ASoC: tfa9879: Add device tree bindings

Even though the tfa9879 driver can probe via device tree trough the
I2C core code, it is preferable to have explicit device tree
bindings instead [1], so add this support.

[1] https://www.spinics.net/lists/devicetree/msg195176.html

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Łukasz Majewski <lukma@denx.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

2 files changed, 29 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/sound/tfa9879.txt b/Documentation/devicetree/bindings/sound/tfa9879.txt
new file mode 100644
index 000000000000..23ba522d9e2b
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/tfa9879.txt
@@ -0,0 +1,23 @@
+NXP TFA9879 class-D audio amplifier
+
+Required properties:
+
+- compatible : "nxp,tfa9879"
+
+- reg : the I2C address of the device
+
+Example:
+
+&i2c1 {
+        clock-frequency = <100000>;
+        pinctrl-names = "default";
+        pinctrl-0 = <&pinctrl_i2c1>;
+        status = "okay";
+
+        codec: tfa9879@6c {
+                #sound-dai-cells = <0>;
+                compatible = "nxp,tfa9879";
+                reg = <0x6c>;
+        };
+};
+
diff --git a/sound/soc/codecs/tfa9879.c b/sound/soc/codecs/tfa9879.c
index 95e0a7abeb7a..f8dd67ca0744 100644
--- a/sound/soc/codecs/tfa9879.c
+++ b/sound/soc/codecs/tfa9879.c
@@ -312,9 +312,15 @@ static const struct i2c_device_id tfa9879_i2c_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, tfa9879_i2c_id);
 
+static const struct of_device_id tfa9879_of_match[] = {
+        { .compatible = "nxp,tfa9879", },
+        { }
+};
+
 static struct i2c_driver tfa9879_i2c_driver = {
         .driver = {
                 .name = "tfa9879",
+                .of_match_table = tfa9879_of_match,
         },
         .probe = tfa9879_i2c_probe,
         .remove = tfa9879_i2c_remove,