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On my laptop PC with dual boot I am unable to activate the keyboard backlight when running Ubuntu, although it works fine in Windows.

How can I get my backlight to work under Ubuntu? Here are the main characteristics of the PC as well as its system:

$ sudo lshw
description: Ordinateur Bloc-notes
product: SVF13N1C5E (54678237)
vendor: Sony Corporation

$ cat /proc/version
Linux version 4.15.0-34-generic (buildd@lgw01-amd64-047) (gcc version 7.3.0 (Ubuntu 7.3.0-16ubuntu3)) #37-Ubuntu SMP Mon Aug 27 15:21:48 UTC 2018

marked as duplicate by Community Sep 19 '18 at 13:07

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  • What happens if you run echo 1 | sudo tee -a /sys/devices/platform/sony-laptop/kbd_backlight? – terdon Sep 19 '18 at 12:16
  • response is -> $ echo 1 | sudo tee -a /sys/devices/platform/sony-laptop/kbd_backlight 1 ->> now I do have backlight when typing, bat not yet on keyboard handover. but anyway it satisfies me as it is now. Thanks lot ! – viki Sep 19 '18 at 12:55
  • That isn't a solution, I'm afraid. It will go away when you reboot. But at least now we know what's needed. What is "keyboard handover"? – terdon Sep 19 '18 at 14:36