pinctrl-tz1090-pdc: add TZ1090 PDC pinctrl driver

ImgTec TZ1090 PDC pin controller

Required properties:

- compatible: "img,tz1090-pdc-pinctrl"

- reg: Should contain the register physical address and length of the

  SOC_GPIO_CONTROL registers in the PDC register region.

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".

TZ1090-PDC's pin configuration nodes act as a container for an abitrary number

of subnodes. Each of these subnodes represents some desired configuration for a

pin, a group, or a list of pins or groups. This configuration can include the

mux function to select on those pin(s)/group(s), and various pin configuration

parameters, such as pull-up, drive strength, etc.

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. For this reason, even seemingly boolean

values are actually tristates in this binding: unspecified, off, or on.

Unspecified is represented as an absent property, and off/on are represented as

integer values 0 and 1.

Required subnode-properties:

- tz1090,pins : An array of strings. Each string contains the name of a pin or

  group. Valid values for these names are listed below.

Optional subnode-properties:

- tz1090,function: A string containing the name of the function to mux to the

  pin or group. Valid values for function names are listed below, including

  which pingroups can be muxed to them.

- supported generic pinconfig properties (for further details see

  Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt):

  - bias-disable

  - bias-high-impedance

  - bias-bus-hold

  - bias-pull-up

  - bias-pull-down

  - input-schmitt-enable

  - input-schmitt-disable

  - slew-rate: Integer, control slew rate of pins.

      0: slow (half frequency)

      1: fast

  - drive-strength: Integer, control drive strength of pins in mA.

      2: 2mA

      4: 4mA

      8: 8mA

      12: 12mA

  - low-power-enable: Flag, power-on-start weak pull-down for invalid power.

  - low-power-disable: Flag, power-on-start weak pull-down disabled.

Note that many of these properties are only valid for certain specific pins

or groups. See the TZ1090 TRM for complete details regarding which groups

support which functionality. The Linux pinctrl driver may also be a useful

reference.

Valid values for pin and group names are:

  pins:

    These all support bias-high-impediance, bias-pull-up, bias-pull-down, and

    bias-bus-hold (which can also be provided to any of the groups below to set

    it for all gpio pins in that group).

    gpio0, gpio1, sys_wake0, sys_wake1, sys_wake2, ir_data, ext_power.

  mux groups:

    These all support function.

    gpio0

        pins:       gpio0.

        function:   ir_mod_stable_out.

    gpio1

        pins:       gpio1.

        function:   ir_mod_power_out.

  drive groups:

    These support input-schmitt-enable, input-schmitt-disable, slew-rate,

    drive-strength, low-power-enable, and low-power-disable.

    pdc

        pins:   gpio0, gpio1, sys_wake0, sys_wake1, sys_wake2, ir_data,

                ext_power.

Example:

	pinctrl_pdc: pinctrl@02006500 {

		#gpio-range-cells = <3>;

		compatible = "img,tz1090-pdc-pinctrl";

		reg = <0x02006500 0x100>;

	};

Example board file extracts:

	&pinctrl_pdc {

		pinctrl-names = "default";

		pinctrl-0 = <&syswake_default>;

		syswake_default: syswakes {

			syswake_cfg {

				tz1090,pins =	"sys_wake0",

						"sys_wake1",

						"sys_wake2";

				pull-up;

			};

		};

		irmod_default: irmod {

			gpio0_cfg {

				tz1090,pins =	"gpio0";

				tz1090,function = "ir_mod_stable_out";

			};

			gpio1_cfg {

				tz1090,pins =	"gpio1";

				tz1090,function = "ir_mod_power_out";

			};

		};

	};

	ir: ir@02006200 {

		pinctrl-names = "default";

		pinctrl-0 = <&irmod_default>;

	};

	select PINMUX

	select GENERIC_PINCONF

config PINCTRL_TZ1090_PDC

	bool "Toumaz Xenif TZ1090 PDC pin control driver"

	depends on SOC_TZ1090

	select PINMUX

	select PINCONF

config PINCTRL_U300

	bool "U300 pin controller driver"

	depends on ARCH_U300

obj-$(CONFIG_PINCTRL_TEGRA30)	+= pinctrl-tegra30.o

obj-$(CONFIG_PINCTRL_TEGRA114)	+= pinctrl-tegra114.o

obj-$(CONFIG_PINCTRL_TZ1090)	+= pinctrl-tz1090.o

obj-$(CONFIG_PINCTRL_TZ1090_PDC)	+= pinctrl-tz1090-pdc.o

obj-$(CONFIG_PINCTRL_U300)	+= pinctrl-u300.o

obj-$(CONFIG_PINCTRL_COH901)	+= pinctrl-coh901.o

obj-$(CONFIG_PINCTRL_SAMSUNG)	+= pinctrl-samsung.o