Question

我正在使用macOS上的USB串行设备。

如何使用IOKit在macOS上检测USB串行设备的BSD（unix）名称？我想获取设备名称，例如：“ IODialinDevice” =“ /dev/tty.usbmodemMyDeviceName”

我的USB设备是USB串行COM端口。我也想检测设备何时连接到机器。

我可以检测到何时连接了具有我的VID和PID的新USB设备。这段代码允许我这样做

CFMutableDictionaryRef keywordDict = IOServiceMatching(kIOSerialBSDServiceValue);

kern_return_t result = IOServiceGetMatchingServices(kIOMasterPortDefault, keywordDict, &iterator);

while ((port = IOIteratorNext(iterator)))
{
        io_object_t parent = 0;                     
        io_object_t current_device = port;
        while (KERN_SUCCESS == IORegistryEntryGetParentEntry(current_device, kIOServicePlane, &parent))
        {
            CFTypeRef vendor_Id = IORegistryEntryCreateCFProperty(parent, CFSTR(kUSBVendorID), kCFAllocatorDefault, 0);
            CFTypeRef pr_Id = IORegistryEntryCreateCFProperty(parent, CFSTR(kUSBProductID), kCFAllocatorDefault, 0);

            if((vendor_id==MY_VENDOR_ID) && (pr_ID==MY_PRODUCT_ID))
            {
                // MY SERIAL DEVICE DETECTED !! 
                CFTypeRef deviceName = IORegistryEntryCreateCFProperty(device, key, CFSTR(kIOTTYDeviceKey), 0);
                CFTypeRef callOutDevice = IORegistryEntryCreateCFProperty(device, key, CFSTR(kIOCalloutDeviceKey), 0);
                CFTypeRef dialInDevice = IORegistryEntryCreateCFProperty(device, key, CFSTR(kIODialinDeviceKey), 0);

            }
        }
}

但是此代码不允许我检测新设备的问题。我只是在这里枚举现有的kIOSerialBSDServiceValue设备，然后检查父VID和PID 如果父母有MY_VID和MY_PID，则假定我找到了正确的串行设备。

另一个代码使我可以检测到新的USB设备

这是Apple示例LUSBPrivateDataSample.c 我可以通过以下代码使用VID和PID检测我的设备：

   int main()
   {
    ...
    ...
    ...

    // Create a CFNumber for the idVendor and set the value in the dictionary
    numberRef = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &usbVendor);
    CFDictionarySetValue(matchingDict, 
                         CFSTR(kUSBVendorID), 
                         numberRef);
    CFRelease(numberRef);

    // Create a CFNumber for the idProduct and set the value in the dictionary
    numberRef = CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &usbProduct);
    CFDictionarySetValue(matchingDict, 
                         CFSTR(kUSBProductID), 
                         numberRef);
    CFRelease(numberRef);

    ...
    ...
    ...

        // Now set up a notification to be called when a device is first matched by I/O Kit.
    kr = IOServiceAddMatchingNotification(gNotifyPort,                  // notifyPort
                                          kIOFirstMatchNotification,    // notificationType
                                          matchingDict,                 // matching
                                          DeviceAdded,                  // callback
                                          NULL,                         // refCon
                                          &gAddedIter                   // notification
                                          );    

    }

    void DeviceAdded(void *refCon, io_iterator_t iterator)
    {
        io_service_t        usbDevice;
        while ((usbDevice = IOIteratorNext(iterator)))
        {
                // I have device here but I can't get IODialinDevice device name 
        }
    }

此代码的问题是我无法获得IODialinDevice设备名称我还检查了此usbDevice的所有子节点。它们都不包含IODialinDevice属性，或者都不是kIOSerialBSDServiceValue设备。

看起来我做错了。看起来串行设备和USB分别位于不同的IOKit注册表分支中。问题是如何使用IODialinDevice（“ /dev/tty.usbmodemMyDeviceName”）属性将VID和PID标识的USB设备转换为串行设备（kIOSerialBSDServiceValue）。

任何帮助表示赞赏！

更新：这是ioreg树：
我可以在应用程序中检测到CDC ACM数据设备。（此树中的顶部设备）在ioreg，我看到了这张照片。因此，存在具有IODialinDevice属性的子代，AppleUSBACMData和IOSerialBSDClient。但是我无法在应用程序中检测到AppleUSBACMData和IOSerialBSDClient。可能是因为AppleUSBACMData和IOSerialBSDClient不是设备，而是USB接口或USB端点。所以这是我的问题。

+-o CDC ACM Data@3  <class IOUSBHostInterface, id 0x100090fff, registered, matched, active, busy 0 (514 ms), retain 7>
  | {
  |   "USBPortType" = 0
  |   "IOCFPlugInTypes" = {"2d9786c6-9ef3-11d4-ad51-000a27052861"="IOUSBFamily.kext/Contents/PlugIns/IOUSBLib.bundle"}
  |   "Product Name" = "DevName"
  |   "bcdDevice" = 1044
  |   "USBSpeed" = 3
  |   "idProduct" = 260
  |   "bConfigurationValue" = 1
  |   "bInterfaceSubClass" = 0
  |   "locationID" = 338886656
  |   "IOGeneralInterest" = "IOCommand is not serializable"
  |   "IOServiceLegacyMatchingRegistryID" = 4295561221
  |   "IOClassNameOverride" = "IOUSBInterface"
  |   "AppleUSBAlternateServiceRegistryID" = 4295561221
  |   "idVendor" = 7777
  |   "bInterfaceProtocol" = 0
  |   "bAlternateSetting" = 0
  |   "bInterfaceNumber" = 3
  |   "bInterfaceClass" = 10
  | }
  | 
  +-o AppleUSBACMData  <class AppleUSBACMData, id 0x100091018, registered, matched, active, busy 0 (0 ms), retain 6>
    | {
    |   "IOClass" = "AppleUSBACMData"
    |   "CFBundleIdentifier" = "com.apple.driver.usb.cdc.acm"
    |   "IOProviderClass" = "IOUSBHostInterface"
    |   "IOTTYBaseName" = "usbmodem"
    |   "idProduct" = 260
    |   "IOProbeScore" = 49999
    |   "bInterfaceSubClass" = 0
    |   "HiddenPort" = Yes
    |   "IOMatchCategory" = "IODefaultMatchCategory"
    |   "idVendor" = 7777
    |   "IOTTYSuffix" = "DevName_B3"
    |   "bInterfaceClass" = 10
    | }
    | 
    +-o IOSerialBSDClient  <class IOSerialBSDClient, id 0x100091020, registered, matched, active, busy 0 (0 ms), retain 5>
    {
       "IOClass" = "IOSerialBSDClient" 
        "CFBundleIdentifier" = "com.apple.iokit.IOSerialFamily"
        "IOProviderClass" = "IOSerialStreamSync"
        "IOTTYBaseName" = "usbmodem"
        "IOSerialBSDClientType" = "IORS232SerialStream"
        "IOProbeScore" = 1000
        "IOCalloutDevice" = "/dev/cu.usbmodemDevName_B3"
        "IODialinDevice" = "/dev/tty.usbmodemDevName_B3"
        "IOMatchCategory" = "IODefaultMatchCategory"
        "IOTTYDevice" = "usbmodemDevName_B3"
        "IOResourceMatch" = "IOBSD"
        "IOTTYSuffix" = "DevName_B3"
    }

Answer 1

解决方案非常简单。它总是在我的桌子上。您应该订阅以接收有关新kIOSerialBSDServiceValue设备出现在系统中的通知像这样。该代码也基于Apple USBPrivateDataSample.c

https://developer.apple.com/library/archive/samplecode/USBPrivateDataSample/Introduction/Intro.html#//apple_ref/doc/uid/DTS10000456

CFMutableDictionaryRef matchingDict = IOServiceMatching(kIOSerialBSDServiceValue);
....
    // Now set up a notification to be called when a device is first matched by I/O Kit.
kr = IOServiceAddMatchingNotification(gNotifyPort,                  // notifyPort
                                      kIOFirstMatchNotification,    // notificationType
                                      matchingDict,                 // matching
                                      DeviceAdded,                  // callback
                                      NULL,                         // refCon
                                      &gAddedIter                   // notification
                                      );

当您获得kIOSerialBSDServiceValue（在DeviceAdded（）函数中）时，在IOKit树上向上遍历（使用IORegistryEntryGetParentEntry），直到找到您的VID和PID。（请参阅我的第一个代码片段。）如果找不到并且设备树已结束，则这不是您的设备。

IOKIT使用PID和VID为USB串行设备检测BSD（unix）名称

1 个答案: