deviceio.cpp

一个通用的usb驱动程序列程

#include "WdmUsb.h"
#pragma code_seg("PAGE")
NTSTATUS StartDevice(IN PWDMUSB_DEVICE_EXTENSION dx,
				     IN PCM_RESOURCE_LIST AllocatedResourcesTranslated)
{
	NTSTATUS  status;
	KdPrint(("StartDevice"));
	if(dx->GotResources)
		return STATUS_SUCCESS;
	//--------------------------USB---------------------------------
	UsbResetDevice(dx);
    PUSB_DEVICE_DESCRIPTOR DeviceDescriptor;
    ULONG size;
	status=UsbGetDeviceDescriptor(dx,DeviceDescriptor,size);
    if(NT_SUCCESS(status))
	{
		if(dx->DeviceDescriptor)ExFreePool(dx->DeviceDescriptor);
		dx->DeviceDescriptor=DeviceDescriptor;
		KdPrint(("DeviceDescriptor size:%x",size));
	}
	status=UsbSelectConfiguration(dx);    
	if(!NT_SUCCESS(status))
	{
		ExFreePool(dx->DeviceDescriptor);
        KdPrint(("StartDevice UsbSelectConfiguration fail"));
		dx->GotResources=false;
    }
	else
	{
		dx->GotResources=true;
		UsbBuildPipeList(dx);
		KdPrint(("StartDevice UsbSelectConfiguration success"));
	}
	//--------------------------------------------------------------
	return STATUS_SUCCESS;
}
VOID StopDevice(IN PWDMUSB_DEVICE_EXTENSION dx)
{
	KdPrint(("StopDevice"));
	if(!dx->GotResources)
		return;
//	UsbCancelAllPendingIrp(dx);
	UsbDeselectConfiguration(dx);
	dx->GotResources=false;
}
void SetPowerState(IN PWDMUSB_DEVICE_EXTENSION dx, 
				   IN DEVICE_POWER_STATE NewDevicePowerState)
{
	KdPrint(("SetPowerState %d", NewDevicePowerState));	
	dx->PowerState=NewDevicePowerState;
	POWER_STATE NewState;
    NewState.DeviceState=NewDevicePowerState;
	if(KeGetCurrentIrql()==DISPATCH_LEVEL&&NewDevicePowerState!=PowerDeviceD0)
	{
		KdPrint(("SetPowerState IRQL %d fail", KeGetCurrentIrql()));
	}
	else
		PoSetPowerState(dx->fdo,DevicePowerState,NewState);
}
#pragma code_seg()