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Windows CE usb驱动程序

上述讲了堆理论,可能读者脑袋都已经大了,为此,我们举个简单的例子来详细说明一下驱动程序的开发过程。

例如我们有个USB Mouse设备,设备信息描述如下:
Device Descriptor:
bcdUSB: 0x0100
bDeviceClass: 0x00
bDeviceSubClass: 0x00
bDeviceProtocol: 0x00
bMaxPacketSize0: 0x08 (8)
idVendor: 0x05E3 (Genesys Logic Inc.)
idProduct: 0x0001
bcdDevice: 0x0101
iManufacturer: 0x00
iProduct: 0x01
iSerialNumber: 0x00
bNumConfigurations: 0x01

ConnectionStatus: DeviceConnected
Current Config value: 0x01
Device Bus Speed: Low
Device Address: 0x02
Open Pipes: 1

Endpoint Descriptor:
bEndpointAddress: 0x81
Transfer Type: Interrupt
wMaxPacketSize: 0x0003 (3)
bInterval: 0x0A

可以看出上述设备有一个中断PIPE,包的最大值为3。可能有人问上述的值怎么得到的,win2k 的DDK中有个usbview的例程,编译一下,将你的USB设备插到PC机的USB口中,运行usbview.exe即可看得相应的设备信息。

有了这些基本信息,就可以编写USB设备了,首先声明一下,下面的代码取自微软的USB鼠标样本程序,版权归微软所有,此处仅仅借用来描述一下USB鼠标驱动的开发过程,读者如需要引用此代码,需要得到微软的同意。

首先,必须输出USBD要求调用的三个函数,首先到设备插入到USB端口时,USBD会调用USBDeviceAttach()函数,相应的代码如下:
extern "C" BOOL
USBDeviceAttach(
USB_HANDLE hDevice, // USB设备句柄
LPCUSB_FUNCS lpUsbFuncs, // USBDI的函数集合
LPCUSB_INTERFACE lpInterface, // 设备接口描述信息
LPCWSTR szUniqueDriverId, // 设备ID描述字符串。
LPBOOL fAcceptControl, // 返回TRUE,标识我们可以控制此设备, 反之表示不能控制
DWORD dwUnused)
{
*fAcceptControl = FALSE;
// 我们的鼠标设备有特定的描述信息,要检测是否是我们的设备。
if (lpInterface == NULL)
return FALSE;
// 打印相关的USB设备接口描述信息。
DEBUGMSG(ZONE_INIT,(TEXT("USBMouse: DeviceAttach, IF %u, #EP:%u, Class:%u, Sub:%u,Prot:%u\r\n"), lpInterface->Descriptor.bInterfaceNumber,lpInterface->Descriptor.bNumEndpoints, lpInterface->Descriptor.bInterfaceClass,lpInterface->Descriptor.bInterfaceSubClass,lpInterface->Descriptor.bInterfaceProtocol));
// 初试数据USB鼠标类,产生一个接受USB鼠标数据的线程
CMouse * pMouse = new CMouse(hDevice, lpUsbFuncs, lpInterface);
if (pMouse == NULL)
return FALSE;

if (!pMouse->Initialize())
{
delete pMouse;
return FALSE;
}

// 注册一个监控USB设备事件的回调函数,用于监控USB设备是否已经拔掉。
(*lpUsbFuncs->lpRegisterNotificationRoutine)(hDevice,
USBDeviceNotifications, pMouse);

*fAcceptControl = TRUE;
return TRUE;
}

第二个函数是 USBInstallDriver()函数,
一些基本定义如下:
const WCHAR gcszRegisterClientDriverId[] = L"RegisterClientDriverID";
const WCHAR gcszRegisterClientSettings[] = L"RegisterClientSettings";
const WCHAR gcszUnRegisterClientDriverId[] = L"UnRegisterClientDriverID";
const WCHAR gcszUnRegisterClientSettings[] = L"UnRegisterClientSettings";
const WCHAR gcszMouseDriverId[] = L"Generic_Sample_Mouse_Driver";

函数接口如下:
extern "C" BOOL
USBInstallDriver(
LPCWSTR szDriverLibFile) // @parm [IN] - Contains client driver DLL name
{
BOOL fRet = FALSE;
HINSTANCE hInst = LoadLibrary(L"USBD.DLL");

// 注册USB设备信息
if(hInst)
{
LPREGISTER_CLIENT_DRIVER_ID pRegisterId = (LPREGISTER_CLIENT_DRIVER_ID)
GetProcAddress(hInst, gcszRegisterClientDriverId);

LPREGISTER_CLIENT_SETTINGS pRegisterSettings =
(LPREGISTER_CLIENT_SETTINGS) GetProcAddress(hInst,
gcszRegisterClientSettings);

if(pRegisterId && pRegisterSettings)
{
USB_DRIVER_SETTINGS DriverSettings;

DriverSettings.dwCount = sizeof(DriverSettings);

// 设置我们的特定的信息。
DriverSettings.dwVendorId = USB_NO_INFO;
DriverSettings.dwProductId = USB_NO_INFO;
DriverSettings.dwReleaseNumber = USB_NO_INFO;

DriverSettings.dwDeviceClass = USB_NO_INFO;
DriverSettings.dwDeviceSubClass = USB_NO_INFO;
DriverSettings.dwDeviceProtocol = USB_NO_INFO;

DriverSettings.dwInterfaceClass = 0x03; // HID
DriverSettings.dwInterfaceSubClass = 0x01; // boot device
DriverSettings.dwInterfaceProtocol = 0x02; // mouse

fRet = (*pRegisterId)(gcszMouseDriverId);

if(fRet)
{
fRet = (*pRegisterSettings)(szDriverLibFile,
gcszMouseDriverId, NULL, &DriverSettings);

if(!fRet)
{
//BUGBUG unregister the Client Driver’s ID
}
}
}
else
{
RETAILMSG(1,(TEXT("!USBMouse: Error getting USBD function pointers\r\n")));
}
FreeLibrary(hInst);
}
return fRet;
}
上述代码主要用于产生USB设备驱动程序需要的注册表信息,需要注意的是:USB设备驱动程序不使用标准的注册表函数,而是使用RegisterClientDriverID()和RegisterClientSettings来注册相应的设备信息。

另外一个函数是USBUninstallDriver()函数,具体代码如下:
extern "C" BOOL
USBUnInstallDriver()
{
BOOL fRet = FALSE;
HINSTANCE hInst = LoadLibrary(L"USBD.DLL");

if(hInst)
{
LPUN_REGISTER_CLIENT_DRIVER_ID pUnRegisterId =
(LPUN_REGISTER_CLIENT_DRIVER_ID)
GetProcAddress(hInst, gcszUnRegisterClientDriverId);

LPUN_REGISTER_CLIENT_SETTINGS pUnRegisterSettings =
(LPUN_REGISTER_CLIENT_SETTINGS) GetProcAddress(hInst,
gcszUnRegisterClientSettings);

if(pUnRegisterSettings)
{
USB_DRIVER_SETTINGS DriverSettings;

DriverSettings.dwCount = sizeof(DriverSettings);
// 必须填入与注册时相同的信息。
DriverSettings.dwVendorId = USB_NO_INFO;
DriverSettings.dwProductId = USB_NO_INFO;
DriverSettings.dwReleaseNumber = USB_NO_INFO;

DriverSettings.dwDeviceClass = USB_NO_INFO;
DriverSettings.dwDeviceSubClass = USB_NO_INFO;
DriverSettings.dwDeviceProtocol = USB_NO_INFO;

DriverSettings.dwInterfaceClass = 0x03; // HID
DriverSettings.dwInterfaceSubClass = 0x01; // boot device
DriverSettings.dwInterfaceProtocol = 0x02; // mouse

fRet = (*pUnRegisterSettings)(gcszMouseDriverId, NULL,
&DriverSettings);
}

if(pUnRegisterId)
{
BOOL fRetTemp = (*pUnRegisterId)(gcszMouseDriverId);
fRet = fRet ? fRetTemp : fRet;
}
FreeLibrary(hInst);
}
return fRet;
}
此函数主要用于删除USBInstallDriver()时创建的注册表信息,同样的它使用自己的函数接口UnRegisterClientDriverID()和UnRegisterClientSettings()来做相应的处理。

另外一个需要处理的注册的监控通知函数USBDeviceNotifications():
extern "C" BOOL USBDeviceNotifications(LPVOID lpvNotifyParameter, DWORD dwCode,
LPDWORD * dwInfo1, LPDWORD * dwInfo2, LPDWORD * dwInfo3,
LPDWORD * dwInfo4)
{
CMouse * pMouse = (CMouse *)lpvNotifyParameter;

switch(dwCode)
{
case USB_CLOSE_DEVICE:
//删除相关的资源。
delete pMouse;
return TRUE;
}
return FALSE;
}


USB鼠标的类的定义如下:
class CMouse
{
public:
CMouse::CMouse(USB_HANDLE hDevice, LPCUSB_FUNCS lpUsbFuncs,
LPCUSB_INTERFACE lpInterface);
~CMouse();

BOOL Initialize();
private:
// 传输完毕调用的回调函数
static DWORD CALLBACK MouseTransferCompleteStub(LPVOID lpvNotifyParameter);
// 中断处理函数
static ULONG CALLBACK CMouse::MouseThreadStub(PVOID context);
DWORD MouseTransferComplete();
DWORD MouseThread();

BOOL SubmitInterrupt();
BOOL HandleInterrupt();

BOOL m_fClosing;
BOOL m_fReadyForMouseEvents;

HANDLE m_hEvent;
HANDLE m_hThread;

USB_HANDLE m_hDevice;
USB_PIPE m_hInterruptPipe;
USB_TRANSFER m_hInterruptTransfer;

LPCUSB_FUNCS m_lpUsbFuncs;
LPCUSB_INTERFACE m_pInterface;

BOOL m_fPrevButton1;
BOOL m_fPrevButton2;
BOOL m_fPrevButton3;

// 数据接受缓冲区。
BYTE m_pbDataBuffer[8];
};

具体实现如下:

// 构造函数,初始化时调用
CMouse::CMouse(USB_HANDLE hDevice, LPCUSB_FUNCS lpUsbFuncs,
LPCUSB_INTERFACE lpInterface)
{
m_fClosing = FALSE;
m_fReadyForMouseEvents = FALSE;
m_hEvent = NULL;
m_hThread = NULL;

m_hDevice = hDevice;
m_hInterruptPipe = NULL;
m_hInterruptTransfer = NULL;

m_lpUsbFuncs = lpUsbFuncs;
m_pInterface = lpInterface;

m_fPrevButton1 = FALSE;
m_fPrevButton2 = FALSE;
m_fPrevButton3 = FALSE;

memset(m_pbDataBuffer, 0, sizeof(m_pbDataBuffer));
}

// 析构函数,用于清除申请的资源。
CMouse::~CMouse()
{
// 通知系统去关闭相关的函数接口。
m_fClosing = TRUE;

// Wake up the connection thread again and give it time to die.
if (m_hEvent != NULL)
{
// 通知关闭数据接受线程。
SetEvent(m_hEvent);

if (m_hThread != NULL)
{
DWORD dwWaitReturn;

dwWaitReturn = WaitForSingleObject(m_hThread, 1000);
if (dwWaitReturn != WAIT_OBJECT_0)
{
TerminateThread(m_hThread, DWORD(-1));
}
CloseHandle(m_hThread);
m_hThread = NULL;
}
CloseHandle(m_hEvent);
m_hEvent = NULL;
}

if(m_hInterruptTransfer)
(*m_lpUsbFuncs->lpCloseTransfer)(m_hInterruptTransfer);

if(m_hInterruptPipe)
(*m_lpUsbFuncs->lpClosePipe)(m_hInterruptPipe);
}


// 初始化USB鼠标驱动程序
BOOL CMouse::Initialize()
{
LPCUSB_DEVICE lpDeviceInfo = (*m_lpUsbFuncs->lpGetDeviceInfo)(m_hDevice);

// 检测配置:USB鼠标应该只有一个中断管道
if ((m_pInterface->lpEndpoints[0].Descriptor.bmAttributes & USB_ENDPOINT_TYPE_MASK) != USB_ENDPOINT_TYPE_INTERRUPT)
{
RETAILMSG(1,(TEXT("!USBMouse: EP 0 wrong type (%u)!\r\n"),
m_pInterface->lpEndpoints[0].Descriptor.bmAttributes));
return FALSE;
}
DEBUGMSG(ZONE_INIT,(TEXT("USBMouse: EP 0:MaxPacket: %u, Interval: %u\r\n"),
m_pInterface->lpEndpoints[0].Descriptor.wMaxPacketSize,
m_pInterface->lpEndpoints[0].Descriptor.bInterval));

m_hInterruptPipe = (*m_lpUsbFuncs->lpOpenPipe)(m_hDevice,
&m_pInterface->lpEndpoints[0].Descriptor);

if (m_hInterruptPipe == NULL) {
RETAILMSG(1,(TEXT("Mouse: Error opening interrupt pipe\r\n")));
return (FALSE);
}
m_hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
if (m_hEvent == NULL)
{
RETAILMSG(1,(TEXT("USBMouse: Error on CreateEvent for connect event\r\n")));
return(FALSE);
}
// 创建数据接受线程
m_hThread = CreateThread(0, 0, MouseThreadStub, this, 0, NULL);
if (m_hThread == NULL)
{
RETAILMSG(1,(TEXT("USBMouse: Error on CreateThread\r\n")));
return(FALSE);
}

return(TRUE);
}

// 从USB鼠标设备中读出数据,产生相应的鼠标事件。
BOOL CMouse::SubmitInterrupt()
{
if(m_hInterruptTransfer)
(*m_lpUsbFuncs->lpCloseTransfer)(m_hInterruptTransfer);

// 从USB鼠标PIPE中读数据
m_hInterruptTransfer = (*m_lpUsbFuncs->lpIssueInterruptTransfer)
(m_hInterruptPipe, MouseTransferCompleteStub, this,
USB_IN_TRANSFER | USB_SHORT_TRANSFER_OK, // 表示读数据
min(m_pInterface->lpEndpoints[0].Descriptor.wMaxPacketSize,
sizeof(m_pbDataBuffer)),
m_pbDataBuffer,
NULL);

if (m_hInterruptTransfer == NULL)
{
DEBUGMSG(ZONE_ERROR,(L "!USBMouse: Error in IssueInterruptTransfer\r\n"));
return FALSE;
}
else
{
DEBUGMSG(ZONE_TRANSFER,(L"USBMouse::SubmitInterrupt,Transfer:0x%X\r\n",
m_hInterruptTransfer));
}
return TRUE;
}

// 处理鼠标中断传输的数据
BOOL CMouse::HandleInterrupt()
{
DWORD dwError;
DWORD dwBytes;

DWORD dwFlags = 0;
INT dx = (signed char)m_pbDataBuffer[1];
INT dy = (signed char)m_pbDataBuffer[2];

BOOL fButton1 = m_pbDataBuffer[0] & 0x01 ? TRUE : FALSE;
BOOL fButton2 = m_pbDataBuffer[0] & 0x02 ? TRUE : FALSE;
BOOL fButton3 = m_pbDataBuffer[0] & 0x04 ? TRUE : FALSE;

if (!(*m_lpUsbFuncs->lpGetTransferStatus)(m_hInterruptTransfer, &dwBytes,&dwError))
{
DEBUGMSG(ZONE_ERROR,(TEXT("!USBMouse: Error in GetTransferStatus(0x%X)\r\n"),
m_hInterruptTransfer));
return FALSE;
}
else
{
DEBUGMSG(ZONE_TRANSFER,(TEXT("USBMouse::HandleInterrupt, hTransfer 0x%X complete (%u bytes, Error:%X)\r\n"),
m_hInterruptTransfer,dwBytes,dwError));
}

if (!SubmitInterrupt())
return FALSE;

if(dwError != USB_NO_ERROR)
{
DEBUGMSG(ZONE_ERROR,(TEXT("!USBMouse: Error 0x%X in interrupt transfer\r\n"),dwError));
return TRUE;
}

if(dwBytes < 3)
{
DEBUGMSG(ZONE_ERROR,(TEXT("!USBMouse: Invalid byte cnt %u from interrupt transfer\r\n"),dwBytes));
return TRUE;
}

if(dx || dy)
dwFlags |= MOUSEEVENTF_MOVE;

if(fButton1 != m_fPrevButton1)
{
if(fButton1)
dwFlags |= MOUSEEVENTF_LEFTDOWN;
else
dwFlags |= MOUSEEVENTF_LEFTUP;
}

if(fButton2 != m_fPrevButton2)
{
if(fButton2)
dwFlags |= MOUSEEVENTF_RIGHTDOWN;
else
dwFlags |= MOUSEEVENTF_RIGHTUP;
}

if(fButton3 != m_fPrevButton3)
{
if(fButton3)
dwFlags |= MOUSEEVENTF_MIDDLEDOWN;
else
dwFlags |= MOUSEEVENTF_MIDDLEUP;
}

m_fPrevButton1 = fButton1;
m_fPrevButton2 = fButton2;
m_fPrevButton3 = fButton3;

DEBUGMSG(ZONE_EVENTS,
(TEXT("USBMouse event: dx:%d, dy:%d, dwFlags:0x%X (B1:%u, B2:%u, B3:%u)\r\n"),
dx,dy,dwFlags,fButton1,fButton2,fButton3));

// 通知系统产生鼠标事件
if (m_fReadyForMouseEvents)
mouse_event(dwFlags, dx, dy, 0, 0);
else
m_fReadyForMouseEvents = IsAPIReady(SH_WMGR);

return TRUE;
}


DWORD CALLBACK CMouse::MouseTransferCompleteStub(LPVOID lpvNotifyParameter)
{
CMouse * pMouse = (CMouse *)lpvNotifyParameter;
return(pMouse->MouseTransferComplete());
}

// 数据传输完毕回调函数
DWORD CMouse::MouseTransferComplete()
{
if (m_hEvent)
SetEvent(m_hEvent);
return 0;
}


ULONG CALLBACK CMouse::MouseThreadStub(PVOID context)
{
CMouse * pMouse = (CMouse *)context;
return(pMouse->MouseThread());
}

// USB鼠标线程
DWORD CMouse::MouseThread()
{
DEBUGMSG(ZONE_INIT,(TEXT("USBMouse: Worker thread started\r\n")));
SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_HIGHEST);

if (SubmitInterrupt())
{
while (!m_fClosing)
{
WaitForSingleObject(m_hEvent, INFINITE);

if (m_fClosing)
break;

if ((*m_lpUsbFuncs->lpIsTransferComplete)(m_hInterruptTransfer))
{
if (!HandleInterrupt())
break;
}
else
{
RETAILMSG(1,(TEXT("!USBMouse: Event signalled, but transfer not complete\r\n")));
// The only time this should happen is if we get an error on the transfer
ASSERT(m_fClosing || (m_hInterruptTransfer == NULL));
break;
}
}
}
RETAILMSG(1,(TEXT("USBMouse: Worker thread exiting\r\n")));
return(0);
}

看 到了没有,其实USB的驱动程序编写就这么简单,类似的其他设备,例如打印机设备,就有Bulk OUT PIPE,需要Bulk传输,那就需要了解一下IssueBulkTransfer()的应用。当然如果是开发USB Mass Storage Disk的驱动,那就需要了解更多的协议,例如Bulk-Only Transport协议等。

微软的Windows CE.NET的Platform Build中已经带有USB Printer和USB Mass Storage Disk的驱动的源代码了,好好研究一下,你一定回受益非浅的。



参考资料:
1. 微软出版社 <<Windows Ce Device Driver Kit>>
2. <<Universal Serial Bus Specification 1.1>> 来自http:://www.usb.org

posted on 2008-12-03 10:35 井泉 阅读(1150) 评论(0)  编辑 收藏 引用


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