1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* Real Time Clock Driver Test 3 * by: Benjamin Gaignard (benjamin.gaignard@linaro.org) 4 * 5 * To build 6 * gcc rtctest_setdate.c -o rtctest_setdate 7 */ 8 9 #include <stdio.h> 10 #include <linux/rtc.h> 11 #include <sys/ioctl.h> 12 #include <sys/time.h> 13 #include <sys/types.h> 14 #include <fcntl.h> 15 #include <unistd.h> 16 #include <stdlib.h> 17 #include <errno.h> 18 19 static const char default_time[] = "00:00:00"; 20 21 int main(int argc, char **argv) 22 { 23 int fd, retval; 24 struct rtc_time new, current; 25 const char *rtc, *date; 26 const char *time = default_time; 27 28 switch (argc) { 29 case 4: 30 time = argv[3]; 31 /* FALLTHROUGH */ 32 case 3: 33 date = argv[2]; 34 rtc = argv[1]; 35 break; 36 default: 37 fprintf(stderr, "usage: rtctest_setdate <rtcdev> <DD-MM-YYYY> [HH:MM:SS]\n"); 38 return 1; 39 } 40 41 fd = open(rtc, O_RDONLY); 42 if (fd == -1) { 43 perror(rtc); 44 exit(errno); 45 } 46 47 sscanf(date, "%d-%d-%d", &new.tm_mday, &new.tm_mon, &new.tm_year); 48 new.tm_mon -= 1; 49 new.tm_year -= 1900; 50 sscanf(time, "%d:%d:%d", &new.tm_hour, &new.tm_min, &new.tm_sec); 51 52 fprintf(stderr, "Test will set RTC date/time to %d-%d-%d, %02d:%02d:%02d.\n", 53 new.tm_mday, new.tm_mon + 1, new.tm_year + 1900, 54 new.tm_hour, new.tm_min, new.tm_sec); 55 56 /* Write the new date in RTC */ 57 retval = ioctl(fd, RTC_SET_TIME, &new); 58 if (retval == -1) { 59 perror("RTC_SET_TIME ioctl"); 60 close(fd); 61 exit(errno); 62 } 63 64 /* Read back */ 65 retval = ioctl(fd, RTC_RD_TIME, ¤t); 66 if (retval == -1) { 67 perror("RTC_RD_TIME ioctl"); 68 exit(errno); 69 } 70 71 fprintf(stderr, "\n\nCurrent RTC date/time is %d-%d-%d, %02d:%02d:%02d.\n", 72 current.tm_mday, current.tm_mon + 1, current.tm_year + 1900, 73 current.tm_hour, current.tm_min, current.tm_sec); 74 75 close(fd); 76 return 0; 77 } 78