1# SPDX-License-Identifier: GPL-2.0 2%YAML 1.2 3--- 4$id: http://devicetree.org/schemas/iio/proximity/devantech-srf04.yaml# 5$schema: http://devicetree.org/meta-schemas/core.yaml# 6 7title: Devantech SRF04 and Maxbotix mb1000 ultrasonic range finder 8 9maintainers: 10 - Andreas Klinger <ak@it-klinger.de> 11 12description: | 13 Bit-banging driver using two GPIOs: 14 - trigger-gpio is raised by the driver to start sending out an ultrasonic 15 burst 16 - echo-gpio is held high by the sensor after sending ultrasonic burst 17 until it is received once again 18 19 Specifications about the devices can be found at: 20 http://www.robot-electronics.co.uk/htm/srf04tech.htm 21 22 http://www.maxbotix.com/documents/LV-MaxSonar-EZ_Datasheet.pdf 23 24properties: 25 compatible: 26 enum: 27 - devantech,srf04 28 - maxbotix,mb1000 29 - maxbotix,mb1010 30 - maxbotix,mb1020 31 - maxbotix,mb1030 32 - maxbotix,mb1040 33 34 trig-gpios: 35 description: 36 Definition of the GPIO for the triggering (output) 37 This GPIO is set for about 10 us by the driver to tell the device it 38 should initiate the measurement cycle. 39 See Documentation/devicetree/bindings/gpio/gpio.txt for information 40 on how to specify a consumer gpio. 41 maxItems: 1 42 43 echo-gpios: 44 description: 45 Definition of the GPIO for the echo (input) 46 This GPIO is set by the device as soon as an ultrasonic burst is sent 47 out and reset when the first echo is received. 48 Thus this GPIO is set while the ultrasonic waves are doing one round 49 trip. 50 It needs to be an GPIO which is able to deliver an interrupt because 51 the time between two interrupts is measured in the driver. 52 maxItems: 1 53 54required: 55 - compatible 56 - trig-gpios 57 - echo-gpios 58 59examples: 60 - | 61 #include <dt-bindings/gpio/gpio.h> 62 proximity { 63 compatible = "devantech,srf04"; 64 trig-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH>; 65 echo-gpios = <&gpio2 6 GPIO_ACTIVE_HIGH>; 66 }; 67