Re: [PATCH v4 13/14] gunyah: rsc_mgr: Add auxiliary devices for console

Greg Kroah-Hartman
2022-10-06T06:28:04Z

On Wed, Oct 05, 2022 at 02:47:46PM -0700, Elliot Berman wrote:
>
>
> On 10/4/2022 11:21 PM, Greg Kroah-Hartman wrote:
> > On Tue, Oct 04, 2022 at 04:49:27PM -0700, Elliot Berman wrote:
> > > On 9/30/2022 5:19 AM, Greg Kroah-Hartman wrote:
> > > > On Wed, Sep 28, 2022 at 12:56:32PM -0700, Elliot Berman wrote:
> > > > > Gunyah resource manager exposes a concrete functionalities which
> > > > > complicate a single resource manager driver.
> > > >
> > > > I am sorry, but I do not understand this sentance. What is so
> > > > complicated about individual devices being created? Where are they
> > > > created? What bus?
> > >
> > > There's no complexity here with using individual devices, that's why I
> > > wanted to create secondary (auxiliary devices).
> > >
> > > IOW -- "I have a platform device that does a lot of different things. Split
> > > up the different functionalities of that device into sub devices using the
> > > auxiliary bus."
> >
> > Why not just have multiple platform devices? You control them, don't
> > make it more complex than it should be.
> >
> > And why are these platform devices at all?
> >
> > As you say:
> >
> > > A key requirement for utilizing the auxiliary bus is that there is no
> > > dependency on a physical bus, device, register accesses or regmap support.
> > > These individual devices split from the core cannot live on the platform bus
> > > as they are not physical devices that are controlled by DT/ACPI.
> >
> > These are not in the DT. So just make your own bus for them instead of
> > using a platform device. Don't abuse a platform device please.
> >
>
> I'll avoid creating platform devices. Are there any concerns with creating
> auxiliary device under the platform device?

Yes, don't do it if you do not have to, auxiliary devices are there only
if you have no other choice.

Just make 2 real devices on your own virtual bus please.

thanks,

greg k-h