EHCI(4)                 NetBSD Kernel Interfaces Manual                EHCI(4)

NAME
     ehci -- USB Enhanced Host Controller driver

SYNOPSIS
     ehci* at cardbus? function ?
     ehci* at pci? dev ? function ?
     usb*  at ehci?

DESCRIPTION
     The ehci driver provides support for the USB Enhanced Host Controller
     Interface, which is used by USB 2.0 controllers.

     EHCI controllers are peculiar in that they can only handle the USB 2.0
     protocol.  This means that they normally have one or more companion con-
     trollers (i.e., ohci(4) or uhci(4)) handling USB 1.x devices.  Conse-
     quently each USB connector is electrically connected to two USB con-
     trollers.  The handling of this is totally automatic, but can be noticed
     since USB 1.x and USB 2.0 devices plugged in to the same connector appear
     to connect to different USB busses.

SEE ALSO
     cardbus(4), ohci(4), pci(4), uhci(4), usb(4)

HISTORY
     The ehci driver appeared in NetBSD 1.6.

BUGS
     The support for hubs that are connected with high speed upstream and low
     or full speed downstream (i.e., for transaction translators) is limited.

NetBSD 5.0_STABLE                Aug 10, 2008                NetBSD 5.0_STABLE
