Re: [PATCH net-next v4 1/4] dt-bindings: mfd: x-powers: Add AC200

From: Andrew Lunn

Date: Sun Aug 09 2026 - 16:48:39 EST


On Sun, Aug 09, 2026 at 01:33:22PM -0600, James Hilliard wrote:
> On Sun, Aug 9, 2026 at 9:34 AM Andrew Lunn <andrew@xxxxxxx> wrote:
> >
> > > +description:
> > > + The AC200 is a mixed-signal companion IC containing audio, video, RTC and
> > > + Fast Ethernet PHY functions. Its control registers are accessed over I2C.
> > > +
> > > +properties:
> > > + compatible:
> > > + const: x-powers,ac200
> > > +
> > > + reg:
> > > + maxItems: 1
> > > +
> > > + clocks:
> > > + maxItems: 1
> > > + description:
> > > + AC200 input clock. When using the Ethernet PHY, its configured rate must
> > > + be 24 or 27 MHz, matching the rates encoded by the documented EPHY clock
> > > + selector.
> >
> > What is the scope of this clock. Is the PHY the only consumer?
>
> No. This is the AC200's external CKI system-clock input, not an
> EPHY-local clock.

O.K, good.

> > > + ephy-vcc-supply:
> > > + description: 3.3 V supply for the Ethernet PHY analog front end
> >
> > This sounds to be specific to the PHY, so the PHY driver should be the
> > consumer, not the MFD as a whole. That then would allow the PHY to
> > perform power management, turn the regulator off when the link is
> > admin down, so suspended.
>
> EPHY_VCC is specific to the Ethernet PHY, even when a board connects it
> to the same physical 3.3 V regulator as other AC200 supply pins. The
> regulator core will retain the shared rail while any other consumer
> still has it enabled.
>
> For v5 I have removed ephy-vcc-supply from the AC200 MFD node and moved
> the supply to the Ethernet PHY package. Both variants now use a common
> vcc-supply property, connected to EPHY_VCC on AC200 and VCC1 on AC300.

Great, thanks

Andrew