[LAD] Call for testing (final): ALSA driver for some firewire devices

Takashi Sakamoto o-takashi at sakamocchi.jp
Mon May 5 20:46:21 UTC 2014

Hi Matt,

(May 06 2014 03:21), M Murdock wrote:
> ffado-dbus-server.out
> <http://linux-audio.4202.n7.nabble.com/file/n90825/ffado-dbus-server.out>

As long as I can see this log, 'ffado-mixer' correctly communicate with 

> *FFADO*: version.h shows "PACKAGE_VERSION 2.1.9999-2504"
> svn log --limit 1 shows:
> ------------------------------------------------------------------------
> r2504 | jwoithe | 2014-05-03 08:57:38 -0400 (Sat, 03 May 2014) | 1 line
> README: some initial editting of device status information in preparation
> for the release of FFADO 2.2
> ------------------------------------------------------------------------

OK. It's based on r2504. Currently we, FFADO developers parepare for new 
FFADO version and this revision includes related modification for README.

> *ALSA*: git diff HEAD^ HEAD shows the following
> diff --git a/sound/firewire/amdtp.c b/sound/firewire/amdtp.c
> index e573f25..29291e4 100644
> --- a/sound/firewire/amdtp.c
> +++ b/sound/firewire/amdtp.c
> @@ -418,7 +418,7 @@ static void amdtp_write_s16(struct amdtp_stream *s,

I expected you to run 'git show' and just show me commit hash. But 
according to the 'index' field in this output, I can see HEAD in your 
local repository is based on this:
firewire-lib: Fix wrong label for 16 bits Raw Audio data 

I can understand you work with recent sources.

> I followed your request for logging ffado-dbus-server output.  Attached is
> the debug file captured with the following:
> ffado-dbus-server -v 6 &> /tmp/ffado-dbus-server.out
> I started ffado-mixer, played with most of the analoge input sliders,
> auxiliary sliders, output sliders, and muted/unmuted channels.  I also
> manually adjusted some of the faders on the ProjectMix.  The
> ffado-dbus-server was then killed.
> I was able to confirm that the headphone volume works through the ProjectMix
> hardware when listening to random noise.

So in this time, ffado-mixer works fine. I think you failed because 
there were several processes of 'ffado-dbus-server'. Usually just one 
process can execute I/Os between devices so your 'ffado-mixer' 
communicated to one of these processes which cannot execute I/Os.

> I was able to record and to play back using aplay and arecord and the
> "plughw:ProjectMix" device.  This is great!  I didn't see any logs in syslog
> for ALSA.
> I admit that I don't know the difference between "hw:ProjectMix" and
> "plughw:ProjectMix".  For instance, how should I start jackd (I use
> qjackctl).  Should I use the alsa or firewire driver in qjackctl?  Which
> device should I specify, hw:ProjectMix or plughw:ProjectMix?

Use hw:ProjectMix for jackd. jackd can automatically adjust the number 
of PCM channels, on the other hand aplay/arecord can't.

>> Simple mixer control 'Clock Source',0
>> Simple mixer control 'Digital Input Interface',0
>> Simple mixer control 'Digital Output Interface',0
>> Simple mixer control 'Sync Status',0
> I was unable to find out where or how to change the PCM channels.  alsamixer
> exposes options for clock source, digital input interface (S/PDIF or ADAT)
> and digital output interface (S/PDIF or ADAT).  I thought the PCM interfaces
> would refer to the physical input and output channels (analogue streams)
> available on the ProjectMix.

I meant the 'Digital Input Interface' and 'Digital Output Interface' as 
'digital interfaces for input/output'. They're not 'PCM interface'.

When you switch these controls between 'S/PDIF' and 'ADAT', you can see 
the differences of PCM channels which your jackd recognizes.

> I would like to test the MIDI functionality, but I believe my jackd
> configuration needs attention first.  Insight into how to configure jackd
> properly would be much appreciated.

Try to execute in terminal:
$ jackd -r -d alsa -d hw:ProjectMix -r 48000

If your system is configured to authenticate your account for 'rtprio' 
priviledge, this line is also available:
$ jackd -R -P 89 -d alsa -d hw:ProjectMix -r 48000


Takashi Sakamoto
o-takashi at sakamocchi.jp

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