RE: PROBLEM: USB isochronous urb leak on EHCI driver

[Michael Tessier <michael.tessier@axiontech.ca>]

> > > > That is interresting, however, I have an older kernel running an=20
> > > > OHCI driver which is able to handle 4 codecs. Same usb hardware=20
> > > > (codecs and hub), but older kernel on a different CPU, with much=20
> > > > less power. This makes me believe that there's a solution to make i=
t work...
> > >=20
> > > Of course there is: Install an OHCI host controller and use it to dri=
ve your codecs.  It should work fine.

What do you mean by that? The host controller is embedded in the i.MX CPU..=
.
Changing the CPU is not really an option to me. Unless I am missing
something?

> > >=20
> > > The periodic scheduling algorithm for OHCI is very different from the=
 algorithm for EHCI.
> >=20
> > According to your knowledge, how much time would you think it takes to=
=20
> > change the EHCI driver with an OHCI one?
>
> I don't understand the question.
>
> >  And can you tell if the OHCI driver
> > will work on my hardware given that the Host controller of the i.MX512=
=20
> > is a USB2.0 host controller? (OHCI was implemented for USB 1.x from=20
> > what I
> > understand)
>
> The OHCI driver works with OHCI hardware and the EHCI driver works with E=
HCI hardware.  OHCI is USB-1.1 and EHCI is USB-2.  They are not interchange=
able.

That was what I thought first...

>
> > I tried to do so several days ago with the built-in configurator (I am=
=20
> > using "ltib"), but the configurator does not allow selecting the OHCI=20
> > driver; I tried manually but it turned into compiler errors...
>
> It looks like the configurator is smart; it won't let you select the wron=
g driver for your hardware.
>
> Alan Stern