hid_device_info->interface_number zero on macOS 13.3

[dingsijie-nreal]

I've noticed comment here: https://github.com/libusb/hidapi/blob/master/mac/hid.c#L543
The interesting thing is: macOS Monterey(12.6.3) works perfectly with my usb gadget, I got expected interface numbers.
the output of test.c is shown below:

hidapi test/example tool. Compiled with hidapi version 0.14.0, runtime ve
Compile-time version matches runtime version of hidapi.

Device Found
  type: 3318 0424
  path: DevSrvsID:4298350859
  serial_number: A00016:33:33
  Manufacturer: xxxx
  Product:    xxxx
  Release:      1
  Interface:    3
  Usage (page): 0x0 (0x41)
  Bus type: 1

  Report Descriptor: (27 bytes)
0x05, 0x41, 0x09, 0x00, 0xa1, 0x01, 0x15, 0x00, 0x25, 0xff, 
0x19, 0x01, 0x29, 0x08, 0x95, 0x40, 0x75, 0x08, 0x81, 0x02, 
0x19, 0x01, 0x29, 0x08, 0x91, 0x02, 0xc0, 
Device Found
  type: 3318 0424
  path: DevSrvsID:4298350872
  serial_number: A00016:33:33
  Manufacturer: xxxx
  Product:      xxxxx
  Release:      1
  Interface:    5
  Usage (page): 0x0 (0x41)
  Bus type: 1

  Report Descriptor: (27 bytes)
0x05, 0x41, 0x09, 0x00, 0xa1, 0x01, 0x15, 0x00, 0x25, 0xff, 
0x19, 0x01, 0x29, 0x08, 0x95, 0x40, 0x75, 0x08, 0x81, 0x02, 
0x19, 0x01, 0x29, 0x08, 0x91, 0x02, 0xc0, 
Device Found
  type: 3318 0424
  path: DevSrvsID:4298350862
  serial_number: A00016:33:33
  Manufacturer: xxxx
  Product:      xxxxx
  Release:      1
  Interface:    4
  Usage (page): 0x0 (0x41)
  Bus type: 1

  Report Descriptor: (27 bytes)
0x05, 0x41, 0x09, 0x00, 0xa1, 0x01, 0x15, 0x00, 0x25, 0xff, 
0x19, 0x01, 0x29, 0x08, 0x95, 0x40, 0x75, 0x08, 0x81, 0x02, 
0x19, 0x01, 0x29, 0x08, 0x91, 0x02, 0xc0, 

But, after upgrading to macOS 13.3 the result changes to flowing:

hidapi test/example tool. Compiled with hidapi version 0.14.0, runtime version 0.14.0.
Compile-time version matches runtime version of hidapi.

Device Found
  type: 3318 0424
  path: DevSrvsID:4294984005
  serial_number: A00016:33:33
  Manufacturer: xxxxx
  Product:      xxxxx
  Release:      1
  Interface:    0
  Usage (page): 0x0 (0x41)
  Bus type: 1

  Report Descriptor: (27 bytes)
0x05, 0x41, 0x09, 0x00, 0xa1, 0x01, 0x15, 0x00, 0x25, 0xff, 
0x19, 0x01, 0x29, 0x08, 0x95, 0x40, 0x75, 0x08, 0x81, 0x02, 
0x19, 0x01, 0x29, 0x08, 0x91, 0x02, 0xc0, 
Device Found
  type: 3318 0424
  path: DevSrvsID:4294984010
  serial_number: A00016:33:33
  Manufacturer: xxxxx
  Product:      xxxxx
  Release:      1
  Interface:    0
  Usage (page): 0x0 (0x41)
  Bus type: 1

  Report Descriptor: (27 bytes)
0x05, 0x41, 0x09, 0x00, 0xa1, 0x01, 0x15, 0x00, 0x25, 0xff, 
0x19, 0x01, 0x29, 0x08, 0x95, 0x40, 0x75, 0x08, 0x81, 0x02, 
0x19, 0x01, 0x29, 0x08, 0x91, 0x02, 0xc0, 
Device Found
  type: 3318 0424
  path: DevSrvsID:4294984008
  serial_number: A00016:33:33
  Manufacturer: xxxxx
  Product:      xxxxx
  Release:      1
  Interface:    0
  Usage (page): 0x0 (0x41)
  Bus type: 1

  Report Descriptor: (27 bytes)
0x05, 0x41, 0x09, 0x00, 0xa1, 0x01, 0x15, 0x00, 0x25, 0xff, 
0x19, 0x01, 0x29, 0x08, 0x95, 0x40, 0x75, 0x08, 0x81, 0x02, 
0x19, 0x01, 0x29, 0x08, 0x91, 0x02, 0xc0, 

My mission it to discriminate 3 different components on my USB gadget, and the interface number was the key that I rely on.
But with 0 interfaces numbers, I don't know how to do my job.
Any one get any ideas? Thanks a lot.

[Youw]

Would you be able to modify HIDAPI locally and print all dev properties (key/values)?

[dingsijie-nreal]

Yes, I can. And I think all items in hid_api_info struct (https://github.com/libusb/hidapi/blob/master/hidapi/hidapi.h#L150)
already printed out.
What other info shall I try to print?

[Youw]

I meant printing all properties available via IOHIDDeviceGetProperty.
But I just briefly checked the API - it doesn't seem like there is a list of all available keys...

[dingsijie-nreal]

Well, I noticed this PR #530
It was submitted by one of my coworkers.
The PR is a workaround we found.
For now I think

hidapi/mac/hid.c

Line 550 in 9f185ec

cur_dev->interface_number = get_int_property(dev, CFSTR(kUSBInterfaceNumber));

is the
only "proper" way to get the interface number. But it just doesn't work on the latest macOS.
We've posted a question at https://developer.apple.com/forums/thread/728001.
No one replys... Maybe you can also have a look at the post, and say something there.

[Youw]

there is always a solution to find a corresponding USB/device interface having the Location ID - that one is guaranteed to match

that would be lesser workaround

[mcuee]

I have created an issue based on this discussion. I can reproduce the issue under macOS 13.3.1 on my Mac Mini M1. From my test, libusb works fine to find the interface number. Maybe we can take some reference from libusb code.

• hid_device_info->interface_number zero on macOS 13.3 #531

[pengxianheng-nreal]

@mcuee I has tested by using libusb at first。 It really find non-zero interface number 。 but it needs to input 'sudo' to run an bin file or libusb_detach_kernel_driver will failed!

[mcuee]

Yes, that is correct. libusb is not a suitable library for HID device under macOS. In fact libusb project recommends using HIDAPI for HID device.

However, I am thinking that the following code snipets may be able to help to sort this issue out under macOS. I believe these lines of codes do not need sudo. sudo is only needed when you are carrrying out real USB transfers with the device, not for enumeration.
https://github.com/libusb/libusb/blob/master/libusb/os/darwin_usb.c#L1342-L1377

Same comments here.
#531 (comment)

[Youw]

This is more a bug report than a discussion in a first place.
Closing in favor of #531.