dt-bindings: display: Add ingenic,jz4780-dw-hdmi DT Schema

Add DT bindings for the hdmi driver for the Ingenic JZ4780 SoC.
Based on .txt binding from Zubair Lutfullah Kakakhel
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
Cc: Rob Herring <robh@kernel.org>
Cc: devicetree@vger.kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Link: https://patchwork.freedesktop.org/patch/msgid/c806c6007f7bb090bf96ff6bd827f03e88bf4712.1644675566.git.hns@goldelico.com

Documentation/devicetree/bindings/display/bridge/ingenic,jz4780-hdmi.yaml

+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/bridge/ingenic,jz4780-hdmi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Bindings for Ingenic JZ4780 HDMI Transmitter
+
+maintainers:
+  - H. Nikolaus Schaller <hns@goldelico.com>
+
+description: |
+  The HDMI Transmitter in the Ingenic JZ4780 is a Synopsys DesignWare HDMI 1.4
+  TX controller IP with accompanying PHY IP.
+
+allOf:
+  - $ref: synopsys,dw-hdmi.yaml#
+
+properties:
+  compatible:
+    const: ingenic,jz4780-dw-hdmi
+
+  reg-io-width:
+    const: 4
+
+  clocks:
+    maxItems: 2
+
+  ports:
+    $ref: /schemas/graph.yaml#/properties/ports
+
+    properties:
+      port@0:
+        $ref: /schemas/graph.yaml#/properties/port
+        description: Input from LCD controller output.
+
+      port@1:
+        $ref: /schemas/graph.yaml#/properties/port
+        description: Link to the HDMI connector.
+
+required:
+  - compatible
+  - clocks
+  - clock-names
+  - ports
+  - reg-io-width
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/ingenic,jz4780-cgu.h>
+
+    hdmi: hdmi@10180000 {
+        compatible = "ingenic,jz4780-dw-hdmi";
+        reg = <0x10180000 0x8000>;
+        reg-io-width = <4>;
+        ddc-i2c-bus = <&i2c4>;
+        interrupt-parent = <&intc>;
+        interrupts = <3>;
+        clocks = <&cgu JZ4780_CLK_AHB0>, <&cgu JZ4780_CLK_HDMI>;
+        clock-names = "iahb", "isfr";
+
+        ports {
+            #address-cells = <1>;
+            #size-cells = <0>;
+            hdmi_in: port@0 {
+                reg = <0>;
+                dw_hdmi_in: endpoint {
+                    remote-endpoint = <&jz4780_lcd_out>;
+                };
+            };
+            hdmi_out: port@1 {
+                reg = <1>;
+                dw_hdmi_out: endpoint {
+                    remote-endpoint = <&hdmi_con>;
+                };
+            };
+        };
+    };
+
+...