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

NAME


usba_device, usba_device_t - USBA Device Data Structure

SYNOPSIS


#include <sys/usb/usba/hcdi.h>

INTERFACE LEVEL


Volatile - illumos USB HCD private

This is a private data structure that is not part of the stable DDI. It
may be removed or changed at any time.

DESCRIPTION


The usba_device_t structure is used by the illumos USB Architecture (USBA)
to represent a physical USB device. While a given USB device may be a
composite device, a USB device that implements two or more classes, there
will still only be a single device structure. A USB device is always
plugged into a port on some hub, excepting the root hub, and has an address
on the USB fabric.

Many of the USB HCD driver operations pass a usba_device_t to the HCD
driver. The usba_device_t should be used by an HCD driver in a read-only
fashion. A subset of the structure's fields that are useful for HCD
drivers to read are listed below.

In addition, there are two optional HCD entry points that interact with
this structure and give the change for a driver to store per-device state.
If the driver implements the usba_hcdi_device_init(9E) and
usba_hcdi_device_fini(9E) functions, then the private data stored from
usba_hcdi_device_init(9E) can be retrieved with
usba_hcdi_get_device_private(9F).

STRUCTURE MEMBERS


The usba_device_t structure includes the following members:

dev_info_t *usb_dip
usba_hubdi_t *usb_hubdi;
usb_addr_t usb_addr;
usb_dev_descr_t *usb_dev_descr;
char *usb_mfg_str;
char *usb_product_str;
char *usb_serialno_str;
usb_port_status_t usb_port_status;
usb_port_t usb_port;
usba_device_t *usb_hs_hub_usba_dev;
usba_device_t *usb_parent_hub;

The usb_dip member is a pointer to the device's dev_info_t structure. This
generally is used if the HCD driver wants to get naming information for
diagnostic purposes. When duplicating requests for isochronous and
interrupt requests, HCD drivers should use the dev_info_t from the
usba_pipe_handle_data_t(9S).

The usb_hubdi member can be used to determine whether or not the
usba_device_t in question is a hub or not. HCD drivers should compare this
member to NULL. If the member is not NULL, then this USB device
corresponds to a hub.

the usb_addr member indicates the address of the USB device on the broader
USB bus. Note, that the actual address assigned to the device may be
different, especially if the HCD driver implements the optional
usba_hcdi_device_address(9E) entry point. See the section USB addressing
in usba_hcdi(9E) for more information.

The usb_dev_descr member points to the device descriptor for a given
device. This structure is documented in usb_dev_descr(9S). This member
may be NULL as it may not have been populated during device attachment.
This member may be NULL. HCD drivers should always check for NULL before
dereferencing it.

The usb_mfg_str member may contain a pointer to a character string with the
name of the manufacturer as retrieved from the device. This member may be
NULL. HCD drivers should always check for NULL before dereferencing it.

The usb_product_str member may contain a pointer to a character string with
the name of the product as retrieved from the device. This member may be
NULL. HCD drivers should always check for NULL before dereferencing it.

The usb_serialno_str member may contain a pointer to a character string
with the serial number of the device as retrieved from the device. This
member may be NULL. HCD drivers should always check for NULL before
dereferencing it.

The usb_port_status contains a usb_port_status_t(9T) entry, which describes
the current negotiated speed of the device. See usb_port_status_t(9T) for
more information on the values and types.

The usb_port member contains the port on a hub that the device is plugged
into. Ports are always numbered starting at 1.

The usb_hs_hub_usba_dev member is set when there is a parent high-speed
hub. This is most notable for low- and full- speed devices which require
split transaction support. This points to the usb_device_t structure that
is the closest high-speed parent hub. This member should always be set to
NULL for super-speed devices. A device operating a super-speed can never
be plugged into a high-speed hub.

The usb_parent_hub member points to the usba_device_t structure that the
device in question is plugged into. If the device represents the root hub,
then this field will be NULL.

SEE ALSO


usba_hcdi(9E), usba_hcdi_device_address(9E), usba_hcdi_device_fini(9E),
usba_hcdi_device_init(9E), usba_pipe_handle_data_t(9S),
usb_port_status_t(9T)

illumos December 20, 2016 illumos