diff --git a/include/osi_dma.h b/include/osi_dma.h
index c21221f..c7a800f 100644
--- a/include/osi_dma.h
+++ b/include/osi_dma.h
@@ -247,6 +247,11 @@
 #endif /* OSI_DEBUG */
 /** @} */
 
+/**
+ * @brief Maximum buffer length per DMA descriptor (16KB - 1).
+ */
+#define OSI_TX_MAX_BUFF_SIZE		0x3FFFU
+
 /**
  * @brief OSI packet error stats
  */