-static const unsigned char days_in_month[] = {
- 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
-};
-
-#define LEAPS_THRU_END_OF(y) ((y)/4 - (y)/100 + (y)/400)
-#define LEAP_YEAR(year) ((!(year % 4) && (year % 100)) || !(year % 400))
-
-static int month_days(unsigned int month, unsigned int year)
-{
- return days_in_month[month] + (LEAP_YEAR(year) && month == 1);
-}
-
-/*
- * Convert seconds since 01-01-1970 00:00:00 to Gregorian date.
- */
-void rtc_time_to_tm(unsigned long time, struct rtc_time *tm)
-{
- int days, month, year;
-
- days = time / 86400;
- time -= days * 86400;
-
- tm->tm_wday = (days + 4) % 7;
-
- year = 1970 + days / 365;
- days -= (year - 1970) * 365
- + LEAPS_THRU_END_OF(year - 1)
- - LEAPS_THRU_END_OF(1970 - 1);
- if (days < 0) {
- year -= 1;
- days += 365 + LEAP_YEAR(year);
- }
- tm->tm_year = year - 1900;
- tm->tm_yday = days + 1;
-
- for (month = 0; month < 11; month++) {
- int newdays;
-
- newdays = days - month_days(month, year);
- if (newdays < 0)
- break;
- days = newdays;
- }
- tm->tm_mon = month;
- tm->tm_mday = days + 1;
-
- tm->tm_hour = time / 3600;
- time -= tm->tm_hour * 3600;
- tm->tm_min = time / 60;
- tm->tm_sec = time - tm->tm_min * 60;
-}
-EXPORT_SYMBOL(rtc_time_to_tm);
-
-/*
- * Convert Gregorian date to seconds since 01-01-1970 00:00:00.
- */
-int rtc_tm_to_time(struct rtc_time *tm, unsigned long *time)
-{
- unsigned int yrs = tm->tm_year + 1900;
-
- *time = 0;
-
- if (yrs < 1970 ||
- tm->tm_mon >= 12 ||
- tm->tm_mday < 1 ||
- tm->tm_mday > month_days(tm->tm_mon, yrs) ||
- tm->tm_hour >= 24 ||
- tm->tm_min >= 60 ||
- tm->tm_sec >= 60)
- return -EINVAL;
-
- *time = mktime(yrs, tm->tm_mon + 1, tm->tm_mday,
- tm->tm_hour, tm->tm_min, tm->tm_sec);
-
- return 0;
-}
-EXPORT_SYMBOL(rtc_tm_to_time);
-