PPS on GPIO1, LED on GPIO5
/dts-v1/;
/plugin/;
/ {
fragment@0 {
target-path="/";
__overlay__ {
pps: pps {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_pps>;
gpios = <&gpiochip_stub_332 18 0>;
assert-falling-edge;
echo-gpios = <&gpiochip_stub_330 16 0>;
echo-active-ms = <100>;
compatible = "pps-gpio";
};
};
};
};
build with:
dtc -I dts -O dtb -o /home/john/ppsgpio.dtb /home/john/pps-gpio.dts
kernel config options to add
CONFIG_OF=y CONFIG_OF_DYNAMIC=y CONFIG_OF_OVERLAY=y CONFIG_OF_FLATTREE=y CONFIG_OF_CONFIGFS=y CONFIG_OF_GPIO_STUB=y CONFIG_OF_ROOT_STUB=y CONFIG_PPS=y CONFIG_PPS_CLIENT_LDISC=y CONFIG_PPS_CLIENT_GPIO=y CONFIG_GPIO_SYSFS=y