^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * rtc and date/time utility functions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2005-06 Tower Technologies
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * Author: Alessandro Zummo <a.zummo@towertech.it>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * based on arch/arm/common/rtctime.c and other bits
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/rtc.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) static const unsigned char rtc_days_in_month[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) static const unsigned short rtc_ydays[2][13] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) /* Normal years */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) /* Leap years */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) #define LEAPS_THRU_END_OF(y) ((y) / 4 - (y) / 100 + (y) / 400)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) * The number of days in the month.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) int rtc_month_days(unsigned int month, unsigned int year)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) return rtc_days_in_month[month] + (is_leap_year(year) && month == 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) EXPORT_SYMBOL(rtc_month_days);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) * The number of days since January 1. (0 to 365)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) int rtc_year_days(unsigned int day, unsigned int month, unsigned int year)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) return rtc_ydays[is_leap_year(year)][month] + day - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) EXPORT_SYMBOL(rtc_year_days);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) * rtc_time64_to_tm - Converts time64_t to rtc_time.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) * Convert seconds since 01-01-1970 00:00:00 to Gregorian date.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) void rtc_time64_to_tm(time64_t time, struct rtc_time *tm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) unsigned int month, year, secs;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) int days;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) /* time must be positive */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) days = div_s64_rem(time, 86400, &secs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) /* day of the week, 1970-01-01 was a Thursday */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) tm->tm_wday = (days + 4) % 7;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) year = 1970 + days / 365;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) days -= (year - 1970) * 365
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) + LEAPS_THRU_END_OF(year - 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) - LEAPS_THRU_END_OF(1970 - 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) while (days < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) year -= 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) days += 365 + is_leap_year(year);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) tm->tm_year = year - 1900;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) tm->tm_yday = days + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) for (month = 0; month < 11; month++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) int newdays;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) newdays = days - rtc_month_days(month, year);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) if (newdays < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) days = newdays;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) tm->tm_mon = month;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) tm->tm_mday = days + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) tm->tm_hour = secs / 3600;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) secs -= tm->tm_hour * 3600;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) tm->tm_min = secs / 60;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) tm->tm_sec = secs - tm->tm_min * 60;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) tm->tm_isdst = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) EXPORT_SYMBOL(rtc_time64_to_tm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) * Does the rtc_time represent a valid date/time?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) int rtc_valid_tm(struct rtc_time *tm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) if (tm->tm_year < 70 ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) tm->tm_year > (INT_MAX - 1900) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) ((unsigned int)tm->tm_mon) >= 12 ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) tm->tm_mday < 1 ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) tm->tm_mday > rtc_month_days(tm->tm_mon,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) ((unsigned int)tm->tm_year + 1900)) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) ((unsigned int)tm->tm_hour) >= 24 ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) ((unsigned int)tm->tm_min) >= 60 ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) ((unsigned int)tm->tm_sec) >= 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) EXPORT_SYMBOL(rtc_valid_tm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) * rtc_tm_to_time64 - Converts rtc_time to time64_t.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) * Convert Gregorian date to seconds since 01-01-1970 00:00:00.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) time64_t rtc_tm_to_time64(struct rtc_time *tm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) return mktime64(((unsigned int)tm->tm_year + 1900), tm->tm_mon + 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) EXPORT_SYMBOL(rtc_tm_to_time64);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) * Convert rtc_time to ktime
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) ktime_t rtc_tm_to_ktime(struct rtc_time tm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) return ktime_set(rtc_tm_to_time64(&tm), 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) EXPORT_SYMBOL_GPL(rtc_tm_to_ktime);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) * Convert ktime to rtc_time
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) struct rtc_time rtc_ktime_to_tm(ktime_t kt)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) struct timespec64 ts;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) struct rtc_time ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) ts = ktime_to_timespec64(kt);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) /* Round up any ns */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) if (ts.tv_nsec)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) ts.tv_sec++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) rtc_time64_to_tm(ts.tv_sec, &ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) EXPORT_SYMBOL_GPL(rtc_ktime_to_tm);
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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