Re: [PATCH net-next v5 1/5] dt-bindings: mfd: x-powers: Add AC200

[James Hilliard]

On Tue, Aug 11, 2026 at 1:07 AM Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote:
>
> On 09/08/2026 22:28, James Hilliard wrote:
> > The AC200 is an I2C-controlled mixed-signal companion IC containing
> > audio, video, RTC and Fast Ethernet PHY functions.
> >
> > Describe the parent device and its shared input clock. The Ethernet PHY
> > is represented by a PHY package on its MDIO bus, with a phandle back to
> > this device for access to the package control registers, so it does not
> > require an MFD child node. Function-specific supplies belong to their
> > consumer bindings rather than the shared parent.
> >
> > The input clock must run at 24 or 27 MHz when the Ethernet PHY is used,
> > matching the rates encoded by its documented clock selector.
> >
> > Signed-off-by: James Hilliard <james.hilliard1@xxxxxxxxx>
> > ---
>
> I do not understand why MFD and net are combined. And nothing in top
> part of cover letter explains me that (which I asked already - any
> dependency or merging is THE MOST important information. Where do you
> put the most important information which maintainers should see
> immediately?)

The AC200 PHY control registers reside in the I2C-managed
multifunction device. The AC200 PHY backend therefore consumes
the regmap published by the AC200 MFD driver, while the AC300
backend accesses its control registers directly over MDIO.

The managed syscon registration change is used by the AC200 MFD
provider. The net driver itself uses the existing syscon lookup
interface, so there is no compile-time dependency from the net
patches on the new syscon API. There is, however, an unavoidable
runtime dependency for AC200 on its I2C provider. AC300 has no
such dependency.

> Bundling it together suggests this is somehow incomplete and later will
> be finished, which is wrong by itself. How to fix it - decouple
> dependencies.

Could you clarify whether you mean that the MFD and net changes
should be sent as separate submissions, or that the driver
interface should be redesigned so the net side has no dependency
on the AC200 MFD provider?

>
> Best regards,
> Krzysztof