Re: [alsa-devel] Proposal for more reliable audio DMA.

On Mon, Jun 22, 2009 at 12:27 PM, James Courtier-Duttonjames.dutton@gmail.com wrote:

2009/6/21 Jon Smirl jonsmirl@gmail.com:

...

New last buffer is set to automatically stop DMA.

How do you do this? DMA transfers on sound cards are a ring buffer. There is no automatic stop feature.

I don't about all hardware, but all of the hardware I've worked with works both ways, ring or stop at the end.

DMA transfers for network packets wouldn't work in the ring buffer model, you need the stop at the end capability.

You set the dma pointers, start dma going in a loop and that is it. You can then stop the DMA on command but not as a result of a buffer end.