diff --git a/drivers/staging/rtl8188eu/include/osdep_service.h b/drivers/staging/rtl8188eu/include/osdep_service.h
index a52dcd56229b..3ddaa34c761a 100644
--- a/drivers/staging/rtl8188eu/include/osdep_service.h
+++ b/drivers/staging/rtl8188eu/include/osdep_service.h
@@ -154,7 +154,6 @@ u32  _rtw_down_sema(struct semaphore *sema);
 
 void _rtw_init_queue(struct __queue *pqueue);
 
-u32  rtw_systime_to_ms(u32 systime);
 u32  rtw_ms_to_systime(u32 ms);
 s32  rtw_get_passing_time_ms(u32 start);
 
diff --git a/drivers/staging/rtl8188eu/os_dep/osdep_service.c b/drivers/staging/rtl8188eu/os_dep/osdep_service.c
index 93c76d7e8181..96f8eb88b06d 100644
--- a/drivers/staging/rtl8188eu/os_dep/osdep_service.c
+++ b/drivers/staging/rtl8188eu/os_dep/osdep_service.c
@@ -77,11 +77,6 @@ void	_rtw_init_queue(struct __queue *pqueue)
 	spin_lock_init(&(pqueue->lock));
 }
 
-inline u32 rtw_systime_to_ms(u32 systime)
-{
-	return systime * 1000 / HZ;
-}
-
 inline u32 rtw_ms_to_systime(u32 ms)
 {
 	return ms * HZ / 1000;
@@ -90,7 +85,7 @@ inline u32 rtw_ms_to_systime(u32 ms)
 /*  the input parameter start must be in jiffies */
 inline s32 rtw_get_passing_time_ms(u32 start)
 {
-	return rtw_systime_to_ms(jiffies-start);
+	return jiffies_to_msecs(jiffies-start);
 }
 
 struct net_device *rtw_alloc_etherdev_with_old_priv(int sizeof_priv,