We’re looking for a reliable way to determine whether an iPad device supports DriverKit. Since there doesn't appear to be a direct public API for this, our current approach is as follows: Retrieve the device’s model identifier (e.g., "iPad14,8") and the iOS/iPadOS version. Map the model identifier to a known iPad model and its associated chip. If the device has an M-series chip, we assume it supports DriverKit. For future-proofing, we plan to assume that any future iPad with a model identifier of iPad15,* or higher will contain an M-series chip and therefore support DriverKit. We have a couple of questions: Is there a more reliable or official API to determine the chip version or DriverKit support? Is it reasonable to rely on the assumptions outlined in steps 2 and 3 for determining DriverKit compatibility?

Hi, our CoreAudio server plugin supports different clock sources. A switch might result in a change of the selectable sample rates (and other settings). On a clock source switch the plugin reconfigures the set of available kAudioStreamPropertyAvailablePhysicalFormats and announces the change via AudioServerPlugInHostInterface::PropertiesChanged(). However at least the Audio MIDI Setup seems to ignore to update it's UI. The changes are first reflected after selecting another device and re-selecting the device of interest. (Latest macOS, M4 macMini) Is this a bug? Or is our CoreAudio server plugin required to indicate the change in the list of available audio formats differently? Thanks!

Hello everyone. I have been developing PCIe device driver through Thunderbolt. However, it was confirmed that up to three devices connected to the daisy chain worked normally, but the fourth device failed to operate the _CopyDeviceMemoryWithIndex() function for connection with the BAR0 App and did not work properly. The standard specification of Thunderbolt 3/4 is said to be supported by daisy chain connection up to 6-device, but in reality, it is only 3 units, so I ask the forum for technical confirmation. Of course total 4 device by 2-port x 2-device daisy chain connecting has working well. The PCI entry in System information indicates that all devices have normal load of the PCIe device driver. Thank you.

Hello everyone I have been developing PCIe device driver through Thunderbolt. However, it was confirmed that up to three devices connected to the daisy chain worked normally, but the fourth device failed to operate the _CopyDeviceMemoryWithIndex() function for connection with the BAR0 App and did not work properly. The standard specification of Thunderbolt 3/4 is said to be supported by daisy chain connection up to 6 units, but in reality, it is only 3 units, so I ask the forum for technical confirmation. Of course total 4 device by 2-port x 2-device daisy chain connecting has working well. And the PCI entry in System information app indicates that all devices have normal load of the PCIe device driver.

Since updating to iOS18.4.1, I can no longer remove Waze from operating in Carplay. It was working perfectly prior to this update where I could view the Waze map on my iPhone 12 Pro, rather than the Carplay map. I prefer to use my iPhone map rather than the Carplay map. Now as soon as I open Waze, despite my having customized and removing it from the Carplay list, while the icon is removed, it continues to open in Carplay! Help! I cannot use Waze using the Carplay maps! Anyone have a solution?

Hi, our virtual CoreAudio server plugin creates and removes dynamically CoreAudio devices. Each time it does so it leaves traces in /Library/Preferences/Audio com.apple.audio.DeviceSettings.plist com.apple.audio.SystemSettings.plist The files on the test machine now have become >1Mb and the system keeps recreating them. How can I manually remove/cleanup these files? (This is for development only. It already became pretty tedious to evaluate current device settings for debugging purposes.) How can the CoreAudio server plugin make sure once a device has been removed also its entries are removed from the .plist (It already removes it's storage, but the system still keeps other settings.) Is there some documentation about what gets stored and how the settings are organized in these preferences? (This is also for development and debugging only. We are not intending to access these settings directly ) Thanks!

Hello, I recently created an app with the Calldirectory Extension. It worked all good as long as I was on my development iphone. I tried to install the app on my privat iphone (same phone/same os version), but then I faced an issue. I couldn't enable the Calldirectory Extension with an error (Error Enabling Extension Failed to request data for APPNAME. You may try enabling the extension again, and if the problem persists, conatact the application developer.)

Hi Everyone! I want to block the USB wired mouse from accessing my machine. Which framework is used to implement ? PS: I have already tried DriverKit Framework but it requires Apple's paid developer account. What will be alternative ?

When I develop the system extension tool, I need to subscribe to the remote thread creation event. When the remote thread injection is triggered, I want to get the id, module name and starting function name of the remote thread. How can I get this information from es_event_remote_thread_create_t? If I can't get this information from es_event_remote_thread_create_t, is there any other way to get it?

I have a custom USB Audio Class 2 (UAC2) compatible device. When I connect this custom device to a MacBook with a configuration of up to 10 channels (16-bit), everything seems to work fine. However, when I increase the channel count to 12, the MacBook does not recognize the 12 channels. It only shows the channel count as 0. TN2274 is the only source where I found some information about Apple's Audio Class Drivers, but it doesn't mention any limitations regarding channel counts. Could you let me know the current limitations of the Audio Class Drivers on the latest macOS versions? What configuration should I use to get 12 channels working? P.S. I also found that a 12-channel, 8-bit configuration is detected by the MacBook, bit I want it to work with 16bits. For more detail please check FB17098863

Hello everyone, I’m working on implementing hardware interrupt handling in DriverKit and came across the InterruptOccurred method in IOInterruptDispatchSource. I noticed that its declaration ends with a TYPE macro: virtual void InterruptOccurred(OSAction* action, uint64_t count, uint64_t time) TYPE(IOInterruptDispatchSource::InterruptOccurred); This structure seems similar to how Timer Events are set up, where an event is linked to a callback and triggered by a timer. I’m attempting to use a similar approach, but for hardware-triggered interrupts rather than timer events. I’m currently in the trial-and-error phase of the implementation, but if anyone has a working example or reference on how to properly implement and register InterruptOccurred, it would be greatly appreciated! Best regards, Charles

Hi Apple support, We requested the 4 HID-related Entitlements back in December 2024. Similarly to another post here in the forums that was completely ignored, our request has NOT been processed for months. Mailing the support staff results in boilerplate email responses with no content, calling them results in a chat with very nice people who are unable to help since they can't seem to reach the entitlement team directly. Having to wait for MONTHS when dealing with one of the biggest and supposedly best companies in the world is beyond disappointing. Can anyone help? Is there anyone else that has had this same issue and that has found a work-around? I can share all necessary details. Thanks, Matteo

I’m experiencing a persistent issue with the new USB-C lossless audio feature on AirPods Max (firmware 7E101). I’m using original Apple USB-C to USB-C cable and have tested this setup across multiple Apple devices, including: • iPhone (running iOS 18.5 beta) • iPad Pro with USB-C • MacBook Pro (15.5 Beta) ❗️Problem: Despite Apple’s announcement that AirPods Max now support wired lossless audio over USB-C, I’m unable to get any audio output via USB-C on any device. • On iPhone: I disabled Bluetooth, connected via USB-C — no sound. • On MacBook: The device is shown as “AirPods Max USB Audio” in System Information > USB, but it does not appear in Sound settings or Audio MIDI Setup as an available output. • On iPad Pro: Same behavior — no audio output. Other details: • I performed a factory reset of the headphones, but the LED flashes red instead of the expected amber → white sequence. (Apple’s documentation does not mention red flash behavior during reset — might indicate an error state.) • The issue is not isolated to the iOS 18.5 beta — since the same behavior occurs on macOS and iPadOS. What works: • Bluetooth audio still works fine. • The cable and USB-C ports function with other audio devices. ⸻ Summary: It looks like: • USB audio is being detected on a hardware level (at least on Mac), • but software support for output (especially on macOS/iPadOS) is either not implemented, disabled, or bugged — possibly connected to iOS 18.5 beta or broader OS-level limitations.

Hi, trying to upgrade from macOS Sequoia 15.3.2 to 15.4 gives this error. Now I can not boot from internal drive of M1 Air 2020, because it restores 15.4, that does not boot. I can only boot from external USB SSD that has macOS 15.3.2. How I can install back 15.3.2 or alternatively newer macOS to internal drive? I only have one Mac, this M1 Air 2020. I have AppleAppleCare+ to 9/18/25. Remaining of error is attached here: Can't ignore lock validation @t8020dart.c:535 panic(cpu 2 caller 0x0): t8020dart 0xfffffdf053908000 (dart-dispext0): Can't ignore lock validation @t8020dart.c:535 Debugger message: panic Memory ID: 0x6 OS release type: Not set yet OS version: Not set yet Kernel version: Darwin Kernel Version 24.4.0: Wed Mar 19 21:12:54 PDT 2025; root:xnu-11417.101.15~1/RELEASE_ARM64_T8103 Fileset Kernelcache UUID: 2BBA525B95E0E6B962ECC44FC093AB57 Kernel UUID: 4E6CBD31-CD1E-3939-8A63-211A206AFA66 Boot session UUID: 3A34167D-2534-402F-9679-2CAD45F67CDA iBoot version: iBoot-11881.101.1 iBoot Stage 2 version: iBoot-11881.101.1 secure boot?: YES

Hello Everyone, I'm encountering an issue while setting up a timer event in DriverKit and would appreciate any guidance. Here's my current implementation: void DRV_MAIN_CLASS_NAME::SetupEventTimer() { // 1. Create dispatch queue kern_return_t ret = IODispatchQueue::Create("TimerQueue", 0, 0, &ivars->dispatchQueue); if (ret != kIOReturnSuccess) { LogErr("Failed to create dispatch queue: 0x%x", ret); return; } // 2. Create timer source ret = IOTimerDispatchSource::Create(ivars->dispatchQueue, &ivars->dispatchSource); if (ret != kIOReturnSuccess) { LogErr("Failed to create timer: 0x%x", ret); OSSafeReleaseNULL(ivars->dispatchQueue); return; } /*! * @brief Create an instance of OSAction. * @discussion Methods to allocate an OSAction instance are generated for each method defined in a class with * a TYPE attribute, so there should not be any need to directly call OSAction::Create(). * @param target OSObject to receive the callback. This object will be retained until the OSAction is * canceled or freed. * @param targetmsgid Generated message ID for the target method. * @param msgid Generated message ID for the method invoked by the receiver of the OSAction * to generate the callback. * @param referenceSize Size of additional state structure available to the creator of the OSAction * with GetReference. * @param action Created OSAction with +1 retain count to be released by the caller. * @return kIOReturnSuccess on success. See IOReturn.h for error codes. */ // 3: Create an OSAction for the TimerOccurred method // THIS IS WHERE I NEED HELP OSAction* timerAction = nullptr; ret = OSAction::Create(this, 0, 0, 0, &timerAction); if (ret != kIOReturnSuccess) { LogErr("Failed to create OSAction: 0x%x", ret); goto cleanup; } // 4. Set handler ret = ivars->dispatchSource->SetHandler(timerAction); if (ret != kIOReturnSuccess) { LogErr("Failed to set handler: 0x%x", ret); goto cleanup; } // 5. Schedule timer (1 second) uint64_t deadline = mach_absolute_time() + NSEC_PER_SEC; ivars->dispatchSource->WakeAtTime(0, deadline, 0); cleanup: if (ret != kIOReturnSuccess) { OSSafeReleaseNULL(timerAction); OSSafeReleaseNULL(ivars->dispatchSource); OSSafeReleaseNULL(ivars->dispatchQueue); } } Problem: The code runs but the OSAction callback binding seems incorrect (Step 3). According to the OSAction documentation, I need to use the TYPE macro to properly bind the callback method. But I try to use TYPE(DRV_MAIN_CLASS_NAME::TimerOccurred) kern_return_t TimerOccurred() LOCALONLY; TYPE(TimerOccurred) kern_return_t TimerOccurred() LOCALONLY; kern_return_t TimerOccurred() TYPE(DRV_MAIN_CLASS_NAME::TimerOccurred) LOCALONLY; All results in Out-of-line definition of 'TimerOccurred' does not match any declaration in 'DRV_MAIN_CLASS_NAME' Questions: What is the correct way to declare a timer callback method using TYPE? How to get the values targetmsgid & msgid generated by Xcode? Any help would be greatly appreciated! Best Regards, Charles

Hello Everyone, I encountered an issue with PCI memory access in DriverKit. In my case, BAR0 is not available, but BAR1 is ready for use. Here’s the log output: !!! ERROR : Failed to get BAR0 info (error: 0xe00002f0). !!! BAR1 - MemoryIndex: 0x00000000, Size: 0x00040000, Type: 0 Issue Description When I initially wrote to BAR0 using memoryIndex = 0, it worked successfully: AME_Address_Write_32(pAMEData, pAMEData->memoryIndex, AME_HOST_INT_MASK_REGISTER, 0x0F); However, I mistakenly forgot to update memoryIndex to 1 for BAR1. Surprisingly, the write operation still succeeded. When I fixed memoryIndex = 1 for BAR1, the write operation no longer had any effect. There was no error, but the expected behavior did not occur. Relevant API (From IOPCIDevice.iig) /*! /*! * @brief Writes a 32-bit value to the PCI device's aperture at a given memory index. * @discussion This method writes a 32-bit register on the device and returns its value. * @param memoryIndex An index into the array of ranges assigned to the device. * @param offset An offset into the device's memory specified by the index. * @param data A 32-bit value to be written in host byte order. */ void MemoryWrite32(uint8_t memoryIndex, uint64_t offset, uint32_t data) LOCALONLY; Log Output: Writes to BAR0 (memoryIndex = 0) AME_Address_Write_32() called memoryIndex: 0, offset: 0x34, data: 0xf Wrote data 0xF to offset 52 AME_Address_Write_32() called memoryIndex: 0, offset: 0xa0, data: 0x1 Wrote data 0x1 to offset 160 AME_Address_Write_32() called memoryIndex: 0, offset: 0x20, data: 0xffffffff Wrote data 0xFFFFFFFF to offset 32 Writes to BAR1 (memoryIndex = 1) – No Response AME_Address_Write_32() called memoryIndex: 1, offset: 0x34, data: 0xf No confirmation log, no visible effect. Questions What should memoryIndex be set to for BAR1? The log shows "BAR1 - MemoryIndex: 0x00000000", but should I be using 1 instead? How can I verify if a write operation to BAR1 is successful? Is there a way to check if the memory region is actually writable? Should I use MemoryRead32() to confirm the written value? Any guidance would be greatly appreciated! Best Regards, Charles

We have a macOS application which interacts with our USB and PCI devices to perform SCSI and NVME commands on them. We use IOUSBHost, IOUSBLib and IOKitLib for USB interface and have created a custom driver to interact with PCI devices. Is there a way we can implement a similar functionality for iOS as well if we connect the cards and readers using OTG?

When plugging in my matched USB device I see the logs below. It seems the kernelmanagerd process is sandboxed and can't write out the reason my Dext failed to load. Is there somewhere else I can look for this info? default 11:03:22.175152-0700 kernelmanagerd Received kext load notification: me.keithg.MyUserUSBInterfaceDriver default 11:03:22.177637-0700 kernel 1 duplicate report for Sandbox: icdd(2124) allow file-read-data /Library/Image Capture/Devices error 11:03:22.177681-0700 kernel Sandbox: kernelmanagerd(545) deny(1) file-write-create /private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/com.apple.kernelmanagerd/TemporaryItems com.apple.libcoreservices error 11:03:22.177711-0700 kernelmanagerd mkdir: path=/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/com.apple.kernelmanagerd/TemporaryItems/ mode= -rwx------: [1: Operation not permitted] error 11:03:22.179361-0700 kernel Sandbox: kernelmanagerd(545) deny(1) file-write-create /private/var/db/loadedkextmt.plist.sb-5a00fc77-LNttZF com.apple.libcoreservices error 11:03:22.177755-0700 kernelmanagerd _dirhelper_relative_internal: error for path <private>: [1: Operation not permitted] com.apple.accessories default 11:03:22.177674-0700 WindowServer Sending analytics event... (eventName: com.apple.ioport.transport.USB.published) error 11:03:22.179913-0700 kernelmanagerd Failed to write extension load report plist.

When my virtual CoreAudio server plugins propagates a change to it´s device name the CoreAudio system does not seem to reflect the change. My user mode application subscribes to the property change and receives the change though. I also alternatively submitted a kAudioObjectPropertyName change with the same effect. Is this possible at all and what needs to be done then? Are there restrictions about which properties can be successfully changed and are reflected by the system? Any hint is highly appreciated! Thanks

I'm working on a project to allow HID input from macOS to a connected iOS device. Are we prohibited from matching to a connected iPhone with DriverKit? I see the attribute kCDCDoNotMatchThisDevice for my iPhone is YES when looking at the IO registry and my dext does not initialize