ASoC: dt-bindings: Convert Allwinner A64 analog codec to a schema

The Allwinner A64 SoC has an embedded audio codec that uses a separate
controller to drive its analog part, which is supported in Linux, with a
matching Device Tree binding.

Now that we have the DT validation in place, let's convert the device tree
bindings for that controller over to a YAML schemas.
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://lore.kernel.org/r/20190828125209.28173-5-mripard@kernel.orgReviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/allwinner,sun50i-a64-codec-analog.yaml

+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/sound/allwinner,sun50i-a64-codec-analog.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner A64 Analog Codec Device Tree Bindings
+
+maintainers:
+  - Chen-Yu Tsai <wens@csie.org>
+  - Maxime Ripard <maxime.ripard@bootlin.com>
+
+properties:
+  compatible:
+    const: allwinner,sun50i-a64-codec-analog
+
+  reg:
+    maxItems: 1
+
+  cpvdd-supply:
+    description:
+      Regulator for the headphone amplifier
+
+required:
+  - compatible
+  - reg
+  - cpvdd-supply
+
+additionalProperties: false
+
+examples:
+  - |
+    codec_analog: codec-analog@1f015c0 {
+      compatible = "allwinner,sun50i-a64-codec-analog";
+      reg = <0x01f015c0 0x4>;
+      cpvdd-supply = <&reg_eldo1>;
+    };
+
+...

Documentation/devicetree/bindings/sound/sun50i-codec-analog.txt

-* Allwinner A64 Codec Analog Controls
-
-Required properties:
-- compatible: must be one of the following compatibles:
-		- "allwinner,sun50i-a64-codec-analog"
-- reg: must contain the registers location and length
-- cpvdd-supply: Regulator supply for the headphone amplifier
-
-Example:
-	codec_analog: codec-analog@1f015c0 {
-		compatible = "allwinner,sun50i-a64-codec-analog";
-		reg = <0x01f015c0 0x4>;
-		cpvdd-supply = <&reg_eldo1>;
-	};