xref: /freebsd/sys/contrib/device-tree/Bindings/iio/proximity/parallax-ping.yaml (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)

# SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/iio/proximity/parallax-ping.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Parallax PING))) and LaserPING range finder

maintainers:
  - Andreas Klinger <ak@it-klinger.de>

description: |
  Bit-banging driver using one GPIO:
  - ping-gpios is raised by the driver to start measurement
  - direction of ping-gpio is then switched into input with an interrupt
    for receiving distance value as PWM signal

  Specifications about the devices can be found at:
  http://parallax.com/sites/default/files/downloads/28041-LaserPING-2m-Rangefinder-Guide.pdf
  http://parallax.com/sites/default/files/downloads/28015-PING-Documentation-v1.6.pdf

properties:
  compatible:
    enum:
      - parallax,ping
      - parallax,laserping

  ping-gpios:
    description:
      Definition of the GPIO for the triggering and echo (output and input)
      This GPIO is set for about 5 us by the driver to tell the device it
      should initiate the measurement cycle. Afterwards the GPIO is switched
      to input direction with an interrupt. The device sets it and the
      length of the input signal corresponds to the measured distance.
      It needs to be an GPIO which is able to deliver an interrupt because
      the time between two interrupts is measured in the driver.
      See Documentation/devicetree/bindings/gpio/gpio.txt for information
      on how to specify a consumer gpio.
    maxItems: 1

required:
  - compatible
  - ping-gpios

additionalProperties: false

examples:
  - |
    #include <dt-bindings/gpio/gpio.h>
    proximity {
        compatible = "parallax,laserping";
        ping-gpios = <&gpio0 26 GPIO_ACTIVE_HIGH>;
    };