USB: HCD: Add driver hooks for (un)?map_urb_for_dma

Provide optional hooks for the host controller driver to override the
default DMA mapping and unmapping routines.  In general, these shouldn't
be necessary unless the host controller has special DMA requirements,
such as alignment contraints.  If these are not specified, the
general usb_hcd_(un)?map_urb_for_dma functions will be used instead.
Also, pass the status to unmap_urb_for_dma so it can know whether the
DMA buffer has been overwritten.

Finally, add a flag to be used by these implementations if they
allocated a temporary buffer so it can be freed properly when unmapping.

Signed-off-by: Robert Morell <rmorell@nvidia.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/usb.h b/include/linux/usb.h
index bd69b65f3356..e63efeb378e3 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -976,6 +976,7 @@ extern int usb_disabled(void);
 #define URB_SETUP_MAP_SINGLE    0x00100000      /* Setup packet DMA mapped */
 #define URB_SETUP_MAP_LOCAL     0x00200000      /* HCD-local setup packet */
 #define URB_DMA_SG_COMBINED     0x00400000      /* S-G entries were combined */
+#define URB_ALIGNED_TEMP_BUFFER 0x00800000      /* Temp buffer was alloc'd */
 
 struct usb_iso_packet_descriptor {
         unsigned int offset;