| * Devantech SRF04 ultrasonic range finder |
| Bit-banging driver using two GPIOs |
| |
| Required properties: |
| - compatible: Should be "devantech,srf04" |
| |
| - trig-gpios: 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. |
| |
| - echo-gpios: 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. |
| See Documentation/devicetree/bindings/gpio/gpio.txt for |
| information on how to specify a consumer gpio. |
| |
| Example: |
| srf04@0 { |
| compatible = "devantech,srf04"; |
| trig-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH>; |
| echo-gpios = <&gpio2 6 GPIO_ACTIVE_HIGH>; |
| }; |
