Implements Hdmi Cec keycode translater

In order to transfer some keyevent to other device
we need to have a logic to translate Android keycode
to Hdmi CEC keycode and vice versa.
HdmiCecKeyTranslater handles bidirectional keycode translation.
Basically it assumes bijection between android key code to
a pair of cec keycode and its optional param.
KeycodeEntry of HdmiCecKeycodeTranslate handles a mapping of it.

Note that all available mappings have no parameterized mapping.
If new Android keycode is defined for parameterized cec keycode,
entry should be added.

Change-Id: I287082a0a6ef5eb6f0916044b78179fe3fdfbece

1 files changed, 349 insertions, 0 deletions

diff --git a/services/core/java/com/android/server/hdmi/HdmiCecKeycodeTranslator.java b/services/core/java/com/android/server/hdmi/HdmiCecKeycodeTranslator.java
new file mode 100644
index 0000000..ebb6f50
--- /dev/null
+++ b/services/core/java/com/android/server/hdmi/HdmiCecKeycodeTranslator.java
@@ -0,0 +1,349 @@
+/*
+ * Copyright (C) 2014 The Android Open Source 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 com.android.server.hdmi;
+
+import android.view.KeyEvent;
+
+/**
+ * Helper class to translate android keycode to hdmi cec keycode and vice versa.
+ */
+public class HdmiCecKeycodeTranslator {
+    public static final int UNSUPPORTED_KEYCODE = -1;
+    public static final int NO_PARAM = -1;
+
+    // =========================================================================
+    // Hdmi CEC keycodes
+    public static final int CEC_KEYCODE_SELECT = 0x00;
+    public static final int CEC_KEYCODE_UP = 0x01;
+    public static final int CEC_KEYCODE_DOWN = 0x02;
+    public static final int CEC_KEYCODE_LEFT = 0x03;
+    public static final int CEC_KEYCODE_RIGHT = 0x04;
+    public static final int CEC_KEYCODE_RIGHT_UP = 0x05;
+    public static final int CEC_KEYCODE_RIGHT_DOWN = 0x06;
+    public static final int CEC_KEYCODE_LEFT_UP = 0x07;
+    public static final int CEC_KEYCODE_LEFT_DOWN = 0x08;
+    public static final int CEC_KEYCODE_ROOT_MENU = 0x09;
+    public static final int CEC_KEYCODE_SETUP_MENU = 0x0A;
+    public static final int CEC_KEYCODE_CONTENTS_MENU = 0x0B;
+    public static final int CEC_KEYCODE_FAVORITE_MENU = 0x0C;
+    public static final int CEC_KEYCODE_EXIT = 0x0D;
+    // RESERVED = 0x0E - 0x0F
+    public static final int CEC_KEYCODE_MEDIA_TOP_MENU = 0x10;
+    public static final int CEC_KEYCODE_MEDIA_CONTEXT_SENSITIVE_MENU = 0x11;
+    // RESERVED = 0x12 – 0x1C
+    public static final int CEC_KEYCODE_NUMBER_ENTRY_MODE = 0x1D;
+    public static final int CEC_KEYCODE_NUMBER_11 = 0x1E;
+    public static final int CEC_KEYCODE_NUMBER_12 = 0x1F;
+    public static final int CEC_KEYCODE_NUMBER_0_OR_NUMBER_10 = 0x20;
+    public static final int CEC_KEYCODE_NUMBERS_1 = 0x21;
+    public static final int CEC_KEYCODE_NUMBERS_2 = 0x22;
+    public static final int CEC_KEYCODE_NUMBERS_3 = 0x23;
+    public static final int CEC_KEYCODE_NUMBERS_4 = 0x24;
+    public static final int CEC_KEYCODE_NUMBERS_5 = 0x25;
+    public static final int CEC_KEYCODE_NUMBERS_6 = 0x26;
+    public static final int CEC_KEYCODE_NUMBERS_7 = 0x27;
+    public static final int CEC_KEYCODE_NUMBERS_8 = 0x28;
+    public static final int CEC_KEYCODE_NUMBERS_9 = 0x29;
+    public static final int CEC_KEYCODE_DOT = 0x2A;
+    public static final int CEC_KEYCODE_ENTER = 0x2B;
+    public static final int CEC_KEYCODE_CLEAR = 0x2C;
+    // RESERVED = 0x2D - 0x2E
+    public static final int CEC_KEYCODE_NEXT_FAVORITE = 0x2F;
+    public static final int CEC_KEYCODE_CHANNEL_UP = 0x30;
+    public static final int CEC_KEYCODE_CHANNEL_DOWN = 0x31;
+    public static final int CEC_KEYCODE_PREVIOUS_CHANNEL = 0x32;
+    public static final int CEC_KEYCODE_SOUND_SELECT = 0x33;
+    public static final int CEC_KEYCODE_INPUT_SELECT = 0x34;
+    public static final int CEC_KEYCODE_DISPLAY_INFORMATION = 0x35;
+    public static final int CEC_KEYCODE_HELP = 0x36;
+    public static final int CEC_KEYCODE_PAGE_UP = 0x37;
+    public static final int CEC_KEYCODE_PAGE_DOWN = 0x38;
+    // RESERVED = 0x39 - 0x3F
+    public static final int CEC_KEYCODE_POWER = 0x40;
+    public static final int CEC_KEYCODE_VOLUME_UP = 0x41;
+    public static final int CEC_KEYCODE_VOLUME_DOWN = 0x42;
+    public static final int CEC_KEYCODE_MUTE = 0x43;
+    public static final int CEC_KEYCODE_PLAY = 0x44;
+    public static final int CEC_KEYCODE_STOP = 0x45;
+    public static final int CEC_KEYCODE_PAUSE = 0x46;
+    public static final int CEC_KEYCODE_RECORD = 0x47;
+    public static final int CEC_KEYCODE_REWIND = 0x48;
+    public static final int CEC_KEYCODE_FAST_FORWARD = 0x49;
+    public static final int CEC_KEYCODE_EJECT = 0x4A;
+    public static final int CEC_KEYCODE_FORWARD = 0x4B;
+    public static final int CEC_KEYCODE_BACKWARD = 0x4C;
+    public static final int CEC_KEYCODE_STOP_RECORD = 0x4D;
+    public static final int CEC_KEYCODE_PAUSE_RECORD = 0x4E;
+    public static final int CEC_KEYCODE_RESERVED = 0x4F;
+    public static final int CEC_KEYCODE_ANGLE = 0x50;
+    public static final int CEC_KEYCODE_SUB_PICTURE = 0x51;
+    public static final int CEC_KEYCODE_VIDEO_ON_DEMAND = 0x52;
+    public static final int CEC_KEYCODE_ELECTRONIC_PROGRAM_GUIDE = 0x53;
+    public static final int CEC_KEYCODE_TIMER_PROGRAMMING = 0x54;
+    public static final int CEC_KEYCODE_INITIAL_CONFIGURATION = 0x55;
+    public static final int CEC_KEYCODE_SELECT_BROADCAST_TYPE = 0x56;
+    public static final int CEC_KEYCODE_SELECT_SOUND_PRESENTATION = 0x57;
+    // RESERVED = 0x58-0x5F
+    public static final int CEC_KEYCODE_PLAY_FUNCTION = 0x60;
+    public static final int CEC_KEYCODE_PAUSE_PLAY_FUNCTION = 0x61;
+    public static final int CEC_KEYCODE_RECORD_FUNCTION = 0x62;
+    public static final int CEC_KEYCODE_PAUSE_RECORD_FUNCTION = 0x63;
+    public static final int CEC_KEYCODE_STOP_FUNCTION = 0x64;
+    public static final int CEC_KEYCODE_MUTE_FUNCTION = 0x65;
+    public static final int CEC_KEYCODE_RESTORE_VOLUME_FUNCTION = 0x66;
+    public static final int CEC_KEYCODE_TUNE_FUNCTION = 0x67;
+    public static final int CEC_KEYCODE_SELECT_MEDIA_FUNCTION = 0x68;
+    public static final int CEC_KEYCODE_SELECT_AV_INPUT_FUNCTION = 0x69;
+    public static final int CEC_KEYCODE_SELECT_AUDIO_INPUT_FUNCTION = 0x6A;
+    public static final int CEC_KEYCODE_POWER_TOGGLE_FUNCTION = 0x6B;
+    public static final int CEC_KEYCODE_POWER_OFF_FUNCTION = 0x6C;
+    public static final int CEC_KEYCODE_POWER_ON_FUNCTION = 0x6D;
+    // RESERVED = 0x6E-0x70
+    public static final int CEC_KEYCODE_F1_BLUE = 0x71;
+    public static final int CEC_KEYCODE_F2_RED = 0x72;
+    public static final int CEC_KEYCODE_F3_GREEN = 0x73;
+    public static final int CEC_KEYCODE_F4_YELLOW = 0x74;
+    public static final int CEC_KEYCODE_F5 = 0x75;
+    public static final int CEC_KEYCODE_DATA = 0x76;
+    // RESERVED = 0x77-0xFF
+
+    // =========================================================================
+    // UI Broadcast Type
+    public static final int UI_BROADCAST_TOGGLE_ALL = 0x00;
+    public static final int UI_BROADCAST_TOGGLE_ANALOGUE_DIGITAL = 0x01;
+    public static final int UI_BROADCAST_ANALOGUE = 0x10;
+    public static final int UI_BROADCAST_ANALOGUE_TERRESTRIAL = 0x20;
+    public static final int UI_BROADCAST_ANALOGUE_CABLE = 0x30;
+    public static final int UI_BROADCAST_ANALOGUE_SATELLITE = 0x40;
+    public static final int UI_BROADCAST_DIGITAL = 0x50;
+    public static final int UI_BROADCAST_DIGITAL_TERRESTRIAL = 0x60;
+    public static final int UI_BROADCAST_DIGITAL_CABLE = 0x70;
+    public static final int UI_BROADCAST_DIGITAL_SATELLITE = 0x80;
+    public static final int UI_BROADCAST_DIGITAL_COMMNICATIONS_SATELLITE = 0x90;
+    public static final int UI_BROADCAST_DIGITAL_COMMNICATIONS_SATELLITE_2 = 0x91;
+    public static final int UI_BROADCAST_IP = 0xA0;
+
+    // =========================================================================
+    // UI Sound Presentation Control
+    public static final int UI_SOUND_PRESENTATION_SOUND_MIX_DUAL_MONO = 0x20;
+    public static final int UI_SOUND_PRESENTATION_SOUND_MIX_KARAOKE = 0x30;
+    public static final int UI_SOUND_PRESENTATION_SELECT_AUDIO_DOWN_MIX = 0x80;
+    public static final int UI_SOUND_PRESENTATION_SELECT_AUDIO_AUTO_REVERBERATION = 0x90;
+    public static final int UI_SOUND_PRESENTATION_SELECT_AUDIO_AUTO_EQUALIZER = 0xA0;
+    public static final int UI_SOUND_PRESENTATION_BASS_STEP_PLUS = 0xB1;
+    public static final int UI_SOUND_PRESENTATION_BASS_NEUTRAL = 0xB2;
+    public static final int UI_SOUND_PRESENTATION_BASS_STEP_MINUS = 0xB3;
+    public static final int UI_SOUND_PRESENTATION_TREBLE_STEP_PLUS = 0xC1;
+    public static final int UI_SOUND_PRESENTATION_TREBLE_NEUTRAL = 0xC2;
+    public static final int UI_SOUND_PRESENTATION_TREBLE_STEP_MINUS = 0xC3;
+
+    private HdmiCecKeycodeTranslator() {
+    }
+
+    /**
+     * A mapping between andorid and cec keycode.
+     *
+     * <p>Normal implementation of this looks like
+     * <pre>
+     *    new KeycodeEntry(KeyEvent.KEYCODE_DPAD_CENTER, CEC_KEYCODE_SELECT);
+     * </pre>
+     * <p>However, some keys in CEC requires additional parameter.
+     * In order to use parameterized cec key, add unique android keycode (existing or custom)
+     * corresponding to a pair of cec keycode and and its param.
+     * <pre>
+     *    new KeycodeEntry(CUSTOME_ANDORID_KEY_1, CEC_KEYCODE_SELECT_BROADCAST_TYPE,
+     *        UI_BROADCAST_TOGGLE_ALL);
+     *    new KeycodeEntry(CUSTOME_ANDORID_KEY_2, CEC_KEYCODE_SELECT_BROADCAST_TYPE,
+     *        UI_BROADCAST_ANALOGUE);
+     * </pre>
+     */
+    private static class KeycodeEntry {
+        private final int mAndroidKeycode;
+        private final int mCecKeycode;
+        private final int mParam;
+
+        private KeycodeEntry(int androidKeycode, int cecKeycode, int param) {
+            this.mAndroidKeycode = androidKeycode;
+            this.mCecKeycode = cecKeycode;
+            this.mParam = param;
+        }
+
+        private KeycodeEntry(int androidKeycode, int cecKeycode) {
+            this(androidKeycode, cecKeycode, NO_PARAM);
+        }
+
+        private byte[] toCecKeycodeIfMatched(int androidKeycode) {
+            if (mAndroidKeycode == androidKeycode) {
+                if (mParam == NO_PARAM) {
+                    return new byte[] {
+                        (byte) (mCecKeycode & 0xFF)
+                    };
+                } else {
+                    return new byte[] {
+                        (byte) (mCecKeycode & 0xFF),
+                        (byte) (mParam & 0xFF)
+                    };
+                }
+            } else {
+                return null;
+            }
+        }
+
+        private int toAndroidKeycodeIfMatched(int cecKeycode, int param) {
+            if (cecKeycode == mCecKeycode && mParam == param) {
+                return mAndroidKeycode;
+            } else {
+                return UNSUPPORTED_KEYCODE;
+            }
+        }
+    }
+
+    // Keycode entry container for all mappings.
+    // Note that order of entry is the same as above cec keycode definition.
+    private static final KeycodeEntry[] KEYCODE_ENTRIES = new KeycodeEntry[] {
+            new KeycodeEntry(KeyEvent.KEYCODE_DPAD_CENTER, CEC_KEYCODE_SELECT),
+            new KeycodeEntry(KeyEvent.KEYCODE_DPAD_UP, CEC_KEYCODE_UP),
+            new KeycodeEntry(KeyEvent.KEYCODE_DPAD_DOWN, CEC_KEYCODE_DOWN),
+            new KeycodeEntry(KeyEvent.KEYCODE_DPAD_LEFT, CEC_KEYCODE_LEFT),
+            new KeycodeEntry(KeyEvent.KEYCODE_DPAD_RIGHT, CEC_KEYCODE_RIGHT),
+            // No Android keycode defined for CEC_KEYCODE_RIGHT_UP
+            // No Android keycode defined for CEC_KEYCODE_RIGHT_DOWN
+            // No Android keycode defined for CEC_KEYCODE_LEFT_UP
+            // No Android keycode defined for CEC_KEYCODE_LEFT_DOWN
+            new KeycodeEntry(KeyEvent.KEYCODE_HOME, CEC_KEYCODE_ROOT_MENU),
+            new KeycodeEntry(KeyEvent.KEYCODE_SETTINGS, CEC_KEYCODE_SETUP_MENU),
+            new KeycodeEntry(KeyEvent.KEYCODE_MENU, CEC_KEYCODE_CONTENTS_MENU),
+            // No Android keycode defined for CEC_KEYCODE_FAVORITE_MENU
+            new KeycodeEntry(KeyEvent.KEYCODE_BACK, CEC_KEYCODE_EXIT),
+            // RESERVED
+            new KeycodeEntry(KeyEvent.KEYCODE_MEDIA_TOP_MENU, CEC_KEYCODE_MEDIA_TOP_MENU),
+            // No Android keycode defined for CEC_KEYCODE_MEDIA_CONTEXT_SENSITIVE_MENU
+            // RESERVED
+            // No Android keycode defined for CEC_KEYCODE_NUMBER_ENTRY_MODE
+            new KeycodeEntry(KeyEvent.KEYCODE_11, CEC_KEYCODE_NUMBER_11),
+            new KeycodeEntry(KeyEvent.KEYCODE_12, CEC_KEYCODE_NUMBER_12),
+            new KeycodeEntry(KeyEvent.KEYCODE_0, CEC_KEYCODE_NUMBER_0_OR_NUMBER_10),
+            new KeycodeEntry(KeyEvent.KEYCODE_1, CEC_KEYCODE_NUMBERS_1),
+            new KeycodeEntry(KeyEvent.KEYCODE_2, CEC_KEYCODE_NUMBERS_2),
+            new KeycodeEntry(KeyEvent.KEYCODE_3, CEC_KEYCODE_NUMBERS_3),
+            new KeycodeEntry(KeyEvent.KEYCODE_4, CEC_KEYCODE_NUMBERS_4),
+            new KeycodeEntry(KeyEvent.KEYCODE_5, CEC_KEYCODE_NUMBERS_5),
+            new KeycodeEntry(KeyEvent.KEYCODE_6, CEC_KEYCODE_NUMBERS_6),
+            new KeycodeEntry(KeyEvent.KEYCODE_7, CEC_KEYCODE_NUMBERS_7),
+            new KeycodeEntry(KeyEvent.KEYCODE_8, CEC_KEYCODE_NUMBERS_8),
+            new KeycodeEntry(KeyEvent.KEYCODE_9, CEC_KEYCODE_NUMBERS_9),
+            new KeycodeEntry(KeyEvent.KEYCODE_PERIOD, CEC_KEYCODE_DOT),
+            new KeycodeEntry(KeyEvent.KEYCODE_NUMPAD_ENTER, CEC_KEYCODE_ENTER),
+            new KeycodeEntry(KeyEvent.KEYCODE_CLEAR, CEC_KEYCODE_CLEAR),
+            // RESERVED
+            // No Android keycode defined for CEC_KEYCODE_NEXT_FAVORITE
+            new KeycodeEntry(KeyEvent.KEYCODE_CHANNEL_UP, CEC_KEYCODE_CHANNEL_UP),
+            new KeycodeEntry(KeyEvent.KEYCODE_CHANNEL_DOWN, CEC_KEYCODE_CHANNEL_DOWN),
+            new KeycodeEntry(KeyEvent.KEYCODE_LAST_CHANNEL, CEC_KEYCODE_PREVIOUS_CHANNEL),
+            // No Android keycode defined for CEC_KEYCODE_SOUND_SELECT
+            new KeycodeEntry(KeyEvent.KEYCODE_TV_INPUT, CEC_KEYCODE_INPUT_SELECT),
+            new KeycodeEntry(KeyEvent.KEYCODE_INFO, CEC_KEYCODE_DISPLAY_INFORMATION),
+            // No Android keycode defined for CEC_KEYCODE_HELP
+            new KeycodeEntry(KeyEvent.KEYCODE_PAGE_UP, CEC_KEYCODE_PAGE_UP),
+            new KeycodeEntry(KeyEvent.KEYCODE_PAGE_DOWN, CEC_KEYCODE_PAGE_DOWN),
+            // RESERVED
+            new KeycodeEntry(KeyEvent.KEYCODE_POWER, CEC_KEYCODE_POWER),
+            new KeycodeEntry(KeyEvent.KEYCODE_VOLUME_UP, CEC_KEYCODE_VOLUME_UP),
+            new KeycodeEntry(KeyEvent.KEYCODE_VOLUME_DOWN, CEC_KEYCODE_VOLUME_DOWN),
+            new KeycodeEntry(KeyEvent.KEYCODE_VOLUME_MUTE, CEC_KEYCODE_MUTE),
+            new KeycodeEntry(KeyEvent.KEYCODE_MEDIA_PLAY, CEC_KEYCODE_PLAY),
+            new KeycodeEntry(KeyEvent.KEYCODE_MEDIA_STOP, CEC_KEYCODE_STOP),
+            new KeycodeEntry(KeyEvent.KEYCODE_MEDIA_PAUSE, CEC_KEYCODE_PAUSE),
+            new KeycodeEntry(KeyEvent.KEYCODE_MEDIA_RECORD, CEC_KEYCODE_RECORD),
+            new KeycodeEntry(KeyEvent.KEYCODE_MEDIA_REWIND, CEC_KEYCODE_REWIND),
+            new KeycodeEntry(KeyEvent.KEYCODE_MEDIA_FAST_FORWARD, CEC_KEYCODE_FAST_FORWARD),
+            new KeycodeEntry(KeyEvent.KEYCODE_MEDIA_EJECT, CEC_KEYCODE_EJECT),
+            new KeycodeEntry(KeyEvent.KEYCODE_MEDIA_NEXT, CEC_KEYCODE_FORWARD),
+            new KeycodeEntry(KeyEvent.KEYCODE_MEDIA_PREVIOUS, CEC_KEYCODE_BACKWARD),
+            // No Android keycode defined for CEC_KEYCODE_STOP_RECORD
+            // No Android keycode defined for CEC_KEYCODE_PAUSE_RECORD
+            // No Android keycode defined for CEC_KEYCODE_RESERVED
+            // No Android keycode defined for CEC_KEYCODE_ANGLE
+            // No Android keycode defined for CEC_KEYCODE_SUB_PICTURE
+            // No Android keycode defined for CEC_KEYCODE_VIDEO_ON_DEMAND
+            new KeycodeEntry(KeyEvent.KEYCODE_GUIDE, CEC_KEYCODE_ELECTRONIC_PROGRAM_GUIDE),
+            // No Android keycode defined for CEC_KEYCODE_TIMER_PROGRAMMING
+            // No Android keycode defined for CEC_KEYCODE_INITIAL_CONFIGURATION
+            // No Android keycode defined for CEC_KEYCODE_SELECT_BROADCAST_TYPE
+            // No Android keycode defined for CEC_KEYCODE_SELECT_SOUND_PRESENTATION
+            // RESERVED
+            // The following deterministic key definitions do not need key mapping
+            // since they are supposed to be generated programmatically only.
+            // No Android keycode defined for CEC_KEYCODE_PLAY_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_PAUSE_PLAY_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_RECORD_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_PAUSE_RECORD_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_STOP_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_MUTE_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_RESTORE_VOLUME_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_TUNE_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_SELECT_MEDIA_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_SELECT_AV_INPUT_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_SELECT_AUDIO_INPUT_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_POWER_TOGGLE_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_POWER_OFF_FUNCTION
+            // No Android keycode defined for CEC_KEYCODE_POWER_ON_FUNCTION
+            // RESERVED
+            new KeycodeEntry(KeyEvent.KEYCODE_PROG_BLUE, CEC_KEYCODE_F1_BLUE),
+            new KeycodeEntry(KeyEvent.KEYCODE_PROG_RED, CEC_KEYCODE_F2_RED),
+            new KeycodeEntry(KeyEvent.KEYCODE_PROG_GREEN, CEC_KEYCODE_F3_GREEN),
+            new KeycodeEntry(KeyEvent.KEYCODE_PROG_YELLOW, CEC_KEYCODE_F4_YELLOW),
+            new KeycodeEntry(KeyEvent.KEYCODE_F5, CEC_KEYCODE_F5),
+            new KeycodeEntry(KeyEvent.KEYCODE_TV_DATA_SERVICE, CEC_KEYCODE_DATA),
+            // RESERVED
+            // Add a new key mapping here if new keycode is introduced.
+    };
+
+    /**
+     * Translate Android keycode to Hdmi Cec keycode.
+     *
+     * @param keycode Android keycode. For details, refer {@link KeyEvent}
+     * @return array of byte which contains cec keycode and param if it has;
+     *         return null if failed to find matched cec keycode
+     */
+    static byte[] androidKeyToCecKey(int keycode) {
+        for (int i = 0; i < KEYCODE_ENTRIES.length; ++i) {
+            byte[] cecKeycode = KEYCODE_ENTRIES[i].toCecKeycodeIfMatched(keycode);
+            if (cecKeycode != null) {
+                return cecKeycode;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Translate Hdmi CEC keycode to Android keycode.
+     *
+     * @param keycode Cec keycode. If has no param, put {@link #NO_PARAM}
+     * @return cec keycode corresponding to the given android keycode.
+     *         If finds no matched keycode, return {@link #UNSUPPORTED_KEYCODE}
+     */
+    static int cecKeyToAndroidKey(int keycode, int param) {
+        for (int i = 0; i < KEYCODE_ENTRIES.length; ++i) {
+            int androidKey = KEYCODE_ENTRIES[i].toAndroidKeycodeIfMatched(keycode, param);
+            if (androidKey != UNSUPPORTED_KEYCODE) {
+                return androidKey;
+            }
+        }
+        return UNSUPPORTED_KEYCODE;
+    }
+}