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Is it possible to communicate with peripherals through the TypeC port of Apple 15 or above mobile phones?
I need to implement an app that exchanges data with peripherals through TypeC on Apple 15 phones, but I have two questions that I need to ask for help: Which library is used to communicate with peripherals through the TypeC port of the Apple mobile phone? Do peripherals need to pass MFi authentication before they can communicate with the App?
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175
Jun ’25
Technical Inquiry Regarding DriverKit USB Serial Communication Issues on iPadOS
I am currently developing a kiosk system that incorporates an iPad along with a custom peripheral device. The two components are intended to communicate via USB serial. I have encountered a critical issue while working with the official DriverKit sample code provided at the following link: https://developer.apple.com/documentation/driverkit/communicating-between-a-driverkit-extension-and-a-client-app Model info : iPad Pro 12.9-inch (5th generation / M1 chipset) iPadOS 18.4.1 App Stops Functioning After Repeated Builds When I first build and run the sample code without any modifications, it works as expected. However, after making changes and running the app repeatedly on the iPad, it eventually reaches a state where the app stops functioning completely — no logs are printed, and device communication fails. Reinstalling the app or rebooting the iPad does not resolve the issue. Even when I revert to the original, unmodified sample code, the problem persists. Surprisingly, if I generate a new Bundle Identifier, the app functions normally again. I would like to ask: What could be causing this behavior? Have similar cases been reported before? For your reference, I’ve attached a video demonstrating the issue and the source code used during the recording: Source Code: https://drive.google.com/file/d/14whvWwuhrmS5VoR3sSKyNT-GpTPC_c_8/view?usp=sharing Video: https://drive.google.com/file/d/1SfqIkEphSDrvg-CKS6KBcJ1VBP3cPqCC/view?usp=sharing Request for USB Serial Communication Reference Currently, due to the issue above, I am unable to obtain a device instance at all. Even assuming this is resolved, I noticed that the sample code does not include any implementation or reference material for USB serial communication itself. Is there any official sample code or documentation available that demonstrates USB serial communication between an iPad and an external device using DriverKit? Difficulty Debugging Due to Missing os_log Output Another challenge I'm facing is the inability to view os_log output while connecting the USB device to the iPad. This significantly hinders the debugging process during DriverKit development. Are there any recommended or supported methods for accessing logs and debugging effectively in this environment?
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120
Jun ’25
iTunes Asks for an update that doesn't exist
I want to update my iPhone 15 Pro to iOS 26 from iOS 18.5. I downloaded ipsw firmware. But iTunes and Apple Devices App requires update version of app for update to iOS 26. But I use last version of iTunes / Apple Devices, which was realised 2 May, 2025. That mean Apple need to update their apps for adaptation it to iOS 26 update?
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104
Jun ’25
BLE Connection Failure with iPad A16 and Silicon Labs Gecko SDK 3.x Devices
We're seeing a consistent issue where iPads with the A16 chip fail to connect to our BLE device, which uses a Silicon Labs chip running Gecko SDK 3.x. All other Apple devices — including older iPads and iPhones — connect without any problems. According to Silicon Labs, the issue stems from the iPad A16 sending an LL_CHANNEL_REPORTING_IND message (opcode 0x28) during connection establishment: Per Silicon Labs: "Currently the iPad 16 will send a message for LL_CHANNEL_REPORTING_IND (opcode 0x28). This is a feature that is not supported in Gecko SDK 3.x. Shortly after, the BLE module responds with an 'Unknown Response' (opcode 0x07), indicating that it does not support opcode 0x28 After this exchange the iPad stops sending meaningful transactions to the BLE module and eventually closes the connection. The BLE Module is responding to this unknown request as specified in the BT Core Spec Volume 6 Part B." Unfortunately, the firmware on these BLE modules cannot be updated remotely, and we've already shipped several thousand units to customers. Given how widely Silicon Labs' BLE modules are deployed, we suspect this issue could be affecting many other developers and products as well. We’re hoping Apple might offer a workaround or allow us access — even internally or unofficially — to suppress or bypass this feature in CoreBluetooth for this specific scenario. For example, is there a way to disable LL_CHANNEL_REPORTING_IND or instruct the stack to ignore the unknown response from the peripheral? We’re open to any workaround via CoreBluetooth (even private APIs or entitlements, if necessary) that would allow us to preserve compatibility without a mass recall. If there's an Apple engineer monitoring this, we'd be extremely grateful for guidance or escalation. Thank you!
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206
Jul ’25
DEXT crashes when app starting
We have developed the driver for the ProCapture video capture card based on PCIDriverKit. The App can communicate with the driver through the UserClient API. Currently, there is an issue where, when the App starts, there is a small probability that it causes a driver crash. However, the crash stack trace does not point to our code but appears to be within the PCIDriverKit framework. We have spent several weeks debugging but still cannot identify the root cause of the crash. Could you please review the crash log and suggest any methods to help pinpoint the issue? com.magewell.ProCaptureDriver-2025-09-15-153522.ips com.magewell.ProCaptureDriver-2025-09-15-082500.ips
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198
Oct ’25
DriverKit. Plug/unplug test leads to MacOS panic
Dear Apple engineers, We have developed a DriverKit (DEXT) driver for an HBA RAID controller. The RAID controller is connected to hosts through Thunderbolt (PCIe port of the Thunderbolt controller). We do plug/unplug tests to verify the developed driver. The test always fails in about 100 cycles with a MacOS crash (panic). The panic contains “LLC Bus error (Unavailable) from cpu0: FAR=0xa40100008 LLC_ERR_STS/ADR/INF=0x80/0x300480a40100008/0x1400000005 addr=0xa40100008 cmd=0x18(ACC_CIFL2C_CMD_RD_LD: request for load miss in E or S state)” At first we assumed that the issue is with hardware. But we did this test on different hosts (MacMini M3 and M4) with different units of our device. The error points to the same physical address FAR=0xa40100008 even if the hosts are different. The 2 full panic logs are attached (one for M4, another one for M3 host). Could you share your understanding of the crash and give any hints on how we can fix it? Please let us know if you need any additional data. Thank you M3 panic: https://drive.google.com/file/d/1GJXd3tTW6ajdrHpFsJxO_tWWYKYIgcMc/view?usp=share_link M4 panic: https://drive.google.com/file/d/1SU-3aBSdhLsyhhxsLknzw9wGvBQ9TbJC/view?usp=share_link
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182
Oct ’25
How to allocate contiguous memory in DriverKit?
We want to allocate a block of contiguous memory (≤1M) for audio ring DMA usage, but we haven't found any explicit method in the DriverKit documentation for allocating contiguous memory. I'm aware that IOBufferMemoryDescriptor::Create can be used in DriverKit to allocate memory and share it with user space. However, is the allocated memory physically contiguous? Can it guarantee that when I subsequently call PrepareForDMA in IODMACommand, there will be only one segment? Could you please help review this? Thank you!
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130
Oct ’25
Disable ISO15693Tag Popup
Dear Apple CS, I’m working with NFC ISO15693 tags using NFCTagReaderSession / NFCISO15693Tag, and I’d like to read these tags in the background if possible. Is there any way to read this tag type without triggering the system NFC popup that iOS normally shows? Please note it will not be a public app, the app is meant for internal use for our employees only. is there an option to submit a special request for this use case? Thank you in advance!
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106
2w
RFID read
Hi! Following this ticket: https://developer.apple.com/forums/thread/808764?page=1#868010022 Is there any way to use the hardware RFID reading capabilities of an iPhone to read ISO15693 RF tags silently, and without a UI pop-up? Perhaps using other native iOS libraries than the NFC library? If not, is there a way for a business to request this feature be allowed in internally used apps only?
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77
1w
Implementing a virtual serial port using DriverKit/SerialDriverKit
I'm trying to implement a virtual serial port driver for my ham radio projects which require emulating some serial port devices and I need to have a "backend" to translate the commands received by the virtual serial port into some network-based communications. I think the best way to do that is to subclass IOUserSerial? Based on the available docs on this class (https://developer.apple.com/documentation/serialdriverkit/iouserserial), I've done the basic implementation below. When the driver gets loaded, I can see sth like tty.serial-1000008DD in /dev and I can use picocom to do I/O on the virtual serial port. And I see TxDataAvailable() gets called every time I type a character in picocom. The problems are however, firstly, when TxDataAvailable() is called, the TX buffer is all-zero so although the driver knows there is some incoming data received from picocom, it cannot actually see the data in neither Tx/Rx buffers. Secondly, I couldn't figure out how to notify the system that there are data available for sending back to picocom. I call RxDataAvailable(), but nothing appears on picocom, and RxFreeSpaceAvailable() never gets called back. So I think I must be doing something wrong somewhere. Really appreciate it if anyone could point out how should I fix it, many thanks! VirtualSerialPortDriver.cpp: constexpr int bufferSize = 2048; using SerialPortInterface = driverkit::serial::SerialPortInterface; struct VirtualSerialPortDriver_IVars {     IOBufferMemoryDescriptor *ifmd, *rxq, *txq;     SerialPortInterface *interface;     uint64_t rx_buf, tx_buf;     bool dtr, rts; }; bool VirtualSerialPortDriver::init() {     bool result = false;     result = super::init();     if (result != true)     {         goto Exit;     }     ivars = IONewZero(VirtualSerialPortDriver_IVars, 1);     if (ivars == nullptr)     {         goto Exit;     }     kern_return_t ret;     ret = ivars->rxq->Create(kIOMemoryDirectionInOut, bufferSize, 0, &ivars->rxq);     if (ret != kIOReturnSuccess) {         goto Exit;     }     ret = ivars->txq->Create(kIOMemoryDirectionInOut, bufferSize, 0, &ivars->txq);     if (ret != kIOReturnSuccess) {         goto Exit;     }     IOAddressSegment ioaddrseg;     ivars->rxq->GetAddressRange(&ioaddrseg);     ivars->rx_buf = ioaddrseg.address;     ivars->txq->GetAddressRange(&ioaddrseg);     ivars->tx_buf = ioaddrseg.address;     return true; Exit:     return false; } kern_return_t IMPL(VirtualSerialPortDriver, HwActivate) {     kern_return_t ret;     ret = HwActivate(SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         goto Exit;     }     // Loopback, set CTS to RTS, set DSR and DCD to DTR     ret = SetModemStatus(ivars->rts, ivars->dtr, false, ivars->dtr);     if (ret != kIOReturnSuccess) {         goto Exit;     } Exit:     return ret; } kern_return_t IMPL(VirtualSerialPortDriver, HwDeactivate) {     kern_return_t ret;     ret = HwDeactivate(SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         goto Exit;     } Exit:     return ret; } kern_return_t IMPL(VirtualSerialPortDriver, Start) {     kern_return_t ret;   ret = Start(provider, SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         return ret;     }     IOMemoryDescriptor *rxq_, *txq_;     ret = ConnectQueues(&ivars->ifmd, &rxq_, &txq_, ivars->rxq, ivars->txq, 0, 0, 11, 11);     if (ret != kIOReturnSuccess) {         return ret;     }     IOAddressSegment ioaddrseg;     ivars->ifmd->GetAddressRange(&ioaddrseg);     ivars->interface = reinterpret_cast<SerialPortInterface*>(ioaddrseg.address);     SerialPortInterface &intf = *ivars->interface;     ret = RegisterService();     if (ret != kIOReturnSuccess) {         goto Exit;     }     TxFreeSpaceAvailable(); Exit:     return ret; } void IMPL(VirtualSerialPortDriver, TxDataAvailable) {     SerialPortInterface &intf = *ivars->interface;     // Loopback     // FIXME consider wrapped case     size_t tx_buf_sz = intf.txPI - intf.txCI;     void *src = reinterpret_cast<void *>(ivars->tx_buf + intf.txCI); //    char src[] = "Hello, World!";     void *dest = reinterpret_cast<void *>(ivars->rx_buf + intf.rxPI);     memcpy(dest, src, tx_buf_sz);     intf.rxPI += tx_buf_sz;     RxDataAvailable();     intf.txCI = intf.txPI;     TxFreeSpaceAvailable();     Log("[TX Buf]: %{public}s", reinterpret_cast<char *>(ivars->tx_buf));     Log("[RX Buf]: %{public}s", reinterpret_cast<char *>(ivars->rx_buf)); // dmesg confirms both buffers are all-zero     Log("[TX] txPI: %d, txCI: %d, rxPI: %d, rxCI: %d, txqoffset: %d, rxqoffset: %d, txlogsz: %d, rxlogsz: %d",         intf.txPI, intf.txCI, intf.rxPI, intf.rxCI, intf.txqoffset, intf.rxqoffset, intf.txqlogsz, intf.rxqlogsz); } void IMPL(VirtualSerialPortDriver, RxFreeSpaceAvailable) {     Log("RxFreeSpaceAvailable() called!"); } kern_return_t   IMPL(VirtualSerialPortDriver,HwResetFIFO){     Log("HwResetFIFO() called with tx: %d, rx: %d!", tx, rx);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwSendBreak){     Log("HwSendBreak() called!");     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramUART){     Log("HwProgramUART() called, BaudRate: %u, nD: %d, nS: %d, P: %d!", baudRate, nDataBits, nHalfStopBits, parity);     kern_return_t ret = kIOReturnSuccess;     return ret; }      kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramBaudRate){     Log("HwProgramBaudRate() called, BaudRate = %d!", baudRate);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramMCR){     Log("HwProgramMCR() called, DTR: %d, RTS: %d!", dtr, rts);     ivars->dtr = dtr;     ivars->rts = rts;     kern_return_t ret = kIOReturnSuccess; Exit:     return ret; } kern_return_t  IMPL(VirtualSerialPortDriver, HwGetModemStatus){     *cts = ivars->rts;     *dsr = ivars->dtr;     *ri = false;     *dcd = ivars->dtr;     Log("HwGetModemStatus() called, returning CTS=%d, DSR=%d, RI=%d, DCD=%d!", *cts, *dsr, *ri, *dcd);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramLatencyTimer){     Log("HwProgramLatencyTimer() called!");     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramFlowControl){     Log("HwProgramFlowControl() called! arg: %u, xon: %d, xoff: %d", arg, xon, xoff);     kern_return_t ret = kIOReturnSuccess; Exit:     return ret; }
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0
2.1k
Feb ’25
Looking for USBSerialDriver sample code
I would like to write a driver that supports our custom USB-C connected device, which provides a serial port interface. USBSerialDriverKit looks like the solution I need. Unfortunately, without a decent sample, I'm not sure how to accomplish this. The DriverKit documentation does a good job of telling me what APIs exist but it is very light on semantic information and details about how to use all of these API elements. A function call with five unexplained parameters just is that useful to me. Does anyone have or know of a resource that can help me figure out how to get started?
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709
Feb ’25
IOUSBHostInterface::Open for interrupt interfaces works on iPad Air but not iPad Pro
I am trying to open the CommunicationControl class IOUSBHostInterface in my USB driver, but it only seems to open on iPad Airs and not iPad Pros. I'm calling ivars->interruptInterface->Open(this, 0, NULL); After retrieving the interruptInterface from the device's InterfaceIterator. I try and open this, but on iPad Pros it returns kIOReturnNotOpen. I've tried closing and reopening the IOUSBHostDevice, closing and reopening the Interface, AbortDeviceRequests before opening, etc. but it just seems to work on iPad Air and not iPad Pro. I've tried on both iPadOS 17.6.1 and 18.2 Has anyone else seen this?
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638
Dec ’24
NSInternalInconsistencyException Call must be made on main thread
#4 Thread NSInternalInconsistencyException Call must be made on main thread CoreFoundation ___exceptionPreprocess + 164 libsystem_pthread.dylib _start_wqthread + 8 #0 Thread semaphore_wait_trap libsystem_kernel.dylib semaphore_wait_trap + 8 libdispatch.dylib 0x00000001b96ed000 + 457547470247841612 UnityFramework Staticburst_initialize + 17597401577822386088 UnityFramework DllCanUnloadNow + 52172 UnityFramework. DllCanUnloadNow + 51292 UnityFramework DllCanUnloadNow + 421068 UnityFramework. Unityplcrash_async_mach_exception_get_siginfo + 5073080 UnityFramework. GlobalizationNative_GetTimeZoneDisplayName + 1585284 UnityFramework. GlobalizationNative_GetTimeZoneDisplayName + 926212 UnityFramework. 0x000000010ce18000 + 77478852 UnityFramework. GlobalizationNative_GetTimeZoneDisplayName + 124804 UnityFramework. GlobalizationNative_GetTimeZoneDisplayName + 124592 UnityFramework. _ZdaPvRKSt9nothrow_t + 2445400 UnityFramework. _ZdaPvRKSt9nothrow_t + 2502608 UnityFramework. _ZdaPvRKSt9nothrow_t + 2556896 UnityFramework. _ZdaPvRKSt9nothrow_t + 2555820 UnityFramework. _ZdaPvRKSt9nothrow_t + 211836 UnityFramework. _ZdaPvRKSt9nothrow_t + 1216980 UnityFramework. _ZdaPvRKSt9nothrow_t + 1145620 UnityFramework. _ZdaPvRKSt9nothrow_t + 1145684 UnityFramework. _ZdaPvRKSt9nothrow_t + 1146408 UnityFramework. UnitySendMessage + 6940844 UnityFramework. _Z12DecodeBase64PKhPhi + 138076 QuartzCore. 0x00000001b2d06000 + 193228 UIKitCore. UIApplicationMain + 1589427071078105428 UnityFramework. _Z12DecodeBase64PKhPhi + 11056988545834161928
1
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586
Dec ’24
Crash in IOService::Create
I am getting an unexpected crash from IOService::Create() when attempting to create a new user-client. The crash is a nullptr exception in OSCopyInObjects(). The last call from my code was IOService::Create(). As far as I can tell, all the input parameters to Create() are correct, and the Info.plist is has the correct key and class information - indeed, if I corrupt these I get an error status return rather than a crash. Any suggestions as to what could be causing this? I suspect that the problem may be related from a change in the underlying application that is creating the user client. This was modified from a standard app to a daemon, following the advice here: https://developer.apple.com/documentation/xcode/signing-a-daemon-with-a-restricted-entitlement. However, it is the driver that crashes - not the host opening the user client.
1
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503
Jan ’25
No logs from log stream | grep CompanyName
I have USB DriverKit driver. When I use the log command below to get log, there is logs from my driver on my own M-series MacBook where the driver is built using developer account. log stream | grep CompanyName But on other mac like (M-series) Mac Mini, there is no log captured from driver though the driver is communicating with the machine correctly. The only log captured are from MacOS regarding CompanyName driver status/unload/load. The MacOS is Sonoma 14.7.2 and 14.7.3. Please advise on how to get log from driver since writing to files is not allowed in DriverKit. I need logs to troubleshoot on Mac Mini. Thanks.
1
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480
Feb ’25
DriverKit IOUSBHostInterface iterator always empty
I'm trying to iterate through a USB device but the iterator is always empty or contains only the matched interface: Single interface in Iterator This happens when my driver matches against the interface. Because I need to use 2 interfaces (control and cdc), I try to open the IOUSBHostDevice (copied from the interface) and iterate through the rest, but I only get the interface my dext matched with. Empty Iterator I decided to match against USB communication devices, thinking things would be different. However, this time the interface iterator is completely empty (provider is IOUSBHostDevice). Here's a snippet of my code before iterating with IOUSBHostDevice->CopyInterface(): // teardown the configured interfaces. result = device->SetConfiguration(ivars->Config, true); __Require_noErr_Action(result, _failure_Out, ELOG("IOUSBHostDevice::SetConfiguration failed 0x%x", result)); // open usb device result = device->Open(this, 0, 0); __Require_noErr_Action(result, _failure_Out, ELOG("Failed to open IOUSBHostDevice")); // Get interface iterator result = device->CreateInterfaceIterator(&iterRef); __Require_noErr_Action(result, _failure_Out, ELOG("IOUSBHostDevice::CreateInterfaceIterator failed failed: 0x%x", result));
1
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264
Mar ’25
Why UserInitializeTargetForID() not be invoked after UserCreateTargetForID() successfully?
Hello Everyone, I am trying to create a Fake SCSI target based on SCSIControllerDriverKit.framework and inherent from IOUserSCSIParallelInterfaceController, here is the code kern_return_t IMPL(DRV_MAIN_CLASS_NAME, Start) { ... // Programmatically create a null SCSI Target SCSIDeviceIdentifier nullTargetID = 0; // Example target ID, adjust as needed ret = UserCreateTargetForID(nullTargetID, nullptr); if (ret != kIOReturnSuccess) { Log("Failed to create Null SCSI Target for ID %llu", nullTargetID); return ret; } ... } According the document UserCreateTargetForID, after creating a TargetID successfully, the framework will call the UserInitializeTargetForID() The document said: As part of the UserCreateTargetForID call, the kernel calls several APIs like UserInitializeTargetForID which run on the default dispatch queue of the dext. But after UserCreateTargetForID created, why the UserInitializeTargetForID() not be invoked automatically? Here is the part of log show init() - Start init() - End Start() - Start Start() - try 1 times UserCreateTargetForID() - Start Allocating resources for Target ID 0 UserCreateTargetForID() - End Start() - Finished. UserInitializeController() - Start - PCI vendorID: 0x14d6, deviceID: 0x626f. - BAR0: 0x1, BAR1: 0x200004. - GetBARInfo() - BAR1 - MemoryIndex: 0, Size: 262144, Type: 0. UserInitializeController() - End UserStartController() - Start - msiInterruptIndex : 0x00000000 - interruptType info is 0x00010000 - PCI Dext interrupt final value, return status info is 0x00000000 UserStartController() - End Any assistance would be greatly appreciated! Thank you in advance for your support. Best regards, Charles
1
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363
Mar ’25