From mboxrd@z Thu Jan  1 00:00:00 1970
From: Takashi Iwai <tiwai@suse.de>
Subject: Re: [RFC][PATCH 0/8] ALSA: dice: constrain PCM
	substreams to current sampling transfer frequency
Date: Wed, 18 Nov 2015 15:13:25 +0100
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To: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Cc: alsa-devel@alsa-project.org, clemens@ladisch.de, ffado-devel@lists.sf.net
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On Sun, 15 Nov 2015 10:25:28 +0100,
Takashi Sakamoto wrote:
> 
> Hi,
> 
> This patchset adds a constrain to ALSA dice driver to start PCM
> substreams and AMDTP packet transferring just at current sampling
> transfer frequency.
> 
> Dice hardware doesn't allow drivers to get supported combinations
> between sampling rate and PCM channels. ALSA dice driver should follow
> to the hardware design, though current ALSA driver has some
> over-specifications. As a result, the driver has several issue and
> brings inconvenience to users.
> 
> This patchset consists of two parts:
>  * 01-05: to add constrain to current sampling transfer frequency and related
> 	  code cleanup
>  * 06-08: to ensure and stabilize AMDTP packet transmission
> 
> As a result, userspace applications can request PCM substreams at current
> sampling transfer frequency. Therefore, when users want to start PCM
> substreams at different rate, they should set the rate in advance by the
> other ways (i.e. ffado-dbus-server/ffado-mixer).

This sounds rather like a step backward.  Why can't the driver set the
rate if it's the only first and exclusive user?


thanks,

Takashi