Subject: [PATCH net v2] net: sfp: Fix quirk for Ubiquiti U-Fiber Instant SFP module

From: Marek Behún <[email-masked]>
Date: Thu, 29 Jan 2026 09:22:27 +0100

Commit fd580c9830316eda ("net: sfp: augment SFP parsing with
phy_interface_t bitmap") did not add augumentation for the interface
bitmap in the quirk for Ubiquiti U-Fiber Instant.

The subsequent commit f81fa96d8a6c7a77 ("net: phylink: use
phy_interface_t bitmaps for optical modules") then changed phylink code
for selection of SFP interface: instead of using link mode bitmap, the
interface bitmap is used, and the fastest interface mode supported by
both SFP module and MAC is chosen.

Since the interface bitmap contains also modes faster than 1000base-x,
this caused a regression wherein this module stopped working
out-of-the-box.

Fix this.

Fixes: fd580c9830316eda ("net: sfp: augment SFP parsing with phy_interface_t bitmap")
Signed-off-by: Marek Behún <[email-masked]>
---
Changes since v1:
- use phy_interface_zero() instead of bitmap_zero(), as per Maxime's suggestion
---
 drivers/net/phy/sfp.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
index 47f095bd91ce..3e023723887c 100644
--- a/drivers/net/phy/sfp.c
+++ b/drivers/net/phy/sfp.c
@@ -479,6 +479,8 @@ static void sfp_quirk_ubnt_uf_instant(const struct sfp_eeprom_id *id,
 	linkmode_zero(caps->link_modes);
 	linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
 			 caps->link_modes);
+	phy_interface_zero(caps->interfaces);
+	__set_bit(PHY_INTERFACE_MODE_1000BASEX, caps->interfaces);
 }
 
 #define SFP_QUIRK(_v, _p, _s, _f) \
-- 
2.52.0