[英]Acessing a serial to USB device with I/O kit
我有以下問題：我有一個Wintec WBT-202 GPS設備，它能夠通過USB傳輸位置數據作為NMEA數據。 在這個USB內部它只是一個USB到串行橋，它使用標准的usbser.sys驅動程序在Windows下運行。
我的問題是讓它在Mac OS X下運行。
USB GPS鼠標的硬件使用Atmel AT91SAM7S256芯片，該芯片也負責USB接口。
Mac OS X下的問題沒有發生。 在/dev下沒有創建新的字符設備來使該設備可訪問。
在Windows下，使用標准驅動程序usbser.sys 。 只有一個.inf文件將vendorID和productID指向此驅動程序。 從在Windows上使用Snoopy Pro（USB嗅探軟件）我知道，一旦設備正確初始化，它就會將數據作為ASCII NMEA字符串發送，這就是我想要的。
問題1 Mac OS X是否有usbser.sys等價物？ 如果是，可以使用無代碼kext來確保驅動程序匹配正確嗎？
如果這不起作用，我會從用戶空間使用IOKit向設備發送和接收消息。 我仍然對這將如何工作有疑問，因為我不完全理解蘋果的文檔。 如果連接了USB設備，則會發生驅動程序匹配。 如果找不到驅動程序會發生什么。
問題2是否可以加載一些通用USB驅動程序，我可以在內核中與用戶空間“交談”？ 我怎么知道正確的驅動程序已加載？
問題3我看到在WWDC08中有一個“入門I / O Kit”會話有沒有辦法訪問這個會話視頻？
我附上了USBProbe的一些日志和I / O注冊表摘錄。
任何關於我如何開始哪些文檔提供一個體面的教程的評論將不勝感激。
我查看了Mac OS X Internals - Amit Singh的系統內部 ，Apple的文檔“I / O Kit入門”，“I / O Kit基礎指南”和USB私有數據示例。
附錄
USB探頭
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注冊表
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探測器登錄設備連接
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
編輯：在設備附加后附加來自console.app的日志文件摘錄
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
我從發布到Apple的USB郵件列表中得到的答案是Apple AppleUSBCDCACMData驅動程序有一個錯誤，它阻止了它的工作。 我在Apple的雷達上提出了一個錯誤，希望他們能盡快修復它。
看起來系統的CDC驅動程序正確匹配，應該創建/dev/ttyusbmodem* IIRC，如果這/dev/ttyusbmodem* ，我會檢查系統日志中的錯誤消息。
AppleUSBCDCACMData提到的錯誤有一種解決方法。 您需要為呼叫管理描述符分配接口。 你把它設置為00。
你展示：
Comm Class Call Management Functional Descriptor
Raw Descriptor (hex) 0000: 05 24 01 01 00
缺乏和分配。 使用ATMEL USB庫，它看起來像這樣：
// Class-specific call management functional descriptor`
{ sizeof(CDCCallManagementDescriptor),
CDCGenericDescriptor_INTERFACE,
CDCGenericDescriptor_CALLMANAGEMENT,
CDCCallManagementDescriptor_SELFCALLMANAGEMENT,
1 // <--needed for MacOS
}
如果您是USB驅動程序編程器，則應下載AppleUSBCDCDriver項目的源代碼，該項目包含AppleUSBCDCDriver.kext，AppleUSBCDCACMControl.kext，AppleUSBCDCACMData.kext，AppleUSBCDCECMControl.kext，AppleUSBCDCECMData.kext。
我可以保證的是，你肯定可以通過修復代碼並構建自己的驅動程序來解決這個問題。（記得改變驅動程序的類名。）
我可以確認的是，AppleUSBCDCDriver主要是根據標准通信設備類規范設計的，包括Apple開發團隊的考慮，這個問題不應該是一個bug。
在Mac OS上，驅動程序匹配主要是根據驅動程序的info.plist，就像Windows上的.inf文件一樣。
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