[ltp] Re: Re: T61 brightness/volume

[Marcus Better]

Hi,

Yves-Alexis Perez wrote:
> echo 10 > /sys/class/backlight/acpi_video1/brightness

I have a new Intel-based T61 and the brightness keys don't work. Surprise,
surprise :) I'm running mainline kernel 2.6.25 (x86_64), Debian with X.org
7.3 and KDE 4, xserver-xorg-video-intel 2:2.3.0-1.

I can control brightness using xbacklight. The above command does set the
brightness, but it is promptly reset back to the previous setting when I
press any key - very strange.

The Fn-Home and Fn-End keys seem to generate two press/release input event
pairs on each press. Here I pressed and released them once each:

KeyPress event, serial 31, synthetic NO, window 0x4600001,
    root 0x77, subw 0x0, time 29953307, (-721,-516), root:(1656,269),
    state 0x0, keycode 212 (keysym 0x0, NoSymbol), same_screen YES,  
    XLookupString gives 0 bytes:                                     
    XmbLookupString gives 0 bytes:                                   
    XFilterEvent returns: False                                      

KeyRelease event, serial 31, synthetic NO, window 0x4600001,
    root 0x77, subw 0x0, time 29953307, (-721,-516), root:(1656,269),
    state 0x0, keycode 212 (keysym 0x0, NoSymbol), same_screen YES,  
    XLookupString gives 0 bytes:                                     
    XFilterEvent returns: False                                      

KeyPress event, serial 31, synthetic NO, window 0x4600001,
    root 0x77, subw 0x0, time 29954214, (-721,-516), root:(1656,269),
    state 0x0, keycode 212 (keysym 0x0, NoSymbol), same_screen YES,  
    XLookupString gives 0 bytes:                                     
    XmbLookupString gives 0 bytes:                                   
    XFilterEvent returns: False                                      

KeyRelease event, serial 31, synthetic NO, window 0x4600001,
    root 0x77, subw 0x0, time 29954214, (-721,-516), root:(1656,269),
    state 0x0, keycode 212 (keysym 0x0, NoSymbol), same_screen YES,  
    XLookupString gives 0 bytes:                                     
    XFilterEvent returns: False

KeyPress event, serial 31, synthetic NO, window 0x4600001,
    root 0x77, subw 0x0, time 29955755, (-721,-516), root:(1656,269),
    state 0x0, keycode 101 (keysym 0x0, NoSymbol), same_screen YES,
    XLookupString gives 0 bytes:
    XmbLookupString gives 0 bytes:
    XFilterEvent returns: False

KeyRelease event, serial 31, synthetic NO, window 0x4600001,
    root 0x77, subw 0x0, time 29955755, (-721,-516), root:(1656,269),
    state 0x0, keycode 101 (keysym 0x0, NoSymbol), same_screen YES,
    XLookupString gives 0 bytes:
    XFilterEvent returns: False

KeyPress event, serial 31, synthetic NO, window 0x4600001,
    root 0x77, subw 0x0, time 29956661, (-721,-516), root:(1656,269),
    state 0x0, keycode 101 (keysym 0x0, NoSymbol), same_screen YES,
    XLookupString gives 0 bytes:
    XmbLookupString gives 0 bytes:
    XFilterEvent returns: False

KeyRelease event, serial 31, synthetic NO, window 0x4600001,
    root 0x77, subw 0x0, time 29956661, (-721,-516), root:(1656,269),
    state 0x0, keycode 101 (keysym 0x0, NoSymbol), same_screen YES,
    XLookupString gives 0 bytes:
    XFilterEvent returns: False

~# dmesg|grep think
thinkpad_acpi: ThinkPad ACPI Extras v0.19
thinkpad_acpi: http://ibm-acpi.sf.net/
thinkpad_acpi: ThinkPad BIOS 7LETB0WW (2.10 ), EC 7KHT24WW-1.08
thinkpad_acpi: Lenovo ThinkPad T61
thinkpad_acpi: radio switch found; radios are enabled
thinkpad_acpi: standard ACPI backlight interface available, not loading
native one...

> xrandr --output LVDS --set BACKLIGHT_CONTROL legacy

This option does not fix the Fn-Home/End behaviour.

I didn't try the brightness_enable parameter as I understand that the ACPI
video driver should handle brightness.

Any ideas?

Cheers,

Marcus