From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jaroslav Kysela <perex@perex.cz>
Subject: Re: [PATCH 2/2] add API to allow disabling period
 interrupt
Date: Tue, 2 Nov 2010 09:38:10 +0100 (CET)
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To: Clemens Ladisch <clemens@ladisch.de>
Cc: Pierre-Louis Bossart <bossart.nospam@gmail.com>, alsa-devel@alsa-project.org, Pierre-Louis Bossart <pierre-louis.bossart@intel.com>
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On Tue, 2 Nov 2010, Clemens Ladisch wrote:

>> + * It is not allowed to call this function when given configuration is not exactly one.
>> ...
>> +int snd_pcm_hw_params_can_disable_period_irq(const snd_pcm_hw_params_t *params)
>
> This function is useless because it cannot be called before
> snd_pcm_hw_params_set_period_irq().

I don't think so. The info bits from the driver are used in this check 
which are read-only.

>> + * This function should be called only on devices where
>> + * #snd_pcm_hw_params_can_disable_period_irq() returns true. (too late, FIXME)
>
> Therefore, this paragraph needs to go away.
>
> I think there should be a flag that can be added to snd_pcm_open, like
> SND_PCM_NO_AUTO_RESAMPLE.

It's not required. It's better to allow checking if no period update 
feature is available after snd_pcm_open().

 						Jaroslav

-----
Jaroslav Kysela <perex@perex.cz>
Linux Kernel Sound Maintainer
ALSA Project, Red Hat, Inc.