On Fri, 2019-09-27 at 19:38 +0200, Greg KH wrote:
> What does the usb descriptors for the device look like?  Is it only
> the
> "default" control endpoint and no interfaces?  What does the output
> of
> 'usbdevices' show for the device?

The device in question can be an iPhone, an iPod Classic/Nano, or an
iPad, amongst others, and they usually have useful interfaces, such as
mass storage for the older ones, or ethernet, PTP, etc.

> Normally you just bind to the "default" interface for the device, and
> all is good, there should be a few other drivers in the tree that do
> this, but I can't think of one off the top of my head at the moment.

All the interfaces (in the different configurations) are used for
something in the case of the iPhone 6S I'm trying to use.

I've attached the output of "lsusb -v" for the device below.