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User-Agent: Mutt/1.10.1 (2018-07-13) Cc: alsa-devel@alsa-project.org, Kiran Patil , tiwai@suse.de, gregkh@linuxfoundation.org, ranjani.sridharan@intel.com, pierre-louis.bossart@linux.intel.com, Ranjani Sridharan , Fred Oh , parav@nvidia.com, jgg@nvidia.com, Dan Williams , Shiraz Saleem , Parav Pandit 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: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" --hK8Uo4Yp55NZU70L Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Sep 30, 2020 at 03:50:46PM -0700, Dave Ertman wrote: > Documentation/driver-api/ancillary_bus.rst | 230 +++++++++++++++++++++ > Documentation/driver-api/index.rst | 1 + It would probably be useful to have the documentation in a separate patch, it's a huge proportion of the patch and would make it much more approachable. > +are controlled by DT/ACPI. The same argument applies for not using MFD in this > +scenario as MFD relies on individual function devices being physical devices > +that are DT enumerated. See my commments on the cover letter about MFD, this is just not true. > +An example for this kind of requirement is the audio subsystem where a single > +IP is handling multiple entities such as HDMI, Soundwire, local devices such as > +mics/speakers etc. The split for the core's functionality can be arbitrary or This is not a requirement of the audio subsystem, this is to do with how the Intel audio hardware has been implemented on their modern SoCs. > +int ancillary_device_initialize(struct ancillary_device *ancildev) > +{ > +int __ancillary_device_add(struct ancillary_device *ancildev, const char *modname) > +{ It can be useful to have this split but there's also going to be plenty of cases where people just need to register a device based on the struct ancilliary_device straight away so it would be good to at least have a standard ancilliary_device_new() (or whatever) that does both steps in one. As Greg said in his review this split model is a bit more fiddly to use and frequently leads to error handling problems in drivers. --hK8Uo4Yp55NZU70L Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl912SwACgkQJNaLcl1U h9DvcQf/Sphve8mdhn3UFbvbhCK4cib3j+Ittrlo2xPuot13fLVmquU4v6iFoL1F Nfq5FiEHMrrhX1Z0ttbBpEMiGSn/mksuQUhc3qJtT+1fnBr7YxPfS+PY6+/Jb0JS FpCRY/Tt1o0x+5Od8C8P9KsXlfzXSx3nxRTS28xPYM14Pm4Ix8911TJtFgWCIipY h+NuED+nLyeNaDsnw4XnxOEk7STg49Z1QFSu3DXesFoJghpUlbD/dT0dLO0oPLc5 TAjv0LOpghENQ97C4l84RVGeFTqemEpeBAmrp/++zF0gAQ/V4Z0m1I9wUa7KjUnH 2j0uI0jc+oQ0Bpc5WvilXkFouqMuMg== =XrlR -----END PGP SIGNATURE----- --hK8Uo4Yp55NZU70L--