[howto] Get CEC working with Kodi on a Vizio TV ( P55 )

 Original solution from her: https://forum.kodi.tv/showthread.php?tid=352993

1. SSH into kodi, usually root and libreelec ( should change this asap)
2. Stop Kodi via the GUI or terminal with "systemctl stop kodi". 
3. Edit the CEC Adapter config file in "/storage/.kodi/userdata/peripheral_data/ via the terminal". This configuration file name varies based on the adapter. For example, for RPI, it seems to be "rpi_2708_1001.xml", and for a Pulse Eight CEC-Adapter, it seems to be "usb_2548_1002_CEC_Adapter.xml". 
4. Change line "device_type = 1" to "device_type = 4". This will force the adapter to register as a Playback device rather than a Recording device.
5. Restart Kodi by restarting the machine or running "systemctl start kodi" in the terminal.
6. May need to restart TV or go into CEC settings and Discover 

Edit: The most important part got left out.