int xicor_set_time(unsigned long t)
{
struct rtc_time tm;
int tmp;
unsigned long flags;
rtc_time_to_tm(t, &tm);
tm.tm_year += 1900;
spin_lock_irqsave(&rtc_lock, flags);
/* unlock writes to the CCR */
xicor_write(X1241REG_SR, X1241REG_SR_WEL);
xicor_write(X1241REG_SR, X1241REG_SR_WEL | X1241REG_SR_RWEL);
/* trivial ones */
tm.tm_sec = bin2bcd(tm.tm_sec);
xicor_write(X1241REG_SC, tm.tm_sec);
tm.tm_min = bin2bcd(tm.tm_min);
xicor_write(X1241REG_MN, tm.tm_min);
tm.tm_mday = bin2bcd(tm.tm_mday);
xicor_write(X1241REG_DT, tm.tm_mday);
/* tm_mon starts from 0, *ick* */
tm.tm_mon ++;
tm.tm_mon = bin2bcd(tm.tm_mon);
xicor_write(X1241REG_MO, tm.tm_mon);
/* year is split */
tmp = tm.tm_year / 100;
tm.tm_year %= 100;
xicor_write(X1241REG_YR, tm.tm_year);
xicor_write(X1241REG_Y2K, tmp);
/* hour is the most tricky one */
tmp = xicor_read(X1241REG_HR);
if (tmp & X1241REG_HR_MIL) {
/* 24 hour format */
tm.tm_hour = bin2bcd(tm.tm_hour);
tmp = (tmp & ~0x3f) | (tm.tm_hour & 0x3f);
} else {
/* 12 hour format, with 0x2 for pm */
tmp = tmp & ~0x3f;
if (tm.tm_hour >= 12) {
tmp |= 0x20;
tm.tm_hour -= 12;
}
tm.tm_hour = bin2bcd(tm.tm_hour);
tmp |= tm.tm_hour;
}
xicor_write(X1241REG_HR, tmp);
xicor_write(X1241REG_SR, 0);
spin_unlock_irqrestore(&rtc_lock, flags);
return 0;
}
/*
* 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.
*
* BUG: This routine does not handle hour overflow properly; it just
* sets the minutes. Usually you'll only notice that after reboot!
*/
int set_rtc_mmss(unsigned long nowtime)
{
int retval = 0;
int real_seconds, real_minutes, cmos_minutes;
cmos_minutes = xicor_read(X1241REG_MN);
BCD_TO_BIN(cmos_minutes);
/*
* since we're only adjusting minutes and seconds,
* don't interfere with hour overflow. This avoids
* messing with unknown time zones but requires your
* RTC not to be off by more than 15 minutes
*/
real_seconds = nowtime % 60;
real_minutes = nowtime / 60;
if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
real_minutes += 30; /* correct for half hour time zone */
real_minutes %= 60;
/* unlock writes to the CCR */
xicor_write(X1241REG_SR, X1241REG_SR_WEL);
xicor_write(X1241REG_SR, X1241REG_SR_WEL | X1241REG_SR_RWEL);
if (abs(real_minutes - cmos_minutes) < 30) {
BIN_TO_BCD(real_seconds);
BIN_TO_BCD(real_minutes);
xicor_write(X1241REG_SC, real_seconds);
xicor_write(X1241REG_MN, real_minutes);
} else {
printk(KERN_WARNING
"set_rtc_mmss: can't update from %d to %d\n",
cmos_minutes, real_minutes);
retval = -1;
}
xicor_write(X1241REG_SR, 0);
printk("set_rtc_mmss: %02d:%02d\n", real_minutes, real_seconds);
return retval;
}
