USBD_ENUMERATE_CFG
Purpose
Gets a list of Universal Serial Bus (USB) logical devices that are connected to a host controller.
Note: This
ioctl operation
is used only by the USB system device driver’s configuration
method.Syntax
int ioctl (file, USBD_ENUMERATE_CFG, arg)
Parameters
| Item | Description |
|---|---|
| file | File descriptor that is obtained when the USB system driver (USBD) special file was opened. |
| arg | Address of the USBENUMCFG structure
that is aligned with a 4-byte boundary. |
Description
This ioctl operation
behaves in the same manner as the USBD_ENUMERATE_DEVICE ioctl operation
except that it also returns the client device selection information.
The selection information uniquely identifies device-client pairing
and allows the configuration method to correlate enumerated devices
with their Object Data Manager (ODM) instances.
Execution environment
This function can be called from the user process environment only.
Return values
| Value | Description |
|---|---|
| 0 | Success. |
| -1 | Failure. Check the errno value for specific failure causes. |