/*
* Decode time/date into rtc_time structure
*/
static void at91_rtc_decodetime(unsigned int timereg, unsigned int calreg,
struct rtc_time *tm)
{
unsigned int time, date;
/* must read twice in case it changes */
do {
time = at91_rtc_read(timereg);
date = at91_rtc_read(calreg);
} while ((time != at91_rtc_read(timereg)) ||
(date != at91_rtc_read(calreg)));
tm->tm_sec = bcd2bin((time & AT91_RTC_SEC) >> 0);
tm->tm_min = bcd2bin((time & AT91_RTC_MIN) >> 8);
tm->tm_hour = bcd2bin((time & AT91_RTC_HOUR) >> 16);
/*
* The Calendar Alarm register does not have a field for
* the year - so these will return an invalid value. When an
* alarm is set, at91_alarm_year will store the current year.
*/
tm->tm_year = bcd2bin(date & AT91_RTC_CENT) * 100; /* century */
tm->tm_year += bcd2bin((date & AT91_RTC_YEAR) >> 8); /* year */
tm->tm_wday = bcd2bin((date & AT91_RTC_DAY) >> 21) - 1; /* day of the week [0-6], Sunday=0 */
tm->tm_mon = bcd2bin((date & AT91_RTC_MONTH) >> 16) - 1;
tm->tm_mday = bcd2bin((date & AT91_RTC_DATE) >> 24);
}
/*
* Set current time and date in RTC
*/
static int at91_rtc_settime(struct device *dev, struct rtc_time *tm)
{
unsigned long cr;
dev_dbg(dev, "%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
tm->tm_hour, tm->tm_min, tm->tm_sec);
/* Stop Time/Calendar from counting */
cr = at91_rtc_read(AT91_RTC_CR);
at91_rtc_write(AT91_RTC_CR, cr | AT91_RTC_UPDCAL | AT91_RTC_UPDTIM);
at91_rtc_write_ier(AT91_RTC_ACKUPD);
wait_for_completion(&at91_rtc_updated); /* wait for ACKUPD interrupt */
at91_rtc_write_idr(AT91_RTC_ACKUPD);
at91_rtc_write(AT91_RTC_TIMR,
bin2bcd(tm->tm_sec) << 0
| bin2bcd(tm->tm_min) << 8
| bin2bcd(tm->tm_hour) << 16);
at91_rtc_write(AT91_RTC_CALR,
bin2bcd((tm->tm_year + 1900) / 100) /* century */
| bin2bcd(tm->tm_year % 100) << 8 /* year */
| bin2bcd(tm->tm_mon + 1) << 16 /* tm_mon starts at zero */
| bin2bcd(tm->tm_wday + 1) << 21 /* day of the week [0-6], Sunday=0 */
| bin2bcd(tm->tm_mday) << 24);
/* Restart Time/Calendar */
cr = at91_rtc_read(AT91_RTC_CR);
at91_rtc_write(AT91_RTC_CR, cr & ~(AT91_RTC_UPDCAL | AT91_RTC_UPDTIM));
return 0;
}
/*
* IRQ handler for the RTC
*/
static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
{
struct platform_device *pdev = dev_id;
struct rtc_device *rtc = platform_get_drvdata(pdev);
unsigned int rtsr;
unsigned long events = 0;
rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read(AT91_RTC_IMR);
if (rtsr) { /* this interrupt is shared! Is it ours? */
if (rtsr & AT91_RTC_ALARM)
events |= (RTC_AF | RTC_IRQF);
if (rtsr & AT91_RTC_SECEV)
events |= (RTC_UF | RTC_IRQF);
if (rtsr & AT91_RTC_ACKUPD)
complete(&at91_rtc_updated);
at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
rtc_update_irq(rtc, 1, events);
pr_debug("%s(): num=%ld, events=0x%02lx\n", __func__,
events >> 8, events & 0x000000FF);
return IRQ_HANDLED;
}
return IRQ_NONE; /* not handled */
}
/*
* IRQ handler for the RTC
*/
static irqreturn_t at91_rtc_interrupt(int irq, void *dev_id)
{
struct platform_device *pdev = dev_id;
struct rtc_device *rtc = platform_get_drvdata(pdev);
unsigned int rtsr;
unsigned long events = 0;
int ret = IRQ_NONE;
spin_lock(&suspended_lock);
rtsr = at91_rtc_read(AT91_RTC_SR) & at91_rtc_read_imr();
if (rtsr) { /* this interrupt is shared! Is it ours? */
if (rtsr & AT91_RTC_ALARM)
events |= (RTC_AF | RTC_IRQF);
if (rtsr & AT91_RTC_SECEV) {
complete(&at91_rtc_upd_rdy);
at91_rtc_write_idr(AT91_RTC_SECEV);
}
if (rtsr & AT91_RTC_ACKUPD)
complete(&at91_rtc_updated);
at91_rtc_write(AT91_RTC_SCCR, rtsr); /* clear status reg */
if (!suspended) {
rtc_update_irq(rtc, 1, events);
dev_dbg(&pdev->dev, "%s(): num=%ld, events=0x%02lx\n",
__func__, events >> 8, events & 0x000000FF);
} else {
/*
* Provide additional RTC information in /proc/driver/rtc
*/
static int at91_rtc_proc(struct device *dev, struct seq_file *seq)
{
unsigned long imr = at91_rtc_read(AT91_RTC_IMR);
seq_printf(seq, "update_IRQ\t: %s\n",
(imr & AT91_RTC_ACKUPD) ? "yes" : "no");
seq_printf(seq, "periodic_IRQ\t: %s\n",
(imr & AT91_RTC_SECEV) ? "yes" : "no");
return 0;
}
static u32 at91_rtc_read_imr(void)
{
unsigned long flags;
u32 mask;
if (at91_rtc_config->use_shadow_imr) {
spin_lock_irqsave(&at91_rtc_lock, flags);
mask = at91_rtc_shadow_imr;
spin_unlock_irqrestore(&at91_rtc_lock, flags);
} else {
mask = at91_rtc_read(AT91_RTC_IMR);
}
return mask;
}
static int at91_rtc_suspend(struct device *dev)
{
/* this IRQ is shared with DBGU and other hardware which isn't
* necessarily doing PM like we are...
*/
at91_rtc_imr = at91_rtc_read(AT91_RTC_IMR)
& (AT91_RTC_ALARM|AT91_RTC_SECEV);
if (at91_rtc_imr) {
if (device_may_wakeup(dev))
enable_irq_wake(irq);
else
at91_rtc_write(AT91_RTC_IDR, at91_rtc_imr);
}
return 0;
}
/*
* Read alarm time and date in RTC
*/
static int at91_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct rtc_time *tm = &alrm->time;
at91_rtc_decodetime(AT91_RTC_TIMALR, AT91_RTC_CALALR, tm);
tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
tm->tm_year = at91_alarm_year - 1900;
alrm->enabled = (at91_rtc_read(AT91_RTC_IMR) & AT91_RTC_ALARM)
? 1 : 0;
pr_debug("%s(): %4d-%02d-%02d %02d:%02d:%02d\n", __func__,
1900 + tm->tm_year, tm->tm_mon, tm->tm_mday,
tm->tm_hour, tm->tm_min, tm->tm_sec);
return 0;
}
static void at91_rtc_write_idr(u32 mask)
{
unsigned long flags;
spin_lock_irqsave(&at91_rtc_lock, flags);
at91_rtc_write(AT91_RTC_IDR, mask);
/*
* Register read back (of any RTC-register) needed to make sure
* IDR-register write has reached the peripheral before updating
* shadow mask.
*
* Note that there is still a possibility that the mask is updated
* before interrupts have actually been disabled in hardware. The only
* way to be certain would be to poll the IMR-register, which is is
* the very register we are trying to emulate. The register read back
* is a reasonable heuristic.
*/
at91_rtc_read(AT91_RTC_SR);
at91_rtc_shadow_imr &= ~mask;
spin_unlock_irqrestore(&at91_rtc_lock, flags);
}
