strange usb errors


I have a few weird USB related errors.

Hardware: beagleboard rev C2.
OS: 2.6.28 (angstrom, r15 version)

If I connect my pvrusb2 controller directly to the usb host port the
device works as expected.

However if I connect the device through a (powered) usb hub, the
device does not work.
dmesg says:

usb 1-2.2: new high speed USB device using ehci-omap and address 5
usb 1-2.2: configuration #1 chosen from 1 choice
usb 1-2.2: firmware: requesting v4l-pvrusb2-29xxx-01.fw
pvrusb2: Device microcontroller firmware (re)loaded; it should now
reset and reconnect.

but it does not reconnect.
I would not expect a usb hub to have such an effect. Note that the hub
is working and that devices like an ethernet dongle and a bluetooth
dongle work like a charm with the hub.

I also saw a fw load problem with the hardware (same system).

one more issue, same hw/sw;

If I connect my webcam (pwc driver) through the hub on the usb host port I get:
pwc: isoc_init() submit_urb 0 failed with error -28

On the otg port (again through a hub) there are some aretefacts (as
reported before)

directly connecting the cam to the usb host port does not work (guess
it is a 1.1 device which is not supported on the beagle host port).


The EHCI port is ONLY High speed. It cannot support Full or Low speed devices.


I am aware that the EHCI port is only high speed. That is why I wrote
"(guess it is a 1.1 device which is not supported on the beagle host
actually meanwhile I verified things and indeed it is a 1.1 device
(full speed).
Btw the cam is a Philips PCVC680K


I was replying to the list so others would understand what was meant by not supporting 1.1 devices. I was confident you understood the issue. As you know, only a few peoplw have experience witht the EHCI port on Beagle, and with it about to hit the store shelf, I took the opportunity to do a little “advance” work.


I'm seeing the same problems with webcam (Logitech 4000) data
corruption. I've been testing with both Rev B6 and C2 Beagleboards and
a variety of kernels and distros but the behaviour is consistent.
However, on Rev C2, if the USB to Ethernet (Trendnet TU2-ET100) is
moved from the OTG port connected hub to the EHCI port connected hub,
everything works perfectly (as noted above, it's not possible to test
both webcam and USB on the EHCI hub due to the pwc error on that

The application I am running to test this streams the webcam data over
the Ethernet connection. Consequently, if the webcam and Ethernet are
on the same port, there are a serious amount of asynchronous transfers
going on. There was an errata on earlier OMAP silicon in this area but
I assume that was fixed in the current silicon rev on the C2 board.

Incidentally, if both webcam and Ethernet connection are on the OTG
port hub, I also get these errors from time to time in addition to the
image errors:

eth0: asix_rx_ifxup() Bad Header length


eth0: asix_rx_fixup() Bad Rx length xxxxx

This suggests that it is fundamental to the USB port driver, not
specific to the webcam driver. Eventually (after maybe 3 hours) the
Ethernet link dies

Is there any more information on what is happening here?