I've been using Kubuntu (KDE on Ubuntu) for a couple years.  Once I
installed Kubuntu on my new Dell XPS M1330 a couple years ago, I found a
workaround to fix the double brightness issue; which was to blacklist video
module.  It worked but when I upgraded to 9.10 that no longer worked.

On Tue, Nov 3, 2009 at 11:50 AM, Mikael Gerdin <email address hidden>wrote:

> I wonder if this affects only KDE or not, Michael, are you running KDE or
> something else?
>
> On Tuesday 03 November 2009 20.38.35 Michael Rooney wrote:
> > I just want to mention that on my Dell XPS 1330 with Karmic, I do NOT
> > experience this issue at all, everything regarding brightness works as
> > expected out of the box.
> >
>
> --
> Screen brightness double level changes on Dell laptops
> https://bugs.launchpad.net/bugs/207473
> You received this bug notification because you are a direct subscriber
> of a duplicate bug.
>
> Status in The Linux Kernel: Fix Released
> Status in “hal” package in Ubuntu: Invalid
> Status in “kde-guidance” package in Ubuntu: Fix Released
> Status in “linux” package in Ubuntu: Confirmed
> Status in hal in Ubuntu Hardy: Invalid
> Status in kde-guidance in Ubuntu Hardy: Fix Released
> Status in linux in Ubuntu Hardy: Confirmed
>
> Bug description:
> Binary package hint: gnome-power-manager
>
> I have a fresh installation of Hardy with the latest updates installed on a
> Dell Inspiron 6400 laptop. The brightness settings (Fn+Up/Down) work
> although they seem to skip a level each time.
>
> '/proc/acpi/video/VID/LCD/brightness' tells me that it supports brightness
> levels 12, 24, 36, 48, 60, 72, 84 and 100. Without gnome-power-manager
> running pressing Fn+Up will transition up into each level and back down
> again smoothly.
>
> When gnome-power-manager is running increasing the brightness from 12 I can
> only get levels 36, 60, 84 and 100. Decreasing the levels from 100 I only
> get 72, 48, 24 and 12. Running gnome-power-manager with the verbose option
> shows that when I press the brightness-up button once it is recorded twice.
> I ran gnome-power-manager in a debugger thinking it was a timing issue and
> it still happened.
>
> I have included the output from pressing the brightness-up button (Fn+Up)
> once below. This only happens when gnome-power-manager is running and did
> not happen using Feisty. I have looked at the code and I cannot see why the
> button event is triggered twice, I don't have any experience of the code but
> if you can give me any ideas of where to start I can try to look into this
> myself.
>
> Thanks!
>
>
> [hal_device_condition_cb] gpm-button.c:391 (00:11:48):
> condition=ButtonPressed, details=brightness-up
> [emit_button_pressed] gpm-button.c:335 (00:11:48):       emitting
> button-pressed : brightness-up
> [button_pressed_cb] gpm-manager.c:999 (00:11:48):        Button press event
> type=brightness-up
> [button_pressed_cb] gpm-srv-screensaver.c:167 (00:11:48):        Button
> press event type=brightness-up
> [button_pressed_cb] gpm-backlight.c:563 (00:11:48):      Button press event
> type=brightness-up
> [gpm_brightness_lcd_get_hw] gpm-brightness-lcd.c:116 (00:11:48):
> GetBrightness returned level: 0
> [gpm_brightness_lcd_set_hw] gpm-brightness-lcd.c:155 (00:11:48):
> Setting 1 of 7
> [gpm_brightness_lcd_up] gpm-brightness-lcd.c:362 (00:11:48):     emitting
> brightness-changed (14)
> [brightness_changed_cb] gpm-backlight.c:755 (00:11:48):  Need to display
> backlight feedback value 14
> [gpm_feedback_display_value] gpm-feedback-widget.c:144 (00:11:48):
> Displaying 0.140000 on feedback widget
> [gpm_refcount_add] gpm-refcount.c:100 (00:11:48):        refcount now: 1
> [gpm_refcount_add] gpm-refcount.c:101 (00:11:48):        non zero, so
> sending REFCOUNT_ADDED
> [brightness_changed_cb] gpm-backlight.c:759 (00:11:48):  emitting
> brightness-changed : 14
> [button_pressed_cb] gpm-info.c:698 (00:11:48):   Button press event
> type=brightness-up
> [hal_device_condition_cb] gpm-button.c:391 (00:11:48):
> condition=ButtonPressed, details=brightness-up
> [emit_button_pressed] gpm-button.c:335 (00:11:48):       emitting
> button-pressed : brightness-up
> [button_pressed_cb] gpm-manager.c:999 (00:11:48):        Button press event
> type=brightness-up
> [button_pressed_cb] gpm-srv-screensaver.c:167 (00:11:48):        Button
> press event type=brightness-up
> [button_pressed_cb] gpm-backlight.c:563 (00:11:48):      Button press event
> type=brightness-up
> [gpm_brightness_lcd_get_hw] gpm-brightness-lcd.c:116 (00:11:48):
> GetBrightness returned level: 1
> [gpm_brightness_lcd_set_hw] gpm-brightness-lcd.c:155 (00:11:48):
> Setting 2 of 7
> [gpm_brightness_lcd_up] gpm-brightness-lcd.c:362 (00:11:48):     emitting
> brightness-changed (28)
> [brightness_changed_cb] gpm-backlight.c:755 (00:11:48):  Need to display
> backlight feedback value 28
> [gpm_feedback_display_value] gpm-feedback-widget.c:144 (00:11:48):
> Displaying 0.280000 on feedback widget
> [gpm_refcount_add] gpm-refcount.c:100 (00:11:48):        refcount now: 2
> [gpm_refcount_add] gpm-refcount.c:101 (00:11:48):        non zero, so
> sending REFCOUNT_ADDED
> [brightness_changed_cb] gpm-backlight.c:759 (00:11:48):  emitting
> brightness-changed : 28
> [button_pressed_cb] gpm-info.c:698 (00:11:48):   Button press event
> type=brightness-up
> [gpm_refcount_auto_decrement] gpm-refcount.c:77 (00:11:50):      refcount
> now: 1
> [gpm_refcount_auto_decrement] gpm-refcount.c:74 (00:11:50):      zero, so
> sending REFCOUNT_ZERO
> [gpm_feedback_close_window] gpm-feedback-widget.c:134 (00:11:50):
>  Closing feedback widget
>