[RFC PATCH net-next 9/9] net: phylink: report no link modes while a late PHY is missing
From: Aleksei Sviridkin <hidden>
Date: 2026-08-29 05:26:11
Also in:
linux-devicetree, lkml
Subsystem:
ethernet phy library, networking drivers, sff/sfp/sfp+ module support, the rest · Maintainers:
Andrew Lunn, Heiner Kallweit, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Russell King, Linus Torvalds
A port waiting for its PHY reported the MAC's full set of link modes and accepted settings for them, which describes a link that cannot come up. Report an empty set and refuse to configure, matching what an empty SFP cage already does. The EEE calls need no such guard: they already return -EOPNOTSUPP when no PHY is attached. Assisted-by: LLM Signed-off-by: Aleksei Sviridkin <redacted> --- drivers/net/phy/phylink.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+)
diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index eda7b61ba5d1..6fbd1fa0be78 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c@@ -2284,6 +2284,12 @@ EXPORT_SYMBOL_GPL(phylink_connect_phy); /* Ceiling that interval backs off to once a connect attempt has failed. */ #define PHYLINK_SLOW_PHY_POLL_MAX_MS 30000 +/* True while a PHY declared slow-to-probe has not been connected yet. */ +static bool phylink_slow_phy_pending(struct phylink *pl) +{ + return pl->slow_phy_fwnode && !pl->phydev; +} + /* A phy-handle has resolved only once it names a device with its own driver * bound. A device that is absent, or present with the generic driver bound to * it, is equally unusable: this is the state slow-to-probe waits out, and both
@@ -3106,6 +3112,17 @@ int phylink_ethtool_ksettings_get(struct phylink *pl, else kset->base.port = pl->link_port; + /* Until the PHY arrives the port can do nothing, so report no link + * modes at all rather than the MAC's own capabilities, which is what + * an empty SFP cage reports. + */ + if (phylink_slow_phy_pending(pl)) { + linkmode_zero(kset->link_modes.supported); + kset->base.speed = SPEED_UNKNOWN; + kset->base.duplex = DUPLEX_UNKNOWN; + return 0; + } + linkmode_copy(kset->link_modes.supported, pl->supported); switch (pl->act_link_an_mode) {
@@ -3173,6 +3190,12 @@ int phylink_ethtool_ksettings_set(struct phylink *pl, ASSERT_RTNL(); + /* Without a PHY and without an SFP bus this would configure the MAC + * on its own, for a link that cannot come up yet. + */ + if (phylink_slow_phy_pending(pl)) + return -EINVAL; + if (pl->phydev) { struct ethtool_link_ksettings phy_kset = *kset;
--
2.53.0