[alsa-devel] possible problem in s3c24xx-pcm.c in git-devel branch

[christian pellegrin]

On Thu, Nov 13, 2008 at 4:17 PM, Mark Brown <broonie at sirena.org.uk> wrote:
> On Thu, Nov 13, 2008 at 03:57:08PM +0100, christian pellegrin wrote:
>
>>
>> but this really could be "playing with DMA" since I'm not sure why
>> there is a 1 (since min_period is 2 I would guess 2 is the right
>> value). Anyway with this change play and capture work well.
>
> See the commit log - the underlying DMA code restricts the number of
> buffers that can be queued up prior to the start of DMA.
>
>>

AFAIK it's limited to 2 transfers, one loaded and one running. It
could beneficial to have more of them (so the DMA doesn't stop if one
interrupt is delayed for too much time). But I don't know if it's so
critical. A period (4k) with cd quality sound takes 23 ms to be
played. An embedded system not responding to irqs for all this time
probably has worse issues.

-- 
Christian Pellegrin, see http://www.evolware.org/chri/
"Real Programmers don't play tennis, or any other sport which requires
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