Re: net: phylink: supported modes set to 0 with genphy sfp module

[Russell King - ARM Linux admin <linux@armlinux.org.uk>]

On Mon, May 11, 2020 at 05:45:02PM +0200, Julien Beraud wrote:
> Following commit:
> 
> commit 52c956003a9d5bcae1f445f9dfd42b624adb6e87
> Author: Russell King <rmk+kernel@armlinux.org.uk>
> Date:   Wed Dec 11 10:56:45 2019 +0000
> 
>     net: phylink: delay MAC configuration for copper SFP modules
> 
> 
> In function phylink_sfp_connect_phy, phylink_sfp_config is called before
> phylink_attach_phy.
> 
> In the case of a genphy, the "supported" field of the phy_device is filled
> by:
> phylink_attach_phy->phy_attach_direct->phy_probe->genphy_read_abilities.
> 
> It means that:
> 
> ret = phylink_sfp_config(pl, mode, phy->supported, phy->advertising);
> will have phy->supported with no bits set, and then the first call to
> phylink_validate in phylink_sfp_config will return an error:
> 
> return phylink_is_empty_linkmode(supported) ? -EINVAL : 0;
> 
> this results in putting the sfp driver in "failed" state.

Which PHY is this?

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