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: Sun, 09 Dec 2012 17:22:27 +0100
Message-ID: <50C4BAC3.4030300@ladisch.de>
References: <65bdafa4.4e24.13b8019be47.Coremail.l9jj@163.com>
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l9jj wrote:
> can anyone help me to figure out  the concepts between period_size ,buffer_size and boundary size?
> n * period_size = buffer_size?

Yes.  On many devices, n is not required to be an integer.

> m * buffer_size = boundary_size?

Yes, where m is very big.  In applications, the actual value of the boundary
size does not matter (except as a special value for some sw params).

> and how the dma buffer mapped to the alsa buffer?

The DMA buffer _is_ the ALSA buffer.


Regards,
Clemens