Re: [PATCH net] net: explicitly check in of_phy_is_fixed_link() for managed = "in-band-status"

From: Russell King (Oracle)
Date: Tue Aug 12 2025 - 07:23:27 EST


On Tue, Aug 12, 2025 at 01:59:28PM +0300, Vladimir Oltean wrote:
> And the other sub-case is when the MDIO-less PHY is also silent on the
> in-band autoneg front. In that case, the firmware description would look
> like this (b):
>
> mac {
> phy-mode = "sgmii";
>
> fixed-link {
> speed = <10000>;
> full-duplex;
> };
> };
>
> (side note: phylink would probably have something to object against the
> PHY not reporting its state in any way, and would consider the setup
> invalid, even if in some cases it would work. This is because its
> configuration may not be fixed, and there would be no way to be notified
> of updates)

Both of these are fully supported by phylink, and your side note is
incorrect. Phylink provides all the functionality.

With the description in (b), if a MAC driver wishes to, it can provide
phylink_config->get_fixed_state() and override the speed, duplex and
pause in the same way that is possible with fixed PHY.

So, unless I missed something, I don't think your commit description
is correct. If it is correct, it is ambiguous.

Thanks.

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