*/
#include <linux/rtc.h>
+#include <linux/sched.h>
+#include <linux/module.h>
#include <linux/log2.h>
+#include <linux/workqueue.h>
-int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm)
+static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer);
+static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer);
+
+static int __rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm)
{
int err;
-
- err = mutex_lock_interruptible(&rtc->ops_lock);
- if (err)
- return err;
-
if (!rtc->ops)
err = -ENODEV;
else if (!rtc->ops->read_time)
memset(tm, 0, sizeof(struct rtc_time));
err = rtc->ops->read_time(rtc->dev.parent, tm);
}
+ return err;
+}
+int rtc_read_time(struct rtc_device *rtc, struct rtc_time *tm)
+{
+ int err;
+
+ err = mutex_lock_interruptible(&rtc->ops_lock);
+ if (err)
+ return err;
+
+ err = __rtc_read_time(rtc, tm);
mutex_unlock(&rtc->ops_lock);
return err;
}
if (!rtc->ops)
err = -ENODEV;
- else if (!rtc->ops->set_time)
- err = -EINVAL;
- else
+ else if (rtc->ops->set_time)
err = rtc->ops->set_time(rtc->dev.parent, tm);
+ else if (rtc->ops->set_mmss) {
+ unsigned long secs;
+ err = rtc_tm_to_time(tm, &secs);
+ if (err == 0)
+ err = rtc->ops->set_mmss(rtc->dev.parent, secs);
+ } else
+ err = -EINVAL;
mutex_unlock(&rtc->ops_lock);
+ /* A timer might have just expired */
+ schedule_work(&rtc->irqwork);
return err;
}
EXPORT_SYMBOL_GPL(rtc_set_time);
err = -EINVAL;
mutex_unlock(&rtc->ops_lock);
+ /* A timer might have just expired */
+ schedule_work(&rtc->irqwork);
return err;
}
return err;
}
-int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
+int __rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
{
int err;
struct rtc_time before, now;
err = rtc_read_alarm_internal(rtc, alarm);
if (err)
return err;
- if (!alarm->enabled)
- return 0;
/* full-function RTCs won't have such missing fields */
if (rtc_valid_tm(&alarm->time) == 0)
alarm->time.tm_hour = now.tm_hour;
/* For simplicity, only support date rollover for now */
- if (alarm->time.tm_mday == -1) {
+ if (alarm->time.tm_mday < 1 || alarm->time.tm_mday > 31) {
alarm->time.tm_mday = now.tm_mday;
missing = day;
}
- if (alarm->time.tm_mon == -1) {
+ if ((unsigned)alarm->time.tm_mon >= 12) {
alarm->time.tm_mon = now.tm_mon;
if (missing == none)
missing = month;
done:
return 0;
}
-EXPORT_SYMBOL_GPL(rtc_read_alarm);
-int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
+int rtc_read_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
{
int err;
- err = rtc_valid_tm(&alarm->time);
- if (err != 0)
+ err = mutex_lock_interruptible(&rtc->ops_lock);
+ if (err)
return err;
+ if (rtc->ops == NULL)
+ err = -ENODEV;
+ else if (!rtc->ops->read_alarm)
+ err = -EINVAL;
+ else {
+ memset(alarm, 0, sizeof(struct rtc_wkalrm));
+ alarm->enabled = rtc->aie_timer.enabled;
+ alarm->time = rtc_ktime_to_tm(rtc->aie_timer.node.expires);
+ }
+ mutex_unlock(&rtc->ops_lock);
- err = mutex_lock_interruptible(&rtc->ops_lock);
+ return err;
+}
+EXPORT_SYMBOL_GPL(rtc_read_alarm);
+
+static int __rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
+{
+ struct rtc_time tm;
+ long now, scheduled;
+ int err;
+
+ err = rtc_valid_tm(&alarm->time);
if (err)
return err;
+ rtc_tm_to_time(&alarm->time, &scheduled);
+
+ /* Make sure we're not setting alarms in the past */
+ err = __rtc_read_time(rtc, &tm);
+ rtc_tm_to_time(&tm, &now);
+ if (scheduled <= now)
+ return -ETIME;
+ /*
+ * XXX - We just checked to make sure the alarm time is not
+ * in the past, but there is still a race window where if
+ * the is alarm set for the next second and the second ticks
+ * over right here, before we set the alarm.
+ */
if (!rtc->ops)
err = -ENODEV;
else
err = rtc->ops->set_alarm(rtc->dev.parent, alarm);
+ return err;
+}
+
+int rtc_set_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
+{
+ int err;
+
+ err = rtc_valid_tm(&alarm->time);
+ if (err != 0)
+ return err;
+
+ err = mutex_lock_interruptible(&rtc->ops_lock);
+ if (err)
+ return err;
+ if (rtc->aie_timer.enabled) {
+ rtc_timer_remove(rtc, &rtc->aie_timer);
+ }
+ rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time);
+ rtc->aie_timer.period = ktime_set(0, 0);
+ if (alarm->enabled) {
+ err = rtc_timer_enqueue(rtc, &rtc->aie_timer);
+ }
mutex_unlock(&rtc->ops_lock);
return err;
}
EXPORT_SYMBOL_GPL(rtc_set_alarm);
+/* Called once per device from rtc_device_register */
+int rtc_initialize_alarm(struct rtc_device *rtc, struct rtc_wkalrm *alarm)
+{
+ int err;
+ struct rtc_time now;
+
+ err = rtc_valid_tm(&alarm->time);
+ if (err != 0)
+ return err;
+
+ err = rtc_read_time(rtc, &now);
+ if (err)
+ return err;
+
+ err = mutex_lock_interruptible(&rtc->ops_lock);
+ if (err)
+ return err;
+
+ rtc->aie_timer.node.expires = rtc_tm_to_ktime(alarm->time);
+ rtc->aie_timer.period = ktime_set(0, 0);
+
+ /* Alarm has to be enabled & in the futrure for us to enqueue it */
+ if (alarm->enabled && (rtc_tm_to_ktime(now).tv64 <
+ rtc->aie_timer.node.expires.tv64)) {
+
+ rtc->aie_timer.enabled = 1;
+ timerqueue_add(&rtc->timerqueue, &rtc->aie_timer.node);
+ }
+ mutex_unlock(&rtc->ops_lock);
+ return err;
+}
+EXPORT_SYMBOL_GPL(rtc_initialize_alarm);
+
+
+
int rtc_alarm_irq_enable(struct rtc_device *rtc, unsigned int enabled)
{
int err = mutex_lock_interruptible(&rtc->ops_lock);
if (err)
return err;
- if (!rtc->ops)
+ if (rtc->aie_timer.enabled != enabled) {
+ if (enabled)
+ err = rtc_timer_enqueue(rtc, &rtc->aie_timer);
+ else
+ rtc_timer_remove(rtc, &rtc->aie_timer);
+ }
+
+ if (err)
+ /* nothing */;
+ else if (!rtc->ops)
err = -ENODEV;
else if (!rtc->ops->alarm_irq_enable)
err = -EINVAL;
#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
if (enabled == 0 && rtc->uie_irq_active) {
mutex_unlock(&rtc->ops_lock);
- return rtc_dev_update_irq_enable_emul(rtc, enabled);
+ return rtc_dev_update_irq_enable_emul(rtc, 0);
}
#endif
+ /* make sure we're changing state */
+ if (rtc->uie_rtctimer.enabled == enabled)
+ goto out;
- if (!rtc->ops)
- err = -ENODEV;
- else if (!rtc->ops->update_irq_enable)
+ if (rtc->uie_unsupported) {
err = -EINVAL;
- else
- err = rtc->ops->update_irq_enable(rtc->dev.parent, enabled);
+ goto out;
+ }
- mutex_unlock(&rtc->ops_lock);
+ if (enabled) {
+ struct rtc_time tm;
+ ktime_t now, onesec;
+
+ __rtc_read_time(rtc, &tm);
+ 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);
+ } else
+ rtc_timer_remove(rtc, &rtc->uie_rtctimer);
+out:
+ mutex_unlock(&rtc->ops_lock);
#ifdef CONFIG_RTC_INTF_DEV_UIE_EMUL
/*
* Enable emulation if the driver did not provide
err = rtc_dev_update_irq_enable_emul(rtc, enabled);
#endif
return err;
+
}
EXPORT_SYMBOL_GPL(rtc_update_irq_enable);
+
/**
- * rtc_update_irq - report RTC periodic, alarm, and/or update irqs
- * @rtc: the rtc device
- * @num: how many irqs are being reported (usually one)
- * @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF
- * Context: in_interrupt(), irqs blocked
+ * rtc_handle_legacy_irq - AIE, UIE and PIE event hook
+ * @rtc: pointer to the rtc device
+ *
+ * This function is called when an AIE, UIE or PIE mode interrupt
+ * has occurred (or been emulated).
+ *
+ * Triggers the registered irq_task function callback.
*/
-void rtc_update_irq(struct rtc_device *rtc,
- unsigned long num, unsigned long events)
+void rtc_handle_legacy_irq(struct rtc_device *rtc, int num, int mode)
{
- spin_lock(&rtc->irq_lock);
- rtc->irq_data = (rtc->irq_data + (num << 8)) | events;
- spin_unlock(&rtc->irq_lock);
+ unsigned long flags;
+
+ /* mark one irq of the appropriate mode */
+ spin_lock_irqsave(&rtc->irq_lock, flags);
+ rtc->irq_data = (rtc->irq_data + (num << 8)) | (RTC_IRQF|mode);
+ spin_unlock_irqrestore(&rtc->irq_lock, flags);
- spin_lock(&rtc->irq_task_lock);
+ /* call the task func */
+ spin_lock_irqsave(&rtc->irq_task_lock, flags);
if (rtc->irq_task)
rtc->irq_task->func(rtc->irq_task->private_data);
- spin_unlock(&rtc->irq_task_lock);
+ spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
wake_up_interruptible(&rtc->irq_queue);
kill_fasync(&rtc->async_queue, SIGIO, POLL_IN);
}
+
+
+/**
+ * rtc_aie_update_irq - AIE mode rtctimer hook
+ * @private: pointer to the rtc_device
+ *
+ * This functions is called when the aie_timer expires.
+ */
+void rtc_aie_update_irq(void *private)
+{
+ struct rtc_device *rtc = (struct rtc_device *)private;
+ rtc_handle_legacy_irq(rtc, 1, RTC_AF);
+}
+
+
+/**
+ * rtc_uie_update_irq - UIE mode rtctimer hook
+ * @private: pointer to the rtc_device
+ *
+ * This functions is called when the uie_timer expires.
+ */
+void rtc_uie_update_irq(void *private)
+{
+ struct rtc_device *rtc = (struct rtc_device *)private;
+ rtc_handle_legacy_irq(rtc, 1, RTC_UF);
+}
+
+
+/**
+ * rtc_pie_update_irq - PIE mode hrtimer hook
+ * @timer: pointer to the pie mode hrtimer
+ *
+ * This function is used to emulate PIE mode interrupts
+ * using an hrtimer. This function is called when the periodic
+ * hrtimer expires.
+ */
+enum hrtimer_restart rtc_pie_update_irq(struct hrtimer *timer)
+{
+ struct rtc_device *rtc;
+ ktime_t period;
+ int count;
+ rtc = container_of(timer, struct rtc_device, pie_timer);
+
+ period = ktime_set(0, NSEC_PER_SEC/rtc->irq_freq);
+ count = hrtimer_forward_now(timer, period);
+
+ rtc_handle_legacy_irq(rtc, count, RTC_PF);
+
+ return HRTIMER_RESTART;
+}
+
+/**
+ * rtc_update_irq - Triggered when a RTC interrupt occurs.
+ * @rtc: the rtc device
+ * @num: how many irqs are being reported (usually one)
+ * @events: mask of RTC_IRQF with one or more of RTC_PF, RTC_AF, RTC_UF
+ * Context: any
+ */
+void rtc_update_irq(struct rtc_device *rtc,
+ unsigned long num, unsigned long events)
+{
+ pm_stay_awake(rtc->dev.parent);
+ schedule_work(&rtc->irqwork);
+}
EXPORT_SYMBOL_GPL(rtc_update_irq);
-static int __rtc_match(struct device *dev, void *data)
+static int __rtc_match(struct device *dev, const void *data)
{
- char *name = (char *)data;
+ const char *name = data;
if (strcmp(dev_name(dev), name) == 0)
return 1;
return 0;
}
-struct rtc_device *rtc_class_open(char *name)
+struct rtc_device *rtc_class_open(const char *name)
{
struct device *dev;
struct rtc_device *rtc = NULL;
}
EXPORT_SYMBOL_GPL(rtc_irq_unregister);
+static int rtc_update_hrtimer(struct rtc_device *rtc, int enabled)
+{
+ /*
+ * We always cancel the timer here first, because otherwise
+ * we could run into BUG_ON(timer->state != HRTIMER_STATE_CALLBACK);
+ * when we manage to start the timer before the callback
+ * returns HRTIMER_RESTART.
+ *
+ * We cannot use hrtimer_cancel() here as a running callback
+ * could be blocked on rtc->irq_task_lock and hrtimer_cancel()
+ * would spin forever.
+ */
+ if (hrtimer_try_to_cancel(&rtc->pie_timer) < 0)
+ return -1;
+
+ if (enabled) {
+ ktime_t period = ktime_set(0, NSEC_PER_SEC / rtc->irq_freq);
+
+ hrtimer_start(&rtc->pie_timer, period, HRTIMER_MODE_REL);
+ }
+ return 0;
+}
+
/**
* rtc_irq_set_state - enable/disable 2^N Hz periodic IRQs
* @rtc: the rtc device
int err = 0;
unsigned long flags;
- if (rtc->ops->irq_set_state == NULL)
- return -ENXIO;
-
+retry:
spin_lock_irqsave(&rtc->irq_task_lock, flags);
if (rtc->irq_task != NULL && task == NULL)
err = -EBUSY;
if (rtc->irq_task != task)
err = -EACCES;
+ if (!err) {
+ if (rtc_update_hrtimer(rtc, enabled) < 0) {
+ spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
+ cpu_relax();
+ goto retry;
+ }
+ rtc->pie_enabled = enabled;
+ }
spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
-
- if (err == 0)
- err = rtc->ops->irq_set_state(rtc->dev.parent, enabled);
-
return err;
}
EXPORT_SYMBOL_GPL(rtc_irq_set_state);
int err = 0;
unsigned long flags;
- if (rtc->ops->irq_set_freq == NULL)
- return -ENXIO;
-
+ if (freq <= 0 || freq > RTC_MAX_FREQ)
+ return -EINVAL;
+retry:
spin_lock_irqsave(&rtc->irq_task_lock, flags);
if (rtc->irq_task != NULL && task == NULL)
err = -EBUSY;
if (rtc->irq_task != task)
err = -EACCES;
- spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
-
- if (err == 0) {
- err = rtc->ops->irq_set_freq(rtc->dev.parent, freq);
- if (err == 0)
- rtc->irq_freq = freq;
+ if (!err) {
+ rtc->irq_freq = freq;
+ if (rtc->pie_enabled && rtc_update_hrtimer(rtc, 1) < 0) {
+ spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
+ cpu_relax();
+ goto retry;
+ }
}
+ spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
return err;
}
EXPORT_SYMBOL_GPL(rtc_irq_set_freq);
+
+/**
+ * rtc_timer_enqueue - Adds a rtc_timer to the rtc_device timerqueue
+ * @rtc rtc device
+ * @timer timer being added.
+ *
+ * Enqueues a timer onto the rtc devices timerqueue and sets
+ * the next alarm event appropriately.
+ *
+ * Sets the enabled bit on the added timer.
+ *
+ * Must hold ops_lock for proper serialization of timerqueue
+ */
+static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer)
+{
+ timer->enabled = 1;
+ timerqueue_add(&rtc->timerqueue, &timer->node);
+ if (&timer->node == timerqueue_getnext(&rtc->timerqueue)) {
+ struct rtc_wkalrm alarm;
+ int err;
+ alarm.time = rtc_ktime_to_tm(timer->node.expires);
+ alarm.enabled = 1;
+ err = __rtc_set_alarm(rtc, &alarm);
+ if (err == -ETIME)
+ schedule_work(&rtc->irqwork);
+ else if (err) {
+ timerqueue_del(&rtc->timerqueue, &timer->node);
+ timer->enabled = 0;
+ return err;
+ }
+ }
+ return 0;
+}
+
+static void rtc_alarm_disable(struct rtc_device *rtc)
+{
+ if (!rtc->ops || !rtc->ops->alarm_irq_enable)
+ return;
+
+ rtc->ops->alarm_irq_enable(rtc->dev.parent, false);
+}
+
+/**
+ * rtc_timer_remove - Removes a rtc_timer from the rtc_device timerqueue
+ * @rtc rtc device
+ * @timer timer being removed.
+ *
+ * Removes a timer onto the rtc devices timerqueue and sets
+ * the next alarm event appropriately.
+ *
+ * Clears the enabled bit on the removed timer.
+ *
+ * Must hold ops_lock for proper serialization of timerqueue
+ */
+static void rtc_timer_remove(struct rtc_device *rtc, struct rtc_timer *timer)
+{
+ struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue);
+ timerqueue_del(&rtc->timerqueue, &timer->node);
+ timer->enabled = 0;
+ if (next == &timer->node) {
+ struct rtc_wkalrm alarm;
+ int err;
+ next = timerqueue_getnext(&rtc->timerqueue);
+ if (!next) {
+ rtc_alarm_disable(rtc);
+ return;
+ }
+ alarm.time = rtc_ktime_to_tm(next->expires);
+ alarm.enabled = 1;
+ err = __rtc_set_alarm(rtc, &alarm);
+ if (err == -ETIME)
+ schedule_work(&rtc->irqwork);
+ }
+}
+
+/**
+ * rtc_timer_do_work - Expires rtc timers
+ * @rtc rtc device
+ * @timer timer being removed.
+ *
+ * Expires rtc timers. Reprograms next alarm event if needed.
+ * Called via worktask.
+ *
+ * Serializes access to timerqueue via ops_lock mutex
+ */
+void rtc_timer_do_work(struct work_struct *work)
+{
+ struct rtc_timer *timer;
+ struct timerqueue_node *next;
+ ktime_t now;
+ struct rtc_time tm;
+
+ struct rtc_device *rtc =
+ container_of(work, struct rtc_device, irqwork);
+
+ mutex_lock(&rtc->ops_lock);
+again:
+ pm_relax(rtc->dev.parent);
+ __rtc_read_time(rtc, &tm);
+ now = rtc_tm_to_ktime(tm);
+ while ((next = timerqueue_getnext(&rtc->timerqueue))) {
+ if (next->expires.tv64 > now.tv64)
+ break;
+
+ /* expire timer */
+ timer = container_of(next, struct rtc_timer, node);
+ timerqueue_del(&rtc->timerqueue, &timer->node);
+ timer->enabled = 0;
+ if (timer->task.func)
+ timer->task.func(timer->task.private_data);
+
+ /* Re-add/fwd periodic timers */
+ if (ktime_to_ns(timer->period)) {
+ timer->node.expires = ktime_add(timer->node.expires,
+ timer->period);
+ timer->enabled = 1;
+ timerqueue_add(&rtc->timerqueue, &timer->node);
+ }
+ }
+
+ /* Set next alarm */
+ if (next) {
+ struct rtc_wkalrm alarm;
+ int err;
+ alarm.time = rtc_ktime_to_tm(next->expires);
+ alarm.enabled = 1;
+ err = __rtc_set_alarm(rtc, &alarm);
+ if (err == -ETIME)
+ goto again;
+ } else
+ rtc_alarm_disable(rtc);
+
+ mutex_unlock(&rtc->ops_lock);
+}
+
+
+/* rtc_timer_init - Initializes an rtc_timer
+ * @timer: timer to be intiialized
+ * @f: function pointer to be called when timer fires
+ * @data: private data passed to function pointer
+ *
+ * Kernel interface to initializing an rtc_timer.
+ */
+void rtc_timer_init(struct rtc_timer *timer, void (*f)(void* p), void* data)
+{
+ timerqueue_init(&timer->node);
+ timer->enabled = 0;
+ timer->task.func = f;
+ timer->task.private_data = data;
+}
+
+/* rtc_timer_start - Sets an rtc_timer to fire in the future
+ * @ rtc: rtc device to be used
+ * @ timer: timer being set
+ * @ expires: time at which to expire the timer
+ * @ period: period that the timer will recur
+ *
+ * Kernel interface to set an rtc_timer
+ */
+int rtc_timer_start(struct rtc_device *rtc, struct rtc_timer* timer,
+ ktime_t expires, ktime_t period)
+{
+ int ret = 0;
+ mutex_lock(&rtc->ops_lock);
+ if (timer->enabled)
+ rtc_timer_remove(rtc, timer);
+
+ timer->node.expires = expires;
+ timer->period = period;
+
+ ret = rtc_timer_enqueue(rtc, timer);
+
+ mutex_unlock(&rtc->ops_lock);
+ return ret;
+}
+
+/* rtc_timer_cancel - Stops an rtc_timer
+ * @ rtc: rtc device to be used
+ * @ timer: timer being set
+ *
+ * Kernel interface to cancel an rtc_timer
+ */
+int rtc_timer_cancel(struct rtc_device *rtc, struct rtc_timer* timer)
+{
+ int ret = 0;
+ mutex_lock(&rtc->ops_lock);
+ if (timer->enabled)
+ rtc_timer_remove(rtc, timer);
+ mutex_unlock(&rtc->ops_lock);
+ return ret;
+}
+
+
Code Review / linux-3.10.git / blobdiff