ASoC: dt-bindings: aw87390: Add Anbernic RG-DS Amplifier

Add a binding for the Anbernic RG-DS Amplifier, which is an Awinic
aw87391 audio amplifier. This manufacturer did not provide firmware
so we have to use a list of init commands instead, requiring device
specific functionality rather than generic aw87391 functionality.

Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20260128174608.1498-2-macroalpha82@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/awinic,aw87390.yaml

@@ -15,12 +15,15 @@ description:
   sound quallity, which is a new high efficiency, low
   noise, constant large volume, 6th Smart K audio amplifier.
 
-allOf:
-  - $ref: dai-common.yaml#
-
 properties:
   compatible:
-    const: awinic,aw87390
+    oneOf:
+      - enum:
+          - awinic,aw87390
+      - items:
+          - enum:
+              - anbernic,rgds-amp
+          - const: awinic,aw87391
 
   reg:
     maxItems: 1
@@ -40,10 +43,31 @@ required:
   - compatible
   - reg
   - "#sound-dai-cells"
-  - awinic,audio-channel
 
 unevaluatedProperties: false
 
+allOf:
+  - $ref: dai-common.yaml#
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - awinic,aw87390
+    then:
+      required:
+        - awinic,audio-channel
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - anbernic,rgds-amp
+    then:
+      properties:
+        vdd-supply: true
+
 examples:
   - |
     i2c {