SendKeyAction.java revision 8566be3c51d97d9a4b62bfec52b1c88ade65dd43
1/* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16package com.android.server.hdmi; 17 18import static com.android.server.hdmi.HdmiConfig.IRT_MS; 19 20import android.util.Slog; 21import android.view.KeyEvent; 22 23/** 24 * Feature action that transmits remote control key command (User Control Press/ 25 * User Control Release) to CEC bus. 26 * 27 * <p>This action is created when a new key event is passed to CEC service. It optionally 28 * does key repeat (a.k.a. press-and-hold) operation until it receives a key release event. 29 * If another key press event is received before the key in use is released, CEC service 30 * does not create a new action but recycles the current one by updating the key used 31 * for press-and-hold operation. 32 * 33 * <p>Package-private, accessed by {@link HdmiControlService} only. 34 */ 35final class SendKeyAction extends HdmiCecFeatureAction { 36 private static final String TAG = "SendKeyAction"; 37 38 // Amount of time this action waits for a new release key input event. When timed out, 39 // the action sends out UCR and finishes its lifecycle. Used to deal with missing key release 40 // event, which can lead the device on the receiving end to generating unintended key repeats. 41 private static final int AWAIT_RELEASE_KEY_MS = 1000; 42 43 // State in which the action is at work. The state is set in {@link #start()} and 44 // persists throughout the process till it is set back to {@code STATE_NONE} at the end. 45 private static final int STATE_PROCESSING_KEYCODE = 1; 46 47 // Logical address of the device to which the UCP/UCP commands are sent. 48 private final int mTargetAddress; 49 50 // The key code of the last key press event the action is passed via processKeyEvent. 51 private int mLastKeycode; 52 53 // The time stamp when the last CEC key command was sent. Used to determine the press-and-hold 54 // operation. 55 private long mLastSendKeyTime; 56 57 /** 58 * Constructor. 59 * 60 * @param source {@link HdmiCecLocalDevice} instance 61 * @param targetAddress logical address of the device to send the keys to 62 * @param keycode remote control key code as defined in {@link KeyEvent} 63 */ 64 SendKeyAction(HdmiCecLocalDevice source, int targetAddress, int keycode) { 65 super(source); 66 mTargetAddress = targetAddress; 67 mLastKeycode = keycode; 68 } 69 70 @Override 71 public boolean start() { 72 sendKeyDown(mLastKeycode); 73 mLastSendKeyTime = getCurrentTime(); 74 // finish action for non-repeatable key. 75 if (!HdmiCecKeycode.isRepeatableKey(mLastKeycode)) { 76 sendKeyUp(); 77 finish(); 78 return true; 79 } 80 mState = STATE_PROCESSING_KEYCODE; 81 addTimer(mState, AWAIT_RELEASE_KEY_MS); 82 return true; 83 } 84 85 private long getCurrentTime() { 86 return System.currentTimeMillis(); 87 } 88 89 /** 90 * Called when a key event should be handled for the action. 91 * 92 * @param keycode key code of {@link KeyEvent} object 93 * @param isPressed true if the key event is of {@link KeyEvent#ACTION_DOWN} 94 */ 95 void processKeyEvent(int keycode, boolean isPressed) { 96 if (mState != STATE_PROCESSING_KEYCODE) { 97 Slog.w(TAG, "Not in a valid state"); 98 return; 99 } 100 if (isPressed) { 101 // A new key press event that comes in with a key code different from the last 102 // one becomes a new key code to be used for press-and-hold operation. 103 if (keycode != mLastKeycode) { 104 sendKeyDown(keycode); 105 mLastSendKeyTime = getCurrentTime(); 106 if (!HdmiCecKeycode.isRepeatableKey(keycode)) { 107 sendKeyUp(); 108 finish(); 109 return; 110 } 111 } else { 112 // Press-and-hold key transmission takes place if Android key inputs are 113 // repeatedly coming in and more than IRT_MS has passed since the last 114 // press-and-hold key transmission. 115 if (getCurrentTime() - mLastSendKeyTime >= IRT_MS) { 116 sendKeyDown(keycode); 117 mLastSendKeyTime = getCurrentTime(); 118 } 119 } 120 mActionTimer.clearTimerMessage(); 121 addTimer(mState, AWAIT_RELEASE_KEY_MS); 122 mLastKeycode = keycode; 123 } else { 124 // Key release event indicates that the action shall be finished. Send UCR 125 // command and terminate the action. Other release events are ignored. 126 if (keycode == mLastKeycode) { 127 sendKeyUp(); 128 finish(); 129 } 130 } 131 } 132 133 private void sendKeyDown(int keycode) { 134 byte[] cecKeycodeAndParams = HdmiCecKeycode.androidKeyToCecKey(keycode); 135 if (cecKeycodeAndParams == null) { 136 return; 137 } 138 sendCommand(HdmiCecMessageBuilder.buildUserControlPressed(getSourceAddress(), 139 mTargetAddress, cecKeycodeAndParams)); 140 } 141 142 private void sendKeyUp() { 143 sendCommand(HdmiCecMessageBuilder.buildUserControlReleased(getSourceAddress(), 144 mTargetAddress)); 145 } 146 147 @Override 148 public boolean processCommand(HdmiCecMessage cmd) { 149 // Send key action doesn't need any incoming CEC command, hence does not consume it. 150 return false; 151 } 152 153 @Override 154 public void handleTimerEvent(int state) { 155 // Timeout on waiting for the release key event. Send UCR and quit the action. 156 if (mState != STATE_PROCESSING_KEYCODE) { 157 Slog.w(TAG, "Not in a valid state"); 158 return; 159 } 160 sendKeyUp(); 161 finish(); 162 } 163} 164