Re: [PATCH 0/2] net: stmmac: allow sharing MDIO lines

Russell King (Oracle)
2023-08-08T19:26:13Z

On Tue, Aug 08, 2023 at 08:26:22PM +0200, Bartosz Golaszewski wrote:
> When I say "device unbind", I don't just mean manual unbinding using
> sysfs. I mean any code path (rmmod, unplugging the USB, etc.) that
> leads to the device being detached from its driver. This is a
> perfectly normal situation and should work correctly.
>
> I won't be fixing it for this series but may end up looking into
> establishing some kind of device links between MACs and their "remote"
> PHYs that would allow to safely unbind them.

I don't think you're the first to suggest that!

That gets difficult - because although the PHY may be a different
driver, the MDIO bus may be provided by the _same_ hardware as the
ethernet MAC itself. So you end up with a circular dependency - the
PHY device depends on the MDIO bus device (which is the ethernet MAC)
and then you make the ethernet MAC depend on the PHY device.

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