windows-server-2003/drivers/wdm/usb/driver/i82930/sys/i82930.c

/*++

Copyright (c) 1996-1998 Microsoft Corporation

Module Name:

    I82930.C

Abstract:

    This source file contains the DriverEntry() and AddDevice() entry points
    for the I82930 driver and the dispatch routines which handle:

    IRP_MJ_POWER
    IRP_MJ_SYSTEM_CONTROL
    IRP_MJ_PNP

Environment:

    kernel mode

Revision History:

    06-01-98 : started rewrite

--*/

//*****************************************************************************
// I N C L U D E S
//*****************************************************************************

#include <wdm.h>
#include <usbdi.h>
#include <usbdlib.h>

#include <initguid.h>

#include "i82930.h"
#include "ioctl.h"

#ifdef ALLOC_PRAGMA
#pragma alloc_text(PAGE, DriverEntry)
#pragma alloc_text(PAGE, I82930_Unload)
#pragma alloc_text(PAGE, I82930_AddDevice)
#pragma alloc_text(PAGE, I82930_Power)
#pragma alloc_text(PAGE, I82930_SystemControl)
#pragma alloc_text(PAGE, I82930_Pnp)
#pragma alloc_text(PAGE, I82930_StartDevice)
#pragma alloc_text(PAGE, I82930_StopDevice)
#pragma alloc_text(PAGE, I82930_RemoveDevice)
#pragma alloc_text(PAGE, I82930_QueryStopRemoveDevice)
#pragma alloc_text(PAGE, I82930_CancelStopRemoveDevice)
#pragma alloc_text(PAGE, I82930_QueryCapabilities)
#pragma alloc_text(PAGE, I82930_SyncPassDownIrp)
#pragma alloc_text(PAGE, I82930_SyncSendUsbRequest)
#pragma alloc_text(PAGE, I82930_GetDescriptor)
#pragma alloc_text(PAGE, I82930_SelectConfiguration)
#pragma alloc_text(PAGE, I82930_UnConfigure)
#endif

//******************************************************************************
//
// DriverEntry()
//
//******************************************************************************

NTSTATUS
DriverEntry (
    IN PDRIVER_OBJECT   DriverObject,
    IN PUNICODE_STRING  RegistryPath
    )
{
#if DBG
    // Query the registry for global parameters
    //
    I82930_QueryGlobalParams();
#endif

    DBGPRINT(2, ("enter: DriverEntry\n"));

    DBGFBRK(DBGF_BRK_DRIVERENTRY);

    LOGINIT();

    //
    // Initialize the Driver Object with the driver's entry points
    //

    //
    // I82930.C
    //
    DriverObject->DriverUnload                          = I82930_Unload;
    DriverObject->DriverExtension->AddDevice            = I82930_AddDevice;

    //
    // OCRW.C
    //
    DriverObject->MajorFunction[IRP_MJ_CREATE]          = I82930_Create;
    DriverObject->MajorFunction[IRP_MJ_CLOSE]           = I82930_Close;
    DriverObject->MajorFunction[IRP_MJ_READ]            = I82930_ReadWrite;
    DriverObject->MajorFunction[IRP_MJ_WRITE]           = I82930_ReadWrite;

    //
    // IOCTL.C
    //
    DriverObject->MajorFunction[IRP_MJ_DEVICE_CONTROL]  = I82930_DeviceControl;

    //
    // I82930.C
    //
    DriverObject->MajorFunction[IRP_MJ_POWER]           = I82930_Power;
    DriverObject->MajorFunction[IRP_MJ_SYSTEM_CONTROL]  = I82930_SystemControl;
    DriverObject->MajorFunction[IRP_MJ_PNP]             = I82930_Pnp;

    DBGPRINT(2, ("exit:  DriverEntry\n"));

    return STATUS_SUCCESS;
}

//******************************************************************************
//
// I82930_Unload()
//
//******************************************************************************

VOID
I82930_Unload (
    IN PDRIVER_OBJECT   DriverObject
    )
{
    DBGPRINT(2, ("enter: I82930_Unload\n"));

    LOGENTRY('UNLD', DriverObject, 0, 0);

    DBGFBRK(DBGF_BRK_UNLOAD);

    LOGUNINIT();

    DBGPRINT(2, ("exit:  I82930_Unload\n"));
}

//******************************************************************************
//
// I82930_AddDevice()
//
//******************************************************************************

NTSTATUS
I82930_AddDevice (
    IN PDRIVER_OBJECT   DriverObject,
    IN PDEVICE_OBJECT   PhysicalDeviceObject
    )
{
    NTSTATUS            ntStatus;
    PDEVICE_OBJECT      deviceObject;
    PDEVICE_EXTENSION   deviceExtension;

    DBGPRINT(2, ("enter: I82930_AddDevice\n"));

    LOGENTRY('ADDD', DriverObject, PhysicalDeviceObject, 0);

    DBGFBRK(DBGF_BRK_ADDDEVICE);

    // Create the FDO
    //
    ntStatus = IoCreateDevice(DriverObject,
                              sizeof(DEVICE_EXTENSION),
                              NULL,
                              FILE_DEVICE_UNKNOWN,
                              FILE_AUTOGENERATED_DEVICE_NAME,
                              FALSE,
                              &deviceObject);

    if (!NT_SUCCESS(ntStatus))
    {
        return ntStatus;
    }

    // Initialize the DeviceExtension
    //
    deviceExtension = deviceObject->DeviceExtension;

    // Set all DeviceExtension pointers to NULL and all variable to zero
    //
    RtlZeroMemory(deviceExtension, sizeof(DEVICE_EXTENSION));

    // Remember our PDO
    //
    deviceExtension->PhysicalDeviceObject = PhysicalDeviceObject;

    // Attach the FDO we created to the top of the PDO stack
    //
    deviceExtension->StackDeviceObject = IoAttachDeviceToDeviceStack(
                                             deviceObject,
                                             PhysicalDeviceObject);

    // Initialize to one in AddDevice, decrement by one in REMOVE_DEVICE
    //
    deviceExtension->OpenCount = 1;

    // Initialize the event which is set when OpenCount is decremented to zero.
    //
    KeInitializeEvent(&deviceExtension->RemoveEvent,
                      SynchronizationEvent,
                      FALSE);

    // Set the initial system and device power states
    //
    deviceExtension->SystemPowerState = PowerSystemWorking;
    deviceExtension->DevicePowerState = PowerDeviceD0;

    deviceObject->Flags |=  DO_DIRECT_IO;
    deviceObject->Flags |=  DO_POWER_PAGABLE;
    deviceObject->Flags &= ~DO_DEVICE_INITIALIZING;

    DBGPRINT(2, ("exit:  I82930_AddDevice\n"));

    LOGENTRY('addd', deviceObject, deviceExtension, deviceExtension->StackDeviceObject);

    return STATUS_SUCCESS;
}

//******************************************************************************
//
// I82930_Power()
//
// Dispatch routine which handles IRP_MJ_POWER
//
//******************************************************************************

NTSTATUS
I82930_Power (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    PDEVICE_EXTENSION       deviceExtension;
    PIO_STACK_LOCATION      irpStack;
    NTSTATUS                ntStatus;

    PAGED_CODE();

    deviceExtension = DeviceObject->DeviceExtension;

    irpStack = IoGetCurrentIrpStackLocation(Irp);

    DBGPRINT(2, ("enter: I82930_Power %08X %s\n",
                 DeviceObject,
                 PowerMinorFunctionString(irpStack->MinorFunction)));

    LOGENTRY('POWR', DeviceObject, Irp, irpStack->MinorFunction);

    if (irpStack->MinorFunction == IRP_MN_SET_POWER)
    {
        DBGPRINT(2, ("IRP_MN_SET_POWER %s\n",
                     (irpStack->Parameters.Power.Type == SystemPowerState) ?
                     PowerSystemStateString(irpStack->Parameters.Power.State.SystemState) :
                     PowerDeviceStateString(irpStack->Parameters.Power.State.DeviceState)));
    }

    if (irpStack->MinorFunction == IRP_MN_SET_POWER)
    {
        // Handle powering the FDO down and up...
        //
        ntStatus = I82930_FdoSetPower(DeviceObject,
                                      Irp);
    }
    else
    {
        // No special processing for IRP_MN_QUERY_POWER, IRP_MN_WAIT_WAKE,
        // or IRP_MN_POWER_SEQUENCE at this time.  Just pass the request
        // down to the next lower driver now.
        //
        PoStartNextPowerIrp(Irp);

        IoSkipCurrentIrpStackLocation(Irp);

        ntStatus = PoCallDriver(deviceExtension->StackDeviceObject,
                                Irp);
    }

    DBGPRINT(2, ("exit:  I82930_Power %08X\n", ntStatus));

    LOGENTRY('powr', ntStatus, 0, 0);

    return ntStatus;
}

//******************************************************************************
//
// I82930_FdoSetPower()
//
// Dispatch routine which handles IRP_MJ_POWER, IRP_MN_SET_POWER for the FDO
//
//******************************************************************************

NTSTATUS
I82930_FdoSetPower (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    PDEVICE_EXTENSION       deviceExtension;
    PIO_STACK_LOCATION      irpStack;
    POWER_STATE_TYPE        powerType;
    POWER_STATE             powerState;
    POWER_STATE             newState;
    BOOLEAN                 passRequest;
    NTSTATUS                ntStatus;

    PAGED_CODE();

    deviceExtension = DeviceObject->DeviceExtension;

    // Get our Irp parameters
    //
    irpStack = IoGetCurrentIrpStackLocation(Irp);

    powerType = irpStack->Parameters.Power.Type;

    powerState = irpStack->Parameters.Power.State;

    DBGPRINT(2, ("enter: I82930_FdoSetPower %08X %s\n",
                 DeviceObject,
                 (powerType == SystemPowerState) ?
                 PowerSystemStateString(powerState.SystemState) :
                 PowerDeviceStateString(powerState.DeviceState)));

    LOGENTRY('FDSP', DeviceObject, Irp, irpStack->MinorFunction);

    // Pass the request down here, unless we request a device state power
    // Irp, in which case we pass the request down in our completion routine.
    //
    passRequest = TRUE;

    if (powerType == SystemPowerState)
    {
        // Remember the current system state.
        //
        deviceExtension->SystemPowerState = powerState.SystemState;

        // Map the new system state to a new device state
        //
        if (powerState.SystemState != PowerSystemWorking)
        {
            newState.DeviceState = PowerDeviceD3;
        }
        else
        {
            newState.DeviceState = PowerDeviceD0;
        }

        // If the new device state is different than the current device
        // state, request a device state power Irp.
        //
        if (deviceExtension->DevicePowerState != newState.DeviceState)
        {
            DBGPRINT(2, ("Requesting power Irp %08X %08X from %s to %s\n",
                         DeviceObject, Irp,
                         PowerDeviceStateString(deviceExtension->DevicePowerState),
                         PowerDeviceStateString(newState.DeviceState)));

            ASSERT(deviceExtension->CurrentPowerIrp == NULL);

            deviceExtension->CurrentPowerIrp = Irp;

            ntStatus = PoRequestPowerIrp(deviceExtension->PhysicalDeviceObject,
                                         IRP_MN_SET_POWER,
                                         newState,
                                         I82930_FdoSetPowerCompletion,
                                         DeviceObject,
                                         NULL);

            passRequest = FALSE;
        }
    }
    else if (powerType == DevicePowerState)
    {
        POWER_STATE oldState;

        DBGPRINT(2, ("Received power Irp %08X %08X from %s to %s\n",
                     DeviceObject, Irp,
                     PowerDeviceStateString(deviceExtension->DevicePowerState),
                     PowerDeviceStateString(powerState.DeviceState)));

        // Update the current device state.
        //
        oldState.DeviceState = deviceExtension->DevicePowerState;
        deviceExtension->DevicePowerState = powerState.DeviceState;

        if (oldState.DeviceState == PowerDeviceD0 &&
            powerState.DeviceState > PowerDeviceD0)
        {
            // Powering down.

            DBGPRINT(2, ("FDO Powering Down\n"));

            LOGENTRY('PWRD', DeviceObject, Irp, 0);
        }
        else if (oldState.DeviceState > PowerDeviceD0 &&
                 powerState.DeviceState == PowerDeviceD0)
        {
            DBGPRINT(2, ("PDO Powering Up\n"));

            LOGENTRY('PWRU', DeviceObject, Irp, 0);
        }
    }

    if (passRequest)
    {
        //
        // Pass the request down to the next lower driver
        //
        PoStartNextPowerIrp(Irp);

        IoSkipCurrentIrpStackLocation(Irp);

        ntStatus = PoCallDriver(deviceExtension->StackDeviceObject,
                                Irp);
    }

    DBGPRINT(2, ("exit:  I82930_FdoSetPower %08X\n", ntStatus));

    LOGENTRY('fdsp', ntStatus, 0, 0);

    return ntStatus;
}

//******************************************************************************
//
// I82930_FdoSetPowerCompletion()
//
// Completion routine for PoRequestPowerIrp() in I82930_FdoSetPower.
//
// The purpose of this routine is to block passing down the SystemPowerState
// Irp until the requested DevicePowerState Irp completes.
//
//******************************************************************************

VOID
I82930_FdoSetPowerCompletion(
    IN PDEVICE_OBJECT   PdoDeviceObject,
    IN UCHAR            MinorFunction,
    IN POWER_STATE      PowerState,
    IN PVOID            Context,
    IN PIO_STATUS_BLOCK IoStatus
    )
{
    PDEVICE_OBJECT          fdoDeviceObject;
    PDEVICE_EXTENSION       deviceExtension;
    PIRP                    irp;
    NTSTATUS                ntStatus;

    fdoDeviceObject = (PDEVICE_OBJECT)Context;

    deviceExtension = fdoDeviceObject->DeviceExtension;

    ASSERT(deviceExtension->CurrentPowerIrp != NULL);

    irp = deviceExtension->CurrentPowerIrp;

    deviceExtension->CurrentPowerIrp = NULL;

#if DBG
    {
        PIO_STACK_LOCATION  irpStack;
        SYSTEM_POWER_STATE  systemState;

        irpStack = IoGetCurrentIrpStackLocation(irp);

        systemState = irpStack->Parameters.Power.State.SystemState;

        ntStatus = IoStatus->Status;

        DBGPRINT(2, ("I82930_FdoSetPowerCompletion %08X %08X %s %08X\n",
                     fdoDeviceObject, irp,
                     PowerSystemStateString(systemState),
                     ntStatus));

        LOGENTRY('fspc', fdoDeviceObject, systemState, ntStatus);
    }
#endif

    // The requested DevicePowerState Irp has completed.
    // Now pass down the SystemPowerState Irp which requested the
    // DevicePowerState Irp.

    PoStartNextPowerIrp(irp);

    IoSkipCurrentIrpStackLocation(irp);

    ntStatus = PoCallDriver(deviceExtension->StackDeviceObject,
                            irp);
}

//******************************************************************************
//
// I82930_SystemControl()
//
// Dispatch routine which handles IRP_MJ_SYSTEM_CONTROL
//
//******************************************************************************

NTSTATUS
I82930_SystemControl (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    NTSTATUS            ntStatus;
    PDEVICE_EXTENSION   deviceExtension;
    PIO_STACK_LOCATION  irpStack;

    deviceExtension = DeviceObject->DeviceExtension;

    irpStack = IoGetCurrentIrpStackLocation(Irp);

    DBGPRINT(2, ("enter: I82930_SystemControl %2X\n", irpStack->MinorFunction));

    LOGENTRY('SYSC', DeviceObject, Irp, irpStack->MinorFunction);

    switch (irpStack->MinorFunction)
    {
        //
        // XXXXX Need to handle any of these?
        //

        default:
            //
            // Pass the request down to the next lower driver
            //
            IoSkipCurrentIrpStackLocation(Irp);

            ntStatus = IoCallDriver(deviceExtension->StackDeviceObject,
                                    Irp);
            break;
    }

    DBGPRINT(2, ("exit:  I82930_SystemControl %08X\n", ntStatus));

    LOGENTRY('sysc', ntStatus, 0, 0);

    return ntStatus;
}

//******************************************************************************
//
// I82930_Pnp()
//
// Dispatch routine which handles IRP_MJ_PNP
//
//******************************************************************************

NTSTATUS
I82930_Pnp (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    NTSTATUS            ntStatus;
    PDEVICE_EXTENSION   deviceExtension;
    PIO_STACK_LOCATION  irpStack;

    deviceExtension = DeviceObject->DeviceExtension;

    irpStack = IoGetCurrentIrpStackLocation(Irp);

    DBGPRINT(2, ("enter: I82930_Pnp %s\n",
                 PnPMinorFunctionString(irpStack->MinorFunction)));

    LOGENTRY('PNP ', DeviceObject, Irp, irpStack->MinorFunction);

    switch (irpStack->MinorFunction)
    {
        case IRP_MN_START_DEVICE:
            ntStatus = I82930_StartDevice(DeviceObject, Irp);
            break;

        case IRP_MN_STOP_DEVICE:
            ntStatus = I82930_StopDevice(DeviceObject, Irp);
            break;

        case IRP_MN_REMOVE_DEVICE:
            ntStatus = I82930_RemoveDevice(DeviceObject, Irp);
            break;

        case IRP_MN_QUERY_STOP_DEVICE:
        case IRP_MN_QUERY_REMOVE_DEVICE:
            ntStatus = I82930_QueryStopRemoveDevice(DeviceObject, Irp);
            break;

        case IRP_MN_CANCEL_STOP_DEVICE:
        case IRP_MN_CANCEL_REMOVE_DEVICE:
            ntStatus = I82930_CancelStopRemoveDevice(DeviceObject, Irp);
            break;

        case IRP_MN_QUERY_CAPABILITIES:
            ntStatus = I82930_QueryCapabilities(DeviceObject, Irp);
            break;

        case IRP_MN_SURPRISE_REMOVAL:
            // nothing special yet, just fall through to default

        default:
            //
            // Pass the request down to the next lower driver
            //
            IoSkipCurrentIrpStackLocation(Irp);

            ntStatus = IoCallDriver(deviceExtension->StackDeviceObject,
                                    Irp);
            break;
    }

    DBGPRINT(2, ("exit:  I82930_Pnp %08X\n", ntStatus));

    LOGENTRY('pnp ', ntStatus, 0, 0);

    return ntStatus;
}


//******************************************************************************
//
// I82930_StartDevice()
//
// This routine handles IRP_MJ_PNP, IRP_MN_START_DEVICE
//
// The PnP Manager sends this IRP at IRQL PASSIVE_LEVEL in the context of a
// system thread.
//
// This IRP must be handled first by the underlying bus driver for a device
// and then by each higher driver in the device stack.
//
// Device specific actions:
//     Retrieve the Device Descriptor from device (first time only)
//     Retrieve the Configuration Descriptor from device (first time only)
//     Configure the device (every time)
//     Create the SymbolicLink name (first time only)
//     Enable the SymbolicLink name (every time)
//
//******************************************************************************

NTSTATUS
I82930_StartDevice (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    PDEVICE_EXTENSION   deviceExtension;
    PUCHAR              descriptor;
    ULONG               descriptorLength;
    NTSTATUS            ntStatus;

    DBGPRINT(2, ("enter: I82930_StartDevice\n"));

    DBGFBRK(DBGF_BRK_STARTDEVICE);

    LOGENTRY('STRT', DeviceObject, Irp, 0);

    deviceExtension = DeviceObject->DeviceExtension;

    // Pass IRP_MN_START_DEVICE Irp down the stack first before we do anything.
    //
    ntStatus = I82930_SyncPassDownIrp(DeviceObject,
                                      Irp,
                                      TRUE);
    if (!NT_SUCCESS(ntStatus))
    {
        DBGPRINT(1, ("Lower driver failed IRP_MN_START_DEVICE\n"));
        goto I82930_StartDeviceDone;
    }

    //
    // If this is the first time the device as been started, retrieve the
    // Device and Configuration Descriptors from the device.
    //
    if (deviceExtension->DeviceDescriptor == NULL)
    {
        //
        // Get Device Descriptor
        //
        ntStatus = I82930_GetDescriptor(DeviceObject,
                                        USB_RECIPIENT_DEVICE,
                                        USB_DEVICE_DESCRIPTOR_TYPE,
                                        0,  // Index
                                        0,  // LanguageId
                                        2,  // RetryCount
                                        sizeof(USB_DEVICE_DESCRIPTOR),
                                        &descriptor);

        if (!NT_SUCCESS(ntStatus))
        {
            DBGPRINT(1, ("Get Device Descriptor failed\n"));
            Irp->IoStatus.Status = ntStatus;
            goto I82930_StartDeviceDone;
        }

        deviceExtension->DeviceDescriptor = (PUSB_DEVICE_DESCRIPTOR)descriptor;

        //
        // Get Configuration Descriptor (just the Configuration Descriptor)
        //
        ntStatus = I82930_GetDescriptor(DeviceObject,
                                        USB_RECIPIENT_DEVICE,
                                        USB_CONFIGURATION_DESCRIPTOR_TYPE,
                                        0,  // Index
                                        0,  // LanguageId
                                        2,  // RetryCount
                                        sizeof(USB_CONFIGURATION_DESCRIPTOR),
                                        &descriptor);

        if (!NT_SUCCESS(ntStatus))
        {
            DBGPRINT(1, ("Get Configuration Descriptor failed (1)\n"));
            Irp->IoStatus.Status = ntStatus;
            goto I82930_StartDeviceDone;
        }

        descriptorLength = ((PUSB_CONFIGURATION_DESCRIPTOR)descriptor)->wTotalLength;

        ExFreePool(descriptor);

        if (descriptorLength < sizeof(USB_CONFIGURATION_DESCRIPTOR))
        {
            ntStatus = STATUS_DEVICE_DATA_ERROR;
            DBGPRINT(1, ("Get Configuration Descriptor failed (2)\n"));
            Irp->IoStatus.Status = ntStatus;
            goto I82930_StartDeviceDone;
        }

        //
        // Get Configuration Descriptor (and Interface and Endpoint Descriptors)
        //
        ntStatus = I82930_GetDescriptor(DeviceObject,
                                        USB_RECIPIENT_DEVICE,
                                        USB_CONFIGURATION_DESCRIPTOR_TYPE,
                                        0,  // Index
                                        0,  // LanguageId
                                        2,  // RetryCount
                                        descriptorLength,
                                        &descriptor);

        if (!NT_SUCCESS(ntStatus))
        {
            DBGPRINT(1, ("Get Configuration Descriptor failed (3)\n"));
            Irp->IoStatus.Status = ntStatus;
            goto I82930_StartDeviceDone;
        }

        deviceExtension->ConfigurationDescriptor = (PUSB_CONFIGURATION_DESCRIPTOR)descriptor;

#if DBG
        DumpDeviceDesc(deviceExtension->DeviceDescriptor);
        DumpConfigDesc(deviceExtension->ConfigurationDescriptor);
#endif
    }

    // Now configure the device
    //
    ntStatus = I82930_SelectConfiguration(DeviceObject);

    if (!NT_SUCCESS(ntStatus))
    {
        DBGPRINT(1, ("Configure device failed\n"));
        Irp->IoStatus.Status = ntStatus;
        goto I82930_StartDeviceDone;
    }

    // Create the SymbolicLink name if necessary
    //
    if (deviceExtension->SymbolicLinkName.Buffer == NULL)
    {
        ntStatus = IoRegisterDeviceInterface(
                       deviceExtension->PhysicalDeviceObject,
                       (LPGUID)&GUID_CLASS_I82930,
                       NULL,
                       &deviceExtension->SymbolicLinkName);

        if (!NT_SUCCESS(ntStatus))
        {
            DBGPRINT(1, ("IoRegisterDeviceInterface failed\n"));
            Irp->IoStatus.Status = ntStatus;
            goto I82930_StartDeviceDone;
        }
    }

    // All set for user requests at this point
    //
    deviceExtension->AcceptingRequests = TRUE;

    // Enable the SymbolicLink name
    //
    ntStatus = IoSetDeviceInterfaceState(
                   &deviceExtension->SymbolicLinkName,
                   TRUE);

    if (!NT_SUCCESS(ntStatus))
    {
        DBGPRINT(1, ("IoSetDeviceInterfaceState failed\n"));
        Irp->IoStatus.Status = ntStatus;
        goto I82930_StartDeviceDone;
    }

I82930_StartDeviceDone:

    // Must complete request since completion routine returned
    // STATUS_MORE_PROCESSING_REQUIRED
    //
    IoCompleteRequest(Irp, IO_NO_INCREMENT);

    DBGPRINT(2, ("exit:  I82930_StartDevice %08X\n", ntStatus));

    LOGENTRY('strt', ntStatus, 0, 0);

    return ntStatus;
}

//******************************************************************************
//
// I82930_StopDevice()
//
// This routine handles IRP_MJ_PNP, IRP_MN_STOP_DEVICE
//
// The PnP Manager sends this IRP at IRQL PASSIVE_LEVEL in the context of a
// system thread.
//
// The PnP Manager only sends this IRP if a prior IRP_MN_QUERY_STOP_DEVICE
// completed successfully.
//
// This IRP is handled first by the driver at the top of the device stack and
// then by each lower driver in the attachment chain.
//
// A driver must set Irp->IoStatus.Status to STATUS_SUCCESS.  A driver must
// not fail this IRP.  If a driver cannot release the device's hardware
// resources, it can fail a query-stop IRP, but once it succeeds the query-stop
// request it must succeed the stop request.
//
//******************************************************************************

NTSTATUS
I82930_StopDevice (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    PDEVICE_EXTENSION   deviceExtension;
    NTSTATUS            ntStatus;

    DBGPRINT(2, ("enter: I82930_StopDevice\n"));

    LOGENTRY('STOP', DeviceObject, Irp, 0);

    DBGFBRK(DBGF_BRK_STOPDEVICE);

    deviceExtension = DeviceObject->DeviceExtension;

    // Release the device resources allocated during IRP_MN_START_DEVICE
    //

    // Unconfigure the device
    //
    ntStatus = I82930_UnConfigure(DeviceObject);

    // Pass the IRP_MN_STOP_DEVICE Irp down the stack.
    //
    IoSkipCurrentIrpStackLocation(Irp);

    ntStatus = IoCallDriver(deviceExtension->StackDeviceObject,
                            Irp);

    DBGPRINT(2, ("exit:  I82930_StopDevice %08X\n", ntStatus));

    LOGENTRY('stop', ntStatus, 0, 0);

    return ntStatus;
}

//******************************************************************************
//
// I82930_RemoveDevice()
//
// This routine handles IRP_MJ_PNP, IRP_MN_REMOVE_DEVICE
//
// The PnP Manager sends this IRP at IRQL PASSIVE_LEVEL in the context of a
// system thread.
//
// This IRP is handled first by the driver at the top of the device stack and
// then by each lower driver in the attachment chain.
//
// A driver must set Irp->IoStatus.Status to STATUS_SUCCESS.  Drivers must not
// fail this IRP.
//
//******************************************************************************

NTSTATUS
I82930_RemoveDevice (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    PDEVICE_EXTENSION   deviceExtension;
    NTSTATUS            ntStatus;

    DBGPRINT(2, ("enter: I82930_RemoveDevice\n"));

    LOGENTRY('REMV', DeviceObject, Irp, 0);

    DBGFBRK(DBGF_BRK_REMOVEDEVICE);

    deviceExtension = DeviceObject->DeviceExtension;

    // Disable and free the SymbolicLink name if necessary
    //
    if (deviceExtension->SymbolicLinkName.Buffer != NULL)
    {
        ntStatus = IoSetDeviceInterfaceState(
                       &deviceExtension->SymbolicLinkName,
                       FALSE);

        RtlFreeUnicodeString(&deviceExtension->SymbolicLinkName);
    }

    // No more user requests at this point
    //
    deviceExtension->AcceptingRequests = FALSE;

    // Abort any requests that may be lingering on any of the endpoints.
    //
    if (deviceExtension->InterfaceInfo != NULL)
    {
        ULONG   pipeIndex;
        ULONG   numPipes;

        numPipes = deviceExtension->InterfaceInfo->NumberOfPipes;

        for (pipeIndex = 0; pipeIndex < numPipes; pipeIndex++)
        {
            I82930_AbortPipe(DeviceObject,
                             &deviceExtension->PipeList[pipeIndex]);
        }
    }

    // Decrement by one to match the initial one in AddDevice
    //
    DECREMENT_OPEN_COUNT(deviceExtension);

    LOGENTRY('rem1', DeviceObject, 0, 0);

    // Wait for all pending requests to complete
    //
    KeWaitForSingleObject(&deviceExtension->RemoveEvent,
                          Executive,
                          KernelMode,
                          FALSE,
                          NULL);

    LOGENTRY('rem2', DeviceObject, 0, 0);

    // Free everything that was allocated during IRP_MN_START_DEVICE
    //

    if (deviceExtension->DeviceDescriptor != NULL)
    {
        ExFreePool(deviceExtension->DeviceDescriptor);
    }

    if (deviceExtension->ConfigurationDescriptor != NULL)
    {
        ExFreePool(deviceExtension->ConfigurationDescriptor);
    }

    if (deviceExtension->InterfaceInfo != NULL)
    {
        ExFreePool(deviceExtension->InterfaceInfo);
    }

    // The documentation says to set the status before passing the Irp down
    //
    Irp->IoStatus.Status = STATUS_SUCCESS;

    // Pass the IRP_MN_REMOVE_DEVICE Irp down the stack.
    //
    IoSkipCurrentIrpStackLocation(Irp);

    ntStatus = IoCallDriver(deviceExtension->StackDeviceObject,
                            Irp);

    LOGENTRY('rem3', DeviceObject, 0, 0);

    // Free everything that was allocated during AddDevice
    //
    IoDetachDevice(deviceExtension->StackDeviceObject);

    IoDeleteDevice(DeviceObject);

    DBGPRINT(2, ("exit:  I82930_RemoveDevice %08X\n", ntStatus));

    LOGENTRY('remv', ntStatus, 0, 0);

    return ntStatus;
}

//******************************************************************************
//
// I82930_QueryStopRemoveDevice()
//
// This routine handles IRP_MJ_PNP, IRP_MN_QUERY_STOP_DEVICE and
// IRP_MN_QUERY_REMOVE_DEVICE.
//
// The PnP Manager sends this IRP at IRQL PASSIVE_LEVEL in the context of a
// system thread.
//
// This IRP is handled first by the driver at the top of the device stack and
// then by each lower driver in the attachment chain.
//
//******************************************************************************

NTSTATUS
I82930_QueryStopRemoveDevice (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    PDEVICE_EXTENSION   deviceExtension;
    NTSTATUS            ntStatus;

    DBGPRINT(2, ("enter: I82930_QueryStopRemoveDevice\n"));

    LOGENTRY('QSRD', DeviceObject, Irp, 0);

    DBGFBRK(DBGF_BRK_QUERYSTOPDEVICE);

    deviceExtension = DeviceObject->DeviceExtension;

    // Disable the SymbolicLink name
    //
    ntStatus = IoSetDeviceInterfaceState(
                   &deviceExtension->SymbolicLinkName,
                   FALSE);

    // No more user requests at this point
    //
    deviceExtension->AcceptingRequests = FALSE;

    // If there are no opens, OK to STOP or REMOVE
    //
    if (deviceExtension->OpenCount == 1)
    {
        LOGENTRY('qsr1', 0, 0, 0);

        // The documentation says to set the status before passing the Irp down
        //
        Irp->IoStatus.Status = STATUS_SUCCESS;

        // Pass the IRP_MN_QUERY_STOP/REMOVE_DEVICE Irp down the stack.
        //
        IoSkipCurrentIrpStackLocation(Irp);

        ntStatus = IoCallDriver(deviceExtension->StackDeviceObject,
                                Irp);

    }
    else
    {
        LOGENTRY('qsr2', deviceExtension->OpenCount, 0, 0);

        ntStatus = STATUS_DEVICE_BUSY;

        Irp->IoStatus.Status = ntStatus;

        IoCompleteRequest(Irp, IO_NO_INCREMENT);
    }

    DBGPRINT(2, ("exit:  I82930_QueryStopRemoveDevice %08X\n", ntStatus));

    LOGENTRY('qsrd', ntStatus, 0, 0);

    return ntStatus;
}

//******************************************************************************
//
// I82930_CancelStopRemoveDevice()
//
// This routine handles IRP_MJ_PNP, IRP_MN_CANCEL_STOP_DEVICE and
// IRP_MN_CANCEL_REMOVE_DEVICE.
//
// The PnP Manager sends this IRP at IRQL PASSIVE_LEVEL in the context of a
// system thread.
//
// This IRP must be handled first by the underlying bus driver for a device
// and then by each higher driver in the device stack.
//
//******************************************************************************

NTSTATUS
I82930_CancelStopRemoveDevice (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    PDEVICE_EXTENSION   deviceExtension;
    NTSTATUS            ntStatus;

    DBGPRINT(2, ("enter: I82930_CancelStopRemoveDevice\n"));

    LOGENTRY('CSRD', DeviceObject, Irp, 0);

    DBGFBRK(DBGF_BRK_CANCELSTOPDEVICE);

    deviceExtension = DeviceObject->DeviceExtension;

    // Pass the IRP_MN_CANCEL_STOP/REMOVE_DEVICE Irp down the stack first.
    //
    ntStatus = I82930_SyncPassDownIrp(DeviceObject,
                                      Irp,
                                      TRUE);
    if (!NT_SUCCESS(ntStatus))
    {
        DBGPRINT(1, ("Lower driver failed IRP_MN_CANCEL_STOP/REMOVE_DEVICE\n"));
        goto I82930_CancelStopRemoveDeviceDone;
    }

    // All set for user requests at this point
    //
    deviceExtension->AcceptingRequests = TRUE;

    // Enable the SymbolicLink name
    //
    ntStatus = IoSetDeviceInterfaceState(
                   &deviceExtension->SymbolicLinkName,
                   TRUE);

    if (!NT_SUCCESS(ntStatus))
    {
        DBGPRINT(1, ("IoSetDeviceInterfaceState failed\n"));
        Irp->IoStatus.Status = ntStatus;
        goto I82930_CancelStopRemoveDeviceDone;
    }

I82930_CancelStopRemoveDeviceDone:

    // Must complete request since completion routine returned
    // STATUS_MORE_PROCESSING_REQUIRED
    //
    IoCompleteRequest(Irp, IO_NO_INCREMENT);

    DBGPRINT(2, ("exit:  I82930_CancelStopRemoveDevice %08X\n", ntStatus));

    LOGENTRY('csrd', ntStatus, 0, 0);

    return ntStatus;
}

//******************************************************************************
//
// I82930_QueryCapabilities()
//
// This routine handles IRP_MJ_PNP, IRP_MN_QUERY_CAPABILITIES.
//
// The PnP Manager sends this IRP at IRQL PASSIVE_LEVEL in the context of a
// an arbitrary thread.
//
//******************************************************************************

NTSTATUS
I82930_QueryCapabilities (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp
    )
{
    PIO_STACK_LOCATION      irpStack;
    PDEVICE_CAPABILITIES    deviceCapabilities;
    NTSTATUS                ntStatus;

    PAGED_CODE();

    DBGPRINT(2, ("enter: I82930_QueryCapabilities\n"));

    LOGENTRY('FQCP', DeviceObject, Irp, 0);

    irpStack = IoGetCurrentIrpStackLocation(Irp);

    deviceCapabilities = irpStack->Parameters.DeviceCapabilities.Capabilities;

    // Pass IRP_MN_QUERY_CAPABILITIES Irp down the stack first before we do
    // anything.
    //
    ntStatus = I82930_SyncPassDownIrp(DeviceObject,
                                      Irp,
                                      TRUE);
    if (!NT_SUCCESS(ntStatus))
    {
        DBGPRINT(1, ("Lower driver failed IRP_MN_QUERY_CAPABILITIES\n"));
    }
    else
    {
        deviceCapabilities->SurpriseRemovalOK = TRUE;
    }

    IoCompleteRequest(Irp, IO_NO_INCREMENT);

    DBGPRINT(2, ("exit:  I82930_QueryCapabilities %08X\n", ntStatus));

    LOGENTRY('fqcp', ntStatus, 0, 0);

    return ntStatus;
}

//******************************************************************************
//
// I82930_SyncPassDownIrp()
//
//******************************************************************************

NTSTATUS
I82930_SyncPassDownIrp (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp,
    IN BOOLEAN          CopyToNext
    )
{
    PDEVICE_EXTENSION   deviceExtension;
    NTSTATUS            ntStatus;
    KEVENT              localevent;

    DBGPRINT(2, ("enter: I82930_SyncPassDownIrp\n"));

    deviceExtension = DeviceObject->DeviceExtension;

    // Initialize the event we'll wait on
    //
    KeInitializeEvent(&localevent,
                      SynchronizationEvent,
                      FALSE);

    if (CopyToNext)
    {
        // Next Stack Location not set up, copy Current Stack Location
        // to the Next Stack Location.
        //
        IoCopyCurrentIrpStackLocationToNext(Irp);
    }

    // Set the completion routine, which will signal the event
    //
    IoSetCompletionRoutine(Irp,
                           I82930_SyncCompletionRoutine,
                           &localevent,
                           TRUE,    // InvokeOnSuccess
                           TRUE,    // InvokeOnError
                           TRUE);   // InvokeOnCancel

    // Pass the Irp down the stack
    //
    ntStatus = IoCallDriver(deviceExtension->StackDeviceObject,
                            Irp);

    // If the request is pending, block until it completes
    //
    if (ntStatus == STATUS_PENDING)
    {
        KeWaitForSingleObject(&localevent,
                              Executive,
                              KernelMode,
                              FALSE,
                              NULL);

        ntStatus = Irp->IoStatus.Status;
    }

    DBGPRINT(2, ("exit:  I82930_SyncPassDownIrp %08X\n", ntStatus));

    return ntStatus;
}

//******************************************************************************
//
// I82930_SyncCompletionRoutine()
//
// Completion routine used by I82930_SyncPassDownIrp and
// I82930_SyncSendUsbRequest
//
// If the Irp is one we allocated ourself, DeviceObject is NULL unless we
// allocated a stack location for ourself and initialized the DeviceObject
// pointer in our stack location.
//
//******************************************************************************

NTSTATUS
I82930_SyncCompletionRoutine (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PIRP             Irp,
    IN PVOID            Context
    )
{
    PKEVENT kevent;

    LOGENTRY('SCR ', DeviceObject, Irp, Irp->IoStatus.Status);

    kevent = (PKEVENT)Context;

    KeSetEvent(kevent,
               IO_NO_INCREMENT,
               FALSE);

    return STATUS_MORE_PROCESSING_REQUIRED;
}

//******************************************************************************
//
// I82930_SyncSendUsbRequest()
//
// Must be called at IRQL <= DISPATCH_LEVEL
//
//******************************************************************************

NTSTATUS
I82930_SyncSendUsbRequest (
    IN PDEVICE_OBJECT   DeviceObject,
    IN PURB             Urb
    )
{
    PDEVICE_EXTENSION   deviceExtension;
    KEVENT              localevent;
    PIRP                irp;
    PIO_STACK_LOCATION  nextStack;
    NTSTATUS            ntStatus;

    DBGPRINT(3, ("enter: I82930_SyncSendUsbRequest\n"));

    deviceExtension = DeviceObject->DeviceExtension;

    // Initialize the event we'll wait on
    //
    KeInitializeEvent(&localevent,
                      SynchronizationEvent,
                      FALSE);

    // Allocate the Irp
    //
    irp = IoAllocateIrp(deviceExtension->StackDeviceObject->StackSize, FALSE);

    LOGENTRY('SSUR', DeviceObject, irp, Urb);

    if (irp == NULL)
    {
        return STATUS_INSUFFICIENT_RESOURCES;
    }

    // Set the Irp parameters
    //
    nextStack = IoGetNextIrpStackLocation(irp);

    nextStack->MajorFunction = IRP_MJ_INTERNAL_DEVICE_CONTROL;

    nextStack->Parameters.DeviceIoControl.IoControlCode =
        IOCTL_INTERNAL_USB_SUBMIT_URB;

    nextStack->Parameters.Others.Argument1 = Urb;

    // Set the completion routine, which will signal the event
    //
    IoSetCompletionRoutine(irp,
                           I82930_SyncCompletionRoutine,
                           &localevent,
                           TRUE,    // InvokeOnSuccess
                           TRUE,    // InvokeOnError
                           TRUE);   // InvokeOnCancel



    // Pass the Irp & Urb down the stack
    //
    ntStatus = IoCallDriver(deviceExtension->StackDeviceObject,
                            irp);

    // If the request is pending, block until it completes
    //
    if (ntStatus == STATUS_PENDING)
    {
        LARGE_INTEGER timeout;

        // Specify a timeout of 5 seconds to wait for this call to complete.
        //
        timeout.QuadPart = -10000 * 5000;

        ntStatus = KeWaitForSingleObject(&localevent,
                                         Executive,
                                         KernelMode,
                                         FALSE,
                                         &timeout);

        if (ntStatus == STATUS_TIMEOUT)
        {
            ntStatus = STATUS_IO_TIMEOUT;

            // Cancel the Irp we just sent.
            //
            IoCancelIrp(irp);

            // And wait until the cancel completes
            //
            KeWaitForSingleObject(&localevent,
                                  Executive,
                                  KernelMode,
                                  FALSE,
                                  NULL);
        }
        else
        {
            ntStatus = irp->IoStatus.Status;
        }
    }

    // Done with the Irp, now free it.
    //
    IoFreeIrp(irp);

    LOGENTRY('ssur', ntStatus, Urb, Urb->UrbHeader.Status);

    DBGPRINT(3, ("exit:  I82930_SyncSendUsbRequest %08X\n", ntStatus));

    return ntStatus;
}

//******************************************************************************
//
// I82930_GetDescriptor()
//
// Must be called at IRQL <= DISPATCH_LEVEL
//
//******************************************************************************

NTSTATUS
I82930_GetDescriptor (
    IN PDEVICE_OBJECT   DeviceObject,
    IN UCHAR            Recipient,
    IN UCHAR            DescriptorType,
    IN UCHAR            Index,
    IN USHORT           LanguageId,
    IN ULONG            RetryCount,
    IN ULONG            DescriptorLength,
    OUT PUCHAR         *Descriptor
    )
{
    USHORT      function;
    PURB        urb;
    NTSTATUS    ntStatus;

    DBGPRINT(2, ("enter: I82930_GetDescriptor\n"));

    // Set the URB function based on Recipient {Device, Interface, Endpoint}
    //
    switch (Recipient)
    {
        case USB_RECIPIENT_DEVICE:
            function = URB_FUNCTION_GET_DESCRIPTOR_FROM_DEVICE;
            break;
        case USB_RECIPIENT_INTERFACE:
            function = URB_FUNCTION_GET_DESCRIPTOR_FROM_INTERFACE;
            break;
        case USB_RECIPIENT_ENDPOINT:
            function = URB_FUNCTION_GET_DESCRIPTOR_FROM_ENDPOINT;
            break;
        default:
            *Descriptor = NULL;
            return STATUS_INVALID_PARAMETER;
    }

    // Allocate a descriptor buffer
    //
    *Descriptor = ExAllocatePoolWithTag(NonPagedPool,
                                        DescriptorLength,
                                        POOL_TAG);

    if (*Descriptor != NULL)
    {
        // Allocate a URB for the Get Descriptor request
        //
        urb = ExAllocatePoolWithTag(NonPagedPool,
                                    sizeof(struct _URB_CONTROL_DESCRIPTOR_REQUEST),
                                    POOL_TAG);

        if (urb != NULL)
        {
            do
            {
                // Initialize the URB
                //
                urb->UrbHeader.Function = function;
                urb->UrbHeader.Length = sizeof(struct _URB_CONTROL_DESCRIPTOR_REQUEST);
                urb->UrbControlDescriptorRequest.TransferBufferLength = DescriptorLength;
                urb->UrbControlDescriptorRequest.TransferBuffer = *Descriptor;
                urb->UrbControlDescriptorRequest.TransferBufferMDL = NULL;
                urb->UrbControlDescriptorRequest.UrbLink = NULL;
                urb->UrbControlDescriptorRequest.DescriptorType = DescriptorType;
                urb->UrbControlDescriptorRequest.Index = Index;
                urb->UrbControlDescriptorRequest.LanguageId = LanguageId;

                // Send the URB down the stack
                //
                ntStatus = I82930_SyncSendUsbRequest(DeviceObject,
                                                     urb);

                if (NT_SUCCESS(ntStatus))
                {
                    // No error, make sure the length and type are correct
                    //
                    if ((DescriptorLength ==
                         urb->UrbControlDescriptorRequest.TransferBufferLength) &&
                        (DescriptorType ==
                         ((PUSB_COMMON_DESCRIPTOR)*Descriptor)->bDescriptorType))
                    {
                        // The length and type are correct, all done
                        //
                        break;
                    }
                    else
                    {
                        // No error, but the length or type is incorrect
                        //
                        ntStatus = STATUS_DEVICE_DATA_ERROR;
                    }
                }

            } while (RetryCount-- > 0);

            ExFreePool(urb);
        }
        else
        {
            // Failed to allocate the URB
            //
            ExFreePool(*Descriptor);
            ntStatus = STATUS_INSUFFICIENT_RESOURCES;
        }
    }
    else
    {
        // Failed to allocate the descriptor buffer
        //
        ntStatus = STATUS_INSUFFICIENT_RESOURCES;
    }

    if (!NT_SUCCESS(ntStatus))
    {
        *Descriptor = NULL;
    }

    DBGPRINT(2, ("exit:  I82930_GetDescriptor %08X\n", ntStatus));

    return ntStatus;
}

//******************************************************************************
//
// I82930_SelectConfiguration()
//
// Must be called at IRQL <= DISPATCH_LEVEL
//
//******************************************************************************

NTSTATUS
I82930_SelectConfiguration (
    IN PDEVICE_OBJECT   DeviceObject
    )
{
    NTSTATUS    ntStatus;
    PURB        urb;
    ULONG       i;
    PDEVICE_EXTENSION               deviceExtension;
    PUSB_CONFIGURATION_DESCRIPTOR   configurationDescriptor;
    PUSBD_INTERFACE_LIST_ENTRY      interfaceList;
    PUSB_INTERFACE_DESCRIPTOR       interfaceDescriptor;
    PUSBD_INTERFACE_INFORMATION     interfaceInfo;

    DBGPRINT(2, ("enter: I82930_SelectConfiguration\n"));

    LOGENTRY('SCON', DeviceObject, 0, 0);

    deviceExtension = DeviceObject->DeviceExtension;
    configurationDescriptor = deviceExtension->ConfigurationDescriptor;


    // Allocate storage for an Inteface List to use as an input/output
    // parameter to USBD_CreateConfigurationRequestEx().
    //
    interfaceList = ExAllocatePool(
                        PagedPool,
                        sizeof(USBD_INTERFACE_LIST_ENTRY) * 2
                        );

    if (interfaceList)
    {
        // Parse the ConfigurationDescriptor (including all Interface and
        // Endpoint Descriptors) and locate a Interface Descriptor which
        // matches the InterfaceNumber, AlternateSetting, InterfaceClass,
        // InterfaceSubClass, and InterfaceProtocol parameters.  In our case
        // we just grab the first Interface Descriptor from the Configuration
        // Descriptor.
        //
        interfaceDescriptor = USBD_ParseConfigurationDescriptorEx(
                                  configurationDescriptor,
                                  configurationDescriptor,
                                  -1, // InterfaceNumber, don't care
                                  -1, // AlternateSetting, don't care
                                  -1, // InterfaceClass, don't care
                                  -1, // InterfaceSubClass, don't care
                                  -1  // InterfaceProtocol, don't care
                                  );

        if (interfaceDescriptor)
        {
            // Add the single Interface Descriptor we care about to the
            // interface list, then terminate the list.
            //
            interfaceList[0].InterfaceDescriptor = interfaceDescriptor;
            interfaceList[1].InterfaceDescriptor = NULL;

            // Create a SELECT_CONFIGURATION URB, turning the Interface
            // Descriptors in the interfaceList into USBD_INTERFACE_INFORMATION
            // structures in the URB.
            //
            urb = USBD_CreateConfigurationRequestEx(
                      configurationDescriptor,
                      interfaceList
                      );

            if (urb)
            {
                interfaceInfo = &urb->UrbSelectConfiguration.Interface;

                // Override the USBD_DEFAULT_MAXIMUM_TRANSFER_SIZE
                // for all pipes.
                //
                for (i = 0; i < interfaceInfo->NumberOfPipes; i++)
                {
                    interfaceInfo->Pipes[i].MaximumTransferSize = 0x10000;
                }

                // Now issue the USB request to set the Configuration
                //
                ntStatus = I82930_SyncSendUsbRequest(DeviceObject,
                                                     urb);

                if (NT_SUCCESS(ntStatus))
                {
                    // Save the configuration handle for this device in
                    // the Device Extension.
                    //
                    deviceExtension->ConfigurationHandle =
                        urb->UrbSelectConfiguration.ConfigurationHandle;

                    // Save a copy of the interface information returned
                    // by the SELECT_CONFIGURATION request in the Device
                    // Extension.  This gives us a list of PIPE_INFORMATION
                    // structures for each pipe opened in this configuration.
                    //
                    ASSERT(deviceExtension->InterfaceInfo == NULL);

                    deviceExtension->InterfaceInfo = ExAllocatePool(
                                                         PagedPool,
                                                         interfaceInfo->Length
                                                     );

                    if (deviceExtension->InterfaceInfo)
                    {
                        ULONG   pipeIndex;
                        ULONG   numPipes;

                        RtlCopyMemory(
                            deviceExtension->InterfaceInfo,
                            interfaceInfo,
                            interfaceInfo->Length
                            );

                        // Initialize the PipeList array pointers back into the
                        // InterfaceInfo.
                        //
                        numPipes = deviceExtension->InterfaceInfo->NumberOfPipes;

                        for (pipeIndex = 0; pipeIndex < numPipes; pipeIndex++)
                        {
                            deviceExtension->PipeList[pipeIndex].PipeIndex =
                                (UCHAR)pipeIndex;

                            deviceExtension->PipeList[pipeIndex].PipeInfo  =
                                &deviceExtension->InterfaceInfo->Pipes[pipeIndex];
                        }
                    }
                    else
                    {
                        // Could not allocate a copy of interface information
                        //
                        ntStatus = STATUS_INSUFFICIENT_RESOURCES;
                    }
                }

                // Done with the URB
                //
                ExFreePool(urb);
            }
            else
            {
                // Could not allocate urb
                //
                ntStatus = STATUS_INSUFFICIENT_RESOURCES;
            }
        }
        else
        {
            // Did not parse an Interface Descriptor out of the Configuration
            // Descriptor, the Configuration Descriptor must be bad.
            //
            ntStatus = STATUS_UNSUCCESSFUL;
        }

        // Done with the interface list
        //
        ExFreePool(interfaceList);
    }
    else
    {
        // Could not allocate Interface List
        //
        ntStatus = STATUS_INSUFFICIENT_RESOURCES;
    }

    DBGPRINT(2, ("exit:  I82930_SelectConfiguration %08X\n", ntStatus));

    LOGENTRY('scon', ntStatus, 0, 0);

    return ntStatus;
}

//******************************************************************************
//
// I82930_UnConfigure()
//
// Must be called at IRQL <= DISPATCH_LEVEL
//
//******************************************************************************

NTSTATUS
I82930_UnConfigure (
    IN PDEVICE_OBJECT   DeviceObject
    )
{
    PDEVICE_EXTENSION   deviceExtension;
    NTSTATUS            ntStatus;
    PURB                urb;
    ULONG               ulSize;

    DBGPRINT(2, ("enter: I82930_UnConfigure\n"));

    LOGENTRY('UCON', DeviceObject, 0, 0);

    deviceExtension = DeviceObject->DeviceExtension;

    // Allocate a URB for the SELECT_CONFIGURATION request.  As we are
    // unconfiguring the device, the request needs no pipe and interface
    // information structures.
    //
    ulSize = sizeof(struct _URB_SELECT_CONFIGURATION) -
             sizeof(USBD_INTERFACE_INFORMATION);

    urb = ExAllocatePool(
              NonPagedPool,
              ulSize
              );

    if (urb)
    {
        // Initialize the URB.  A NULL Configuration Descriptor indicates
        // that the device should be unconfigured.
        //
        UsbBuildSelectConfigurationRequest(
            urb,
            (USHORT)ulSize,
            NULL
            );

        // Now issue the USB request to set the Configuration
        //
        ntStatus = I82930_SyncSendUsbRequest(DeviceObject,
                                             urb);

        // Done with the URB now.
        //
        ExFreePool(urb);

        // The device is no longer configured.
        //
        deviceExtension->ConfigurationHandle = 0;

        if (deviceExtension->InterfaceInfo != NULL)
        {
            ExFreePool(deviceExtension->InterfaceInfo);

            deviceExtension->InterfaceInfo = NULL;
        }
    }
    else
    {
        // Could not allocate the URB.
        //
        ntStatus = STATUS_INSUFFICIENT_RESOURCES;
    }

    DBGPRINT(2, ("exit:  I82930_UnConfigure %08X\n", ntStatus));

    LOGENTRY('ucon', ntStatus, 0, 0);

    return ntStatus;
}

//******************************************************************************
//
// I82930_SelectAlternateInterface()
//
// Must be called at IRQL <= DISPATCH_LEVEL
//
//******************************************************************************

NTSTATUS
I82930_SelectAlternateInterface (
    IN PDEVICE_OBJECT   DeviceObject,
    IN UCHAR            AlternateSetting
    )
{
    NTSTATUS    ntStatus;
    USHORT      urbSize;
    PURB        urb;
    ULONG       i;
    PDEVICE_EXTENSION               deviceExtension;
    PUSB_CONFIGURATION_DESCRIPTOR   configurationDescriptor;
    PUSB_INTERFACE_DESCRIPTOR       interfaceDescriptor;
    PUSBD_INTERFACE_INFORMATION     interfaceInfo;

    DBGPRINT(2, ("enter: I82930_SelectAlternateInterface\n"));

    LOGENTRY('SALT', DeviceObject, 0, 0);

    deviceExtension = DeviceObject->DeviceExtension;
    configurationDescriptor = deviceExtension->ConfigurationDescriptor;

    interfaceDescriptor = USBD_ParseConfigurationDescriptorEx(
                              configurationDescriptor,
                              configurationDescriptor,
                              -1, // InterfaceNumber, don't care
                              AlternateSetting,
                              -1, // InterfaceClass, don't care
                              -1, // InterfaceSubClass, don't care
                              -1  // InterfaceProtocol, don't care
                              );

    if (interfaceDescriptor != NULL)
    {
        urbSize = GET_SELECT_INTERFACE_REQUEST_SIZE(interfaceDescriptor->bNumEndpoints);

        urb = ExAllocatePoolWithTag(NonPagedPool,
                                    urbSize,
                                    POOL_TAG);

        if (urb != NULL)
        {
            RtlZeroMemory(urb, urbSize);

            urb->UrbHeader.Length   = urbSize;

            urb->UrbHeader.Function = URB_FUNCTION_SELECT_INTERFACE;

            urb->UrbSelectInterface.ConfigurationHandle =
                deviceExtension->ConfigurationHandle;

            interfaceInfo = &urb->UrbSelectInterface.Interface;

            interfaceInfo->Length = GET_USBD_INTERFACE_SIZE(interfaceDescriptor->bNumEndpoints);

            interfaceInfo->InterfaceNumber = interfaceDescriptor->bInterfaceNumber;

            interfaceInfo->AlternateSetting = AlternateSetting;

            for (i = 0; i < interfaceDescriptor->bNumEndpoints; i++)
            {
                interfaceInfo->Pipes[i].MaximumTransferSize = 0x10000;
            }

            // Now issue the USB request to select the alternate interface
            //
            ntStatus = I82930_SyncSendUsbRequest(DeviceObject,
                                                 urb);

            if (NT_SUCCESS(ntStatus))
            {
                if (deviceExtension->InterfaceInfo != NULL)
                {
                    ExFreePool(deviceExtension->InterfaceInfo);

                    deviceExtension->InterfaceInfo = NULL;
                }

                // Save a copy of the interface information returned
                // by the SELECT_INTERFACE request in the Device
                // Extension.  This gives us a list of PIPE_INFORMATION
                // structures for each pipe opened in this configuration.
                //
                deviceExtension->InterfaceInfo = ExAllocatePool(
                                                     PagedPool,
                                                     interfaceInfo->Length
                                                     );

                if (deviceExtension->InterfaceInfo)
                {
                    ULONG   pipeIndex;
                    ULONG   numPipes;

                    RtlCopyMemory(deviceExtension->InterfaceInfo,
                                  interfaceInfo,
                                  interfaceInfo->Length
                                  );

                    // Initialize the PipeList array pointers back into the
                    // InterfaceInfo.
                    //
                    numPipes = deviceExtension->InterfaceInfo->NumberOfPipes;

                    for (pipeIndex = 0; pipeIndex < numPipes; pipeIndex++)
                    {
                        deviceExtension->PipeList[pipeIndex].PipeIndex =
                            (UCHAR)pipeIndex;

                        deviceExtension->PipeList[pipeIndex].PipeInfo  =
                            &deviceExtension->InterfaceInfo->Pipes[pipeIndex];
                    }
                }
                else
                {
                    // Could not allocate a copy of interface information
                    //
                    ntStatus = STATUS_INSUFFICIENT_RESOURCES;
                }
            }

            // Done with the URB
            //
            ExFreePool(urb);
        }
        else
        {
            // Could not allocate urb
            //
            ntStatus = STATUS_INSUFFICIENT_RESOURCES;
        }
    }
    else
    {
        // Bad AlternateSetting
        //
        ntStatus = STATUS_INVALID_PARAMETER;

    }

    DBGPRINT(2, ("exit:  I82930_SelectAlternateInterface %08X\n", ntStatus));

    LOGENTRY('salt', ntStatus, 0, 0);

    return ntStatus;
}