This is the documentation for the latest (main) development branch of Zephyr. If you are looking for the documentation of previous releases, use the drop-down menu on the left and select the desired version.

zephyr,w1-gpio

Vendor: Zephyr-specific binding

Description

These nodes are “w1” bus nodes.

Zephyr W1 GPIO node

This defines a one-wire driver through GPIO bit-banging.

For example:

/ {
      w1: w1 {
               compatible = "zephyr,w1-gpio";
               gpios = <&gpio0 13 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN | GPIO_PULL_UP)>;
       };
};

Above:
  - w1 is pin 13 on gpio0. The gpio is active when the pin is high, is
    configured as an open-drain, and has a pull-up resistor.

Implementation details:
  - Most drivers require the selected gpio to support open drain, this enables onewire
    devices to lower the signal when the SOC set the signal high.
  - Ensure pullup is strong enough (4.7K according to the specification). Standard pullup in
    SOC are usually weak, and may not be strong enough.

Properties

Properties not inherited from the base binding file.

Name

Type

Details

active-pullup

boolean

Enable the active pullup for the 1-Wire bus.

gpios

phandle-array

This property is required.