152f171abSAndreas Klinger# SPDX-License-Identifier: GPL-2.0 252f171abSAndreas Klinger%YAML 1.2 352f171abSAndreas Klinger--- 452f171abSAndreas Klinger$id: http://devicetree.org/schemas/iio/proximity/devantech-srf04.yaml# 552f171abSAndreas Klinger$schema: http://devicetree.org/meta-schemas/core.yaml# 652f171abSAndreas Klinger 7d6edf95aSAndreas Klingertitle: Devantech SRF04 and Maxbotix mb1000 ultrasonic range finder 852f171abSAndreas Klinger 952f171abSAndreas Klingermaintainers: 1052f171abSAndreas Klinger - Andreas Klinger <ak@it-klinger.de> 1152f171abSAndreas Klinger 1252f171abSAndreas Klingerdescription: | 1352f171abSAndreas Klinger Bit-banging driver using two GPIOs: 1452f171abSAndreas Klinger - trigger-gpio is raised by the driver to start sending out an ultrasonic 1552f171abSAndreas Klinger burst 1652f171abSAndreas Klinger - echo-gpio is held high by the sensor after sending ultrasonic burst 1752f171abSAndreas Klinger until it is received once again 1852f171abSAndreas Klinger 19d6edf95aSAndreas Klinger Specifications about the devices can be found at: 2052f171abSAndreas Klinger http://www.robot-electronics.co.uk/htm/srf04tech.htm 2152f171abSAndreas Klinger 22d6edf95aSAndreas Klinger http://www.maxbotix.com/documents/LV-MaxSonar-EZ_Datasheet.pdf 23d6edf95aSAndreas Klinger 2452f171abSAndreas Klingerproperties: 2552f171abSAndreas Klinger compatible: 26d6edf95aSAndreas Klinger enum: 27d6edf95aSAndreas Klinger - devantech,srf04 28d6edf95aSAndreas Klinger - maxbotix,mb1000 29d6edf95aSAndreas Klinger - maxbotix,mb1010 30d6edf95aSAndreas Klinger - maxbotix,mb1020 31d6edf95aSAndreas Klinger - maxbotix,mb1030 32d6edf95aSAndreas Klinger - maxbotix,mb1040 3352f171abSAndreas Klinger 3452f171abSAndreas Klinger trig-gpios: 3552f171abSAndreas Klinger description: 36d6edf95aSAndreas Klinger Definition of the GPIO for the triggering (output) 37d6edf95aSAndreas Klinger This GPIO is set for about 10 us by the driver to tell the device it 38d6edf95aSAndreas Klinger should initiate the measurement cycle. 39d6edf95aSAndreas Klinger See Documentation/devicetree/bindings/gpio/gpio.txt for information 40d6edf95aSAndreas Klinger on how to specify a consumer gpio. 4152f171abSAndreas Klinger maxItems: 1 4252f171abSAndreas Klinger 4352f171abSAndreas Klinger echo-gpios: 4452f171abSAndreas Klinger description: 4552f171abSAndreas Klinger Definition of the GPIO for the echo (input) 4652f171abSAndreas Klinger This GPIO is set by the device as soon as an ultrasonic burst is sent 4752f171abSAndreas Klinger out and reset when the first echo is received. 4852f171abSAndreas Klinger Thus this GPIO is set while the ultrasonic waves are doing one round 4952f171abSAndreas Klinger trip. 5052f171abSAndreas Klinger It needs to be an GPIO which is able to deliver an interrupt because 5152f171abSAndreas Klinger the time between two interrupts is measured in the driver. 5252f171abSAndreas Klinger maxItems: 1 5352f171abSAndreas Klinger 5452f171abSAndreas Klingerrequired: 5552f171abSAndreas Klinger - compatible 5652f171abSAndreas Klinger - trig-gpios 5752f171abSAndreas Klinger - echo-gpios 5852f171abSAndreas Klinger 5952f171abSAndreas Klingerexamples: 6052f171abSAndreas Klinger - | 6152f171abSAndreas Klinger #include <dt-bindings/gpio/gpio.h> 6252f171abSAndreas Klinger proximity { 6352f171abSAndreas Klinger compatible = "devantech,srf04"; 6452f171abSAndreas Klinger trig-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH>; 6552f171abSAndreas Klinger echo-gpios = <&gpio2 6 GPIO_ACTIVE_HIGH>; 6652f171abSAndreas Klinger }; 67