ASoC: dt-bindings: Convert Allwinner A23 analog codec to a schema

The Allwinner A23 SoC and later have 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>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20190906151221.3148-2-mripard@kernel.orgSigned-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/allwinner,sun8i-a23-codec-analog.yaml

+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/sound/allwinner,sun8i-a23-codec-analog.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Allwinner A23 Analog Codec Device Tree Bindings
+
+maintainers:
+  - Chen-Yu Tsai <wens@csie.org>
+  - Maxime Ripard <maxime.ripard@bootlin.com>
+
+properties:
+  compatible:
+    enum:
+      # FIXME: This is documented in the PRCM binding, but needs to be
+      # migrated here at some point
+      # - allwinner,sun8i-a23-codec-analog
+      - allwinner,sun8i-h3-codec-analog
+      - allwinner,sun8i-v3s-codec-analog
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    codec_analog: codec-analog@1f015c0 {
+      compatible = "allwinner,sun8i-h3-codec-analog";
+      reg = <0x01f015c0 0x4>;
+    };
+
+...

Documentation/devicetree/bindings/sound/sun8i-codec-analog.txt

-* Allwinner Codec Analog Controls
-
-Required properties:
-- compatible: must be one of the following compatibles:
-		- "allwinner,sun8i-a23-codec-analog"
-		- "allwinner,sun8i-h3-codec-analog"
-		- "allwinner,sun8i-v3s-codec-analog"
-
-Required properties if not a sub-node of the PRCM node:
-- reg: must contain the registers location and length
-
-Example:
-prcm: prcm@1f01400 {
-	codec_analog: codec-analog {
-		compatible = "allwinner,sun8i-a23-codec-analog";
-	};
-};