Re: [PATCH net-next] net: phy: intel-xway: workaround stale LEDs before link-up
From: Daniel Golle
Date: Thu Jan 15 2026 - 21:06:54 EST
On Fri, Jan 16, 2026 at 02:23:18AM +0100, Andrew Lunn wrote:
> On Thu, Jan 15, 2026 at 11:40:38PM +0000, Daniel Golle wrote:
> > Due to a bug in some PHY internal firmware, manual control as well as
> > polarity configuration of the PHY LEDs has no effect until a link has
> > been detected at least once after reset. Apparently the LED control
> > thread is not started until then.
> >
> > As a workaround, clear the BMCR_ANENABLE bit for 100ms to force the
> > firmware to start the LED thread, allowing manual LED control and
> > respecting LED polarity before the first link comes up.
> >
> > In case the legacy default LED configuration is used the bug isn't
> > visible, so only apply the workaround in case LED configuration is
> > present in the device tree.
>
> You should consider the case of forced links, where autoneg is
> disabled. Under such conditions, you should not leave autoneg enabled.
If BMCR_ANENABLE has already been disabled after a reset we can skip
this workaround entirely, as doing that once for more than 100ms is all
needed for the LEDs to work properly.
However, I'm not aware of .config_init ever being run again after the
intial attachment of the PHY and call to phy_init_hw().
All user-defined configuration happens after that, and would then remove
the BMCR_ANENABLE bit just like it would do it if it was set by the
hardware after reset.
(note that BMCR_ANENABLE is set as part of the reset value of BMCR on
this PHY)
But maybe I'm getting something wrong here?