Keyboard backlight control does not work on some dell laptops.
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
HWE Next |
Fix Released
|
Undecided
|
Unassigned | ||
linux (Ubuntu) |
Fix Released
|
Undecided
|
Kai-Heng Feng | ||
Xenial |
Fix Released
|
Medium
|
Unassigned | ||
Yakkety |
Fix Released
|
Medium
|
Unassigned | ||
Zesty |
Fix Released
|
Medium
|
Unassigned |
Bug Description
[Impact]
There's no sysfs node for some Dell laptop keyboard backlight control.
Two issues here:
1. No sysfs "/sys/devices/
The patch fixes the issue by adding necessary DMI string to dmi whitelist table:
commit 8d2c4538dbc7154
Author: Alex Hung <email address hidden>
Date: Thu Feb 16 20:58:03 2017 +0800
platform/x86: dell-laptop: Add Latitude 7480 and others to the DMI whitelist
2. The sysfs exits, but backlight cannot be controlled by "brightness" attribute.
The patch fixes the issue by updating timeout AC, if the model supports it:
commit 9216e0dcb5533a9
Author: Pali Rohár <email address hidden>
Date: Sun Apr 23 21:40:47 2017 +0200
platform/x86: dell-laptop: Add keyboard backlight timeout AC settings
[Test Case]
On Dell Precision 3250 (Kabylake generation), the backlight cannot be controlled in sysfs, because it does not exist.
With these two patches, keyboard backlight can be controlled in "/sys/devices/
[Regression Potential]
The regression potential is low. Only newer Dell laptops will be affected, and it only applies to limited models.
tags: | added: originate-from-1689427 somerville |
description: | updated |
Changed in linux (Ubuntu Xenial): | |
status: | New → Fix Committed |
Changed in linux (Ubuntu Zesty): | |
status: | New → Fix Committed |
importance: | Undecided → Medium |
Changed in linux (Ubuntu Xenial): | |
importance: | Undecided → Medium |
Changed in linux (Ubuntu Yakkety): | |
importance: | Undecided → Medium |
Changed in linux (Ubuntu Yakkety): | |
status: | New → Fix Committed |
Changed in linux (Ubuntu): | |
status: | Confirmed → Fix Released |
Changed in hwe-next: | |
status: | New → Fix Released |
Hi Heng Feng,
How many days do you think will be needed to finish this backing port?