Hi

On 7/5/26 20:54, Martino Dell'Ambrogio wrote:

Cheap XGS-PON ONT sticks identifying as vendor "OEM", PN "XGSPONST2001"
have broken TX_FAULT and LOS indicators (driven by the ONU serial
passthrough wires) and need a longer T_START_UP than the SFF-8472
default. The Fiberstore XGS-SFP-ONT-MACI MAC-mode ONT stick has the
same ONT-class TX_FAULT/LOS wiring and startup behaviour. Apply the
existing sfp_fixup_potron handler to both, which masks both signals
and bumps T_START_UP to T_START_UP_BAD_GPON.

Both modules fail to space-pad the EEPROM vendor PN field past the
legitimate string as SFF-8472 mandates (the XGSPONST2001 fills it with
non-printable garbage), which defeats exact-length matching:
sfp_strlen() cannot trim the field, so a plain SFP_QUIRK_F entry would
silently never apply and the kernel would honor the spurious TX_FAULT
and eventually disable the module. Match both entries as prefixes
using SFP_QUIRK_F_PREFIX.

Signed-off-by: Martino Dell'Ambrogio <redacted>

Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>

Maxime