基于WINCE6.0系统，SD卡和flash作为PC机的U盘
基于WINCE6.0系统，SD卡和flash作为PC机的U盘
********************************LoongEmbedded********************************
作者：LoongEmbedded(kandi)
时间：2012.05.04
类别：WINCE驱动开发
********************************LoongEmbedded********************************
根据客户的要求，希望我们WINCE设备可以作为PC机器的可移动磁盘，并且可以通过应用软件能够实现mass storage和ActiveSync的切换，那怎么实现这个功能呢：
1. 系统组件
选择ActiveSync、mass storage和serial组件，如下图所示：
图1
2. 驱动的支持以及需要注意的注册表项
我们先来看USB客户端驱动的注册表信息
IF BSP_USBFNCLASS == MASS_STORAGE
[HKEY_LOCAL_MACHINE\Drivers\USB\FunctionDrivers]
"DefaultClientDriver"=- ; erase previous default
"DefaultClientDriver"="Mass_Storage_Class"
ENDIF BSP_USBFNCLASS
[HKEY_LOCAL_MACHINE\Drivers\USB\FunctionDrivers\Mass_Storage_Class]
"Dll"="usbmsfn.dll"
"InterfaceSubClass"=dword:06
"InterfaceProtocol"=dword:50
"DeviceName"="DSK1:" ; 被映射为U盘的存储设备的设备名
"FriendlyName"="Mass Storage";显示设备名
"idVendor"=dword:045E; Vendor ID，应该向USB组织申请
"Manufacturer"="Generic Manufacturer (PROTOTYPE--Remember to change idVendor)";厂商命
"idProduct"=dword:FFFF; Product ID，由厂商定义
"Product"="Generic Mass Storage (PROTOTYPE--Remember to change idVendor)";产品名
"bcdDevice"=dword:0;设备的版本号
[HKEY_LOCAL_MACHINE\Drivers\USB\FunctionDrivers\RNDIS]
"idVendor"=dword:0547
"Manufacturer"=LOC_USBFN_RNDIS_MANUFACTURER
"idProduct"=dword:2c2d
"Product"=LOC_USBFN_RNDIS_PRODUCT
[HKEY_LOCAL_MACHINE\Drivers\USB\FunctionDrivers\Serial_Class]
"FriendlyName"=LOC_USBFN_SERIAL_NAME
"idVendor"=dword:045E
"Manufacturer"=LOC_USBFN_SERIAL_MANUFACTURER
"idProduct"=dword:00CE
"Product"=LOC_USBFN_SERIAL_PRODUCT
"Index"=dword:5
[HKEY_CURRENT_USER\ControlPanel\Comm]
"Cnct"="`USB"
在上面的注册表信息中，如果要把SD卡或是flash分区作为PC机的可移动盘，一定要让"DeviceName"="DSK1:"中的1和SD卡驱动或是flash驱动的index一致，这样就可以实现这个功能了。
3. mass storage和ActiveSync切换
这个功能可以通过一个应用软件来实现，主要的工作如下：
⑴基于GUID调用FindFirstDevice函数获取到USB控制器驱动(比如s3c2450_usbfn.dll)的句柄。
⑵通过上面获取的驱动句柄，以控制码IOCTL_UFN_GET_CURRENT_CLIENT调用DeviceIoControl函数来获取当前已经加载的USB客户端驱动，然后以控制码IOCTL_UFN_CHANGE_CURRENT_CLIENT调用DeviceIoControl函数来切换USB客户端驱动(比如由mass storage切换为ActiveSync)。
⑶修改注册表信息，比如把"DefaultClientDriver"="Mass_Storage_Class"改为"DefaultClientDriver"="serial"
具体的代码如下：
#define FILE_DEVICE_UNKNOWN 0x00000022
#define METHOD_BUFFERED 0
#define FILE_ANY_ACCESS 0
#define CTL_CODE( DeviceType, Function, Method, Access ) ( \
((DeviceType) << 16) | ((Access) << 14) | ((Function) << 2) | (Method) \
)
#define _UFN_ACCESS_CTL_CODE(_Function) \
CTL_CODE(FILE_DEVICE_UNKNOWN, _Function, METHOD_BUFFERED, FILE_ANY_ACCESS)
#define IOCTL_UFN_GET_CURRENT_CLIENT _UFN_ACCESS_CTL_CODE(3)
#define IOCTL_UFN_CHANGE_CURRENT_CLIENT _UFN_ACCESS_CTL_CODE(4)
#define UFN_CLIENT_NAME_MAX_CHARS 128
#define UFN_CLIENT_DESCRIPTION_MAX_CHARS 250
typedef struct _UFN_CLIENT_INFO {
TCHAR szName[UFN_CLIENT_NAME_MAX_CHARS];
TCHAR szDescription[UFN_CLIENT_DESCRIPTION_MAX_CHARS];
} UFN_CLIENT_INFO, *PUFN_CLIENT_INFO;
typedef struct _UFN_CLIENT_NAME {
TCHAR szName[UFN_CLIENT_NAME_MAX_CHARS];
} UFN_CLIENT_NAME, *PUFN_CLIENT_NAME;
static HKEY hOpenKey=NULL;
#define DRIVER_USB_KEY TEXT("Drivers\\USB\\FunctionDrivers")
#define DRIVER_USB_NAME TEXT("DefaultClientDriver")
#define DRIVER_USB_VALUE_SERIAL TEXT("Serial_Class")
#define DRIVER_USB_VALUE_STORAGE TEXT("Mass_Storage_Class")
HANDLE GetUfncontroller()
{
HANDLE hUfn = NULL;
DEVMGR_DEVICE_INFORMATION di;
memset(&di, 0, sizeof(di));
di.dwSize = sizeof(di);
GUID guidUsbFn = { 0xE2BDC372, 0x598F, 0x4619, 0xBC, 0x50, 0x54, 0xB3, 0xF7, 0x84, 0x8D, 0x35 };
HANDLE hf = FindFirstDevice(DeviceSearchByGuid, &guidUsbFn, &di);
if (hf != INVALID_HANDLE_VALUE)
{
hUfn = CreateFile(di.szBusName, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, NULL);
CloseHandle(hf);
}
else
{
hUfn = INVALID_HANDLE_VALUE;
}
return hUfn;
}
void CusbfunctionswitchDlg::OnBnClickedStorageActivesyncSwitch()
{
// TODO: Add your control notification handler code here
HANDLE hDisk = NULL;
BOOL fnTypeStorage = TRUE;
UFN_CLIENT_NAME uname;
UFN_CLIENT_INFO uinfo;
DWORD dwReturn = 0;
_tcscpy(uname.szName, L"Mass_Storage_Class");
hDisk = GetUfncontroller();
if (hDisk == INVALID_HANDLE_VALUE)
{
RETAILMSG(1, (TEXT("invalid usb handle, error = %d/r/n"), GetLastError()));
}
if (DeviceIoControl(hDisk, IOCTL_UFN_GET_CURRENT_CLIENT, NULL, 0, &uinfo, sizeof(uinfo), &dwReturn, 0) && (dwReturn == sizeof(uinfo)))
{
if (_tcscmp(L"Mass_Storage_Class", uinfo.szName) == 0)
{
_tcscpy(uname.szName, L"Serial_Class");
fnTypeStorage = FALSE;
}
else
{
fnTypeStorage = TRUE;
}
}
if (!DeviceIoControl(hDisk, IOCTL_UFN_CHANGE_CURRENT_CLIENT, &uname, sizeof(uname), NULL, 0, NULL, NULL))
{
RETAILMSG(1, (TEXT("deviceiocontrol failed, error = %d/r/n"), GetLastError()));
}
else
{
LONG lResult = 0;
if(fnTypeStorage)
{
lResult = RegOpenKeyEx( HKEY_LOCAL_MACHINE, DRIVER_USB_KEY, 0, 0, &hOpenKey );
if(ERROR_SUCCESS == lResult)
{
lResult = RegSetValueEx(hOpenKey,DRIVER_USB_NAME,0,REG_SZ,(BYTE *)DRIVER_USB_VALUE_STORAGE,sizeof(DRIVER_USB_VALUE_STORAGE));
}
}
else
{
lResult = RegOpenKeyEx( HKEY_LOCAL_MACHINE, DRIVER_USB_KEY, 0, 0, &hOpenKey );
if(ERROR_SUCCESS == lResult)
{
lResult = RegSetValueEx(hOpenKey,DRIVER_USB_NAME,0,REG_SZ,(BYTE *)DRIVER_USB_VALUE_SERIAL,sizeof(DRIVER_USB_VALUE_SERIAL));
}
}
RegCloseKey( hOpenKey );
}
}