Improvements to low power mode.

Add new public API for monitoring low power mode.

BatteryService now puts device in to low power mode when
battery level is low.

Window manager now watches low power mode to turn off
animations.

Modifying the animator scale now gets propagated to all
processes.

Change-Id: I8fa566994764ddd4e1977631e28381ab9409f8ee

1 files changed, 44 insertions, 3 deletions

diff --git a/services/core/java/com/android/server/power/PowerManagerService.java b/services/core/java/com/android/server/power/PowerManagerService.java
index aca17bf..d8671d9 100644
--- a/services/core/java/com/android/server/power/PowerManagerService.java
+++ b/services/core/java/com/android/server/power/PowerManagerService.java
@@ -406,6 +406,12 @@ public final class PowerManagerService extends com.android.server.SystemService
     // If true, the device is in low power mode.
     private boolean mLowPowerModeEnabled;
 
+    // Current state of the low power mode setting.
+    private boolean mLowPowerModeSetting;
+
+    // True if the battery level is currently considered low.
+    private boolean mBatteryLevelLow;
+
     private final ArrayList<PowerManagerInternal.LowPowerModeListener> mLowPowerModeListeners
             = new ArrayList<PowerManagerInternal.LowPowerModeListener>();
 
@@ -502,6 +508,7 @@ public final class PowerManagerService extends com.android.server.SystemService
             // Register for broadcasts from other components of the system.
             IntentFilter filter = new IntentFilter();
             filter.addAction(Intent.ACTION_BATTERY_CHANGED);
+            filter.setPriority(IntentFilter.SYSTEM_HIGH_PRIORITY);
             mContext.registerReceiver(new BatteryReceiver(), filter, null, mHandler);
 
             filter = new IntentFilter();
@@ -638,7 +645,18 @@ public final class PowerManagerService extends com.android.server.SystemService
 
         final boolean lowPowerModeEnabled = Settings.Global.getInt(resolver,
                 Settings.Global.LOW_POWER_MODE, 0) != 0;
-        if (lowPowerModeEnabled != mLowPowerModeEnabled) {
+        if (lowPowerModeEnabled != mLowPowerModeSetting) {
+            mLowPowerModeSetting = lowPowerModeEnabled;
+            updateLowPowerModeLocked();
+        }
+
+        mDirty |= DIRTY_SETTINGS;
+    }
+
+    void updateLowPowerModeLocked() {
+        final boolean lowPowerModeEnabled = mLowPowerModeSetting || mBatteryLevelLow;
+        if (mLowPowerModeEnabled != lowPowerModeEnabled) {
+            mLowPowerModeEnabled = lowPowerModeEnabled;
             powerHintInternal(POWER_HINT_LOW_POWER_MODE, lowPowerModeEnabled ? 1 : 0);
             mLowPowerModeEnabled = lowPowerModeEnabled;
             BackgroundThread.getHandler().post(new Runnable() {
@@ -652,11 +670,12 @@ public final class PowerManagerService extends com.android.server.SystemService
                     for (int i=0; i<listeners.size(); i++) {
                         listeners.get(i).onLowPowerModeChanged(lowPowerModeEnabled);
                     }
+                    Intent intent = new Intent(PowerManager.ACTION_POWER_SAVE_MODE_CHANGED);
+                    intent.addFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY);
+                    mContext.sendBroadcast(intent);
                 }
             });
         }
-
-        mDirty |= DIRTY_SETTINGS;
     }
 
     private void handleSettingsChangedLocked() {
@@ -1137,9 +1156,11 @@ public final class PowerManagerService extends com.android.server.SystemService
         if ((dirty & DIRTY_BATTERY_STATE) != 0) {
             final boolean wasPowered = mIsPowered;
             final int oldPlugType = mPlugType;
+            final boolean oldLevelLow = mBatteryLevelLow;
             mIsPowered = mBatteryService.isPowered(BatteryManager.BATTERY_PLUGGED_ANY);
             mPlugType = mBatteryService.getPlugType();
             mBatteryLevel = mBatteryService.getBatteryLevel();
+            mBatteryLevelLow = mBatteryService.getBatteryLevelLow();
 
             if (DEBUG_SPEW) {
                 Slog.d(TAG, "updateIsPoweredLocked: wasPowered=" + wasPowered
@@ -1175,6 +1196,10 @@ public final class PowerManagerService extends com.android.server.SystemService
                     mNotifier.onWirelessChargingStarted();
                 }
             }
+
+            if (oldLevelLow != mBatteryLevelLow) {
+                updateLowPowerModeLocked();
+            }
         }
     }
 
@@ -1896,6 +1921,12 @@ public final class PowerManagerService extends com.android.server.SystemService
         }
     }
 
+    private boolean isLowPowerModeInternal() {
+        synchronized (mLock) {
+            return mLowPowerModeEnabled;
+        }
+    }
+
     private void handleBatteryStateChangedLocked() {
         mDirty |= DIRTY_BATTERY_STATE;
         updatePowerStateLocked();
@@ -2764,6 +2795,16 @@ public final class PowerManagerService extends com.android.server.SystemService
             }
         }
 
+        @Override // Binder call
+        public boolean isPowerSaveMode() {
+            final long ident = Binder.clearCallingIdentity();
+            try {
+                return isLowPowerModeInternal();
+            } finally {
+                Binder.restoreCallingIdentity(ident);
+            }
+        }
+
         /**
          * Reboots the device.
          *