RTC: periodic irq fix

Add kernel/kernel and kernel/user locking for the periodic irq feature of
the rtc class.

PIE ioctls are also supported.

Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alessandro Zummo
2007-10-16 01:28:15 -07:00
committed by Linus Torvalds
parent 16a72c455a
commit d691eb901e
3 changed files with 24 additions and 25 deletions

View File

@@ -210,6 +210,10 @@ int rtc_irq_register(struct rtc_device *rtc, struct rtc_task *task)
if (task == NULL || task->func == NULL)
return -EINVAL;
/* Cannot register while the char dev is in use */
if (!(mutex_trylock(&rtc->char_lock)))
return -EBUSY;
spin_lock_irq(&rtc->irq_task_lock);
if (rtc->irq_task == NULL) {
rtc->irq_task = task;
@@ -217,13 +221,14 @@ int rtc_irq_register(struct rtc_device *rtc, struct rtc_task *task)
}
spin_unlock_irq(&rtc->irq_task_lock);
mutex_unlock(&rtc->char_lock);
return retval;
}
EXPORT_SYMBOL_GPL(rtc_irq_register);
void rtc_irq_unregister(struct rtc_device *rtc, struct rtc_task *task)
{
spin_lock_irq(&rtc->irq_task_lock);
if (rtc->irq_task == task)
rtc->irq_task = NULL;
@@ -240,8 +245,10 @@ int rtc_irq_set_state(struct rtc_device *rtc, struct rtc_task *task, int enabled
return -ENXIO;
spin_lock_irqsave(&rtc->irq_task_lock, flags);
if (rtc->irq_task != NULL && task == NULL)
err = -EBUSY;
if (rtc->irq_task != task)
err = -ENXIO;
err = -EACCES;
spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
if (err == 0)
@@ -260,8 +267,10 @@ int rtc_irq_set_freq(struct rtc_device *rtc, struct rtc_task *task, int freq)
return -ENXIO;
spin_lock_irqsave(&rtc->irq_task_lock, flags);
if (rtc->irq_task != NULL && task == NULL)
err = -EBUSY;
if (rtc->irq_task != task)
err = -ENXIO;
err = -EACCES;
spin_unlock_irqrestore(&rtc->irq_task_lock, flags);
if (err == 0) {