On Thu, Aug 01, 2013 at 10:15:51AM +0200, Oliver Neukum wrote: > On Thu, 2013-08-01 at 15:30 +0800, Greg Kroah-Hartman wrote: > > On Wed, Jul 31, 2013 at 09:40:26AM -0700, Sarah Sharp wrote: > > > On Wed, Jul 31, 2013 at 06:51:47PM +0800, Ming Lei wrote: > > > > This patch marks all xHCI controllers as no_sg_limit since > > > > xHCI supports building packet from discontinuous buffers. > > > > > > > > Cc: Sarah Sharp <sarah.a.sh...@linux.intel.com> > > > > Signed-off-by: Ming Lei <ming....@canonical.com> > > > > > > Acked-by: Sarah Sharp <sarah.a.sh...@linux.intel.com> > > > > Is it a requirement that all xhci controllers support sg? I know we are > > starting to see other controllers (the platform code?) so would they > > need to support this as well? > > The way XHCI describes transfers allows them to be arbitrary.
Yes, Oliver is right. The xHCI host can handle arbitrary length buffers chained together into one transfer, and now that we have the xHCI driver ring expansion code in place, we should be able to make them as long as the USB core will allow. Sarah Sharp -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
