[BPI-R4] Enable PoE with RT5400

I recently bought and set up a BPi-R4 for its open approach with schematics and option’s galore. While a lot of features worked out of the box - thanks to a lot of work that has been put into openwrt by folks on this forum - I can’t figure out how to enable the PoE module which i recently soldered to the expansion contacts on the port. The closest I’ve gotten so far: The module might expect a GPIO pin to be set high for it to power on. Unfortunately the pin does not appear to be labeled in sysfs nor did i find the clue in the MT7988A manual. I did find out something about how the RT5400 is wired up in the schematics of the board on page 9. Unlike e.g. the green led for the lan ports, which is distinctly labeled as GPIO68_LED_E which translates to pad_led_e there is no easy way to see if the PoE is powered on or what i need to do in order to change that. Any help to make PoE work would be highly appreciated. I see that this dev board is not all plug and play - as expected. I am also willing to put my own elbow grease in. Please just point me in the right direction what to do or how i can help to make this feature work.


what do you want to do with this feature? I’m not sure about this topic, but I thought the POE module can only receive POE not supply. This is your usecase?

And this is how your R4 looks now?:

I found a discussion about it:

The person who wrote this mentioned, that you need two things:


→ RT5400 PoE

I am not 100% certain about the following statement, but I think it is true:

The reason you need to also solder on the RJ45 connector is that the POE is an input only via that port. None of the 4 ports grouped together receive or transmit POE.