On Sun, Mar 31, 2013 at 08:15:14AM +0200, Danny Baumann wrote: > Artem Savkov <artem.sav...@gmail.com> schrieb: > >acpi_video_device_lcd_get_level_current() called > >acpi_video_bqc_value_to_level() > >with "*level" as a second argument, resulting in level being returned > >based on > >initial input, not current brightness, breaking backlight controls. > I don't think this change is correct. As level was passed as parameter into > the evaluation of _BQC, *level contains the AML returned brightness level > afterwards, so it's correct to use it as an input to > acpi_video_bqc_value_to_level(). Actually, the whole point of > acpi_video_device_lcd_get_level_current() is to update > device->brightness->curr, so it doesn't make sense to me to use it in that > function. > > What's the exact problem this patch tries to solve?
I'm running a -next kernel on my laptop and couple of days ago keyboard backlight controls stopped working: only 2 lower brightness levels. I've debugged it a bit and found out that acpi_video_switch_brightness() calls acpi_video_device_lcd_get_level_current() with level uninitialized and always gets lowest posible value. -- Regards, Artem -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
