On Mon, Jul 01, 2002, David Brownell <[EMAIL PROTECTED]> wrote: > > - Given the basic similarities between all that hardware (the only > > "big" thing that needs to differ much is scanning the HC lists > > to collect finished transactions), I think both UHCIs can very > > likely be trimmed down further: the known differences can't > > account for that much of a size difference. (EHCI is a bit more > > complex than UHCI ... by rights, it should be the fattest HCD! > > I heard MSFT's is over 100KBytes ... :) > > Further comment on this point: both the UHCIs could be made > simpler if they only used a single lock internally, and had > less variety in routines to add and remove TDs from QHs. > (The rule of thumb on locking is of course to avoid using > such fine grained locking, since it rarely pays.) > > The only relative complication I see there is the fact UHCI > drivers (not hardware) must maintain the data toggle state, > which complicates queueing new bulk (and eventually interrupt) > urbs given errors and (as recently reported :) unlinks. In > both cases the simpler (and more consistent) solution is to > purge all queued URBs at the same time.
While I agree some of the locking can be made simpler, it can't be reduced to 1 lock. JE ------------------------------------------------------- Sponsored by: ThinkGeek at http://www.ThinkGeek.com/ _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
