Re: [Alsa-devel] Problems with Hercules DJ Console and the usb-audio driver
On Thu, Sep 15, 2005 at 02:10:41PM -0400, Lee Revell wrote:
> On Thu, 2005-09-15 at 14:13 +0200, Clemens Ladisch wrote:
> > Horms wrote:
> > > On Wed, Sep 14, 2005 at 03:29:13PM +0200, Daniel Svensson wrote:
> > > > CONFIG_USB_BANDWIDTH is enabled by default in the debian kernel. Could
> > > > this be changed? According to the alsa developer who helped me debug the
> > > > problem with my usb soundcard CONFIG_USB_BANDWIDTH should be disabled.
> > > > The original email is forwarded here:
> > >
> > > That sounds fair enough to me, as long there are no objections
> > > from the rest of the kernel-team.
> > >
> > > Clemens, could you provide a little more information on
> > > the problems that CONFIG_USB_BANDWIDTH causes?
> >
> > The code that implements it computes wrong values for the bandwidth
> > utilization. This doesn't seem to matter much for full speed stereo
> > devices, but we have several bug reports for multichannel and/or high
> > speed devices where usb_submit_urb() incorrectly returns -ENOSPC
> > errors.
> >
> > The comment above the usb_check_bandwidth() function in hcd.c lists
> > several of the known bugs.
> >
> > Perhaps CONFIG_USB_BANDWIDTH should have been marked BROKEN instead of
> > just EXPERIMENTAL.
Thanks for the clarification.
> Has this been reported upstream? Possibly the USB maintainers don't
> know that this is causing real problems for users.
That would be a good idea if it hasn't been done,
but I know nought about this sistuation, so my
comments are close to worthless.
--
Horms
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