dt-bindings: regulator: add PMIC PM8008 regulator bindings

Add PMIC PM8008 regulator device bindings.  PM8008 chips contain
7 LDO regulators along with a top-level chip sleep feature.

Change-Id: If36c21dbf382b2bc460e712b0098f67d569004ca

bindings/regulator/qcom,pm8008-regulator.txt

@@ -0,0 +1,124 @@
+Qualcomm Technologies, Inc. PM8008 Regulator
+
+PM8008 is an I2C based PMIC regulator chip.
+
+=======================
+Required Node Structure
+=======================
+
+==============================================
+PM8008 chip specific device
+==============================================
+PM8008 chip specific properties:
+
+- compatible:
+  Usage: required
+  Value type: <string>
+  Definition: must be "qcom,pm8008-chip"
+
+- pinctrl-names:
+  Usage: required
+  Value type: <string>
+  Definition: must be "default"
+
+- pinctrl-0:
+  Usage: required
+  Value type: <phandle>
+  Definition: pinctrol handle for chip enable GPIO.
+
+- regulator sub-node:
+  Usage: required
+  Value type: <child sub node>
+  Definition: Chip enable regulator device to control chip enable
+		functionality. Must be "qcom,pm8008-chip-en".
+Example:
+	qcom,pm8008-chip@900 {
+		compatible = "qcom,pm8008-chip";
+		pinctrl-names = "default";
+		pinctrl-0 = <&pincontrol handle>; // chip enable GPIO
+
+		PM8008_EN: qcom,pm8008-chip-en {
+			regulator-name = "pm8008-chip-en";
+		};
+	};
+
+
+========================================================
+PM8008 regulator device
+========================================================
+PM8008 chip regulator specific properties:
+
+- compatible:
+  Usage: required
+  Value type: <string>
+  Definition: must be "qcom,pm8008-regulator"
+
+- <pin>-supply:
+  Usage: optional
+  Value type: <phandle>
+  Definition: Reference to parent regulator supplying the input pin, as
+		described in the data sheet.
+		Must be one of the following:
+		vdd_l1_l2-supply: supply for LDO1/LDO2 of PM8008
+		vdd_l3_l4-supply: supply for LDO3/LDO4 of PM8008
+		vdd_l5-supply: supply for LDO5 of PM8008
+		vdd_l6-supply: supply for LDO6 of PM8008
+		vdd_l7-supply: supply for LDO7 of PM8008
+
+- pm8008_en-supply:
+  Usage: required
+  Value type: <phandle>
+  Definition: Reference to PM8008 chip enable regulator, which manages
+		chip enable functionlity of PM8008.
+
+============================================================================
+Second Level Nodes - PM8008 regulator peripherals of PM8008 regulator device
+============================================================================
+
+- qcom,hpm-min-load:
+  Usage: optional
+  Value type: <u32>
+  Definition: Load current in uA which corresponds to the minimum load
+		which requires the regulator to be in high power mode.
+
+- qcom,min-dropout-voltage:
+  Usage: optional
+  Value type: <u32>
+  Definition: Specifies the minimum voltage in microvolts that the parent
+		supply regulator must output above the output of this
+		regulator.  It is only meaningful if the corresponding parent
+		supply property has been specified in the first level node.
+
+- qcom,init-voltage
+  Usage:      optional
+  Value type: <u32>
+  Definition: Specifies the initial voltage in microvolts to for a regulator.
+
+- qcom,strong-pd
+  Usage:      optional
+  Value type: <bool>
+  Definition: Property if present enables strong pull-down.
+
+The content of each sub-node is defined by the standard binding for regulators -
+see regulator.txt - with additional custom properties described below:
+
+Example:
+
+	qcom,pm8008-regulator {
+		compatible = "qcom,pm8008-regulator";
+
+		pm8008_en-supply = <&PM8008_EN>;
+		vdd_l1_l2-supply = <&parent-supply>;
+		...
+
+		L1: qcom,pm8008-l1@4000 {
+			reg = /bits/ 16 <0x4000>;
+			regulator-name = "pm8008_l1";
+			regulator-min-microvolt = <2900000>;
+			regulator-max-microvolt = <3100000>;
+			qcom,min-dropout-voltage = <100000>;
+			qcom,hpm-min-load = <10000>;
+		}
+
+		.....
+	};