diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c
index efb959d..9a85566 100644
--- a/drivers/acpi/dock.c
+++ b/drivers/acpi/dock.c
@@ -33,6 +33,8 @@
 #include <acpi/acpi_bus.h>
 #include <acpi/acpi_drivers.h>
 
+#define PREFIX "ACPI: "
+
 #define ACPI_DOCK_DRIVER_DESCRIPTION "ACPI Dock Station Driver"
 
 ACPI_MODULE_NAME("dock");