mfd: documentation: dt: Add documentation for the mfd Maxim max77693

    Valid values: 4300000, 4700000, 4800000, 4900000

    Default: 4300000

- led : the LED submodule device node

There are two LED outputs available - FLED1 and FLED2. Each of them can

control a separate LED or they can be connected together to double

the maximum current for a single connected LED. One LED is represented

by one child node.

Required properties:

- compatible : Must be "maxim,max77693-led".

Optional properties:

- maxim,boost-mode :

	In boost mode the device can produce up to 1.2A of total current

	on both outputs. The maximum current on each output is reduced

	to 625mA then. If not enabled explicitly, boost setting defaults to

	LEDS_BOOST_FIXED in case both current sources are used.

	Possible values:

		LEDS_BOOST_OFF (0) - no boost,

		LEDS_BOOST_ADAPTIVE (1) - adaptive mode,

		LEDS_BOOST_FIXED (2) - fixed mode.

- maxim,boost-mvout : Output voltage of the boost module in millivolts.

	Valid values: 3300 - 5500, step by 25 (rounded down)

	Default: 3300

- maxim,mvsys-min : Low input voltage level in millivolts. Flash is not fired

	if chip estimates that system voltage could drop below this level due

	to flash power consumption.

	Valid values: 2400 - 3400, step by 33 (rounded down)

	Default: 2400

Required properties for the LED child node:

- led-sources : see Documentation/devicetree/bindings/leds/common.txt;

		device current output identifiers: 0 - FLED1, 1 - FLED2

- led-max-microamp : see Documentation/devicetree/bindings/leds/common.txt

	Valid values for a LED connected to one FLED output:

		15625 - 250000, step by 15625 (rounded down)

	Valid values for a LED connected to both FLED outputs:

		15625 - 500000, step by 15625 (rounded down)

- flash-max-microamp : see Documentation/devicetree/bindings/leds/common.txt

	Valid values for a single LED connected to one FLED output

	(boost mode must be turned off):

		15625 - 1000000, step by 15625 (rounded down)

	Valid values for a single LED connected to both FLED outputs:

		15625 - 1250000, step by 15625 (rounded down)

	Valid values for two LEDs case:

		15625 - 625000, step by 15625 (rounded down)

- flash-max-timeout-us : see Documentation/devicetree/bindings/leds/common.txt

	Valid values: 62500 - 1000000, step by 62500 (rounded down)

Optional properties for the LED child node:

- label : see Documentation/devicetree/bindings/leds/common.txt

Example:

#include <dt-bindings/leds/common.h>

	max77693@66 {

		compatible = "maxim,max77693";

		reg = <0x66>;

			maxim,thermal-regulation-celsius = <75>;

			maxim,battery-overcurrent-microamp = <3000000>;

			maxim,charge-input-threshold-microvolt = <4300000>;

		led {

			compatible = "maxim,max77693-led";

			maxim,boost-mode = <LEDS_BOOST_FIXED>;

			maxim,boost-mvout = <5000>;

			maxim,mvsys-min = <2400>;

			camera_flash: flash-led {

				label = "max77693-flash";

				led-sources = <0>, <1>;

				led-max-microamp = <500000>;

				flash-max-microamp = <1250000>;

				flash-max-timeout-us = <1000000>;

			};

		};

	};