Re: status of USB on omap35xx ?

[Tony Lindgren <tony@atomide.com>]

* Steve Sakoman <sakoman@gmail.com> [081210 15:02]:
> On Wed, Dec 10, 2008 at 10:28 AM, David Brownell <david-b@pacbell.net> wrote:
> > The OTG link is in usable shape, but the EHCI one isn't.
> >
> >
> > On Wednesday 10 December 2008, Felipe Balbi wrote:
> >> >
> >> > What are the issues ?
> >
> > I have a prototype Overo and one issue there is that the
> > GPIO to let the EHCI port supply VBUS power isn't hooked
> > up!  I know how to modify that board, but somehow that
> > keeps slipping off my radar ... :)
> 
> That issue is fixed on the shipping "Summit" boards.
> 
> > I don't know the details, but the big problem with EHCI
> > on OMAP3 is evidently some kind of silicon issue that
> > shows up through the transceiver hookup and prevents the
> > link from being reliable.  I'm told that some boards using
> > that without a transceiver -- for on-board communication,
> > not for an external link -- have been successful.
> >
> > Folk at TI were looking at those issues; I don't know if
> > they've been resolved yet, e.g. in the ES 3.0 silicon.
> 
> I see that Vikram has responded to this already.
> 
> >> It think it still has a problem during probe. If you read the driver
> >> you'll see there are some infinite while loops without timeout actions.
> >> And one of them is looping forever due to clock issues.
> >
> > That's a newish problem, but is not -- from what I've
> > been told -- the Real Issue with EHCI on OMAP3.
> 
> This problem has actually been around since 2.6.27.
> 
> Prior to that, the EHCI port "sort of" worked - but not super
> reliably.  It would enumerate devices on the bus, but then die
> randomly afterwards.
> 
> Since somewhere during the 2.6.27 time frame we've been suffering from
> the infinite loop at boot problem.
> 
> I patched around the loop that seemed to be causing the issue, but
> didn't have great success getting back to even the "sort of" working
> state.
> 
> I am far from being a USB expert, so the messages in the log don't
> mean a whole lot to me :-)

Can you please post whatever patches you need to apply to make it work
occasionally so others can also look at the issue?

Thanks,

Tony


> ehci-omap ehci-omap.0: USB 2.0 started, EHCI 1.00
> usb usb2: configuration #1 chosen from 1 choice
> hub 2-0:1.0: USB hub found
> hub 2-0:1.0: 3 ports detected
> usb usb2: New USB device found, idVendor=1d6b, idProduct=0002
> usb usb2: New USB device strings: Mfr=3, Product=2, SerialNumber=1
> usb usb2: Product: OMAP-EHCI Host Controller
> usb usb2: Manufacturer: Linux 2.6.28-rc7-omap1 ehci_hcd
> usb usb2: SerialNumber: ehci-omap.0
> <snip>
> usb usb2: bus auto-suspend
> usb usb2: uevent
> usb 2-0:1.0: uevent
> <snip>
> usb usb2: usb auto-resume
> usb usb2: bus auto-suspend
> 
> Steve
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