ARM: dts: rockchip: Add the iodomains for the Rock2 SOM

Add the IO domain configuration for the Rock2 SOM and model the fixed
regulator used as the vqmmc for the EMMC device.
Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm/boot/dts/rk3288-rock2-som.dtsi

@@ -61,6 +61,31 @@ ext_gmac: external-gmac-clock {
 		clock-output-names = "ext_gmac";
 	};
 
+	io_domains: io-domains {
+		compatible = "rockchip,rk3288-io-voltage-domain";
+		rockchip,grf = <&grf>;
+
+		audio-supply = <&vcc_io>;
+		bb-supply = <&vcc_io>;
+		dvp-supply = <&vcc_18>;
+		flash0-supply = <&vcc_flash>;
+		flash1-supply = <&vccio_pmu>;
+		gpio30-supply = <&vccio_pmu>;
+		gpio1830 = <&vcc_io>;
+		lcdc-supply = <&vcc_io>;
+		sdcard-supply = <&vccio_sd>;
+		wifi-supply = <&vcc_18>;
+	};
+
+	vcc_flash: flash-regulator {
+		compatible = "regulator-fixed";
+		regulator-name = "vcc_sys";
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <1800000>;
+		startup-delay-us = <150>;
+		vin-supply = <&vcc_io>;
+	};
+
 	vcc_sys: vsys-regulator {
 		compatible = "regulator-fixed";
 		regulator-name = "vcc_sys";
@@ -85,6 +110,7 @@ &emmc {
 	pinctrl-names = "default";
 	pinctrl-0 = <&emmc_clk &emmc_cmd &emmc_bus8>;
 	vmmc-supply = <&vcc_io>;
+	vqmmc-supply = <&vcc_flash>;
 	status = "okay";
 };