IOCTL_GET_PHYSICAL_DESCRIPTOR control code
The IOCTL_GET_PHYSICAL_DESCRIPTOR request obtains the physical descriptor of a top-level collection.
For general information about HIDClass devices, see HID Collections.
Parameters.DeviceIoControl.OutputBufferLength in the I/O stack location of the IRP indicates the size, in bytes, of the output buffer.
Irp->MdlAddress must point to the buffer that will receive the physical descriptor.
The HID class driver sets the Status member of Irp->IoStatus to STATUS_SUCCESS if the transfer completed without error. Otherwise, it is set to an appropriate NTSTATUS error code.