Cirrus Logic Arizona class audio SoCs

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

This document lists Extcon specific bindings, see the primary binding document:
  ../mfd/arizona.txt

Optional properties:

  - wlf,hpdet-channel : Headphone detection channel.
    ARIZONA_ACCDET_MODE_HPL or 1 - Headphone detect mode is set to HPDETL
    ARIZONA_ACCDET_MODE_HPR or 2 - Headphone detect mode is set to HPDETR
    If this node is not mentioned or if the value is unknown, then
    headphone detection mode is set to HPDETL.

  - wlf,use-jd2 : Use the additional JD input along with JD1 for dual pin jack
    detection.
  - wlf,use-jd2-nopull : Internal pull on JD2 is disabled when used for
    jack detection.
  - wlf,jd-invert : Invert the polarity of the jack detection switch

  - wlf,micd-software-compare : Use a software comparison to determine mic
    presence
  - wlf,micd-detect-debounce : Additional software microphone detection
    debounce specified in milliseconds.
  - wlf,micd-pol-gpio : GPIO specifier for the GPIO controlling the headset
    polarity if one exists.
  - wlf,micd-bias-start-time : Time allowed for MICBIAS to startup prior to
    performing microphone detection, specified as per the ARIZONA_MICD_TIME_XXX
    defines.
  - wlf,micd-rate : Delay between successive microphone detection measurements,
    specified as per the ARIZONA_MICD_TIME_XXX defines.
  - wlf,micd-dbtime : Microphone detection hardware debounces specified as the
    number of measurements to take, valid values being 2 and 4.
  - wlf,micd-timeout-ms : Timeout for microphone detection, specified in
    milliseconds.
  - wlf,micd-force-micbias : Force MICBIAS continuously on during microphone
    detection.
  - wlf,micd-configs : Headset polarity configurations (generally used for
    detection of CTIA / OMTP headsets), the field can be of variable length
    but should always be a multiple of 3 cells long, each three cell group
    represents one polarity configuration.
    The first cell defines the accessory detection pin, zero will use MICDET1
    and all other values will use MICDET2.
    The second cell represents the MICBIAS to be used.
    The third cell represents the value of the micd-pol-gpio pin.

  - wlf,gpsw : Settings for the general purpose switch

Example:

codec: wm8280@0 {
	compatible = "wlf,wm8280";
	reg = <0>;
	...

	wlf,use-jd2;
	wlf,use-jd2-nopull;
	wlf,jd-invert;

	wlf,micd-software-compare;
	wlf,micd-detect-debounce = <0>;
	wlf,micd-pol-gpio = <&codec 2 0>;
	wlf,micd-rate = <ARIZONA_MICD_TIME_8MS>;
	wlf,micd-dbtime = <4>;
	wlf,micd-timeout-ms = <100>;
	wlf,micd-force-micbias;
	wlf,micd-configs = <
		0 1 0 /* MICDET1 MICBIAS1 GPIO=low */
		1 2 1 /* MICDET2 MICBIAS2 GPIO=high */
	>;

	wlf,gpsw = <0>;
};