arm64: dts: mediatek: cherry: Configure eDP and internal display

Add the required nodes to enable the DisplayPort interface, connected
to the Embedded DisplayPort port, where we have an internal display.

Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20230816190427.2137768-1-nfraprado@collabora.com
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>

Author: AngeloGioacchino Del Regno

arch/arm64/boot/dts/mediatek/mt8195-cherry.dtsi

@@ -47,6 +47,19 @@
 		reg = <0 0x40000000 0 0x80000000>;
 	};
 
+	pp3300_disp_x: regulator-pp3300-disp-x {
+		compatible = "regulator-fixed";
+		regulator-name = "pp3300_disp_x";
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		regulator-enable-ramp-delay = <2500>;
+		enable-active-high;
+		gpio = <&pio 55 GPIO_ACTIVE_HIGH>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&panel_fixed_pins>;
+		vin-supply = <&pp3300_z2>;
+	};
+
 	/* system wide LDO 3.3V power rail */
 	pp3300_z5: regulator-pp3300-ldo-z5 {
 		compatible = "regulator-fixed";
@@ -217,6 +230,20 @@
 			reg = <1>;
 			edp_out: endpoint {
 				data-lanes = <0 1 2 3>;
+				remote-endpoint = <&panel_in>;
+			};
+		};
+	};
+
+	aux-bus {
+		panel {
+			compatible = "edp-panel";
+			power-supply = <&pp3300_disp_x>;
+			backlight = <&backlight_lcd0>;
+			port {
+				panel_in: endpoint {
+					remote-endpoint = <&edp_out>;
+				};
 			};
 		};
 	};
@@ -881,6 +908,12 @@
 		};
 	};
 
+	panel_fixed_pins: panel-pwr-default-pins {
+		pins-vreg-en {
+			pinmux = <PINMUX_GPIO55__FUNC_GPIO55>;
+		};
+	};
+
 	pio_default: pio-default-pins {
 		pins-wifi-enable {
 			pinmux = <PINMUX_GPIO58__FUNC_GPIO58>;