1Device-Tree Bindings for a PPS Signal on GPIO 2 3These properties describe a PPS (pulse-per-second) signal connected to 4a GPIO pin. 5 6Required properties: 7- compatible: should be "pps-gpio" 8- gpios: one PPS GPIO in the format described by ../gpio/gpio.txt 9 10Additional required properties for the PPS ECHO functionality: 11- echo-gpios: one PPS ECHO GPIO in the format described by ../gpio/gpio.txt 12- echo-active-ms: duration in ms of the active portion of the echo pulse 13 14Optional properties: 15- assert-falling-edge: when present, assert is indicated by a falling edge 16 (instead of by a rising edge) 17 18Example: 19 pps { 20 pinctrl-names = "default"; 21 pinctrl-0 = <&pinctrl_pps>; 22 23 gpios = <&gpio1 26 GPIO_ACTIVE_HIGH>; 24 assert-falling-edge; 25 26 echo-gpios = <&gpio1 27 GPIO_ACTIVE_HIGH>; 27 echo-active-ms = <100>; 28 29 compatible = "pps-gpio"; 30 }; 31