Commits
Linus Torvalds committed 8ab58e8e7e0
ACPI / video: Fix backlight taking 2 steps on a brightness up/down keypress In various scenarious userspace will respond to brightness up/down keypresses by increasing/decreasing the backlight brightness itself. If the kernel then also changes the brightness this results in the brightness having changed 2 steps for a single keypress which is undesirable. See e.g. : https://bugs.launchpad.net/gnome-settings-daemon/+bug/527157 http://askubuntu.com/questions/173921/why-does-my-thinkpad-brightness-control-skip-steps This commit delays responding to brightness up/down keypresses by 100 ms and if userspace in that time responds by changing the backlight itself, cancels the kernels own handling of these keypresses, fixing the 2 steps issue. Link: http://marc.info/?l=linux-kernel&m=140535721100839&w=2 [hdegoede@redhat.com: Move the delayed_work struct into struct acpi_video_device instead of having it as a global] [hdegoede@redhat.com: Keep brightness_switch_enabled as a boolean and always delay the keypress handling] Tested-by: Hans de Goede <hdegoede@redhat.com> Tested-by: Bjørn Mork <bjorn@mork.no> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>