Devices plugged into internal USB ports stop working after sleep, but external ports are fine

I'm still working on my Travelmate P645 that I posted about previously.

I was able to get sleep to work (finally) by blacklisting one single RTC address. I also upgraded to the current Big Sur.

Everything works fine, except one thing: when I put the machine to sleep, after wake, none of the devices plugged into internal USB ports work. This includes the Bluetooth and the webcam. There's also a fingerprint reader on the internal USB bus too, but that doesn't work anyway so no worries there. Even after sleep, I can still plug in devices to the externally visible ports and those devices work fine.

These internal USB devices all consistently work upon boot. I can see three internal USB devices in the System Profiler. I can also see using USBMap (which I used to create the USB map for the machine, as mentioned in my other post linked above) that the ports the devices are on are all set to be type 255. AFAIK, this is correct for internal ports.

Does anyone know what I should try here? Is it possible to do a software bus reset for the internal bus or something similar? Right now, I just have to reboot after sleep if I want to use BT or the webcam.