We have a fx1 device that works perfectly in Windows. However, we've been told that is goes to default USB Device behaviour when used on Linux environment. I mean the device replies with an eeprom vid/pid (0xc0 load) handling the GET_DEVICE_DESCRIPTOR request. It also replies with zero-length vendor request control endpoint transfers (resulting in -71 protocol errors on Linux). I guess it's Default USB Device working (ezusb core).
So here's my question. What are the possible methods of going back to default usb device from a user firmware running mode? Can you list them all (electrical/programmatic) so I could check & debug 'em one by one?
p.s. The device is bus-powered. There was no physical disconnection, of course.
Are you trying to query the device descriptor using a Vendor driver – or does he want to make it enumerate with Bootcode – i.e default VID/PID?
Please let us know.