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From: Clemens Ladisch <clemens@ladisch.de>
To: Adrian Knoth <adi@drcomp.erfurt.thur.de>
Cc: alsa-devel@alsa-project.org,
	Andre Schramm <andre.schramm@iosono-sound.com>
Subject: Re: Complex hw buffer with MMAP_COMPLEX?
Date: Tue, 09 Oct 2012 15:49:32 +0200	[thread overview]
Message-ID: <50742B6C.9080601@ladisch.de> (raw)
In-Reply-To: <50742405.9070201@drcomp.erfurt.thur.de>

Adrian Knoth wrote:
> That is, we're dealing with 25 (or 26 for output) interleaved streams
> with two or eight channels each.
>
> How could we represent such a layout in ALSA, that is, how are we
> talking to userspace? Would one create subdevices and rejoin them via
> plughw?

Is it possible to start/stop the streams independently?
If yes, this might be useful.

(And subdevices are usually used for streams that are mixed together.)

> Or use MMAP_COMPLEX and then let every application deal with it
> on its own?

Alsa-lib can automatically convert this.  Applications that insist
on using hw devices have to deal with it (Jack does).


Regards,
Clemens

  reply	other threads:[~2012-10-09 13:49 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-10-09 13:17 Complex hw buffer with MMAP_COMPLEX? Adrian Knoth
2012-10-09 13:49 ` Clemens Ladisch [this message]
2012-10-09 14:09   ` Adrian Knoth
2012-10-09 14:19     ` Takashi Iwai

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