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Controlling backlight on thinkpad x60

DISCUSSION Pavel Machek 2 participants 7 messages Sep 8, 2008 – Sep 9, 2008 ACPI

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#0 lore raw

Hi!

Some time ago, FN-Home/End just adjusted the brightness, and /proc/acpi/ibm contained backlight control.

In 2.6.27-rc5, /proc/acpi/ibm does not contain backlight control and /sys/class/backlight is empty...

(I do have CONFIG_ACPI_VIDEO disabled, it killed my machine last time I enabled it, is it mandatory now?)
Pavel

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#1 lore raw
Quoted 2 lines · Pavel Machek

(I do have CONFIG_ACPI_VIDEO disabled, it killed my machine last time I enabled it, is it mandatory now?)

On Thinkpads with ACPI video support, yes.

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Matthew Garrett | [email protected]
#2 lore raw
Quoted 6 lines · Matthew Garrett
Quoted 2 lines · Pavel Machek

(I do have CONFIG_ACPI_VIDEO disabled, it killed my machine last time I enabled it, is it mandatory now?)

On Thinkpads with ACPI video support, yes.

That's bad then, because ACPI video support does not work here. I can boot, and even Fn-home/end works, but it breaks with X.

In old versions, it resulted on black screen after LID close in X.

In 2.6.27-rc5, screen goes black as soon as X are started.

(In old versions, I could use ibm-acpi, and fn-home/end worked even without CONFIG_ACPI_VIDEO...)

Pavel

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(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
#3 lore raw
Quoted 6 lines · Pavel Machek
Quoted 5 lines · Matthew Garrett
Quoted 2 lines · Pavel Machek

(I do have CONFIG_ACPI_VIDEO disabled, it killed my machine last time I enabled it, is it mandatory now?)

Quoted 8 lines
Quoted 1 line

On Thinkpads with ACPI video support, yes.

That's bad then, because ACPI video support does not work here. I can boot, and even Fn-home/end works, but it breaks with X.

In old versions, it resulted on black screen after LID close in X.

In 2.6.27-rc5, screen goes black as soon as X are started.

Hmm, I have updated my X server, and it now works with ACPI_VIDEO... which means that this is probably not affecting huge number of people.

Hmm... something is still funny. I have

root@amd:/sys/class/backlight/acpi_video0# echo 1 > brightness
root@amd:/sys/class/backlight/acpi_video0# echo 0 > brightness
root@amd:/sys/class/backlight/acpi_video0# cd ../acpi_video1/
root@amd:/sys/class/backlight/acpi_video1# echo 0 > brightness
root@amd:/sys/class/backlight/acpi_video1# echo 7 > brightness
root@amd:/sys/class/backlight/acpi_video1# echo 0 > brightness

...and both acpi_video0 *and* acpi_video1 works... strange.
Pavel

Signature · 2 lines
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
#4 lore raw
In reply to Pavel Machek
Quoted 4 lines · Pavel Machek

That's bad then, because ACPI video support does not work here. I can boot, and even Fn-home/end works, but it breaks with X.

In old versions, it resulted on black screen after LID close in X.

Yeah, X did retarded things in response to video events. That's been fixed for ages.

Quoted 1 line

In 2.6.27-rc5, screen goes black as soon as X are started.

That sounds bizarre, and I can't reproduce it here.

Signature · 1 line
Matthew Garrett | [email protected]
#5 lore raw
Quoted 4 lines · Matthew Garrett
Quoted 3 lines · Pavel Machek

That's bad then, because ACPI video support does not work here. I can boot, and even Fn-home/end works, but it breaks with X.

Quoted 8 lines
Quoted 1 line

In old versions, it resulted on black screen after LID close in X.

Yeah, X did retarded things in response to video events. That's been fixed for ages.

Quoted 1 line

In 2.6.27-rc5, screen goes black as soon as X are started.

That sounds bizarre, and I can't reproduce it here.

It was same old X. New X fix that. But I still have two backlight devices...

Pavel

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(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
#6 lore raw
Quoted 1 line · Pavel Machek

It was same old X. New X fix that. But I still have two backlight devices...

Should be fixed in .28. Sorry about that, confusion over which DRM branches were getting merged meant it missed .27.

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Matthew Garrett | [email protected]