diff -ur kde-workspace-4.9.4.org/powerdevil/daemon/backends/upower/powerdevilupowerbackend.cpp kde-workspace-4.9.4/powerdevil/daemon/backends/upower/powerdevilupowerbackend.cpp
--- kde-workspace-4.9.4.org/powerdevil/daemon/backends/upower/powerdevilupowerbackend.cpp	2012-11-30 08:24:40.000000000 +0100
+++ kde-workspace-4.9.4/powerdevil/daemon/backends/upower/powerdevilupowerbackend.cpp	2012-12-03 09:18:49.162194544 +0100
@@ -108,6 +108,7 @@
 
     if (!controls.isEmpty()) {
         m_cachedBrightness = brightness(Screen);
+        m_cachedBrightness_timer.start();
         kDebug() << "current screen brightness: " << m_cachedBrightness;
     }
 
@@ -153,6 +154,9 @@
 
 void PowerDevilUPowerBackend::brightnessKeyPressed(PowerDevil::BackendInterface::BrightnessKeyType type)
 {
+    if (m_cachedBrightness_timer.elapsed() < 100)
+        return; // two key presses delivered for single physical key press; 100ms marign
+
     BrightnessControlsList controls = brightnessControlsAvailable();
     QList<QString> screenControls = controls.keys(Screen);
 
@@ -165,14 +169,16 @@
     if (qFuzzyCompare(currentBrightness, m_cachedBrightness)) {
         float newBrightness;
         if (type == Increase) {
-            newBrightness = qMin(100.0f, currentBrightness + 10);
+            newBrightness = qMin(100.0f, currentBrightness + 6);
         } else {
-            newBrightness = qMax(0.0f, currentBrightness - 10);
+            newBrightness = qMax(0.0f, currentBrightness - 6);
         }
 
         setBrightness(newBrightness, Screen);
     } else {
         m_cachedBrightness = currentBrightness;
+        m_cachedBrightness_timer.restart();
+        onBrightnessChanged(Screen, m_cachedBrightness);
     }
 }
 
@@ -209,6 +215,10 @@
 bool PowerDevilUPowerBackend::setBrightness(float brightnessValue, PowerDevil::BackendInterface::BrightnessControlType type)
 {
     bool success = false;
+
+    if (m_cachedBrightness_timer.elapsed() < 100)
+        return success;
+
     if (type == Screen) {
         kDebug() << "set screen brightness: " << brightnessValue;
         if (m_brightnessControl->isSupported()) {
@@ -236,6 +246,7 @@
         float newBrightness = brightness(Screen);
         if (!qFuzzyCompare(newBrightness, m_cachedBrightness)) {
             m_cachedBrightness = newBrightness;
+            m_cachedBrightness_timer.restart();
             onBrightnessChanged(Screen, m_cachedBrightness);
         }
         return true;
Tylko w kde-workspace-4.9.4/powerdevil/daemon/backends/upower: powerdevilupowerbackend.cpp~
Tylko w kde-workspace-4.9.4/powerdevil/daemon/backends/upower: powerdevilupowerbackend.cpp.orig
Tylko w kde-workspace-4.9.4/powerdevil/daemon/backends/upower: powerdevilupowerbackend.cpp.rej
diff -ur kde-workspace-4.9.4.org/powerdevil/daemon/backends/upower/powerdevilupowerbackend.h kde-workspace-4.9.4/powerdevil/daemon/backends/upower/powerdevilupowerbackend.h
--- kde-workspace-4.9.4.org/powerdevil/daemon/backends/upower/powerdevilupowerbackend.h	2012-11-30 08:24:40.000000000 +0100
+++ kde-workspace-4.9.4/powerdevil/daemon/backends/upower/powerdevilupowerbackend.h	2012-12-03 08:17:04.465869449 +0100
@@ -70,6 +70,7 @@
 
     // brightness
     float m_cachedBrightness;
+    QElapsedTimer m_cachedBrightness_timer;
     XRandrBrightness         *m_brightnessControl;
     OrgFreedesktopUPowerInterface *m_upowerInterface;
     OrgFreedesktopUPowerKbdBacklightInterface *m_kbdBacklight;