[alsa-devel] [PATCH 07/22] ASoC: Ux500: Initialise PCM from MSP probe rather than as a device

Lee Jones lee.jones at linaro.org
Thu Aug 23 16:59:06 CEST 2012

On Thu, Aug 23, 2012 at 03:37:57PM +0100, Mark Brown wrote:
> On Thu, Aug 23, 2012 at 02:26:19PM +0100, Lee Jones wrote:
> > > I think Ola is suggesting probing the DMA driver from the machine which
> > > will also work though I'm not 100% sure if I'm parsing the above
> > > correctly.  The issue in DT terms is that if the DMA controller is
> > > shared with a bunch of other IPs then it should have one node shared
> > > between them all and not a bunch of shim nodes inserted in the middle
> > > which only exists due to the way Linux instantiates stuff.
> > When you say 'machine', do you mean from arch/<arch>/mach-*? If so, I'm
> > keen for that not to happen.
> No, sound/soc/ux500/snowball.c or whatever.  At least that's my guess.

Ah, I see. Maybe the mop500.c file then.

> > > They instantiate the PCM driver dynamically from the DAI when it's
> > > probed which is pretty much what you're patch is doing.
> > So they do it in the same why I have with this patch? Do you know why
> > Ola might think this is a bad idea?
> I'm not 100% sure, I'm guessing it might be down to the fact that you
> end up with multiple PCM drivers.  We could avoid that with refcounting
> but nobody's really worried about it.

I think I'll wait for Ola to get back, as he's the expert on this stuff.

I'll attempt to re-jig the patch-set, as this is a blocker atm.

Lee Jones
Linaro ST-Ericsson Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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