forked from Minki/linux
87ebfd6439
The Kconfig currently controlling compilation of this code is: drivers/rtc/Kconfig:config RTC_LIB drivers/rtc/Kconfig: bool ...meaning that it currently is not being built as a module by anyone. Lets remove the couple traces of modular infrastructure use, so that when reading the driver there is no doubt it is builtin-only. We delete the MODULE_LICENSE tag since all that information is already contained at the top of the file in the comments. We don't replace module.h with init.h since the file doesn't need that. However we do add export.h since the file uses EXPORT_SYMBOL. Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: rtc-linux@googlegroups.com Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
151 lines
3.4 KiB
C
151 lines
3.4 KiB
C
/*
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* rtc and date/time utility functions
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*
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* Copyright (C) 2005-06 Tower Technologies
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* Author: Alessandro Zummo <a.zummo@towertech.it>
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*
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* based on arch/arm/common/rtctime.c and other bits
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/export.h>
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#include <linux/rtc.h>
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static const unsigned char rtc_days_in_month[] = {
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31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
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};
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static const unsigned short rtc_ydays[2][13] = {
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/* Normal years */
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{ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
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/* Leap years */
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{ 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
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};
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#define LEAPS_THRU_END_OF(y) ((y)/4 - (y)/100 + (y)/400)
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/*
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* The number of days in the month.
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*/
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int rtc_month_days(unsigned int month, unsigned int year)
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{
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return rtc_days_in_month[month] + (is_leap_year(year) && month == 1);
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}
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EXPORT_SYMBOL(rtc_month_days);
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/*
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* The number of days since January 1. (0 to 365)
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*/
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int rtc_year_days(unsigned int day, unsigned int month, unsigned int year)
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{
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return rtc_ydays[is_leap_year(year)][month] + day-1;
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}
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EXPORT_SYMBOL(rtc_year_days);
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/*
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* rtc_time_to_tm64 - Converts time64_t to rtc_time.
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* Convert seconds since 01-01-1970 00:00:00 to Gregorian date.
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*/
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void rtc_time64_to_tm(time64_t time, struct rtc_time *tm)
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{
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unsigned int month, year;
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unsigned long secs;
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int days;
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/* time must be positive */
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days = div_s64(time, 86400);
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secs = time - (unsigned int) days * 86400;
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/* day of the week, 1970-01-01 was a Thursday */
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tm->tm_wday = (days + 4) % 7;
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year = 1970 + days / 365;
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days -= (year - 1970) * 365
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+ LEAPS_THRU_END_OF(year - 1)
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- LEAPS_THRU_END_OF(1970 - 1);
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if (days < 0) {
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year -= 1;
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days += 365 + is_leap_year(year);
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}
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tm->tm_year = year - 1900;
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tm->tm_yday = days + 1;
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for (month = 0; month < 11; month++) {
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int newdays;
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newdays = days - rtc_month_days(month, year);
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if (newdays < 0)
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break;
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days = newdays;
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}
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tm->tm_mon = month;
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tm->tm_mday = days + 1;
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tm->tm_hour = secs / 3600;
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secs -= tm->tm_hour * 3600;
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tm->tm_min = secs / 60;
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tm->tm_sec = secs - tm->tm_min * 60;
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tm->tm_isdst = 0;
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}
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EXPORT_SYMBOL(rtc_time64_to_tm);
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/*
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* Does the rtc_time represent a valid date/time?
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*/
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int rtc_valid_tm(struct rtc_time *tm)
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{
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if (tm->tm_year < 70
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|| ((unsigned)tm->tm_mon) >= 12
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|| tm->tm_mday < 1
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|| tm->tm_mday > rtc_month_days(tm->tm_mon, tm->tm_year + 1900)
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|| ((unsigned)tm->tm_hour) >= 24
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|| ((unsigned)tm->tm_min) >= 60
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|| ((unsigned)tm->tm_sec) >= 60)
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return -EINVAL;
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return 0;
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}
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EXPORT_SYMBOL(rtc_valid_tm);
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/*
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* rtc_tm_to_time64 - Converts rtc_time to time64_t.
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* Convert Gregorian date to seconds since 01-01-1970 00:00:00.
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*/
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time64_t rtc_tm_to_time64(struct rtc_time *tm)
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{
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return mktime64(tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday,
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tm->tm_hour, tm->tm_min, tm->tm_sec);
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}
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EXPORT_SYMBOL(rtc_tm_to_time64);
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/*
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* Convert rtc_time to ktime
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*/
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ktime_t rtc_tm_to_ktime(struct rtc_time tm)
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{
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return ktime_set(rtc_tm_to_time64(&tm), 0);
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}
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EXPORT_SYMBOL_GPL(rtc_tm_to_ktime);
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/*
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* Convert ktime to rtc_time
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*/
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struct rtc_time rtc_ktime_to_tm(ktime_t kt)
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{
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struct timespec64 ts;
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struct rtc_time ret;
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ts = ktime_to_timespec64(kt);
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/* Round up any ns */
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if (ts.tv_nsec)
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ts.tv_sec++;
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rtc_time64_to_tm(ts.tv_sec, &ret);
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return ret;
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}
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EXPORT_SYMBOL_GPL(rtc_ktime_to_tm);
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