[alsa-devel] [PATCH 2/2] add API to allow disabling period interrupt

Jaroslav Kysela perex at perex.cz
Tue Nov 2 09:38:10 CET 2010

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

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


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

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