Re: [PATCH 10/21] net: phy: add X-Powers AC200 EPHY control driver

However, the MFD and networking portions necessarily meet at the AC200
EPHY function. I do not think the correct way to avoid that
cross-subsystem dependency is to make a driver bound to an MDIO
phy_device take ownership of registers and resources belonging to an
MFD device.

We can pull the MFD Maintainer into this, but an MFD core driver
typically just provides methods to access the shared registers, and
instantiates drivers to make use of those shared registers. In this
case, we don't need the instantiate part, that happens via the MDIO
bus model. But we do need access to the shared registers. I personally
don't care too much how that is done, but regmap would be normal.

The PHY driver should then drive the whole, entire PHY, using both
MDIO and whatever method the MFD exports to give access to the
registers.

	Andrew