Hi there.

My experience is different, namely that power on the hub is not essential 
to alleviate babble interrupts. I've seen lots of babble using a specific 
device (GNS-5890 ADS-B receiver from 
http://www.gns-gmbh.com/index.php?id=238&L=1) when hooked up directly to 
the BBB USB host port, but adding a non-powered hub or a non-powered 
USB-extender between device and host makes the babble interrupts that lock 
up the musb controller go away. Babble does still occur according to the 
kernel log but apparently no unrecoverable ones.

There has been some development on the musb kernel driver after the one 
referenced below by Ravi Babu, particularly George Cherian has done a 
series of patches implementing use of new babble prevention/diagnostic 
features in recent silicon revisions that seem to have fixed a lot of 
issues. The latest v7 of his "Add support for SW babble Control" series is 
at http://thread.gmane.org/gmane.linux.usb.general/111365. There is a lot 
of background information about babble in the threads of these patches for 
the curious and courageous of you ;).

How and if the patch has progressed into mainline or BBB kernels I havn't 
checked (but my guess is they haven't at all), and I haven't come around 
testingit myself yet because our production systems run fine with the 
hub-workaround.

Mikkel

Den onsdag den 21. januar 2015 kl. 08.30.19 UTC+1 skrev 
[email protected]:
>
> I can confirm, that the issue can be solved by inserting an active USB hub 
> (externally powered).
> Am Freitag, 12. Dezember 2014 14:52:50 UTC+1 schrieb [email protected]
> :
>>
>> Try to use an USB hub with external power. This solved my problem.
>> On Saturday, August 9, 2014 4:38:14 AM UTC+2, [email protected] wrote:
>>>
>>> Anyone know about the patch referenced here? Or any other workaround to 
>>> make USB usable on BBB?
>>>
>>> http://comments.gmane.org/gmane.linux.usb.general/87138 
>>> <http://www.google.com/url?q=http%3A%2F%2Fcomments.gmane.org%2Fgmane.linux.usb.general%2F87138&sa=D&sntz=1&usg=AFQjCNE5-dk-0FfHzNfrrjrTQdcE7WfpCQ>
>>>
>>

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