It seems during this year’s Google Summer of Code, one of the students over at React referred to Haiku’s XHCI stack to write an initial XHCI usb stack for react os. Blog posts here: https://www.reactos.org/blog/49141 This could help isn’t fix the problems with our own stack which student seems to have figured out. Congrats to you if you’re reading this by the way!
Thanks for the final link. I already read the blog posts in July, was interested in what was happening; the student was actually implementing the basic operations of the XHCI driver.
Problems with our own stack come after USB device initialization, which ReactOS still has to implement.