Switch from uevent model to /dev/input/event.

Headsets are now detected from calls coming in from the input switch
subsystem if a config.xml value is set to true.

Bug: 6548391.

Change-Id: I79259d2742e157b106a746474f32ffd1c171ddf3
diff --git a/services/java/com/android/server/WiredAccessoryManager.java b/services/java/com/android/server/WiredAccessoryManager.java
new file mode 100644
index 0000000..63e8895
--- /dev/null
+++ b/services/java/com/android/server/WiredAccessoryManager.java
@@ -0,0 +1,432 @@
+/*
+ * Copyright (C) 2008 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;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.Handler;
+import android.os.Looper;
+import android.os.Message;
+import android.os.PowerManager;
+import android.os.PowerManager.WakeLock;
+import android.os.UEventObserver;
+import android.util.Slog;
+import android.media.AudioManager;
+import android.util.Log;
+import android.view.InputDevice;
+
+import com.android.internal.R;
+import com.android.server.input.InputManagerService;
+import com.android.server.input.InputManagerService.WiredAccessoryCallbacks;
+import static com.android.server.input.InputManagerService.SW_HEADPHONE_INSERT;
+import static com.android.server.input.InputManagerService.SW_MICROPHONE_INSERT;
+import static com.android.server.input.InputManagerService.SW_HEADPHONE_INSERT_BIT;
+import static com.android.server.input.InputManagerService.SW_MICROPHONE_INSERT_BIT;
+
+import java.io.File;
+import java.io.FileReader;
+import java.io.FileNotFoundException;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * <p>WiredAccessoryManager monitors for a wired headset on the main board or dock using
+ * both the InputManagerService notifyWiredAccessoryChanged interface and the UEventObserver
+ * subsystem.
+ */
+final class WiredAccessoryManager implements WiredAccessoryCallbacks {
+    private static final String TAG = WiredAccessoryManager.class.getSimpleName();
+    private static final boolean LOG = true;
+
+    private static final int BIT_HEADSET = (1 << 0);
+    private static final int BIT_HEADSET_NO_MIC = (1 << 1);
+    private static final int BIT_USB_HEADSET_ANLG = (1 << 2);
+    private static final int BIT_USB_HEADSET_DGTL = (1 << 3);
+    private static final int BIT_HDMI_AUDIO = (1 << 4);
+    private static final int SUPPORTED_HEADSETS = (BIT_HEADSET|BIT_HEADSET_NO_MIC|
+                                                   BIT_USB_HEADSET_ANLG|BIT_USB_HEADSET_DGTL|
+                                                   BIT_HDMI_AUDIO);
+
+    private static final String NAME_H2W = "h2w";
+    private static final String NAME_USB_AUDIO = "usb_audio";
+    private static final String NAME_HDMI_AUDIO = "hdmi_audio";
+    private static final String NAME_HDMI = "hdmi";
+
+    private static final int MSG_NEW_DEVICE_STATE = 1;
+
+    private final Object mLock = new Object();
+
+    private final WakeLock mWakeLock;  // held while there is a pending route change
+    private final AudioManager mAudioManager;
+
+    private int mHeadsetState;
+
+    private int mSwitchValues;
+
+    private final WiredAccessoryObserver mObserver;
+    private final InputManagerService mInputManager;
+
+    private final boolean mUseDevInputEventForAudioJack;
+
+    public WiredAccessoryManager(Context context, InputManagerService inputManager) {
+        PowerManager pm = (PowerManager)context.getSystemService(Context.POWER_SERVICE);
+        mWakeLock = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "WiredAccessoryManager");
+        mWakeLock.setReferenceCounted(false);
+        mAudioManager = (AudioManager)context.getSystemService(Context.AUDIO_SERVICE);
+        mInputManager = inputManager;
+
+        mUseDevInputEventForAudioJack =
+                context.getResources().getBoolean(R.bool.config_useDevInputEventForAudioJack);
+
+        mObserver = new WiredAccessoryObserver();
+
+        context.registerReceiver(new BroadcastReceiver() {
+                    @Override
+                    public void onReceive(Context ctx, Intent intent) {
+                        bootCompleted();
+                    }
+                },
+                new IntentFilter(Intent.ACTION_BOOT_COMPLETED), null, null);
+    }
+
+    private void bootCompleted() {
+        if (mUseDevInputEventForAudioJack) {
+            int switchValues = 0;
+            if (mInputManager.getSwitchState(-1, InputDevice.SOURCE_ANY, SW_HEADPHONE_INSERT) == 1) {
+                switchValues |= SW_HEADPHONE_INSERT_BIT;
+            }
+            if (mInputManager.getSwitchState(-1, InputDevice.SOURCE_ANY, SW_MICROPHONE_INSERT) == 1) {
+                switchValues |= SW_MICROPHONE_INSERT_BIT;
+            }
+            notifyWiredAccessoryChanged(0, switchValues,
+                    SW_HEADPHONE_INSERT_BIT | SW_MICROPHONE_INSERT_BIT);
+        }
+
+        mObserver.init();
+    }
+
+    @Override
+    public void notifyWiredAccessoryChanged(long whenNanos, int switchValues, int switchMask) {
+        if (LOG) Slog.v(TAG, "notifyWiredAccessoryChanged: when=" + whenNanos
+                + " bits=" + switchCodeToString(switchValues, switchMask)
+                + " mask=" + Integer.toHexString(switchMask));
+
+        synchronized (mLock) {
+            int headset;
+            mSwitchValues = (mSwitchValues & ~switchMask) | switchValues;
+            switch (mSwitchValues & (SW_HEADPHONE_INSERT_BIT | SW_MICROPHONE_INSERT_BIT)) {
+                case 0:
+                    headset = 0;
+                    break;
+
+                case SW_HEADPHONE_INSERT_BIT:
+                    headset = BIT_HEADSET_NO_MIC;
+                    break;
+
+                case SW_HEADPHONE_INSERT_BIT | SW_MICROPHONE_INSERT_BIT:
+                    headset = BIT_HEADSET;
+                    break;
+
+                case SW_MICROPHONE_INSERT_BIT:
+                    headset = BIT_HEADSET;
+                    break;
+
+                default:
+                    headset = 0;
+                    break;
+            }
+
+            updateLocked(NAME_H2W, headset);
+        }
+    }
+
+    /**
+     * Compare the existing headset state with the new state and pass along accordingly. Note
+     * that this only supports a single headset at a time. Inserting both a usb and jacked headset
+     * results in support for the last one plugged in. Similarly, unplugging either is seen as
+     * unplugging all.
+     *
+     * @param newName One of the NAME_xxx variables defined above.
+     * @param newState 0 or one of the BIT_xxx variables defined above.
+     */
+    private void updateLocked(String newName, int newState) {
+        // Retain only relevant bits
+        int headsetState = newState & SUPPORTED_HEADSETS;
+        int usb_headset_anlg = headsetState & BIT_USB_HEADSET_ANLG;
+        int usb_headset_dgtl = headsetState & BIT_USB_HEADSET_DGTL;
+        int h2w_headset = headsetState & (BIT_HEADSET | BIT_HEADSET_NO_MIC);
+        boolean h2wStateChange = true;
+        boolean usbStateChange = true;
+        if (LOG) Slog.v(TAG, "newName=" + newName
+                + " newState=" + newState
+                + " headsetState=" + headsetState
+                + " prev headsetState=" + mHeadsetState);
+
+        if (mHeadsetState == headsetState) {
+            Log.e(TAG, "No state change.");
+            return;
+        }
+
+        // reject all suspect transitions: only accept state changes from:
+        // - a: 0 headset to 1 headset
+        // - b: 1 headset to 0 headset
+        if (h2w_headset == (BIT_HEADSET | BIT_HEADSET_NO_MIC)) {
+            Log.e(TAG, "Invalid combination, unsetting h2w flag");
+            h2wStateChange = false;
+        }
+        // - c: 0 usb headset to 1 usb headset
+        // - d: 1 usb headset to 0 usb headset
+        if (usb_headset_anlg == BIT_USB_HEADSET_ANLG && usb_headset_dgtl == BIT_USB_HEADSET_DGTL) {
+            Log.e(TAG, "Invalid combination, unsetting usb flag");
+            usbStateChange = false;
+        }
+        if (!h2wStateChange && !usbStateChange) {
+            Log.e(TAG, "invalid transition, returning ...");
+            return;
+        }
+
+        mWakeLock.acquire();
+
+        Message msg = mHandler.obtainMessage(MSG_NEW_DEVICE_STATE, headsetState,
+                mHeadsetState, newName);
+        mHandler.sendMessage(msg);
+
+        mHeadsetState = headsetState;
+    }
+
+    private final Handler mHandler = new Handler(Looper.myLooper(), null, true) {
+        @Override
+        public void handleMessage(Message msg) {
+            switch (msg.what) {
+                case MSG_NEW_DEVICE_STATE:
+                    setDevicesState(msg.arg1, msg.arg2, (String)msg.obj);
+                    mWakeLock.release();
+            }
+        }
+    };
+
+    private void setDevicesState(
+            int headsetState, int prevHeadsetState, String headsetName) {
+        synchronized (mLock) {
+            int allHeadsets = SUPPORTED_HEADSETS;
+            for (int curHeadset = 1; allHeadsets != 0; curHeadset <<= 1) {
+                if ((curHeadset & allHeadsets) != 0) {
+                    setDeviceStateLocked(curHeadset, headsetState, prevHeadsetState, headsetName);
+                    allHeadsets &= ~curHeadset;
+                }
+            }
+        }
+    }
+
+    private void setDeviceStateLocked(int headset,
+            int headsetState, int prevHeadsetState, String headsetName) {
+        if ((headsetState & headset) != (prevHeadsetState & headset)) {
+            int device;
+            int state;
+
+            if ((headsetState & headset) != 0) {
+                state = 1;
+            } else {
+                state = 0;
+            }
+
+            if (headset == BIT_HEADSET) {
+                device = AudioManager.DEVICE_OUT_WIRED_HEADSET;
+            } else if (headset == BIT_HEADSET_NO_MIC){
+                device = AudioManager.DEVICE_OUT_WIRED_HEADPHONE;
+            } else if (headset == BIT_USB_HEADSET_ANLG) {
+                device = AudioManager.DEVICE_OUT_ANLG_DOCK_HEADSET;
+            } else if (headset == BIT_USB_HEADSET_DGTL) {
+                device = AudioManager.DEVICE_OUT_DGTL_DOCK_HEADSET;
+            } else if (headset == BIT_HDMI_AUDIO) {
+                device = AudioManager.DEVICE_OUT_AUX_DIGITAL;
+            } else {
+                Slog.e(TAG, "setDeviceState() invalid headset type: "+headset);
+                return;
+            }
+
+            if (LOG)
+                Slog.v(TAG, "device "+headsetName+((state == 1) ? " connected" : " disconnected"));
+
+            mAudioManager.setWiredDeviceConnectionState(device, state, headsetName);
+        }
+    }
+
+    private String switchCodeToString(int switchValues, int switchMask) {
+        StringBuffer sb = new StringBuffer();
+        if ((switchMask & SW_HEADPHONE_INSERT_BIT) != 0 &&
+                (switchValues & SW_HEADPHONE_INSERT_BIT) != 0) {
+            sb.append("SW_HEADPHONE_INSERT ");
+        }
+        if ((switchMask & SW_MICROPHONE_INSERT_BIT) != 0 &&
+                (switchValues & SW_MICROPHONE_INSERT_BIT) != 0) {
+            sb.append("SW_MICROPHONE_INSERT");
+        }
+        return sb.toString();
+    }
+
+    class WiredAccessoryObserver extends UEventObserver {
+        private final List<UEventInfo> mUEventInfo;
+
+        public WiredAccessoryObserver() {
+            mUEventInfo = makeObservedUEventList();
+        }
+
+        void init() {
+            synchronized (mLock) {
+                if (LOG) Slog.v(TAG, "init()");
+                char[] buffer = new char[1024];
+
+                for (int i = 0; i < mUEventInfo.size(); ++i) {
+                    UEventInfo uei = mUEventInfo.get(i);
+                    try {
+                        int curState;
+                        FileReader file = new FileReader(uei.getSwitchStatePath());
+                        int len = file.read(buffer, 0, 1024);
+                        file.close();
+                        curState = Integer.valueOf((new String(buffer, 0, len)).trim());
+
+                        if (curState > 0) {
+                            updateStateLocked(uei.getDevPath(), uei.getDevName(), curState);
+                        }
+                    } catch (FileNotFoundException e) {
+                        Slog.w(TAG, uei.getSwitchStatePath() +
+                                " not found while attempting to determine initial switch state");
+                    } catch (Exception e) {
+                        Slog.e(TAG, "" , e);
+                    }
+                }
+            }
+
+            // At any given time accessories could be inserted
+            // one on the board, one on the dock and one on HDMI:
+            // observe three UEVENTs
+            for (int i = 0; i < mUEventInfo.size(); ++i) {
+                UEventInfo uei = mUEventInfo.get(i);
+                startObserving("DEVPATH="+uei.getDevPath());
+            }
+        }
+
+        private List<UEventInfo> makeObservedUEventList() {
+            List<UEventInfo> retVal = new ArrayList<UEventInfo>();
+            UEventInfo uei;
+
+            // Monitor h2w
+            if (!mUseDevInputEventForAudioJack) {
+                uei = new UEventInfo(NAME_H2W, BIT_HEADSET, BIT_HEADSET_NO_MIC);
+                if (uei.checkSwitchExists()) {
+                    retVal.add(uei);
+                } else {
+                    Slog.w(TAG, "This kernel does not have wired headset support");
+                }
+            }
+
+            // Monitor USB
+            uei = new UEventInfo(NAME_USB_AUDIO, BIT_USB_HEADSET_ANLG, BIT_USB_HEADSET_DGTL);
+            if (uei.checkSwitchExists()) {
+                retVal.add(uei);
+            } else {
+                Slog.w(TAG, "This kernel does not have usb audio support");
+            }
+
+            // Monitor HDMI
+            //
+            // If the kernel has support for the "hdmi_audio" switch, use that.  It will be
+            // signalled only when the HDMI driver has a video mode configured, and the downstream
+            // sink indicates support for audio in its EDID.
+            //
+            // If the kernel does not have an "hdmi_audio" switch, just fall back on the older
+            // "hdmi" switch instead.
+            uei = new UEventInfo(NAME_HDMI_AUDIO, BIT_HDMI_AUDIO, 0);
+            if (uei.checkSwitchExists()) {
+                retVal.add(uei);
+            } else {
+                uei = new UEventInfo(NAME_HDMI, BIT_HDMI_AUDIO, 0);
+                if (uei.checkSwitchExists()) {
+                    retVal.add(uei);
+                } else {
+                    Slog.w(TAG, "This kernel does not have HDMI audio support");
+                }
+            }
+
+            return retVal;
+        }
+
+        @Override
+        public void onUEvent(UEventObserver.UEvent event) {
+            if (LOG) Slog.v(TAG, "Headset UEVENT: " + event.toString());
+
+            try {
+                String devPath = event.get("DEVPATH");
+                String name = event.get("SWITCH_NAME");
+                int state = Integer.parseInt(event.get("SWITCH_STATE"));
+                synchronized (mLock) {
+                    updateStateLocked(devPath, name, state);
+                }
+            } catch (NumberFormatException e) {
+                Slog.e(TAG, "Could not parse switch state from event " + event);
+            }
+        }
+
+        private void updateStateLocked(String devPath, String name, int state) {
+            for (int i = 0; i < mUEventInfo.size(); ++i) {
+                UEventInfo uei = mUEventInfo.get(i);
+                if (devPath.equals(uei.getDevPath())) {
+                    updateLocked(name, uei.computeNewHeadsetState(mHeadsetState, state));
+                    return;
+                }
+            }
+        }
+
+        private final class UEventInfo {
+            private final String mDevName;
+            private final int mState1Bits;
+            private final int mState2Bits;
+
+            public UEventInfo(String devName, int state1Bits, int state2Bits) {
+                mDevName = devName;
+                mState1Bits = state1Bits;
+                mState2Bits = state2Bits;
+            }
+
+            public String getDevName() { return mDevName; }
+
+            public String getDevPath() {
+                return String.format("/devices/virtual/switch/%s", mDevName);
+            }
+
+            public String getSwitchStatePath() {
+                return String.format("/sys/class/switch/%s/state", mDevName);
+            }
+
+            public boolean checkSwitchExists() {
+                File f = new File(getSwitchStatePath());
+                return f.exists();
+            }
+
+            public int computeNewHeadsetState(int headsetState, int switchState) {
+                int preserveMask = ~(mState1Bits | mState2Bits);
+                int setBits = ((switchState == 1) ? mState1Bits :
+                              ((switchState == 2) ? mState2Bits : 0));
+
+                return ((headsetState & preserveMask) | setBits);
+            }
+        }
+    }
+}