xref: /linux/Documentation/devicetree/bindings/iio/proximity/devantech-srf04.yaml (revision 26fbb4c8c7c3ee9a4c3b4de555a8587b5a19154e) 
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  https://www.robot-electronics.co.uk/htm/srf04tech.htm
21
22  https://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
54  power-gpios:
55    description:
56      Definition of the GPIO for power management of connected peripheral
57      (output).
58      This GPIO can be used by the external hardware for power management.
59      When the device gets suspended it's switched off and when it resumes
60      it's switched on again. After some period of inactivity the driver
61      get suspended automatically (autosuspend feature).
62    maxItems: 1
63
64  startup-time-ms:
65    description:
66      This is the startup time the device needs after a resume to be up and
67      running.
68    minimum: 0
69    maximum: 1000
70    default: 100
71
72required:
73  - compatible
74  - trig-gpios
75  - echo-gpios
76
77additionalProperties: false
78
79examples:
80  - |
81    #include <dt-bindings/gpio/gpio.h>
82    proximity {
83        compatible = "devantech,srf04";
84        trig-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH>;
85        echo-gpios = <&gpio2  6 GPIO_ACTIVE_HIGH>;
86    };
87