Samsung LD9040 AMOLED LCD parallel RGB panel with SPI control bus

Required properties:
  - compatible: "samsung,ld9040"
  - reg: address of the panel on SPI bus
  - vdd3-supply: core voltage supply
  - vci-supply: voltage supply for analog circuits
  - reset-gpios: a GPIO spec for the reset pin
  - display-timings: timings for the connected panel according to [1]

The panel must obey rules for SPI slave device specified in document [2].

Optional properties:
  - power-on-delay: delay after turning regulators on [ms]
  - reset-delay: delay after reset sequence [ms]
  - panel-width-mm: physical panel width [mm]
  - panel-height-mm: physical panel height [mm]

The device node can contain one 'port' child node with one child
'endpoint' node, according to the bindings defined in [3]. This
node should describe panel's video bus.

[1]: Documentation/devicetree/bindings/display/display-timing.txt
[2]: Documentation/devicetree/bindings/spi/spi-bus.txt
[3]: Documentation/devicetree/bindings/media/video-interfaces.txt

Example:

	lcd@0 {
		compatible = "samsung,ld9040";
		reg = <0>;
		vdd3-supply = <&ldo7_reg>;
		vci-supply = <&ldo17_reg>;
		reset-gpios = <&gpy4 5 0>;
		spi-max-frequency = <1200000>;
		spi-cpol;
		spi-cpha;
		power-on-delay = <10>;
		reset-delay = <10>;
		panel-width-mm = <90>;
		panel-height-mm = <154>;

		display-timings {
			timing {
				clock-frequency = <23492370>;
				hactive = <480>;
				vactive = <800>;
				hback-porch = <16>;
				hfront-porch = <16>;
				vback-porch = <2>;
				vfront-porch = <28>;
				hsync-len = <2>;
				vsync-len = <1>;
				hsync-active = <0>;
				vsync-active = <0>;
				de-active = <0>;
				pixelclk-active = <0>;
			};
		};

		port {
			lcd_ep: endpoint {
				remote-endpoint = <&fimd_dpi_ep>;
			};
		};
	};