On Mon, Dec 31, 2007 at 07:24:40PM -0200, Henrique de Moraes Holschuh wrote: > No bugs, then. It is a Lenovo BIOS issue. Which doesn't mean we can't do > anything about it (besides asking Lenovo for a fix), but I am not sure of > what. > > It is probably best if thinkpad-acpi switches the ThinkPad to ACPI > brightness mode, and report this on syslog... but I have to think about it > first, and ask around for a bit. Wouldn't it just be better to disable both the ACPI brightness altogether (for both the thinkpad-acpi and video modules), and use xbacklight instead? To quote from http://www.lesswatts.org/tips/graphics.php: All laptops have magic keys, designed to reduce or increase the brightness of the LCD panel. Unfortunately, these often use model-specific drivers that are only available for other operating systems, and while Linux supports quite a few laptop models, it doesn't support all of them. As of version 7.3 of X.org, a program called xbacklight is included. It allows users to use software to directly control the backlight of machines with integrated Intel graphics, and others. In addition, for quite a few laptops, the kernel exposes a sysfs interface to control brightness. Interestingly, in our measurements we have found that, at least on newer laptops, the kernel sysfs method (which tends to use the BIOS on the machine) seems to not control the actual backlight, but rather change the colors of the pixels on the screen to appear darker. Using darker pixels obviously doesn't save as much power as reducing the intensity of the backlight. So if you have an Intel graphics card for your thinkpad, it's not clear that any solution involving the BIOS is the right one.... - Ted ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ ibm-acpi-devel mailing list ibm-acpi-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/ibm-acpi-devel
