[alsa-devel] davinci_request_dma()
I'm looking for a little bit more help reading the SOC code. In particular, I'm reading davinci-pcm.c, and function davinci_pcm_dma_request, which makes two calls to davinci_request_dma. However, when I grep for davinci_request_dma, the only places I can find it are in davinci_pcm_dma_request itself!
[jkacur@mydcore linux-2.6.26]$ grep -rn davinci_request_dma * sound/soc/davinci/davinci-pcm.c:143: ret = davinci_request_dma(prtd->params->channel, prtd->params->name, sound/soc/davinci/davinci-pcm.c:150: ret = davinci_request_dma(PARAM_ANY, "Link",
Either I'm missing something, or this code wouldn't even compile. I would appreciate any help in understanding this.
Thank you.
On Thu, Oct 16, 2008 at 10:58:58AM +0200, John Kacur wrote:
[The ASoC DaVinci driver uses davinci_request_dma() but...]
However, when I grep for davinci_request_dma, the only places I can find it are in davinci_pcm_dma_request itself!
...
Either I'm missing something, or this code wouldn't even compile. I would appreciate any help in understanding this.
It was discovered a while ago that the code depends on an unmerged set of DMA API updates. See this thread for more info:
http://mailman.alsa-project.org/pipermail/alsa-devel/2008-June/008674.html
To be honest, I had expected that the required updates would have been merged by now but it seems not. CCing the DaVinci list - I don't know what the status is on merging the new DMA API?
On Thu, Oct 16, 2008 at 11:08 AM, Mark Brown broonie@sirena.org.uk wrote:
On Thu, Oct 16, 2008 at 10:58:58AM +0200, John Kacur wrote:
[The ASoC DaVinci driver uses davinci_request_dma() but...]
However, when I grep for davinci_request_dma, the only places I can find it are in davinci_pcm_dma_request itself!
...
Either I'm missing something, or this code wouldn't even compile. I would appreciate any help in understanding this.
It was discovered a while ago that the code depends on an unmerged set of DMA API updates. See this thread for more info:
http://mailman.alsa-project.org/pipermail/alsa-devel/2008-June/008674.html
To be honest, I had expected that the required updates would have been merged by now but it seems not. CCing the DaVinci list - I don't know what the status is on merging the new DMA API?
Thanks for the info. Is there a suggested SOC driver to use as a reference driver in 2.6.26?
On Thu, Oct 16, 2008 at 12:01 PM, Mark Brown broonie@sirena.org.uk wrote:
On Thu, Oct 16, 2008 at 11:24:06AM +0200, John Kacur wrote:
Thanks for the info. Is there a suggested SOC driver to use as a reference driver in 2.6.26?
What are you looking to do - if you're looking for an ASoC driver for DaVinici that's the only one I'm aware of.
No, I'm looking at doing ASoC drivers in general, not for a DaVinci processor specifically.
On Thu, Oct 16, 2008 at 12:05:41PM +0200, John Kacur wrote:
On Thu, Oct 16, 2008 at 12:01 PM, Mark Brown broonie@sirena.org.uk wrote:
What are you looking to do - if you're looking for an ASoC driver for DaVinici that's the only one I'm aware of.
No, I'm looking at doing ASoC drivers in general, not for a DaVinci processor specifically.
PXA, OMAP or S3C24xx should all be good bets in terms of platform support. Out of interest, what are you working on?
On Thu, Oct 16, 2008 at 2:08 PM, Mark Brown broonie@sirena.org.uk wrote:
On Thu, Oct 16, 2008 at 12:05:41PM +0200, John Kacur wrote:
On Thu, Oct 16, 2008 at 12:01 PM, Mark Brown broonie@sirena.org.uk wrote:
What are you looking to do - if you're looking for an ASoC driver for DaVinici that's the only one I'm aware of.
No, I'm looking at doing ASoC drivers in general, not for a DaVinci processor specifically.
PXA, OMAP or S3C24xx should all be good bets in terms of platform support. Out of interest, what are you working on?
arm Jade + max5556
On Thu, Oct 16, 2008 at 2:08 PM, Mark Brown broonie@sirena.org.uk wrote:
On Thu, Oct 16, 2008 at 12:05:41PM +0200, John Kacur wrote:
On Thu, Oct 16, 2008 at 12:01 PM, Mark Brown broonie@sirena.org.uk wrote:
What are you looking to do - if you're looking for an ASoC driver for DaVinici that's the only one I'm aware of.
No, I'm looking at doing ASoC drivers in general, not for a DaVinci processor specifically.
PXA, OMAP or S3C24xx should all be good bets in terms of platform support. Out of interest, what are you working on?
PXA appears to be incomplete too! s3c24xx looks like the only one that might work. (at least with 2.6.26 mainline). If I'm not mistaken PXA must also be living in an external git tree, and is only partially implemented in the mainline kernel.
Thanks again for all the hints and info.
On Mon, Oct 20, 2008 at 11:17:41AM +0200, John Kacur wrote:
PXA appears to be incomplete too! s3c24xx looks like the only one that might work. (at least with 2.6.26 mainline). If I'm not mistaken PXA must also be living in an external git tree, and is only partially implemented in the mainline kernel.
What makes you say this? I do a very large part of my development with mainline PXA boards.
On Mon, Oct 20, 2008 at 11:49 AM, Mark Brown broonie@sirena.org.uk wrote:
On Mon, Oct 20, 2008 at 11:17:41AM +0200, John Kacur wrote:
PXA appears to be incomplete too! s3c24xx looks like the only one that might work. (at least with 2.6.26 mainline). If I'm not mistaken PXA must also be living in an external git tree, and is only partially implemented in the mainline kernel.
What makes you say this? I do a very large part of my development with mainline PXA boards.
For example, sound/soc/pxa/corgi.c calls machine_is_corgi(), I can only find uses of machine_is_corgi(), but no implementation.
On Mon, Oct 20, 2008 at 11:58:14AM +0200, John Kacur wrote:
On Mon, Oct 20, 2008 at 11:49 AM, Mark Brown broonie@sirena.org.uk wrote:
On Mon, Oct 20, 2008 at 11:17:41AM +0200, John Kacur wrote:
PXA appears to be incomplete too! s3c24xx looks like the only one that
What makes you say this? I do a very large part of my development with mainline PXA boards.
For example, sound/soc/pxa/corgi.c calls machine_is_corgi(), I can only find uses of machine_is_corgi(), but no implementation.
The machine_is_foo() stuff is autogenerated by the ARM build system.
BTW, your MUA appears to be broken - I'm getting two mails from you, one copy which is sent to both the list and to me and another copy which is sent to me only. As far as I can tell the content is identical.
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Mark Brown