linux硬件看门狗，只需打开/dev/watchdog设备操作就可以。如果dev目录下没有看门狗设备，则需要去内核配置打开看门狗相应功能。
#include <stdio.h> #include <stdlib.h> #include <string.h> #include <fcntl.h> #include <sys/ioctl.h> #include <sys/signal.h> #define WATCHDOG_IOCTL_BASE 'W' #define WDIOC_SETOPTIONS _IOR(WATCHDOG_IOCTL_BASE, 4, int) #define WDIOC_SETTIMEOUT _IOWR(WATCHDOG_IOCTL_BASE, 6, int) #define WDIOC_KEEPALIVE _IOR(WATCHDOG_IOCTL_BASE, 5, int) #define WDIOC_GETTIMEOUT _IOR(WATCHDOG_IOCTL_BASE, 7, int) #define WDIOS_DISABLECARD 0x0001 /* Turn off the watchdog timer */ #define WDIOS_ENABLECARD 0x0002 /* Turn on the watchdog timer */ int wdt_fd = -1; int WatchdogStop(void) { if (wdt_fd == -1){ printf("WatchdogStop fail to open watchdog device\n"); return -1; } int option = WDIOS_DISABLECARD; ioctl(wdt_fd, WDIOC_SETOPTIONS, &option); if (wdt_fd != -1){ close(wdt_fd); wdt_fd = -1; } return 0; } int WatchdogOpen(void) { wdt_fd = open("/dev/watchdog", O_WRONLY); if (wdt_fd == -1){ printf("fail to open watchdog device %d\n",wdt_fd); } return wdt_fd; } int WatchdogSetTimeout(int time) { if (wdt_fd == -1){ printf("WatchdogSetTimeout fail to open watchdog device\n"); return -1; } ioctl(wdt_fd, WDIOC_SETTIMEOUT, &time); return 0; } int WatchdogSetKeepAlive(void) { if (wdt_fd == -1){ printf("WatchdogKeepAlive fail to open watchdog device\n"); return -1; } ioctl(wdt_fd, WDIOC_KEEPALIVE, 0); return 0; } void psdk_watch_dog_get_timeout(int *time) { ioctl(wdt_fd, WDIOC_GETTIMEOUT, &time); } void *WatchdogExit(void) { WatchdogStop(); exit(0) ; } int main(int argc, char* argv[]) { int time=5; long long itime=0; char ctrltype[32]={0}; if(argc > 1){ strcpy(ctrltype,argv[1]); printf("ctrl:%s\n",ctrltype); }else{ printf("===================\n"); printf("watchdog [start/stop] [time]\n"); printf("===================\n"); return -1; } signal(SIGINT, WatchdogExit); if(strcmp("stop",ctrltype)==0){ WatchdogOpen(); WatchdogStop(); return 0; }else if(strcmp("start",ctrltype)==0){ if(argc == 3) { char times[32]={0}; strcpy(times,argv[2]); time = atoi(times); } printf("timeout:%ds\n",time); }else{ printf("===================\n"); printf("watchdog [start/stop] [time]\n"); printf("===================\n"); return -1; } WatchdogOpen(); if(time > 0){ WatchdogSetTimeout(time); }else{ printf("WatchdogSetTimeout err\n"); return -1; } itime = (time*1000*1000)/2; while(1) { WatchdogSetKeepAlive(); usleep(itime); } return 0; }
