Specific GPIO pin is connected to switch, upon pressing the switch the ISR needs to triggeredSo I have the userspace application to read the ISR, but i am getting the ISR on both the edges.
Receiving the interrupt when switch is pressed and also when released. How to configure to receive the ISR only on rising edge
#include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <unistd.h> #include <poll.h> int main(int argc, char *argv[]){ int fd; char value; struct pollfd poll_gpio; poll_gpio.events = POLLPRI; // export GPIO fd = open ("/sys/class/gpio/export", O_WRONLY); write (fd, "44", 4); close (fd); // configure as input fd = open ("/sys/class/gpio/gpio44/direction", O_WRONLY); write (fd, "in", 3); close (fd); // configure interrupt fd = open ("/sys/class/gpio/gpio44/edge", O_WRONLY); write (fd, "rising", 7); // configure as rising edge close (fd); // open value file fd = open("/sys/class/gpio/gpio44/value", O_RDONLY ); poll_gpio.fd = fd; poll (&poll_gpio, 1, -1); // discard first IRQ read (fd, &value, 1); // wait for interrupt while (1){ poll (&poll_gpio, 1, -1); if ((poll_gpio.revents & POLLPRI) == POLLPRI){ lseek(fd, 0, SEEK_SET); read (fd, &value, 1); usleep (50); printf("Interrupt GPIO val: %c\n", value); }} close(fd); //close value file return EXIT_SUCCESS; }
