AS3711 is an I2C PMIC from Austria MicroSystems with multiple DCDC and LDO power
supplies, a battery charger and an RTC. So far only bindings for the two stepup
DCDC converters are defined. Other DCDC and LDO supplies are configured, using
standard regulator properties, they must belong to a sub-node, called
"regulators" and be called "sd1" to "sd4" and "ldo1" to "ldo8." Stepup converter
configuration should be placed in a subnode, called "backlight."

Compulsory properties:
- compatible		: must be "ams,as3711"
- reg			: specifies the I2C address

To use the SU1 converter as a backlight source the following two properties must
be provided:
- su1-dev		: framebuffer phandle
- su1-max-uA		: maximum current

To use the SU2 converter as a backlight source the following two properties must
be provided:
- su2-dev		: framebuffer phandle
- su1-max-uA		: maximum current

Additionally one of these properties must be provided to select the type of
feedback used:
- su2-feedback-voltage	: voltage feedback is used
- su2-feedback-curr1	: CURR1 input used for current feedback
- su2-feedback-curr2	: CURR2 input used for current feedback
- su2-feedback-curr3	: CURR3 input used for current feedback
- su2-feedback-curr-auto: automatic current feedback selection

and one of these to select the over-voltage protection pin
- su2-fbprot-lx-sd4	: LX_SD4 is used for over-voltage protection
- su2-fbprot-gpio2	: GPIO2 is used for over-voltage protection
- su2-fbprot-gpio3	: GPIO3 is used for over-voltage protection
- su2-fbprot-gpio4	: GPIO4 is used for over-voltage protection

If "su2-feedback-curr-auto" is selected, one or more of the following properties
have to be specified:
- su2-auto-curr1	: use CURR1 input for current feedback
- su2-auto-curr2	: use CURR2 input for current feedback
- su2-auto-curr3	: use CURR3 input for current feedback

Example:

as3711@40 {
	compatible = "ams,as3711";
	reg = <0x40>;

	regulators {
		sd4 {
			regulator-name = "1.215V";
			regulator-min-microvolt = <1215000>;
			regulator-max-microvolt = <1235000>;
		};
		ldo2 {
			regulator-name = "2.8V CPU";
			regulator-min-microvolt = <2800000>;
			regulator-max-microvolt = <2800000>;
			regulator-always-on;
			regulator-boot-on;
		};
	};

	backlight {
		compatible = "ams,as3711-bl";
		su2-dev = <&lcdc>;
		su2-max-uA = <36000>;
		su2-feedback-curr-auto;
		su2-fbprot-gpio4;
		su2-auto-curr1;
		su2-auto-curr2;
		su2-auto-curr3;
	};
};
