diff --git a/include/dt-bindings/mfd/at91-usart.h b/include/dt-bindings/mfd/at91-usart.h
new file mode 100644
index 0000000..2de5bc3
--- /dev/null
+++ b/include/dt-bindings/mfd/at91-usart.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This header provides macros for AT91 USART DT bindings.
+ *
+ * Copyright (C) 2018 Microchip Technology
+ *
+ * Author: Radu Pirea <radu.pirea@microchip.com>
+ *
+ */
+
+#ifndef __DT_BINDINGS_AT91_USART_H__
+#define __DT_BINDINGS_AT91_USART_H__
+
+#define AT91_USART_MODE_SERIAL	0
+#define AT91_USART_MODE_SPI	1
+
+#endif /* __DT_BINDINGS_AT91_USART_H__ */