diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c index 6f47d68d2c86..7c006c2b125f 100644 --- a/drivers/rtc/rtc-cmos.c +++ b/drivers/rtc/rtc-cmos.c @@ -470,10 +470,57 @@ static int cmos_validate_alarm(struct device *dev, struct rtc_wkalrm *t) return 0; } +struct cmos_set_alarm_callback_param { + struct cmos_rtc *cmos; + unsigned char mon, mday, hrs, min, sec; + struct rtc_wkalrm *t; +}; + +/* Note: this function may be executed by mc146818_avoid_UIP() more then + * once + */ +static void cmos_set_alarm_callback(unsigned char __always_unused seconds, + void *param_in) +{ + struct cmos_set_alarm_callback_param *p = + (struct cmos_set_alarm_callback_param *)param_in; + + /* next rtc irq must not be from previous alarm setting */ + cmos_irq_disable(p->cmos, RTC_AIE); + + /* update alarm */ + CMOS_WRITE(p->hrs, RTC_HOURS_ALARM); + CMOS_WRITE(p->min, RTC_MINUTES_ALARM); + CMOS_WRITE(p->sec, RTC_SECONDS_ALARM); + + /* the system may support an "enhanced" alarm */ + if (p->cmos->day_alrm) { + CMOS_WRITE(p->mday, p->cmos->day_alrm); + if (p->cmos->mon_alrm) + CMOS_WRITE(p->mon, p->cmos->mon_alrm); + } + + if (use_hpet_alarm()) { + /* + * FIXME the HPET alarm glue currently ignores day_alrm + * and mon_alrm ... + */ + hpet_set_alarm_time(p->t->time.tm_hour, p->t->time.tm_min, + p->t->time.tm_sec); + } + + if (p->t->enabled) + cmos_irq_enable(p->cmos, RTC_AIE); +} + static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t) { struct cmos_rtc *cmos = dev_get_drvdata(dev); - unsigned char mon, mday, hrs, min, sec, rtc_control; + struct cmos_set_alarm_callback_param p = { + .cmos = cmos, + .t = t + }; + unsigned char rtc_control; int ret; /* This not only a rtc_op, but also called directly */ @@ -484,11 +531,11 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t) if (ret < 0) return ret; - mon = t->time.tm_mon + 1; - mday = t->time.tm_mday; - hrs = t->time.tm_hour; - min = t->time.tm_min; - sec = t->time.tm_sec; + p.mon = t->time.tm_mon + 1; + p.mday = t->time.tm_mday; + p.hrs = t->time.tm_hour; + p.min = t->time.tm_min; + p.sec = t->time.tm_sec; spin_lock_irq(&rtc_lock); rtc_control = CMOS_READ(RTC_CONTROL); @@ -496,43 +543,21 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t) if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) { /* Writing 0xff means "don't care" or "match all". */ - mon = (mon <= 12) ? bin2bcd(mon) : 0xff; - mday = (mday >= 1 && mday <= 31) ? bin2bcd(mday) : 0xff; - hrs = (hrs < 24) ? bin2bcd(hrs) : 0xff; - min = (min < 60) ? bin2bcd(min) : 0xff; - sec = (sec < 60) ? bin2bcd(sec) : 0xff; + p.mon = (p.mon <= 12) ? bin2bcd(p.mon) : 0xff; + p.mday = (p.mday >= 1 && p.mday <= 31) ? bin2bcd(p.mday) : 0xff; + p.hrs = (p.hrs < 24) ? bin2bcd(p.hrs) : 0xff; + p.min = (p.min < 60) ? bin2bcd(p.min) : 0xff; + p.sec = (p.sec < 60) ? bin2bcd(p.sec) : 0xff; } - spin_lock_irq(&rtc_lock); - - /* next rtc irq must not be from previous alarm setting */ - cmos_irq_disable(cmos, RTC_AIE); - - /* update alarm */ - CMOS_WRITE(hrs, RTC_HOURS_ALARM); - CMOS_WRITE(min, RTC_MINUTES_ALARM); - CMOS_WRITE(sec, RTC_SECONDS_ALARM); - - /* the system may support an "enhanced" alarm */ - if (cmos->day_alrm) { - CMOS_WRITE(mday, cmos->day_alrm); - if (cmos->mon_alrm) - CMOS_WRITE(mon, cmos->mon_alrm); - } - - if (use_hpet_alarm()) { - /* - * FIXME the HPET alarm glue currently ignores day_alrm - * and mon_alrm ... - */ - hpet_set_alarm_time(t->time.tm_hour, t->time.tm_min, - t->time.tm_sec); - } - - if (t->enabled) - cmos_irq_enable(cmos, RTC_AIE); - - spin_unlock_irq(&rtc_lock); + /* + * Some Intel chipsets disconnect the alarm registers when the clock + * update is in progress - during this time writes fail silently. + * + * Use mc146818_avoid_UIP() to avoid this. + */ + if (!mc146818_avoid_UIP(cmos_set_alarm_callback, &p)) + return -EIO; cmos->alarm_expires = rtc_tm_to_time64(&t->time);