First, thank you all for your answers.
@knc1 : I look into making a cable myself. I'll look for new material.
@geekmaster : Well, I made the list of everything I had in /dev/disk/by id, uuid, path and label and linked every single device to something different that the kindle.
After your question, I looked a bit deeper and found this in the dmseg :
[105628.104580] scsi 14:0:0:0: Direct-Access Kindle Internal Storage 0100 PQ: 0 ANSI: 2
[105628.145553] sd 14:0:0:0: [sdd] Attached SCSI removable disk
There is a /dev/sdd, but no partition on it.
@hawhill : I have tried over and over, maniacally the 15s,20s ... 1 min technique
The fact is that the picture on the Kindle never change, it is at all time stuck on the loading bar at half. It NEVER shows a menu or moves or anything.
Sadly, I believe that your diagnostic is correct as I can't get the device to do other things that LED life signs and presence of /dev/sdd.
I'll try to tamper with the storage device to see if I can get anything out of it.
Do you think I shoul try to format the partition?
Thanks again.