mfd: da9062: dt: Add bindings for DA9062 driver

Add device Tree Bindings for the DA9062 driver
Signed-off-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Documentation/devicetree/bindings/mfd/da9062.txt

+* Dialog DA9062 Power Management Integrated Circuit (PMIC)
+
+DA9062 consists of a large and varied group of sub-devices:
+
+Device                   Supply Names    Description
+------                   ------------    -----------
+da9062-regulator        :               : LDOs & BUCKs
+da9062-watchdog         :               : Watchdog Timer
+
+======
+
+Required properties:
+
+- compatible : Should be "dlg,da9062".
+- reg : Specifies the I2C slave address (this defaults to 0x58 but it can be
+  modified to match the chip's OTP settings).
+- interrupt-parent : Specifies the reference to the interrupt controller for
+  the DA9062.
+- interrupts : IRQ line information.
+- interrupt-controller
+
+See Documentation/devicetree/bindings/interrupt-controller/interrupts.txt for
+further information on IRQ bindings.
+
+Sub-nodes:
+
+- regulators : This node defines the settings for the LDOs and BUCKs. The
+  DA9062 regulators are bound using their names listed below:
+
+    buck1    : BUCK_1
+    buck2    : BUCK_2
+    buck3    : BUCK_3
+    buck4    : BUCK_4
+    ldo1     : LDO_1
+    ldo2     : LDO_2
+    ldo3     : LDO_3
+    ldo4     : LDO_4
+
+  The component follows the standard regulator framework and the bindings
+  details of individual regulator device can be found in:
+  Documentation/devicetree/bindings/regulator/regulator.txt
+
+
+- watchdog: This node defines the settings for the watchdog driver associated
+  with the DA9062 PMIC. The compatible = "dlg,da9062-watchdog" should be added
+  if a node is created.
+
+
+Example:
+
+	pmic0: da9062@58 {
+		compatible = "dlg,da9062";
+		reg = <0x58>;
+		interrupt-parent = <&gpio6>;
+		interrupts = <11 IRQ_TYPE_LEVEL_LOW>;
+		interrupt-controller;
+
+		watchdog {
+			compatible = "dlg,da9062-watchdog";
+		};
+
+		regulators {
+			DA9062_BUCK1: buck1 {
+				regulator-name = "BUCK1";
+				regulator-min-microvolt = <300000>;
+				regulator-max-microvolt = <1570000>;
+				regulator-min-microamp = <500000>;
+				regulator-max-microamp = <2000000>;
+				regulator-boot-on;
+			};
+			DA9062_LDO1: ldo1 {
+				regulator-name = "LDO_1";
+				regulator-min-microvolt = <900000>;
+				regulator-max-microvolt = <3600000>;
+				regulator-boot-on;
+			};
+		};
+	};
+