Re: Fwd: Brightness on HP EliteBook 8460p

["Pali Rohár" <pali.rohar@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 2362 bytes --]

On Friday 09 December 2011 16:46:29 Pali Rohár wrote:
> On Friday 09 December 2011 22:49:09 joeyli wrote:
> > Hi Pali,
> > 
> > 於 五，2011-12-09 於 22:36 +0800，Li Joey 提到：
> > 
> > > ---------- Forwarded message ----------
> > > From: Pali Rohár <pali.rohar@gmail.com>
> > > Date: 2011/7/15
> > > Subject: Brightness on HP EliteBook 8460p
> > > To: linux-acpi@vger.kernel.org
> > > 
> > > 
> > > Hello,
> > > 
> > > on my HP EliteBook 8460p is not possible to set display brightness
> > > when ACPI
> > > is enabled in kernel. Entries in sysfs is properly created without
> > > errors. But
> > > when I try write any value
> > > to /sys/class/backlight/acpi_video0/brightness
> > > nothing happened (and no error is in dmesg). When I press Fn key for
> > > chaining
> > > display brightness kernel send correct key event (tested with xev)
> > > but
> > > nothing
> > > happened too.
> > > 
> > > When I disabled ACPI (acpi=off in kernel command line) all Fn keys
> > > are
> > > broken
> > > and not working (no events in xev). But brightness keys working (I
> > > think on HW
> > > level, because xev does not see it) - increase and decrease display
> > > brightness.
> > > 
> > > So what can I do with my notebook? I think that there is error/bug
> > > in
> > > BIOS or
> > > ACPI because with disabled ACPI brightness working. But with
> > > disabled
> > > ACPI is
> > > notebook unuseable (no battery info, no Fn keys, no WIFI rfkill,
> > > ...).
> > > Can
> > > somebody help me with this problem?
> > > 
> > > --
> > > Pali Rohár
> > > pali.rohar@gmail.com
> > 
> > You can try to put kernel parameter:
> > 	acpi_osi="!Windows 2009"
> > 
> > to /boot/grub/menu.lst, then reboot look at maybe better.
> > 
> > And,
> > could you please kindly share DSDT and dmidecode to me?
> > 
> > Plesae login by root then:
> > 	% acpidump > acpidump.dat
> > 	% dmidecode > dmidecode.log
> > 
> > Thanks a lot!
> > Joey Lee
> 
> Hello,
> 
> adding any acpi_osi values did not changed anything (also tried other osi
> strings from decompiled DSDT table). Brightness problem is in both BIOS and
> UEFI boot mode.
> 
> I attached acpidump and dmidecode output from bios and uefi mode too.

Did you find way how to control display brightness?

-- 
Pali Rohár
pali.rohar@gmail.com

[-- Attachment #2: This is a digitally signed message part. --]
[-- Type: application/pgp-signature, Size: 198 bytes --]