Clearing stalls: usbd_xfer_set_stall vs usbd_do_clear_stall_callback

Hans Petter Selasky hselasky at c2i.net
Fri May 20 11:45:47 UTC 2011


On Thursday 05 May 2011 10:09:55 Hans Petter Selasky wrote:
> On Thursday 05 May 2011 09:15:09 Trevor Blackwell wrote:
> > 8.2-STABLE. I'm willing to run whatever.
> > 
> > I suspect the problem I'm having is the same as this:
> > http://kerneltrap.org/mailarchive/linux-usb/2009/5/15/5761363
> > 
> > I can manually kick it out of the wedged state by sending a RESET_TT
> > transaction to the hub with usbconfig -d ugen1.3 do_request 0x23 0x09
> > 0x0000 0x0001 0
> > 
> >   (UT_WRITE_CLASS_OTHER, UR_RESET_TT)
> > 
> > I'm working on adding code to do this. My current hack is to do it from
> > uhub_explore. When my driver tries to do a clear-stall and gets a timeout
> > error from the clear-stall, it sets a flag on the parent_hs_hub to
> > request a RESET_TT. uhub_explore notices the flag and does it.
> > 
> > Possibly I could also add it to usb_do_clear_stall_callback, but I don't
> > think I can call usb_do_request from inside a callback.
> > 
> > Any suggestions?
> 
> Hi,
> 
> I think it is best to do this from the root HUB thread, then the operation
> gets properly serialised. Then the clear-stalls requests will simply be
> pending until normal operation is established.
> 
> Could a control endpoint timeout in general imply that the parent High
> Speed HUB, if any, should be reset?
> 
> --HPS

Any updates on this issue?

--HPS


More information about the freebsd-usb mailing list