1 /*
2  * Copyright (C) 2007 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  */
16 
17 package android.os;
18 
19 import android.annotation.SdkConstant;
20 import android.annotation.SystemApi;
21 import android.content.Context;
22 import android.util.Log;
23 
24 /**
25  * This class gives you control of the power state of the device.
26  *
27  * <p>
28  * <b>Device battery life will be significantly affected by the use of this API.</b>
29  * Do not acquire {@link WakeLock}s unless you really need them, use the minimum levels
30  * possible, and be sure to release them as soon as possible.
31  * </p><p>
32  * You can obtain an instance of this class by calling
33  * {@link android.content.Context#getSystemService(java.lang.String) Context.getSystemService()}.
34  * </p><p>
35  * The primary API you'll use is {@link #newWakeLock(int, String) newWakeLock()}.
36  * This will create a {@link PowerManager.WakeLock} object.  You can then use methods
37  * on the wake lock object to control the power state of the device.
38  * </p><p>
39  * In practice it's quite simple:
40  * {@samplecode
41  * PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
42  * PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.SCREEN_DIM_WAKE_LOCK, "My Tag");
43  * wl.acquire();
44  *   ..screen will stay on during this section..
45  * wl.release();
46  * }
47  * </p><p>
48  * The following wake lock levels are defined, with varying effects on system power.
49  * <i>These levels are mutually exclusive - you may only specify one of them.</i>
50  *
51  * <table>
52  *     <tr><th>Flag Value</th>
53  *     <th>CPU</th> <th>Screen</th> <th>Keyboard</th></tr>
54  *
55  *     <tr><td>{@link #PARTIAL_WAKE_LOCK}</td>
56  *         <td>On*</td> <td>Off</td> <td>Off</td>
57  *     </tr>
58  *
59  *     <tr><td>{@link #SCREEN_DIM_WAKE_LOCK}</td>
60  *         <td>On</td> <td>Dim</td> <td>Off</td>
61  *     </tr>
62  *
63  *     <tr><td>{@link #SCREEN_BRIGHT_WAKE_LOCK}</td>
64  *         <td>On</td> <td>Bright</td> <td>Off</td>
65  *     </tr>
66  *
67  *     <tr><td>{@link #FULL_WAKE_LOCK}</td>
68  *         <td>On</td> <td>Bright</td> <td>Bright</td>
69  *     </tr>
70  * </table>
71  * </p><p>
72  * *<i>If you hold a partial wake lock, the CPU will continue to run, regardless of any
73  * display timeouts or the state of the screen and even after the user presses the power button.
74  * In all other wake locks, the CPU will run, but the user can still put the device to sleep
75  * using the power button.</i>
76  * </p><p>
77  * In addition, you can add two more flags, which affect behavior of the screen only.
78  * <i>These flags have no effect when combined with a {@link #PARTIAL_WAKE_LOCK}.</i></p>
79  *
80  * <table>
81  *     <tr><th>Flag Value</th> <th>Description</th></tr>
82  *
83  *     <tr><td>{@link #ACQUIRE_CAUSES_WAKEUP}</td>
84  *         <td>Normal wake locks don't actually turn on the illumination.  Instead, they cause
85  *         the illumination to remain on once it turns on (e.g. from user activity).  This flag
86  *         will force the screen and/or keyboard to turn on immediately, when the WakeLock is
87  *         acquired.  A typical use would be for notifications which are important for the user to
88  *         see immediately.</td>
89  *     </tr>
90  *
91  *     <tr><td>{@link #ON_AFTER_RELEASE}</td>
92  *         <td>If this flag is set, the user activity timer will be reset when the WakeLock is
93  *         released, causing the illumination to remain on a bit longer.  This can be used to
94  *         reduce flicker if you are cycling between wake lock conditions.</td>
95  *     </tr>
96  * </table>
97  * <p>
98  * Any application using a WakeLock must request the {@code android.permission.WAKE_LOCK}
99  * permission in an {@code &lt;uses-permission&gt;} element of the application's manifest.
100  * </p>
101  */
102 public final class PowerManager {
103     private static final String TAG = "PowerManager";
104 
105     /* NOTE: Wake lock levels were previously defined as a bit field, except that only a few
106      * combinations were actually supported so the bit field was removed.  This explains
107      * why the numbering scheme is so odd.  If adding a new wake lock level, any unused
108      * value can be used.
109      */
110 
111     /**
112      * Wake lock level: Ensures that the CPU is running; the screen and keyboard
113      * backlight will be allowed to go off.
114      * <p>
115      * If the user presses the power button, then the screen will be turned off
116      * but the CPU will be kept on until all partial wake locks have been released.
117      * </p>
118      */
119     public static final int PARTIAL_WAKE_LOCK = 0x00000001;
120 
121     /**
122      * Wake lock level: Ensures that the screen is on (but may be dimmed);
123      * the keyboard backlight will be allowed to go off.
124      * <p>
125      * If the user presses the power button, then the {@link #SCREEN_DIM_WAKE_LOCK} will be
126      * implicitly released by the system, causing both the screen and the CPU to be turned off.
127      * Contrast with {@link #PARTIAL_WAKE_LOCK}.
128      * </p>
129      *
130      * @deprecated Most applications should use
131      * {@link android.view.WindowManager.LayoutParams#FLAG_KEEP_SCREEN_ON} instead
132      * of this type of wake lock, as it will be correctly managed by the platform
133      * as the user moves between applications and doesn't require a special permission.
134      */
135     @Deprecated
136     public static final int SCREEN_DIM_WAKE_LOCK = 0x00000006;
137 
138     /**
139      * Wake lock level: Ensures that the screen is on at full brightness;
140      * the keyboard backlight will be allowed to go off.
141      * <p>
142      * If the user presses the power button, then the {@link #SCREEN_BRIGHT_WAKE_LOCK} will be
143      * implicitly released by the system, causing both the screen and the CPU to be turned off.
144      * Contrast with {@link #PARTIAL_WAKE_LOCK}.
145      * </p>
146      *
147      * @deprecated Most applications should use
148      * {@link android.view.WindowManager.LayoutParams#FLAG_KEEP_SCREEN_ON} instead
149      * of this type of wake lock, as it will be correctly managed by the platform
150      * as the user moves between applications and doesn't require a special permission.
151      */
152     @Deprecated
153     public static final int SCREEN_BRIGHT_WAKE_LOCK = 0x0000000a;
154 
155     /**
156      * Wake lock level: Ensures that the screen and keyboard backlight are on at
157      * full brightness.
158      * <p>
159      * If the user presses the power button, then the {@link #FULL_WAKE_LOCK} will be
160      * implicitly released by the system, causing both the screen and the CPU to be turned off.
161      * Contrast with {@link #PARTIAL_WAKE_LOCK}.
162      * </p>
163      *
164      * @deprecated Most applications should use
165      * {@link android.view.WindowManager.LayoutParams#FLAG_KEEP_SCREEN_ON} instead
166      * of this type of wake lock, as it will be correctly managed by the platform
167      * as the user moves between applications and doesn't require a special permission.
168      */
169     @Deprecated
170     public static final int FULL_WAKE_LOCK = 0x0000001a;
171 
172     /**
173      * Wake lock level: Turns the screen off when the proximity sensor activates.
174      * <p>
175      * If the proximity sensor detects that an object is nearby, the screen turns off
176      * immediately.  Shortly after the object moves away, the screen turns on again.
177      * </p><p>
178      * A proximity wake lock does not prevent the device from falling asleep
179      * unlike {@link #FULL_WAKE_LOCK}, {@link #SCREEN_BRIGHT_WAKE_LOCK} and
180      * {@link #SCREEN_DIM_WAKE_LOCK}.  If there is no user activity and no other
181      * wake locks are held, then the device will fall asleep (and lock) as usual.
182      * However, the device will not fall asleep while the screen has been turned off
183      * by the proximity sensor because it effectively counts as ongoing user activity.
184      * </p><p>
185      * Since not all devices have proximity sensors, use {@link #isWakeLockLevelSupported}
186      * to determine whether this wake lock level is supported.
187      * </p><p>
188      * Cannot be used with {@link #ACQUIRE_CAUSES_WAKEUP}.
189      * </p>
190      */
191     public static final int PROXIMITY_SCREEN_OFF_WAKE_LOCK = 0x00000020;
192 
193     /**
194      * Wake lock level: Put the screen in a low power state and allow the CPU to suspend
195      * if no other wake locks are held.
196      * <p>
197      * This is used by the dream manager to implement doze mode.  It currently
198      * has no effect unless the power manager is in the dozing state.
199      * </p><p>
200      * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
201      * </p>
202      *
203      * {@hide}
204      */
205     public static final int DOZE_WAKE_LOCK = 0x00000040;
206 
207     /**
208      * Mask for the wake lock level component of a combined wake lock level and flags integer.
209      *
210      * @hide
211      */
212     public static final int WAKE_LOCK_LEVEL_MASK = 0x0000ffff;
213 
214     /**
215      * Wake lock flag: Turn the screen on when the wake lock is acquired.
216      * <p>
217      * Normally wake locks don't actually wake the device, they just cause
218      * the screen to remain on once it's already on.  Think of the video player
219      * application as the normal behavior.  Notifications that pop up and want
220      * the device to be on are the exception; use this flag to be like them.
221      * </p><p>
222      * Cannot be used with {@link #PARTIAL_WAKE_LOCK}.
223      * </p>
224      */
225     public static final int ACQUIRE_CAUSES_WAKEUP = 0x10000000;
226 
227     /**
228      * Wake lock flag: When this wake lock is released, poke the user activity timer
229      * so the screen stays on for a little longer.
230      * <p>
231      * Will not turn the screen on if it is not already on.
232      * See {@link #ACQUIRE_CAUSES_WAKEUP} if you want that.
233      * </p><p>
234      * Cannot be used with {@link #PARTIAL_WAKE_LOCK}.
235      * </p>
236      */
237     public static final int ON_AFTER_RELEASE = 0x20000000;
238 
239     /**
240      * Wake lock flag: This wake lock is not important for logging events.  If a later
241      * wake lock is acquired that is important, it will be considered the one to log.
242      * @hide
243      */
244     public static final int UNIMPORTANT_FOR_LOGGING = 0x40000000;
245 
246     /**
247      * Flag for {@link WakeLock#release WakeLock.release(int)}: Defer releasing a
248      * {@link #PROXIMITY_SCREEN_OFF_WAKE_LOCK} wake lock until the proximity sensor
249      * indicates that an object is not in close proximity.
250      */
251     public static final int RELEASE_FLAG_WAIT_FOR_NO_PROXIMITY = 1;
252 
253     /**
254      * Brightness value for fully on.
255      * @hide
256      */
257     public static final int BRIGHTNESS_ON = 255;
258 
259     /**
260      * Brightness value for fully off.
261      * @hide
262      */
263     public static final int BRIGHTNESS_OFF = 0;
264 
265     /**
266      * Brightness value for default policy handling by the system.
267      * @hide
268      */
269     public static final int BRIGHTNESS_DEFAULT = -1;
270 
271     // Note: Be sure to update android.os.BatteryStats and PowerManager.h
272     // if adding or modifying user activity event constants.
273 
274     /**
275      * User activity event type: Unspecified event type.
276      * @hide
277      */
278     @SystemApi
279     public static final int USER_ACTIVITY_EVENT_OTHER = 0;
280 
281     /**
282      * User activity event type: Button or key pressed or released.
283      * @hide
284      */
285     @SystemApi
286     public static final int USER_ACTIVITY_EVENT_BUTTON = 1;
287 
288     /**
289      * User activity event type: Touch down, move or up.
290      * @hide
291      */
292     @SystemApi
293     public static final int USER_ACTIVITY_EVENT_TOUCH = 2;
294 
295     /**
296      * User activity flag: If already dimmed, extend the dim timeout
297      * but do not brighten.  This flag is useful for keeping the screen on
298      * a little longer without causing a visible change such as when
299      * the power key is pressed.
300      * @hide
301      */
302     @SystemApi
303     public static final int USER_ACTIVITY_FLAG_NO_CHANGE_LIGHTS = 1 << 0;
304 
305     /**
306      * User activity flag: Note the user activity as usual but do not
307      * reset the user activity timeout.  This flag is useful for applying
308      * user activity power hints when interacting with the device indirectly
309      * on a secondary screen while allowing the primary screen to go to sleep.
310      * @hide
311      */
312     @SystemApi
313     public static final int USER_ACTIVITY_FLAG_INDIRECT = 1 << 1;
314 
315     /**
316      * Go to sleep reason code: Going to sleep due by application request.
317      * @hide
318      */
319     public static final int GO_TO_SLEEP_REASON_APPLICATION = 0;
320 
321     /**
322      * Go to sleep reason code: Going to sleep due by request of the
323      * device administration policy.
324      * @hide
325      */
326     public static final int GO_TO_SLEEP_REASON_DEVICE_ADMIN = 1;
327 
328     /**
329      * Go to sleep reason code: Going to sleep due to a screen timeout.
330      * @hide
331      */
332     public static final int GO_TO_SLEEP_REASON_TIMEOUT = 2;
333 
334     /**
335      * Go to sleep reason code: Going to sleep due to the lid switch being closed.
336      * @hide
337      */
338     public static final int GO_TO_SLEEP_REASON_LID_SWITCH = 3;
339 
340     /**
341      * Go to sleep reason code: Going to sleep due to the power button being pressed.
342      * @hide
343      */
344     public static final int GO_TO_SLEEP_REASON_POWER_BUTTON = 4;
345 
346     /**
347      * Go to sleep reason code: Going to sleep due to HDMI.
348      * @hide
349      */
350     public static final int GO_TO_SLEEP_REASON_HDMI = 5;
351 
352     /**
353      * Go to sleep flag: Skip dozing state and directly go to full sleep.
354      * @hide
355      */
356     public static final int GO_TO_SLEEP_FLAG_NO_DOZE = 1 << 0;
357 
358     /**
359      * The value to pass as the 'reason' argument to reboot() to
360      * reboot into recovery mode (for applying system updates, doing
361      * factory resets, etc.).
362      * <p>
363      * Requires the {@link android.Manifest.permission#RECOVERY}
364      * permission (in addition to
365      * {@link android.Manifest.permission#REBOOT}).
366      * </p>
367      * @hide
368      */
369     public static final String REBOOT_RECOVERY = "recovery";
370 
371     final Context mContext;
372     final IPowerManager mService;
373     final Handler mHandler;
374 
375     /**
376      * {@hide}
377      */
PowerManager(Context context, IPowerManager service, Handler handler)378     public PowerManager(Context context, IPowerManager service, Handler handler) {
379         mContext = context;
380         mService = service;
381         mHandler = handler;
382     }
383 
384     /**
385      * Gets the minimum supported screen brightness setting.
386      * The screen may be allowed to become dimmer than this value but
387      * this is the minimum value that can be set by the user.
388      * @hide
389      */
getMinimumScreenBrightnessSetting()390     public int getMinimumScreenBrightnessSetting() {
391         return mContext.getResources().getInteger(
392                 com.android.internal.R.integer.config_screenBrightnessSettingMinimum);
393     }
394 
395     /**
396      * Gets the maximum supported screen brightness setting.
397      * The screen may be allowed to become dimmer than this value but
398      * this is the maximum value that can be set by the user.
399      * @hide
400      */
getMaximumScreenBrightnessSetting()401     public int getMaximumScreenBrightnessSetting() {
402         return mContext.getResources().getInteger(
403                 com.android.internal.R.integer.config_screenBrightnessSettingMaximum);
404     }
405 
406     /**
407      * Gets the default screen brightness setting.
408      * @hide
409      */
getDefaultScreenBrightnessSetting()410     public int getDefaultScreenBrightnessSetting() {
411         return mContext.getResources().getInteger(
412                 com.android.internal.R.integer.config_screenBrightnessSettingDefault);
413     }
414 
415     /**
416      * Returns true if the twilight service should be used to adjust screen brightness
417      * policy.  This setting is experimental and disabled by default.
418      * @hide
419      */
useTwilightAdjustmentFeature()420     public static boolean useTwilightAdjustmentFeature() {
421         return SystemProperties.getBoolean("persist.power.usetwilightadj", false);
422     }
423 
424     /**
425      * Creates a new wake lock with the specified level and flags.
426      * <p>
427      * The {@code levelAndFlags} parameter specifies a wake lock level and optional flags
428      * combined using the logical OR operator.
429      * </p><p>
430      * The wake lock levels are: {@link #PARTIAL_WAKE_LOCK},
431      * {@link #FULL_WAKE_LOCK}, {@link #SCREEN_DIM_WAKE_LOCK}
432      * and {@link #SCREEN_BRIGHT_WAKE_LOCK}.  Exactly one wake lock level must be
433      * specified as part of the {@code levelAndFlags} parameter.
434      * </p><p>
435      * The wake lock flags are: {@link #ACQUIRE_CAUSES_WAKEUP}
436      * and {@link #ON_AFTER_RELEASE}.  Multiple flags can be combined as part of the
437      * {@code levelAndFlags} parameters.
438      * </p><p>
439      * Call {@link WakeLock#acquire() acquire()} on the object to acquire the
440      * wake lock, and {@link WakeLock#release release()} when you are done.
441      * </p><p>
442      * {@samplecode
443      * PowerManager pm = (PowerManager)mContext.getSystemService(
444      *                                          Context.POWER_SERVICE);
445      * PowerManager.WakeLock wl = pm.newWakeLock(
446      *                                      PowerManager.SCREEN_DIM_WAKE_LOCK
447      *                                      | PowerManager.ON_AFTER_RELEASE,
448      *                                      TAG);
449      * wl.acquire();
450      * // ... do work...
451      * wl.release();
452      * }
453      * </p><p>
454      * Although a wake lock can be created without special permissions,
455      * the {@link android.Manifest.permission#WAKE_LOCK} permission is
456      * required to actually acquire or release the wake lock that is returned.
457      * </p><p class="note">
458      * If using this to keep the screen on, you should strongly consider using
459      * {@link android.view.WindowManager.LayoutParams#FLAG_KEEP_SCREEN_ON} instead.
460      * This window flag will be correctly managed by the platform
461      * as the user moves between applications and doesn't require a special permission.
462      * </p>
463      *
464      * @param levelAndFlags Combination of wake lock level and flag values defining
465      * the requested behavior of the WakeLock.
466      * @param tag Your class name (or other tag) for debugging purposes.
467      *
468      * @see WakeLock#acquire()
469      * @see WakeLock#release()
470      * @see #PARTIAL_WAKE_LOCK
471      * @see #FULL_WAKE_LOCK
472      * @see #SCREEN_DIM_WAKE_LOCK
473      * @see #SCREEN_BRIGHT_WAKE_LOCK
474      * @see #PROXIMITY_SCREEN_OFF_WAKE_LOCK
475      * @see #ACQUIRE_CAUSES_WAKEUP
476      * @see #ON_AFTER_RELEASE
477      */
newWakeLock(int levelAndFlags, String tag)478     public WakeLock newWakeLock(int levelAndFlags, String tag) {
479         validateWakeLockParameters(levelAndFlags, tag);
480         return new WakeLock(levelAndFlags, tag, mContext.getOpPackageName());
481     }
482 
483     /** @hide */
validateWakeLockParameters(int levelAndFlags, String tag)484     public static void validateWakeLockParameters(int levelAndFlags, String tag) {
485         switch (levelAndFlags & WAKE_LOCK_LEVEL_MASK) {
486             case PARTIAL_WAKE_LOCK:
487             case SCREEN_DIM_WAKE_LOCK:
488             case SCREEN_BRIGHT_WAKE_LOCK:
489             case FULL_WAKE_LOCK:
490             case PROXIMITY_SCREEN_OFF_WAKE_LOCK:
491             case DOZE_WAKE_LOCK:
492                 break;
493             default:
494                 throw new IllegalArgumentException("Must specify a valid wake lock level.");
495         }
496         if (tag == null) {
497             throw new IllegalArgumentException("The tag must not be null.");
498         }
499     }
500 
501     /**
502      * Notifies the power manager that user activity happened.
503      * <p>
504      * Resets the auto-off timer and brightens the screen if the device
505      * is not asleep.  This is what happens normally when a key or the touch
506      * screen is pressed or when some other user activity occurs.
507      * This method does not wake up the device if it has been put to sleep.
508      * </p><p>
509      * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
510      * </p>
511      *
512      * @param when The time of the user activity, in the {@link SystemClock#uptimeMillis()}
513      * time base.  This timestamp is used to correctly order the user activity request with
514      * other power management functions.  It should be set
515      * to the timestamp of the input event that caused the user activity.
516      * @param noChangeLights If true, does not cause the keyboard backlight to turn on
517      * because of this event.  This is set when the power key is pressed.
518      * We want the device to stay on while the button is down, but we're about
519      * to turn off the screen so we don't want the keyboard backlight to turn on again.
520      * Otherwise the lights flash on and then off and it looks weird.
521      *
522      * @see #wakeUp
523      * @see #goToSleep
524      *
525      * @removed Requires signature or system permission.
526      * @deprecated Use {@link #userActivity(long, int, int)}.
527      */
528     @Deprecated
userActivity(long when, boolean noChangeLights)529     public void userActivity(long when, boolean noChangeLights) {
530         userActivity(when, USER_ACTIVITY_EVENT_OTHER,
531                 noChangeLights ? USER_ACTIVITY_FLAG_NO_CHANGE_LIGHTS : 0);
532     }
533 
534     /**
535      * Notifies the power manager that user activity happened.
536      * <p>
537      * Resets the auto-off timer and brightens the screen if the device
538      * is not asleep.  This is what happens normally when a key or the touch
539      * screen is pressed or when some other user activity occurs.
540      * This method does not wake up the device if it has been put to sleep.
541      * </p><p>
542      * Requires the {@link android.Manifest.permission#DEVICE_POWER} or
543      * {@link android.Manifest.permission#USER_ACTIVITY} permission.
544      * </p>
545      *
546      * @param when The time of the user activity, in the {@link SystemClock#uptimeMillis()}
547      * time base.  This timestamp is used to correctly order the user activity request with
548      * other power management functions.  It should be set
549      * to the timestamp of the input event that caused the user activity.
550      * @param event The user activity event.
551      * @param flags Optional user activity flags.
552      *
553      * @see #wakeUp
554      * @see #goToSleep
555      *
556      * @hide Requires signature or system permission.
557      */
558     @SystemApi
userActivity(long when, int event, int flags)559     public void userActivity(long when, int event, int flags) {
560         try {
561             mService.userActivity(when, event, flags);
562         } catch (RemoteException e) {
563         }
564     }
565 
566    /**
567      * Forces the device to go to sleep.
568      * <p>
569      * Overrides all the wake locks that are held.
570      * This is what happens when the power key is pressed to turn off the screen.
571      * </p><p>
572      * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
573      * </p>
574      *
575      * @param time The time when the request to go to sleep was issued, in the
576      * {@link SystemClock#uptimeMillis()} time base.  This timestamp is used to correctly
577      * order the go to sleep request with other power management functions.  It should be set
578      * to the timestamp of the input event that caused the request to go to sleep.
579      *
580      * @see #userActivity
581      * @see #wakeUp
582      *
583      * @removed Requires signature permission.
584      */
goToSleep(long time)585     public void goToSleep(long time) {
586         goToSleep(time, GO_TO_SLEEP_REASON_APPLICATION, 0);
587     }
588 
589     /**
590      * Forces the device to go to sleep.
591      * <p>
592      * Overrides all the wake locks that are held.
593      * This is what happens when the power key is pressed to turn off the screen.
594      * </p><p>
595      * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
596      * </p>
597      *
598      * @param time The time when the request to go to sleep was issued, in the
599      * {@link SystemClock#uptimeMillis()} time base.  This timestamp is used to correctly
600      * order the go to sleep request with other power management functions.  It should be set
601      * to the timestamp of the input event that caused the request to go to sleep.
602      * @param reason The reason the device is going to sleep.
603      * @param flags Optional flags to apply when going to sleep.
604      *
605      * @see #userActivity
606      * @see #wakeUp
607      *
608      * @hide Requires signature permission.
609      */
goToSleep(long time, int reason, int flags)610     public void goToSleep(long time, int reason, int flags) {
611         try {
612             mService.goToSleep(time, reason, flags);
613         } catch (RemoteException e) {
614         }
615     }
616 
617     /**
618      * Forces the device to wake up from sleep.
619      * <p>
620      * If the device is currently asleep, wakes it up, otherwise does nothing.
621      * This is what happens when the power key is pressed to turn on the screen.
622      * </p><p>
623      * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
624      * </p>
625      *
626      * @param time The time when the request to wake up was issued, in the
627      * {@link SystemClock#uptimeMillis()} time base.  This timestamp is used to correctly
628      * order the wake up request with other power management functions.  It should be set
629      * to the timestamp of the input event that caused the request to wake up.
630      *
631      * @see #userActivity
632      * @see #goToSleep
633      *
634      * @removed Requires signature permission.
635      */
wakeUp(long time)636     public void wakeUp(long time) {
637         try {
638             mService.wakeUp(time);
639         } catch (RemoteException e) {
640         }
641     }
642 
643     /**
644      * Forces the device to start napping.
645      * <p>
646      * If the device is currently awake, starts dreaming, otherwise does nothing.
647      * When the dream ends or if the dream cannot be started, the device will
648      * either wake up or go to sleep depending on whether there has been recent
649      * user activity.
650      * </p><p>
651      * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
652      * </p>
653      *
654      * @param time The time when the request to nap was issued, in the
655      * {@link SystemClock#uptimeMillis()} time base.  This timestamp is used to correctly
656      * order the nap request with other power management functions.  It should be set
657      * to the timestamp of the input event that caused the request to nap.
658      *
659      * @see #wakeUp
660      * @see #goToSleep
661      *
662      * @hide Requires signature permission.
663      */
nap(long time)664     public void nap(long time) {
665         try {
666             mService.nap(time);
667         } catch (RemoteException e) {
668         }
669     }
670 
671     /**
672      * Boosts the brightness of the screen to maximum for a predetermined
673      * period of time.  This is used to make the screen more readable in bright
674      * daylight for a short duration.
675      * <p>
676      * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
677      * </p>
678      *
679      * @param time The time when the request to boost was issued, in the
680      * {@link SystemClock#uptimeMillis()} time base.  This timestamp is used to correctly
681      * order the boost request with other power management functions.  It should be set
682      * to the timestamp of the input event that caused the request to boost.
683      *
684      * @hide Requires signature permission.
685      */
boostScreenBrightness(long time)686     public void boostScreenBrightness(long time) {
687         try {
688             mService.boostScreenBrightness(time);
689         } catch (RemoteException e) {
690         }
691     }
692 
693     /**
694      * Sets the brightness of the backlights (screen, keyboard, button).
695      * <p>
696      * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
697      * </p>
698      *
699      * @param brightness The brightness value from 0 to 255.
700      *
701      * @hide Requires signature permission.
702      */
setBacklightBrightness(int brightness)703     public void setBacklightBrightness(int brightness) {
704         try {
705             mService.setTemporaryScreenBrightnessSettingOverride(brightness);
706         } catch (RemoteException e) {
707         }
708     }
709 
710    /**
711      * Returns true if the specified wake lock level is supported.
712      *
713      * @param level The wake lock level to check.
714      * @return True if the specified wake lock level is supported.
715      */
isWakeLockLevelSupported(int level)716     public boolean isWakeLockLevelSupported(int level) {
717         try {
718             return mService.isWakeLockLevelSupported(level);
719         } catch (RemoteException e) {
720             return false;
721         }
722     }
723 
724     /**
725       * Returns true if the device is in an interactive state.
726       * <p>
727       * For historical reasons, the name of this method refers to the power state of
728       * the screen but it actually describes the overall interactive state of
729       * the device.  This method has been replaced by {@link #isInteractive}.
730       * </p><p>
731       * The value returned by this method only indicates whether the device is
732       * in an interactive state which may have nothing to do with the screen being
733       * on or off.  To determine the actual state of the screen,
734       * use {@link android.view.Display#getState}.
735       * </p>
736       *
737       * @return True if the device is in an interactive state.
738       *
739       * @deprecated Use {@link #isInteractive} instead.
740       */
741     @Deprecated
isScreenOn()742     public boolean isScreenOn() {
743         return isInteractive();
744     }
745 
746     /**
747      * Returns true if the device is in an interactive state.
748      * <p>
749      * When this method returns true, the device is awake and ready to interact
750      * with the user (although this is not a guarantee that the user is actively
751      * interacting with the device just this moment).  The main screen is usually
752      * turned on while in this state.  Certain features, such as the proximity
753      * sensor, may temporarily turn off the screen while still leaving the device in an
754      * interactive state.  Note in particular that the device is still considered
755      * to be interactive while dreaming (since dreams can be interactive) but not
756      * when it is dozing or asleep.
757      * </p><p>
758      * When this method returns false, the device is dozing or asleep and must
759      * be awoken before it will become ready to interact with the user again.  The
760      * main screen is usually turned off while in this state.  Certain features,
761      * such as "ambient mode" may cause the main screen to remain on (albeit in a
762      * low power state) to display system-provided content while the device dozes.
763      * </p><p>
764      * The system will send a {@link android.content.Intent#ACTION_SCREEN_ON screen on}
765      * or {@link android.content.Intent#ACTION_SCREEN_OFF screen off} broadcast
766      * whenever the interactive state of the device changes.  For historical reasons,
767      * the names of these broadcasts refer to the power state of the screen
768      * but they are actually sent in response to changes in the overall interactive
769      * state of the device, as described by this method.
770      * </p><p>
771      * Services may use the non-interactive state as a hint to conserve power
772      * since the user is not present.
773      * </p>
774      *
775      * @return True if the device is in an interactive state.
776      *
777      * @see android.content.Intent#ACTION_SCREEN_ON
778      * @see android.content.Intent#ACTION_SCREEN_OFF
779      */
isInteractive()780     public boolean isInteractive() {
781         try {
782             return mService.isInteractive();
783         } catch (RemoteException e) {
784             return false;
785         }
786     }
787 
788     /**
789      * Reboot the device.  Will not return if the reboot is successful.
790      * <p>
791      * Requires the {@link android.Manifest.permission#REBOOT} permission.
792      * </p>
793      *
794      * @param reason code to pass to the kernel (e.g., "recovery") to
795      *               request special boot modes, or null.
796      */
reboot(String reason)797     public void reboot(String reason) {
798         try {
799             mService.reboot(false, reason, true);
800         } catch (RemoteException e) {
801         }
802     }
803 
804     /**
805      * Returns true if the device is currently in power save mode.  When in this mode,
806      * applications should reduce their functionality in order to conserve battery as
807      * much as possible.  You can monitor for changes to this state with
808      * {@link #ACTION_POWER_SAVE_MODE_CHANGED}.
809      *
810      * @return Returns true if currently in low power mode, else false.
811      */
isPowerSaveMode()812     public boolean isPowerSaveMode() {
813         try {
814             return mService.isPowerSaveMode();
815         } catch (RemoteException e) {
816             return false;
817         }
818     }
819 
820     /**
821      * Set the current power save mode.
822      *
823      * @return True if the set was allowed.
824      *
825      * @see #isPowerSaveMode()
826      *
827      * @hide
828      */
setPowerSaveMode(boolean mode)829     public boolean setPowerSaveMode(boolean mode) {
830         try {
831             return mService.setPowerSaveMode(mode);
832         } catch (RemoteException e) {
833             return false;
834         }
835     }
836 
837     /**
838      * Intent that is broadcast when the state of {@link #isPowerSaveMode()} changes.
839      * This broadcast is only sent to registered receivers.
840      */
841     @SdkConstant(SdkConstant.SdkConstantType.BROADCAST_INTENT_ACTION)
842     public static final String ACTION_POWER_SAVE_MODE_CHANGED
843             = "android.os.action.POWER_SAVE_MODE_CHANGED";
844 
845     /**
846      * Intent that is broadcast when the state of {@link #isPowerSaveMode()} is about to change.
847      * This broadcast is only sent to registered receivers.
848      *
849      * @hide
850      */
851     @SdkConstant(SdkConstant.SdkConstantType.BROADCAST_INTENT_ACTION)
852     public static final String ACTION_POWER_SAVE_MODE_CHANGING
853             = "android.os.action.POWER_SAVE_MODE_CHANGING";
854 
855     /** @hide */
856     public static final String EXTRA_POWER_SAVE_MODE = "mode";
857 
858     /**
859      * A wake lock is a mechanism to indicate that your application needs
860      * to have the device stay on.
861      * <p>
862      * Any application using a WakeLock must request the {@code android.permission.WAKE_LOCK}
863      * permission in an {@code &lt;uses-permission&gt;} element of the application's manifest.
864      * Obtain a wake lock by calling {@link PowerManager#newWakeLock(int, String)}.
865      * </p><p>
866      * Call {@link #acquire()} to acquire the wake lock and force the device to stay
867      * on at the level that was requested when the wake lock was created.
868      * </p><p>
869      * Call {@link #release()} when you are done and don't need the lock anymore.
870      * It is very important to do this as soon as possible to avoid running down the
871      * device's battery excessively.
872      * </p>
873      */
874     public final class WakeLock {
875         private int mFlags;
876         private String mTag;
877         private final String mPackageName;
878         private final IBinder mToken;
879         private int mCount;
880         private boolean mRefCounted = true;
881         private boolean mHeld;
882         private WorkSource mWorkSource;
883         private String mHistoryTag;
884         private final String mTraceName;
885 
886         private final Runnable mReleaser = new Runnable() {
887             public void run() {
888                 release();
889             }
890         };
891 
WakeLock(int flags, String tag, String packageName)892         WakeLock(int flags, String tag, String packageName) {
893             mFlags = flags;
894             mTag = tag;
895             mPackageName = packageName;
896             mToken = new Binder();
897             mTraceName = "WakeLock (" + mTag + ")";
898         }
899 
900         @Override
finalize()901         protected void finalize() throws Throwable {
902             synchronized (mToken) {
903                 if (mHeld) {
904                     Log.wtf(TAG, "WakeLock finalized while still held: " + mTag);
905                     Trace.asyncTraceEnd(Trace.TRACE_TAG_POWER, mTraceName, 0);
906                     try {
907                         mService.releaseWakeLock(mToken, 0);
908                     } catch (RemoteException e) {
909                     }
910                 }
911             }
912         }
913 
914         /**
915          * Sets whether this WakeLock is reference counted.
916          * <p>
917          * Wake locks are reference counted by default.  If a wake lock is
918          * reference counted, then each call to {@link #acquire()} must be
919          * balanced by an equal number of calls to {@link #release()}.  If a wake
920          * lock is not reference counted, then one call to {@link #release()} is
921          * sufficient to undo the effect of all previous calls to {@link #acquire()}.
922          * </p>
923          *
924          * @param value True to make the wake lock reference counted, false to
925          * make the wake lock non-reference counted.
926          */
setReferenceCounted(boolean value)927         public void setReferenceCounted(boolean value) {
928             synchronized (mToken) {
929                 mRefCounted = value;
930             }
931         }
932 
933         /**
934          * Acquires the wake lock.
935          * <p>
936          * Ensures that the device is on at the level requested when
937          * the wake lock was created.
938          * </p>
939          */
acquire()940         public void acquire() {
941             synchronized (mToken) {
942                 acquireLocked();
943             }
944         }
945 
946         /**
947          * Acquires the wake lock with a timeout.
948          * <p>
949          * Ensures that the device is on at the level requested when
950          * the wake lock was created.  The lock will be released after the given timeout
951          * expires.
952          * </p>
953          *
954          * @param timeout The timeout after which to release the wake lock, in milliseconds.
955          */
acquire(long timeout)956         public void acquire(long timeout) {
957             synchronized (mToken) {
958                 acquireLocked();
959                 mHandler.postDelayed(mReleaser, timeout);
960             }
961         }
962 
acquireLocked()963         private void acquireLocked() {
964             if (!mRefCounted || mCount++ == 0) {
965                 // Do this even if the wake lock is already thought to be held (mHeld == true)
966                 // because non-reference counted wake locks are not always properly released.
967                 // For example, the keyguard's wake lock might be forcibly released by the
968                 // power manager without the keyguard knowing.  A subsequent call to acquire
969                 // should immediately acquire the wake lock once again despite never having
970                 // been explicitly released by the keyguard.
971                 mHandler.removeCallbacks(mReleaser);
972                 Trace.asyncTraceBegin(Trace.TRACE_TAG_POWER, mTraceName, 0);
973                 try {
974                     mService.acquireWakeLock(mToken, mFlags, mTag, mPackageName, mWorkSource,
975                             mHistoryTag);
976                 } catch (RemoteException e) {
977                 }
978                 mHeld = true;
979             }
980         }
981 
982         /**
983          * Releases the wake lock.
984          * <p>
985          * This method releases your claim to the CPU or screen being on.
986          * The screen may turn off shortly after you release the wake lock, or it may
987          * not if there are other wake locks still held.
988          * </p>
989          */
release()990         public void release() {
991             release(0);
992         }
993 
994         /**
995          * Releases the wake lock with flags to modify the release behavior.
996          * <p>
997          * This method releases your claim to the CPU or screen being on.
998          * The screen may turn off shortly after you release the wake lock, or it may
999          * not if there are other wake locks still held.
1000          * </p>
1001          *
1002          * @param flags Combination of flag values to modify the release behavior.
1003          * Currently only {@link #RELEASE_FLAG_WAIT_FOR_NO_PROXIMITY} is supported.
1004          * Passing 0 is equivalent to calling {@link #release()}.
1005          */
release(int flags)1006         public void release(int flags) {
1007             synchronized (mToken) {
1008                 if (!mRefCounted || --mCount == 0) {
1009                     mHandler.removeCallbacks(mReleaser);
1010                     if (mHeld) {
1011                         Trace.asyncTraceEnd(Trace.TRACE_TAG_POWER, mTraceName, 0);
1012                         try {
1013                             mService.releaseWakeLock(mToken, flags);
1014                         } catch (RemoteException e) {
1015                         }
1016                         mHeld = false;
1017                     }
1018                 }
1019                 if (mCount < 0) {
1020                     throw new RuntimeException("WakeLock under-locked " + mTag);
1021                 }
1022             }
1023         }
1024 
1025         /**
1026          * Returns true if the wake lock has been acquired but not yet released.
1027          *
1028          * @return True if the wake lock is held.
1029          */
isHeld()1030         public boolean isHeld() {
1031             synchronized (mToken) {
1032                 return mHeld;
1033             }
1034         }
1035 
1036         /**
1037          * Sets the work source associated with the wake lock.
1038          * <p>
1039          * The work source is used to determine on behalf of which application
1040          * the wake lock is being held.  This is useful in the case where a
1041          * service is performing work on behalf of an application so that the
1042          * cost of that work can be accounted to the application.
1043          * </p>
1044          *
1045          * @param ws The work source, or null if none.
1046          */
setWorkSource(WorkSource ws)1047         public void setWorkSource(WorkSource ws) {
1048             synchronized (mToken) {
1049                 if (ws != null && ws.size() == 0) {
1050                     ws = null;
1051                 }
1052 
1053                 final boolean changed;
1054                 if (ws == null) {
1055                     changed = mWorkSource != null;
1056                     mWorkSource = null;
1057                 } else if (mWorkSource == null) {
1058                     changed = true;
1059                     mWorkSource = new WorkSource(ws);
1060                 } else {
1061                     changed = mWorkSource.diff(ws);
1062                     if (changed) {
1063                         mWorkSource.set(ws);
1064                     }
1065                 }
1066 
1067                 if (changed && mHeld) {
1068                     try {
1069                         mService.updateWakeLockWorkSource(mToken, mWorkSource, mHistoryTag);
1070                     } catch (RemoteException e) {
1071                     }
1072                 }
1073             }
1074         }
1075 
1076         /** @hide */
setTag(String tag)1077         public void setTag(String tag) {
1078             mTag = tag;
1079         }
1080 
1081         /** @hide */
setHistoryTag(String tag)1082         public void setHistoryTag(String tag) {
1083             mHistoryTag = tag;
1084         }
1085 
1086         /** @hide */
setUnimportantForLogging(boolean state)1087         public void setUnimportantForLogging(boolean state) {
1088             if (state) mFlags |= UNIMPORTANT_FOR_LOGGING;
1089             else mFlags &= ~UNIMPORTANT_FOR_LOGGING;
1090         }
1091 
1092         @Override
toString()1093         public String toString() {
1094             synchronized (mToken) {
1095                 return "WakeLock{"
1096                     + Integer.toHexString(System.identityHashCode(this))
1097                     + " held=" + mHeld + ", refCount=" + mCount + "}";
1098             }
1099         }
1100     }
1101 }
1102