diff --git a/drivers/char/mbcs.c b/drivers/char/mbcs.c
index 0385650..6363547 100644
--- a/drivers/char/mbcs.c
+++ b/drivers/char/mbcs.c
@@ -22,6 +22,7 @@
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/mm.h>
+#include <linux/fs.h>
 #include <linux/uio.h>
 #include <asm/io.h>
 #include <asm/uaccess.h>
@@ -447,15 +448,15 @@
 	loff_t newpos;
 
 	switch (whence) {
-	case 0:		/* SEEK_SET */
+	case SEEK_SET:
 		newpos = off;
 		break;
 
-	case 1:		/* SEEK_CUR */
+	case SEEK_CUR:
 		newpos = filp->f_pos + off;
 		break;
 
-	case 2:		/* SEEK_END */
+	case SEEK_END:
 		newpos = MBCS_SRAM_SIZE + off;
 		break;