I see the following when I fire up the Arduino IDE:
Picked up JAVA_TOOL_OPTIONS: -Dgnu.io.rxtx.SerialPorts=/dev/tty96B0
Gtk-Message: Failed to load module "pk-gtk-module"
Gtk-Message: Failed to load module "canberra-gtk-module"
Basically the default image is shipping with an environment variable set to allow the IDE to work with the 96boards-sensors mezzanine… and it looks like this is disrupting usage with real Arduino boards.
I’m afraid I don’t have an Uno to test with, but perhaps try one of the following options from a terminal emulator.
Removing the special configuration option:
linaro-alip$ unset JAVA_TOOL_OPTIONS
Overriding the special configuration option:
linaro-alip$ JAVA_TOOL_OPTIONS=-Dgnu.io.rxtx.SerialPorts=/dev/ttyACM0 arduino