reactos操作系统实现(149)

IntVideoPortFindAdapter函数主要用来查找到相应显示卡，并且把显示卡驱动安装到对象管理器里，以便GUI界面调用时，可以找到相应驱动程序显示。具体实现代码如下：

#001 NTSTATUS NTAPI

#002 IntVideoPortFindAdapter(

#003 IN PDRIVER_OBJECT DriverObject,

#004 IN PVIDEO_PORT_DRIVER_EXTENSION DriverExtension,

#005 IN PDEVICE_OBJECT DeviceObject)

#006 {

#007 WCHAR DeviceVideoBuffer[20];

#008 PVIDEO_PORT_DEVICE_EXTENSION DeviceExtension;

#009 ULONG Size;

#010 NTSTATUS Status;

#011 VIDEO_PORT_CONFIG_INFO ConfigInfo;

#012 SYSTEM_BASIC_INFORMATION SystemBasicInfo;

#013 UCHAR Again = FALSE;

#014 WCHAR DeviceBuffer[20];

#015 UNICODE_STRING DeviceName;

#016 WCHAR SymlinkBuffer[20];

#017 UNICODE_STRING SymlinkName;

#018 BOOL LegacyDetection = FALSE;

#019 ULONG DeviceNumber;

#020

获取驱动程序扩展。

#021 DeviceExtension = (PVIDEO_PORT_DEVICE_EXTENSION)DeviceObject->DeviceExtension;

获取显示卡的设备号。

#022 DeviceNumber = DeviceExtension->DeviceNumber;

#023

#024 /*

#025 * Setup a ConfigInfo structure that we will pass to HwFindAdapter.

#026 */

#027

设置配置信息结构，传送给查找显示卡函数。

#028 RtlZeroMemory(&ConfigInfo,sizeof(VIDEO_PORT_CONFIG_INFO));

#029 ConfigInfo.Length = sizeof(VIDEO_PORT_CONFIG_INFO);

#030 ConfigInfo.AdapterInterfaceType = DeviceExtension->AdapterInterfaceType;

#031 if (ConfigInfo.AdapterInterfaceType == PCIBus)

#032 ConfigInfo.InterruptMode = LevelSensitive;

#033 else

#034 ConfigInfo.InterruptMode = Latched;

驱动程序注册表路径。

#035 ConfigInfo.DriverRegistryPath = DriverExtension->RegistryPath.Buffer;

#036 ConfigInfo.VideoPortGetProcAddress = IntVideoPortGetProcAddress;

#037 ConfigInfo.SystemIoBusNumber = DeviceExtension->SystemIoBusNumber;

#038 ConfigInfo.BusInterruptLevel = DeviceExtension->InterruptLevel;

#039 ConfigInfo.BusInterruptVector = DeviceExtension->InterruptVector;

#040

查询系统的基本信息。

#041 Size = sizeof(SystemBasicInfo);

#042 Status = ZwQuerySystemInformation(

#043 SystemBasicInformation,

#044 &SystemBasicInfo,

#045 Size,

#046 &Size);

#047

#048 if (NT_SUCCESS(Status))

#049 {

#050 ConfigInfo.SystemMemorySize =

#051 SystemBasicInfo.NumberOfPhysicalPages *

#052 SystemBasicInfo.PageSize;

#053 }

#054

#055 /*

#056 * Call miniport HwVidFindAdapter entry point to detect if

#057 * particular device is present. There are two possible code

#058 * paths. The first one is for Legacy drivers (NT4) and cases

#059 * when we don't have information about what bus we're on. The

#060 * second case is the standard one for Plug & Play drivers.

#061 */

如果物理设备对象为空，说明是旧的驱动程序。

#062 if (DeviceExtension->PhysicalDeviceObject == NULL)

#063 {

#064 LegacyDetection = TRUE;

#065 }

#066

#067 if (LegacyDetection)

#068 {

#069 ULONG BusNumber,MaxBuses;

#070

分析总线上所有设备。

#071 MaxBuses = DeviceExtension->AdapterInterfaceType == PCIBus ? 8 : 1;

#072

#073 for (BusNumber = 0; BusNumber < MaxBuses; BusNumber++)

#074 {

#075 DeviceExtension->SystemIoBusNumber =

#076 ConfigInfo.SystemIoBusNumber = BusNumber;

#077

#078 RtlZeroMemory(&DeviceExtension->MiniPortDeviceExtension,

#079 DriverExtension->InitializationData.HwDeviceExtensionSize);

#080

#081 /* FIXME: Need to figure out what string to pass as param 3. */

查找设备是否存在。

#082 Status = DriverExtension->InitializationData.HwFindAdapter(

#083 &DeviceExtension->MiniPortDeviceExtension,

#084 DriverExtension->HwContext,

#085 NULL,

#086 &ConfigInfo,

#087 &Again);

#088

#089 if (Status == ERROR_DEV_NOT_EXIST)

#090 {

#091 continue;

#092 }

#093 else if (Status == NO_ERROR)

#094 {

#095 break;

#096 }

#097 else

#098 {

#099 WARN_(VIDEOPRT,"HwFindAdapter call failed with error 0x%X/n",Status);

#100 RtlFreeUnicodeString(&DeviceExtension->RegistryPath);

#101 IoDeleteDevice(DeviceObject);

#102

#103 return Status;

#104 }

#105 }

#106 }

#107 else

#108 {

#109 /* FIXME: Need to figure out what string to pass as param 3. */

#110 Status = DriverExtension->InitializationData.HwFindAdapter(

#111 &DeviceExtension->MiniPortDeviceExtension,

#112 DriverExtension->HwContext,

#113 NULL,

#114 &ConfigInfo,

#115 &Again);

#116 }

#117

#118 if (Status != NO_ERROR)

#119 {

#120 WARN_(VIDEOPRT,Status);

#121 RtlFreeUnicodeString(&DeviceExtension->RegistryPath);

#122 IoDeleteDevice(DeviceObject);

#123 return Status;

#124 }

#125

到这里已经发现设备已经存在，下面开始创建符号连接，并关联到设备对象里，还设置了显示卡的中断和定时器。

#126 /*

#127 * Now we know the device is present,so let's do all additional tasks

#128 * such as creating symlinks or setting up interrupts and timer.

#129 */

#130

创建UNICODE的设备名称。

#131 /* Create a unicode device name. */

#132 swprintf(DeviceBuffer,L"//Device//Video%lu",DeviceNumber);

#133 RtlInitUnicodeString(&DeviceName,DeviceBuffer);

#134

创建显示设备的符号连接。

#135 /* Create symbolic link "/??/DISPLAYx" */

#136 swprintf(SymlinkBuffer,L"//??//DISPLAY%lu",DeviceNumber + 1);

#137 RtlInitUnicodeString(&SymlinkName,SymlinkBuffer);

#138 IoCreateSymbolicLink(&SymlinkName,&DeviceName);

#139

添加显示设备到注册表。

#140 /* Add entry to DEVICEMAP/VIDEO key in registry. */

#141 swprintf(DeviceVideoBuffer,L"//Device//Video%d",DeviceNumber);

#142 RtlWriteRegistryValue(

#143 RTL_REGISTRY_DEVICEMAP,

#144 L"VIDEO",

#145 DeviceVideoBuffer,

#146 REG_SZ,

#147 DeviceExtension->RegistryPath.Buffer,

#148 DeviceExtension->RegistryPath.MaximumLength);

#149

#150 RtlWriteRegistryValue(

#151 RTL_REGISTRY_DEVICEMAP,

#152 L"VIDEO",

#153 L"MaxObjectNumber",

#154 REG_DWORD,

#155 &DeviceNumber,

#156 sizeof(DeviceNumber));

#157

#158 /* FIXME: Allocate hardware resources for device. */

#159

#160 /*

#161 * Allocate interrupt for device.

#162 */

#163

分配中断号给显示设备。

#164 if (!IntVideoPortSetupInterrupt(DeviceObject,DriverExtension,&ConfigInfo))

#165 {

#166 RtlFreeUnicodeString(&DeviceExtension->RegistryPath);

#167 IoDeleteDevice(DeviceObject);

#168 return STATUS_INSUFFICIENT_RESOURCES;

#169 }

#170

#171 /*

#172 * Allocate timer for device.

#173 */

#174

分配定时器给显示设备。

#175 if (!IntVideoPortSetupTimer(DeviceObject,DriverExtension))

#176 {

#177 if (DeviceExtension->InterruptObject != NULL)

#178 IoDisconnectInterrupt(DeviceExtension->InterruptObject);

#179 RtlFreeUnicodeString(&DeviceExtension->RegistryPath);

#180 IoDeleteDevice(DeviceObject);

#181 WARN_(VIDEOPRT,"STATUS_INSUFFICIENT_RESOURCES/n");

#182 return STATUS_INSUFFICIENT_RESOURCES;

#183 }

#184

查询显示设备的子设备。

#185 /*

#186 * Query children of the device.

#187 */

#188 VideoPortEnumerateChildren(&DeviceExtension->MiniPortDeviceExtension,NULL);

#189

#190 INFO_(VIDEOPRT,"STATUS_SUCCESS/n");

#191 return STATUS_SUCCESS;

#192}

（编辑：李大同）

【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容!