Raspberry PI 5 with Build HAT power issues

[dslate]

I have a Raspberry PI 5, plus the Build HAT for connecting Lego motors and sensors, and the official 48W Build HAT power supply. The system is up and running and successfully ran some sensor and motor tests. But every time I boot up, I get this message at the top right of my screen: "This power supply is not capable of supplying 5A. Power to peripherals will be restricted". So far I have figured out that the problem is that the PI 5 needs to do PD negotiation with its power supply, which can't be done when power is supplied via the Build HAT. There seems to be a workaround that involves editing the PSU_MAX_CURRENT value in the PI 5 Bootloader configuration file to skip PD negotiation. I haven't tried that yet, and thought I should ask if there is a more "canonical" way to deal with this problem, if it is indeed a problem (I haven't yet tried to connect USB peripherals with heavy current requirements). Anyone out there with experience using the Build HAT with a PI 5 who can suggest a solution to this issue? Thanks.

[JopieK]

Hmm, interest problem indeed. The Pi 5 power management is at least much better than that of the Pi 4.

You probably already saw this topic? https://forums.raspberrypi.com/viewtopic.php?t=359911

(Adjusting the USB Current Limit could be an alternative but it is as 'canonical' as the PSU_MAX_CURRENT route I guess).

[dslate]

Thanks JopieK. Yes, I have seen that post. I may decide to add PSU_MAX_CURRENT=5000 to the eeprom config as suggested, but years of experience with Linux systems (mostly Ubuntu) have taught be to be cautious about modifying anything connected with the bootloader, for fear of badly screwing up something. I'm hoping someone who has actually used the Build HAT with a PI 5 will weigh in with some sage advice.

Edited January 9 by dslate
small typo