The Enhanced Host Controller Interface (EHCI) is standard for USB 2.0
"high speed" (480 Mbit/sec, 60 Mbyte/sec) host controller hardware.
If your USB host controller supports USB 2.0, you will likely want to
configure this Host Controller Driver. At the time of this writing,
the primary implementation of EHCI is a chip from NEC, widely available
in add-on PCI cards, but implementations are in the works from other
vendors including Intel and Philips. Motherboard support is appearing.

EHCI controllers are packaged with "companion" host controllers (OHCI
or UHCI) to handle USB 1.1 devices connected to root hub ports. Ports
will connect to EHCI if the device is high speed, otherwise they
connect to a companion controller. If you configure EHCI, you should
probably configure the OHCI (for NEC and some other vendors) USB Host
Controller Driver or UHCI (for Via motherboards) Host Controller
Driver too.

You may want to read Documentation/usb/ehci.txt.

To compile this driver as a module, choose M here: the
module will be called ehci-hcd.

source code:

drivers/usb/host/ehci-hcd.c