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From: Clemens Ladisch <clemens@ladisch.de>
To: "Dominic Sacré" <dominic.sacre@gmx.de>, alsa-devel@alsa-project.org
Subject: Re: snd-fireworks requires larger period sizes than FFADO
Date: Mon, 23 Nov 2015 11:40:56 +0100	[thread overview]
Message-ID: <5652ED38.6080409@ladisch.de> (raw)
In-Reply-To: <56510A5F.4080004@gmx.de>

Dominic Sacré wrote:
> I'm trying to use an Echo AudioFire 4 with the snd-fireworks driver.
> With FFADO the device works reasonably well at a period size of
> 64 samples (on a PREEMPT_RT kernel), whereas with snd-fireworks the
> lowest possible period size seems to be 256 samples.
>
> The lowest achievable analog roundtrip latency seems to be around 19ms
> (at 2x256 frames), as opposed to 8.3ms with FFADO (at 2x64). Are there
> any known limitations of the snd-fireworks driver in this regard?

At the moment, the driver uses a minimum period size of 5 ms.

You could try reducing INTERRUPT_INTERVAL and the parameter to
snd_pcm_hw_constraint_minmax() in sound/firewire/amdtp-stream.c, and
recompiling the driver.


Regards,
Clemens

  reply	other threads:[~2015-11-23 10:40 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-11-22  0:20 snd-fireworks requires larger period sizes than FFADO Dominic Sacré
2015-11-23 10:40 ` Clemens Ladisch [this message]
2015-12-01 14:31   ` Stefan Richter
2015-12-01 17:15     ` Clemens Ladisch
2015-12-02  0:31     ` Takashi Sakamoto

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