Re: [PATCH v1] net: phy: dp83867: Disable EEE support as not implemented

[Andrew Lunn <andrew@lunn.ch>]

On Thu, Oct 23, 2025 at 04:48:53PM +0200, Emanuele Ghidoli wrote:
> From: Emanuele Ghidoli <emanuele.ghidoli@toradex.com>
> 
> While the DP83867 PHYs report EEE capability through their feature
> registers, the actual hardware does not support EEE (see Links).
> When the connected MAC enables EEE, it causes link instability and
> communication failures.
> 
> The issue is reproducible with a iMX8MP and relevant stmmac ethernet port.
> Since the introduction of phylink-managed EEE support in the stmmac driver,
> EEE is now enabled by default, leading to issues on systems using the
> DP83867 PHY.
> 
> Call phy_disable_eee during phy initialization to prevent EEE from being
> enabled on DP83867 PHYs.
> 
> Link: https://e2e.ti.com/support/interface-group/interface/f/interface-forum/1445244/dp83867ir-dp83867-disable-eee-lpi
> Link: https://e2e.ti.com/support/interface-group/interface/f/interface-forum/658638/dp83867ir-eee-energy-efficient-ethernet

Interesting statement this last one. "None of our gigabit PHYs
support EEE operation today."

I wounder if any of the other TI PHY drivers need this fix?

> Fixes: 2a10154abcb7 ("net: phy: dp83867: Add TI dp83867 phy")
> Cc: stable@vger.kernel.org
> Signed-off-by: Emanuele Ghidoli <emanuele.ghidoli@toradex.com>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

    Andrew