[EMAIL PROTECTED] wrote: >> I was under the impression that most if not all new USB controllers >> were OHCI and not UHCI. Perhaps that's just been my exposure. > > that's interesting. i thought that once myself last year, but > suddenly all the ones i see are UHCI/EHCI. perhaps there is a market > survey somewhere. > it doesn't really matter: there are many OHCI systems and it's > sensible to drive them. (and that's easier than the ndis wrapper FOR > THAT PURPOSE given > the nature of that code.)
My understanding: EHCI is an extension to UHCI to enable a much greater degree of buffering to support USB 2.0 data rates. Prior to USB 2.0, OHCI began to take over because of VIA's implementation being in so many chipsets, and it being available in 'soft' form and as a result appearing in a lot of SoC devices. Now that everything needs USB 2.0, and EHCI is the only register standard, perhaps it works out more economic to licence UHCI as it gets thrown in 'free' with EHCI? Just a guess.
