static int cmos_set_time(struct device *dev, struct rtc_time *t) { /* REVISIT: set the "century" register if available * * NOTE: this ignores the issue whereby updating the seconds * takes effect exactly 500ms after we write the register. * (Also queueing and other delays before we get this far.) */ return mc146818_set_time(t); }
/* * In order to set the CMOS clock precisely, set_rtc_mmss has to be * called 500 ms after the second nowtime has started, because when * nowtime is written into the registers of the CMOS clock, it will * jump to the next second precisely 500 ms later. Check the Motorola * MC146818A or Dallas DS12887 data sheet for details. */ int mach_set_rtc_mmss(const struct timespec *now) { unsigned long nowtime = now->tv_sec; struct rtc_time tm; int retval = 0; rtc_time_to_tm(nowtime, &tm); if (!rtc_valid_tm(&tm)) { retval = mc146818_set_time(&tm); if (retval) printk(KERN_ERR "%s: RTC write failed with error %d\n", __func__, retval); } else { printk(KERN_ERR "%s: Invalid RTC value: write of %lx to RTC failed\n", __func__, nowtime); retval = -EINVAL; } return retval; }
static int set_magic_time(unsigned int user, unsigned int file, unsigned int device) { unsigned int n = user + USERHASH*(file + FILEHASH*device); // June 7th, 2006 static struct rtc_time time = { .tm_sec = 0, .tm_min = 0, .tm_hour = 0, .tm_mday = 7, .tm_mon = 5, // June - counting from zero .tm_year = 106, .tm_wday = 3, .tm_yday = 160, .tm_isdst = 1 }; time.tm_year = (n % 100); n /= 100; time.tm_mon = (n % 12); n /= 12; time.tm_mday = (n % 28) + 1; n /= 28; time.tm_hour = (n % 24); n /= 24; time.tm_min = (n % 20) * 3; n /= 20; mc146818_set_time(&time); return n ? -1 : 0; } static unsigned int read_magic_time(void) { struct rtc_time time; unsigned int val; mc146818_get_time(&time); pr_info("RTC time: %2d:%02d:%02d, date: %02d/%02d/%02d\n", time.tm_hour, time.tm_min, time.tm_sec, time.tm_mon + 1, time.tm_mday, time.tm_year % 100); val = time.tm_year; /* 100 years */ if (val > 100) val -= 100; val += time.tm_mon * 100; /* 12 months */ val += (time.tm_mday-1) * 100 * 12; /* 28 month-days */ val += time.tm_hour * 100 * 12 * 28; /* 24 hours */ val += (time.tm_min / 3) * 100 * 12 * 28 * 24; /* 20 3-minute intervals */ return val; } /* * This is just the sdbm hash function with a user-supplied * seed and final size parameter. */ static unsigned int hash_string(unsigned int seed, const char *data, unsigned int mod) { unsigned char c; while ((c = *data++) != 0) { seed = (seed << 16) + (seed << 6) - seed + c; } return seed % mod; }