Re: [PATCH v2 2/2] mfd: Add initial synology microp driver

From: Lee Jones

Date: Mon Mar 09 2026 - 12:06:50 EST


On Mon, 09 Mar 2026, Danilo Krummrich wrote:

> On Mon Mar 9, 2026 at 4:15 PM CET, Lee Jones wrote:
> > On Mon, 09 Mar 2026, Markus Probst wrote:
> >
> >> On Mon, 2026-03-09 at 14:32 +0100, Danilo Krummrich wrote:
> >> > On Mon Mar 9, 2026 at 1:52 PM CET, Markus Probst wrote:
> >> > > Yes. I will split it into multiple drivers using the aux bus in the
> >> > > next revision.
> >> >
> >> > Independent of the other discussion whether this belongs into the kernel in the
> >> > first place, reading over the cover letter and commit message I understood the
> >> > following.
> >> >
> >> > "Synology uses a microcontroller in their NAS devices connected to a serial
> >> > port [...]" controlling LEDs, fan speeds, a beeper, etc.
> >> >
> >> > I.e. it muliplexes several physical functions that belong to different
> >> > subsystems, such as hwmon, input, etc. over a single serial port.
> >> >
> >> > This sounds like a textbook candidate for MFD to me.
> >
> > Then you do not know what a textbook candidate for MFD is. :)
> >
> > What part of the MFD API does this device utilise?
>
> I did *not* say this driver - as in the code that was posted - is a textbook
> example for MFD.
>
> I said that the hardware that is supposed to be fully supported eventually is a
> textbook candidate for an MFD driver, i.e. it should use things like
> devm_mfd_add_devices().
>
> I think this was obvious from what I wrote above.

No, not at all. Or there would be no confusion. :)

But yes, I agree, if re-authored this could fit into MFD.

--
Lee Jones [李琼斯]