/* * 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); }