[PATCH v2 2/2] ASoC: dt-bindings: asahi-kasei,ak4619: Add powerdown GPIO

[Alexander Koch <mail@alexanderkoch.net>]

Add documentation for an optional property that enables operation of the
'PDN' (powerdown) pin during initialization:

    codec@10 {
        compatible = "asahi-kasei,ak4619";
        reg = <0x10>;
        powerdown-gpios = <&gpio1 0 GPIO_ACTIVE_LOW>;  // <--
        #sound-dai-cells = <0>;
    };

Signed-off-by: Alexander Koch <mail@alexanderkoch.net>
---
 .../devicetree/bindings/sound/asahi-kasei,ak4619.yaml  | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Documentation/devicetree/bindings/sound/asahi-kasei,ak4619.yaml b/Documentation/devicetree/bindings/sound/asahi-kasei,ak4619.yaml
index d412531ef9a2..86e0b8cbfc29 100644
--- a/Documentation/devicetree/bindings/sound/asahi-kasei,ak4619.yaml
+++ b/Documentation/devicetree/bindings/sound/asahi-kasei,ak4619.yaml
@@ -34,6 +34,12 @@ properties:
     $ref: audio-graph-port.yaml#
     unevaluatedProperties: false
 
+  powerdown-gpios:
+    maxItems: 1
+    description:
+      GPIO connected to the 'PDN' pin, if any. Needs to be set low to
+      power down the codec, hence the GPIO must be GPIO_ACTIVE_LOW.
+
 required:
   - compatible
   - reg
@@ -42,6 +48,8 @@ unevaluatedProperties: false
 
 examples:
   - |
+    #include <dt-bindings/gpio/gpio.h>
+
     i2c {
         #address-cells = <1>;
         #size-cells = <0>;
@@ -49,6 +57,8 @@ examples:
             compatible = "asahi-kasei,ak4619";
             reg = <0x10>;
 
+            powerdown-gpios = <&gpio1 0 GPIO_ACTIVE_LOW>;
+
             clocks = <&rcar_sound>;
             clock-names = "mclk";
 
-- 
2.55.0