Re: USB Audio/Midiman - partial success

[Takashi Iwai <tiwai@suse.de>]

At Thu, 26 Sep 2002 09:47:50 +0200 (METDST),
Clemens Ladisch wrote:
> 
> Fedor G. Pikus wrote:
> > On Wed, 25 Sep 2002, Takashi Iwai wrote:
> > > At Tue, 24 Sep 2002 20:03:54 -0700 (PDT),
> > > Fedor G. Pikus <fedorp@wv.mentorg.com> wrote:
> > > >
> > > > > then the complete callback is called properly but likely
> > > > > snd_pcm_period_elapsed() is not called.
> > > >
> > > > That's right, it's not called:
> > > > for (i = 0; i < urb->number_of_packets; i++) {
> > > >         cp = (unsigned char *)urb->transfer_buffer + urb->iso_frame_desc[i].offset;
> > > >         if (urb->iso_frame_desc[i].status) /* active? hmm, skip this */
> > > >                 continue;
> > >
> > > could you check what value is stored in the status field?
> > > i guess some negative value, which represents an error.
> > Always -75.
> 
> -75 = -EOVERFLOW = babble
> 
> I think this indicates that the device sends more data than the driver
> expects. Probably the transfer buffer size is calculated for some lower
> sample rate?

it can be.

what shows /proc/asound/card0/stream* if the corresponding pcm is
running?  this will show the current interface and altset.

also, the transferred size for each packet is defined as
subs->curpacksize (in bytes) and subs->curframesize (in frames).
please check these values via printk.


ciao,

Takashi


-------------------------------------------------------
This sf.net email is sponsored by:ThinkGeek
Welcome to geek heaven.
http://thinkgeek.com/sf