Bug 110973

Summary:	GeForce GT 750M Mac Edition backlight
Product:	Mesa	Reporter:	Alexey Kuznetsov <axet>
Component:	Drivers/DRI/nouveau	Assignee:	Nouveau Project <nouveau>
Status:	RESOLVED MOVED	QA Contact:	Nouveau Project <nouveau>
Severity:	normal
Priority:	medium	CC:	imirkin
Version:	unspecified
Hardware:	Other
OS:	All
Whiteboard:
i915 platform:		i915 features:
Attachments:	sudo acpidump -o acpidump.txt sudo fwts > fwts sudo fwts method > fwts_method sudo dmidecode > dmidecode.log grep -r . /proc/acpi > acpi

Description Alexey Kuznetsov 2019-06-23 20:50:45 UTC

Created attachment 144616 [details]
sudo acpidump -o acpidump.txt

Hello!

I notice when laptop display went off, it keep backlight on.

Technically speaking this:

# xset dpms force off

only set screen to black, without turning off LCD backlight.

My kernel has "acpi_backlight=vendor" which enables backlight control from function keys and gnome recognize those actions by displaying popup with current brightness level.

Everything seems works fine, I've been able to turn display off using:

# echo 0 > /sys/devices/pnp0/00:03/backlight/gmux_backlight/brightness

But still no luck with 'xset'.

axet@axet-laptop:~$ ls -al /sys/class/backlight/
total 0
drwxr-xr-x  2 root root 0 июн 23 23:13 .
drwxr-xr-x 67 root root 0 июн 23 23:13 ..
lrwxrwxrwx  1 root root 0 июн 23 23:13 gmux_backlight -> ../../devices/pnp0/00:03/backlight/gmux_backlight
axet@axet-laptop:~$



Maybe related: https://bugs.freedesktop.org/show_bug.cgi?id=106869

Comment 1 Alexey Kuznetsov 2019-06-23 20:51:24 UTC

Created attachment 144617 [details]
sudo fwts > fwts

Comment 2 Alexey Kuznetsov 2019-06-23 20:51:43 UTC

Created attachment 144618 [details]
sudo fwts method > fwts_method

Comment 3 Alexey Kuznetsov 2019-06-23 20:52:09 UTC

Created attachment 144619 [details]
sudo dmidecode > dmidecode.log

Comment 4 Alexey Kuznetsov 2019-06-23 20:53:36 UTC

Created attachment 144620 [details]
grep -r . /proc/acpi > acpi

Comment 5 Alexey Kuznetsov 2019-06-23 20:54:45 UTC

PS: I do not remember, if it is ever worked.

Comment 6 Alexey Kuznetsov 2019-08-31 10:26:52 UTC

Interesting note. After suspend/resume it starts to work properly.

Comment 7 GitLab Migration User 2019-09-18 20:48:07 UTC

-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/mesa/mesa/issues/1181.

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