diff options
Diffstat (limited to 'drivers/rtc/interface.c')
| -rw-r--r-- | drivers/rtc/interface.c | 60 |
1 files changed, 48 insertions, 12 deletions
diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index d8e835798153..b8b298efd9a9 100644 --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -205,7 +205,7 @@ static int rtc_read_alarm_internal(struct rtc_device *rtc, mutex_unlock(&rtc->ops_lock); - trace_rtc_read_alarm(rtc_tm_to_time64(&alarm->time), err); + trace_rtc_read_alarm(err?0:rtc_tm_to_time64(&alarm->time), err); return err; } @@ -256,7 +256,7 @@ int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) * * This could all instead be done in the lower level driver, * but since more than one lower level RTC implementation needs it, - * then it's probably best best to do it here instead of there.. + * then it's probably best to do it here instead of there.. */ /* Get the "before" timestamp */ @@ -274,10 +274,9 @@ int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) return err; /* full-function RTCs won't have such missing fields */ - if (rtc_valid_tm(&alarm->time) == 0) { - rtc_add_offset(rtc, &alarm->time); - return 0; - } + err = rtc_valid_tm(&alarm->time); + if (!err) + goto done; /* get the "after" timestamp, to detect wrapped fields */ err = rtc_read_time(rtc, &now); @@ -376,9 +375,11 @@ int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) err = rtc_valid_tm(&alarm->time); done: - if (err) + if (err && alarm->enabled) dev_warn(&rtc->dev, "invalid alarm value: %ptR\n", &alarm->time); + else + rtc_add_offset(rtc, &alarm->time); return err; } @@ -392,7 +393,7 @@ int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) return err; if (!rtc->ops) { err = -ENODEV; - } else if (!test_bit(RTC_FEATURE_ALARM, rtc->features) || !rtc->ops->read_alarm) { + } else if (!test_bit(RTC_FEATURE_ALARM, rtc->features)) { err = -EINVAL; } else { memset(alarm, 0, sizeof(struct rtc_wkalrm)); @@ -442,6 +443,29 @@ static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm) else err = rtc->ops->set_alarm(rtc->dev.parent, alarm); + /* + * Check for potential race described above. If the waiting for next + * second, and the second just ticked since the check above, either + * + * 1) It ticked after the alarm was set, and an alarm irq should be + * generated. + * + * 2) It ticked before the alarm was set, and alarm irq most likely will + * not be generated. + * + * While we cannot easily check for which of these two scenarios we + * are in, we can return -ETIME to signal that the timer has already + * expired, which is true in both cases. + */ + if ((scheduled - now) <= 1) { + err = __rtc_read_time(rtc, &tm); + if (err) + return err; + now = rtc_tm_to_time64(&tm); + if (scheduled <= now) + return -ETIME; + } + trace_rtc_set_alarm(rtc_tm_to_time64(&alarm->time), err); return err; } @@ -593,6 +617,10 @@ int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled) rtc->uie_rtctimer.node.expires = ktime_add(now, onesec); rtc->uie_rtctimer.period = ktime_set(1, 0); err = rtc_timer_enqueue(rtc, &rtc->uie_rtctimer); + if (!err && rtc->ops && rtc->ops->alarm_irq_enable) + err = rtc->ops->alarm_irq_enable(rtc->dev.parent, 1); + if (err) + goto out; } else { rtc_timer_remove(rtc, &rtc->uie_rtctimer); } @@ -696,7 +724,7 @@ struct rtc_device *rtc_class_open(const char *name) struct device *dev; struct rtc_device *rtc = NULL; - dev = class_find_device_by_name(rtc_class, name); + dev = class_find_device_by_name(&rtc_class, name); if (dev) rtc = to_rtc_device(dev); @@ -804,9 +832,13 @@ static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer) struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue); struct rtc_time tm; ktime_t now; + int err; + + err = __rtc_read_time(rtc, &tm); + if (err) + return err; timer->enabled = 1; - __rtc_read_time(rtc, &tm); now = rtc_tm_to_ktime(tm); /* Skip over expired timers */ @@ -820,7 +852,6 @@ static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer) trace_rtc_timer_enqueue(timer); if (!next || ktime_before(timer->node.expires, next->expires)) { struct rtc_wkalrm alarm; - int err; alarm.time = rtc_ktime_to_tm(timer->node.expires); alarm.enabled = 1; @@ -900,13 +931,18 @@ void rtc_timer_do_work(struct work_struct *work) struct timerqueue_node *next; ktime_t now; struct rtc_time tm; + int err; struct rtc_device *rtc = container_of(work, struct rtc_device, irqwork); mutex_lock(&rtc->ops_lock); again: - __rtc_read_time(rtc, &tm); + err = __rtc_read_time(rtc, &tm); + if (err) { + mutex_unlock(&rtc->ops_lock); + return; + } now = rtc_tm_to_ktime(tm); while ((next = timerqueue_getnext(&rtc->timerqueue))) { if (next->expires > now) |