drm/imx: parallel-display: fix drm_panel support

The parallel-display driver used an undocumented, non-standard property
"fsl,panel" to optionally associate with a drm_panel device. This patch
fixes the driver to use the same OF graph bindings as the LDB driver
instead:

    parallel-display {
            compatible = "fsl,imx-parallel-display";
            ...

            port@1 {
                    reg = <1>;

                    parallel_out: endpoint {
                            remote_endpoint = <&panel_in>;
                    };
            };
    };

    panel {
            ...

            port {
                    panel_in: endpoint {
                            remote-endpoint = <&parallel_out>;
                    };
            };
    };

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Tested-by: Gary Bisson <gary.bisson@boundarydevices.com>

1 files changed, 24 insertions, 2 deletions

diff --git a/Documentation/devicetree/bindings/drm/imx/fsl-imx-drm.txt b/Documentation/devicetree/bindings/drm/imx/fsl-imx-drm.txt
index e75f0e549fff..971c3eedb1c7 100644
--- a/Documentation/devicetree/bindings/drm/imx/fsl-imx-drm.txt
+++ b/Documentation/devicetree/bindings/drm/imx/fsl-imx-drm.txt
@@ -65,8 +65,10 @@ Optional properties:
 - edid: verbatim EDID data block describing attached display.
 - ddc: phandle describing the i2c bus handling the display data
   channel
-- port: A port node with endpoint definitions as defined in
+- port@[0-1]: Port nodes with endpoint definitions as defined in
   Documentation/devicetree/bindings/media/video-interfaces.txt.
+  Port 0 is the input port connected to the IPU display interface,
+  port 1 is the output port connected to a panel.
 
 example:
 
@@ -75,9 +77,29 @@ display@di0 {
 	edid = [edid-data];
 	interface-pix-fmt = "rgb24";
 
-	port {
+	port@0 {
+		reg = <0>;
+
 		display_in: endpoint {
 			remote-endpoint = <&ipu_di0_disp0>;
 		};
 	};
+
+	port@1 {
+		reg = <1>;
+
+		display_out: endpoint {
+			remote-endpoint = <&panel_in>;
+		};
+	};
+};
+
+panel {
+	...
+
+	port {
+		panel_in: endpoint {
+			remote-endpoint = <&display_out>;
+		};
+	};
 };