1 files changed, 15 insertions, 2 deletions

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 0b8ff7d257ea..ec09ce9a6012 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -28,6 +28,7 @@
 #include <linux/workqueue.h>
 #include <linux/freezer.h>
 #include <linux/compat.h>
+#include <linux/module.h>
 
 #include "posix-timers.h"
 
@@ -56,9 +57,9 @@ static ktime_t freezer_delta;
 static DEFINE_SPINLOCK(freezer_delta_lock);
 #endif
 
+#ifdef CONFIG_RTC_CLASS
 static struct wakeup_source *ws;
 
-#ifdef CONFIG_RTC_CLASS
 /* rtc timer and device for setting alarm wakeups at suspend */
 static struct rtc_timer         rtctimer;
 static struct rtc_device        *rtcdev;
@@ -89,6 +90,7 @@ static int alarmtimer_rtc_add_device(struct device *dev,
 {
         unsigned long flags;
         struct rtc_device *rtc = to_rtc_device(dev);
+        struct wakeup_source *__ws;
 
         if (rtcdev)
                 return -EBUSY;
@@ -98,13 +100,25 @@ static int alarmtimer_rtc_add_device(struct device *dev,
         if (!device_may_wakeup(rtc->dev.parent))
                 return -1;
 
+        __ws = wakeup_source_register("alarmtimer");
+
         spin_lock_irqsave(&rtcdev_lock, flags);
         if (!rtcdev) {
+                if (!try_module_get(rtc->owner)) {
+                        spin_unlock_irqrestore(&rtcdev_lock, flags);
+                        return -1;
+                }
+
                 rtcdev = rtc;
                 /* hold a reference so it doesn't go away */
                 get_device(dev);
+                ws = __ws;
+                __ws = NULL;
         }
         spin_unlock_irqrestore(&rtcdev_lock, flags);
+
+        wakeup_source_unregister(__ws);
+
         return 0;
 }
 
@@ -860,7 +874,6 @@ static int __init alarmtimer_init(void)
                 error = PTR_ERR(pdev);
                 goto out_drv;
         }
-        ws = wakeup_source_register("alarmtimer");
         return 0;
 
 out_drv: