simple-mux immediately activates the new output, even when it is powered
down. This can be undesirable in some cases, for example when a
mechanical relais is used.
Adds "idle-state" property from the mux controller to select the output
state to be used when the mux is powered down.

Signed-off-by: Hendrik v. Raven <h.v.raven@merzmedtech.de>
---
 Documentation/devicetree/bindings/sound/simple-audio-mux.yaml | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/sound/simple-audio-mux.yaml b/Documentation/devicetree/bindings/sound/simple-audio-mux.yaml
index 194ac1d4f4f5f40a9bc44e8cd0acbf2eab708365..9b1bda4852e160618ffd349d2f7c90645d5b3e03 100644
--- a/Documentation/devicetree/bindings/sound/simple-audio-mux.yaml
+++ b/Documentation/devicetree/bindings/sound/simple-audio-mux.yaml
@@ -29,6 +29,10 @@ properties:
     $ref: /schemas/types.yaml#/definitions/string-array
     maxItems: 2
 
+  idle-state:
+    description: If present specifies the state when the mux is powered down
+    $ref: /schemas/mux/mux-controller.yaml#/properties/idle-state
+
   sound-name-prefix: true
 
 required:
@@ -43,4 +47,5 @@ examples:
         compatible = "simple-audio-mux";
         mux-gpios = <&gpio 3 0>;
         state-labels = "Label_A", "Label_B";
+        idle-state = <0>;
     };

-- 
2.47.0