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Bug 698271 - Brightness doesn't lower past 95%
Brightness doesn't lower past 95%
Status: RESOLVED NOTGNOME
Product: gnome-settings-daemon
Classification: Core
Component: media-keys
3.8.x
Other Linux
: Normal normal
: ---
Assigned To: gnome-settings-daemon-maint
gnome-settings-daemon-maint
: 698273 708618 728354 (view as bug list)
Depends on:
Blocks:
 
 
Reported: 2013-04-18 08:47 UTC by Igor Gnatenko
Modified: 2014-04-24 09:56 UTC
See Also:
GNOME target: ---
GNOME version: ---


Attachments
Xorg.0.log for #698271 (30.09 KB, text/x-log)
2013-04-25 11:15 UTC, Igor Gnatenko
Details
I tested again and was sent to a gnome (923 bytes, application/octet-stream)
2013-04-27 07:11 UTC, Igor Gnatenko
Details

Description Igor Gnatenko 2013-04-18 08:47:42 UTC
Brightness control buttons (on the keyboard) in GNOME is broken.
Buttons on the keyboard brightness is regulated only within 95-100%.
In KDE/XFCE/etc. all works fine.
In gnome-control-center screen all works.
echo ... > /sys/class/backlight/acpi_video0/brightness 
works
/sys/class/backlight/acpi_video0/max_brightness is 100
RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=922192
Comment 1 Igor Gnatenko 2013-04-18 20:50:37 UTC
*** Bug 698273 has been marked as a duplicate of this bug. ***
Comment 2 Matthias Clasen 2013-04-18 23:46:45 UTC
it is not entirely clear what you mean by 'regulated only within 95-100%' - are you saying that your screen brightness doesn't go to 100% with the function keys ?
Comment 3 Igor Gnatenko 2013-04-19 04:45:32 UTC
$ cat /sys/class/backlight/acpi_video0/brightness 
100
I hold Fn+F8 (decrease backlight)
$ cat /sys/class/backlight/acpi_video0/brightness 
95
I change backlight in gnome-control-center screen to 50%
$ cat /sys/class/backlight/acpi_video0/brightness 
50
I hold Fn+F8 (decrease backlight)
$ cat /sys/class/backlight/acpi_video0/brightness 
15
I hold Fn+F9 (increase backlight)
$ cat /sys/class/backlight/acpi_video0/brightness 
75
I want to tell that the keyboard shortcuts don't regulate backligt properly (from 0 to 100)
(In reply to comment #2)
> it is not entirely clear what you mean by 'regulated only within 95-100%' - are
> you saying that your screen brightness doesn't go to 100% with the function
> keys ?
Comment 4 Igor Gnatenko 2013-04-19 04:49:07 UTC
In Debian with Linux kernel 3.2 max_backlight is 15 and regulation happens normally.
Since Linux kernel 3.5 or 3.6 max_backlight is 100 and regulation doesn't work normally.
In Fedora I have 3.8.x kernel
(In reply to comment #2)
> it is not entirely clear what you mean by 'regulated only within 95-100%' - are
> you saying that your screen brightness doesn't go to 100% with the function
> keys ?
Comment 5 Igor Gnatenko 2013-04-20 06:29:55 UTC
What is necessary still information?
(In reply to comment #2)
> it is not entirely clear what you mean by 'regulated only within 95-100%' - are
> you saying that your screen brightness doesn't go to 100% with the function
> keys ?
Comment 6 Bastien Nocera 2013-04-22 15:33:13 UTC
> I want to tell that the keyboard shortcuts don't regulate backligt properly
> (from 0 to 100)

I don't understand what this means.
Comment 7 Igor Gnatenko 2013-04-22 15:48:16 UTC
I uploaded video on YouTube. It hope will help to understand a problem better.
http://www.youtube.com/watch?v=sKJdu22dM_Y
(In reply to comment #6)
> > I want to tell that the keyboard shortcuts don't regulate backligt properly
> > (from 0 to 100)
> 
> I don't understand what this means.
Comment 8 Bastien Nocera 2013-04-23 13:59:29 UTC
Got it. The "lower backlight" button doesn't allow going under 95%. It should be going to 90% (as per BRIGHTNESS_STEP_AMOUNT() with 100 values).

Looks like a problem in the kernel.

Does running this as root work?
/usr/libexec/gsd-backlight-helper --set-brightness 90
Comment 9 Igor Gnatenko 2013-04-23 14:52:58 UTC
Yes. All works.
(In reply to comment #8)
> Got it. The "lower backlight" button doesn't allow going under 95%. It should
> be going to 90% (as per BRIGHTNESS_STEP_AMOUNT() with 100 values).
> 
> Looks like a problem in the kernel.
> 
> Does running this as root work?
> /usr/libexec/gsd-backlight-helper --set-brightness 90
Comment 10 Bastien Nocera 2013-04-23 15:41:25 UTC
(In reply to comment #9)
> Yes. All works.

What does that mean? Does it lower the brightness?
What's the output of:
/usr/libexec/gsd-backlight-helper --get-brightness
?
Comment 11 Igor Gnatenko 2013-04-23 15:43:28 UTC
Yes. It lower the brightness.
# /usr/libexec/gsd-backlight-helper --get-brightness
90
(In reply to comment #10)
> (In reply to comment #9)
> > Yes. All works.
> 
> What does that mean? Does it lower the brightness?
> What's the output of:
> /usr/libexec/gsd-backlight-helper --get-brightness
> ?
Comment 12 Bastien Nocera 2013-04-24 11:21:17 UTC
When reproducing the problem, instead of pressing the brightness down button, can you try launching this command a few times in a row and give me the output?

gdbus call  --session --dest org.gnome.SettingsDaemon.Power --object-path /org/gnome/SettingsDaemon/Power --method org.gnome.SettingsDaemon.Power.Screen.StepDown

Does the same problem happen if you launch this command a few times but waiting a bit between the calls?
Comment 13 Igor Gnatenko 2013-04-24 15:15:25 UTC
I testing in Fedora 18 with gnome 3.6... At the night I will test in Fedora 19 with gnome 3.8.
# LANG=en_US.UTF-8 gdbus call  --session --dest org.gnome.SettingsDaemon.Power --object-path /org/gnome/SettingsDaemon/Power --method org.gnome.SettingsDaemon.Power.Screen.StepDown
Error: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.gnome.SettingsDaemon.Power was not provided by any .service files
(In reply to comment #12)
> When reproducing the problem, instead of pressing the brightness down button,
> can you try launching this command a few times in a row and give me the output?
> 
> gdbus call  --session --dest org.gnome.SettingsDaemon.Power --object-path
> /org/gnome/SettingsDaemon/Power --method
> org.gnome.SettingsDaemon.Power.Screen.StepDown
> 
> Does the same problem happen if you launch this command a few times but waiting
> a bit between the calls?
Comment 14 Bastien Nocera 2013-04-24 15:22:22 UTC
You need to run this as a normal user, not as root.

Under GNOME 3.6, it might be "--dest org.gnome.SettingsDaemon" instead of "--dest org.gnome.SettingsDaemon.Power".
Comment 15 Igor Gnatenko 2013-04-24 15:33:14 UTC
$ ./backlight_test.sh 
Wed Apr 24 19:31:41 MSK 2013
(uint32 95,)
Wed Apr 24 19:31:41 MSK 2013
(uint32 95,)
Wed Apr 24 19:31:42 MSK 2013
(uint32 95,)
Wed Apr 24 19:31:47 MSK 2013
(uint32 95,)
Wed Apr 24 19:31:52 MSK 2013
(uint32 95,)

My script:
#!/bin/sh
LANG=en_US.UTF-8
date
gdbus call  --session --dest org.gnome.SettingsDaemon --object-path /org/gnome/SettingsDaemon/Power --method org.gnome.SettingsDaemon.Power.Screen.StepDown
date
gdbus call  --session --dest org.gnome.SettingsDaemon --object-path /org/gnome/SettingsDaemon/Power --method org.gnome.SettingsDaemon.Power.Screen.StepDown
sleep 1s
date
gdbus call  --session --dest org.gnome.SettingsDaemon --object-path /org/gnome/SettingsDaemon/Power --method org.gnome.SettingsDaemon.Power.Screen.StepDown
sleep 5s
date
gdbus call  --session --dest org.gnome.SettingsDaemon --object-path /org/gnome/SettingsDaemon/Power --method org.gnome.SettingsDaemon.Power.Screen.StepDown
sleep 5s
date
gdbus call  --session --dest org.gnome.SettingsDaemon --object-path /org/gnome/SettingsDaemon/Power --method org.gnome.SettingsDaemon.Power.Screen.StepDown

(In reply to comment #14)
> You need to run this as a normal user, not as root.
> 
> Under GNOME 3.6, it might be "--dest org.gnome.SettingsDaemon" instead of
> "--dest org.gnome.SettingsDaemon.Power".
Comment 16 Bastien Nocera 2013-04-24 15:45:44 UTC
What's the output of xbacklight on your system (it's in the xbacklight package)?

If it returns nothing, it narrows down the problem to 10 lines of code in the power plugin of gnome-settings-daemon, but it's really not obvious what could be broken there.
Comment 17 Igor Gnatenko 2013-04-24 15:55:16 UTC
# /usr/libexec/gsd-backlight-helper --get-brightness
95
# xbacklight 
100.000000
(In reply to comment #16)
> What's the output of xbacklight on your system (it's in the xbacklight
> package)?
> 
> If it returns nothing, it narrows down the problem to 10 lines of code in the
> power plugin of gnome-settings-daemon, but it's really not obvious what could
> be broken there.
Comment 18 Bastien Nocera 2013-04-24 15:58:39 UTC
What hardware is this? It looks like the graphics driver is broken...
Comment 19 Igor Gnatenko 2013-04-24 16:01:58 UTC
Lenovo ThinkPad X230
i7-3520m ( HD 4000 )
(In reply to comment #18)
> What hardware is this? It looks like the graphics driver is broken...
Comment 20 Igor Gnatenko 2013-04-24 16:27:49 UTC
In ThinkPad T430 this bug present. I add my friend in CC list with this notebook.
(In reply to comment #18)
> What hardware is this? It looks like the graphics driver is broken...
Comment 21 Igor Gnatenko 2013-04-24 18:30:12 UTC
> It looks like the graphics driver is broken...
But in KDE/XFCE/etc. all works !
(In reply to comment #18)
> What hardware is this? It looks like the graphics driver is broken...
Comment 22 Igor Gnatenko 2013-04-24 18:58:53 UTC
My friend has tested this bug in GNOME and KDE on ThinkPad T430
Please, watch this video.
http://www.youtube.com/watch?v=WiH1dZ97090
(In reply to comment #18)
> What hardware is this? It looks like the graphics driver is broken...
Comment 23 Bastien Nocera 2013-04-25 09:21:46 UTC
(In reply to comment #21)
> > It looks like the graphics driver is broken...
> But in KDE/XFCE/etc. all works !

Probably because they don't use the backlight provided in the X driver.

> (In reply to comment #18)
> > What hardware is this? It looks like the graphics driver is broken...
Comment 24 Bastien Nocera 2013-04-25 09:30:21 UTC
Do you see any errors in /var/log/Xorg.0.log (or similarly named files, not sure which one is currently used on your system).
Comment 25 Igor Gnatenko 2013-04-25 09:36:07 UTC
(In reply to comment #23)
> (In reply to comment #21)
> > > It looks like the graphics driver is broken...
> > But in KDE/XFCE/etc. all works !
> 
> Probably because they don't use the backlight provided in the X driver.
> 
> > (In reply to comment #18)
> > > What hardware is this? It looks like the graphics driver is broken...
huh. I'm sorry. I didn't know.
(In reply to comment #24)
> Do you see any errors in /var/log/Xorg.0.log (or similarly named files, not
> sure which one is currently used on your system).
$ egrep -w '(WW)|(EE)' /var/log/Xorg.0.log
	(WW) warning, (EE) error, (NI) not implemented, (??) unknown.
[    43.435] (WW) Falling back to old probe method for vesa
[    43.435] (WW) Falling back to old probe method for modesetting
[    43.435] (WW) Falling back to old probe method for fbdev
Comment 26 Igor Gnatenko 2013-04-25 11:15:37 UTC
Created attachment 242403 [details]
Xorg.0.log for #698271
Comment 27 Igor Gnatenko 2013-04-25 13:00:30 UTC
Ajax (https://fedoraproject.org/wiki/User:Ajax) said yesterday that the some problems with backlight are fixed in the intel-gfx.
(In reply to comment #18)
> What hardware is this? It looks like the graphics driver is broken...
Comment 28 Bastien Nocera 2013-04-25 19:59:03 UTC
(In reply to comment #27)
> Ajax (https://fedoraproject.org/wiki/User:Ajax) said yesterday that the some
> problems with backlight are fixed in the intel-gfx.

Ajax actually said that it was a bug in the intel-gfx driver, not that it was fixed.

You should go ahead and file a bug against the intel-gfx driver as per:
https://01.org/linuxgraphics/documentation/how-report-bugs-0
Comment 29 Igor Gnatenko 2013-04-25 20:53:04 UTC
(In reply to comment #28)
> (In reply to comment #27)
> > Ajax (https://fedoraproject.org/wiki/User:Ajax) said yesterday that the some
> > problems with backlight are fixed in the intel-gfx.
> 
> Ajax actually said that it was a bug in the intel-gfx driver, not that it was
> fixed.
> 
> You should go ahead and file a bug against the intel-gfx driver as per:
> https://01.org/linuxgraphics/documentation/how-report-bugs-0
I created bug: 
https://bugs.freedesktop.org/show_bug.cgi?id=63931
Thanks you very much =)
Comment 30 Igor Gnatenko 2013-04-27 07:11:02 UTC
Created attachment 242640 [details]
I tested again and was sent to a gnome

I tested again and was sent to a gnome (https://bugzilla.kernel.org/show_bug.cgi?id=57131)
Comment 31 Aaron Lu 2013-04-27 07:42:05 UTC
Hi Bastien,

According to Igor's test report:

[root@brain-ThinkPad-X230 acpi_video0]# cat max_brightness 
100
[root@brain-ThinkPad-X230 acpi_video0]# cat brightness 
100
[root@brain-ThinkPad-X230 acpi_video0]# xbacklight 
100.000000
[root@brain-ThinkPad-X230 acpi_video0]# /usr/libexec/gsd-backlight-helper --get-brightness
100
[root@brain-ThinkPad-X230 acpi_video0]# /usr/libexec/gsd-backlight-helper --set-brightness 90
[root@brain-ThinkPad-X230 acpi_video0]# /usr/libexec/gsd-backlight-helper --get-brightness
90
[root@brain-ThinkPad-X230 acpi_video0]# xbacklight 
90.000000
[root@brain-ThinkPad-X230 acpi_video0]# cat brightness 
90
[brain@brain-ThinkPad-X230 acpi_video0]$ gdbus call  --session --dest org.gnome.SettingsDaemon --object-path /org/gnome/SettingsDaemon/Power --method org.gnome.SettingsDaemon.Power.Screen.StepDown
(uint32 85,)
[root@brain-ThinkPad-X230 acpi_video0]# xbacklight 
90.000000
[root@brain-ThinkPad-X230 acpi_video0]# cat brightness 
90

It looks like the gdbus call doesn't have an effect. Igor said that manually change the backlight level through the acpi video interface works(with echo).
Comment 32 Bastien Nocera 2013-04-27 20:45:44 UTC
1) You didn't test whether changing the backlight through xbacklight worked
2) gsd-backlight-helper isn't used or called in GNOME if the driver offers XRandR backlight support

Run:
xbacklight -dec 5
and then:
xbacklight

should show whether changing the brightness through the backlight interface works.
Comment 33 Igor Gnatenko 2013-04-27 20:49:16 UTC
(In reply to comment #32)
> 1) You didn't test whether changing the backlight through xbacklight worked
> 2) gsd-backlight-helper isn't used or called in GNOME if the driver offers
> XRandR backlight support
> 
> Run:
> xbacklight -dec 5
> and then:
> xbacklight
> 
> should show whether changing the brightness through the backlight interface
> works.
huh! 
$ xbacklight 
100.000000
$ xbacklight -dec 5
$ xbacklight 
100.000000
$ xbacklight -dec 10
$ xbacklight 
90.000000
$ xbacklight -inc 5
$ xbacklight 
90.000000
$ xbacklight -inc 10
$ xbacklight 
100.000000
and backlight lower...
Comment 34 Igor Gnatenko 2013-04-27 20:50:36 UTC
(In reply to comment #33)
> (In reply to comment #32)
> > 1) You didn't test whether changing the backlight through xbacklight worked
> > 2) gsd-backlight-helper isn't used or called in GNOME if the driver offers
> > XRandR backlight support
> > 
> > Run:
> > xbacklight -dec 5
> > and then:
> > xbacklight
> > 
> > should show whether changing the brightness through the backlight interface
> > works.
> huh! 
> $ xbacklight 
> 100.000000
> $ xbacklight -dec 5
> $ xbacklight 
> 100.000000
> $ xbacklight -dec 10
> $ xbacklight 
> 90.000000
> $ xbacklight -inc 5
> $ xbacklight 
> 90.000000
> $ xbacklight -inc 10
> $ xbacklight 
> 100.000000
> and backlight lower...
sorry. real backlight is equal to that shows xbacklight
Comment 35 Igor Gnatenko 2013-04-27 20:58:20 UTC
(In reply to comment #32)
> 1) You didn't test whether changing the backlight through xbacklight worked
> 2) gsd-backlight-helper isn't used or called in GNOME if the driver offers
> XRandR backlight support
> 
> Run:
> xbacklight -dec 5
> and then:
> xbacklight
> 
> should show whether changing the brightness through the backlight interface
> works.
$ xbacklight -set 99
$ xbacklight 
100.000000
$ xbacklight -set 95
$ xbacklight 
100.000000
$ xbacklight -set 91
$ xbacklight 
100.000000
Comment 36 Bastien Nocera 2013-04-27 21:05:12 UTC
If xbacklight shows the same symptons as gnome-settings-daemon, I'm afraid that's about how far I can go to fix this problem.

Given that setting the backlight directly (through sysfs) to values like 95% works but doesn't through xbacklight, either xbacklight is broken, or the driver is doing something wrong.

Aron, let me know if I'm wrong here.
Comment 37 Aaron Lu 2013-04-28 02:14:46 UTC
(In reply to comment #36)
> If xbacklight shows the same symptons as gnome-settings-daemon, I'm afraid
> that's about how far I can go to fix this problem.
> 
> Given that setting the backlight directly (through sysfs) to values like 95%
> works but doesn't through xbacklight, either xbacklight is broken, or the
> driver is doing something wrong.
> 
> Aron, let me know if I'm wrong here.

I don't know anything about xbacklight :-)
Care to explain what does "driver is doing something wrong" mean here? Is it the xorg driver providing information for xbacklight?
Comment 38 Igor Gnatenko 2013-04-28 04:47:35 UTC
(In reply to comment #37)
> (In reply to comment #36)
> > If xbacklight shows the same symptons as gnome-settings-daemon, I'm afraid
> > that's about how far I can go to fix this problem.
> > 
> > Given that setting the backlight directly (through sysfs) to values like 95%
> > works but doesn't through xbacklight, either xbacklight is broken, or the
> > driver is doing something wrong.
> > 
> > Aron, let me know if I'm wrong here.
> 
> I don't know anything about xbacklight :-)
> Care to explain what does "driver is doing something wrong" mean here? Is it
> the xorg driver providing information for xbacklight?
Aaron Lu, see this comment please.
https://bugs.freedesktop.org/show_bug.cgi?id=63931#c11
Comment 39 Igor Gnatenko 2013-04-29 08:56:37 UTC
I found bug in BZ Kernel!
https://bugzilla.kernel.org/show_bug.cgi?id=51231
https://patchwork.kernel.org/patch/2124861/
Comment 40 Bastien Nocera 2013-09-23 12:57:14 UTC
*** Bug 708618 has been marked as a duplicate of this bug. ***
Comment 41 Bastien Nocera 2014-04-24 09:56:29 UTC
*** Bug 728354 has been marked as a duplicate of this bug. ***