Intel Extensible Firmware Interface - Manual (Page 599)

Protocols — USB Support
Version 1.10 12/01/02 14-59
EFI_USB_IO_PROTOCOL.UsbGetEndpointDescriptor()
Summary
Retrieves an Endpoint Descriptor within a USB Controller.
Prototype
typedef
EFI_STATUS
(EFIAPI *EFI_USB_IO_GET_ENDPOINT_DESCRIPTOR) (
IN EFI_USB_IO_PROTOCOL
*This,
IN UINT8 EndpointIndex,
OUT EFI_USB_ENDPOINT_DESCRIPTOR *EndpointDescriptor
);
Parameters
This A pointer to the EFI_USB_IO_PROTOCOL instance. Type
EFI_USB_IO_PROTOCOL is defined in Section 14.2.5.
EndpointIndex Indicates which endpoint descriptor to retrieve. The valid
range is 0..15.
EndpointDescriptor A pointer to the caller allocated USB Endpoint Descriptor of
a USB controller. See “Related Definitions” for a detailed
description.
Related Definitions
//
// See USB1.1 for detail descrption.
//
typedef struct {
UINT8
Length;
UINT8 DescriptorType;
UINT8 EndpointAddress;
UINT8 Attributes;
UINT16 MaxPacketSize;
UINT8 Interval;
} EFI_USB_ENDPOINT_DESCRIPTOR;
Description
This function is used to retrieve an endpoint descriptor within a USB controller. If
EndpointIndex is not in the range 0..15, then EFI_INVALID_PARAMETER is returned. If
EndpointDescriptor is NULL , then EFI_INVALID_PARAMETER is returned. If the
endpoint specified by EndpointIndex does not exist within the USB controller, then
EFI_NOT_FOUND is returned. Otherwise, the endpoint descriptor is returned in
EndpointDescriptor , and EFI_SUCCESS is returned.