[alsa-devel] [PATCH 1/2] ASoC: rt5677: Add ACPI device probing

[Rafael J. Wysocki]

On Wednesday, November 26, 2014 11:17:16 AM Mark Brown wrote:
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> On Tue, Nov 25, 2014 at 05:48:24PM -0800, Darren Hart wrote:
> > On 11/25/14 10:43, Mark Brown wrote:
> 
> > > Link from where - do we want to talk to the ACPI/UEFI forum and
> > > figure out some kind of fast track process for them to add an "it's
> > > already covered by DT, see here" entry to their database for
> > > example?  We also ought to work out how to make sure ACPI IDs are
> > > registered there as well, should be possible to have something
> > > simple as part of that.
> 
> > As to registering ACPI IDs, I believe this is the right link:
> > http://www.uefi.org/PNP_ACPI_Registry
> 
> No, those are vendors as far as I can tell.  I mean identifiers for
> specific devices - it appears to be common for for example Intel to
> allocate identifiers for devices they don't produce, I'd expect there to
> be some effort to keep track of that especially given that _DSD
> properties may well end up being specific to the identifier used to
> register in cases of parallel evolution.

The vendor (or more precisely the owner of the initial 3 or 4 letter code)
is supposed to do that.  I'm not aware of any common registry of those IDs
for all vendors.

> > Or did you mean a HID/CID<->DSD mapping?
> 
> I don't really know what that is, sorry.

The device ID is supposed to determine the way all of the ACPI objects for that
device will work, including what is returned by _DSD.  Pretty much in analogy
with PCI device IDs.

-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.