ASoC: ak4642: enable to use MCKO as fixed rate output pin on DT

ak4642 chip can output clock via MCKO pin as audio reference clock.
This patch supports it on DT

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 21 insertions, 1 deletions

diff --git a/Documentation/devicetree/bindings/sound/ak4642.txt b/Documentation/devicetree/bindings/sound/ak4642.txt
index 623d4e70ae11..340784db6808 100644
--- a/Documentation/devicetree/bindings/sound/ak4642.txt
+++ b/Documentation/devicetree/bindings/sound/ak4642.txt
@@ -7,7 +7,14 @@ Required properties:
   - compatible : "asahi-kasei,ak4642" or "asahi-kasei,ak4643" or "asahi-kasei,ak4648"
   - reg : The chip select number on the I2C bus
 
-Example:
+Optional properties:
+
+  - #clock-cells :		common clock binding; shall be set to 0
+  - clocks :			common clock binding; MCKI clock
+  - clock-frequency :		common clock binding; frequency of MCKO
+  - clock-output-names :	common clock binding; MCKO clock name
+
+Example 1:
 
 &i2c {
 	ak4648: ak4648@0x12 {
@@ -15,3 +22,16 @@ Example:
 		reg = <0x12>;
 	};
 };
+
+Example 2:
+
+&i2c {
+	ak4643: codec@12 {
+		compatible = "asahi-kasei,ak4643";
+		reg = <0x12>;
+		#clock-cells = <0>;
+		clocks = <&audio_clock>;
+		clock-frequency = <12288000>;
+		clock-output-names = "ak4643_mcko";
+	};
+};