ChatGPT/dmesg output also made me aware that this downstream driver fork in #OpenWrt called ag71xx-legacy is not an up-to-date thing, supposedly using some old kernel interfaces? And that the original #ag71xx driver probably never got #SFP initialization stuff (so far). And I also couldn't find anything else with that driver in OpenWrt with an SFP port yet. So looks like one would need to compare some vendor C with what's in OpenWrt maybe. And should substitute some used kernel interfaces.
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