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Efi_usb_hc_protocol.getroothubportnumber(), Getroothubportnumber(), Efi_usb_hc_protocol.getroothubportnumber() summary – Intel Extensible Firmware Interface User Manual

Page 565: Prototype, Parameters, Description, Status codes returned

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Protocols

— USB Support

Version 1.10

12/01/02

14-25

EFI_USB_HC_PROTOCOL.GetRootHubPortNumber()

Summary

Retrieves the number of root hub ports.

Prototype

typedef
EFI_STATUS
(EFIAPI *EFI_USB_HC_PROTOCOL_GET_ROOTHUB_PORT_NUMBER) (
IN EFI_USB_HC_PROTOCOL

*This,

OUT UINT8

*PortNumber

);

Parameters

This

A pointer to the

EFI_USB_HC_PROTOCOL

instance. Type

EFI_USB_HC_PROTOCOL

is defined in Section 14.1.

PortNumber

A pointer to the number of the root hub ports.

Description

This function is used to retrieve the number of root hub ports. The number of root hub ports is
required by the USB bus driver to perform bus enumeration.

Status Codes Returned

EFI_SUCCESS

The port number was retrieved successfully.

EFI_INVALID_PARAMETER

PortNumber

is

NULL

.

EFI_DEVICE_ERROR

An error was encountered while attempting to retrieve the port number.