Trouble with EHCI controller and USB Flash Disk.

Doug White dwhite at
Mon Apr 26 18:27:01 PDT 2004

On Wed, 21 Apr 2004, Julian Elischer wrote:

> > > I have problems with mine USB2.0 Mobile Disk III and EHCI controller.
> > > (
> > >
> > > When I try to use EHCI controller, my system finds out
> > > the device /dev/da0, but does not find out the
> > > device /dev/da0s1.
> > >
> > > With UHCI controller no problem.
> >
> > Since it works with UHCI, it's likely an EHCI problem.  Unfortunately, I
> > don't know much about EHCI so I'm moving this to -current.
> The ehci driver has quite a few problems.
> It workd in some cases but not in others.
> I have not yet isolated what the defining factor is.

I think EHCI has a tendency to drop transactions. I got umass really
confused a few weeks back by attaching one usb key to ehci and a low key
to uhci and trying to do stuff on both keys at once.  The transaction
sequence #s got off-by-one and never recovered (due to a bug in umass),
but the txn shouldn't have disappeared in the first place.

Doug White                    |  FreeBSD: The Power to Serve
dwhite at          |

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