Re: Fwd: Brightness on HP EliteBook 8460p

[joeyli <jlee@suse.com>]

於 二，2011-12-20 於 14:20 +0100，Pali Rohár 提到：
> On Tuesday 20 December 2011 16:13:39 joeyli wrote:
> > > > > 
> > > > > 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?
> > > 
> > > I am really sorry for I am sticking on another tough issue.
> > > I will look at your DSDT tomorrow.
> > > 
> > > 
> > > Thanks
> > > Joey Lee
> > 
> > I just look at the DSDT of HP EliteBook, this machine check _OS name
> > string, it's essentially obsolete.
> > 
> > Please add the following kernel parameter to /boot/grub/menu.lst:
> > 	acpi_os_name="Windows 2009"
> > 
> > Let's by-pass the _OS name check first, hope it fix this issue.
> > 
> > 
> > Thanks
> > Joey Lee
> 
> Hello,
> 
> I tried to add one of these acpi_os_name into grub kernel command line:
> 
> acpi_os_name="Windows 2009"
> acpi_os_name="Windows 2006"
> acpi_os_name="Windows 2001"
> acpi_os_name="Windows 2001 SP1"
> acpi_os_name="Windows 2001 SP2"
> 
> but brightness control (via /sys/class/backlight/acpi_video0/brightness) did 
> not worked.
> 
> -- 
> Pali Rohár
> pali.rohar@gmail.com

In DSDT, check the following 3 OS name strings, just need feed a string
not in list could be by-pass _OS check:

    Name (OSID, Package (0x03)
    {
        "Microsoft Windows",
        "Microsoft WindowsME: Millennium Edition",
        "Microsoft Windows NT"                  /* match with Linux kernel's _OS name default define */
    })

Unfortunately, just by-pass _OS check cann't fix your problem. I need
spend time to dig more detail in your DSDT.
Could you please attached your whole dmesg log that cover system boot
and press brightness control key a couple of times?


Thanks a lot!
Joey Lee