From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: periods_max initialization in snd_usb_hardware
Date: Wed, 27 Jun 2012 21:29:53 +0200
Message-ID: <4FEB5F31.8040809@ladisch.de>
References: <CA+F9FsDoX=X14qpzgoH+Fm8oEq8f36fwa02J1fQTD9eqbCnVSw@mail.gmail.com>
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To: Amit Nagal <helloin.amit@gmail.com>
Cc: alsa-devel@alsa-project.org
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Amit Nagal wrote:
> snd_usb_hardware is defined in sound/usb/pcm.c as ...
> periods_max is intialized with value = 1024 .
>
> but going by buffer_bytes_max and period_bytes_min value defined above ,
> periods_max = ( buffer_bytes_max / period_bytes_min ) = 16384 .
>
> why this upper cap of  1024 is maintained for  periods_max even though from
> calculation it comes as 16384 ?

The buffer is entirely handled by software; these limits are pretty much
arbitrary.

If there is a reason to change these limits, just send a patch.  :)


Regards,
Clemens