diff --git a/sound/drivers/opl4/opl4_proc.c b/sound/drivers/opl4/opl4_proc.c
index f4b4e74..e552ec3 100644
--- a/sound/drivers/opl4/opl4_proc.c
+++ b/sound/drivers/opl4/opl4_proc.c
@@ -28,13 +28,13 @@
 {
 	struct snd_opl4 *opl4 = entry->private_data;
 
-	down(&opl4->access_mutex);
+	mutex_lock(&opl4->access_mutex);
 	if (opl4->memory_access) {
-		up(&opl4->access_mutex);
+		mutex_unlock(&opl4->access_mutex);
 		return -EBUSY;
 	}
 	opl4->memory_access++;
-	up(&opl4->access_mutex);
+	mutex_unlock(&opl4->access_mutex);
 	return 0;
 }
 
@@ -43,9 +43,9 @@
 {
 	struct snd_opl4 *opl4 = entry->private_data;
 
-	down(&opl4->access_mutex);
+	mutex_lock(&opl4->access_mutex);
 	opl4->memory_access--;
-	up(&opl4->access_mutex);
+	mutex_unlock(&opl4->access_mutex);
 	return 0;
 }