dt-bindings: sound: add dmicen property in dmic driver

there may use enable pin to control dmic start and stop,
so add this property in dt-bindings.

Signed-off-by: Lin Huang <hl@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/Documentation/devicetree/bindings/sound/dmic.txt b/Documentation/devicetree/bindings/sound/dmic.txt
index a0c58f2a162a4d28710f10cb840f6f2390c3995a..54c8ef6498a87d26b830cfe3ed69543c2b97ae12 100644 (file)
--- a/Documentation/devicetree/bindings/sound/dmic.txt
+++ b/Documentation/devicetree/bindings/sound/dmic.txt
@@ -5,8 +5,12 @@ This device support generic PDM digital microphone.
 Required properties:
        - compatible: should be "dmic-codec".
 
+Optional properties:
+       - dmicen-gpios: GPIO specifier for dmic to control start and stop
+
 Example node:
 
        dmic_codec: dmic@0 {
                compatible = "dmic-codec";
+               dmicen-gpios = <&gpio4 3 GPIO_ACTIVE_HIGH>;
        };