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USB: remove uses of URB_NO_SETUP_DMA_MAP

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This patch (as1350) removes all usages of coherent buffers for USB
control-request setup-packet buffers.  There's no good reason to
reserve coherent memory for these things; control requests are hardly
ever used in large quantity (the major exception is firmware
transfers, and they aren't time-critical).  Furthermore, only seven
drivers used it.  We might as well always use streaming DMA mappings
for setup-packet buffers, and remove some extra complexity from
usbcore.

The DMA-mapping portion of hcd.c is currently in flux.  A separate
patch will be submitted to remove support for URB_NO_SETUP_DMA_MAP
after everything else settles down.  The removal should go smoothly,
as by then nobody will be using it.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Stern
2010-03-05 15:10:17 -05:00
committed by Greg Kroah-Hartman
parent 749da5f82f
commit 0ede76fcec
13 changed files with 27 additions and 75 deletions
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18
drivers/usb/core/usb.c
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@ -775,7 +775,7 @@ EXPORT_SYMBOL_GPL(usb_free_coherent);
* @urb: urb whose transfer_buffer/setup_packet will be mapped
*
* Return value is either null (indicating no buffer could be mapped), or
* the parameter. URB_NO_TRANSFER_DMA_MAP and URB_NO_SETUP_DMA_MAP are
* the parameter. URB_NO_TRANSFER_DMA_MAP is
* added to urb->transfer_flags if the operation succeeds. If the device
* is connected to this system through a non-DMA controller, this operation
* always succeeds.
@ -803,17 +803,11 @@ struct urb *usb_buffer_map(struct urb *urb)
urb->transfer_buffer, urb->transfer_buffer_length,
usb_pipein(urb->pipe)
? DMA_FROM_DEVICE : DMA_TO_DEVICE);
if (usb_pipecontrol(urb->pipe))
urb->setup_dma = dma_map_single(controller,
urb->setup_packet,
sizeof(struct usb_ctrlrequest),
DMA_TO_DEVICE);
/* FIXME generic api broken like pci, can't report errors */
/* if (urb->transfer_dma == DMA_ADDR_INVALID) return 0; */
} else
urb->transfer_dma = ~0;
urb->transfer_flags |= (URB_NO_TRANSFER_DMA_MAP
| URB_NO_SETUP_DMA_MAP);
urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
return urb;
}
EXPORT_SYMBOL_GPL(usb_buffer_map);
@ -881,14 +875,8 @@ void usb_buffer_unmap(struct urb *urb)
urb->transfer_dma, urb->transfer_buffer_length,
usb_pipein(urb->pipe)
? DMA_FROM_DEVICE : DMA_TO_DEVICE);
if (usb_pipecontrol(urb->pipe))
dma_unmap_single(controller,
urb->setup_dma,
sizeof(struct usb_ctrlrequest),
DMA_TO_DEVICE);
}
urb->transfer_flags &= ~(URB_NO_TRANSFER_DMA_MAP
| URB_NO_SETUP_DMA_MAP);
urb->transfer_flags &= ~URB_NO_TRANSFER_DMA_MAP;
}
EXPORT_SYMBOL_GPL(usb_buffer_unmap);
#endif /* 0 */