[alsa-devel] AD1988B: ALSA doesn't use dmix automatically

Takashi Iwai tiwai at suse.de
Mon Mar 17 12:45:20 CET 2008

At Sat, 15 Mar 2008 23:48:52 -0300,
Dâniel Fraga wrote:
> ALSA 1.0.15
> http://alsa.opensrc.org/index.php/Dmix
> NOTE: For ALSA 1.0.9rc2 and higher you don't need to setup dmix. Dmix
> is enabled as default for soundcards which don't support hw mixing.
> 	So why if I try to play 2 sounds at the same time, the second
> one complains the "resource is busy"? Shouldn't it detect that AD1988B
> can't do hardware mixing and use dmix automatically? 

It does as long as the app uses the "default" PCM.  The dmix isn't
forced to be applied.  The exclusive hardware access is still
available by opening the PCM as "hw", "plughw" and etc.  So, if any
apps access exclusively, others will suffer.


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