[alsa-devel] [PATCH] ASoC drivers for the Freescale MPC8610 SoC
david at gibson.dropbear.id.au
Thu Jan 10 04:49:19 CET 2008
On Mon, Jan 07, 2008 at 06:28:54PM +0000, Mark Brown wrote:
> On Mon, Jan 07, 2008 at 09:52:03AM -0600, Timur Tabi wrote:
> > David Gibson wrote:
> > > Ok, but couldn't you strucutre your I2S or fabric driver so that it
> > > only becomes fully operational once the codec driver has registered
> > > with it?
> > Not in ASoC V1. You have to understand, ASoC V1 was designed without any
> > consideration for runtime-bindings and other OF goodies. All connections
> > between the drivers are static, literally. In fact, I wouldn't be surprised if
> > some ASoC drivers cannot be compiled as modules.
> I'd just like to emphasise this point - ASoC v1 really doesn't
> understand the idea that the components of the sound subsystem might be
> probed separately. It's set up to handle bare hardware with everything
> being probed from code in the machine/fabric driver. This makes life
> very messy for platforms with something like the device tree.
> As has been said, handling this properly is one of the major motivations
> behind ASoC v2.
Nonetheless, messing up the device tree to workaround ASoC V1's silly
limitations is not a good idea. The device tree must represent the
hardware as much as possible. If that means we have to have a bunch
of platform-specific hacks to instatiate the drivers in the correct
order / combination, that's unfortunate, but there you go.
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
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