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Diffstat (limited to 'Documentation/devicetree/bindings/iio/proximity/devantech-srf04.yaml')
-rw-r--r-- | Documentation/devicetree/bindings/iio/proximity/devantech-srf04.yaml | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/iio/proximity/devantech-srf04.yaml b/Documentation/devicetree/bindings/iio/proximity/devantech-srf04.yaml new file mode 100644 index 000000000..ce7952798 --- /dev/null +++ b/Documentation/devicetree/bindings/iio/proximity/devantech-srf04.yaml @@ -0,0 +1,86 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/proximity/devantech-srf04.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Devantech SRF04 and Maxbotix mb1000 ultrasonic range finder + +maintainers: + - Andreas Klinger <ak@it-klinger.de> + +description: | + Bit-banging driver using two GPIOs: + - trigger-gpio is raised by the driver to start sending out an ultrasonic + burst + - echo-gpio is held high by the sensor after sending ultrasonic burst + until it is received once again + + Specifications about the devices can be found at: + https://www.robot-electronics.co.uk/htm/srf04tech.htm + + https://www.maxbotix.com/documents/LV-MaxSonar-EZ_Datasheet.pdf + +properties: + compatible: + enum: + - devantech,srf04 + - maxbotix,mb1000 + - maxbotix,mb1010 + - maxbotix,mb1020 + - maxbotix,mb1030 + - maxbotix,mb1040 + + trig-gpios: + description: + Definition of the GPIO for the triggering (output) + This GPIO is set for about 10 us by the driver to tell the device it + should initiate the measurement cycle. + See Documentation/devicetree/bindings/gpio/gpio.txt for information + on how to specify a consumer gpio. + maxItems: 1 + + echo-gpios: + description: + Definition of the GPIO for the echo (input) + This GPIO is set by the device as soon as an ultrasonic burst is sent + out and reset when the first echo is received. + Thus this GPIO is set while the ultrasonic waves are doing one round + trip. + It needs to be an GPIO which is able to deliver an interrupt because + the time between two interrupts is measured in the driver. + maxItems: 1 + + power-gpios: + description: + Definition of the GPIO for power management of connected peripheral + (output). + This GPIO can be used by the external hardware for power management. + When the device gets suspended it's switched off and when it resumes + it's switched on again. After some period of inactivity the driver + get suspended automatically (autosuspend feature). + maxItems: 1 + + startup-time-ms: + description: + This is the startup time the device needs after a resume to be up and + running. + minimum: 0 + maximum: 1000 + default: 100 + +required: + - compatible + - trig-gpios + - echo-gpios + +additionalProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + proximity { + compatible = "devantech,srf04"; + trig-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH>; + echo-gpios = <&gpio2 6 GPIO_ACTIVE_HIGH>; + }; |