Qualcomm Technologies, Inc. WCD GPIO block

This binding describes the GPIO block found in the WCD934X series of
audio codec's from QTI.

- compatible:
	Usage: required
	Value type: <string>
	Definition: must be "qcom,wcd-pinctrl"

- qcom,num-gpios:
	Usage: required
	Value type: <u32>
	Definition: Number of GPIO's supported by the controller

- gpio-controller:
	Usage: required
	Value type: <none>
	Definition: Mark the device node as a GPIO controller

- #gpio-cells:
	Usage: required
	Value type: <u32>
	Definition: Must be 2;
		    the first cell will be used to define gpio number and the
		    second denotes the flags for this gpio

Please refer to ../gpio/gpio.txt for a general description of GPIO bindings.

Please refer to pinctrl-bindings.txt in this directory for details of the
common pinctrl bindings used by client devices, including the meaning of the
phrase "pin configuration node".

The pin configuration nodes act as a container for an arbitrary number of
subnodes. Each of these subnodes represents some desired configuration for a
pin or a list of pins. This configuration can include the
mux function to select on those pin(s), and various pin configuration
parameters, as listed below.


SUBNODES:

The name of each subnode is not important; all subnodes should be enumerated
and processed purely based on their content.

Each subnode only affects those parameters that are explicitly listed. In
other words, a subnode that lists a mux function but no pin configuration
parameters implies no information about any pin configuration parameters.
Similarly, a pin subnode that describes a pullup parameter implies no
information about e.g. the mux function.

The following generic properties as defined in pinctrl-bindings.txt are valid
to specify in a pin configuration subnode:

- pins:
	Usage: required
	Value type: <string-array>
	Definition: List of gpio pins affected by the properties specified in
		    this subnode.  Valid pins are:
		    gpio1-gpio5 for wcd9340

- bias-disable:
	Usage: optional
	Value type: <none>
	Definition: The specified pins should be configured as no pull.

- bias-pull-down:
	Usage: optional
	Value type: <none>
	Definition: The specified pins should be configured as pull down.

- bias-pull-up:
	Usage: optional
	Value type: <empty>
	Definition: The specified pins should be configured as pull up.

- qcom,pull-up-strength:
	Usage: optional
	Value type: <u32>
	Definition: Specifies the strength to use for pull up, if selected.

- bias-high-impedance:
	Usage: optional
	Value type: <none>
	Definition: The specified pins will put in high-Z mode and disabled.

- input-enable:
	Usage: optional
	Value type: <none>
	Definition: The specified pins are put in input mode.

- output-high:
	Usage: optional
	Value type: <none>
	Definition: The specified pins are configured in output mode, driven
		    high.

- output-low:
	Usage: optional
	Value type: <none>
	Definition: The specified pins are configured in output mode, driven
		    low.

- qcom,drive-strength:
	Usage: optional
	Value type: <u32>
	Definition: Selects the drive strength for the specified pins.

Example:

	wcd: wcd_pinctrl@5 {
		compatible = "qcom,wcd-pinctl";
		qcom,num-gpios = <5>
		gpio-controller;
		#gpio-cells = <2>;

		spkr_1_wcd_en_active: spkr_1_wcd_en_active {
			mux {
				pins = "gpio2";
			};

			config {
				pins = "gpio2";
				output-high;
			};
		};

		spkr_1_wcd_en_sleep: spkr_1_wcd_en_sleep {
			mux {
				pins = "gpio2";
			};

			config {
				pins = "gpio2";
				input-enable;
			};
		};
	};
