From 5e5b39aa6f82e74a2b4caa79005b2e673f657809 Mon Sep 17 00:00:00 2001 From: "Russell King (Oracle)" Date: Fri, 15 Aug 2025 12:32:21 +0100 Subject: [PATCH] net: stmmac: explain the phylink_speed_down() call in stmmac_release() The call to phylink_speed_down() looks odd on the face of it. Add a comment to explain why this call is there. phylink_speed_up() is always called in __stmmac_open(), and already has a comment. Signed-off-by: Russell King (Oracle) Reviewed-by: Andrew Lunn Link: https://patch.msgid.link/E1umsfV-008vKv-1O@rmk-PC.armlinux.org.uk Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index b9e8df90e7b5d..0bbdc1f1a6919 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -4138,8 +4138,13 @@ static int stmmac_release(struct net_device *dev) struct stmmac_priv *priv = netdev_priv(dev); u32 chan; + /* If the PHY or MAC has WoL enabled, then the PHY will not be + * suspended when phylink_stop() is called below. Set the PHY + * to its slowest speed to save power. + */ if (device_may_wakeup(priv->device)) phylink_speed_down(priv->phylink, false); + /* Stop and disconnect the PHY */ phylink_stop(priv->phylink); phylink_disconnect_phy(priv->phylink); -- 2.51.0