diff --git a/include/linux/libata.h b/include/linux/libata.h
index 80233fd..225bfc5 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -1429,6 +1429,28 @@
 	return from_jiffies + msecs_to_jiffies(timeout_msecs);
 }
 
+/* Don't open code these in drivers as there are traps. Firstly the range may
+   change in future hardware and specs, secondly 0xFF means 'no DMA' but is
+   > UDMA_0. Dyma ddreigiau */
+
+static inline int ata_using_mwdma(struct ata_device *adev)
+{
+	if (adev->dma_mode >= XFER_MW_DMA_0 && adev->dma_mode <= XFER_MW_DMA_4)
+		return 1;
+	return 0;
+}
+
+static inline int ata_using_udma(struct ata_device *adev)
+{
+	if (adev->dma_mode >= XFER_UDMA_0 && adev->dma_mode <= XFER_UDMA_7)
+		return 1;
+	return 0;
+}
+
+static inline int ata_dma_enabled(struct ata_device *adev)
+{
+	return (adev->dma_mode == 0xFF ? 0 : 1);
+}
 
 /**************************************************************************
  * PMP - drivers/ata/libata-pmp.c