xHCI spec is up!

I’m pleased to announce that the eXtensible Host Controller Interface (xHCI) 1.0 specification is now publicly available on intel.com. This is the specification for the PC hardware that talks to all your USB 3.0, USB 2.0, and USB 1.1 devices. (Yes, there are no more companion controllers, xHCI is the one host controller to rule them all).

Open, public documentation is always important to the open source community. Now that the spec is open, anyone can fully understand my Linux xHCI driver (although it’s currently only compliant to the 0.96 xHCI spec; anyone want to help fix that?). This also means the BSD developers can implement their own xHCI driver.

Curious what a TRB or a Set TR Deq Ptr command is? Want to know how device contexts or endpoint rings work? Go read the spec!