使用I / O套件访问串行至USB设备

Question

I have the following problem: I have a Wintec WBT-202 GPS device which has the ability to transmit the location data live as NMEA data over USB. Inside this USB it is just a USB to serial bridge which is run under Windows using the standard usbser.sys driver.

My problem is to get it working under Mac OS X.

The hardware the USB GPS mouse uses an Atmel AT91SAM7S256 chip which also is responsible for the USB interface.

The problem under Mac OS X there is nothing happening. There is no new character device created under /dev to make this device accessible.

Under Windows the standard driver usbser.sys is used. There is just an .inf file pointing the vendorID and productID to this driver. From using Snoopy Pro on Windows (a USB sniffing software) I know that once the device is properly initialized it sends the data as ASCII NMEA strings, which is all I want.

Question 1 Is there an usbser.sys equivalent for Mac OS X? If yes, could a codeless kext be used to make sure driver matching occurs properly?

If this would not work, I would use IOKit from user space to send and receive messages to the device. I still have questions of how this would work in detail, because I do not fully understand apple's documentation. If a USB device is connected, driver matching occurs. what happens if no driver is found.

Question 2 Could it be that then some generic USB driver is loaded to which I am able to "talk to" in the kernel from user space? How do I know that the right driver is loaded?

Question 3 I saw that there was a "getting started with I/O Kit" session in WWDC08 is there a way to get access to this session video?

I have appended some logs of USBProbe and the I/O registry excerpt.

Any comments about how I could start which documentation provides a decent tutorial would be greatly appreciated.

I have looked into Mac OS X Internals - A System Internals by Amit Singh, Apple's documentation "Getting started with I/O Kit", "I/O Kit Fundamentals Guide" and the USB private data sample.

APPENDIX

USB Probe

Full Speed device @ 8 (0xFD360000): .............................................   Communication device: "WINTEC WBT202 CDC"
    Port Information:   0x0019
           Captive
           External Device
           Connected
           Enabled
    Device Descriptor   
        Descriptor Version Number:   0x0200
        Device Class:   2   (Communication)
        Device Subclass:   0
        Device Protocol:   0
        Device MaxPacketSize:   8
        Device VendorID/ProductID:   0x03EB/0x6119   (Atmel Corporation)
        Device Version Number:   0x0100
        Number of Configurations:   1
        Manufacturer String:   0 (none)
        Product String:   1 "WINTEC WBT202 CDC"
        Serial Number String:   0 (none)
    Configuration Descriptor   
        Length (and contents):   67
            Raw Descriptor (hex)    0000: 09 02 43 00 02 01 00 C0  32 09 04 00 00 01 02 02  
            Raw Descriptor (hex)    0010: 00 00 05 24 00 10 01 05  24 01 01 00 04 24 02 02  
            Raw Descriptor (hex)    0020: 05 24 06 00 01 07 05 83  03 40 00 0A 09 04 01 00  
            Raw Descriptor (hex)    0030: 02 0A 00 00 00 07 05 01  02 40 00 00 07 05 82 02  
            Raw Descriptor (hex)    0040: 40 00 00 
        Number of Interfaces:   2
        Configuration Value:   1
        Attributes:   0xC0 (self-powered)
        MaxPower:   100 ma
        Interface #0 - Communications-Control   
            Alternate Setting   0
            Number of Endpoints   1
            Interface Class:   2   (Communications-Control)
            Interface Subclass;   2
            Interface Protocol:   0
            Comm Class Header Functional Descriptor   
                Raw Descriptor (hex)   0000: 05 24 00 10 01 
            Comm Class Call Management Functional Descriptor   
                Raw Descriptor (hex)   0000: 05 24 01 01 00 
            Comm Class Abstract Control Management Functional Descriptor   
                Raw Descriptor (hex)   0000: 04 24 02 02 
            Comm Class Union Functional Descriptor   
                Raw Descriptor (hex)   0000: 05 24 06 00 01 
            Endpoint 0x83 - Interrupt Input   
                Address:   0x83  (IN)
                Attributes:   0x03  (Interrupt no synchronization data endpoint)
                Max Packet Size:   64
                Polling Interval:   10 ms
        Interface #1 - Communications-Data/Unknown Comm Class Model   
            Alternate Setting   0
            Number of Endpoints   2
            Interface Class:   10   (Communications-Data)
            Interface Subclass;   0   (Unknown Comm Class Model)
            Interface Protocol:   0
            Endpoint 0x01 - Bulk Output   
                Address:   0x01  (OUT)
                Attributes:   0x02  (Bulk no synchronization data endpoint)
                Max Packet Size:   64
                Polling Interval:   0 ms
            Endpoint 0x82 - Bulk Input   
                Address:   0x82  (IN)
                Attributes:   0x02  (Bulk no synchronization data endpoint)
                Max Packet Size:   64
                Polling Interval:   0 ms

IO Registry

 8: WINTEC WBT202 CDC@fd360000  <class IOUSBDevice>
     AppleUSBCDC  <class AppleUSBCDC>
     IOUSBInterface@0  <class IOUSBInterface>
         AppleUSBCDCACMControl  <class AppleUSBCDCACMControl>
     IOUSBInterface@1  <class IOUSBInterface>
   bcdDevice   256 (0x100)
   bDeviceClass   2 (0x2)
   bDeviceProtocol   0 (0x0)
   bDeviceSubClass   0 (0x0)
   bMaxPacketSize0   8 (0x8)
   bNumConfigurations   1 (0x1)
   Bus Power Available   250 (0xfa)
   Device Speed   1 (0x1)
   idProduct   24857 (0x6119)
   idVendor   1003 (0x3eb)
   iManufacturer   0 (0x0)
   IOCFPlugInTypes   
       9dc7b780-9ec0-11d4-a54f-000a27052861   IOUSBFamily.kext/Contents/PlugIns/IOUSBLib.bundle
   IOGeneralInterest   IOCommand is not serializable
   IOUserClientClass   IOUSBDeviceUserClientV2
   iProduct   1 (0x1)
   iSerialNumber   0 (0x0)
   locationID   -46792704 (0xfd360000)
   Low Power Displayed   No
   non-removable   yes
   PortNum   6 (0x6)
   Requested Power   50 (0x32)
   sessionID   1167822359 (0x459b8e17459b8e17)
   USB Address   5 (0x5)
   USB Product Name   WINTEC WBT202 CDC

USB probe log on device attach

   12.719 [5]   AppleUSBHub[0x6805a00]::ProcessStatusChanged found (0x      40) in statusChangedBitmap
   12.719 [3]   AppleUSBHub[0x6805a00]::ChangeRaisedPowerState(+) now (1)
   12.719 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler: port 6 obtained runLock
   12.719 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler: calling GetPortStatus for port 6
   12.719 [5]   AppleUSBHub[0x6805a00]::powerChangeDone - spawning _checkForActivePortsThread
   12.719 [5]   AppleUSBEHCI[0x65ea000]::FindControlBulkEndpoint (inactive) - linking to active list: 65997c0
   12.719 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler - Hub 0xfd300000 port 6 - Initial status(0x0101)/change(0x0001)
   12.719 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler - port 6 - change 4 clearing feature 0x10.
   12.719 [5]   AppleUSBHub[0x6805a00]::ClearPortFeature port/feature (60010) - clearing
   12.719 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler - port 6 - status(0x0101) - change(0x0000) - before call to (4) handler function
   12.719 [5]   AppleUSBHubPort[0x6807200]::DefaultConnectionChangeHandler - handling port 6 changes (101,0).
   12.719 [5]   AppleUSBHubPort[0x6807200]::DefaultConnectionChangeHandler port (6) - waiting 100 ms before asserting reset
   12.819 [5]   AppleUSBHubPort[0x6807200]::DefaultConnectionChangeHandler - port 6 - no existing device found on port
   12.820 [4]   AppleUSBHubPort[0x6807200]::DefaultConnectionChangeHandler port 6 status(0101)/change(0000) - no error from GetPortStatus
   12.820 [5]   AppleUSBHubPort[0x6807200]::DefaultConnectionChangeHandler - port 6 - device detected, calling AddDevice
   12.820 [3]   AppleUSBHub[0x6805a00]::ChangeRaisedPowerState(+) now (2)
   12.820 [5]   AppleUSBHubPort[0x6807200]::DefaultConnectionChangeHandler - port 6 done, ending.
   12.820 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler - port 6 - err (0) on return from  call to (4) handler function
   12.820 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler: calling GetPortStatus for port 6
   12.820 [5]   ***** AppleUSBHubPort[0x6807200]::AddDevice - port 6 on hub at 0xfd300000 - start
   12.820 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler - Hub 0xfd300000 port 6 - Initial status(0x0101)/change(0x0000)
   12.820 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler - port 6 - err = 0 - done, releasing _runLock
   12.820 [3]   AppleUSBHub[0x6805a00]::ChangeRaisedPowerState(-) now (1)
   12.820 [3]   AppleUSBHub[0x6805a00]::DecrementOutstandingIO(269), outstandingIO(0), _interruptReadPending(false) - rearming read
   12.820 [5]   AppleUSBHub[0x6805a00]::DecrementOutstandingIO(269) - spawning _checkForActivePortsThread
   12.820 [5]   ***** AppleUSBHubPort[0x6807200]::AddDevice - port 6 on hub at 0xfd300000 - bus 0x65ea000 - acquiring dev zero lock
   12.820 [5]   AppleUSBEHCI[0x65ea000]::ProtectedDevZeroLock - about to obtain device zero lock
   12.820 [5]   AppleUSBEHCI[0x65ea000]::ProtectedDevZeroLock - not already locked - obtaining
   12.820 [5]   AppleUSBEHCI[0x65ea000]::ProtectedDevZeroLock - setting _devZeroLock to true
   12.820 [5]   AppleUSBEHCI[0x65ea000]: Acquired Device Zero
   12.820 [5]   ***** AppleUSBHubPort[0x6807200]::AddDevice - port 6 on hub at 0xfd300000 - resetting port
   12.820 [5]   AppleUSBHub[0x6805a00]::SetPortFeature port/feature (60004) - setting
   12.821 [5]   ***** AppleUSBHubPort[0x6807200]::AddDevice - port 6 on hub at 0xfd300000 - (err = 0) done - returning .
   12.821 [3]   AppleUSBHub[0x6805a00]::ChangeRaisedPowerState(-) now (0)
   12.879 [5]   AppleUSBHub[0x6805a00]::ProcessStatusChanged found (0x      40) in statusChangedBitmap
   12.879 [3]   AppleUSBHub[0x6805a00]::ChangeRaisedPowerState(+) now (1)
   12.879 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler: port 6 obtained runLock
   12.879 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler: delaying 100ms before first GetPortStatus after a reset of port 6
   12.879 [5]   AppleUSBHub[0x6805a00]::powerChangeDone - spawning _checkForActivePortsThread
   12.979 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler: calling GetPortStatus for port 6
   12.979 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler - Hub 0xfd300000 port 6 - Initial status(0x0103)/change(0x0010)
   12.979 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler - port 6 - change 1 clearing feature 0x14.
   12.979 [5]   AppleUSBHub[0x6805a00]::ClearPortFeature port/feature (60014) - clearing
   12.979 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler - port 6 - status(0x0103) - change(0x0000) - before call to (1) handler function
   12.979 [5]   ***** AppleUSBHubPort[0x6807200]::AddDeviceResetChangeHandler - port 6 on hub at 0xfd300000 - start - status(0x0103) change (0x0000)
   12.979 [5]   **1** AppleUSBHubPort[0x6807200]::AddDeviceResetChangeHandler - port 6 on hub at 0xfd300000 - delaying 10 ms
   12.989 [5]   **2** AppleUSBHubPort[0x6807200]::AddDeviceResetChangeHandler - port 6 on hub at 0xfd300000 - found full speed device
   12.989 [5]   **2** AppleUSBHubPort[0x6807200]::AddDeviceResetChangeHandler - port 6 on hub at 0xfd300000 - configuring dev zero
   12.989 [5]   AppleUSBEHCI[0x65ea000]::ConfigureDeviceZero, new method called with hub:3, port:6
   12.989 [5]   AppleUSBEHCI[0x65ea000]::CreateDevice, high speed ancestor hub:3, port:6
   12.989 [5]   AppleUSBEHCI[0x65ea000]::DoCreateEP, high speed ancestor hub:3, port:6
   12.989 [3]   AppleUSBEHCI[0x65ea000]::UIMCreateControlEndpoint(0, 0, 8, 1 @(3, 6))
   12.989 [5]   **3** AppleUSBHubPort[0x6807200]::AddDeviceResetChangeHandler - port 6 on hub at 0xfd300000 - getting dev zero desc
   12.990 [5]   **3** AppleUSBHubPort[0x6807200]::AddDeviceResetChangeHandler - port 6, using 8 for maxPacketSize
   12.992 [5]   **5** AppleUSBHubPort[0x6807200]::AddDeviceResetChangeHandler - port 6, Releasing DeviceZero after successful SetAddress to 5
   12.992 [5]   AppleUSBEHCI[0x65ea000]::UIMDeleteEndpoint: unlinking async endpoint
   12.993 [5]   AppleUSBEHCI[0x65ea000]::UIMDeleteEndpoint: Deallocating 0x68bd700
   12.993 [5]   AppleUSBEHCI[0x65ea000]::ProtectedDevZeroLock - about to release device zero lock
   12.993 [5]   AppleUSBEHCI[0x65ea000]::ProtectedDevZeroLock - releasing lock
   12.993 [5]   AppleUSBEHCI[0x65ea000]::ProtectedDevZeroLock - wakeup done
   12.993 [5]   AppleUSBEHCI[0x65ea000]:: Released Device Zero
   12.993 [5]   AppleUSBEHCI[0x65ea000]::CreateDevice, new method called with hub:3, port:6
   12.993 [5]   AppleUSBEHCI[0x65ea000]::CreateDevice, high speed ancestor hub:3, port:6
   12.993 [5]   AppleUSBEHCI[0x65ea000]::CreateDevice: addr=5, speed=full, power=500
   12.993 [5]   IOUSBDevice @ 5 (500mA available, full speed)
   12.993 [5]   AppleUSBEHCI[0x65ea000]::DoCreateEP, high speed ancestor hub:3, port:6
   12.993 [3]   AppleUSBEHCI[0x65ea000]::UIMCreateControlEndpoint(5, 0, 8, 1 @(3, 6))
   12.993 [5]   IOUSBDevice[0xd335c00]::GetDeviceDescriptor (size 18)
   12.994 [5]   IOUSBDevice[0xd335c00]::GetStringDescriptor Got string descriptor 1, length 36, got 36
   12.994 [5]   **10** AppleUSBHubPort[0x6807200]::AddDeviceResetChangeHandler -  port 6, at addr: 5, Successful
   12.994 [5]   AppleUSBHub[0x6805a00]::GetPortInformation  for port[6]
   12.995 [5]   WINTEC WBT202 CDC[0xd335c00]::GetDeviceInformation  Hub device name is HubDevice at USB address 3
   12.995 [5]   AppleUSBHub[0x6656800]::GetPortInformation  for port[3]
   12.995 [5]   AppleUSBHubPort[0x6807200]::AddDeviceResetChangeHandler - Port 6 of Hub at 0xfd300000 (USB Address: 5), calling registerService for device WINTEC WBT202 CDC
   12.995 [5]   AppleUSBHubPort[0x6807200]::AddDeviceResetChangeHandler - port 6, err = 0, ALL DONE
   12.995 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler - port 6 - err (0) on return from  call to (1) handler function
   12.995 [5]   AppleUSBHubPort[0x6807200]::PortStatusChangedHandler - port 6 - err = 0 - done, releasing _runLock
   12.995 [3]   AppleUSBHub[0x6805a00]::ChangeRaisedPowerState(-) now (0)
   12.995 [3]   AppleUSBHub[0x6805a00]::DecrementOutstandingIO(274), outstandingIO(0), _interruptReadPending(false) - rearming read
   12.995 [5]   AppleUSBHub[0x6805a00]::DecrementOutstandingIO(274) - spawning _checkForActivePortsThread
   12.999 [5]   Finding device driver for WINTEC WBT202 CDC, matching personality using com.apple.driver.AppleUSBCDC, score: 69000, wildCard = 0
   12.999 [5]   Finding device driver for WINTEC WBT202 CDC, matching personality using com.apple.iokit.IOUSBUserClient, score: 106999, wildCard = 3
   13.002 [5]   WINTEC WBT202 CDC[0xd335c00]::handleOpen - [0xdd78880] is not an IOUSBInterface
   13.002 [5]   WINTEC WBT202 CDC[0xd335c00]::TakeGetConfigLock - calling through to ChangeGetConfigLock
   13.002 [5]   WINTEC WBT202 CDC[0xd335c00]::ChangeGetConfigLock - setting _GETCONFIGLOCK to true
   13.002 [5]   WINTEC WBT202 CDC[0xd335c00]::GetFullConfigurationDescriptor - Index (0) - getting first 4 bytes of config descriptor
   13.002 [5]   WINTEC WBT202 CDC[0xd335c00]::GetConfigDescriptor (length: 4)
   13.002 [5]   WINTEC WBT202 CDC[0xd335c00]::GetFullConfigurationDescriptor - Index (0) - getting full 67 bytes of config descriptor
   13.002 [5]   WINTEC WBT202 CDC[0xd335c00]::GetConfigDescriptor (length: 67)
   13.003 [5]   WINTEC WBT202 CDC[0xd335c00]::ReleaseGetConfigLock - calling through to ChangeGetConfigLock
   13.003 [5]   WINTEC WBT202 CDC[0xd335c00]::ChangeGetConfigLock - setting _GETCONFIGLOCK to false and calling commandWakeup
   13.503 [5]   WINTEC WBT202 CDC[0xd335c00]::TerminateInterfaces interfaceList 0 terminate: 1
   13.503 [5]   WINTEC WBT202 CDC[0xd335c00]::SetConfiguration to 1
   13.504 [5]   WINTEC WBT202 CDC[0xd335c00]::SetConfiguration  Found InterfaceDescription[0] = 0x68bc889
   13.504 [5]   WINTEC WBT202 CDC[0xd335c00]::SetConfiguration  Found InterfaceDescription[1] = 0x68bc8ac
   13.504 [5]   WINTEC WBT202 CDC[0xd335c00]::RegisterInterfaces interfaceArray 0x6de9b00
   13.504 [5]   WINTEC WBT202 CDC[0xd335c00]::RegisterInterfaces  matching to interface = 0x8261700
   13.553 [5]   Finding driver for interface #0 of WINTEC WBT202 CDC, matching personality using com.apple.iokit.IOUSBUserClient, score: 104999, wildCard = 5
   13.567 [5]   Finding driver for interface #0 of WINTEC WBT202 CDC, matching personality using com.apple.driver.AppleUSBCDCACMControl, score: 50000, wildCard = 0
   13.570 [5]   AppleUSBEHCI[0x65ea000]::DoCreateEP, high speed ancestor hub:3, port:6
   13.570 [5]   AppleUSBEHCI[0x65ea000]: UIMCreateInterruptEndpoint endpoint does NOT exist (this is normal)
   13.570 [5]   AppleUSBEHCI[0x65ea000]::AllocateInterruptBandwidth - pED[0x68bd780] _speed(1)
   13.570 [3]   AppleUSBEHCITTInfo[0x682b400]::AllocatePeriodicBandwidth: pSPE[0x6f8ae40]
   13.570 [5]   AppleUSBEHCISplitPeriodicEndpoint[0x6f8ae40]::FindStartFrameAndStartTime - _FSBytesUsed (78)
   13.570 [5]   AppleUSBEHCISplitPeriodicEndpoint[0x6f8ae40]::FindStartFrameAndStartTime - using Start Time entry found - _startFrame(1) _startTime(36)
   13.570 [5]   AppleUSBEHCI[0x65ea000]::AllocateInterruptBandwidth - returning 0x0(success)
   13.571 [5]   AppleUSBHub[0x6805a00]::powerChangeDone - spawning _checkForActivePortsThread
   13.573 [5]   WINTEC WBT202 CDC[0xd335c00]::RegisterInterfaces  matching to interface = 0xd337700
   13.621 [5]   Finding driver for interface #1 of WINTEC WBT202 CDC, matching personality using com.apple.iokit.IOUSBUserClient, score: 104999, wildCard = 5
   13.636 [5]   Finding driver for interface #1 of WINTEC WBT202 CDC, matching personality using com.apple.driver.AppleUSBCDCACMData, score: 50000, wildCard = 0
   14.024 [5]   Finding driver for interface #1 of WINTEC WBT202 CDC, matching personality using com.apple.driver.AppleUSBCDCACMData, score: 50000, wildCard = 0
   14.075 [5]   Finding driver for interface #1 of WINTEC WBT202 CDC, matching personality using com.apple.iokit.IOUSBUserClient, score: 104999, wildCard = 5
   14.089 [5]   Finding driver for interface #1 of WINTEC WBT202 CDC, matching personality using com.apple.driver.AppleUSBCDCACMData, score: 50000, wildCard = 0
   14.090 [5]   Finding driver for interface #1 of WINTEC WBT202 CDC, matching personality using com.apple.driver.AppleUSBCDCECMData, score: 50000, wildCard = 0
   14.266 [5]   Finding driver for interface #1 of WINTEC WBT202 CDC, matching personality using com.apple.driver.AppleUSBCDCECMData, score: 50000, wildCard = 0
   14.315 [5]   Finding driver for interface #1 of WINTEC WBT202 CDC, matching personality using com.apple.iokit.IOUSBUserClient, score: 104999, wildCard = 5
   14.330 [5]   Finding driver for interface #1 of WINTEC WBT202 CDC, matching personality using com.apple.driver.AppleUSBCDCACMData, score: 50000, wildCard = 0
   14.330 [5]   Finding driver for interface #1 of WINTEC WBT202 CDC, matching personality using com.apple.driver.AppleUSBCDCECMData, score: 50000, wildCard = 0
   14.334 [5]   WINTEC WBT202 CDC[0xd335c00]::SetConfiguration  returning success

EDIT: appended the log file excerpt from console.app after device attach

16.02.11 09:05:55   kernel  0        0 AppleUSBCDCACMControl: getFunctionalDescriptors - Descriptors are incorrect, checking...
16.02.11 09:05:55   kernel  0        1 AppleUSBCDCACMData: start - Find CDC driver for data interface failed

Answer 1

The answer I got from posting to Apple's USB mailing list is that the Apple AppleUSBCDCACMData driver has a bug in it preventing from doing its work. I filed a bug on Apple's radar and hope they will fix it soon.

Answer 2

看起来系统的CDC驱动程序正确匹配，应该创建/dev/ttyusbmodem* IIRC，如果这/dev/ttyusbmodem* ，我会检查系统日志中的错误消息。

Answer 3

There is a workaround for the bug mentioned in AppleUSBCDCACMData . You need to assign an interface to the call management descriptor. You have it set to 00.

You show:

Comm Class Call Management Functional Descriptor
Raw Descriptor (hex) 0000: 05 24 01 01 00

That lacks and assignment. Using the ATMEL USB libraries, it would look like this:

// Class-specific call management functional descriptor`
{ sizeof(CDCCallManagementDescriptor),
CDCGenericDescriptor_INTERFACE,
CDCGenericDescriptor_CALLMANAGEMENT,
CDCCallManagementDescriptor_SELFCALLMANAGEMENT,
1 // <--needed for MacOS
}

Answer 4

If u are a USB Driver programmer, u should download the source code for AppleUSBCDCDriver project, which contains AppleUSBCDCDriver.kext, AppleUSBCDCACMControl.kext, AppleUSBCDCACMData.kext, AppleUSBCDCECMControl.kext, AppleUSBCDCECMData.kext.

What i can promise is that, u definitly could solve this issue by fix the code and build your own driver.(Remember to change the driver's class name.)

What i can confirm is that, the AppleUSBCDCDriver is mainly designed according to the Standard Communication Device Class Specification, and including the consideration by Apple Developement Team, and this issue should not be a bug.

On Mac OS, driver matching is mainly according to the info.plist of the driver, just like .inf file on Windows.