Bug 1374071

Summary:	Screen brightness adjustment stopped working with 4.7.2 kernel
Product:	[Fedora] Fedora	Reporter:	Johan Heikkila <johan.heikkila>
Component:	kernel	Assignee:	Kernel Maintainer List <kernel-maint>
Status:	CLOSED WORKSFORME	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	24	CC:	gansalmon, ichavero, itamar, johan.heikkila, jonathan, kernel-maint, madhu.chinakonda, mchehab
Target Milestone:	---
Target Release:	---
Hardware:	x86_64
OS:	Linux
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Fixed In Version:		Doc Type:	If docs needed, set a value
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Clone Of:		Environment:
Last Closed:	2016-10-15 19:55:22 UTC	Type:	Bug
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
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Description Johan Heikkila 2016-09-07 21:01:14 UTC

Description of problem:
Screen brightness stopped working with kernel 4.7.2 on MSI GE60 laptop. It works fine with 4.6.7 and older kernels (as long as I can remember it has been working). When adding "acpi_osi=" to the GRUB command line it works also in kernel 4.7.2.

Version-Release number of selected component (if applicable):
4.7.2-201.fc24.x86_64

How reproducible:
Always

Steps to Reproduce:
1. Boot PC with 4.7.2 kernel
2. Hit Fn+Up, Fn+Down

Actual results:
Brightness doesn't change

Expected results:
Brightness should change

Additional info:

This is an MSI GE60 laptop. 
Brightness change works with 4.6 and older kernels.

"acpi_osi=" (null) kernel command line fixes it in 4.7.2 kernel for this laptop.
Command lines "acpi_osi=Linux" "video.use_native_backlight=1" and "acpi_backlight=vendor" do not work.
Previous kernels 4.6 and older didn't need any command line options.

Output with working backlight:

[root@msi ~]# ls /sys/class/backlight
acpi_video0  acpi_video1  intel_backlight

Output with non-working backligt:

[root@msi ~]# ls /sys/class/backlight
intel_backlight



[root@msi ~]# grep '.*' /sys/class/dmi/id/*_* 2> /dev/null
/sys/class/dmi/id/bios_date:03/12/2013
/sys/class/dmi/id/bios_vendor:American Megatrends Inc.
/sys/class/dmi/id/bios_version:E16GAIMS.514
/sys/class/dmi/id/board_asset_tag:To be filled by O.E.M.
/sys/class/dmi/id/board_name:MS-16GA
/sys/class/dmi/id/board_serial:BSS-0123456789
/sys/class/dmi/id/board_vendor:Micro-Star International Co., Ltd.
/sys/class/dmi/id/board_version:REV:1.0
/sys/class/dmi/id/chassis_asset_tag:No Asset Tag
/sys/class/dmi/id/chassis_serial:None
/sys/class/dmi/id/chassis_type:10
/sys/class/dmi/id/chassis_vendor:Micro-Star International Co., Ltd.
/sys/class/dmi/id/chassis_version:N/A
/sys/class/dmi/id/product_name:GE60 0NC\0ND
/sys/class/dmi/id/product_serial:FFFFFFFF
/sys/class/dmi/id/product_uuid:03000200-0400-0500-0006-000700080009
/sys/class/dmi/id/product_version:REV:1.0
/sys/class/dmi/id/sys_vendor:Micro-Star International Co., Ltd.


[root@msi etc]# lsmod|grep msi
msi_wmi                16384  0
wmi                    16384  2 msi_wmi,mxm_wmi
msi_laptop             16384  0
rfkill                 24576  8 cfg80211,msi_laptop,bluetooth
sparse_keymap          16384  2 msi_laptop,msi_wmi
video                  40960  3 i915,msi_laptop,msi_wmi

The msi_wmi module seems a bit broken for this laptop. It has always printed "msi_wmi: Unknown event received" when changing brightness (and still does), but it doesn't seem to matter for the brightness.

Comment 1 Johan Heikkila 2016-09-21 18:44:50 UTC

Still same problem in 4.7.3 kernel.

Comment 2 Laura Abbott 2016-09-23 19:08:15 UTC

*********** MASS BUG UPDATE **************
 
We apologize for the inconvenience.  There is a large number of bugs to go through and several of them have gone stale.  Due to this, we are doing a mass bug update across all of the Fedora 24 kernel bugs.
 
Fedora 24 has now been rebased to 4.7.4-200.fc24.  Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel.
 
If you have moved on to Fedora 25, and are still experiencing this issue, please change the version to Fedora 25.
 
If you experience different issues, please open a new bug report for those.

Comment 3 Johan Heikkila 2016-09-23 19:21:52 UTC

Still the same problem with 4.7.4-200.fc24.x86_64 kernel.

Comment 4 Johan Heikkila 2016-10-15 19:55:22 UTC

This appears to be fixed now in 4.7.5, 4.7.6 and 4.7.7 kernels.