So this is definitely a bug with ModemManager as far as I can tell. I disabled the service completely by running:
sudo systemctl mask ModemManager.service Rebooted and my device works perfectly. It stays as the expected /dev/ttyACM0 device even after it resets itself and I don't see any hanging references to the old /dev/ttyACM* devices. Not sure what changed in ModemManager but it's definitely causing a problem for some devices. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1473246 Title: MediaTek Preloader on a mobile device triggers cdc_acm kernel module usage by ModemManager To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/modemmanager/+bug/1473246/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
