1 files changed, 41 insertions, 65 deletions

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index f4ace1bf8382..0ddccdff119a 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -2,13 +2,13 @@
 /*
  * Alarmtimer interface
  *
- * This interface provides a timer which is similarto hrtimers,
+ * This interface provides a timer which is similar to hrtimers,
  * but triggers a RTC alarm if the box is suspend.
  *
  * This interface is influenced by the Android RTC Alarm timer
  * interface.
  *
- * Copyright (C) 2010 IBM Corperation
+ * Copyright (C) 2010 IBM Corporation
  *
  * Author: John Stultz <john.stultz@linaro.org>
  */
@@ -81,8 +81,7 @@ struct rtc_device *alarmtimer_get_rtcdev(void)
 }
 EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev);
 
-static int alarmtimer_rtc_add_device(struct device *dev,
-				struct class_interface *class_intf)
+static int alarmtimer_rtc_add_device(struct device *dev)
 {
 	unsigned long flags;
 	struct rtc_device *rtc = to_rtc_device(dev);
@@ -92,7 +91,7 @@ static int alarmtimer_rtc_add_device(struct device *dev,
 	if (rtcdev)
 		return -EBUSY;
 
-	if (!rtc->ops->set_alarm)
+	if (!test_bit(RTC_FEATURE_ALARM, rtc->features))
 		return -1;
 	if (!device_may_wakeup(rtc->dev.parent))
 		return -1;
@@ -135,7 +134,7 @@ static struct class_interface alarmtimer_rtc_interface = {
 
 static int alarmtimer_rtc_interface_setup(void)
 {
-	alarmtimer_rtc_interface.class = rtc_class;
+	alarmtimer_rtc_interface.class = &rtc_class;
 	return class_interface_register(&alarmtimer_rtc_interface);
 }
 static void alarmtimer_rtc_interface_remove(void)
@@ -198,28 +197,15 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
 {
 	struct alarm *alarm = container_of(timer, struct alarm, timer);
 	struct alarm_base *base = &alarm_bases[alarm->type];
-	unsigned long flags;
-	int ret = HRTIMER_NORESTART;
-	int restart = ALARMTIMER_NORESTART;
 
-	spin_lock_irqsave(&base->lock, flags);
-	alarmtimer_dequeue(base, alarm);
-	spin_unlock_irqrestore(&base->lock, flags);
+	scoped_guard (spinlock_irqsave, &base->lock)
+		alarmtimer_dequeue(base, alarm);
 
 	if (alarm->function)
-		restart = alarm->function(alarm, base->get_ktime());
-
-	spin_lock_irqsave(&base->lock, flags);
-	if (restart != ALARMTIMER_NORESTART) {
-		hrtimer_set_expires(&alarm->timer, alarm->node.expires);
-		alarmtimer_enqueue(base, alarm);
-		ret = HRTIMER_RESTART;
-	}
-	spin_unlock_irqrestore(&base->lock, flags);
+		alarm->function(alarm, base->get_ktime());
 
 	trace_alarmtimer_fired(alarm, base->get_ktime());
-	return ret;
-
+	return HRTIMER_NORESTART;
 }
 
 ktime_t alarm_expires_remaining(const struct alarm *alarm)
@@ -291,6 +277,17 @@ static int alarmtimer_suspend(struct device *dev)
 	rtc_timer_cancel(rtc, &rtctimer);
 	rtc_read_time(rtc, &tm);
 	now = rtc_tm_to_ktime(tm);
+
+	/*
+	 * If the RTC alarm timer only supports a limited time offset, set the
+	 * alarm time to the maximum supported value.
+	 * The system may wake up earlier (possibly much earlier) than expected
+	 * when the alarmtimer runs. This is the best the kernel can do if
+	 * the alarmtimer exceeds the time that the rtc device can be programmed
+	 * for.
+	 */
+	min = rtc_bound_alarmtime(rtc, min);
+
 	now = ktime_add(now, min);
 
 	/* Set alarm, if in the past reject suspend briefly to handle */
@@ -324,10 +321,9 @@ static int alarmtimer_resume(struct device *dev)
 
 static void
 __alarm_init(struct alarm *alarm, enum alarmtimer_type type,
-	     enum alarmtimer_restart (*function)(struct alarm *, ktime_t))
+	     void (*function)(struct alarm *, ktime_t))
 {
 	timerqueue_init(&alarm->node);
-	alarm->timer.function = alarmtimer_fired;
 	alarm->function = function;
 	alarm->type = type;
 	alarm->state = ALARMTIMER_STATE_INACTIVE;
@@ -340,10 +336,10 @@ __alarm_init(struct alarm *alarm, enum alarmtimer_type type,
  * @function: callback that is run when the alarm fires
  */
 void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
-		enum alarmtimer_restart (*function)(struct alarm *, ktime_t))
+		void (*function)(struct alarm *, ktime_t))
 {
-	hrtimer_init(&alarm->timer, alarm_bases[type].base_clockid,
-		     HRTIMER_MODE_ABS);
+	hrtimer_setup(&alarm->timer, alarmtimer_fired, alarm_bases[type].base_clockid,
+		      HRTIMER_MODE_ABS);
 	__alarm_init(alarm, type, function);
 }
 EXPORT_SYMBOL_GPL(alarm_init);
@@ -527,37 +523,18 @@ static enum alarmtimer_type clock2alarm(clockid_t clockid)
 /**
  * alarm_handle_timer - Callback for posix timers
  * @alarm: alarm that fired
+ * @now: time at the timer expiration
  *
  * Posix timer callback for expired alarm timers.
+ *
+ * Return: whether the timer is to be restarted
  */
-static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm,
-							ktime_t now)
+static void alarm_handle_timer(struct alarm *alarm, ktime_t now)
 {
-	struct k_itimer *ptr = container_of(alarm, struct k_itimer,
-					    it.alarm.alarmtimer);
-	enum alarmtimer_restart result = ALARMTIMER_NORESTART;
-	unsigned long flags;
-	int si_private = 0;
+	struct k_itimer *ptr = container_of(alarm, struct k_itimer, it.alarm.alarmtimer);
 
-	spin_lock_irqsave(&ptr->it_lock, flags);
-
-	ptr->it_active = 0;
-	if (ptr->it_interval)
-		si_private = ++ptr->it_requeue_pending;
-
-	if (posix_timer_event(ptr, si_private) && ptr->it_interval) {
-		/*
-		 * Handle ignored signals and rearm the timer. This will go
-		 * away once we handle ignored signals proper.
-		 */
-		ptr->it_overrun += alarm_forward_now(alarm, ptr->it_interval);
-		++ptr->it_requeue_pending;
-		ptr->it_active = 1;
-		result = ALARMTIMER_RESTART;
-	}
-	spin_unlock_irqrestore(&ptr->it_lock, flags);
-
-	return result;
+	guard(spinlock_irqsave)(&ptr->it_lock);
+	posix_timer_queue_signal(ptr);
 }
 
 /**
@@ -715,24 +692,24 @@ static int alarm_timer_create(struct k_itimer *new_timer)
 /**
  * alarmtimer_nsleep_wakeup - Wakeup function for alarm_timer_nsleep
  * @alarm: ptr to alarm that fired
+ * @now: time at the timer expiration
  *
  * Wakes up the task that set the alarmtimer
  */
-static enum alarmtimer_restart alarmtimer_nsleep_wakeup(struct alarm *alarm,
-								ktime_t now)
+static void alarmtimer_nsleep_wakeup(struct alarm *alarm, ktime_t now)
 {
-	struct task_struct *task = (struct task_struct *)alarm->data;
+	struct task_struct *task = alarm->data;
 
 	alarm->data = NULL;
 	if (task)
 		wake_up_process(task);
-	return ALARMTIMER_NORESTART;
 }
 
 /**
  * alarmtimer_do_nsleep - Internal alarmtimer nsleep implementation
  * @alarm: ptr to alarmtimer
  * @absexp: absolute expiration time
+ * @type: alarm type (BOOTTIME/REALTIME).
  *
  * Sets the alarm timer and sleeps until it is fired or interrupted.
  */
@@ -777,10 +754,10 @@ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp,
 
 static void
 alarm_init_on_stack(struct alarm *alarm, enum alarmtimer_type type,
-		    enum alarmtimer_restart (*function)(struct alarm *, ktime_t))
+		    void (*function)(struct alarm *, ktime_t))
 {
-	hrtimer_init_on_stack(&alarm->timer, alarm_bases[type].base_clockid,
-			      HRTIMER_MODE_ABS);
+	hrtimer_setup_on_stack(&alarm->timer, alarmtimer_fired, alarm_bases[type].base_clockid,
+			       HRTIMER_MODE_ABS);
 	__alarm_init(alarm, type, function);
 }
 
@@ -804,9 +781,8 @@ static long __sched alarm_timer_nsleep_restart(struct restart_block *restart)
 /**
  * alarm_timer_nsleep - alarmtimer nanosleep
  * @which_clock: clockid
- * @flags: determins abstime or relative
+ * @flags: determines abstime or relative
  * @tsreq: requested sleep time (abs or rel)
- * @rmtp: remaining sleep time saved
  *
  * Handles clock_nanosleep calls against _ALARM clockids
  */
@@ -817,7 +793,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
 	struct restart_block *restart = &current->restart_block;
 	struct alarm alarm;
 	ktime_t exp;
-	int ret = 0;
+	int ret;
 
 	if (!alarmtimer_get_rtcdev())
 		return -EOPNOTSUPP;
@@ -848,9 +824,9 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
 	if (flags == TIMER_ABSTIME)
 		return -ERESTARTNOHAND;
 
-	restart->fn = alarm_timer_nsleep_restart;
 	restart->nanosleep.clockid = type;
 	restart->nanosleep.expires = exp;
+	set_restart_fn(restart, alarm_timer_nsleep_restart);
 	return ret;
 }