It turns out that the problem is an incompatibility with the packages network-manager + network-manage-gnome
Whenever these are installed, usbserial becomes intransparent (i.e., physical and logical devices are present, but there is no thoughput through the serial interface). After removal of these packages and after system restart the serial interface works as it should. Maybe this should be considered a bug of one of these packages. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/700316 Title: usbserial stopped working during a recent upgrade, no serial line via usb anymore -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
