ASoC: cs35l34: Add device tree bindings file for cs35l34

Add device tree bindings file for the cs35l34 8V boosted
class D amplifier.
Signed-off-by: Paul Handrigan <Paul.Handrigan@cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/cs35l34.txt

+CS35L34 Speaker Amplifier
+
+Required properties:
+
+  - compatible : "cirrus,cs35l34"
+
+  - reg : the I2C address of the device for I2C.
+
+  - VA-supply, VP-supply : power supplies for the device,
+    as covered in
+    Documentation/devicetree/bindings/regulator/regulator.txt.
+
+  - cirrus,boost-vtge-millivolt : Boost Voltage Value.  Configures the boost
+    converter's output voltage in mV. The range is from VP to 8V with
+    increments of 100mV.
+
+  - cirrus,boost-nanohenry: Inductor value for boost converter. The value is
+    in nH and they can be values of 1000nH, 1100nH, 1200nH, 1500nH, and 2200nH.
+
+Optional properties:
+
+  - reset-gpios: GPIO used to reset the amplifier.
+
+  - interrupt-parent : Specifies the phandle of the interrupt controller to
+    which the IRQs from CS35L34 are delivered to.
+  - interrupts : IRQ line info CS35L34.
+    (See Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+    for further information relating to interrupt properties)
+
+  - cirrus,boost-peak-milliamp : Boost converter peak current limit in mA. The
+    range starts at 1200mA and goes to a maximum of 3840mA with increments of
+    80mA. The default value is 2480mA.
+
+  - cirrus,i2s-sdinloc : ADSP SDIN I2S channel location. Indicates whether the
+    received mono data is in the left or right portion of the I2S frame
+    according to the AD0 pin or directly via this configuration.
+    0x0 (Default) = Selected by AD0 input (if AD0 = LOW, use left channel),
+    0x2 = Left,
+    0x1 = Selected by the inversion of the AD0 input (if AD0 = LOW, use right
+    channel),
+    0x3 = Right.
+
+  - cirrus,gain-zc-disable: Boolean property. If set, the gain change will take
+    effect without waiting for a zero cross.
+
+  - cirrus,tdm-rising-edge: Boolean property. If set, data is on the rising edge of
+    SCLK. Otherwise, data is on the falling edge of SCLK.
+
+
+Example:
+
+cs35l34: cs35l34@40 {
+	compatible = "cirrus,cs35l34";
+	reg = <0x40>;
+
+	interrupt-parent = <&gpio8>;
+	interrupts = <3 IRQ_TYPE_LEVEL_LOW>;
+
+	reset-gpios = <&gpio 10 0>;
+
+	cirrus,boost-vtge-milltvolt = <8000>; /* 8V */
+	cirrus,boost-ind-nanohenry = <1000>; /* 1uH */
+	cirrus,boost-peak-milliamp = <3000>; /* 3A */
+};