CS42L42 audio CODEC

Required properties:

  - compatible : "cirrus,cs42l42"

  - reg : the I2C address of the device for I2C.

  - VP-supply, VCP-supply, VD_FILT-supply, VL-supply, VA-supply :
  power supplies for the device, as covered in
  Documentation/devicetree/bindings/regulator/regulator.txt.

Optional properties:

  - reset-gpios : a GPIO spec for the reset pin. If specified, it will be
  deasserted before communication to the codec starts.

  - interrupts : IRQ line info CS42L42.
  (See Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
  for further information relating to interrupt properties)

  - cirrus,ts-inv : Boolean property. Sets the behaviour of the jack plug
  detect switch.

  0 = (Default) Shorted to tip when unplugged, open when plugged.
      This is "inverted tip sense (ITS)" in the datasheet.

  1 = Open when unplugged, shorted to tip when plugged.
      This is "normal tip sense (TS)" in the datasheet.

  - cirrus,ts-dbnc-rise : Debounce the rising edge of TIP_SENSE_PLUG. With no
  debounce, the tip sense pin might be noisy on a plug event.

  0 - 0ms,
  1 - 125ms,
  2 - 250ms,
  3 - 500ms,
  4 - 750ms,
  5 - (Default) 1s,
  6 - 1.25s,
  7 - 1.5s,

  - cirrus,ts-dbnc-fall : Debounce the falling edge of TIP_SENSE_UNPLUG.
  With no debounce, the tip sense pin might be noisy on an unplug event.

  0 - 0ms,
  1 - 125ms,
  2 - 250ms,
  3 - 500ms,
  4 - 750ms,
  5 - (Default) 1s,
  6 - 1.25s,
  7 - 1.5s,

  - cirrus,btn-det-init-dbnce : This sets how long the driver sleeps after
  enabling button detection interrupts. After auto-detection and before
  servicing button interrupts, the HS bias needs time to settle. If you
  don't wait, there is possibility for erroneous button interrupt.

  0ms - 200ms,
  Default = 100ms

  - cirrus,btn-det-event-dbnce : This sets how long the driver delays after
  receiving a button press interrupt. With level detect interrupts, you want
  to wait a small amount of time to make sure the button press is making a
  clean connection with the bias resistors.

  0ms - 20ms,
  Default = 10ms

  - cirrus,bias-lvls : For a level-detect headset button scheme, each button
  will bias the mic pin to a certain voltage. To determine which button was
  pressed, the driver will compare this biased voltage to sequential,
  decreasing voltages and will stop when a comparator is tripped,
  indicating a comparator voltage < bias voltage. This value represents a
  percentage of the internally generated HS bias voltage. For different
  hardware setups, a designer might want to tweak this. This is an array of
  descending values for the comparator voltage.

  Array of 4 values
  Each 0-63
  < x1 x2 x3 x4 >
  Default = < 15 8 4 1>

  - cirrus,hs-bias-sense-disable: This is boolean property. If present the
  HSBIAS sense is disabled. Configures HSBIAS output current sense through
  the external 2.21-k resistor. HSBIAS_SENSE is hardware feature to reduce
  the potential pop noise during the headset plug out slowly. But on some
  platforms ESD voltage will affect it causing test to fail, especially
  with CTIA headset type. For different hardware setups, a designer might
  want to tweak default behavior.

Example:

cs42l42: cs42l42@48 {
	compatible = "cirrus,cs42l42";
	reg = <0x48>;
	VA-supply = <&dummy_vreg>;
	VP-supply = <&dummy_vreg>;
	VCP-supply = <&dummy_vreg>;
	VD_FILT-supply = <&dummy_vreg>;
	VL-supply = <&dummy_vreg>;

	reset-gpios = <&axi_gpio_0 1 0>;
	interrupt-parent = <&gpio0>;
	interrupts = <55 8>

	cirrus,ts-inv = <0x00>;
	cirrus,ts-dbnc-rise = <0x05>;
	cirrus,ts-dbnc-fall = <0x00>;
	cirrus,btn-det-init-dbnce = <100>;
	cirrus,btn-det-event-dbnce = <10>;
	cirrus,bias-lvls = <0x0F 0x08 0x04 0x01>;
	cirrus,hs-bias-ramp-rate = <0x02>;
};