1*c66ec88fSEmmanuel VadotDevice-Tree Bindings for a PPS Signal on GPIO 2*c66ec88fSEmmanuel Vadot 3*c66ec88fSEmmanuel VadotThese properties describe a PPS (pulse-per-second) signal connected to 4*c66ec88fSEmmanuel Vadota GPIO pin. 5*c66ec88fSEmmanuel Vadot 6*c66ec88fSEmmanuel VadotRequired properties: 7*c66ec88fSEmmanuel Vadot- compatible: should be "pps-gpio" 8*c66ec88fSEmmanuel Vadot- gpios: one PPS GPIO in the format described by ../gpio/gpio.txt 9*c66ec88fSEmmanuel Vadot 10*c66ec88fSEmmanuel VadotAdditional required properties for the PPS ECHO functionality: 11*c66ec88fSEmmanuel Vadot- echo-gpios: one PPS ECHO GPIO in the format described by ../gpio/gpio.txt 12*c66ec88fSEmmanuel Vadot- echo-active-ms: duration in ms of the active portion of the echo pulse 13*c66ec88fSEmmanuel Vadot 14*c66ec88fSEmmanuel VadotOptional properties: 15*c66ec88fSEmmanuel Vadot- assert-falling-edge: when present, assert is indicated by a falling edge 16*c66ec88fSEmmanuel Vadot (instead of by a rising edge) 17*c66ec88fSEmmanuel Vadot 18*c66ec88fSEmmanuel VadotExample: 19*c66ec88fSEmmanuel Vadot pps { 20*c66ec88fSEmmanuel Vadot pinctrl-names = "default"; 21*c66ec88fSEmmanuel Vadot pinctrl-0 = <&pinctrl_pps>; 22*c66ec88fSEmmanuel Vadot 23*c66ec88fSEmmanuel Vadot gpios = <&gpio1 26 GPIO_ACTIVE_HIGH>; 24*c66ec88fSEmmanuel Vadot assert-falling-edge; 25*c66ec88fSEmmanuel Vadot 26*c66ec88fSEmmanuel Vadot echo-gpios = <&gpio1 27 GPIO_ACTIVE_HIGH>; 27*c66ec88fSEmmanuel Vadot echo-active-ms = <100>; 28*c66ec88fSEmmanuel Vadot 29*c66ec88fSEmmanuel Vadot compatible = "pps-gpio"; 30*c66ec88fSEmmanuel Vadot }; 31