Wolfson Arizona class audio SoCs

These devices are audio SoCs with extensive digital capabilites and a range
of analogue I/O.

Required properties:

  - compatible : One of the following chip-specific strings:
        "wlf,wm5102"
        "wlf,wm5110"
        "wlf,wm8997"
  - reg : I2C slave address when connected using I2C, chip select number when
    using SPI.

  - interrupts : The interrupt line the /IRQ signal for the device is
    connected to.
  - interrupt-controller : Arizona class devices contain interrupt controllers
    and may provide interrupt services to other devices.
  - interrupt-parent : The parent interrupt controller.
  - #interrupt-cells: the number of cells to describe an IRQ, this should be 2.
    The first cell is the IRQ number.
    The second cell is the flags, encoded as the trigger masks from
    Documentation/devicetree/bindings/interrupts.txt

  - gpio-controller : Indicates this device is a GPIO controller.
  - #gpio-cells : Must be 2. The first cell is the pin number and the
    second cell is used to specify optional parameters (currently unused).

  - AVDD-supply, DBVDD1-supply, DBVDD2-supply, DBVDD3-supply (wm5102, wm5110),
    CPVDD-supply, SPKVDDL-supply (wm5102, wm5110), SPKVDDR-supply (wm5102,
    wm5110), SPKVDD-supply (wm8997) : Power supplies for the device, as covered
    in Documentation/devicetree/bindings/regulator/regulator.txt

Optional properties:

  - wlf,reset : GPIO specifier for the GPIO controlling /RESET
  - wlf,ldoena : GPIO specifier for the GPIO controlling LDOENA

  - wlf,gpio-defaults : A list of GPIO configuration register values. If
    absent, no configuration of these registers is performed. If any
    entry has a value that is out of range for a 16 bit register then
    the chip default will be used.  If present exactly five values must
    be specified.

  - wlf,inmode : A list of INn_MODE register values, where n is the number
    of input signals. Valid values are 0 (Differential), 1 (Single-ended) and
    2 (Digital Microphone). If absent, INn_MODE registers set to 0 by default.
    If present, values must be specified less than or equal to the number of
    input singals. If values less than the number of input signals, elements
    that has not been specifed are set to 0 by default.

  - DCVDD-supply, MICVDD-supply : Power supplies, only need to be specified if
    they are being externally supplied. As covered in
    Documentation/devicetree/bindings/regulator/regulator.txt

Optional subnodes:
  - ldo1 : Initial data for the LDO1 regulator, as covered in
    Documentation/devicetree/bindings/regulator/regulator.txt
  - micvdd : Initial data for the MICVDD regulator, as covered in
    Documentation/devicetree/bindings/regulator/regulator.txt

Example:

codec: wm5102@1a {
	compatible = "wlf,wm5102";
	reg = <0x1a>;
	interrupts = <347>;
	interrupt-controller;
	#interrupt-cells = <2>;
        interrupt-parent = <&gic>;

	gpio-controller;
	#gpio-cells = <2>;

	wlf,gpio-defaults = <
		0x00000000 /* AIF1TXLRCLK */
		0xffffffff
		0xffffffff
		0xffffffff
		0xffffffff
	>;
};