Another STM32 I've had for years is the Liveview.
A few clever people on the XDA developers forum have reverse engineered the device and made drivers for chibios.
The code is on github here ----> https://github.com/GottZ/olvfw FYI this is not my code!!
It's old code but I've compiled it my self and flashed it and it works!
And yes I'll be getting canbus working via the micro usb port at some point :)