arm,mps2-pinctrl

Vendor: ARM Ltd.

Description

The Arm Mps2 pin controller is a node responsible for controlling
pin function selection and pin properties, such as routing a UART3 TX
to pin 1.

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 shown in this example:

  &pinctrl {
    /* configuration for the usart0 "default" state */
    uart3_default: uart3_default {
      /* group 1 */
      group1 {
        /* configure P1 as UART3 TX */
        pinmux = <UART3_TXD_EXP>;
      };
      /* group 2 */
      group2 {
        /* configure P0 as UART3 RX */
        pinmux = <UART3_RXD_EXP>;
        /* enable input on pin 1 */
        input-enable;
      };
    };
  };

The 'uart3_default' child node encodes the pin configurations for a
particular state of a device; in this case, the default (that is, active)
state.

As shown, pin configurations are organized in groups within each child node.
Each group can specify a list of pin function selections in the 'pinmux'
property. Here is a list of supported standard pin properties:
- input-enable

A group can also specify shared pin properties common to all the specified
pins, such as the 'input-enable' property in group 2.

To link pin configurations with a device, use a pinctrl-N property for some
number N, like this example you could place in your board's DTS file:

   #include "board-pinctrl.dtsi"

   &uart3 {
         pinctrl-0 = <&uart3_default>;
         pinctrl-1 = <&uart3_sleep>;
         pinctrl-names = "default", "sleep";
   };

Properties

Top level properties

These property descriptions apply to “arm,mps2-pinctrl” nodes themselves. This page also describes child node properties in the following sections.

Properties not inherited from the base binding file.

(None)

Grandchild node properties

Name

Type

Details

pinmux

array

An array of pins sharing the same group properties. Each
element of the array is an integer constructed from the
pin number and the alternative function of the pin.

This property is required.

input-enable

boolean

enable input on pin (e.g. enable an input buffer, no effect on output)