[pulseaudio-discuss] [PATCH] alsa: reread configuration when opening new devices

[Alexander E. Patrakov]

22.05.2016 02:03, Alexander E. Patrakov wrote:
> If a card has been hot-plugged after pulseaudio start, alsa-lib still has
> old configuration in memory, which doesn't have PCM definitions for the
> new card. Thus, this error appears, and the device doesn't work:
>
> I: [pulseaudio] (alsa-lib)confmisc.c: Unable to find definition 'cards.USB-Audio.pcm.front.0:CARD=0'
> I: [pulseaudio] (alsa-lib)conf.c: function snd_func_refer returned error: No such file or directory
> I: [pulseaudio] (alsa-lib)conf.c: Evaluate error: No such file or directory
> I: [pulseaudio] (alsa-lib)pcm.c: Unknown PCM front:0
> I: [pulseaudio] alsa-util.c: Error opening PCM device front:0: No such file or directory
>
> The snd_config_update_free_global() function makes alsa-lib forget any
> cached configuration and reparse all PCM definitions from scratch next
> time it is told to open anything.
>
> The trick has been copied from Phonon.
>
> Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=54029
> Signed-off-by: Alexander E. Patrakov <patrakov at gmail.com>

Obviously, the proposed patch is invalid if PulseAudio calls 
snd_something_open() from more than one thread. I don't know if this is 
the case.

-- 
Alexander E. Patrakov