Add mute-gpio to ssm2602

Signed-off-by: Paweł Anikiel <pan@semihalf.com>
---
 Documentation/devicetree/bindings/sound/adi,ssm2602.txt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/sound/adi,ssm2602.txt b/Documentation/devicetree/bindings/sound/adi,ssm2602.txt
index 3b3302fe399b..132aa9668e7e 100644
--- a/Documentation/devicetree/bindings/sound/adi,ssm2602.txt
+++ b/Documentation/devicetree/bindings/sound/adi,ssm2602.txt
@@ -11,6 +11,10 @@ Required properties:
   - reg : the I2C address of the device for I2C, the chip select
           number for SPI.
 
+Optional properties:
+
+- mute-gpios: GPIO specifier for the mute pin
+
  Example:
 
 	ssm2602: ssm2602@1a {
-- 
2.40.0.634.g4ca3ef3211-goog