[media] media: i2c/adp1653: Documentation for devicetree support for adp1653

Documentation for adp1653 bindings.
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

Documentation/devicetree/bindings/media/i2c/adp1653.txt

+* Analog Devices ADP1653 flash LED driver
+
+Required Properties:
+
+  - compatible: Must contain "adi,adp1653"
+
+  - reg: I2C slave address
+
+  - enable-gpios: Specifier of the GPIO connected to EN pin
+
+There are two LED outputs available - flash and indicator. One LED is
+represented by one child node, nodes need to be named "flash" and "indicator".
+
+Required properties of the LED child node:
+- max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+
+Required properties of the flash LED child node:
+
+- flash-max-microamp : see Documentation/devicetree/bindings/leds/common.txt
+- flash-timeout-us : see Documentation/devicetree/bindings/leds/common.txt
+
+Example:
+
+	adp1653: led-controller@30 {
+		compatible = "adi,adp1653";
+		reg = <0x30>;
+		enable-gpios = <&gpio3 24 GPIO_ACTIVE_HIGH>; /* 88 */
+
+		flash {
+			flash-timeout-us = <500000>;
+			flash-max-microamp = <320000>;
+			max-microamp = <50000>;
+		};
+		indicator {
+			max-microamp = <17500>;
+		};
+	};