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path: root/drivers/rtc/interface.c
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Diffstat (limited to 'drivers/rtc/interface.c')
-rw-r--r--drivers/rtc/interface.c117
1 files changed, 75 insertions, 42 deletions
diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c
index 794a4f036b99..b8b298efd9a9 100644
--- a/drivers/rtc/interface.c
+++ b/drivers/rtc/interface.c
@@ -186,7 +186,7 @@ static int rtc_read_alarm_internal(struct rtc_device *rtc,
if (!rtc->ops) {
err = -ENODEV;
- } else if (!rtc->ops->read_alarm) {
+ } else if (!test_bit(RTC_FEATURE_ALARM, rtc->features) || !rtc->ops->read_alarm) {
err = -EINVAL;
} else {
alarm->enabled = 0;
@@ -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 (!rtc->ops->read_alarm) {
+ } else if (!test_bit(RTC_FEATURE_ALARM, rtc->features)) {
err = -EINVAL;
} else {
memset(alarm, 0, sizeof(struct rtc_wkalrm));
@@ -423,6 +424,7 @@ static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
if (err)
return err;
now = rtc_tm_to_time64(&tm);
+
if (scheduled <= now)
return -ETIME;
/*
@@ -436,22 +438,46 @@ static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
if (!rtc->ops)
err = -ENODEV;
- else if (!rtc->ops->set_alarm)
+ else if (!test_bit(RTC_FEATURE_ALARM, rtc->features))
err = -EINVAL;
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;
}
int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
{
+ ktime_t alarm_time;
int err;
if (!rtc->ops)
return -ENODEV;
- else if (!rtc->ops->set_alarm)
+ else if (!test_bit(RTC_FEATURE_ALARM, rtc->features))
return -EINVAL;
err = rtc_valid_tm(&alarm->time);
@@ -468,7 +494,15 @@ int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
if (rtc->aie_timer.enabled)
rtc_timer_remove(rtc, &rtc->aie_timer);
- rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time);
+ alarm_time = rtc_tm_to_ktime(alarm->time);
+ /*
+ * Round down so we never miss a deadline, checking for past deadline is
+ * done in __rtc_set_alarm
+ */
+ if (test_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->features))
+ alarm_time = ktime_sub_ns(alarm_time, (u64)alarm->time.tm_sec * NSEC_PER_SEC);
+
+ rtc->aie_timer.node.expires = alarm_time;
rtc->aie_timer.period = 0;
if (alarm->enabled)
err = rtc_timer_enqueue(rtc, &rtc->aie_timer);
@@ -531,7 +565,7 @@ int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled)
/* nothing */;
else if (!rtc->ops)
err = -ENODEV;
- else if (!rtc->ops->alarm_irq_enable)
+ else if (!test_bit(RTC_FEATURE_ALARM, rtc->features) || !rtc->ops->alarm_irq_enable)
err = -EINVAL;
else
err = rtc->ops->alarm_irq_enable(rtc->dev.parent, enabled);
@@ -545,7 +579,7 @@ EXPORT_SYMBOL_GPL(rtc_alarm_irq_enable);
int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled)
{
- int rc = 0, err;
+ int err;
err = mutex_lock_interruptible(&rtc->ops_lock);
if (err)
@@ -561,23 +595,32 @@ int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled)
if (rtc->uie_rtctimer.enabled == enabled)
goto out;
- if (rtc->uie_unsupported) {
- err = -EINVAL;
- goto out;
+ if (!test_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->features) ||
+ !test_bit(RTC_FEATURE_ALARM, rtc->features)) {
+ mutex_unlock(&rtc->ops_lock);
+#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
+ return rtc_dev_update_irq_enable_emul(rtc, enabled);
+#else
+ return -EINVAL;
+#endif
}
if (enabled) {
struct rtc_time tm;
ktime_t now, onesec;
- rc = __rtc_read_time(rtc, &tm);
- if (rc)
+ err = __rtc_read_time(rtc, &tm);
+ if (err)
goto out;
onesec = ktime_set(1, 0);
now = rtc_tm_to_ktime(tm);
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);
}
@@ -585,24 +628,6 @@ int rtc_update_irq_enable(struct rtc_device *rtc, unsigned int enabled)
out:
mutex_unlock(&rtc->ops_lock);
- /*
- * __rtc_read_time() failed, this probably means that the RTC time has
- * never been set or less probably there is a transient error on the
- * bus. In any case, avoid enabling emulation has this will fail when
- * reading the time too.
- */
- if (rc)
- return rc;
-
-#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
- /*
- * Enable emulation if the driver returned -EINVAL to signal that it has
- * been configured without interrupts or they are not available at the
- * moment.
- */
- if (err == -EINVAL)
- err = rtc_dev_update_irq_enable_emul(rtc, enabled);
-#endif
return err;
}
EXPORT_SYMBOL_GPL(rtc_update_irq_enable);
@@ -699,7 +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);
@@ -807,9 +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 */
@@ -823,7 +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;
@@ -843,7 +871,7 @@ static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer)
static void rtc_alarm_disable(struct rtc_device *rtc)
{
- if (!rtc->ops || !rtc->ops->alarm_irq_enable)
+ if (!rtc->ops || !test_bit(RTC_FEATURE_ALARM, rtc->features) || !rtc->ops->alarm_irq_enable)
return;
rtc->ops->alarm_irq_enable(rtc->dev.parent, false);
@@ -903,13 +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)
generated by cgit (git 2.34.1) at 2025-12-21 19:26:53 +0000