diff --git a/drivers/platform/x86/samsung-laptop.c b/drivers/platform/x86/samsung-laptop.c
index b7c67c87f47b96006428014e560bceca7be97925..d1142e3174337eedad8a4d7aa93e75d9c3510a2d 100644
--- a/drivers/platform/x86/samsung-laptop.c
+++ b/drivers/platform/x86/samsung-laptop.c
@@ -25,6 +25,7 @@
 #include <linux/acpi.h>
 #include <linux/seq_file.h>
 #include <linux/debugfs.h>
+#include <linux/ctype.h>
 
 /*
  * This driver is needed because a number of Samsung laptops do not hook