samsung: hardware: add support for adaptive backlight

Change-Id: I59b798e9cac2cf2c6efbe31736d3361f05c81398

cmhw/org/cyanogenmod/hardware/AdaptiveBacklight.java

@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2013 The CyanogenMod Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.cyanogenmod.hardware;
+
+import org.cyanogenmod.hardware.util.FileUtils;
+
+import java.io.File;
+
+/**
+ * Adaptive backlight support (this refers to technologies like NVIDIA SmartDimmer,
+ * QCOM CABL or Samsung CABC).
+ */
+public class AdaptiveBacklight {
+
+    private static String FILE_CABC = "/sys/class/lcd/panel/power_reduce";
+
+    /**
+     * Whether device supports an adaptive backlight technology.
+     *
+     * @return boolean Supported devices must return always true
+     */
+    public static boolean isSupported() {
+        File f = new File(FILE_CABC);
+
+        if(f.exists()) {
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    /**
+     * This method return the current activation status of the adaptive backlight technology.
+     *
+     * @return boolean Must be false when adaptive backlight is not supported or not activated, or
+     * the operation failed while reading the status; true in any other case.
+     */
+    public static boolean isEnabled() {
+        if (Integer.parseInt(FileUtils.readOneLine(FILE_CABC)) == 1) {
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    /**
+     * This method allows to setup adaptive backlight technology status.
+     *
+     * @param status The new adaptive backlight status
+     * @return boolean Must be false if adaptive backlight is not supported or the operation
+     * failed; true in any other case.
+     */
+    public static boolean setEnabled(boolean status) {
+        if (status == true) {
+            return FileUtils.writeLine(FILE_CABC, "1");
+        } else {
+            return FileUtils.writeLine(FILE_CABC, "0");
+        }
+    }
+}