diff --git a/drivers/video/pm3fb.c b/drivers/video/pm3fb.c
index e0dad948467b..2e11b601c488 100644
--- a/drivers/video/pm3fb.c
+++ b/drivers/video/pm3fb.c
@@ -67,6 +67,7 @@
 #include <linux/init.h>
 #include <linux/pci.h>
 #include <linux/ioport.h>
+#include <linux/ctype.h>
 
 #include <video/fbcon.h>
 #include <video/fbcon-mfb.h>
@@ -2594,7 +2595,7 @@ static char *pm3fb_boardnum_setup(char *options, unsigned long *bn)
 {
 	char *next;
 
-	if (!(CHAR_IS_NUM(options[0]))) {
+	if (!(isdigit(options[0]))) {
 		(*bn) = 0;
 		return (options);
 	}
diff --git a/include/video/pm3fb.h b/include/video/pm3fb.h
index 8d3cef5d87a2..6f4ea808cf74 100644
--- a/include/video/pm3fb.h
+++ b/include/video/pm3fb.h
@@ -1142,9 +1142,6 @@
 /* do we want accelerated console  */
 #define PM3FB_USE_ACCEL 1
 
-/* useful ? */
-#define CHAR_IS_NUM(a)  ((((a) >= '0') && ((a) <= '9')) ? 1 : 0)
-
 /* for driver debugging ONLY */
 /* 0 = assert only, 1 = error, 2 = info, 3+ = verbose */
 /* define PM3FB_MASTER_DEBUG 1 */