ARM: dts: rockchip: add eDP/panel display device nodes for rk3288-evb

The default eDP panel on RK3288 EVB board is LG LP079QX1-SP0V TFT LCD,
we haven't declared the panel regulator in the 'panel-simple' device
node here, so the specific board like ACT8846 / RK8080 need to support
the panel power supply.
Signed-off-by: Yakir Yang <ykk@rock-chips.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

arch/arm/boot/dts/rk3288-evb.dtsi

@@ -48,7 +48,7 @@ memory {
 		reg = <0x0 0x80000000>;
 	};
 
-	backlight {
+	backlight: backlight {
 		compatible = "pwm-backlight";
 		brightness-levels = <
 			  0   1   2   3   4   5   6   7
@@ -97,6 +97,21 @@ ext_gmac: external-gmac-clock {
 		#clock-cells = <0>;
 	};
 
+	panel: panel {
+		compatible ="lg,lp079qx1-sp0v", "simple-panel";
+		backlight = <&backlight>;
+		enable-gpios = <&gpio7 4 GPIO_ACTIVE_HIGH>;
+		pinctrl-0 = <&lcd_cs>;
+
+		ports {
+			panel_in: port {
+				panel_in_edp: endpoint {
+					remote-endpoint = <&edp_out_panel>;
+				};
+			};
+		};
+	};
+
 	gpio-keys {
 		compatible = "gpio-keys";
 		autorepeat;
@@ -170,6 +185,28 @@ &cpu0 {
 	cpu0-supply = <&vdd_cpu>;
 };
 
+&edp {
+	force-hpd;
+	status = "okay";
+
+	ports {
+		edp_out: port@1 {
+			reg = <1>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			edp_out_panel: endpoint {
+				reg = <0>;
+				remote-endpoint = <&panel_in_edp>;
+			};
+		};
+	};
+};
+
+&edp_phy {
+	status = "okay";
+};
+
 &emmc {
 	bus-width = <8>;
 	cap-mmc-highspeed;
@@ -280,6 +317,12 @@ pwrbtn: pwrbtn {
 		};
 	};
 
+	lcd {
+		lcd_cs: lcd-cs {
+			rockchip,pins = <7 4 RK_FUNC_GPIO &pcfg_pull_none>;
+		};
+	};
+
 	pmic {
 		pmic_int: pmic-int {
 			rockchip,pins = <RK_GPIO0 4 RK_FUNC_GPIO &pcfg_pull_up>;