Intel Extensible Firmware Interface - Manual (Page 543)

Protocols — USB Support
Version 1.10 12/01/02 14-3
BulkTransfer Submits a bulk transfer to a bulk endpoint of a USB device. See
the
BulkTransfer() function description.
AsyncInterruptTransfer
Submits an asynchronous interrupt transfer to an interrupt endpoint
of a USB device. See the
AsyncInterruptTransfer()
function description.
SyncInterruptTransfer
Submits a synchronous interrupt transfer to an interrupt endpoint
of a USB device. See the
SyncInterruptTransfer()
function description.
IsochronousTransfer Submits isochronous transfer to an isochronous endpoint of a USB
device. See the
IsochronousTransfer() function
description.
AsyncIsochronousTransfer
Submits nonblocking USB isochronous transfer. See the
AsyncIsochronousTransfer() function description.
GetRootHubPortNumber Retrieves the number of root hub ports that are produced by the
USB host controller. See the GetRootHubPortNumber()
function description.
GetRootHubPortStatus Retrieves the status of the specified root hub port. See the
GetRootHubPortStatus() function description.
SetRootHubPortFeature
Sets the feature for the specified root hub port. See the
SetRootHubPortFeature() function description.
ClearRootHubPortFeature
Clears the feature for the specified root hub port. See the
ClearRootHubPortFeature() function description.
MajorRevision The major revision number of the USB host controller. The
revision information indicates the release of the Universal Serial
Bus Specification with which the host controller is compliant.
MinorRevision The minor revision number of the USB host controller. The
revision information indicates the release of the Universal Serial
Bus Specification with which the host controller is compliant.
Description
The EFI_USB_HC_PROTOCOL provides USB host controller management, basic data transactions
over a USB bus, and USB root hub access. A device driver that wishes to manage a USB bus in a
system retrieves the
EFI_USB_HC_PROTOCOL instance that is associated with the USB bus to be
managed. A device handle for a USB host controller will minimally contain an
EFI_DEVICE_PATH_PROTOCOL instance, and an EFI_USB_HC_PROTOCOL instance.