From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: [PATCH 2/3] ALSA: snd-usb-caiaq: set up internal
 sample pointer positions in trigger callback
Date: Fri, 10 Sep 2010 09:27:48 +0200
Message-ID: <4C89DDF4.8030200@ladisch.de>
References: <1284090901-4533-1-git-send-email-daniel@caiaq.de>
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To: Daniel Mack <daniel@caiaq.de>
Cc: tiwai@suse.de, alsa-devel@alsa-project.org
List-Id: alsa-devel@alsa-project.org

Daniel Mack wrote:
> Calling prepare() on a stream which is already active

... would be a bug; snd_pcm_pre_prepare() in sound/core/pcm_native.c
should prevent this.  Why do you feel the need for this patch?

> shouldn't touch the sample pointer positions. This code belongs into
> the trigger callback, so move it there.

The trigger callback should execute as fast as possible; any
initialization that isn't need to directly start the stream should go
into the prepare callback.


Regards,
Clemens