IOCTL_GET_PHYSICAL_DESCRIPTOR IOCTL

Description

The IOCTL_GET_PHYSICAL_DESCRIPTOR request obtains the physical descriptor of a top-level collection. For a minidriver, this descriptor is the descriptor of the HIDClass device.

For general information about HIDClass devices, see HID Collections.

Parameters

Major code

Input buffer

Parameters.DeviceIoControl.OutputBufferLength in the I/O stack location of the IRP indicates the size, in bytes, of the output buffer.

Input buffer length

Output buffer

Irp->MdlAddress must point to the buffer that will receive the physical descriptor.

The HID minidriver copies the physical descriptor into the user buffer at Irp->UserBuffer.

Output buffer length

Input/output buffer

Input/output buffer length

Status block

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.

HID minidrivers that carry out the I/O to the device set the following fields of Irp->IoStatus:

• Information is set to the number of bytes transferred from the device.
• Status is set to STATUS_SUCCESS if the transfer completed without error. Otherwise, it is set to an appropriate NTSTATUS error code.

HID minidrivers that call other drivers with this IRP to carry out the I/O to their device should ensure that the Information field of the status block is correct and not change the contents of the Status field.

See also

HidD_GetPhysicalDescriptor