On Saturday, December 22, 2007 9:12 am Brice Goglin wrote: > Henrique de Moraes Holschuh wrote: > > On Sat, 15 Dec 2007, Marcus Better wrote: > >> I just tried with a new one, but the brightness is still broken. > >> It requires "native" or "combination" mode. > > > > I'd like to see X.org talking to the kernel to find out and > > coordinate which mode should be used... > > Jesse, > > Could you please have a look at > http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=448467 > and see if you can find a solution with the thinkpad guys for correct > backlight handling? Marcus tried with intel git about a week ago, it > didn't go very well.
The backlight situation is rather unfortunate. As you've already discovered, there are several different ways backlights are controlled on various platforms, and some of them are incompatible. The Intel X driver now tries to talk to the kernel drivers directly (via the /sys/class/backlight interface) starting with the thinkpad_screen driver, followed by acpi_video1 and acpi_video0. Depending on how your kernel is configured, this may work perfectly or result in the drivers fighting one another for backlight adjustments. Since on Thinkpads, the kernel method is available (either via the kernel thinkpad driver or ACPI) you should try to use that, but it may be that the acpi_video1 method is your best choice. You can try that interface by changing the order of the string array in i830_lvds.c around line 67. If you want to use one of the other methods (which may provide you with more possible backlight levels) you should unload all kernel backlight drivers prior to loading X (or disabling their backlight interfaces as in the case of the thinkpad driver); that may give you a good user experience too... Sorry if I missed anything in the initial bug report, I'm on vacation at my mother-in-law's right now, with a free wireless connection kindly provided by someone called 'jazzman' (at least according to his ESSD :). Jesse -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]