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From: Lukas Hejtmanek <>
To: Henrique de Moraes Holschuh <>
Subject: Re: 2.6.25-rc1 regression - IBM ACPI backlight
Date: Fri, 15 Feb 2008 12:02:13 +0100	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

On Thu, Feb 14, 2008 at 10:24:52AM -0200, Henrique de Moraes Holschuh wrote:
> > as of 2.6.25-rc1, there is no more /sys/class/backlight/acpi_video1 which
> > controlled LVDS backlight on Lenovo ThinkPad T61. There is still
> > acpi_video0 which seems to have sane values but echo N > brightness has no
> > effect at all.
> > 
> > thinkpad_acpi module reports that ACPI controlled backlight is present.
> Please report this to linux-acpi @ vger . kernel . org...
> It is likely caused by the stuff to locate and disable the unused video
> device in the DSDT (apparently it got the wrong device?!).
> However, BEFORE reporting to linux-acpi, please test it in single user mode
> without X *ever* being loaded on that boot.  New X disables the BIOS
> brightness changes that ACPI uses.

2.6.24 kernel has two acpi_video[01]. 2.6.25-rc1 does not, it contains only
acpi_video0 (even in text mode in single user without X being loaded) which
does not work at all.

Lukáš Hejtmánek

  reply	other threads:[~2008-02-15 11:02 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-02-14 10:38 Lukas Hejtmanek
2008-02-14 12:24 ` Henrique de Moraes Holschuh
2008-02-15 11:02   ` Lukas Hejtmanek [this message]
2008-02-15 11:50     ` Henrique de Moraes Holschuh
2008-02-15 12:07     ` Matthew Garrett
2008-02-15 12:53       ` Lukas Hejtmanek

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