linux-kernel - Re: [PATCH net-next] net: phy: intel-xway: workaround stale LEDs before link-up

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Message-ID: <dd6ddb96-7aa9-4142-b991-5f27a4276a92@lunn.ch>
Date: Fri, 16 Jan 2026 02:23:18 +0100
From: Andrew Lunn <andrew@...n.ch>
To: Daniel Golle <daniel@...rotopia.org>
Cc: Heiner Kallweit <hkallweit1@...il.com>,
	Russell King <linux@...linux.org.uk>,
	"David S. Miller" <davem@...emloft.net>,
	Eric Dumazet <edumazet@...gle.com>,
	Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>,
	netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
	"Benny (Ying-Tsan) Weng" <yweng@...linear.com>,
	Avinash Jayaraman <ajayaraman@...linear.com>,
	Bing tao Xu <bxu@...linear.com>,
	Juraj Povazanec <jpovazanec@...linear.com>,
	"Fanni (Fang-Yi) Chan" <fchan@...linear.com>,
	"Livia M. Rosu" <lrosu@...linear.com>,
	John Crispin <john@...ozen.org>
Subject: Re: [PATCH net-next] net: phy: intel-xway: workaround stale LEDs
 before link-up

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.

	  Andrew