USB: remove uses of URB_NO_SETUP_DMA_MAP
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>
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