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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>; }; |