drm: convert drivers to use of_graph_get_remote_node

Convert drivers to use the new of_graph_get_remote_node() helper
instead of parsing the endpoint node and then getting the remote device
node. Now drivers can just specify the device node and which
port/endpoint and get back the connected remote device node. The details
of the graph binding are nicely abstracted into the core OF graph code.

This changes some error messages to debug messages (in the graph core).
Graph connections are often "no connects" depending on the particular
board, so we want to avoid spurious messages. Plus the kernel is not a
DT validator.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Tested-by: Liviu Dudau <liviu.dudau@arm.com>
Tested-by: Eric Anholt <eric@anholt.net>
Tested-by: Jyri Sarha <jsarha@ti.com>
Tested by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>

1 files changed, 3 insertions, 19 deletions

diff --git a/drivers/gpu/drm/arm/hdlcd_drv.c b/drivers/gpu/drm/arm/hdlcd_drv.c
index 0e74880b5e94..0f49c4b12772 100644
--- a/drivers/gpu/drm/arm/hdlcd_drv.c
+++ b/drivers/gpu/drm/arm/hdlcd_drv.c
@@ -392,29 +392,13 @@ static int compare_dev(struct device *dev, void *data)
 
 static int hdlcd_probe(struct platform_device *pdev)
 {
-	struct device_node *port, *ep;
+	struct device_node *port;
 	struct component_match *match = NULL;
 
-	if (!pdev->dev.of_node)
-		return -ENODEV;
-
 	/* there is only one output port inside each device, find it */
-	ep = of_graph_get_next_endpoint(pdev->dev.of_node, NULL);
-	if (!ep)
-		return -ENODEV;
-
-	if (!of_device_is_available(ep)) {
-		of_node_put(ep);
+	port = of_graph_get_remote_node(pdev->dev.of_node, 0, 0);
+	if (!port)
 		return -ENODEV;
-	}
-
-	/* add the remote encoder port as component */
-	port = of_graph_get_remote_port_parent(ep);
-	of_node_put(ep);
-	if (!port || !of_device_is_available(port)) {
-		of_node_put(port);
-		return -EAGAIN;
-	}
 
 	drm_of_component_match_add(&pdev->dev, &match, compare_dev, port);
 	of_node_put(port);