dt-bindings: display: convert samsung,ld9040 to DT Schema

v2:
  - drop use of spi-slave.yaml (Maxime)
  - added unevaluatedProperties (Maxime)
  - added type to width/height properties (Rob)
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200408195109.32692-23-sam@ravnborg.org

Documentation/devicetree/bindings/display/panel/samsung,ld9040.txt

-Samsung LD9040 AMOLED LCD parallel RGB panel with SPI control bus
-
-Required properties:
-  - compatible: "samsung,ld9040"
-  - reg: address of the panel on SPI bus
-  - vdd3-supply: core voltage supply
-  - vci-supply: voltage supply for analog circuits
-  - reset-gpios: a GPIO spec for the reset pin
-  - display-timings: timings for the connected panel according to [1]
-
-The panel must obey rules for SPI slave device specified in document [2].
-
-Optional properties:
-  - power-on-delay: delay after turning regulators on [ms]
-  - reset-delay: delay after reset sequence [ms]
-  - panel-width-mm: physical panel width [mm]
-  - panel-height-mm: physical panel height [mm]
-
-The device node can contain one 'port' child node with one child
-'endpoint' node, according to the bindings defined in [3]. This
-node should describe panel's video bus.
-
-[1]: Documentation/devicetree/bindings/display/panel/display-timing.txt
-[2]: Documentation/devicetree/bindings/spi/spi-bus.txt
-[3]: Documentation/devicetree/bindings/media/video-interfaces.txt
-
-Example:
-
-	lcd@0 {
-		compatible = "samsung,ld9040";
-		reg = <0>;
-		vdd3-supply = <&ldo7_reg>;
-		vci-supply = <&ldo17_reg>;
-		reset-gpios = <&gpy4 5 0>;
-		spi-max-frequency = <1200000>;
-		spi-cpol;
-		spi-cpha;
-		power-on-delay = <10>;
-		reset-delay = <10>;
-		panel-width-mm = <90>;
-		panel-height-mm = <154>;
-
-		display-timings {
-			timing {
-				clock-frequency = <23492370>;
-				hactive = <480>;
-				vactive = <800>;
-				hback-porch = <16>;
-				hfront-porch = <16>;
-				vback-porch = <2>;
-				vfront-porch = <28>;
-				hsync-len = <2>;
-				vsync-len = <1>;
-				hsync-active = <0>;
-				vsync-active = <0>;
-				de-active = <0>;
-				pixelclk-active = <0>;
-			};
-		};
-
-		port {
-			lcd_ep: endpoint {
-				remote-endpoint = <&fimd_dpi_ep>;
-			};
-		};
-	};

Documentation/devicetree/bindings/display/panel/samsung,ld9040.yaml

+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/display/panel/samsung,ld9040.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Samsung LD9040 AMOLED LCD parallel RGB panel with SPI control bus
+
+description: |
+  The panel must obey the rules for a SPI slave device as specified in
+  spi/spi-controller.yaml
+
+maintainers:
+  - Andrzej Hajda <a.hajda@samsung.com>
+
+allOf:
+  - $ref: panel-common.yaml#
+
+properties:
+  compatible:
+    const: samsung,ld9040
+
+  display-timings: true
+  port: true
+  reg: true
+  reset-gpios: true
+
+  vdd3-supply:
+    description: core voltage supply
+
+  vci-supply:
+    description: voltage supply for analog circuits
+
+  power-on-delay:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: delay after turning regulators on [ms]
+
+  reset-delay:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: delay after reset sequence [ms]
+
+  panel-width-mm:
+    description: physical panel width [mm]
+
+  panel-height-mm:
+    description: physical panel height [mm]
+
+required:
+  - compatible
+  - reg
+  - vdd3-supply
+  - vci-supply
+  - reset-gpios
+  - display-timings
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    spi {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        lcd@0 {
+            compatible = "samsung,ld9040";
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            reg = <0>;
+            vdd3-supply = <&ldo7_reg>;
+            vci-supply = <&ldo17_reg>;
+            reset-gpios = <&gpy4 5 0>;
+            spi-max-frequency = <1200000>;
+            spi-cpol;
+            spi-cpha;
+            power-on-delay = <10>;
+            reset-delay = <10>;
+            panel-width-mm = <90>;
+            panel-height-mm = <154>;
+
+            display-timings {
+                timing {
+                    clock-frequency = <23492370>;
+                    hactive = <480>;
+                    vactive = <800>;
+                    hback-porch = <16>;
+                    hfront-porch = <16>;
+                    vback-porch = <2>;
+                    vfront-porch = <28>;
+                    hsync-len = <2>;
+                    vsync-len = <1>;
+                    hsync-active = <0>;
+                    vsync-active = <0>;
+                    de-active = <0>;
+                    pixelclk-active = <0>;
+                };
+            };
+
+            port {
+                lcd_ep: endpoint {
+                    remote-endpoint = <&fimd_dpi_ep>;
+                };
+            };
+        };
+    };
+
+...