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 <jkosina@suse.cz>
Acked-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>
diff --git a/include/linux/rtc.h b/include/linux/rtc.h
index 6d5e4a4..f2d0d15 100644
--- a/include/linux/rtc.h
+++ b/include/linux/rtc.h
@@ -133,6 +133,9 @@
#define RTC_DEVICE_NAME_SIZE 20
struct rtc_task;
+/* flags */
+#define RTC_DEV_BUSY 0
+
struct rtc_device
{
struct device dev;
@@ -145,7 +148,7 @@
struct mutex ops_lock;
struct cdev char_dev;
- struct mutex char_lock;
+ unsigned long flags;
unsigned long irq_data;
spinlock_t irq_lock;