diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index 8d065d6ec956..1e98a7e6bccc 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -141,19 +141,6 @@ memory back to the pool before you destroy it.
 Part Ic - DMA addressing limitations
 ------------------------------------
 
-int
-dma_supported(struct device *dev, u64 mask)
-
-Checks to see if the device can support DMA to the memory described by
-mask.
-
-Returns: 1 if it can and 0 if it can't.
-
-Notes: This routine merely tests to see if the mask is possible.  It
-won't change the current mask settings.  It is more intended as an
-internal API for use by the platform than an external API for use by
-driver writers.
-
 int
 dma_set_mask_and_coherent(struct device *dev, u64 mask)
 
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index c63d82c91f10..48c92bf78bd0 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -589,7 +589,7 @@ static int ehci_run (struct usb_hcd *hcd)
 	 * streaming mappings for I/O buffers, like pci_map_single(),
 	 * can return segments above 4GB, if the device allows.
 	 *
-	 * NOTE:  the dma mask is visible through dma_supported(), so
+	 * NOTE:  the dma mask is visible through dev->dma_mask, so
 	 * drivers can pass this info along ... like NETIF_F_HIGHDMA,
 	 * Scsi_Host.highmem_io, and so forth.  It's readonly to all
 	 * host side drivers though.
diff --git a/drivers/usb/host/fotg210-hcd.c b/drivers/usb/host/fotg210-hcd.c
index 787f4e3d16d8..2341af4f3490 100644
--- a/drivers/usb/host/fotg210-hcd.c
+++ b/drivers/usb/host/fotg210-hcd.c
@@ -5063,7 +5063,7 @@ static int fotg210_run(struct usb_hcd *hcd)
 	 * streaming mappings for I/O buffers, like pci_map_single(),
 	 * can return segments above 4GB, if the device allows.
 	 *
-	 * NOTE:  the dma mask is visible through dma_supported(), so
+	 * NOTE:  the dma mask is visible through dev->dma_mask, so
 	 * drivers can pass this info along ... like NETIF_F_HIGHDMA,
 	 * Scsi_Host.highmem_io, and so forth.  It's readonly to all
 	 * host side drivers though.
diff --git a/drivers/usb/host/oxu210hp-hcd.c b/drivers/usb/host/oxu210hp-hcd.c
index fe3bd1cb8b6b..1f139d82cee0 100644
--- a/drivers/usb/host/oxu210hp-hcd.c
+++ b/drivers/usb/host/oxu210hp-hcd.c
@@ -2721,7 +2721,7 @@ static int oxu_run(struct usb_hcd *hcd)
 	 * streaming mappings for I/O buffers, like pci_map_single(),
 	 * can return segments above 4GB, if the device allows.
 	 *
-	 * NOTE:  the dma mask is visible through dma_supported(), so
+	 * NOTE:  the dma mask is visible through dev->dma_mask, so
 	 * drivers can pass this info along ... like NETIF_F_HIGHDMA,
 	 * Scsi_Host.highmem_io, and so forth.  It's readonly to all
 	 * host side drivers though.