I'm now adding support for the Netgear GS110TPv3 which appears to have less multiplexing of the GPIO values used for SFP as follows:
====== Fiber =================
Fiber Port Number: 2
------------ Fiber Detect
LPort Present MediaChg OE Status LOS Status
------ -------- --------- ---------------------- ----------------------
8 OE OE Enabled (GPIO:EXT_14) Enabled (GPIO:EXT_7 )
9 OE OE Enabled (GPIO:EXT_13) Enabled (GPIO:EXT_6 )
------------ Fiber Optical
LPort I2C DEV I2C TYPE ID Delay SCK SDA
------ -------- --------- ----- ------- ------ ------
8 0 8 BITS 0x50 1000 EXT_36 EXT_28
9 1 8 BITS 0x50 1000 EXT_36 EXT_27
------------ Fiber TX Disable
LPort Method
------ ------
8 GPIO(EXT_9 )
9 GPIO(EXT_8 )
I've not used SFP modules on Linux before, so other than ensuring I have a link on the SFP port are there any diagnostic or utility programs I can use to verify the SFP is fully functional?