[PATCH v1] phy: avoid adjust_link call if link remains down

[Sascha Hauer]

On Wed, May 29, 2024 at 07:03:40AM +0200, Oleksij Rempel wrote:
> Add a check in phy_update_status to skip calling adjust_link when the
> link status remains down. This prevents unnecessary adjust_link calls
> for PHYs that may change speed and duplex status bits before confirming
> link establishment. This issue was observed during debugging a switch
> driver, where a PHY took about 6 seconds to establish a link, causing
> multiple adjust_link calls.
> 
> Signed-off-by: Oleksij Rempel <o.rempel at pengutronix.de>
> ---
>  drivers/net/phy/phy.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
> index abd78b2c80..39a48e1519 100644
> --- a/drivers/net/phy/phy.c
> +++ b/drivers/net/phy/phy.c
> @@ -62,6 +62,9 @@ int phy_update_status(struct phy_device *phydev)
>  	    phydev->link == oldlink)
>  		return 0;
>  
> +	if (!phydev->link && phydev->link == oldlink)
> +		return 0;

I've changed the check to (!phydev->link && !oldlink) which is a bit
easier to read.

Sascha

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