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-rw-r--r--drivers/rtc/date.c71
1 files changed, 32 insertions, 39 deletions
diff --git a/drivers/rtc/date.c b/drivers/rtc/date.c
index 8c643a0b46..bfa2e1378e 100644
--- a/drivers/rtc/date.c
+++ b/drivers/rtc/date.c
@@ -5,10 +5,6 @@
* SPDX-License-Identifier: GPL-2.0+
*/
-/*
- * Date & Time support for Philips PCF8563 RTC
- */
-
#include <common.h>
#include <command.h>
#include <errno.h>
@@ -28,53 +24,52 @@ static int month_days[12] = {
31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};
+static int month_offset[] = {
+ 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
+};
+
/*
* This only works for the Gregorian calendar - i.e. after 1752 (in the UK)
*/
int rtc_calc_weekday(struct rtc_time *tm)
{
- int leapsToDate;
- int lastYear;
+ int leaps_to_date;
+ int last_year;
int day;
- int MonthOffset[] = { 0,31,59,90,120,151,181,212,243,273,304,334 };
if (tm->tm_year < 1753)
- return -EINVAL;
- lastYear=tm->tm_year-1;
+ return -1;
+ last_year = tm->tm_year - 1;
- /*
- * Number of leap corrections to apply up to end of last year
- */
- leapsToDate = lastYear/4 - lastYear/100 + lastYear/400;
+ /* Number of leap corrections to apply up to end of last year */
+ leaps_to_date = last_year / 4 - last_year / 100 + last_year / 400;
/*
* This year is a leap year if it is divisible by 4 except when it is
* divisible by 100 unless it is divisible by 400
*
- * e.g. 1904 was a leap year, 1900 was not, 1996 is, and 2000 will be
+ * e.g. 1904 was a leap year, 1900 was not, 1996 is, and 2000 is.
*/
- if((tm->tm_year%4==0) &&
- ((tm->tm_year%100!=0) || (tm->tm_year%400==0)) &&
- (tm->tm_mon>2)) {
- /*
- * We are past Feb. 29 in a leap year
- */
- day=1;
+ if (tm->tm_year % 4 == 0 &&
+ ((tm->tm_year % 100 != 0) || (tm->tm_year % 400 == 0)) &&
+ tm->tm_mon > 2) {
+ /* We are past Feb. 29 in a leap year */
+ day = 1;
} else {
- day=0;
+ day = 0;
}
- day += lastYear*365 + leapsToDate + MonthOffset[tm->tm_mon-1] + tm->tm_mday;
-
- tm->tm_wday=day%7;
+ day += last_year * 365 + leaps_to_date + month_offset[tm->tm_mon - 1] +
+ tm->tm_mday;
+ tm->tm_wday = day % 7;
return 0;
}
int rtc_to_tm(int tim, struct rtc_time *tm)
{
- register int i;
- register long hms, day;
+ register int i;
+ register long hms, day;
day = tim / SECDAY;
hms = tim % SECDAY;
@@ -85,22 +80,19 @@ int rtc_to_tm(int tim, struct rtc_time *tm)
tm->tm_sec = (hms % 3600) % 60;
/* Number of years in days */
- for (i = STARTOFTIME; day >= days_in_year(i); i++) {
+ for (i = STARTOFTIME; day >= days_in_year(i); i++)
day -= days_in_year(i);
- }
tm->tm_year = i;
/* Number of months in days left */
- if (leapyear(tm->tm_year)) {
+ if (leapyear(tm->tm_year))
days_in_month(FEBRUARY) = 29;
- }
- for (i = 1; day >= days_in_month(i); i++) {
+ for (i = 1; day >= days_in_month(i); i++)
day -= days_in_month(i);
- }
days_in_month(FEBRUARY) = 28;
tm->tm_mon = i;
- /* Days are what is left over (+1) from all that. */
+ /* Days are what is left over (+1) from all that */
tm->tm_mday = day + 1;
/* Zero unused fields */
@@ -113,19 +105,20 @@ int rtc_to_tm(int tim, struct rtc_time *tm)
return rtc_calc_weekday(tm);
}
-/* Converts Gregorian date to seconds since 1970-01-01 00:00:00.
+/*
+ * Converts Gregorian date to seconds since 1970-01-01 00:00:00.
* Assumes input in normal date format, i.e. 1980-12-31 23:59:59
* => year=1980, mon=12, day=31, hour=23, min=59, sec=59.
*
* [For the Julian calendar (which was used in Russia before 1917,
* Britain & colonies before 1752, anywhere else before 1582,
* and is still in use by some communities) leave out the
- * -year/100+year/400 terms, and add 10.]
+ * -year / 100 + year / 400 terms, and add 10.]
*
* This algorithm was first published by Gauss (I think).
*
* WARNING: this function will overflow on 2106-02-07 06:28:16 on
- * machines were long is 32-bit! (However, as time_t is signed, we
+ * machines where long is 32-bit! (However, as time_t is signed, we
* will already get problems at other places on 2038-01-19 03:14:08)
*/
unsigned long rtc_mktime(const struct rtc_time *tm)
@@ -135,8 +128,8 @@ unsigned long rtc_mktime(const struct rtc_time *tm)
int days, hours;
mon -= 2;
- if (0 >= (int)mon) { /* 1..12 -> 11,12,1..10 */
- mon += 12; /* Puts Feb last since it has leap day */
+ if (0 >= (int)mon) { /* 1..12 -> 11, 12, 1..10 */
+ mon += 12; /* Puts Feb last since it has leap day */
year -= 1;
}