arm64: dts: mediatek: asurada: Add system-wide power supplies

Add system-wide power supplies present on all of the boards in the
Asurada family.
Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220629155956.1138955-6-nfraprado@collabora.comSigned-off-by: Matthias Brugger <matthias.bgg@gmail.com>

arch/arm64/boot/dts/mediatek/mt8192-asurada.dtsi

@@ -19,6 +19,70 @@ memory@40000000 {
 		device_type = "memory";
 		reg = <0 0x40000000 0 0x80000000>;
 	};
+
+	/* system wide LDO 1.8V power rail */
+	pp1800_ldo_g: regulator-1v8-g {
+		compatible = "regulator-fixed";
+		regulator-name = "pp1800_ldo_g";
+		regulator-always-on;
+		regulator-boot-on;
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <1800000>;
+		vin-supply = <&pp3300_g>;
+	};
+
+	/* system wide switching 3.3V power rail */
+	pp3300_g: regulator-3v3-g {
+		compatible = "regulator-fixed";
+		regulator-name = "pp3300_g";
+		regulator-always-on;
+		regulator-boot-on;
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		vin-supply = <&ppvar_sys>;
+	};
+
+	/* system wide LDO 3.3V power rail */
+	pp3300_ldo_z: regulator-3v3-z {
+		compatible = "regulator-fixed";
+		regulator-name = "pp3300_ldo_z";
+		regulator-always-on;
+		regulator-boot-on;
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		vin-supply = <&ppvar_sys>;
+	};
+
+	/* separately switched 3.3V power rail */
+	pp3300_u: regulator-3v3-u {
+		compatible = "regulator-fixed";
+		regulator-name = "pp3300_u";
+		regulator-always-on;
+		regulator-boot-on;
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		/* enable pin wired to GPIO controlled by EC */
+		vin-supply = <&pp3300_g>;
+	};
+
+	/* system wide switching 5.0V power rail */
+	pp5000_a: regulator-5v0-a {
+		compatible = "regulator-fixed";
+		regulator-name = "pp5000_a";
+		regulator-always-on;
+		regulator-boot-on;
+		regulator-min-microvolt = <5000000>;
+		regulator-max-microvolt = <5000000>;
+		vin-supply = <&ppvar_sys>;
+	};
+
+	/* system wide semi-regulated power rail from battery or USB */
+	ppvar_sys: regulator-var-sys {
+		compatible = "regulator-fixed";
+		regulator-name = "ppvar_sys";
+		regulator-always-on;
+		regulator-boot-on;
+	};
 };
 
 &pio {