detect.c

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/*
 * COPYRIGHT:       See COPYING in the top level directory
 * PROJECT:         ReactOS Serial enumerator driver
 * FILE:            drivers/bus/serenum/detect.c
 * PURPOSE:         Detection of serial devices
 *
 * PROGRAMMERS:     Jason Filby (jasonfilby@yahoo.com)
 *                  Filip Navara (xnavara@volny.cz)
 *                  Hervé Poussineau (hpoussin@reactos.org)
 */
 
#include "serenum.h"
 
#include <debug.h>
 
static NTSTATUS
DeviceIoControl(
    IN PDEVICE_OBJECT DeviceObject,
    IN ULONG CtlCode,
    IN PVOID InputBuffer OPTIONAL,
    IN ULONG_PTR InputBufferSize,
    IN OUT PVOID OutputBuffer OPTIONAL,
    IN OUT PULONG_PTR OutputBufferSize)
{
    KEVENT Event;
    PIRP Irp;
    IO_STATUS_BLOCK IoStatus;
    NTSTATUS Status;
 
    KeInitializeEvent (&Event, NotificationEvent, FALSE);
 
    Irp = IoBuildDeviceIoControlRequest(CtlCode,
        DeviceObject,
        InputBuffer,
        InputBufferSize,
        OutputBuffer,
        (OutputBufferSize) ? *OutputBufferSize : 0,
        FALSE,
        &Event,
        &IoStatus);
    if (Irp == NULL)
    {
        WARN_(SERENUM, "IoBuildDeviceIoControlRequest() failed\n");
        return STATUS_INSUFFICIENT_RESOURCES;
    }
 
    Status = IoCallDriver(DeviceObject, Irp);
 
    if (Status == STATUS_PENDING)
    {
        INFO_(SERENUM, "Operation pending\n");
        KeWaitForSingleObject(&Event, Suspended, KernelMode, FALSE, NULL);
        Status = IoStatus.Status;
    }
 
    if (OutputBufferSize)
    {
        *OutputBufferSize = IoStatus.Information;
    }
 
    return Status;
}
 
static NTSTATUS
ReadBytes(
    IN PDEVICE_OBJECT LowerDevice,
    OUT PUCHAR Buffer,
    IN ULONG BufferSize,
    OUT PULONG_PTR FilledBytes)
{
    PIRP Irp;
    IO_STATUS_BLOCK ioStatus;
    KEVENT event;
    LARGE_INTEGER zero;
    NTSTATUS Status;
 
    KeInitializeEvent(&event, NotificationEvent, FALSE);
    zero.QuadPart = 0;
    Irp = IoBuildSynchronousFsdRequest(
        IRP_MJ_READ,
        LowerDevice,
        Buffer, BufferSize,
        &zero,
        &event,
        &ioStatus);
    if (!Irp)
        return FALSE;
 
    Status = IoCallDriver(LowerDevice, Irp);
    if (Status == STATUS_PENDING)
    {
        KeWaitForSingleObject(&event, Suspended, KernelMode, FALSE, NULL);
        Status = ioStatus.Status;
    }
    INFO_(SERENUM, "Bytes received: %lu/%lu\n",
        ioStatus.Information, BufferSize);
    *FilledBytes = ioStatus.Information;
    return Status;
}
 
static NTSTATUS
ReportDetectedDevice(
    IN PDEVICE_OBJECT DeviceObject,
    IN PUNICODE_STRING DeviceDescription,
    IN PUNICODE_STRING DeviceId,
    IN PUNICODE_STRING InstanceId,
    IN PUNICODE_STRING HardwareIds,
    IN PUNICODE_STRING CompatibleIds)
{
    PDEVICE_OBJECT Pdo = NULL;
    PPDO_DEVICE_EXTENSION PdoDeviceExtension = NULL;
    PFDO_DEVICE_EXTENSION FdoDeviceExtension;
    NTSTATUS Status;
 
    TRACE_(SERENUM, "ReportDetectedDevice() called with %wZ (%wZ) detected\n", DeviceId, DeviceDescription);
 
    Status = IoCreateDevice(
        DeviceObject->DriverObject,
        sizeof(PDO_DEVICE_EXTENSION),
        NULL,
        FILE_DEVICE_CONTROLLER,
        FILE_AUTOGENERATED_DEVICE_NAME,
        FALSE,
        &Pdo);
    if (!NT_SUCCESS(Status)) goto ByeBye;
 
    Pdo->Flags |= DO_BUS_ENUMERATED_DEVICE;
    Pdo->Flags |= DO_POWER_PAGABLE;
    PdoDeviceExtension = (PPDO_DEVICE_EXTENSION)Pdo->DeviceExtension;
    FdoDeviceExtension = (PFDO_DEVICE_EXTENSION)DeviceObject->DeviceExtension;
    RtlZeroMemory(PdoDeviceExtension, sizeof(PDO_DEVICE_EXTENSION));
    PdoDeviceExtension->Common.IsFDO = FALSE;
    Status = DuplicateUnicodeString(RTL_DUPLICATE_UNICODE_STRING_NULL_TERMINATE, DeviceDescription, &PdoDeviceExtension->DeviceDescription);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DuplicateUnicodeString(RTL_DUPLICATE_UNICODE_STRING_NULL_TERMINATE, DeviceId, &PdoDeviceExtension->DeviceId);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DuplicateUnicodeString(RTL_DUPLICATE_UNICODE_STRING_NULL_TERMINATE, InstanceId, &PdoDeviceExtension->InstanceId);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DuplicateUnicodeString(RTL_DUPLICATE_UNICODE_STRING_NULL_TERMINATE, HardwareIds, &PdoDeviceExtension->HardwareIds);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DuplicateUnicodeString(RTL_DUPLICATE_UNICODE_STRING_NULL_TERMINATE, CompatibleIds, &PdoDeviceExtension->CompatibleIds);
    if (!NT_SUCCESS(Status)) goto ByeBye;
 
    /* Device attached to serial port (Pdo) may delegate work to
     * serial port stack (Fdo = DeviceObject variable) */
    Pdo->StackSize = DeviceObject->StackSize + 1;
 
    FdoDeviceExtension->AttachedPdo = Pdo;
    PdoDeviceExtension->AttachedFdo = DeviceObject;
 
    Pdo->Flags |= DO_BUFFERED_IO;
    Pdo->Flags &= ~DO_DEVICE_INITIALIZING;
 
    return STATUS_SUCCESS;
 
ByeBye:
    if (Pdo)
    {
        ASSERT(PdoDeviceExtension);
        if (PdoDeviceExtension->DeviceDescription.Buffer)
            RtlFreeUnicodeString(&PdoDeviceExtension->DeviceDescription);
        if (PdoDeviceExtension->DeviceId.Buffer)
            RtlFreeUnicodeString(&PdoDeviceExtension->DeviceId);
        if (PdoDeviceExtension->InstanceId.Buffer)
            RtlFreeUnicodeString(&PdoDeviceExtension->InstanceId);
        if (PdoDeviceExtension->HardwareIds.Buffer)
            RtlFreeUnicodeString(&PdoDeviceExtension->HardwareIds);
        if (PdoDeviceExtension->CompatibleIds.Buffer)
            RtlFreeUnicodeString(&PdoDeviceExtension->CompatibleIds);
        IoDeleteDevice(Pdo);
    }
    return Status;
}
 
static BOOLEAN
IsValidPnpIdString(
    IN PUCHAR Buffer,
    IN ULONG BufferLength)
{
    ANSI_STRING String;
 
    /* FIXME: IsValidPnpIdString not implemented */
    UNIMPLEMENTED;
    String.Length = String.MaximumLength = BufferLength;
    String.Buffer = (PCHAR)Buffer;
    ERR_(SERENUM, "Buffer %Z\n", &String);
    return TRUE;
}
 
static NTSTATUS
ReportDetectedPnpDevice(
    IN PUCHAR Buffer,
    IN ULONG BufferLength)
{
    ANSI_STRING String;
 
    /* FIXME: ReportDetectedPnpDevice not implemented */
    UNIMPLEMENTED;
    String.Length = String.MaximumLength = BufferLength;
    String.Buffer = (PCHAR)Buffer;
    ERR_(SERENUM, "Buffer %Z\n", &String);
    /* Call ReportDetectedDevice */
    return STATUS_SUCCESS;
}
 
#define BEGIN_ID '('
#define END_ID ')'
 
static NTSTATUS
Wait(
    IN ULONG milliseconds)
{
    KTIMER Timer;
    LARGE_INTEGER DueTime;
 
    DueTime.QuadPart = milliseconds * -10;
    KeInitializeTimer(&Timer);
    KeSetTimer(&Timer, DueTime, NULL);
    return KeWaitForSingleObject(&Timer, Executive, KernelMode, FALSE, NULL);
}
 
NTSTATUS
SerenumDetectPnpDevice(
    IN PDEVICE_OBJECT DeviceObject,
    IN PDEVICE_OBJECT LowerDevice)
{
    HANDLE Handle = NULL;
    UCHAR Buffer[256];
    ULONG BaudRate;
    ULONG_PTR TotalBytesReceived = 0;
    ULONG_PTR Size;
    ULONG Msr, Purge;
    ULONG i;
    BOOLEAN BufferContainsBeginId = FALSE;
    BOOLEAN BufferContainsEndId = FALSE;
    SERIAL_LINE_CONTROL Lcr;
    SERIAL_TIMEOUTS Timeouts;
    SERIALPERF_STATS PerfStats;
    NTSTATUS Status;
 
    /* Open port */
    Status = ObOpenObjectByPointer(
        LowerDevice,
        OBJ_KERNEL_HANDLE,
        NULL,
        0,
        NULL,
        KernelMode,
        &Handle);
    if (!NT_SUCCESS(Status)) goto ByeBye;
 
    /* 1. COM port initialization, check for device enumerate */
    TRACE_(SERENUM, "COM port initialization, check for device enumerate\n");
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_CLR_DTR,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_CLR_RTS,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Wait(200);
    Size = sizeof(Msr);
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_GET_MODEMSTATUS,
        NULL, 0, &Msr, &Size);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    if ((Msr & SERIAL_DSR_STATE) == 0) goto DisconnectIdle;
 
    /* 2. COM port setup, 1st phase */
    TRACE_(SERENUM, "COM port setup, 1st phase\n");
    BaudRate = 1200;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_BAUD_RATE,
        &BaudRate, sizeof(BaudRate), NULL, 0);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Lcr.WordLength = 7;
    Lcr.Parity = NO_PARITY;
    Lcr.StopBits = STOP_BIT_1;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_LINE_CONTROL,
        &Lcr, sizeof(Lcr), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_CLR_DTR,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_CLR_RTS,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Wait(200);
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_DTR,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Wait(200);
 
    /* 3. Wait for response, 1st phase */
    TRACE_(SERENUM, "Wait for response, 1st phase\n");
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_RTS,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Timeouts.ReadIntervalTimeout = 0;
    Timeouts.ReadTotalTimeoutMultiplier = 0;
    Timeouts.ReadTotalTimeoutConstant = 200;
    Timeouts.WriteTotalTimeoutMultiplier = Timeouts.WriteTotalTimeoutConstant = 0;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_TIMEOUTS,
        &Timeouts, sizeof(Timeouts), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = ReadBytes(LowerDevice, Buffer, sizeof(Buffer), &Size);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    if (Size != 0) goto CollectPnpComDeviceId;
 
    /* 4. COM port setup, 2nd phase */
    TRACE_(SERENUM, "COM port setup, 2nd phase\n");
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_CLR_DTR,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_CLR_RTS,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Purge = SERIAL_PURGE_RXABORT | SERIAL_PURGE_RXCLEAR;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_PURGE,
        &Purge, sizeof(ULONG), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Wait(200);
 
    /* 5. Wait for response, 2nd phase */
    TRACE_(SERENUM, "Wait for response, 2nd phase\n");
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_DTR,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_RTS,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = ReadBytes(LowerDevice, Buffer, 1, &TotalBytesReceived);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    if (TotalBytesReceived != 0) goto CollectPnpComDeviceId;
    Size = sizeof(Msr);
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_GET_MODEMSTATUS,
        NULL, 0, &Msr, &Size);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    if ((Msr & SERIAL_DSR_STATE) == 0) goto VerifyDisconnect; else goto ConnectIdle;
 
    /* 6. Collect PnP COM device ID */
CollectPnpComDeviceId:
    TRACE_(SERENUM, "Collect PnP COM device ID\n");
    Timeouts.ReadIntervalTimeout = 200;
    Timeouts.ReadTotalTimeoutMultiplier = 0;
    Timeouts.ReadTotalTimeoutConstant = 2200;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_TIMEOUTS,
        &Timeouts, sizeof(Timeouts), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = ReadBytes(LowerDevice, &Buffer[TotalBytesReceived], sizeof(Buffer) - TotalBytesReceived, &Size);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    TotalBytesReceived += Size;
    Size = sizeof(PerfStats);
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_GET_STATS,
        NULL, 0, &PerfStats, &Size);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    if (PerfStats.FrameErrorCount + PerfStats.ParityErrorCount != 0) goto ConnectIdle;
    for (i = 0; i < TotalBytesReceived; i++)
    {
        if (Buffer[i] == BEGIN_ID) BufferContainsBeginId = TRUE;
        if (Buffer[i] == END_ID) BufferContainsEndId = TRUE;
    }
    if (TotalBytesReceived == 1 || BufferContainsEndId)
    {
        if (IsValidPnpIdString(Buffer, TotalBytesReceived))
        {
            Status = ReportDetectedPnpDevice(Buffer, TotalBytesReceived);
            goto ByeBye;
        }
        goto ConnectIdle;
    }
    if (!BufferContainsBeginId) goto ConnectIdle;
    if (!BufferContainsEndId) goto ConnectIdle;
    Size = sizeof(Msr);
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_GET_MODEMSTATUS,
        NULL, 0, &Msr, &Size);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    if ((Msr & SERIAL_DSR_STATE) == 0) goto VerifyDisconnect;
 
    /* 7. Verify disconnect */
VerifyDisconnect:
    TRACE_(SERENUM, "Verify disconnect\n");
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_DTR,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_CLR_RTS,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Wait(5000);
    goto DisconnectIdle;
 
    /* 8. Connect idle */
ConnectIdle:
    TRACE_(SERENUM, "Connect idle\n");
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_DTR,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_CLR_RTS,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    BaudRate = 300;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_BAUD_RATE,
        &BaudRate, sizeof(BaudRate), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Lcr.WordLength = 7;
    Lcr.Parity = NO_PARITY;
    Lcr.StopBits = STOP_BIT_1;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_LINE_CONTROL,
        &Lcr, sizeof(Lcr), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    if (TotalBytesReceived == 0)
        Status = STATUS_DEVICE_NOT_CONNECTED;
    else
        Status = STATUS_SUCCESS;
    goto ByeBye;
 
    /* 9. Disconnect idle */
DisconnectIdle:
    TRACE_(SERENUM, "Disconnect idle\n");
    /* FIXME: report to OS device removal, if it was present */
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_DTR,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_CLR_RTS,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    BaudRate = 300;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_BAUD_RATE,
        &BaudRate, sizeof(BaudRate), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Lcr.WordLength = 7;
    Lcr.Parity = NO_PARITY;
    Lcr.StopBits = STOP_BIT_1;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_LINE_CONTROL,
        &Lcr, sizeof(Lcr), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = STATUS_DEVICE_NOT_CONNECTED;
 
ByeBye:
    /* Close port */
    if (Handle)
        ZwClose(Handle);
    return Status;
}
 
NTSTATUS
SerenumDetectLegacyDevice(
    IN PDEVICE_OBJECT DeviceObject,
    IN PDEVICE_OBJECT LowerDevice)
{
    HANDLE Handle = NULL;
    ULONG Fcr, Mcr;
    ULONG BaudRate;
    ULONG Command;
    SERIAL_TIMEOUTS Timeouts;
    SERIAL_LINE_CONTROL LCR;
    ULONG i, Count = 0;
    UCHAR Buffer[16];
    UNICODE_STRING DeviceDescription;
    UNICODE_STRING DeviceId;
    UNICODE_STRING InstanceId;
    UNICODE_STRING HardwareIds;
    UNICODE_STRING CompatibleIds;
    NTSTATUS Status;
 
    TRACE_(SERENUM, "SerenumDetectLegacyDevice(DeviceObject %p, LowerDevice %p)\n",
        DeviceObject,
        LowerDevice);
 
    RtlZeroMemory(Buffer, sizeof(Buffer));
 
    /* Open port */
    Status = ObOpenObjectByPointer(
        LowerDevice,
        OBJ_KERNEL_HANDLE,
        NULL,
        0,
        NULL,
        KernelMode,
        &Handle);
    if (!NT_SUCCESS(Status)) return Status;
 
    /* Reset UART */
    TRACE_(SERENUM, "Reset UART\n");
    Mcr = 0; /* MCR: DTR/RTS/OUT2 off */
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_MODEM_CONTROL,
        &Mcr, sizeof(Mcr), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
 
    /* Set communications parameters */
    TRACE_(SERENUM, "Set communications parameters\n");
    /* DLAB off */
    Fcr = 0;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_FIFO_CONTROL,
        &Fcr, sizeof(Fcr), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    /* Set serial port speed */
    BaudRate = 1200;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_BAUD_RATE,
        &BaudRate, sizeof(BaudRate), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    /* Set LCR */
    LCR.WordLength = 7;
    LCR.Parity = NO_PARITY;
    LCR.StopBits = STOP_BITS_2;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_LINE_CONTROL,
        &LCR, sizeof(LCR), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
 
    /* Flush receive buffer */
    TRACE_(SERENUM, "Flush receive buffer\n");
    Command = SERIAL_PURGE_RXCLEAR;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_MODEM_CONTROL,
        &Command, sizeof(Command), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    /* Wait 100 ms */
    Wait(100);
 
    /* Enable DTR/RTS */
    TRACE_(SERENUM, "Enable DTR/RTS\n");
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_DTR,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_RTS,
        NULL, 0, NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
 
    /* Set timeout to 500 microseconds */
    TRACE_(SERENUM, "Set timeout to 500 microseconds\n");
    Timeouts.ReadIntervalTimeout = 100;
    Timeouts.ReadTotalTimeoutMultiplier = 0;
    Timeouts.ReadTotalTimeoutConstant = 500;
    Timeouts.WriteTotalTimeoutMultiplier = Timeouts.WriteTotalTimeoutConstant = 0;
    Status = DeviceIoControl(LowerDevice, IOCTL_SERIAL_SET_TIMEOUTS,
        &Timeouts, sizeof(Timeouts), NULL, NULL);
    if (!NT_SUCCESS(Status)) goto ByeBye;
 
    /* Fill the read buffer */
    TRACE_(SERENUM, "Fill the read buffer\n");
    Status = ReadBytes(LowerDevice, Buffer, sizeof(Buffer)/sizeof(Buffer[0]), (PVOID)&Count);
    if (!NT_SUCCESS(Status)) goto ByeBye;
 
    RtlInitUnicodeString(&DeviceId, L"Serenum\\Mouse");
    RtlInitUnicodeString(&InstanceId, L"0000"); /* FIXME */
    for (i = 0; i < Count; i++)
    {
        if (Buffer[i] == 'B')
        {
            /* Sign for Microsoft Ballpoint */
            /* Hardware id: *PNP0F09
             * Compatible id: *PNP0F0F, SERIAL_MOUSE
             */
            RtlInitUnicodeString(&DeviceDescription, L"Microsoft Ballpoint device");
            SerenumInitMultiSzString(&HardwareIds, "*PNP0F09", NULL);
            SerenumInitMultiSzString(&CompatibleIds, "*PNP0F0F", "SERIAL_MOUSE", NULL);
            Status = ReportDetectedDevice(DeviceObject,
                &DeviceDescription, &DeviceId, &InstanceId, &HardwareIds, &CompatibleIds);
            RtlFreeUnicodeString(&HardwareIds);
            RtlFreeUnicodeString(&CompatibleIds);
            goto ByeBye;
        }
        else if (Buffer[i] == 'M')
        {
            /* Sign for Microsoft Mouse protocol followed by button specifier */
            if (i == sizeof(Buffer) - 1)
            {
                /* Overflow Error */
                Status = STATUS_DEVICE_NOT_CONNECTED;
                goto ByeBye;
            }
            switch (Buffer[i + 1])
            {
                case '3':
                    /* Hardware id: *PNP0F08
                     * Compatible id: SERIAL_MOUSE
                     */
                    RtlInitUnicodeString(&DeviceDescription, L"Microsoft Mouse with 3-buttons");
                    SerenumInitMultiSzString(&HardwareIds, "*PNP0F08", NULL);
                    SerenumInitMultiSzString(&CompatibleIds, "SERIAL_MOUSE", NULL);
                    break;
                default:
                    /* Hardware id: *PNP0F01
                     * Compatible id: SERIAL_MOUSE
                     */
                    RtlInitUnicodeString(&DeviceDescription, L"Microsoft Mouse with 2-buttons or Microsoft Wheel Mouse");
                    SerenumInitMultiSzString(&HardwareIds, "*PNP0F01", NULL);
                    SerenumInitMultiSzString(&CompatibleIds, "SERIAL_MOUSE", NULL);
                    break;
            }
            Status = ReportDetectedDevice(DeviceObject,
                &DeviceDescription, &DeviceId, &InstanceId, &HardwareIds, &CompatibleIds);
            RtlFreeUnicodeString(&HardwareIds);
            RtlFreeUnicodeString(&CompatibleIds);
            goto ByeBye;
        }
    }
 
    Status = STATUS_DEVICE_NOT_CONNECTED;
 
ByeBye:
    /* Close port */
    if (Handle)
        ZwClose(Handle);
    return Status;
}