USB Disconnect in Beagleboard C4 after suspend resume

I am using Angstrom in my beagleboard. Kernel is taken from linux-omap-
pm 2.6.35-rc3.

I have connected a USB Ethernet to the board. The board is powered via
5V port.

The Ethernet port stops working If I suspend and resume my

[ 1103.120849] PM: resume of devices complete after 387.786 msecs

[ 1103.376251] Restarting tasks ...

[ 1103.379669] usb 1-2: USB disconnect, address 2

[ 1103.411315] done.

[ 1103.445892] usb 1-2.4: USB disconnect, address 3

[ 1103.450836] asix 1-2.4:1.0: eth0: unregister 'asix' usb-ehci-omap.
0-2.4, ASIX AX88772 USB 2.0 Ethernet

It doesnot work even if I disconnect and reconnect the USB. I think
some problem with EHCI.
Is there any workaround for this issue? Any suggestions will be highly

Take a look at the erratta on the processor. Suspend and resume does not work on the EHCI port. You can also do a search on the email list on this topic as well.


Hello Gerald, Thanks for your time.

I went through erratta and the group. This problem seems to happen
with Beagleboard C3. But mine is C4.
Please correct me if I am wrong.


I am not talking about the board errata. I am talking about the processor errata. Suspend and resume is not supported on the processor.


Here is the link.


Hello Gerald,

Thanks a lot for the link. The workarounds looks very complex to me.

Is this issue fixed in Beagleboard xM?


It is my understanding that the next revision of silicon will take care of that, but I have no confirmation of that. The Beagleboard-xM rev C will have the latest silicon.