Title: udev rule to identify specific device Subject:

#------------------------------------------------------------------------------
# Identify the device when you plug it in
#------------------------------------------------------------------------------
sudo udevadm monitor

# Plug in the device, and note the output.

Ctrl-c

#------------------------------------------------------------------------------
# List the udev device, and get the vendor and product id
#------------------------------------------------------------------------------
lsusb -v

#------------------------------------------------------------------------------
# Make a udev rule for this device,
# such that it creates a link when this device is found
#------------------------------------------------------------------------------
sudo cat > /etc/udev/rules.d/51-at91sam_cdc_acm.rules << 'EOF'
#
# Create symlink to what ever usb device matches our target
#
#ACTION=="add", SUBSYSTEM=="usb", ATTR{idProduct}=="6124", ATTR{isdVendor}=="03eb", RUN+="/usr/bin/logger 'Found sam-ba'"
#ACTION=="add", SUBSYSTEMS=="usb", ATTRS{idProduct}=="6124", ATTRS{idVendor}=="03eb", MODE="0600", GROUP="steveg"
KERNEL=="ttyACM*", ATTRS{idProduct}=="6124", ATTRS{idVendor}=="03eb", SYMLINK+="ttyUSB-AT91SAMBA%n", ENV{ID_MM_DEVICE_IGNORE}="1"
EOF

#------------------------------------------------------------------------------
# reload udev rules
#------------------------------------------------------------------------------
sudo udevadm control --reload-rules
sudo udevadm monitor 

#------------------------------------------------------------------------------
# replug the device and watch
#------------------------------------------------------------------------------

#------------------------------------------------------------------------------
# Make script to tell you which device the link points to
#------------------------------------------------------------------------------
echo > find_my_device.bash <<'EOF'

echo "Determine where the link points..."

serial_interface="/dev/ttyUSB-AT91SAMBA0"

# Check if link exists, set by udev rule.
if [[ -h "${serial_interface}" ]]; then
  serial_port="/dev/$(readlink ${serial_interface})"
  echo "Found serial device for AT91SAMBA: ${serial_interface}"
else
  echo "Link not found."
  exit 1
fi

# Check if link points to valid serial device file
if [[ -c "${serial_port}" ]]; then
  echo "Driver linked to serial port: ${serial_port}"
else
  echo "Driver not linked to vaild serial port: ${serial_port}"
  echo "Exiting!"
  exit 1
fi
EOF