Power manager rewrite.

The major goal of this rewrite is to make it easier to implement
power management policies correctly.  According, the new
implementation primarily uses state-based rather than event-based
triggers for applying changes to the current power state.

For example, when an application requests that the proximity
sensor be used to manage the screen state (by way of a wake lock),
the power manager makes note of the fact that the set of
wake locks changed.  Then it executes a common update function
that recalculates the entire state, first looking at wake locks,
then considering user activity, and eventually determining whether
the screen should be turned on or off.  At this point it may
make a request to a component called the DisplayPowerController
to asynchronously update the display's powe state.  Likewise,
DisplayPowerController makes note of the updated power request
and schedules its own update function to figure out what needs
to be changed.

The big benefit of this approach is that it's easy to mutate
multiple properties of the power state simultaneously then
apply their joint effects together all at once.  Transitions
between states are detected and resolved by the update in
a consistent manner.

The new power manager service has is implemented as a set of
loosely coupled components.  For the most part, information
only flows one way through these components (by issuing a
request to that component) although some components support
sending a message back to indicate when the work has been
completed.  For example, the DisplayPowerController posts
a callback runnable asynchronously to tell the PowerManagerService
when the display is ready.  An important feature of this
approach is that each component neatly encapsulates its
state and maintains its own invariants.  Moreover, we do
not need to worry about deadlocks or awkward mutual exclusion
semantics because most of the requests are asynchronous.

The benefits of this design are especially apparent in
the implementation of the screen on / off and brightness
control animations which are able to take advantage of
framework features like properties, ObjectAnimator
and Choreographer.

The screen on / off animation is now the responsibility
of the power manager (instead of surface flinger).  This change
makes it much easier to ensure that the animation is properly
coordinated with other power state changes and eliminates
the cause of race conditions in the older implementation.

The because of the userActivity() function has been changed
so that it never wakes the device from sleep.  This change
removes ambiguity around forcing or disabling user activity
for various purposes.  To wake the device, use wakeUp().
To put it to sleep, use goToSleep().  Simple.

The power manager service interface and API has been significantly
simplified and consolidated.  Also fixed some inconsistencies
related to how the minimum and maximum screen brightness setting
was presented in brightness control widgets and enforced behind
the scenes.

At present the following features are implemented:

- Wake locks.
- User activity.
- Wake up / go to sleep.
- Power state broadcasts.
- Battery stats and event log notifications.
- Dreams.
- Proximity screen off.
- Animated screen on / off transitions.
- Auto-dimming.
- Auto-brightness control for the screen backlight with
  different timeouts for ramping up versus ramping down.
- Auto-on when plugged or unplugged.
- Stay on when plugged.
- Device administration maximum user activity timeout.
- Application controlled brightness via window manager.

The following features are not yet implemented:

- Reduced user activity timeout for the key guard.
- Reduced user activity timeout for the phone application.
- Coordinating screen on barriers with the window manager.
- Preventing auto-rotation during power state changes.
- Auto-brightness adjustment setting (feature was disabled
  in previous version of the power manager service pending
  an improved UI design so leaving it out for now).
- Interpolated brightness control (a proposed new scheme
  for more compactly specifying auto-brightness levels
  in config.xml).
- Button / keyboard backlight control.
- Change window manager to associated WorkSource with
  KEEP_SCREEN_ON_FLAG wake lock instead of talking
  directly to the battery stats service.
- Optionally support animating screen brightness when
  turning on/off instead of playing electron beam animation
  (config_animateScreenLights).

Change-Id: I1d7a52e98f0449f76d70bf421f6a7f245957d1d7

Author: Jeff Brown

api/current.txt

@@ -16269,6 +16269,7 @@ package android.os {
     method public android.os.PowerManager.WakeLock newWakeLock(int, java.lang.String);
     method public void reboot(java.lang.String);
     method public void userActivity(long, boolean);
+    method public void wakeUp(long);
     field public static final int ACQUIRE_CAUSES_WAKEUP = 268435456; // 0x10000000
     field public static final deprecated int FULL_WAKE_LOCK = 26; // 0x1a
     field public static final int ON_AFTER_RELEASE = 536870912; // 0x20000000
@@ -18759,7 +18760,7 @@ package android.provider {
     field public static final android.net.Uri DEFAULT_NOTIFICATION_URI;
     field public static final android.net.Uri DEFAULT_RINGTONE_URI;
     field public static final deprecated java.lang.String DEVICE_PROVISIONED = "device_provisioned";
-    field public static final java.lang.String DIM_SCREEN = "dim_screen";
+    field public static final deprecated java.lang.String DIM_SCREEN = "dim_screen";
     field public static final java.lang.String DTMF_TONE_WHEN_DIALING = "dtmf_tone";
     field public static final java.lang.String END_BUTTON_BEHAVIOR = "end_button_behavior";
     field public static final java.lang.String FONT_SCALE = "font_scale";

cmds/svc/src/com/android/commands/svc/PowerCommand.java

@@ -64,7 +64,7 @@ else if ("false".equals(args[2])) {
                             = IPowerManager.Stub.asInterface(ServiceManager.getService(Context.POWER_SERVICE));
                     try {
                         IBinder lock = new Binder();
-                        pm.acquireWakeLock(PowerManager.FULL_WAKE_LOCK, lock, "svc power", null);
+                        pm.acquireWakeLock(lock, PowerManager.FULL_WAKE_LOCK, "svc power", null);
                         pm.setStayOnSetting(val);
                         pm.releaseWakeLock(lock, 0);
                     }

core/java/android/app/ContextImpl.java

@@ -418,7 +418,8 @@ public Object createService(ContextImpl ctx) {
                 public Object createService(ContextImpl ctx) {
                     IBinder b = ServiceManager.getService(POWER_SERVICE);
                     IPowerManager service = IPowerManager.Stub.asInterface(b);
-                    return new PowerManager(service, ctx.mMainThread.getHandler());
+                    return new PowerManager(ctx.getOuterContext(),
+                            service, ctx.mMainThread.getHandler());
                 }});
 
         registerService(SEARCH_SERVICE, new ServiceFetcher() {

core/java/android/os/IPowerManager.aidl

@@ -23,27 +23,33 @@ import android.os.WorkSource;
 
 interface IPowerManager
 {
-    // WARNING: changes in acquireWakeLock() signature must be reflected in IPowerManager.cpp/h
-    void acquireWakeLock(int flags, IBinder lock, String tag, in WorkSource ws);
-    void updateWakeLockWorkSource(IBinder lock, in WorkSource ws);
-    void goToSleep(long time);
-    void goToSleepWithReason(long time, int reason);
-    // WARNING: changes in releaseWakeLock() signature must be reflected in IPowerManager.cpp/h
+    // WARNING: The first two methods must remain the first two methods because their
+    // transaction numbers must not change unless IPowerManager.cpp is also updated.
+    void acquireWakeLock(IBinder lock, int flags, String tag, in WorkSource ws);
     void releaseWakeLock(IBinder lock, int flags);
-    void userActivity(long when, boolean noChangeLights);
-    void userActivityWithForce(long when, boolean noChangeLights, boolean force);
+
+    void updateWakeLockWorkSource(IBinder lock, in WorkSource ws);
+    boolean isWakeLockLevelSupported(int level);
+
+    void userActivity(long time, int event, int flags);
+    void wakeUp(long time);
+    void goToSleep(long time, int reason);
+
+    boolean isScreenOn();
+    void reboot(String reason);
+    void crash(String message);
+
     void clearUserActivityTimeout(long now, long timeout);
     void setPokeLock(int pokey, IBinder lock, String tag);
-    int getSupportedWakeLockFlags();
     void setStayOnSetting(int val);
-    void setMaximumScreenOffTimeount(int timeMs);
+    void setMaximumScreenOffTimeoutFromDeviceAdmin(int timeMs);
     void preventScreenOn(boolean prevent);
-    boolean isScreenOn();
-    void reboot(String reason);
-    void crash(String message);
 
-    // sets the brightness of the backlights (screen, keyboard, button) 0-255
-    void setBacklightBrightness(int brightness);
+    // temporarily overrides the screen brightness settings to allow the user to
+    // see the effect of a settings change without applying it immediately
+    void setTemporaryScreenBrightnessSettingOverride(int brightness);
+    void setTemporaryScreenAutoBrightnessAdjustmentSettingOverride(float adj);
+
+    // sets the attention light (used by phone app only)
     void setAttentionLight(boolean on, int color);
-    void setAutoBrightnessAdjustment(float adj);
 }

core/java/android/os/LocalPowerManager.java

@@ -18,25 +18,11 @@
 
 /** @hide */
 public interface LocalPowerManager {
+    // FIXME: Replace poke locks with something else.
+
     public static final int POKE_LOCK_IGNORE_TOUCH_EVENTS = 0x1;
 
     public static final int POKE_LOCK_SHORT_TIMEOUT = 0x2;
     public static final int POKE_LOCK_MEDIUM_TIMEOUT = 0x4;
     public static final int POKE_LOCK_TIMEOUT_MASK = 0x6;
-
-    void goToSleep(long time);
-    
-    // notify power manager when keyboard is opened/closed
-    void setKeyboardVisibility(boolean visible);
-
-    // when the keyguard is up, it manages the power state, and userActivity doesn't do anything.
-    void enableUserActivity(boolean enabled);
-
-    // the same as the method on PowerManager
-    void userActivity(long time, boolean noChangeLights, int eventType);
-
-    boolean isScreenOn();
-
-    void setScreenBrightnessOverride(int brightness);
-    void setButtonBrightnessOverride(int brightness);
 }

core/java/android/os/PowerManager.java

@@ -16,6 +16,7 @@
 
 package android.os;
 
+import android.content.Context;
 import android.util.Log;
 
 /**
@@ -42,8 +43,8 @@
  * wl.release();
  * }
  * </p><p>
- * The following flags are defined, with varying effects on system power.
- * <i>These flags are mutually exclusive - you may only specify one of them.</i>
+ * The following wake lock levels are defined, with varying effects on system power.
+ * <i>These levels are mutually exclusive - you may only specify one of them.</i>
  *
  * <table border="2" width="85%" align="center" frame="hsides" rules="rows">
  *     <thead>
@@ -177,7 +178,7 @@ public final class PowerManager {
     /**
      * Wake lock level: Turns the screen off when the proximity sensor activates.
      * <p>
-     * Since not all devices have proximity sensors, use {@link #getSupportedWakeLockFlags}
+     * Since not all devices have proximity sensors, use {@link #isWakeLockLevelSupported}
      * to determine whether this wake lock level is supported.
      * </p>
      *
@@ -226,29 +227,24 @@ public final class PowerManager {
      */
     public static final int WAIT_FOR_PROXIMITY_NEGATIVE = 1;
 
-    /**
-     * Brightness value to use when battery is low.
-     * @hide
-     */
-    public static final int BRIGHTNESS_LOW_BATTERY = 10;
-
     /**
      * Brightness value for fully on.
      * @hide
      */
     public static final int BRIGHTNESS_ON = 255;
 
     /**
-     * Brightness value for dim backlight.
+     * Brightness value for fully off.
      * @hide
      */
-    public static final int BRIGHTNESS_DIM = 20;
+    public static final int BRIGHTNESS_OFF = 0;
 
     /**
-     * Brightness value for fully off.
+     * A nominal default brightness value.
+     * Use {@link #getDefaultScreenBrightnessSetting()} instead.
      * @hide
      */
-    public static final int BRIGHTNESS_OFF = 0;
+    private static final int BRIGHTNESS_DEFAULT = 102;
 
     // Note: Be sure to update android.os.BatteryStats and PowerManager.h
     // if adding or modifying user activity event constants.
@@ -271,17 +267,81 @@ public final class PowerManager {
      */
     public static final int USER_ACTIVITY_EVENT_TOUCH = 2;
 
+    /**
+     * User activity flag: Do not restart the user activity timeout or brighten
+     * the display in response to user activity if it is already dimmed.
+     * @hide
+     */
+    public static final int USER_ACTIVITY_FLAG_NO_CHANGE_LIGHTS = 1 << 0;
+
+    /**
+     * Special wake lock tag used for the wake lock in the Window Manager that handles the
+     * {@link android.view.WindowManager.LayoutParams#FLAG_KEEP_SCREEN_ON} flag.
+     * @hide
+     */
+    public static final String KEEP_SCREEN_ON_FLAG_TAG = "KEEP_SCREEN_ON_FLAG";
+
+    /**
+     * Go to sleep reason code: Going to sleep due by user request.
+     * @hide
+     */
+    public static final int GO_TO_SLEEP_REASON_USER = 0;
+
+    /**
+     * Go to sleep reason code: Going to sleep due by request of the
+     * device administration policy.
+     * @hide
+     */
+    public static final int GO_TO_SLEEP_REASON_DEVICE_ADMIN = 1;
+
+    /**
+     * Go to sleep reason code: Going to sleep due to a screen timeout.
+     * @hide
+     */
+    public static final int GO_TO_SLEEP_REASON_TIMEOUT = 2;
+
+    final Context mContext;
     final IPowerManager mService;
     final Handler mHandler;
 
     /**
      * {@hide}
      */
-    public PowerManager(IPowerManager service, Handler handler) {
+    public PowerManager(Context context, IPowerManager service, Handler handler) {
+        mContext = context;
         mService = service;
         mHandler = handler;
     }
 
+    /**
+     * Gets the minimum supported screen brightness setting.
+     * The screen may be allowed to become dimmer than this value but
+     * this is the minimum value that can be set by the user.
+     * @hide
+     */
+    public int getMinimumScreenBrightnessSetting() {
+        return mContext.getResources().getInteger(
+                com.android.internal.R.integer.config_screenBrightnessDim);
+    }
+
+    /**
+     * Gets the maximum supported screen brightness setting.
+     * The screen may be allowed to become dimmer than this value but
+     * this is the maximum value that can be set by the user.
+     * @hide
+     */
+    public int getMaximumScreenBrightnessSetting() {
+        return BRIGHTNESS_ON;
+    }
+
+    /**
+     * Gets the default screen brightness setting.
+     * @hide
+     */
+    public int getDefaultScreenBrightnessSetting() {
+        return BRIGHTNESS_DEFAULT;
+    }
+
     /**
      * Creates a new wake lock with the specified level and flags.
      * <p>
@@ -360,8 +420,10 @@ public static void validateWakeLockParameters(int levelAndFlags, String tag) {
     /**
      * Notifies the power manager that user activity happened.
      * <p>
-     * Turns the device from whatever state it's in to full on, and resets
-     * the auto-off timer.
+     * Resets the auto-off timer and brightens the screen if the device
+     * is not asleep.  This is what happens normally when a key or the touch
+     * screen is pressed or when some other user activity occurs.
+     * This method does not wake up the device if it has been put to sleep.
      * </p><p>
      * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
      * </p>
@@ -375,19 +437,23 @@ public static void validateWakeLockParameters(int levelAndFlags, String tag) {
      * We want the device to stay on while the button is down, but we're about
      * to turn off the screen so we don't want the keyboard backlight to turn on again.
      * Otherwise the lights flash on and then off and it looks weird.
+     *
+     * @see #wakeUp
+     * @see #goToSleep
      */
     public void userActivity(long when, boolean noChangeLights) {
         try {
-            mService.userActivity(when, noChangeLights);
+            mService.userActivity(when, USER_ACTIVITY_EVENT_OTHER,
+                    noChangeLights ? USER_ACTIVITY_FLAG_NO_CHANGE_LIGHTS : 0);
         } catch (RemoteException e) {
         }
     }
 
    /**
      * Forces the device to go to sleep.
      * <p>
-     * Overrides all the wake locks that are held.  This is what happen when the power
-     * key is pressed to turn off the screen.
+     * Overrides all the wake locks that are held.
+     * This is what happens when the power key is pressed to turn off the screen.
      * </p><p>
      * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
      * </p>
@@ -396,10 +462,37 @@ public void userActivity(long when, boolean noChangeLights) {
      * {@link SystemClock#uptimeMillis()} time base.  This timestamp is used to correctly
      * order the user activity with other power management functions.  It should be set
      * to the timestamp of the input event that caused the request to go to sleep.
+     *
+     * @see #userActivity
+     * @see #wakeUp
      */
     public void goToSleep(long time) {
         try {
-            mService.goToSleep(time);
+            mService.goToSleep(time, GO_TO_SLEEP_REASON_USER);
+        } catch (RemoteException e) {
+        }
+    }
+
+    /**
+     * Forces the device to wake up from sleep.
+     * <p>
+     * If the device is currently asleep, wakes it up, otherwise does nothing.
+     * This is what happens when the power key is pressed to turn on the screen.
+     * </p><p>
+     * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
+     * </p>
+     *
+     * @param time The time when the request to wake up was issued, in the
+     * {@link SystemClock#uptimeMillis()} time base.  This timestamp is used to correctly
+     * order the user activity with other power management functions.  It should be set
+     * to the timestamp of the input event that caused the request to wake up.
+     *
+     * @see #userActivity
+     * @see #goToSleep
+     */
+    public void wakeUp(long time) {
+        try {
+            mService.wakeUp(time);
         } catch (RemoteException e) {
         }
     }
@@ -416,34 +509,24 @@ public void goToSleep(long time) {
      */
     public void setBacklightBrightness(int brightness) {
         try {
-            mService.setBacklightBrightness(brightness);
+            mService.setTemporaryScreenBrightnessSettingOverride(brightness);
         } catch (RemoteException e) {
         }
     }
 
    /**
-     * Returns the set of wake lock levels and flags for {@link #newWakeLock}
-     * that are supported on the device.
-     * <p>
-     * For example, to test to see if the {@link #PROXIMITY_SCREEN_OFF_WAKE_LOCK}
-     * is supported:
-     * {@samplecode
-     * PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
-     * int supportedFlags = pm.getSupportedWakeLockFlags();
-     * boolean proximitySupported = ((supportedFlags & PowerManager.PROXIMITY_SCREEN_OFF_WAKE_LOCK)
-     *         == PowerManager.PROXIMITY_SCREEN_OFF_WAKE_LOCK);
-     * }
-     * </p>
+     * Returns true if the specified wake lock level is supported.
      *
-     * @return The set of supported WakeLock flags.
+     * @param level The wake lock level to check.
+     * @return True if the specified wake lock level is supported.
      *
      * {@hide}
      */
-    public int getSupportedWakeLockFlags() {
+    public boolean isWakeLockLevelSupported(int level) {
         try {
-            return mService.getSupportedWakeLockFlags();
+            return mService.isWakeLockLevelSupported(level);
         } catch (RemoteException e) {
-            return 0;
+            return false;
         }
     }
 
@@ -593,7 +676,7 @@ private void acquireLocked() {
                 // been explicitly released by the keyguard.
                 mHandler.removeCallbacks(mReleaser);
                 try {
-                    mService.acquireWakeLock(mFlags, mToken, mTag, mWorkSource);
+                    mService.acquireWakeLock(mToken, mFlags, mTag, mWorkSource);
                 } catch (RemoteException e) {
                 }
                 mHeld = true;