ARM: dts: sun7i: Enable S/PDIF on the Cubietruck

Enable the S/PDIF transmitter present on the Cubietruck.
Signed-off-by: NChristopher Spinrath <christopher.spinrath@rwth-aachen.de>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/boot/dts/sun7i-a20-cubietruck.dts

@@ -94,6 +94,24 @@
 		pinctrl-0 = <&mmc3_pwrseq_pin_cubietruck>;
 		reset-gpios = <&pio 7 9 GPIO_ACTIVE_LOW>; /* PH9 WIFI_EN */
 	};
+
+	sound {
+		compatible = "simple-audio-card";
+		simple-audio-card,name = "On-board SPDIF";
+
+		simple-audio-card,cpu {
+			sound-dai = <&spdif>;
+		};
+
+		simple-audio-card,codec {
+			sound-dai = <&spdif_out>;
+		};
+	};
+
+	spdif_out: spdif-out {
+		#sound-dai-cells = <0>;
+		compatible = "linux,spdif-dit";
+	};
 };
 
 &ahci {
@@ -301,6 +319,12 @@
 	status = "okay";
 };
 
+&spdif {
+	pinctrl-names = "default";
+	pinctrl-0 = <&spdif_tx_pins_a>;
+	status = "okay";
+};
+
 &uart0 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart0_pins_a>;