USB_DEV_QLF_DESCR(9S) Data Structures for Drivers USB_DEV_QLF_DESCR(9S)

usb_dev_qlf_descr - USB device qualifier descriptor

#include <sys/usb/usba.h>

illumos DDI specific (illumos DDI)

The device qualifier descriptor usb_dev_qlf_descr_t defines how fields of a high speed device's device descriptor would look if that device is run at a different speed. If a high-speed device is running currently at full/high speed, fields of this descriptor reflect how device descriptor fields would look if speed was changed to high/full. Please refer to section 9.6.2 of the USB 2.0 specification. The USB 2.0 specification is available at

A device descriptor contains the following fields:

uint8_t     bLength             Size of this descriptor.
uint8_t     bDescriptorType     Set to USB_DESCR_TYPE_DEV_QLF.
uint16_t    bcdUSB              USB specification release
                                number in binary coded decimal.
uint8_t     bDeviceClass        Device class code.
                                (See usb_dev_descr(9s).)
uint8_t     bDeviceSubClass     Device subclass code.(See
                                USB 2.0 specification of
                                applicable device class for
uint8_t     bDeviceProtocol     Protocol code.(See
                                USB 2.0 specification of
                                applicable device class for
uint8_t     bMaxPacketSize0     Maximum packet size of
                                endpoint 0.
uint8_t     bNumConfigurations  Number of available
uint8_t     bReserved           Reserved.

See attributes(7) for descriptions of the following attributes:

Architecture PCI-based systems
Interface stability Committed

attributes(7), usb_get_alt_if(9F), usb_get_cfg(9F), usb_get_dev_data(9F), usb_get_string_descr(9F), usb_parse_data(9F), usb_cfg_descr(9S), usb_ctrl_request(9S), usb_dev_descr(9S), usb_ep_descr(9S), usb_if_descr(9S), usb_other_speed_cfg_descr(9S), usb_string_descr(9S)
January 5, 2004 OmniOS