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USB_INTERFACE_DESCRIPTOR structure (usbspec.h)

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The USB_INTERFACE_DESCRIPTOR structure is used by USB client drivers to retrieve a USB-defined interface descriptor. The members of this structure are described in the Universal Serial Bus 3.1 Specification available at USB Document Library. See section 9.6.5.

Syntax

typedef struct _USB_INTERFACE_DESCRIPTOR {
  UCHAR bLength;
  UCHAR bDescriptorType;
  UCHAR bInterfaceNumber;
  UCHAR bAlternateSetting;
  UCHAR bNumEndpoints;
  UCHAR bInterfaceClass;
  UCHAR bInterfaceSubClass;
  UCHAR bInterfaceProtocol;
  UCHAR iInterface;
} USB_INTERFACE_DESCRIPTOR, *PUSB_INTERFACE_DESCRIPTOR;

Members

bLength

The length, in bytes, of the descriptor.

bDescriptorType

The descriptor type. bDescriptor must be set to USB_INTERFACE_DESCRIPTOR_TYPE.

bInterfaceNumber

The index number of the interface.

bAlternateSetting

The index number of the alternate setting of the interface.

bNumEndpoints

The number of endpoints that are used by the interface, excluding the default status endpoint.

bInterfaceClass

The class code of the device that the USB specification group assigned.

bInterfaceSubClass

The subclass code of the device that the USB specification group assigned.

bInterfaceProtocol

The protocol code of the device that the USB specification group assigned.

iInterface

The index of a string descriptor that describes the interface. For information about this field, see section 9.6.5 in the "Universal Serial Bus Revision 2.0" specification at USB Technology.

Requirements

Requirement Value
Header usbspec.h (include Usb100.h)

See also

USB Structures

UsbBuildGetDescriptorRequest

_URB_CONTROL_DESCRIPTOR_REQUEST