diff --git a/drivers/misc/ibmasm/ibmasm.h b/drivers/misc/ibmasm/ibmasm.h
index 9b08344..5bd1277 100644
--- a/drivers/misc/ibmasm/ibmasm.h
+++ b/drivers/misc/ibmasm/ibmasm.h
@@ -211,7 +211,7 @@
 void ibmasmfs_add_sp(struct service_processor *sp);
 
 /* uart */
-#ifdef CONFIG_SERIAL_8250
+#if IS_ENABLED(CONFIG_SERIAL_8250)
 void ibmasm_register_uart(struct service_processor *sp);
 void ibmasm_unregister_uart(struct service_processor *sp);
 #else