FS#51714 : [linux] function key for screen brightness broken

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FS#51714 - [linux] function key for screen brightness broken

Attached to Project: Arch Linux
Opened by Noha Philip (Nomad21) - Sunday, 06 November 2016, 06:48 GMT
Last edited by Andreas Radke (AndyRTR) - Tuesday, 17 March 2020, 09:42 GMT

Task Type	Bug Report
Category	System
Status	Closed
Assigned To	Andreas Radke (AndyRTR) Jan Alexander Steffens (heftig)
Architecture	x86_64
Severity	Medium
Priority	Normal
Reported Version
Due in Version	Undecided
Due Date	Undecided
Percent Complete
Votes	0
Private	No

Details

Description:
Changing the brightness using function key is buggy. The key is working but the problem is when the value changes. Using 'cat /sys/class/backlight/intel_backlight/brightness' I got the brightness values as such:

244
488
976
488
976
4882 (max)
4394
244

As you can see the values are not changed equally (like increase 10% each time).

Additional info:
* package version(s)
* config and/or log files etc.

Arch kernel version: 4.8.6-1-ARCH
The error log is attached, please let me know if more information is required.

Steps to reproduce:
This bug started occurring after full system upgrade. 'pacman -Syu'