[media] Documentation: dt: Add binding documentation for S5C73M3 camera

Samsung S5C73M3 8Mp camera ISP

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

The S5C73M3 camera ISP supports MIPI CSI-2 and parallel (ITU-R BT.656) video

data busses. The I2C bus is the main control bus and additionally the SPI bus

is used, mostly for transferring the firmware to and from the device. Two

slave device nodes corresponding to these control bus interfaces are required

and should be placed under respective bus controller nodes.

I2C slave device node

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

Required properties:

- compatible	    : "samsung,s5c73m3";

- reg		    : I2C slave address of the sensor;

- vdd-int-supply    : digital power supply (1.2V);

- vdda-supply	    : analog power supply (1.2V);

- vdd-reg-supply    : regulator input power supply (2.8V);

- vddio-host-supply : host I/O power supply (1.8V to 2.8V);

- vddio-cis-supply  : CIS I/O power supply (1.2V to 1.8V);

- vdd-af-supply     : lens power supply (2.8V);

- xshutdown-gpios   : specifier of GPIO connected to the XSHUTDOWN pin;

- standby-gpios     : specifier of GPIO connected to the STANDBY pin;

- clocks	    : should contain list of phandle and clock specifier pairs

		      according to common clock bindings for the clocks described

		      in the clock-names property;

- clock-names	    : should contain "cis_extclk" entry for the CIS_EXTCLK clock;

Optional properties:

- clock-frequency   : the frequency at which the "cis_extclk" clock should be

		      configured to operate, in Hz; if this property is not

		      specified default 24 MHz value will be used.

The common video interfaces bindings (see video-interfaces.txt) should be used

to specify link from the S5C73M3 to an external image data receiver. The S5C73M3

device node should contain one 'port' child node with an 'endpoint' subnode for

this purpose. The data link from a raw image sensor to the S5C73M3 can be

similarly specified, but it is optional since the S5C73M3 ISP and a raw image

sensor are usually inseparable and form a hybrid module.

Following properties are valid for the endpoint node(s):

endpoint subnode

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

- data-lanes : (optional) specifies MIPI CSI-2 data lanes as covered in

  video-interfaces.txt. This sensor doesn't support data lane remapping

  and physical lane indexes in subsequent elements of the array should

  be only consecutive ascending values.

SPI device node

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

Required properties:

- compatible	    : "samsung,s5c73m3";

For more details see description of the SPI busses bindings

(../spi/spi-bus.txt) and bindings of a specific bus controller.

Example:

i2c@138A000000 {

	...

	s5c73m3@3c {

		compatible = "samsung,s5c73m3";

		reg = <0x3c>;

		vdd-int-supply = <&buck9_reg>;

		vdda-supply = <&ldo17_reg>;

		vdd-reg-supply = <&cam_io_reg>;

		vddio-host-supply = <&ldo18_reg>;

		vddio-cis-supply = <&ldo9_reg>;

		vdd-af-supply = <&cam_af_reg>;

		clock-frequency = <24000000>;

		clocks = <&clk 0>;

		clock-names = "cis_extclk";

		reset-gpios = <&gpf1 3 1>;

		standby-gpios = <&gpm0 1 1>;

		port {

			s5c73m3_ep: endpoint {

				remote-endpoint = <&csis0_ep>;

				data-lanes = <1 2 3 4>;

			};

		};

	};

};

spi@1392000 {

	...

	s5c73m3_spi: s5c73m3@0 {

		compatible = "samsung,s5c73m3";

		reg = <0>;

		...

	};

};