* Omnivision OV7670 CMOS sensor

The Omnivision OV7670 sensor supports multiple resolutions output, such as
CIF, SVGA, UXGA. It also can support the YUV422/420, RGB565/555 or raw RGB
output formats.

Required Properties:
- compatible: should be "ovti,ov7670"
- clocks: reference to the xclk input clock.
- clock-names: should be "xclk".

Optional Properties:
- reset-gpios: reference to the GPIO connected to the resetb pin, if any.
  Active is low.
- powerdown-gpios: reference to the GPIO connected to the pwdn pin, if any.
  Active is high.

The device node must contain one 'port' child node for its digital output
video port, in accordance with the video interface bindings defined in
Documentation/devicetree/bindings/media/video-interfaces.txt.

Example:

	i2c1: i2c@f0018000 {
		ov7670: camera@21 {
			compatible = "ovti,ov7670";
			reg = <0x21>;
			pinctrl-names = "default";
			pinctrl-0 = <&pinctrl_pck0_as_isi_mck &pinctrl_sensor_power &pinctrl_sensor_reset>;
			reset-gpios = <&pioE 11 GPIO_ACTIVE_LOW>;
			powerdown-gpios = <&pioE 13 GPIO_ACTIVE_HIGH>;
			clocks = <&pck0>;
			clock-names = "xclk";
			assigned-clocks = <&pck0>;
			assigned-clock-rates = <25000000>;

			port {
				ov7670_0: endpoint {
					remote-endpoint = <&isi_0>;
				};
			};
		};
	};