GNOME Bugzilla – Bug 566095
After going onto battery, reduces backlight level until screen is blank
Last modified: 2009-03-04 15:33:02 UTC
Please describe the problem: If I remove the power lead from my laptop, gnome-power-manager starts reducing the backlight level until the screen is off over the course of a few minutes. If I try to reset the level with 'xbacklight -set 100' then g-p-m immediately overrides it, and the screen continues on its way to darkness. While this happens, g-p-m does not respond to any other events, such as the suspend button or the backlight brightness keys being pressed. Steps to reproduce: 1. Unplug power cord Actual results: Screen goes dark after a few minutes Expected results: Nothing Does this happen every time? Yes Other information: Only started happening with 2.24. Here's the output of running gnome-power-manager --verbose --no-daemon while unplugging my laptop, and a backtrace from gdb: TI:00:51:13 TH:0x24448c0 FI:gpm-array.c FN:gpm_array_append,141 - adding to 0x269ef70, x=45, y=100, data=65280 TI:00:51:13 TH:0x24448c0 FI:gpm-array.c FN:gpm_array_append,141 - adding to 0x269f100, x=45, y=12526, data=65280 TI:00:51:17 TH:0x24448c0 FI:gpm-manager.c FN:ac_adapter_changed_cb,1028 - Setting on-ac: 0 TI:00:51:17 TH:0x24448c0 FI:gpm-idle.c FN:gpm_idle_set_system_timeout,287 - Setting system idle timeout: 60 TI:00:51:17 TH:0x24448c0 FI:gpm-manager.c FN:ac_adapter_changed_cb,1032 - emitting on-ac-changed : 0 [New Thread 0x41075950 (LWP 24122)] TI:00:51:17 TH:0x24448c0 FI:gpm-screensaver.c FN:gpm_screensaver_add_throttle,318 - adding throttle reason: 'On battery power': id 1180579573 TI:00:51:17 TH:0x24448c0 FI:gpm-screensaver.c FN:gpm_screensaver_poke,410 - poke TI:00:51:17 TH:0x24448c0 FI:gpm-backlight.c FN:gpm_backlight_brightness_evaluate_and_set,379 - 1. main brightness 1.000000 TI:00:51:17 TH:0x24448c0 FI:gpm-backlight.c FN:gpm_backlight_brightness_evaluate_and_set,397 - 2. battery scale 0.500000, brightness 0.500000 TI:00:51:17 TH:0x24448c0 FI:gpm-backlight.c FN:gpm_backlight_brightness_evaluate_and_set,416 - 3. idle scale 1.000000, brightness 0.500000 TI:00:51:17 TH:0x24448c0 FI:gpm-backlight.c FN:gpm_backlight_brightness_evaluate_and_set,436 - 4. ambient scale 1.000000, brightness 0.500000 TI:00:51:17 TH:0x24448c0 FI:gpm-brightness.c FN:gpm_brightness_trust_cache,102 - using cache for value 100 (probably okay) TI:00:51:17 TH:0x24448c0 FI:gpm-feedback-widget.c FN:gpm_feedback_display_value,140 - Displaying 0.500000 on feedback widget TI:00:51:17 TH:0x24448c0 FI:gpm-refcount.c FN:gpm_refcount_add,100 - refcount now: 1 TI:00:51:17 TH:0x24448c0 FI:gpm-refcount.c FN:gpm_refcount_add,101 - non zero, so sending REFCOUNT_ADDED TI:00:51:17 TH:0x24448c0 FI:gpm-brightness.c FN:gpm_brightness_trust_cache,102 - using cache for value 100 (probably okay) TI:00:51:17 TH:0x24448c0 FI:gpm-brightness-xrandr.c FN:gpm_brightness_xrandr_foreach_screen,414 - using resource 0x26464f0 TI:00:51:17 TH:0x24448c0 FI:gpm-brightness-xrandr.c FN:gpm_brightness_xrandr_foreach_resource,375 - resource 1 of 2 TI:00:51:17 TH:0x24448c0 FI:gpm-brightness-xrandr.c FN:gpm_brightness_xrandr_foreach_resource,375 - resource 2 of 2 TI:00:51:17 TH:0x24448c0 FI:gpm-brightness-xrandr.c FN:gpm_brightness_xrandr_output_set,322 - percent=50, absolute=12382 TI:00:51:17 TH:0x24448c0 FI:gpm-brightness-xrandr.c FN:gpm_brightness_xrandr_output_set,324 - hard value=24765, min=0, max=24765 [New Thread 0x41876950 (LWP 24125)] [New Thread 0x42077950 (LWP 24126)] [New Thread 0x42878950 (LWP 24127)] [New Thread 0x43079950 (LWP 24128)] [Thread 0x42878950 (LWP 24127) exited] [Thread 0x43079950 (LWP 24128) exited] [Thread 0x42077950 (LWP 24126) exited] [New Thread 0x42077950 (LWP 24129)] [New Thread 0x43079950 (LWP 24130)] [Thread 0x42077950 (LWP 24129) exited] [Thread 0x43079950 (LWP 24130) exited] [New Thread 0x43079950 (LWP 24132)] [New Thread 0x42077950 (LWP 24133)] [New Thread 0x42878950 (LWP 24134)] [Thread 0x42878950 (LWP 24134) exited] ^C Program received signal SIGINT, Interrupt. 0x00007f41fb271ce2 in select () from /lib/libc.so.6 (gdb) where
+ Trace 211177
[ forwarded from http://bugs.debian.org/510268 ]
If I disable 'On Battery Power' -> 'Reduce backlight brightness' then this does not happen, phew :)
2009-01-02 Richard Hughes <richard@hughsie.com> * src/gpm-brightness-xrandr.c: (gpm_brightness_xrandr_output_set): Don't step through each brightness state when we fade modes, some devices using XRandR have an insane number of steps. Use the step value we calculated for the _up and _down logic. Fixes #566095
*** Bug 571807 has been marked as a duplicate of this bug. ***
This problem has been fixed in our software repository. The fix will go into the next software release. Thank you for your bug report.