I recently got a kindle fire for testing, but had some issues connecting it to ADB.

• Get the Vendor id by typing:
  

  lsusb 

  The line we are looking for is:
  Bus 003 Device 026: ID 1949:0006 Lab126
• Add the vendor id (1949) to /etc/udev/rules.d/51-android.rules as per normal

  SUBSYSTEM=="usb", SYSFS{idVendor}=="1949", MODE="0666"

  Usually a device would work here but it wasnt happening with the fire …
• The solution is as per this link: StackOverflow
  You also need to add the vendor id to ~/.android/adb_usb.ini (you need to check the file doesn’t exist first).
  

  echo "0x1949" >>~/.android/adb_usb.ini
  echo "0x0006" >>~/.android/adb_usb.ini

• Then we restart the ADB server and the device should be shown:

  adb kill-server
  adb start-server
  adb devices