// ===================================================================
//
//
//      test98.c
//
//      rev 1.0 beta
//
//      USB device driver for USB Device Example as depicted in
//      the book "Developing USB PC Peripherals" 
//
//      kernel mode driver 
//
//      author  : Wooi Ming Tan 
//      date    : 31 May 98
//
//      test98.c  - main module containing DriverEntry routine 
//      testpnp.c - handles USB PnP and power IRPs
//      testusb.c - handles some USB IRPs         
//
//      developed under  
//      - Windows 98 Beta 3 DDK environment 
//      - users can create and copy to \98DDK\src\usb\test98\sys directory
//     
//      NOTE:
//      The driver (testdrv.sys) generated by the codes (test98.c, testpnp.c and 
//      testusb.c) has been tested under a few Windows 98 Beta 3 systems.   
//      The driver has been made compatible with the applications software and 
//      device firmware supplied with the book "Developing USB PC Peripherals".
//      For more information on the code examples, please also refer to 
//      Chapter 8 "USB Application Software, WDM Driver, and Firmware Examples" 
//      of the book.
//
//      The author would also like to thank Kenneth Ray for his
//      advice on revising the code.
//
//
// ==============================================================================

#include <wdm.h>
#include <initguid.h>

#include "test98.h"
#include "stdio.h"
#include "testdrv.h"

NTSTATUS DriverEntry (PDRIVER_OBJECT, PUNICODE_STRING);

NTSTATUS
DriverEntry (
    IN  PDRIVER_OBJECT  DriverObject,
    IN  PUNICODE_STRING UniRegistryPath
    )
/*
    Entry point for the loading of the drivr.   

*/
{
    PDEVICE_OBJECT  device;

    UNREFERENCED_PARAMETER (UniRegistryPath);

    DriverObject->MajorFunction [IRP_MJ_CREATE] =
    DriverObject->MajorFunction [IRP_MJ_CLOSE]  = Test_Create;  
    
    // routines to handle system PnP and power management reqeusts 
    DriverObject->MajorFunction [IRP_MJ_PNP]    = Test98_PnP;
    DriverObject->MajorFunction [IRP_MJ_POWER]  = Test98_Power;
    
    // handles user mode DeviceIoControl() calls
    DriverObject->MajorFunction [IRP_MJ_DEVICE_CONTROL] = Test_ProcessIOCTL;
    
    DriverObject->DriverUnload = Test98_DriverUnload;
    
    // called when device plug-in to reat Funtional Device Object (FDO) 
    DriverObject->DriverExtension->AddDevice = Test98_AddDevice;
    
    DriverObject->MajorFunction[IRP_MJ_WRITE] = Test_Write;
    DriverObject->MajorFunction[IRP_MJ_READ] = Test_Read;

    return STATUS_SUCCESS;
}

// =======================================================================
VOID
Test98_DriverUnload (
    IN PDRIVER_OBJECT Driver
    )
/*
        to clean up the stuff we did in driver entry.

*/
{
    UNREFERENCED_PARAMETER (Driver);
    PAGED_CODE();

    ASSERT (NULL == Driver->DeviceObject);

    //
    // Here we free any resources allocated in DriverEntry
    //

    return;
}

// =======================================================================
VOID
Test98_DecIoCount (
    PFDO_DEVICE_DATA Data
    )
{
    if (0 == InterlockedDecrement (&Data->OutstandingIO)) {
        KeSetEvent (&Data->RemoveEvent, 0, FALSE);
    }
}

// =======================================================================
NTSTATUS
Test98_IncIoCount (
    PFDO_DEVICE_DATA Data
    )
{
    InterlockedIncrement (&Data->OutstandingIO);
    if (Data->Removed) {

        if (0 == InterlockedDecrement (&Data->OutstandingIO)) {
            KeSetEvent (&Data->RemoveEvent, 0, FALSE);
        }
        return STATUS_DELETE_PENDING;
    }
    return STATUS_SUCCESS;
}