On Fri, 14 Oct 2005, David Brownell wrote: > > > > We will still have the problem that the HCDs don't have access to the > > > > spinlock that protects the queue pointers. I suppose the spinlock could > > > > be EXPORTed. > > > > > > That problem is ... what? Â Exporting that lock would imply there's some > > > good reason for code other than usbcore to use it. Â I haven't seen one. > > > > maybe one of the reasons is that you use ep's queue without holding > > any usbcore's locks in sl811 hcd... > > Usbcore only appends to the tail, except for giveback(). The HCD only > reads its head, or calls giveback(). Is there some situation where > either would see (or create) an inconsistency?
This may be true for sl811-hcd or Franck's driver, but it won't be true for uhci-hcd. There will be times when I have to scan through the entire queue, looking for URBs which have been unlinked and are waiting to be given back. Alan Stern ------------------------------------------------------- This SF.Net email is sponsored by: Power Architecture Resource Center: Free content, downloads, discussions, and more. http://solutions.newsforge.com/ibmarch.tmpl _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
