[media] atmel-isi: update device tree bindings documentation

Atmel Image Sensor Interface (ISI) SoC Camera Subsystem

----------------------------------------------

Required properties:

- compatible: must be "atmel,at91sam9g45-isi"

- reg: physical base address and length of the registers set for the device;

- interrupts: should contain IRQ line for the ISI;

- clocks: list of clock specifiers, corresponding to entries in

          the clock-names property;

- clock-names: must contain "isi_clk", which is the isi peripherial clock.

ISI supports a single port node with parallel bus. It should contain one

Atmel Image Sensor Interface (ISI)

----------------------------------

Required properties for ISI:

- compatible: must be "atmel,at91sam9g45-isi".

- reg: physical base address and length of the registers set for the device.

- interrupts: should contain IRQ line for the ISI.

- clocks: list of clock specifiers, corresponding to entries in the clock-names

	property; please refer to clock-bindings.txt.

- clock-names: required elements: "isi_clk".

- pinctrl-names, pinctrl-0: please refer to pinctrl-bindings.txt.

ISI supports a single port node with parallel bus. It shall contain one

'port' child node with child 'endpoint' node. Please refer to the bindings

defined in Documentation/devicetree/bindings/media/video-interfaces.txt.

Endpoint node properties

------------------------

- bus-width: <8> or <10> (mandatory)

- hsync-active (default: active high)

- vsync-active (default: active high)

- pclk-sample (default: sample on falling edge)

- remote-endpoint: A phandle to the bus receiver's endpoint node (mandatory).

Example:

isi: isi@f0034000 {

	compatible = "atmel,at91sam9g45-isi";

	reg = <0xf0034000 0x4000>;

	interrupts = <37 IRQ_TYPE_LEVEL_HIGH 5>;

	pinctrl-names = "default";

	pinctrl-0 = <&pinctrl_isi_data_0_7>;

	clocks = <&isi_clk>;

	clock-names = "isi_clk";

		pinctrl-names = "default";

		pinctrl-0 = <&pinctrl_isi>;

	port {

			#address-cells = <1>;

			#size-cells = <0>;

		isi_0: endpoint {

			remote-endpoint = <&ov2640_0>;

			bus-width = <8>;

			vsync-active = <1>;

			hsync-active = <1>;

		};

	};

};

i2c1: i2c@f0018000 {

		ov2640: camera@0x30 {

	ov2640: camera@30 {

		compatible = "ovti,ov2640";

		reg = <0x30>;

		pinctrl-names = "default";

		pinctrl-0 = <&pinctrl_pck0_as_isi_mck &pinctrl_sensor_power &pinctrl_sensor_reset>;

		resetb-gpios = <&pioE 11 GPIO_ACTIVE_LOW>;

		pwdn-gpios = <&pioE 13 GPIO_ACTIVE_HIGH>;

		clocks = <&pck0>;

		clock-names = "xvclk";

		assigned-clocks = <&pck0>;

		assigned-clock-rates = <25000000>;

		port {

			ov2640_0: endpoint {