Unable to communicate with certain USB devices

[sarietta]

I believe there is a bug in aotg that prevents communication to certain USB devices. I have not yet been able to pin down exactly what the issue is, but I seem unable to read (i.e. get data from the input endpoint) from some USB devices.

According to Wireshark, the only immediate thing that seems like a potential issue is that some USB devices return ENOENT when performing a USB interrupt on the input endpoint, which may be misinterpreted as an actual error. In fact, this is not supposed to be considered an error according to: https://books.google.com/books?id=M7RHMACEkg4C&pg=PT373&lpg=PT373&dq=enoent+usb_submit_urb&source=bl&ots=s2K2McgPWz&sig=MmxCUR_gpkvSBPQ7J1x8FDT7oEQ&hl=en&sa=X&ved=0ahUKEwit4MLO5aHPAhUW9mMKHWd6D04Q6AEIKTAC#v=onepage&q=enoent%20usb_submit_urb&f=false

I have verified that the device in question does return an ENOENT, but when I analyze the communication between that device and another machine, the other machine still returns the extra data in the URB, while the Lemaker Guiter does not.

Anyone able to provide more clarity on where this issue may be coming from?