1 files changed, 2 insertions, 2 deletions

diff --git a/include/acpi/platform/acenv.h b/include/acpi/platform/acenv.h
index e62f10d9a7d8..fa7689a6fc4b 100644
--- a/include/acpi/platform/acenv.h
+++ b/include/acpi/platform/acenv.h
@@ -311,8 +311,8 @@ typedef char *va_list;
 #define ACPI_MEMCMP(s1,s2,n)    acpi_ut_memcmp((const char *)(s1), (const char *)(s2), (acpi_size)(n))
 #define ACPI_MEMCPY(d,s,n)      (void) acpi_ut_memcpy ((d), (s), (acpi_size)(n))
 #define ACPI_MEMSET(d,v,n)      (void) acpi_ut_memset ((d), (v), (acpi_size)(n))
-#define ACPI_TOUPPER            acpi_ut_to_upper
-#define ACPI_TOLOWER            acpi_ut_to_lower
+#define ACPI_TOUPPER(c)         acpi_ut_to_upper ((int) (c))
+#define ACPI_TOLOWER(c)         acpi_ut_to_lower ((int) (c))
 
 #endif                          /* ACPI_USE_SYSTEM_CLIBRARY */