/* * Copyright (C) 2013 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.wifi; import android.app.AlarmManager; import android.app.PendingIntent; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.database.ContentObserver; import android.net.ConnectivityManager; import android.net.NetworkInfo; import android.net.wifi.WifiConfiguration; import android.net.wifi.WifiManager; import static android.net.wifi.WifiManager.WIFI_MODE_FULL; import static android.net.wifi.WifiManager.WIFI_MODE_FULL_HIGH_PERF; import static android.net.wifi.WifiManager.WIFI_MODE_SCAN_ONLY; import android.net.wifi.WifiStateMachine; import android.os.Handler; import android.os.Looper; import android.os.Message; import android.os.SystemClock; import android.os.WorkSource; import android.provider.Settings; import android.util.Slog; import com.android.internal.util.Protocol; import com.android.internal.util.State; import com.android.internal.util.StateMachine; import com.android.server.wifi.WifiService.LockList; import java.io.FileDescriptor; import java.io.PrintWriter; class WifiController extends StateMachine { private static final String TAG = "WifiController"; private static final boolean DBG = false; private Context mContext; private boolean mScreenOff; private boolean mDeviceIdle; private int mPluggedType; private int mStayAwakeConditions; private long mIdleMillis; private int mSleepPolicy; private AlarmManager mAlarmManager; private PendingIntent mIdleIntent; private static final int IDLE_REQUEST = 0; /** * See {@link Settings.Global#WIFI_IDLE_MS}. This is the default value if a * Settings.Global value is not present. This timeout value is chosen as * the approximate point at which the battery drain caused by Wi-Fi * being enabled but not active exceeds the battery drain caused by * re-establishing a connection to the mobile data network. */ private static final long DEFAULT_IDLE_MS = 15 * 60 * 1000; /* 15 minutes */ /** * See {@link Settings.Global#WIFI_REENABLE_DELAY_MS}. This is the default value if a * Settings.Global value is not present. This is the minimum time after wifi is disabled * we'll act on an enable. Enable requests received before this delay will be deferred. */ private static final long DEFAULT_REENABLE_DELAY_MS = 500; // finding that delayed messages can sometimes be delivered earlier than expected // probably rounding errors.. add a margin to prevent problems private static final long DEFER_MARGIN_MS = 5; NetworkInfo mNetworkInfo = new NetworkInfo(ConnectivityManager.TYPE_WIFI, 0, "WIFI", ""); private static final String ACTION_DEVICE_IDLE = "com.android.server.WifiManager.action.DEVICE_IDLE"; /* References to values tracked in WifiService */ final WifiStateMachine mWifiStateMachine; final WifiSettingsStore mSettingsStore; final LockList mLocks; /** * Temporary for computing UIDS that are responsible for starting WIFI. * Protected by mWifiStateTracker lock. */ private final WorkSource mTmpWorkSource = new WorkSource(); private long mReEnableDelayMillis; private static final int BASE = Protocol.BASE_WIFI_CONTROLLER; static final int CMD_EMERGENCY_MODE_CHANGED = BASE + 1; static final int CMD_SCREEN_ON = BASE + 2; static final int CMD_SCREEN_OFF = BASE + 3; static final int CMD_BATTERY_CHANGED = BASE + 4; static final int CMD_DEVICE_IDLE = BASE + 5; static final int CMD_LOCKS_CHANGED = BASE + 6; static final int CMD_SCAN_ALWAYS_MODE_CHANGED = BASE + 7; static final int CMD_WIFI_TOGGLED = BASE + 8; static final int CMD_AIRPLANE_TOGGLED = BASE + 9; static final int CMD_SET_AP = BASE + 10; static final int CMD_DEFERRED_TOGGLE = BASE + 11; private DefaultState mDefaultState = new DefaultState(); private StaEnabledState mStaEnabledState = new StaEnabledState(); private ApStaDisabledState mApStaDisabledState = new ApStaDisabledState(); private StaDisabledWithScanState mStaDisabledWithScanState = new StaDisabledWithScanState(); private ApEnabledState mApEnabledState = new ApEnabledState(); private DeviceActiveState mDeviceActiveState = new DeviceActiveState(); private DeviceInactiveState mDeviceInactiveState = new DeviceInactiveState(); private ScanOnlyLockHeldState mScanOnlyLockHeldState = new ScanOnlyLockHeldState(); private FullLockHeldState mFullLockHeldState = new FullLockHeldState(); private FullHighPerfLockHeldState mFullHighPerfLockHeldState = new FullHighPerfLockHeldState(); private NoLockHeldState mNoLockHeldState = new NoLockHeldState(); private EcmState mEcmState = new EcmState(); WifiController(Context context, WifiService service, Looper looper) { super(TAG, looper); mContext = context; mWifiStateMachine = service.mWifiStateMachine; mSettingsStore = service.mSettingsStore; mLocks = service.mLocks; mAlarmManager = (AlarmManager)mContext.getSystemService(Context.ALARM_SERVICE); Intent idleIntent = new Intent(ACTION_DEVICE_IDLE, null); mIdleIntent = PendingIntent.getBroadcast(mContext, IDLE_REQUEST, idleIntent, 0); addState(mDefaultState); addState(mApStaDisabledState, mDefaultState); addState(mStaEnabledState, mDefaultState); addState(mDeviceActiveState, mStaEnabledState); addState(mDeviceInactiveState, mStaEnabledState); addState(mScanOnlyLockHeldState, mDeviceInactiveState); addState(mFullLockHeldState, mDeviceInactiveState); addState(mFullHighPerfLockHeldState, mDeviceInactiveState); addState(mNoLockHeldState, mDeviceInactiveState); addState(mStaDisabledWithScanState, mDefaultState); addState(mApEnabledState, mDefaultState); addState(mEcmState, mDefaultState); if (mSettingsStore.isScanAlwaysAvailable()) { setInitialState(mStaDisabledWithScanState); } else { setInitialState(mApStaDisabledState); } setLogRecSize(100); setLogOnlyTransitions(false); IntentFilter filter = new IntentFilter(); filter.addAction(ACTION_DEVICE_IDLE); filter.addAction(WifiManager.NETWORK_STATE_CHANGED_ACTION); mContext.registerReceiver( new BroadcastReceiver() { @Override public void onReceive(Context context, Intent intent) { String action = intent.getAction(); if (action.equals(ACTION_DEVICE_IDLE)) { sendMessage(CMD_DEVICE_IDLE); } else if (action.equals(WifiManager.NETWORK_STATE_CHANGED_ACTION)) { mNetworkInfo = (NetworkInfo) intent.getParcelableExtra( WifiManager.EXTRA_NETWORK_INFO); } } }, new IntentFilter(filter)); initializeAndRegisterForSettingsChange(looper); } private void initializeAndRegisterForSettingsChange(Looper looper) { Handler handler = new Handler(looper); readStayAwakeConditions(); registerForStayAwakeModeChange(handler); readWifiIdleTime(); registerForWifiIdleTimeChange(handler); readWifiSleepPolicy(); registerForWifiSleepPolicyChange(handler); readWifiReEnableDelay(); } private void readStayAwakeConditions() { mStayAwakeConditions = Settings.Global.getInt(mContext.getContentResolver(), Settings.Global.STAY_ON_WHILE_PLUGGED_IN, 0); } private void readWifiIdleTime() { mIdleMillis = Settings.Global.getLong(mContext.getContentResolver(), Settings.Global.WIFI_IDLE_MS, DEFAULT_IDLE_MS); } private void readWifiSleepPolicy() { mSleepPolicy = Settings.Global.getInt(mContext.getContentResolver(), Settings.Global.WIFI_SLEEP_POLICY, Settings.Global.WIFI_SLEEP_POLICY_NEVER); } private void readWifiReEnableDelay() { mReEnableDelayMillis = Settings.Global.getLong(mContext.getContentResolver(), Settings.Global.WIFI_REENABLE_DELAY_MS, DEFAULT_REENABLE_DELAY_MS); } /** * Observes settings changes to scan always mode. */ private void registerForStayAwakeModeChange(Handler handler) { ContentObserver contentObserver = new ContentObserver(handler) { @Override public void onChange(boolean selfChange) { readStayAwakeConditions(); } }; mContext.getContentResolver().registerContentObserver( Settings.Global.getUriFor(Settings.Global.STAY_ON_WHILE_PLUGGED_IN), false, contentObserver); } /** * Observes settings changes to scan always mode. */ private void registerForWifiIdleTimeChange(Handler handler) { ContentObserver contentObserver = new ContentObserver(handler) { @Override public void onChange(boolean selfChange) { readWifiIdleTime(); } }; mContext.getContentResolver().registerContentObserver( Settings.Global.getUriFor(Settings.Global.WIFI_IDLE_MS), false, contentObserver); } /** * Observes changes to wifi sleep policy */ private void registerForWifiSleepPolicyChange(Handler handler) { ContentObserver contentObserver = new ContentObserver(handler) { @Override public void onChange(boolean selfChange) { readWifiSleepPolicy(); } }; mContext.getContentResolver().registerContentObserver( Settings.Global.getUriFor(Settings.Global.WIFI_SLEEP_POLICY), false, contentObserver); } /** * Determines whether the Wi-Fi chipset should stay awake or be put to * sleep. Looks at the setting for the sleep policy and the current * conditions. * * @see #shouldDeviceStayAwake(int) */ private boolean shouldWifiStayAwake(int pluggedType) { if (mSleepPolicy == Settings.Global.WIFI_SLEEP_POLICY_NEVER) { // Never sleep return true; } else if ((mSleepPolicy == Settings.Global.WIFI_SLEEP_POLICY_NEVER_WHILE_PLUGGED) && (pluggedType != 0)) { // Never sleep while plugged, and we're plugged return true; } else { // Default return shouldDeviceStayAwake(pluggedType); } } /** * Determine whether the bit value corresponding to {@code pluggedType} is set in * the bit string mStayAwakeConditions. This determines whether the device should * stay awake based on the current plugged type. * * @param pluggedType the type of plug (USB, AC, or none) for which the check is * being made * @return {@code true} if {@code pluggedType} indicates that the device is * supposed to stay awake, {@code false} otherwise. */ private boolean shouldDeviceStayAwake(int pluggedType) { return (mStayAwakeConditions & pluggedType) != 0; } private void updateBatteryWorkSource() { mTmpWorkSource.clear(); if (mDeviceIdle) { mLocks.updateWorkSource(mTmpWorkSource); } mWifiStateMachine.updateBatteryWorkSource(mTmpWorkSource); } class DefaultState extends State { @Override public boolean processMessage(Message msg) { switch (msg.what) { case CMD_SCREEN_ON: mAlarmManager.cancel(mIdleIntent); mScreenOff = false; mDeviceIdle = false; updateBatteryWorkSource(); break; case CMD_SCREEN_OFF: mScreenOff = true; /* * Set a timer to put Wi-Fi to sleep, but only if the screen is off * AND the "stay on while plugged in" setting doesn't match the * current power conditions (i.e, not plugged in, plugged in to USB, * or plugged in to AC). */ if (!shouldWifiStayAwake(mPluggedType)) { //Delayed shutdown if wifi is connected if (mNetworkInfo.getDetailedState() == NetworkInfo.DetailedState.CONNECTED) { if (DBG) Slog.d(TAG, "set idle timer: " + mIdleMillis + " ms"); mAlarmManager.set(AlarmManager.RTC_WAKEUP, System.currentTimeMillis() + mIdleMillis, mIdleIntent); } else { sendMessage(CMD_DEVICE_IDLE); } } break; case CMD_DEVICE_IDLE: mDeviceIdle = true; updateBatteryWorkSource(); break; case CMD_BATTERY_CHANGED: /* * Set a timer to put Wi-Fi to sleep, but only if the screen is off * AND we are transitioning from a state in which the device was supposed * to stay awake to a state in which it is not supposed to stay awake. * If "stay awake" state is not changing, we do nothing, to avoid resetting * the already-set timer. */ int pluggedType = msg.arg1; if (DBG) Slog.d(TAG, "battery changed pluggedType: " + pluggedType); if (mScreenOff && shouldWifiStayAwake(mPluggedType) && !shouldWifiStayAwake(pluggedType)) { long triggerTime = System.currentTimeMillis() + mIdleMillis; if (DBG) Slog.d(TAG, "set idle timer for " + mIdleMillis + "ms"); mAlarmManager.set(AlarmManager.RTC_WAKEUP, triggerTime, mIdleIntent); } mPluggedType = pluggedType; break; case CMD_SET_AP: case CMD_SCAN_ALWAYS_MODE_CHANGED: case CMD_LOCKS_CHANGED: case CMD_WIFI_TOGGLED: case CMD_AIRPLANE_TOGGLED: case CMD_EMERGENCY_MODE_CHANGED: break; case CMD_DEFERRED_TOGGLE: log("DEFERRED_TOGGLE ignored due to state change"); break; default: throw new RuntimeException("WifiController.handleMessage " + msg.what); } return HANDLED; } } class ApStaDisabledState extends State { private int mDeferredEnableSerialNumber = 0; private boolean mHaveDeferredEnable = false; private long mDisabledTimestamp; @Override public void enter() { mWifiStateMachine.setSupplicantRunning(false); // Supplicant can't restart right away, so not the time we switched off mDisabledTimestamp = SystemClock.elapsedRealtime(); mDeferredEnableSerialNumber++; mHaveDeferredEnable = false; } @Override public boolean processMessage(Message msg) { switch (msg.what) { case CMD_WIFI_TOGGLED: case CMD_AIRPLANE_TOGGLED: if (mSettingsStore.isWifiToggleEnabled()) { if (doDeferEnable(msg)) { if (mHaveDeferredEnable) { // have 2 toggles now, inc serial number an ignore both mDeferredEnableSerialNumber++; } mHaveDeferredEnable = !mHaveDeferredEnable; break; } if (mDeviceIdle == false) { transitionTo(mDeviceActiveState); } else { checkLocksAndTransitionWhenDeviceIdle(); } } break; case CMD_SCAN_ALWAYS_MODE_CHANGED: if (mSettingsStore.isScanAlwaysAvailable()) { transitionTo(mStaDisabledWithScanState); } break; case CMD_SET_AP: if (msg.arg1 == 1) { mWifiStateMachine.setHostApRunning((WifiConfiguration) msg.obj, true); transitionTo(mApEnabledState); } break; case CMD_DEFERRED_TOGGLE: if (msg.arg1 != mDeferredEnableSerialNumber) { log("DEFERRED_TOGGLE ignored due to serial mismatch"); break; } log("DEFERRED_TOGGLE handled"); sendMessage((Message)(msg.obj)); break; default: return NOT_HANDLED; } return HANDLED; } private boolean doDeferEnable(Message msg) { long delaySoFar = SystemClock.elapsedRealtime() - mDisabledTimestamp; if (delaySoFar >= mReEnableDelayMillis) { return false; } log("WifiController msg " + msg + " deferred for " + (mReEnableDelayMillis - delaySoFar) + "ms"); // need to defer this action. Message deferredMsg = obtainMessage(CMD_DEFERRED_TOGGLE); deferredMsg.obj = Message.obtain(msg); deferredMsg.arg1 = ++mDeferredEnableSerialNumber; sendMessageDelayed(deferredMsg, mReEnableDelayMillis - delaySoFar + DEFER_MARGIN_MS); return true; } } class StaEnabledState extends State { @Override public void enter() { mWifiStateMachine.setSupplicantRunning(true); } @Override public boolean processMessage(Message msg) { switch (msg.what) { case CMD_WIFI_TOGGLED: if (! mSettingsStore.isWifiToggleEnabled()) { if (mSettingsStore.isScanAlwaysAvailable()) { transitionTo(mStaDisabledWithScanState); } else { transitionTo(mApStaDisabledState); } } break; case CMD_AIRPLANE_TOGGLED: /* When wi-fi is turned off due to airplane, * disable entirely (including scan) */ if (! mSettingsStore.isWifiToggleEnabled()) { transitionTo(mApStaDisabledState); } break; case CMD_EMERGENCY_MODE_CHANGED: if (msg.arg1 == 1) { transitionTo(mEcmState); break; } default: return NOT_HANDLED; } return HANDLED; } } class StaDisabledWithScanState extends State { private int mDeferredEnableSerialNumber = 0; private boolean mHaveDeferredEnable = false; private long mDisabledTimestamp; @Override public void enter() { mWifiStateMachine.setSupplicantRunning(true); mWifiStateMachine.setOperationalMode(WifiStateMachine.SCAN_ONLY_WITH_WIFI_OFF_MODE); mWifiStateMachine.setDriverStart(true); // Supplicant can't restart right away, so not the time we switched off mDisabledTimestamp = SystemClock.elapsedRealtime(); mDeferredEnableSerialNumber++; mHaveDeferredEnable = false; } @Override public boolean processMessage(Message msg) { switch (msg.what) { case CMD_WIFI_TOGGLED: if (mSettingsStore.isWifiToggleEnabled()) { if (doDeferEnable(msg)) { if (mHaveDeferredEnable) { // have 2 toggles now, inc serial number and ignore both mDeferredEnableSerialNumber++; } mHaveDeferredEnable = !mHaveDeferredEnable; break; } if (mDeviceIdle == false) { transitionTo(mDeviceActiveState); } else { checkLocksAndTransitionWhenDeviceIdle(); } } break; case CMD_AIRPLANE_TOGGLED: if (mSettingsStore.isAirplaneModeOn() && ! mSettingsStore.isWifiToggleEnabled()) { transitionTo(mApStaDisabledState); } case CMD_SCAN_ALWAYS_MODE_CHANGED: if (! mSettingsStore.isScanAlwaysAvailable()) { transitionTo(mApStaDisabledState); } break; case CMD_SET_AP: // Before starting tethering, turn off supplicant for scan mode if (msg.arg1 == 1) { deferMessage(msg); transitionTo(mApStaDisabledState); } break; case CMD_DEFERRED_TOGGLE: if (msg.arg1 != mDeferredEnableSerialNumber) { log("DEFERRED_TOGGLE ignored due to serial mismatch"); break; } logd("DEFERRED_TOGGLE handled"); sendMessage((Message)(msg.obj)); break; default: return NOT_HANDLED; } return HANDLED; } private boolean doDeferEnable(Message msg) { long delaySoFar = SystemClock.elapsedRealtime() - mDisabledTimestamp; if (delaySoFar >= mReEnableDelayMillis) { return false; } log("WifiController msg " + msg + " deferred for " + (mReEnableDelayMillis - delaySoFar) + "ms"); // need to defer this action. Message deferredMsg = obtainMessage(CMD_DEFERRED_TOGGLE); deferredMsg.obj = Message.obtain(msg); deferredMsg.arg1 = ++mDeferredEnableSerialNumber; sendMessageDelayed(deferredMsg, mReEnableDelayMillis - delaySoFar + DEFER_MARGIN_MS); return true; } } class ApEnabledState extends State { @Override public boolean processMessage(Message msg) { switch (msg.what) { case CMD_AIRPLANE_TOGGLED: if (mSettingsStore.isAirplaneModeOn()) { mWifiStateMachine.setHostApRunning(null, false); transitionTo(mApStaDisabledState); } break; case CMD_SET_AP: if (msg.arg1 == 0) { mWifiStateMachine.setHostApRunning(null, false); transitionTo(mApStaDisabledState); } break; default: return NOT_HANDLED; } return HANDLED; } } class EcmState extends State { @Override public void enter() { mWifiStateMachine.setSupplicantRunning(false); } @Override public boolean processMessage(Message msg) { if (msg.what == CMD_EMERGENCY_MODE_CHANGED && msg.arg1 == 0) { if (mSettingsStore.isWifiToggleEnabled()) { if (mDeviceIdle == false) { transitionTo(mDeviceActiveState); } else { checkLocksAndTransitionWhenDeviceIdle(); } } else if (mSettingsStore.isScanAlwaysAvailable()) { transitionTo(mStaDisabledWithScanState); } else { transitionTo(mApStaDisabledState); } return HANDLED; } else { return NOT_HANDLED; } } } /* Parent: StaEnabledState */ class DeviceActiveState extends State { @Override public void enter() { mWifiStateMachine.setOperationalMode(WifiStateMachine.CONNECT_MODE); mWifiStateMachine.setDriverStart(true); mWifiStateMachine.setHighPerfModeEnabled(false); } @Override public boolean processMessage(Message msg) { if (msg.what == CMD_DEVICE_IDLE) { checkLocksAndTransitionWhenDeviceIdle(); // We let default state handle the rest of work } return NOT_HANDLED; } } /* Parent: StaEnabledState */ class DeviceInactiveState extends State { @Override public boolean processMessage(Message msg) { switch (msg.what) { case CMD_LOCKS_CHANGED: checkLocksAndTransitionWhenDeviceIdle(); updateBatteryWorkSource(); return HANDLED; case CMD_SCREEN_ON: transitionTo(mDeviceActiveState); // More work in default state return NOT_HANDLED; default: return NOT_HANDLED; } } } /* Parent: DeviceInactiveState. Device is inactive, but an app is holding a scan only lock. */ class ScanOnlyLockHeldState extends State { @Override public void enter() { mWifiStateMachine.setOperationalMode(WifiStateMachine.SCAN_ONLY_MODE); mWifiStateMachine.setDriverStart(true); } } /* Parent: DeviceInactiveState. Device is inactive, but an app is holding a full lock. */ class FullLockHeldState extends State { @Override public void enter() { mWifiStateMachine.setOperationalMode(WifiStateMachine.CONNECT_MODE); mWifiStateMachine.setDriverStart(true); mWifiStateMachine.setHighPerfModeEnabled(false); } } /* Parent: DeviceInactiveState. Device is inactive, but an app is holding a high perf lock. */ class FullHighPerfLockHeldState extends State { @Override public void enter() { mWifiStateMachine.setOperationalMode(WifiStateMachine.CONNECT_MODE); mWifiStateMachine.setDriverStart(true); mWifiStateMachine.setHighPerfModeEnabled(true); } } /* Parent: DeviceInactiveState. Device is inactive and no app is holding a wifi lock. */ class NoLockHeldState extends State { @Override public void enter() { mWifiStateMachine.setDriverStart(false); } } private void checkLocksAndTransitionWhenDeviceIdle() { if (mLocks.hasLocks()) { switch (mLocks.getStrongestLockMode()) { case WIFI_MODE_FULL: transitionTo(mFullLockHeldState); break; case WIFI_MODE_FULL_HIGH_PERF: transitionTo(mFullHighPerfLockHeldState); break; case WIFI_MODE_SCAN_ONLY: transitionTo(mScanOnlyLockHeldState); break; default: loge("Illegal lock " + mLocks.getStrongestLockMode()); } } else { if (mSettingsStore.isScanAlwaysAvailable()) { transitionTo(mScanOnlyLockHeldState); } else { transitionTo(mNoLockHeldState); } } } @Override public void dump(FileDescriptor fd, PrintWriter pw, String[] args) { super.dump(fd, pw, args); pw.println("mScreenOff " + mScreenOff); pw.println("mDeviceIdle " + mDeviceIdle); pw.println("mPluggedType " + mPluggedType); pw.println("mIdleMillis " + mIdleMillis); pw.println("mSleepPolicy " + mSleepPolicy); } }