int maple_set_rtc_time(struct rtc_time *tm)
{
unsigned char save_control, save_freq_select;
int sec, min, hour, mon, mday, year;
spin_lock(&rtc_lock);
save_control = maple_clock_read(RTC_CONTROL); /* tell the clock it's being set */
maple_clock_write((save_control|RTC_SET), RTC_CONTROL);
save_freq_select = maple_clock_read(RTC_FREQ_SELECT); /* stop and reset prescaler */
maple_clock_write((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);
sec = tm->tm_sec;
min = tm->tm_min;
hour = tm->tm_hour;
mon = tm->tm_mon;
mday = tm->tm_mday;
year = tm->tm_year;
if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
BIN_TO_BCD(sec);
BIN_TO_BCD(min);
BIN_TO_BCD(hour);
BIN_TO_BCD(mon);
BIN_TO_BCD(mday);
BIN_TO_BCD(year);
}
maple_clock_write(sec, RTC_SECONDS);
maple_clock_write(min, RTC_MINUTES);
maple_clock_write(hour, RTC_HOURS);
maple_clock_write(mon, RTC_MONTH);
maple_clock_write(mday, RTC_DAY_OF_MONTH);
maple_clock_write(year, RTC_YEAR);
/* The following flags have to be released exactly in this order,
* otherwise the DS12887 (popular MC146818A clone with integrated
* battery and quartz) will not reset the oscillator and will not
* update precisely 500 ms later. You won't find this mentioned in
* the Dallas Semiconductor data sheets, but who believes data
* sheets anyway ... -- Markus Kuhn
*/
maple_clock_write(save_control, RTC_CONTROL);
maple_clock_write(save_freq_select, RTC_FREQ_SELECT);
spin_unlock(&rtc_lock);
return 0;
}
void maple_get_rtc_time(struct rtc_time *tm)
{
do {
tm->tm_sec = maple_clock_read(RTC_SECONDS);
tm->tm_min = maple_clock_read(RTC_MINUTES);
tm->tm_hour = maple_clock_read(RTC_HOURS);
tm->tm_mday = maple_clock_read(RTC_DAY_OF_MONTH);
tm->tm_mon = maple_clock_read(RTC_MONTH);
tm->tm_year = maple_clock_read(RTC_YEAR);
} while (tm->tm_sec != maple_clock_read(RTC_SECONDS));
if (!(maple_clock_read(RTC_CONTROL) & RTC_DM_BINARY)
|| RTC_ALWAYS_BCD) {
tm->tm_sec = bcd2bin(tm->tm_sec);
tm->tm_min = bcd2bin(tm->tm_min);
tm->tm_hour = bcd2bin(tm->tm_hour);
tm->tm_mday = bcd2bin(tm->tm_mday);
tm->tm_mon = bcd2bin(tm->tm_mon);
tm->tm_year = bcd2bin(tm->tm_year);
}
if ((tm->tm_year + 1900) < 1970)
tm->tm_year += 100;
GregorianDay(tm);
}
int maple_set_rtc_time(struct rtc_time *tm)
{
unsigned char save_control, save_freq_select;
int sec, min, hour, mon, mday, year;
spin_lock(&rtc_lock);
save_control = maple_clock_read(RTC_CONTROL);
maple_clock_write((save_control|RTC_SET), RTC_CONTROL);
save_freq_select = maple_clock_read(RTC_FREQ_SELECT);
maple_clock_write((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);
sec = tm->tm_sec;
min = tm->tm_min;
hour = tm->tm_hour;
mon = tm->tm_mon;
mday = tm->tm_mday;
year = tm->tm_year;
if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
sec = bin2bcd(sec);
min = bin2bcd(min);
hour = bin2bcd(hour);
mon = bin2bcd(mon);
mday = bin2bcd(mday);
year = bin2bcd(year);
}
maple_clock_write(sec, RTC_SECONDS);
maple_clock_write(min, RTC_MINUTES);
maple_clock_write(hour, RTC_HOURS);
maple_clock_write(mon, RTC_MONTH);
maple_clock_write(mday, RTC_DAY_OF_MONTH);
maple_clock_write(year, RTC_YEAR);
maple_clock_write(save_control, RTC_CONTROL);
maple_clock_write(save_freq_select, RTC_FREQ_SELECT);
spin_unlock(&rtc_lock);
return 0;
}
void maple_get_rtc_time(struct rtc_time *tm)
{
int uip, i;
/* The Linux interpretation of the CMOS clock register contents:
* When the Update-In-Progress (UIP) flag goes from 1 to 0, the
* RTC registers show the second which has precisely just started.
* Let's hope other operating systems interpret the RTC the same way.
*/
/* Since the UIP flag is set for about 2.2 ms and the clock
* is typically written with a precision of 1 jiffy, trying
* to obtain a precision better than a few milliseconds is
* an illusion. Only consistency is interesting, this also
* allows to use the routine for /dev/rtc without a potential
* 1 second kernel busy loop triggered by any reader of /dev/rtc.
*/
for (i = 0; i<1000000; i++) {
uip = maple_clock_read(RTC_FREQ_SELECT);
tm->tm_sec = maple_clock_read(RTC_SECONDS);
tm->tm_min = maple_clock_read(RTC_MINUTES);
tm->tm_hour = maple_clock_read(RTC_HOURS);
tm->tm_mday = maple_clock_read(RTC_DAY_OF_MONTH);
tm->tm_mon = maple_clock_read(RTC_MONTH);
tm->tm_year = maple_clock_read(RTC_YEAR);
uip |= maple_clock_read(RTC_FREQ_SELECT);
if ((uip & RTC_UIP)==0)
break;
}
if (!(maple_clock_read(RTC_CONTROL) & RTC_DM_BINARY)
|| RTC_ALWAYS_BCD) {
BCD_TO_BIN(tm->tm_sec);
BCD_TO_BIN(tm->tm_min);
BCD_TO_BIN(tm->tm_hour);
BCD_TO_BIN(tm->tm_mday);
BCD_TO_BIN(tm->tm_mon);
BCD_TO_BIN(tm->tm_year);
}
if ((tm->tm_year + 1900) < 1970)
tm->tm_year += 100;
GregorianDay(tm);
}
