diff --git a/drivers/char/moxa.c b/drivers/char/moxa.c
index 166495d..107b0bd 100644
--- a/drivers/char/moxa.c
+++ b/drivers/char/moxa.c
@@ -43,6 +43,7 @@
 #include <linux/pci.h>
 #include <linux/init.h>
 #include <linux/bitops.h>
+#include <linux/slab.h>
 
 #include <asm/system.h>
 #include <asm/io.h>