dt-bindings: pwm: Convert pwm-mtk-disp.txt to mediatek,pwm-disp.yaml format

Convert pwm-mtk-disp.txt to mediatek,pwm-disp.yaml format as suggested
by maintainer.
Signed-off-by: Xinlei Lee <xinlei.lee@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Miles Chen <miles.chen@mediatek.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

Documentation/devicetree/bindings/pwm/mediatek,pwm-disp.yaml

+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pwm/mediatek,pwm-disp.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek DISP_PWM Controller Device Tree Bindings
+
+maintainers:
+  - Jitao Shi <jitao.shi@mediatek.com>
+  - Xinlei Lee <xinlei.lee@mediatek.com>
+
+allOf:
+  - $ref: pwm.yaml#
+
+properties:
+  compatible:
+    oneOf:
+      - enum:
+          - mediatek,mt2701-disp-pwm
+          - mediatek,mt6595-disp-pwm
+          - mediatek,mt8173-disp-pwm
+          - mediatek,mt8183-disp-pwm
+      - items:
+          - const: mediatek,mt8167-disp-pwm
+          - const: mediatek,mt8173-disp-pwm
+
+  reg:
+    maxItems: 1
+
+  "#pwm-cells":
+    const: 2
+
+  clocks:
+    items:
+      - description: Main Clock
+      - description: Mm Clock
+
+  clock-names:
+    items:
+      - const: main
+      - const: mm
+
+required:
+  - compatible
+  - reg
+  - "#pwm-cells"
+  - clocks
+  - clock-names
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/clock/mt8173-clk.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    pwm0: pwm@1401e000 {
+        compatible = "mediatek,mt8173-disp-pwm";
+        reg = <0x1401e000 0x1000>;
+        #pwm-cells = <2>;
+        clocks = <&mmsys CLK_MM_DISP_PWM026M>,
+                 <&mmsys CLK_MM_DISP_PWM0MM>;
+        clock-names = "main", "mm";
+    };

Documentation/devicetree/bindings/pwm/pwm-mtk-disp.txt

-MediaTek display PWM controller
-
-Required properties:
- - compatible: should be "mediatek,<name>-disp-pwm":
-   - "mediatek,mt2701-disp-pwm": found on mt2701 SoC.
-   - "mediatek,mt6595-disp-pwm": found on mt6595 SoC.
-   - "mediatek,mt8167-disp-pwm", "mediatek,mt8173-disp-pwm": found on mt8167 SoC.
-   - "mediatek,mt8173-disp-pwm": found on mt8173 SoC.
-   - "mediatek,mt8183-disp-pwm": found on mt8183 SoC.$
- - reg: physical base address and length of the controller's registers.
- - #pwm-cells: must be 2. See pwm.yaml in this directory for a description of
-   the cell format.
- - clocks: phandle and clock specifier of the PWM reference clock.
- - clock-names: must contain the following:
-   - "main": clock used to generate PWM signals.
-   - "mm": sync signals from the modules of mmsys.
- - pinctrl-names: Must contain a "default" entry.
- - pinctrl-0: One property must exist for each entry in pinctrl-names.
-   See pinctrl/pinctrl-bindings.txt for details of the property values.
-
-Example:
-	pwm0: pwm@1401e000 {
-		compatible = "mediatek,mt8173-disp-pwm",
-			     "mediatek,mt6595-disp-pwm";
-		reg = <0 0x1401e000 0 0x1000>;
-		#pwm-cells = <2>;
-		clocks = <&mmsys CLK_MM_DISP_PWM026M>,
-			 <&mmsys CLK_MM_DISP_PWM0MM>;
-		clock-names = "main", "mm";
-		pinctrl-names = "default";
-		pinctrl-0 = <&disp_pwm0_pins>;
-	};
-
-	backlight_lcd: backlight_lcd {
-		compatible = "pwm-backlight";
-		pwms = <&pwm0 0 1000000>;
-		brightness-levels = <
-			  0  16  32  48  64  80  96 112
-			128 144 160 176 192 208 224 240
-			255
-		>;
-		default-brightness-level = <9>;
-		power-supply = <&mt6397_vio18_reg>;
-		enable-gpios = <&pio 95 GPIO_ACTIVE_HIGH>;
-	};