microchip,xec-pinctrl

Vendor: Microchip Technology Inc.

Description

Microchip XEC Pin controller Node
Based on pincfg-node.yaml binding.
The MCHP XEC pin controller is a singleton node responsible for controlling
pin function selection and pin properties. For example, you can use this
node to select peripheral pin functions.

The node has the 'pinctrl' node label set in your SoC's devicetree,
so you can modify it like this:

  &pinctrl {
          /* your modifications go here */
  };

All device pin configurations should be placed in child nodes of the
'pinctrl' node, as in the spi0 example shown at the end:

A group can also specify shared pin properties common to all the specified
pins, such as the 'bias-pull-up' property in group 2. Here is a list of
supported standard pin properties:

- bias-disable: Disable pull-up/down (default behavior, not required).
- bias-pull-down: Enable pull-down resistor.
- bias-pull-up: Enable pull-up resistor.
- drive-push-pull: Output driver is push-pull (default, not required).
- drive-open-drain: Output driver is open-drain.
- output-high: Set output state high when pin configured.
- output-low: Set output state low when pin configured.

Custom pin properties for drive strength and slew rate are available:
- drive-strength
- slew-rate

Driver strength and slew rate hardware defaults vary by SoC and pin.

An example for MEC172x family, include the chip level pinctrl
DTSI file in the board level DTS:

  #include <microchip/mec172x/mec172xnsz-pinctrl.dtsi>

We want to use the shared SPI port of the MEC172x QMSPI controller
and want the chip select 0 to be open-drain.

To change a pin's pinctrl default properties add a reference to the
pin in the board's DTS file and set the properties.

  &spi0 {
    pinctrl-0 = < &shd_cs0_n_gpio055
                  &shd_clk_gpio056
                  &shd_io0_gpio223
                  &shd_io1_gpio224
                  &shd_io3_gpio016 >;
    pinctrl-names = "default";
  }

  &shd_cs0_n_gpio055 {
    drive-open-drain;
  };

Properties

Top level properties

These property descriptions apply to “microchip,xec-pinctrl” nodes themselves. This page also describes child node properties in the following sections.

Properties not inherited from the base binding file.

(None)

Child node properties

Name

Type

Details

pinmux

int

Pinmux selection

This property is required.

slew-rate

string

Pin speed. The default value of slew-rate is the SoC power-on-reset
value. Please refer to the data sheet as a small number of pins
may have a different default and some pins do not implement
slew rate adjustment.

Default value: low-speed

Legal values: 'low-speed', 'high-speed'

drive-strength

string

Pin output drive strength for PIO and PIO-24 pin types. Default
is "1x" for most pins. PIO pins are 2, 4, 8, or 12 mA. PIO-24 pins
are 4, 8, 16, or 24 mA. Please refer to the data sheet for each
pin's PIO type and default drive strength.

Default value: 1x

Legal values: '1x', '2x', '4x', '6x'

microchip,output-func-invert

boolean

Invert polarity of an output alternate function. Input functions are not affected.

bias-disable

boolean

disable any pin bias

bias-pull-up

boolean

enable pull-up resistor

bias-pull-down

boolean

enable pull-down resistor

drive-push-pull

boolean

drive actively high and low

drive-open-drain

boolean

drive with open drain (hardware AND)

low-power-enable

boolean

enable low power mode

output-low

boolean

set the pin to output mode with low level

output-high

boolean

set the pin to output mode with high level