[PATCH] HCDs support new DMA APIs (part 2 of 2)

- teaches the shared "hcd" code to set urb->*_dma whenever the device
  driver didn't, by creating singleshot mappings.

drivers/usb/core/hcd.c

@@ -29,6 +29,7 @@
 #include <linux/slab.h>
 #include <linux/completion.h>
 #include <linux/uts.h>			/* for UTS_SYSNAME */
+#include <linux/pci.h>			/* for hcd->pdev and dma addressing */
 #include <asm/byteorder.h>
 
 
@@ -1021,6 +1022,24 @@ static int hcd_submit_urb (struct urb *urb, int mem_flags)
 	if (status)
 		return status;
 
+	/* lower level hcd code should use *_dma exclusively */
+	if (!(urb->transfer_flags & URB_NO_DMA_MAP)) {
+		if (usb_pipecontrol (urb->pipe))
+			urb->setup_dma = pci_map_single (
+					hcd->pdev,
+					urb->setup_packet,
+					sizeof (struct usb_ctrlrequest),
+					PCI_DMA_TODEVICE);
+		if (urb->transfer_buffer_length != 0)
+			urb->transfer_dma = pci_map_single (
+					hcd->pdev,
+					urb->transfer_buffer,
+					urb->transfer_buffer_length,
+					usb_pipein (urb->pipe)
+					    ? PCI_DMA_FROMDEVICE
+					    : PCI_DMA_TODEVICE);
+	}
+
 	/* increment urb's reference count as part of giving it to the HCD
 	 * (which now controls it).  HCD guarantees that it either returns
 	 * an error or calls giveback(), but not both.
@@ -1289,6 +1308,20 @@ void usb_hcd_giveback_urb (struct usb_hcd *hcd, struct urb *urb)
 		dbg ("giveback urb %p status %d len %d",
 			urb, urb->status, urb->actual_length);
 
+	/* lower level hcd code should use *_dma exclusively */
+	if (!(urb->transfer_flags & URB_NO_DMA_MAP)) {
+		if (usb_pipecontrol (urb->pipe))
+			pci_unmap_single (hcd->pdev, urb->setup_dma,
+					sizeof (struct usb_ctrlrequest),
+					PCI_DMA_TODEVICE);
+		if (urb->transfer_buffer_length != 0)
+			pci_unmap_single (hcd->pdev, urb->transfer_dma,
+					urb->transfer_buffer_length,
+					usb_pipein (urb->pipe)
+					    ? PCI_DMA_FROMDEVICE
+					    : PCI_DMA_TODEVICE);
+	}
+
 	/* pass ownership to the completion handler */
 	urb->complete (urb);
 	usb_put_urb (urb);