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# 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>;
};
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