2013-07-23 07:52:17

by Jörg Otte

[permalink] [raw]
Subject: [v3.11-rc2] regression: brightness always on maximum.

The brightness of my laptop is always on maximum and can't be scaled
down.
Brightness control via function keys was always working on this
laptop, so this is a regression in v3.11-rc2.

It is a FUJITSU LIFEBOOK AH532/FJNBB1C, BIOS Version 1.09 05/22/2012
Video driver is i915.

Please Cc me in answeres , I am not subscribed.

Thanks, Jörg


2013-07-23 23:47:25

by Rafael J. Wysocki

[permalink] [raw]
Subject: Re: [v3.11-rc2] regression: brightness always on maximum.

On Tuesday, July 23, 2013 09:52:15 AM Jörg Otte wrote:
> The brightness of my laptop is always on maximum and can't be scaled
> down.
> Brightness control via function keys was always working on this
> laptop, so this is a regression in v3.11-rc2.

Is there any other way to control brightness on your system (eg. through a GUI)?

If so, does it work?

Also, does reverting commit efaa14c help? If it doesn't help, does reverting
commit 8c5bd7a too (so that both are reverted) help?

Rafael

2013-07-24 06:41:32

by Aaron Lu

[permalink] [raw]
Subject: Re: [v3.11-rc2] regression: brightness always on maximum.

On 07/23/2013 03:52 PM, Jörg Otte wrote:
> The brightness of my laptop is always on maximum and can't be scaled
> down.
> Brightness control via function keys was always working on this
> laptop, so this is a regression in v3.11-rc2.

Please list /sys/class/backlight.

If there is a intel_backlight, please try to adjust brightness level
through brightness file like this:
# echo XXX > /sys/class/backlight/intel_backlight/brightness
Does it work?

Thanks,
Aaron

>
> It is a FUJITSU LIFEBOOK AH532/FJNBB1C, BIOS Version 1.09 05/22/2012
> Video driver is i915.
>
> Please Cc me in answeres , I am not subscribed.
>
> Thanks, Jörg
> --
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2013-07-24 10:57:04

by Jörg Otte

[permalink] [raw]
Subject: Re: [v3.11-rc2] regression: brightness always on maximum.

2013/7/24 Aaron Lu <[email protected]>:
> On 07/23/2013 03:52 PM, Jörg Otte wrote:
>> The brightness of my laptop is always on maximum and can't be scaled
>> down.
>> Brightness control via function keys was always working on this
>> laptop, so this is a regression in v3.11-rc2.
>
> Please list /sys/class/backlight.

# cd /sys/class
# find backlight -name "*"
backlight
backlight/intel_backlight
# cd backlight/intel_backlight
# ls
actual_brightness bl_power brightness device max_brightness power
subsystem type uevent
# cat actual_brightness
0
# cat max_brightness
4882

actual_brightness is 0, but brightness is on maximum!

>
> If there is a intel_backlight, please try to adjust brightness level
> through brightness file like this:
> # echo XXX > /sys/class/backlight/intel_backlight/brightness
> Does it work?

no, it doesn't have any visible effect.


Thanks, Jörg

2013-07-24 11:32:32

by Jörg Otte

[permalink] [raw]
Subject: Re: [v3.11-rc2] regression: brightness always on maximum.

2013/7/24 Rafael J. Wysocki <[email protected]>:
> On Tuesday, July 23, 2013 09:52:15 AM Jörg Otte wrote:
>> The brightness of my laptop is always on maximum and can't be scaled
>> down.
>> Brightness control via function keys was always working on this
>> laptop, so this is a regression in v3.11-rc2.
>
> Is there any other way to control brightness on your system (eg. through a GUI)?
Yes

> If so, does it work?
No, it has no visible effect.

> Also, does reverting commit efaa14c help?
No

> If it doesn't help, does reverting
> commit 8c5bd7a too (so that both are reverted) help?
Yes, reverting both fixes the problem for me.

Thanks, Jörg