From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stefan Richter <stefanr@s5r6.in-berlin.de>
Subject: Re: [PATCH 0/5] ALSA: firewire-tascam: add MIDI
	functionality
Date: Wed, 14 Oct 2015 00:20:51 +0200
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To: Jonathan Woithe <jwoithe@just42.net>
Cc: tiwai@suse.de, alsa-devel@alsa-project.org, clemens@ladisch.de, ffado-devel@lists.sf.net, Takashi Sakamoto <o-takashi@sakamocchi.jp>
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On Oct 13 Jonathan Woithe wrote:
> for cases like MOTU, where mixer control setting updates
> are pushed to the computer by the device in response to front panel actions,
> there will be a need for userspace to somehow tap into this flow.  Userspace
> could not gain access to the iso stream because the kernel will have control
> over that.  Or can userspace tap into iso streams that have been initiated
> by the kernel (that is surprising to me if it's true).

Indeed we do not have support for multiple local listeners on the same
stream.  (firewire-core supports multiple listeners for FCP reception, but
this is a simpler case in several respects.)

I guess getting MOTU status out to userspace could work by having the
audio driver extract the data from the stream and push it as a new type of
event of the <sound/firewire.h> API through the ALSA hwdep interface.

(Apologies for going somewhat offtopic.)
-- 
Stefan Richter
-=====-===== =-=- -==-=
http://arcgraph.de/sr/