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User-Agent: Mutt/1.10.1 (2018-07-13) Cc: ALSA development , Tzung-Bi Shih , Greg Kroah-Hartman , Linux Kernel Mailing List , Hung-Te Lin , Tzung-Bi Shih , Sean Paul , Srinivas Kandagatla , Dylan Reid , Guenter Roeck , Cheng-yi Chiang Subject: Re: [alsa-devel] [PATCH] firmware: vpd: Add an interface to read VPD value X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1617050330080636101==" Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" --===============1617050330080636101== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="xgyAXRrhYN0wYx8y" Content-Disposition: inline --xgyAXRrhYN0wYx8y Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Oct 08, 2019 at 08:14:43AM -0700, Stephen Boyd wrote: > Quoting Cheng-yi Chiang (2019-10-07 11:50:31) > > IMO the nvmem approach would create more complexity to support this > > simple usage. Plus, the underlying assumption of accessing data with > > offset in a buffer does not fit well with the already parsed VPD > > values in a list of vpd_attrib_info. But if you strongly feel that > > this is a better approach I can work toward this. > I'm not sure how an ACPI system like this would work because my exposure > to ACPI is extremely limited. I would expect there to be some sort of > firmware property indicating that an nvmem should be used and it's > provided by VPD or for firmware to parse VPD itself and put the > information into the ACPI table for this device. I fear this is optimistic. It's fairly idiomatic for ACPI for stuff like this to be keyed off DMI information rather than integrated with anything, basically once you get out of the bits that are explictly standardized you're into board file territory. There is the _DSD stuff for using DT properties in ACPI but it's had limited use AFAICT. --xgyAXRrhYN0wYx8y Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl2d4oQACgkQJNaLcl1U h9AkxAf/WtJz8gLoIEhfmWFM3Y4Qvz6cFPqsO5kNBWEQH18SykjRbNumBoeynRlg 0j+2Vz6nFCns429nsLJ/ooS/sKbFGY9UfK8TDxJdUiifheot3MJahzT92vTj7LbB AGk+U9e4/n627enaqdqDGmf8m2aPpUqJdmPhr0zuV8/N2c3SMzCTcBXB4BGqkd9I My1IdAX5qlmi5+Q0SXmUJjwJtiVs0rdurw3TcKaOdpvhDmyLdJVuaLYmM1QXh0v8 G5UNLVXzEN0RJZO7dDnbImprk1hOTC7Sze0T5ykh0W0UeydBAw7stk0zVGYro7jO K/UYMfOOX3LPFttYf22WeGOLFUf5TQ== =UWfy -----END PGP SIGNATURE----- --xgyAXRrhYN0wYx8y-- --===============1617050330080636101== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Alsa-devel mailing list Alsa-devel@alsa-project.org https://mailman.alsa-project.org/mailman/listinfo/alsa-devel --===============1617050330080636101==--