The Exynos display port interface should be configured based on
the type of panel connected to it.

We use two nodes:
	-dp-controller node
	-dptx-phy node(defined inside dp-controller node)

For the DP-PHY initialization, we use the dptx-phy node.
Required properties for dptx-phy:
	-reg:
		Base address of DP PHY register.
	-samsung,enable-mask:
		The bit-mask used to enable/disable DP PHY.

For the Panel initialization, we read data from dp-controller node.
Required properties for dp-controller:
	-compatible:
		should be "samsung,exynos5-dp".
	-reg:
		physical base address of the controller and length
		of memory mapped region.
	-interrupts:
		interrupt combiner values.
	-interrupt-parent:
		phandle to Interrupt combiner node.
	-samsung,color-space:
		input video data format.
			COLOR_RGB = 0, COLOR_YCBCR422 = 1, COLOR_YCBCR444 = 2
	-samsung,dynamic-range:
		dynamic range for input video data.
			VESA = 0, CEA = 1
	-samsung,ycbcr-coeff:
		YCbCr co-efficients for input video.
			COLOR_YCBCR601 = 0, COLOR_YCBCR709 = 1
	-samsung,color-depth:
		number of bits per colour component.
			COLOR_6 = 0, COLOR_8 = 1, COLOR_10 = 2, COLOR_12 = 3
	-samsung,link-rate:
		link rate supported by the panel.
			LINK_RATE_1_62GBPS = 0x6, LINK_RATE_2_70GBPS = 0x0A
	-samsung,lane-count:
		number of lanes supported by the panel.
			LANE_COUNT1 = 1, LANE_COUNT2 = 2, LANE_COUNT4 = 4

Optional properties for dp-controller:
	-interlaced:
		interlace scan mode.
			Progressive if defined, Interlaced if not defined
	-vsync-active-high:
		VSYNC polarity configuration.
			High if defined, Low if not defined
	-hsync-active-high:
		HSYNC polarity configuration.
			High if defined, Low if not defined

Example:

SOC specific portion:
	dp-controller {
		compatible = "samsung,exynos5-dp";
		reg = <0x145b0000 0x10000>;
		interrupts = <10 3>;
		interrupt-parent = <&combiner>;

		dptx-phy {
			reg = <0x10040720>;
			samsung,enable-mask = <1>;
		};

	};

Board Specific portion:
	dp-controller {
		samsung,color-space = <0>;
		samsung,dynamic-range = <0>;
		samsung,ycbcr-coeff = <0>;
		samsung,color-depth = <1>;
		samsung,link-rate = <0x0a>;
		samsung,lane-count = <4>;
	};
