Functionality of pcm_notify in snd-aloop?

[Jaroslav Kysela]

Dne 26. 03. 20 v 18:19 Pavel Hofman napsal(a):
> Hi,
> 
> Please how is the module params pcm_notify supposed to be used, to do
> what the documentation says: Break capture when PCM format/rate/channels
> changes?
> 
> Breaking capture side operation when the playback side changes the
> params is very useful, but I cannot find a way to use this param
> properly. When the capture side is open, the playback side cannot use a
> different parameter than the one currently used by the capture side (the
> configuration space is limited)

Really? Then it's a bug introduced by the last changes.

If you look to sources:

       if (get_notify(dpcm))
                 runtime->hw = loopback_pcm_hardware;
         else
                 runtime->hw = cable->hw;

And:

       if (!(cable->valid & ~(1 << substream->stream)) ||
             (get_setup(dpcm)->notify &&
              substream->stream == SNDRV_PCM_STREAM_PLAYBACK))
                 params_change(substream);

So the functionality should be there.

				Jaroslav

-- 
Jaroslav Kysela <perex at perex.cz>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.