Re: C-Media / usb device bug ?

[Pablo Yaggi <pyaggi@alsurdelsur.com>]

On Tuesday 19 September 2006 03:36, Clemens Ladisch wrote:
> Pablo Yaggi wrote:
> >  I'm working in a multi-capture application with alsa and i discovered
> > if i attach two "c-media usb headphone set" adapters to an usb hub which
> > is attached to my computer when i try to read from the two devices the
> > first one read (also open) errors with (-77) bad file descriptor status
> > and the other one keep working. When i attach the two devices directly to
> > the usb connectors (without hub) all works fine, the two devices can be
> > read at the same time.
> 
> What kernel version are you using?
> 
> The EHCI transaction translator code (which is responsible for moving
> audio data through an high speed hub) got a bugfix in 2.6.17, but still
> artificially limits the bandwidth.  It will be rewritten in 2.6.18.
> 
> 
> HTH
> Clemens
> 

I tested it on 2.6.15, 2.6.16 and 2.6.17,
so you think the problem is EHCI ?  is there anyway to check it ?
is it yet in rewriting process ? 
Thank's
Pablo

-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys -- and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV