> > > No, > > > For a ALS policy, user space should set a brightness level as the base > > > point, i.e. the backlight when display adjustment is 100. > > > and then uses the adjustment values gotten from this mappings to > > > calculate the actual brightness level the display should be put in. > > > > Ok, so just make the code return only the "adjustement" -- userspace > > does not really need to know "illuminance" and you can do the mapping > > in the kernel AFAICT. > > > > ALS exports > 1. the current ambient light illuminance > 2. the mappings > > Backlight device exports > 1. the brightness levels. > > User space needs to: > 1. set a brightness level as the base point > 2. read the current ambient light illuminance from ALS device > 3. read the ambient light illuminance to display adjustment mappings > 4. calculate a proper brightness level we should set. > > For example, if we set brightness 6 as the default brightness, i.e. the > brightness level when ambient light illuminance is 300. > Now we walk outdoors, and the current illuminance is 1000, > then we should set the new_brightness_level to (6 * 150%) Yes, so just export ALS exports 1. the current ambient light illuminance 2. the current mapped ambient light illuminance Backlight device exports 1. the brightness levels. User space needs to: 1. set a brightness level as the base point 2. read the current mapped ambient light illuminance from ALS device 3. calculate a proper brightness level we should set. You get a) nicer interface b) simpler userland Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
