You might want to add the following udev rule under /etc/udev/rules.d:

ATTRS{idVendor}=="03eb", ATTRS{idProduct}=="2ff4", MODE="0664", GROUP="plugdev"

so when you plug the Atmel chip to program, the device becomes
available to all the members of the "plugdev" group.

You will need to reboot your system or run the following command:

sudo udevadm control --reload