From mboxrd@z Thu Jan  1 00:00:00 1970
From: Clemens Ladisch <clemens@ladisch.de>
Subject: Re: what is period_size, buffer_size and boundary size,
 i confuse them
Date: Mon, 10 Dec 2012 09:24:37 +0100
Message-ID: <50C59C45.7040109@ladisch.de>
References: <5ec59db3.354.13b83dc3158.Coremail.l9jj@163.com>
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l9jj@163.com wrote:
> does  the variable buffer_size equal to  DMA size?

Yes.

> (2)how the pos>buffer_size will happen in the interface snd_pcm_update_hw_ptr0()?

It happens when your driver has a bug.  The .pointer callback always must
return value that is inside the DMA buffer.


Regards,
Clemens