USB: Support for submitting control URBs under xHCI.
commit6d65b78a093552fb42448480d4c66bf093a6d4cf
authorSarah Sharp <sarah.a.sharp@linux.intel.com>
Tue, 28 Apr 2009 02:57:50 +0000 (27 19:57 -0700)
committerGreg Kroah-Hartman <gregkh@suse.de>
Tue, 16 Jun 2009 04:44:49 +0000 (15 21:44 -0700)
tree38d5797b9cdd60421d6b28db225d34c9f2e56f6f
parent3ffbba9511b4148cbe1f6b6238686adaeaca8feb
USB: Support for submitting control URBs under xHCI.

Warn users of URB_NO_SETUP_DMA_MAP about xHCI behavior.

Device drivers can choose to DMA map the setup packet of a control transfer
before submitting the URB to the USB core.  Drivers then set the
URB_NO_SETUP_DMA_MAP and pass in the DMA memory address in setup_dma, instead of
providing a kernel address for setup_packet.  However, xHCI requires that the
setup packet be copied into an internal data structure, and we need a kernel
memory address pointer for that.  Warn users of URB_NO_SETUP_DMA_MAP that they
should provide a valid pointer for setup_packet, along with the DMA address.

FIXME:  I'm not entirely sure how to work around this in the xHCI driver
or USB core.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
include/linux/usb.h