renesas,ra8-pinctrl

Vendor: Renesas Electronics Corporation

Description

The Renesas RA pin controller is a node responsible for controlling
pin function selection and pin properties, such as routing a SCI0 RXD
to P610.

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:

  /* You can put this in places like a board-pinctrl.dtsi file in
   * your board directory, or a devicetree overlay in your application.
   */

  /* include pre-defined combinations for the SoC variant used by the board */
  #include <dt-bindings/pinctrl/renesas/ra-pinctrl.h>

  &pinctrl {
    /* configuration for the sci0 "default" state */
      sci0_default: sci0_default {
      group1 {
        /* tx */
        psels = <RA_PSEL(RA_PSEL_SCI_0, 6, 9)>;
        drive-strength = "medium";
      };
      group2 {
        /* rx */
        psels = <RA_PSEL(RA_PSEL_SCI_0, 6, 10)>;
      };
    };
  };

The 'sci0_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 'psels'
property.

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

- bias-disable: Disable pull-up/down (default, not required).
- bias-pull-up: Enable pull-up resistor.
- input-enable: Enable input from the pin.
- drive-strength: Set the drive strength of the pin. Possible
  values are: low, medium, highspeed-high, high.

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"

   &sci0 {
         pinctrl-0 = <&uart0_default>;
         pinctrl-1 = <&uart0_sleep>;
         pinctrl-names = "default", "sleep";
   };

Properties

Top level properties

These property descriptions apply to “renesas,ra8-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

bias-disable

boolean

disable any pin bias

bias-pull-up

boolean

enable pull-up resistor

drive-open-drain

boolean

drive with open drain (hardware AND)

input-enable

boolean

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

psels

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.

drive-strength

string

The drive strength of a pin. The default value is low, as this
is the power on reset value.

Default value: low

Legal values: 'low', 'medium', 'highspeed-high', 'high'