Messages in this thread | | | Date | Thu, 31 May 2012 11:45:38 +0100 | From | Mark Brown <> | Subject | Re: [alsa-devel] [PATCH v5] sound/soc/lapis: add platform driver for ML7213 |
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On Thu, May 31, 2012 at 02:38:30PM +0900, Tomoya MORINAGA wrote: > On Wed, May 30, 2012 at 9:14 PM, Mark Brown
> > Please re-read what I wrote.
> Let me clarify. > Do you say native DMA driver API like dmaengine_prep_slave_sg(), > dmaengine_submit() shouldn't be used from ASoC driver, right ?
Your driver should be written in terms of the ASoC DMA framework.
> > No, all current mainline drivers using the library use cyclic DMA.
> I can't see any driver uses cyclic DMA. (I saw linux-next's tree from > kernel.org.) > Where is your saying "current mainline" ?
Linus' tree, or mine. Have you even looked at the soc-dmaengine-pcm code? It uncondtionally requests a cyclic channel.
> However I think it seems difficult for supporting all devices. > Because hardware dependency control code can't be added. > For example, for ML7213, needs interrupt control both before/after DMA transfer. > However, in case of using soc-dmaengine, the control can't be done. > Because the processing is in soc-dmaengine.
Please be more specific. What are the concrete problems that you see? Why is it not possible to address them within the framework? [unhandled content-type:application/pgp-signature] | |