embedded OSS sound driver

From: Jacky Cheung (jackylb_at_yahoo.com)
Date: 07/21/04 

Date: Wed, 21 Jul 2004 18:57:20 +0800

Hi all,

Currently I am working an embedded OSS sound driver, my sound IC is
controlled by i2c and with ssi channels.

Due to my i2c is really heavy loaded, so I need to disable the dma
before access the the sound IC register (e.g. volume control)via i2c.

I use the following two scripts to disable the dma.

dmaflags = claim_dma_lock();
disable_dma(ssi_dma);

And I use these lines to enable the dma.

enable_dma(ssi_dma);
release_dma_lock(dmaflags);

However, I find that when I tune the volume very frequently, the sound
play faster than normal. I am very sure that it caused by stopping dma,
but I don't know how to fix it. Any idea?

Many thanks.

Regards,
Jacky

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