[PATCH net-next 01/13] net: phy: phy_port: Correctly recompute the port's linkmodes

Maxime Chevallier
2026-01-27T13:42:23Z

a PHY-driven phy_port contains a 'supported' field containing the
linkmodes available on this port. This is populated based on :
- The PHY's reported features
- The DT representation of the connector
- The PHY's attach_mdi() callback

As these different attrbutin methods work in conjunction, the helper
phy_port_update_supported() recomputes the final 'supported' value based
on the populated mediums, linkmodes and pairs.

However this recompute wasn't correctly implemented, and added more
modes than necessary by or'ing the medium-specific modes to the existing
support. Let's fix this and properly filter the modes.

Fixes: 589e934d2735 ("net: phy: Introduce PHY ports representation")
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
---
drivers/net/phy/phy_port.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/net/phy/phy_port.c b/drivers/net/phy/phy_port.c
index ec93c8ca051e..68a0068220ed 100644
--- a/drivers/net/phy/phy_port.c
+++ b/drivers/net/phy/phy_port.c
@@ -118,11 +118,14 @@ void phy_port_update_supported(struct phy_port *port)
int i;

for_each_set_bit(i, &port->mediums, __ETHTOOL_LINK_MEDIUM_LAST) {
- linkmode_zero(supported);
- phy_caps_medium_get_supported(supported, i, port->pairs);
- linkmode_or(port->supported, port->supported, supported);
+ __ETHTOOL_DECLARE_LINK_MODE_MASK(med_supported) = {0};
+
+ phy_caps_medium_get_supported(med_supported, i, port->pairs);
+ linkmode_or(supported, supported, med_supported);
}

+ linkmode_and(port->supported, port->supported, supported);
+
/* If there's no pairs specified, we grab the default number of
* pairs as the max of the default pairs for each linkmode
*/
--
2.49.0