When using brightness keys and backlight device's sysfs interface alternately, an incorrect input event might be generated for a brightness key press. Consider the following sequence of events: 1. Set backlight brightness to 6 using brightness keys. 2. Write 4 to /sys/class/backlight/fujitsu-laptop/brightness. 3. Press the "brightness up" key. The input event generated in this scenario would be KEY_BRIGHTNESSDOWN, because before step 3 brightness_level would still be at 6. As the new brightness level is established using GBLL, it would evaluate to 5 (SBLL/SBL2 sets it to 4 in step 2 and pressing the "brightness up" key increases it by 1). This in turn would cause acpi_fujitsu_bl_notify() to observe a 6 -> 5 change, i.e. a decrease in brightness, while screen brightness would in fact be increased. Fix this by updating brightness_level in set_lcd_level. Signed-off-by: Michał Kępień <kernel@xxxxxxxxxx> --- drivers/platform/x86/fujitsu-laptop.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c index 6d4a2a36716b..b019060d6dc4 100644 --- a/drivers/platform/x86/fujitsu-laptop.c +++ b/drivers/platform/x86/fujitsu-laptop.c @@ -384,6 +384,8 @@ static int set_lcd_level(int level) return -ENODEV; } + fujitsu_bl->brightness_level = level; + return 0; } -- 2.12.2
