diff --git a/include/efi_api.h b/include/efi_api.h
index 9bd70b0f18..e1cdaf5247 100644
--- a/include/efi_api.h
+++ b/include/efi_api.h
@@ -817,7 +817,7 @@ struct efi_simple_text_output_protocol {
 
 struct efi_input_key {
 	u16 scan_code;
-	s16 unicode_char;
+	u16 unicode_char;
 };
 
 #define EFI_SHIFT_STATE_INVALID		0x00000000