arm64: dts: rockchip: add sdmmc UHS support for roc-rk3328-cc

In roc-rk3328-cc board, the signal voltage of sdmmc is supplied by the
vcc_sdio regulator, which is a mux between 1.8V and 3.3V, controlled by
a special output only gpio pin labeled "gpiomut_pmuio_iout",
corresponding bit 1 of the syscon GRF_SOC_CON10.

This special pin can now be reference as <&grf_gpio 0>, thanks to the
gpio-syscon driver, which makes writing regulator-gpio possible.

If the signal voltage changes, the io domain needs to change
correspondingly.

To use this feature, the following options are required in kernel config:
 - CONFIG_GPIO_SYSCON=y
 - CONFIG_POWER_AVS=y
 - CONFIG_ROCKCHIP_IODOMAIN=y

Signed-off-by: Levin Du <djw@t-chip.com.cn>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3328-roc-cc.dts

@@ -41,6 +41,19 @@
 		vin-supply = <&vcc_io>;
 	};
 
+	vcc_sdio: sdmmcio-regulator {
+		compatible = "regulator-gpio";
+		gpios = <&grf_gpio 0 GPIO_ACTIVE_HIGH>;
+		states = <1800000 0x1
+			  3300000 0x0>;
+		regulator-name = "vcc_sdio";
+		regulator-type = "voltage";
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <3300000>;
+		regulator-always-on;
+		vin-supply = <&vcc_sys>;
+	};
+
 	vcc_host1_5v: vcc_otg_5v: vcc-host1-5v-regulator {
 		compatible = "regulator-fixed";
 		enable-active-high;
@@ -213,7 +226,7 @@
 
 	vccio1-supply = <&vcc_io>;
 	vccio2-supply = <&vcc18_emmc>;
-	vccio3-supply = <&vcc_io>;
+	vccio3-supply = <&vcc_sdio>;
 	vccio4-supply = <&vcc_18>;
 	vccio5-supply = <&vcc_io>;
 	vccio6-supply = <&vcc_io>;
@@ -242,7 +255,12 @@
 	max-frequency = <150000000>;
 	pinctrl-names = "default";
 	pinctrl-0 = <&sdmmc0_clk &sdmmc0_cmd &sdmmc0_dectn &sdmmc0_bus4>;
+	sd-uhs-sdr12;
+	sd-uhs-sdr25;
+	sd-uhs-sdr50;
+	sd-uhs-sdr104;
 	vmmc-supply = <&vcc_sd>;
+	vqmmc-supply = <&vcc_sdio>;
 	status = "okay";
 };