[ltp] Brightness problem on x301 running Debian Lenny

Pethe Milan linux-thinkpad@linux-thinkpad.org
Sun, 1 Feb 2009 20:57:33 +0000


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Hi!

# pwd
/usr/share/hal/fdi/information/10freedesktop

#cat 10-laptop-panel-hardware.fdi

      <match key="linux.sysfs_path"
string="/sys/class/backlight/thinkpad_screen">
        <merge key="laptop_panel.brightness_in_hardware"
type="bool">true</merge>
      </match>

bye,
Pethe Milan

On Sun, Feb 1, 2009 at 7:59 PM, Per Dalgas Jakobsen <pdj@knaldgas.dk> wrote:

> Hi,
>
> I have a strange problem on my x301 with the monitor brightness. It is like
> the actual brightness level lacks one behind all the time, let me explain:
> ---
> I press Fn+Home (brightness up) until the monitor is as bright as possible,
> then pressing Fn+End (brightness down), does nothing, second Fn+End brings
> down the brightness, if I then press Fn+Home, the brightness goes down once
> more (not up), the next brightness adjustment will go up no matter which
> Fn+Home or Fn+End I press, because I pressed Fn+Home previously.
>
> I also tried to write values directly to the
> /proc/acpi/video/VID/LCD0/brightness:
> ---
> # echo 100 >/proc/acpi/video/VID/LCD0/brightness (behaviour depends on
> previous adjustment)
> # echo 80 >/proc/acpi/video/VID/LCD0/brightness (brightness goes to 100)
> # echo 70 >/proc/acpi/video/VID/LCD0/brightness (brightness goes to 80)
> # echo [any number] >/proc/acpi/video/VID/LCD0/brightness (brightness goes
> to 70)
>
> I'm running a self-compiled (and self-configured) kernel version 2.6.28 -
> Almost all used modules are compiled into the kernel.
> I've tried to run an Ubuntu LiveCD - That one operates as expected.
>
> Any ideas of why Debian Lenny with kernel 2.6.28 does not behave reasonable
> on LCD brightness changes?
>
> ~Per
>
> --
> The linux-thinkpad mailing list home page is at:
> http://mailman.linux-thinkpad.org/mailman/listinfo/linux-thinkpad
>

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Hi!<br><br># pwd<br>/usr/share/hal/fdi/information/10freedesktop<br><br>#ca=
t 10-laptop-panel-hardware.fdi<br><br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &lt;ma=
tch key=3D&quot;linux.sysfs_path&quot; string=3D&quot;/sys/class/backlight/=
thinkpad_screen&quot;&gt;<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &lt;merge key=3D&quot;laptop_pan=
el.brightness_in_hardware&quot; type=3D&quot;bool&quot;&gt;true&lt;/merge&g=
t;<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &lt;/match&gt;<br><br>bye,<br>Pethe Mi=
lan<br><br><div class=3D"gmail_quote">On Sun, Feb 1, 2009 at 7:59 PM, Per D=
algas Jakobsen <span dir=3D"ltr">&lt;<a href=3D"mailto:pdj@knaldgas.dk">pdj=
@knaldgas.dk</a>&gt;</span> wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"border-left: 1px solid rgb(204, =
204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Hi,<br>
<br>
I have a strange problem on my x301 with the monitor brightness. It is like=
 the actual brightness level lacks one behind all the time, let me explain:=
<br>
---<br>
I press Fn+Home (brightness up) until the monitor is as bright as possible,=
 then pressing Fn+End (brightness down), does nothing, second Fn+End brings=
 down the brightness, if I then press Fn+Home, the brightness goes down onc=
e more (not up), the next brightness adjustment will go up no matter which =
Fn+Home or Fn+End I press, because I pressed Fn+Home previously.<br>

<br>
I also tried to write values directly to the /proc/acpi/video/VID/LCD0/brig=
htness:<br>
---<br>
# echo 100 &gt;/proc/acpi/video/VID/LCD0/brightness (behaviour depends on p=
revious adjustment)<br>
# echo 80 &gt;/proc/acpi/video/VID/LCD0/brightness (brightness goes to 100)=
<br>
# echo 70 &gt;/proc/acpi/video/VID/LCD0/brightness (brightness goes to 80)<=
br>
# echo [any number] &gt;/proc/acpi/video/VID/LCD0/brightness (brightness go=
es to 70)<br>
<br>
I&#39;m running a self-compiled (and self-configured) kernel version 2.6.28=
 - Almost all used modules are compiled into the kernel.<br>
I&#39;ve tried to run an Ubuntu LiveCD - That one operates as expected.<br>
<br>
Any ideas of why Debian Lenny with kernel 2.6.28 does not behave reasonable=
 on LCD brightness changes?<br>
<br>
~Per<br><font color=3D"#888888">
<br>
-- <br>
The linux-thinkpad mailing list home page is at:<br>
<a href=3D"http://mailman.linux-thinkpad.org/mailman/listinfo/linux-thinkpa=
d" target=3D"_blank">http://mailman.linux-thinkpad.org/mailman/listinfo/lin=
ux-thinkpad</a><br>
</font></blockquote></div><br>

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