diff options
Diffstat (limited to 'drivers/char/ip27-rtc.c')
| -rw-r--r-- | drivers/char/ip27-rtc.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/char/ip27-rtc.c b/drivers/char/ip27-rtc.c index 86e6538a77b..ec9d0443d92 100644 --- a/drivers/char/ip27-rtc.c +++ b/drivers/char/ip27-rtc.c @@ -27,6 +27,7 @@ #include <linux/bcd.h> #include <linux/module.h> #include <linux/kernel.h> +#include <linux/smp_lock.h> #include <linux/types.h> #include <linux/miscdevice.h> #include <linux/ioport.h> @@ -163,15 +164,18 @@ static long rtc_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) static int rtc_open(struct inode *inode, struct file *file) { + lock_kernel(); spin_lock_irq(&rtc_lock); if (rtc_status & RTC_IS_OPEN) { spin_unlock_irq(&rtc_lock); + unlock_kernel(); return -EBUSY; } rtc_status |= RTC_IS_OPEN; spin_unlock_irq(&rtc_lock); + unlock_kernel(); return 0; } |