Maxim MAX17135 Voltage Regulator

The MAX17135 is a complete power-management IC for E-paper displays that
provides source- and gate-driver power supplies, a high-speed VCOM amplifier,
and a temperature sensor. It is interfaced to the host controller using an
i2c interface.

Required properties :
- compatible : "maxim,max17135"
- reg: Specifies the i2c slave address of the pmic block.
- vneg_pwrup: the timing for VNEG power up
- gvee_pwrup: the timing for GVEE power up
- vpos_pwrup: the timing for VPOS power up
- gvdd_pwrup: the timing for GVDD power up
- gvdd_pwrdn: the timing for GVDD power down
- vpos_pwrdn: the timing for VPOS power down
- gvee_pwrdn: the timing for GVEE power down
- vneg_pwrdn: the timing for VNEG power down
- gpio_pmic_pwrgood: gpio setting for EPDC_PWRSTAT
- gpio_pmic_vcom_ctrl: gpio setting for EPDC_VCOM
- gpio_pmic_wakeup: gpio setting for EPDC_PWRWAKEUP
- gpio_pmic_v3p3: gpio setting for EPDC_PWRCTRL0
- gpio_pmic_intr: gpio setting for EPDC_PWRINT

Optional properties :
- SENSOR-supply: the gpio regulator to control the supply for this chip


Regulators: The regulators of max17135 that have to be instantiated should be
included in a sub-node named 'regulators'. Regulator nodes included in this
sub-node should be of the format as listed below.

        regulator_name {
                standard regulator bindings here
        };

Example:
	max17135@48 {
		compatible = "maxim,max17135";
		reg = <0x48>;
		vneg_pwrup = <1>;
		gvee_pwrup = <1>;
		vpos_pwrup = <2>;
		gvdd_pwrup = <1>;
		gvdd_pwrdn = <1>;
		vpos_pwrdn = <2>;
		gvee_pwrdn = <1>;
		vneg_pwrdn = <1>;
		SENSOR-supply = <&reg_sensor>;
		gpio_pmic_pwrgood = <&gpio2 21 0>;
		gpio_pmic_vcom_ctrl = <&gpio3 17 0>;
		gpio_pmic_wakeup = <&gpio3 20 0>;
		gpio_pmic_v3p3 = <&gpio2 20 0>;
		gpio_pmic_intr = <&gpio2 25 0>;

		regulators {
			DISPLAY_reg: DISPLAY {
				regulator-name = "DISPLAY";
			};

			GVDD_reg: GVDD {
				regulator-name = "GVDD";
				regulator-min-microvolt = <20000000>;
				regulator-max-microvolt = <20000000>;
			};

			GVEE_reg: GVEE {
				regulator-name = "GVEE";
				/* 2's-compliment, -22000000 */
				regulator-min-microvolt = <0xfeb04e80>;
				regulator-max-microvolt = <0xfeb04e80>;
			};

			HVINN_reg: HVINN {
				regulator-name = "HVINN";
				/* 2's-compliment, -22000000 */
				regulator-min-microvolt = <0xfeb04e80>;
				regulator-max-microvolt = <0xfeb04e80>;
			};

			HVINP_reg: HVINP {
				regulator-name = "HVINP";
				regulator-min-microvolt = <20000000>;
				regulator-max-microvolt = <20000000>;
			};

			VCOM_reg: VCOM {
				regulator-name = "VCOM";
				/* 2's-compliment, -4325000 */
				regulator-min-microvolt = <0xffbe0178>;
				/* 2's-compliment, -500000 */
				regulator-max-microvolt = <0xfff85ee0>;
			};

			VNEG_reg: VNEG {
				regulator-name = "VNEG";
				/* 2's-compliment, -15000000 */
				regulator-min-microvolt = <0xff1b1e40>;
				regulator-max-microvolt = <0xff1b1e40>;
			};

			VPOS_reg: VPOS {
				regulator-name = "VPOS";
				regulator-min-microvolt = <15000000>;
				regulator-max-microvolt = <15000000>;
			};

			V3P3_reg: V3P3 {
				regulator-name = "V3P3";
			};
		};
	};