v4 07/17] media: video-mux: Implement get_fwnode_pad op

[Steve Longerbeam <slongerbeam@gmail.com>]

Implement get_fwnode_pad operation. If the endpoint is owned by the video
mux, return the endpoint's port number. The video mux maps fwnode port
numbers and pad indexes 1:1.

Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
---
 drivers/media/platform/video-mux.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/drivers/media/platform/video-mux.c b/drivers/media/platform/video-mux.c
index 7b6c96a29aa5..f446ada82176 100644
--- a/drivers/media/platform/video-mux.c
+++ b/drivers/media/platform/video-mux.c
@@ -94,9 +94,38 @@ static int video_mux_link_setup(struct media_entity *entity,
 	return ret;
 }
 
+static int video_mux_get_fwnode_pad(struct media_entity *entity,
+				    struct fwnode_endpoint *endpoint)
+{
+	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
+	struct video_mux *vmux = v4l2_subdev_to_video_mux(sd);
+	struct fwnode_handle *vmux_fwnode = dev_fwnode(vmux->subdev.dev);
+	struct fwnode_handle *vmux_ep;
+
+	/*
+	 * If the endpoint is one of ours, return the endpoint's port
+	 * number. This device maps port numbers and pad indexes 1:1.
+	 */
+	fwnode_graph_for_each_endpoint(vmux_fwnode, vmux_ep) {
+		if (endpoint->local_fwnode == vmux_ep) {
+			struct fwnode_endpoint fwep;
+			int ret;
+
+			ret = fwnode_graph_parse_endpoint(vmux_ep, &fwep);
+
+			fwnode_handle_put(vmux_ep);
+
+			return ret ? ret : fwep.port;
+		}
+	}
+
+	return -ENXIO;
+}
+
 static const struct media_entity_operations video_mux_ops = {
 	.link_setup = video_mux_link_setup,
 	.link_validate = v4l2_subdev_link_validate,
+	.get_fwnode_pad = video_mux_get_fwnode_pad,
 };
 
 static int video_mux_s_stream(struct v4l2_subdev *sd, int enable)
-- 
2.17.1