On Fri, Jan 13, 2012 at 09:51:47PM +0100, Sebastian Andrzej Siewior wrote: > dummy_hcd provides (alloc|free)_stream() callbacks but there are not > doing anything. The transfer side also lacks matching of streams. This > patch changes this and implements stream allocation / de-allocation > support and proper urb <=> req matching. > The UDC side exposes a limit of 16 streams. DWC3, the only USB3 UDC has > no limitations in this regard except that it _needs_ to know that > streams will be used at the ep_enable time. At the host side, there is > no real limit either: XHCI can allocate any number of streams as long as > it does not run out of memory. The UAS gadget currently requests 16 > streams and the UAS host side fallbacks from the requested 256 down to > 16 which is fine. > From the UASP point of view (the only specified user), the number of > used streams does not really matter. The only limitation is that the > host may not use a higher stream than the gadget requested and can deal > with. > > The dummy stream support has been modelled after current UAS + XHCI + > DWC3 + UASP usage which helps me testing: > - the device announces that each ep supports 16 streams (even it could > more than that). > - the device side looks into Companion descriptor at ep_enable time and > enables them according to it. > - the host side tries to enable the requested number of streams but the > upper limit is the Comanion descriptor. None (zero streams) is an > error condition, less is okay. > > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> applied, thanks -- balbi
Attachment:
signature.asc
Description: Digital signature
