[PATCH v2] net: sfp: add quirks for GPON ONT SFP sticks

[John Pavlick <jspavlick@posteo.net>]

Several GPON ONT SFP sticks based on Realtek RTL960x report
1000BASE-LX at 1300MBd in their EEPROM but can operate at 2500base-X.
On hosts with serdes fixed at 2.5Gbase-X (e.g. Banana Pi R3 / MT7986),
the kernel rejects them with 'no common interface modes'.

Add quirks for:
- Hisense-Leox LXT-010S-H
- Hisense ZNID-GPON-2311NA
- HSGQ HSGQ-XPON-Stick

Each quirk advertises 2500base-X and ignores TX_FAULT during the
module's ~40s Linux boot time.

Tested on Banana Pi R3 (MT7986) with OpenWrt 25.12.1, confirmed
2.5Gbps link and full throughput with flow offloading.

Suggested-by: Marcin Nita <marcin.nita@leolabs.pl>
Signed-off-by: John Pavlick <jspavlick@posteo.net>
---
Changes in v2:
  - Add Suggested-by tag for Marcin Nita <marcin.nita@leolabs.pl>, who
    suggested investigating sfp.c quirks as a solution rather than
    attempting to edit the EEPROM data directly on the module.

 drivers/net/phy/sfp.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c
index f1070eb0a0bb..bd970f753beb 100644
--- a/drivers/net/phy/sfp.c
+++ b/drivers/net/phy/sfp.c
@@ -543,6 +543,22 @@ static const struct sfp_quirk sfp_quirks[] = {
 	SFP_QUIRK("HUAWEI", "MA5671A", sfp_quirk_2500basex,
 		  sfp_fixup_ignore_tx_fault_and_los),
 
+	// Hisense LXT-010S-H is a GPON ONT SFP (sold as LEOX LXT-010S-H) that
+	// can operate at 2500base-X, but reports 1000BASE-LX / 1300MBd in its
+	// EEPROM
+	SFP_QUIRK("Hisense-Leox", "LXT-010S-H", sfp_quirk_2500basex,
+		  sfp_fixup_ignore_tx_fault),
+
+	// Hisense ZNID-GPON-2311NA can operate at 2500base-X, but reports
+	// 1000BASE-LX / 1300MBd in its EEPROM
+	SFP_QUIRK("Hisense", "ZNID-GPON-2311NA", sfp_quirk_2500basex,
+		  sfp_fixup_ignore_tx_fault),
+
+	// HSGQ HSGQ-XPON-Stick can operate at 2500base-X, but reports
+	// 1000BASE-LX / 1300MBd in its EEPROM
+	SFP_QUIRK("HSGQ", "HSGQ-XPON-Stick", sfp_quirk_2500basex,
+		  sfp_fixup_ignore_tx_fault),
+
 	// Lantech 8330-262D-E and 8330-265D can operate at 2500base-X, but
 	// incorrectly report 2500MBd NRZ in their EEPROM.
 	// Some 8330-265D modules have inverted LOS, while all of them report
-- 
2.53.0