From 8853c202b4a91713dbfb4d9b6e1c87cc2aa12392 Mon Sep 17 00:00:00 2001 From: Jiri Kosina Date: Wed, 28 Nov 2007 16:22:03 -0800 Subject: RTC: convert mutex to bitfield RTC code is using mutex to assure exclusive access to /dev/rtc. This is however wrong usage, as it leaves the mutex locked when returning into userspace, which is unacceptable. Convert rtc->char_lock into bit operation. Signed-off-by: Jiri Kosina Acked-by: Alessandro Zummo Cc: David Brownell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/interface.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/rtc/interface.c') diff --git a/drivers/rtc/interface.c b/drivers/rtc/interface.c index de0da545c7a..a4f56e95cf9 100644 --- a/drivers/rtc/interface.c +++ b/drivers/rtc/interface.c @@ -293,7 +293,7 @@ int rtc_irq_register(struct rtc_device *rtc, struct rtc_task *task) return -EINVAL; /* Cannot register while the char dev is in use */ - if (!(mutex_trylock(&rtc->char_lock))) + if (test_and_set_bit(RTC_DEV_BUSY, &rtc->flags)) return -EBUSY; spin_lock_irq(&rtc->irq_task_lock); @@ -303,7 +303,7 @@ int rtc_irq_register(struct rtc_device *rtc, struct rtc_task *task) } spin_unlock_irq(&rtc->irq_task_lock); - mutex_unlock(&rtc->char_lock); + clear_bit(RTC_DEV_BUSY, &rtc->flags); return retval; } -- cgit v1.2.3