Binding for TI/National Semiconductor LP872x Driver

Required properties:
  - compatible: "ti,lp8720" or "ti,lp8725"
  - reg: I2C slave address. 0x7d = LP8720, 0x7a = LP8725

Optional properties:
  - ti,general-config: the value of LP872X_GENERAL_CFG register (u8)
    (LP8720)
    bit[2]: BUCK output voltage control by external DVS pin or register
            1 = external pin, 0 = bit7 of register 08h
    bit[1]: sleep control by external DVS pin or register
            1 = external pin, 0 = bit6 of register 08h
    bit[0]: time step unit(usec). 1 = 25, 0 = 50

    (LP8725)
    bit[7:6]: time step unit(usec). 00 = 32, 01 = 64, 10 = 128, 11 = 256
    bit[4]:   BUCK2 enable control. 1 = enable, 0 = disable
    bit[3]:   BUCK2 output voltage register address. 1 = 0Ah, 0 = 0Bh
    bit[2]:   BUCK1 output voltage control by external DVS pin or register
              1 = register 08h, 0 = DVS
    bit[1]:   LDO sleep control. 1 = sleep mode, 0 = normal
    bit[0]:   BUCK1 enable control, 1 = enable, 0 = disable

    For more details, please see the datasheet.

  - ti,update-config: define it when LP872X_GENERAL_CFG register should be set
  - ti,dvs-gpio: GPIO specifier for external DVS pin control of LP872x devices.
  - ti,dvs-vsel: DVS selector. 0 = SEL_V1, 1 = SEL_V2.
  - ti,dvs-state: initial DVS pin state. 0 = DVS_LOW, 1 = DVS_HIGH.
  - enable-gpios: GPIO specifier for EN pin control of LP872x devices.

  Sub nodes for regulator_init_data
    LP8720 has maximum 6 nodes. (child name: ldo1 ~ 5 and buck)
    LP8725 has maximum 9 nodes. (child name: ldo1 ~ 5, lilo1,2 and buck1,2)
    For more details, please see the following binding document.
    (Documentation/devicetree/bindings/regulator/regulator.txt)

Datasheet
  - LP8720: https://www.ti.com/lit/ds/symlink/lp8720.pdf
  - LP8725: https://www.ti.com/lit/ds/symlink/lp8725.pdf

Example 1) LP8720

lp8720@7d {
	compatible = "ti,lp8720";
	reg = <0x7d>;

	/* external DVS pin used, timestep is 25usec */
	ti,general-config = /bits/ 8 <0x03>;
	ti,update-config;

	/*
	 * The dvs-gpio depends on the processor environment.
	 * For example, following GPIO specifier means GPIO134 in OMAP4.
	 */
	ti,dvs-gpio = <&gpio5 6 0>;
	ti,dvs-vsel = /bits/ 8 <1>;		/* SEL_V2 */
	ti,dvs-state = /bits/ 8 <1>;		/* DVS_HIGH */

	vaf: ldo1 {
		regulator-min-microvolt = <1200000>;
		regulator-max-microvolt = <3300000>;
	};

	vmmc: ldo2 {
		regulator-min-microvolt = <1200000>;
		regulator-max-microvolt = <3300000>;
	};

	vcam_io: ldo3 {
		regulator-min-microvolt = <1200000>;
		regulator-max-microvolt = <3300000>;
		regulator-boot-on;
	};

	vcam_core: ldo4 {
		regulator-min-microvolt = <800000>;
		regulator-max-microvolt = <2850000>;
		regulator-boot-on;
	};

	vcam: ldo5 {
		regulator-min-microvolt = <1200000>;
		regulator-max-microvolt = <3300000>;
	};

	vcc: buck {
		regulator-name = "VBUCK";
		regulator-min-microvolt = <800000>;
		regulator-max-microvolt = <2300000>;
	};
};

Example 2) LP8725

lp8725@7a {
	compatible = "ti,lp8725";
	reg = <0x7a>;

	/* Enable BUCK1,2, no DVS, normal LDO mode, timestep is 256usec */
	ti,general-config = /bits/ 8 <0xdd>;
	ti,update-config;

	vcam_io: ldo1 {
		regulator-min-microvolt = <1200000>;
		regulator-max-microvolt = <3300000>;
	};

	vcam_core: ldo2 {
		regulator-min-microvolt = <1200000>;
		regulator-max-microvolt = <3300000>;
	};

	vcam: ldo3 {
		regulator-min-microvolt = <1200000>;
		regulator-max-microvolt = <3300000>;
	};

	vcmmb_io: ldo4 {
		regulator-min-microvolt = <1200000>;
		regulator-max-microvolt = <3300000>;
		regulator-boot-on;
	};

	vcmmb_core: ldo5 {
		regulator-min-microvolt = <1200000>;
		regulator-max-microvolt = <3300000>;
		regulator-boot-on;
	};

	vaux1: lilo1 {
		regulator-name = "VAUX1";
		regulator-min-microvolt = <800000>;
		regulator-max-microvolt = <3300000>;
	};

	vaux2: lilo2 {
		regulator-name = "VAUX2";
		regulator-min-microvolt = <800000>;
		regulator-max-microvolt = <3300000>;
	};

	vcc1: buck1 {
		regulator-name = "VBUCK1";
		regulator-min-microvolt = <800000>;
		regulator-max-microvolt = <3000000>;
		regulator-min-microamp  = <460000>;
		regulator-max-microamp  = <1370000>;
		regulator-boot-on;
	};

	vcc2: buck2 {
		regulator-name = "VBUCK2";
		regulator-min-microvolt = <800000>;
		regulator-max-microvolt = <3000000>;
		regulator-min-microamp  = <460000>;
		regulator-max-microamp  = <1370000>;
		regulator-boot-on;
	};
};