diff --git a/sound/drivers/portman2x4.c b/sound/drivers/portman2x4.c
index f2b0ba2..f664823 100644
--- a/sound/drivers/portman2x4.c
+++ b/sound/drivers/portman2x4.c
@@ -43,6 +43,7 @@
 #include <linux/spinlock.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
+#include <linux/module.h>
 #include <sound/core.h>
 #include <sound/initval.h>
 #include <sound/rawmidi.h>