media: imx: csi: Implement get_fwnode_pad op

The CSI does not have a 1:1 relationship between fwnode port numbers and
pad indexes. In fact the CSI fwnode device is itself a port which is the
sink, containing only a single fwnode endpoint. Implement media_entity
operation get_fwnode_pad to first verify the given endpoint is the CSI's
sink endpoint, and if so return the CSI sink pad index.

Signed-off-by: Steve Longerbeam <slongerbeam@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/staging/media/imx/imx-media-csi.c b/drivers/staging/media/imx/imx-media-csi.c
index 905b1ee27db6702124fa9dd272798137b404ad6c..08f698af47979347f88bc73a8f8df44478808e5e 100644 (file)
--- a/drivers/staging/media/imx/imx-media-csi.c
+++ b/drivers/staging/media/imx/imx-media-csi.c
@@ -1832,9 +1832,32 @@ static void csi_unregistered(struct v4l2_subdev *sd)
                ipu_csi_put(priv->csi);
 }
 
+/*
+ * The CSI has only one fwnode endpoint, at the sink pad. Verify the
+ * endpoint belongs to us, and return CSI_SINK_PAD.
+ */
+static int csi_get_fwnode_pad(struct media_entity *entity,
+                             struct fwnode_endpoint *endpoint)
+{
+       struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
+       struct csi_priv *priv = v4l2_get_subdevdata(sd);
+       struct fwnode_handle *csi_port = dev_fwnode(priv->dev);
+       struct fwnode_handle *csi_ep;
+       int ret;
+
+       csi_ep = fwnode_get_next_child_node(csi_port, NULL);
+
+       ret = endpoint->local_fwnode == csi_ep ? CSI_SINK_PAD : -ENXIO;
+
+       fwnode_handle_put(csi_ep);
+
+       return ret;
+}
+
 static const struct media_entity_operations csi_entity_ops = {
        .link_setup = csi_link_setup,
        .link_validate = v4l2_subdev_link_validate,
+       .get_fwnode_pad = csi_get_fwnode_pad,
 };
 
 static const struct v4l2_subdev_core_ops csi_core_ops = {