ASoC: spdif_receiver: Add DT support.

Add devicetree support for this dummy audio soc driver.

Signed-off-by: Michal Bachraty <michal.bachraty@streamunlimited.com>
Signed-off-by: Marek Belisko <marek.belisko@streamunlimited.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/Documentation/devicetree/bindings/sound/spdif-receiver.txt b/Documentation/devicetree/bindings/sound/spdif-receiver.txt
new file mode 100644
index 0000000..80f807b
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/spdif-receiver.txt
@@ -0,0 +1,10 @@
+Device-Tree bindings for dummy spdif receiver
+
+Required properties:
+	- compatible: should be "linux,spdif-dir".
+
+Example node:
+
+	codec: spdif-receiver {
+		compatible = "linux,spdif-dir";
+	};