arm64: dts: allwinner: Add SPDIF node for Allwinner H6

The Allwinner H6 has a SPDIF controller called OWA (One Wire Audio).

Only one pinmuxing is available so set it as default.
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>

arch/arm64/boot/dts/allwinner/sun50i-h6.dtsi

@@ -282,6 +282,11 @@ mmc2_pins: mmc2-pins {
 				bias-pull-up;
 			};
 
+			spdif_tx_pin: spdif-tx-pin {
+				pins = "PH7";
+				function = "spdif";
+			};
+
 			uart0_ph_pins: uart0-ph-pins {
 				pins = "PH0", "PH1";
 				function = "uart0";
@@ -411,6 +416,21 @@ mdio: mdio {
 			};
 		};
 
+		spdif: spdif@5093000 {
+			#sound-dai-cells = <0>;
+			compatible = "allwinner,sun50i-h6-spdif";
+			reg = <0x05093000 0x400>;
+			interrupts = <GIC_SPI 21 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&ccu CLK_BUS_SPDIF>, <&ccu CLK_SPDIF>;
+			clock-names = "apb", "spdif";
+			resets = <&ccu RST_BUS_SPDIF>;
+			dmas = <&dma 2>;
+			dma-names = "tx";
+			pinctrl-names = "default";
+			pinctrl-0 = <&spdif_tx_pin>;
+			status = "disabled";
+		};
+
 		usb2otg: usb@5100000 {
 			compatible = "allwinner,sun50i-h6-musb",
 				     "allwinner,sun8i-a33-musb";