USBD_REGISTER_MULTI_HC
Purpose
Registers the Universal Serial Bus (USB) host controller with the USB system driver (USBD).
Syntax
int ioctl (file, USBD_REGISTER_MULTI_HC, arg)
Parameters
| Item | Description |
|---|---|
| file | File descriptor that is obtained when the USBD special file was opened. |
| arg | Pointer to the information structure of the USB host controller. |
Description
This ioctl operation
registers all the USB host controllers that are listed in the usb_adapterhc_info structure
with the USBD and allows the clients to communicate to the devices
that are connected to the controller. There is no specific ioctl operation
to unregister a hardware controller. It stays registered until either
the USBD is unconfigured or the host controller is unconfigured. In
the latter case, the host controller driver requests the USBD to unregister
the host controller through the usbdReqHCunregister call
vector. This ioctl operation must be invoked only
by the cfgusb configuration method during enumeration
and individual USB adapter configuration methods must use the USBD_REGISTER_SINGLE_HC operation
to register single host controller instance.
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. |