[alsa-devel] Flash Plugin & IO Plug: Async interface not implemented?

[Takashi Iwai]

At Mon, 7 Apr 2008 17:49:26 +0300,
Alexander Indenbaum wrote:
> 
> Hello,
> 
> I'm trying to integrate Firefox Flash plugin with ASLA IO plug driver
> for proprietary hardware.
> 
> I've found out that Flash Plugin ASLA client side (sources could be
> found at http://labs.adobe.com/wiki/index.php/Flash_Player:Additional_Interface_Support_for_Linux)
> is incompatible with IO Plug.

Oh, it's a good finding.  Thanks for the pointer.


> The reason is that during initialization
> Flash Plugin calls snd_async_add_pcm_handler() which always return
> -ENOSYS out of snd_pcm_ioplug_async(). This error causes Flash Plugin
> ALSA client code to fail.
> 
> Is there a good reason why snd_pcm_ioplug_async() unconditionally
> return  -ENOSYS?
> Is it possible to implement  IO Plug async interface?

Well, this is simply because I haven't supposed that the async
interface is ever used by such apps.  The async feature is pretty
system-specific and it wouldn't work with the strict POSIX
implementation.  It practically works right now, though :)

So, I'm pretty open for any implementation of this if the user-space
driver can provide any functionality.  Most likely we need to add a
new callback, so the ABI would change.  But, as long as the backward
compatibility is kept, I'm for any addition.


thanks,

Takashi