diff --git a/drivers/platform/x86/acer-wmi.c b/drivers/platform/x86/acer-wmi.c
index a7bcad7eb093e8917f87f281995f8cdb9982028a..38b34a73866a893e030bca2345e6c383129d7e19 100644
--- a/drivers/platform/x86/acer-wmi.c
+++ b/drivers/platform/x86/acer-wmi.c
@@ -84,7 +84,7 @@ MODULE_LICENSE("GPL");
  */
 #define AMW0_GUID1		"67C3371D-95A3-4C37-BB61-DD47B491DAAB"
 #define AMW0_GUID2		"431F16ED-0C2B-444C-B267-27DEB140CF9C"
-#define WMID_GUID1		"6AF4F258-B401-42fd-BE91-3D4AC2D7C0D3"
+#define WMID_GUID1		"6AF4F258-B401-42FD-BE91-3D4AC2D7C0D3"
 #define WMID_GUID2		"95764E09-FB56-4e83-B31A-37761F60994A"
 #define WMID_GUID3		"61EF69EA-865C-4BC3-A502-A0DEBA0CB531"