[PATCH v2 1/6] Add ancillary bus support

[Ertman, David M]

> -----Original Message-----
> From: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
> Sent: Tuesday, October 6, 2020 8:18 AM
> To: Leon Romanovsky <leon at kernel.org>; Ertman, David M
> <david.m.ertman at intel.com>
> Cc: alsa-devel at alsa-project.org; parav at mellanox.com; tiwai at suse.de;
> netdev at vger.kernel.org; ranjani.sridharan at linux.intel.com;
> fred.oh at linux.intel.com; linux-rdma at vger.kernel.org;
> dledford at redhat.com; broonie at kernel.org; jgg at nvidia.com;
> gregkh at linuxfoundation.org; kuba at kernel.org; Williams, Dan J
> <dan.j.williams at intel.com>; Saleem, Shiraz <shiraz.saleem at intel.com>;
> davem at davemloft.net; Patil, Kiran <kiran.patil at intel.com>
> Subject: Re: [PATCH v2 1/6] Add ancillary bus support
> 
> Thanks for the review Leon.
> 
> >> Add support for the Ancillary Bus, ancillary_device and ancillary_driver.
> >> It enables drivers to create an ancillary_device and bind an
> >> ancillary_driver to it.
> >
> > I was under impression that this name is going to be changed.
> 
> It's part of the opens stated in the cover letter.
> 
> [...]
> 
> >> +	const struct my_driver my_drv = {
> >> +		.ancillary_drv = {
> >> +			.driver = {
> >> +				.name = "myancillarydrv",
> >
> > Why do we need to give control over driver name to the driver authors?
> > It can be problematic if author puts name that already exists.
> 
> Good point. When I used the ancillary_devices for my own SoundWire test,
> the driver name didn't seem specifically meaningful but needed to be set
> to something, what mattered was the id_table. Just thinking aloud, maybe
> we can add prefixing with KMOD_BUILD, as we've done already to avoid
> collisions between device names?
> 
> [...]

Since we have eliminated all IDA type things out of the bus infrastructure,
I like the idea of prefixing the driver name with KBUILD_MODNAME through
a macro front.  Since a parent driver can register more than one ancillary driver,
this allow the parent to have an internally meaningful name while still ensuring
its uniqueness.

-DaveE