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IOCTL_INTERNAL_USB_GET_CONTROLLER_NAME IOCTL (usbioctl.h)

The IOCTL_INTERNAL_USB_GET_CONTROLLER_NAME I/O request queries the bus driver for the device name of the USB host controller.

IOCTL_INTERNAL_USB_GET_CONTROLLER_NAME is a kernel-mode I/O control request. This request targets the USB hub PDO. This request must be sent at an IRQL of PASSIVE_LEVEL.

Major code

IRP_MJ_INTERNAL_DEVICE_CONTROL

Input buffer

Parameters.Others.Argument1 should be a pointer to a USB_HUB_NAME structure that will be filled in with the name of the host controller.

Input buffer length

Parameters.Others.Argument2 should be a ULONG specifying the length of the buffer (in bytes) in Parameters.Others.Argument1.

Output buffer

The bus driver will fill the buffer pointed to by Parameters.Others.Argument1 with the host controller device name.

Output buffer length

It will be filled only up to the length specified in Parameters.Others.Argument2.

Status block

The bus or port driver sets Irp->IoStatus.Status to STATUS_SUCCESS or the appropriate error status.

Remarks

The caller must supply a buffer that is large enough to hold a USB_HUB_NAME structure. The Parameters.Others.Argument2 value indicates size of that buffer. Upon successful completion, the HubName member of USB_HUB_NAME contains the name of the controller and the ActualLength member indicates the length of the controller name string. Note that ActualLength does not indicate the size of the entire USB_HUB_NAME structure. If the buffer supplied in Parameters.Others.Argument1 is not large enough to hold the string, the HubName value might show a truncated string.

To obtain the size of the buffer required to hold the string, send the request twice. In the first request, specify a buffer that is at least sizeof(USB_HUB_NAME) bytes. Otherwise, ActualLength does not indicate the correct length of the string and the request fails with STATUS_BUFFER_TOO_SMALL.

After the first request completes successfully, allocate a buffer of ActualLength + sizeof(ULONG) bytes and send the request again. After the request completes, HubName indicates the entire controller name string.

Requirements

Requirement Value
Header usbioctl.h

See also

USB_HUB_NAME