1 /*
2  * Copyright (C) 2014 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.hardware.display;
18 
19 import android.annotation.IntDef;
20 import android.annotation.Nullable;
21 import android.graphics.Point;
22 import android.hardware.SensorManager;
23 import android.os.Handler;
24 import android.os.IBinder;
25 import android.os.PowerManager;
26 import android.util.IntArray;
27 import android.util.Slog;
28 import android.util.SparseArray;
29 import android.view.Display;
30 import android.view.DisplayInfo;
31 import android.view.SurfaceControl;
32 import android.view.SurfaceControl.Transaction;
33 
34 import java.lang.annotation.Retention;
35 import java.lang.annotation.RetentionPolicy;
36 import java.util.List;
37 import java.util.Objects;
38 
39 /**
40  * Display manager local system service interface.
41  *
42  * @hide Only for use within the system server.
43  */
44 public abstract class DisplayManagerInternal {
45 
46     @IntDef(prefix = {"REFRESH_RATE_LIMIT_"}, value = {
47             REFRESH_RATE_LIMIT_HIGH_BRIGHTNESS_MODE
48     })
49     @Retention(RetentionPolicy.SOURCE)
50     public @interface RefreshRateLimitType {}
51 
52     /** Refresh rate should be limited when High Brightness Mode is active. */
53     public static final int REFRESH_RATE_LIMIT_HIGH_BRIGHTNESS_MODE = 1;
54 
55     /**
56      * Called by the power manager to initialize power management facilities.
57      */
initPowerManagement(DisplayPowerCallbacks callbacks, Handler handler, SensorManager sensorManager)58     public abstract void initPowerManagement(DisplayPowerCallbacks callbacks,
59             Handler handler, SensorManager sensorManager);
60 
61     /**
62      * Called by the power manager to request a new power state.
63      * <p>
64      * The display power controller makes a copy of the provided object and then
65      * begins adjusting the power state to match what was requested.
66      * </p>
67      *
68      * @param groupId The identifier for the display group being requested to change power state
69      * @param request The requested power state.
70      * @param waitForNegativeProximity If {@code true}, issues a request to wait for
71      * negative proximity before turning the screen back on, assuming the screen
72      * was turned off by the proximity sensor.
73      * @return {@code true} if display group is ready, {@code false} if there are important
74      * changes that must be made asynchronously (such as turning the screen on), in which case
75      * the caller should grab a wake lock, watch for {@link DisplayPowerCallbacks#onStateChanged}
76      * then try the request again later until the state converges. If the provided {@code groupId}
77      * cannot be found then {@code true} will be returned.
78      */
requestPowerState(int groupId, DisplayPowerRequest request, boolean waitForNegativeProximity)79     public abstract boolean requestPowerState(int groupId, DisplayPowerRequest request,
80             boolean waitForNegativeProximity);
81 
82     /**
83      * Returns {@code true} if the proximity sensor screen-off function is available.
84      */
isProximitySensorAvailable()85     public abstract boolean isProximitySensorAvailable();
86 
87     /**
88      * Registers a display group listener which will be informed of the addition, removal, or change
89      * of display groups.
90      *
91      * @param listener The listener to register.
92      */
registerDisplayGroupListener(DisplayGroupListener listener)93     public abstract void registerDisplayGroupListener(DisplayGroupListener listener);
94 
95     /**
96      * Unregisters a display group listener which will be informed of the addition, removal, or
97      * change of display groups.
98      *
99      * @param listener The listener to unregister.
100      */
unregisterDisplayGroupListener(DisplayGroupListener listener)101     public abstract void unregisterDisplayGroupListener(DisplayGroupListener listener);
102 
103     /**
104      * Screenshot for internal system-only use such as rotation, etc.  This method includes
105      * secure layers and the result should never be exposed to non-system applications.
106      * This method does not apply any rotation and provides the output in natural orientation.
107      *
108      * @param displayId The display id to take the screenshot of.
109      * @return The buffer or null if we have failed.
110      */
systemScreenshot(int displayId)111     public abstract SurfaceControl.ScreenshotHardwareBuffer systemScreenshot(int displayId);
112 
113     /**
114      * General screenshot functionality that excludes secure layers and applies appropriate
115      * rotation that the device is currently in.
116      *
117      * @param displayId The display id to take the screenshot of.
118      * @return The buffer or null if we have failed.
119      */
userScreenshot(int displayId)120     public abstract SurfaceControl.ScreenshotHardwareBuffer userScreenshot(int displayId);
121 
122     /**
123      * Returns information about the specified logical display.
124      *
125      * @param displayId The logical display id.
126      * @return The logical display info, or null if the display does not exist.  The
127      * returned object must be treated as immutable.
128      */
getDisplayInfo(int displayId)129     public abstract DisplayInfo getDisplayInfo(int displayId);
130 
131     /**
132      * Returns the position of the display's projection.
133      *
134      * @param displayId The logical display id.
135      * @return The x, y coordinates of the display, or null if the display does not exist. The
136      * return object must be treated as immutable.
137      */
138     @Nullable
getDisplayPosition(int displayId)139     public abstract Point getDisplayPosition(int displayId);
140 
141     /**
142      * Registers a display transaction listener to provide the client a chance to
143      * update its surfaces within the same transaction as any display layout updates.
144      *
145      * @param listener The listener to register.
146      */
registerDisplayTransactionListener(DisplayTransactionListener listener)147     public abstract void registerDisplayTransactionListener(DisplayTransactionListener listener);
148 
149     /**
150      * Unregisters a display transaction listener to provide the client a chance to
151      * update its surfaces within the same transaction as any display layout updates.
152      *
153      * @param listener The listener to unregister.
154      */
unregisterDisplayTransactionListener(DisplayTransactionListener listener)155     public abstract void unregisterDisplayTransactionListener(DisplayTransactionListener listener);
156 
157     /**
158      * Overrides the display information of a particular logical display.
159      * This is used by the window manager to control the size and characteristics
160      * of the default display.  It is expected to apply the requested change
161      * to the display information synchronously so that applications will immediately
162      * observe the new state.
163      *
164      * NOTE: This method must be the only entry point by which the window manager
165      * influences the logical configuration of displays.
166      *
167      * @param displayId The logical display id.
168      * @param info The new data to be stored.
169      */
setDisplayInfoOverrideFromWindowManager( int displayId, DisplayInfo info)170     public abstract void setDisplayInfoOverrideFromWindowManager(
171             int displayId, DisplayInfo info);
172 
173     /**
174      * Get current display info without override from WindowManager.
175      * Current implementation of LogicalDisplay#getDisplayInfoLocked() always returns display info
176      * with overrides from WM if set. This method can be used for getting real display size without
177      * overrides to determine if real changes to display metrics happened.
178      * @param displayId Id of the target display.
179      * @param outInfo {@link DisplayInfo} to fill.
180      */
getNonOverrideDisplayInfo(int displayId, DisplayInfo outInfo)181     public abstract void getNonOverrideDisplayInfo(int displayId, DisplayInfo outInfo);
182 
183     /**
184      * Called by the window manager to perform traversals while holding a
185      * surface flinger transaction.
186      */
performTraversal(Transaction t)187     public abstract void performTraversal(Transaction t);
188 
189     /**
190      * Tells the display manager about properties of the display that depend on the windows on it.
191      * This includes whether there is interesting unique content on the specified logical display,
192      * and whether the one of the windows has a preferred refresh rate.
193      * <p>
194      * If the display has unique content, then the display manager arranges for it
195      * to be presented on a physical display if appropriate.  Otherwise, the display manager
196      * may choose to make the physical display mirror some other logical display.
197      * </p>
198      *
199      * <p>
200      * If one of the windows on the display has a preferred refresh rate that's supported by the
201      * display, then the display manager will request its use.
202      * </p>
203      *
204      * @param displayId The logical display id to update.
205      * @param hasContent True if the logical display has content. This is used to control automatic
206      * mirroring.
207      * @param requestedRefreshRate The preferred refresh rate for the top-most visible window that
208      * has a preference.
209      * @param requestedModeId The preferred mode id for the top-most visible window that has a
210      * preference.
211      * @param requestedMinRefreshRate The preferred lowest refresh rate for the top-most visible
212      *                                window that has a preference.
213      * @param requestedMaxRefreshRate The preferred highest refresh rate for the top-most visible
214      *                                window that has a preference.
215      * @param requestedMinimalPostProcessing The preferred minimal post processing setting for the
216      * display. This is true when there is at least one visible window that wants minimal post
217      * processng on.
218      * @param inTraversal True if called from WindowManagerService during a window traversal
219      * prior to call to performTraversalInTransactionFromWindowManager.
220      */
setDisplayProperties(int displayId, boolean hasContent, float requestedRefreshRate, int requestedModeId, float requestedMinRefreshRate, float requestedMaxRefreshRate, boolean requestedMinimalPostProcessing, boolean inTraversal)221     public abstract void setDisplayProperties(int displayId, boolean hasContent,
222             float requestedRefreshRate, int requestedModeId, float requestedMinRefreshRate,
223             float requestedMaxRefreshRate, boolean requestedMinimalPostProcessing,
224             boolean inTraversal);
225 
226     /**
227      * Applies an offset to the contents of a display, for example to avoid burn-in.
228      * <p>
229      * TODO: Technically this should be associated with a physical rather than logical
230      * display but this is good enough for now.
231      * </p>
232      *
233      * @param displayId The logical display id to update.
234      * @param x The X offset by which to shift the contents of the display.
235      * @param y The Y offset by which to shift the contents of the display.
236      */
setDisplayOffsets(int displayId, int x, int y)237     public abstract void setDisplayOffsets(int displayId, int x, int y);
238 
239     /**
240      * Disables scaling for a display.
241      *
242      * @param displayId The logical display id to disable scaling for.
243      * @param disableScaling {@code true} to disable scaling,
244      * {@code false} to use the default scaling behavior of the logical display.
245      */
setDisplayScalingDisabled(int displayId, boolean disableScaling)246     public abstract void setDisplayScalingDisabled(int displayId, boolean disableScaling);
247 
248     /**
249      * Provide a list of UIDs that are present on the display and are allowed to access it.
250      *
251      * @param displayAccessUIDs Mapping displayId -> int array of UIDs.
252      */
setDisplayAccessUIDs(SparseArray<IntArray> displayAccessUIDs)253     public abstract void setDisplayAccessUIDs(SparseArray<IntArray> displayAccessUIDs);
254 
255     /**
256      * Persist brightness slider events and ambient brightness stats.
257      */
persistBrightnessTrackerState()258     public abstract void persistBrightnessTrackerState();
259 
260     /**
261      * Notifies the display manager that resource overlays have changed.
262      */
onOverlayChanged()263     public abstract void onOverlayChanged();
264 
265     /**
266      * Get the attributes available for display color sampling.
267      * @param displayId id of the display to collect the sample from.
268      *
269      * @return The attributes the display supports, or null if sampling is not supported.
270      */
271     @Nullable
getDisplayedContentSamplingAttributes( int displayId)272     public abstract DisplayedContentSamplingAttributes getDisplayedContentSamplingAttributes(
273             int displayId);
274 
275     /**
276      * Enable or disable the collection of color samples.
277      *
278      * @param displayId id of the display to collect the sample from.
279      * @param componentMask a bitmask of the color channels to collect samples for, or zero for all
280      *                      available.
281      * @param maxFrames maintain a ringbuffer of the last maxFrames.
282      * @param enable True to enable, False to disable.
283      *
284      * @return True if sampling was enabled, false if failure.
285      */
setDisplayedContentSamplingEnabled( int displayId, boolean enable, int componentMask, int maxFrames)286     public abstract boolean setDisplayedContentSamplingEnabled(
287             int displayId, boolean enable, int componentMask, int maxFrames);
288 
289     /**
290      * Accesses the color histogram statistics of displayed frames on devices that support sampling.
291      *
292      * @param displayId id of the display to collect the sample from
293      * @param maxFrames limit the statistics to the last maxFrames number of frames.
294      * @param timestamp discard statistics that were collected prior to timestamp, where timestamp
295      *                  is given as CLOCK_MONOTONIC.
296      * @return The statistics representing a histogram of the color distribution of the frames
297      *         displayed on-screen, or null if sampling is not supported.
298     */
299     @Nullable
getDisplayedContentSample( int displayId, long maxFrames, long timestamp)300     public abstract DisplayedContentSample getDisplayedContentSample(
301             int displayId, long maxFrames, long timestamp);
302 
303     /**
304      * Temporarily ignore proximity-sensor-based display behavior until there is a change
305      * to the proximity sensor state. This allows the display to turn back on even if something
306      * is obstructing the proximity sensor.
307      */
ignoreProximitySensorUntilChanged()308     public abstract void ignoreProximitySensorUntilChanged();
309 
310     /**
311      * Returns the refresh rate switching type.
312      */
313     @DisplayManager.SwitchingType
getRefreshRateSwitchingType()314     public abstract int getRefreshRateSwitchingType();
315 
316     /**
317      * TODO: b/191384041 - Replace this with getRefreshRateLimitations()
318      * Return the refresh rate restriction for the specified display and sensor pairing. If the
319      * specified sensor is identified as an associated sensor in the specified display's
320      * display-device-config file, then return any refresh rate restrictions that it might define.
321      * If no restriction is specified, or the sensor is not associated with the display, then null
322      * will be returned.
323      *
324      * @param displayId The display to check against.
325      * @param name The name of the sensor.
326      * @param type The type of sensor.
327      *
328      * @return The min/max refresh-rate restriction as a {@link Pair} of floats, or null if not
329      * restricted.
330      */
getRefreshRateForDisplayAndSensor( int displayId, String name, String type)331     public abstract RefreshRateRange getRefreshRateForDisplayAndSensor(
332             int displayId, String name, String type);
333 
334     /**
335      * Returns a list of various refresh rate limitations for the specified display.
336      *
337      * @param displayId The display to get limitations for.
338      *
339      * @return a list of {@link RefreshRateLimitation}s describing the various limits.
340      */
getRefreshRateLimitations(int displayId)341     public abstract List<RefreshRateLimitation> getRefreshRateLimitations(int displayId);
342 
343     /**
344      * Returns the window token of the level of the WindowManager hierarchy to mirror. Returns null
345      * if layer mirroring by SurfaceFlinger should not be performed for the given displayId.
346      * For now, only used for mirroring started from MediaProjection.
347      */
getWindowTokenClientToMirror(int displayId)348     public abstract IBinder getWindowTokenClientToMirror(int displayId);
349 
350     /**
351      * For the given displayId, updates the window token of the level of the WindowManager hierarchy
352      * to mirror. If windowToken is null, then SurfaceFlinger performs no layer mirroring to the
353      * given display.
354      * For now, only used for mirroring started from MediaProjection.
355      */
setWindowTokenClientToMirror(int displayId, IBinder windowToken)356     public abstract void setWindowTokenClientToMirror(int displayId, IBinder windowToken);
357 
358     /**
359      * Returns the default size of the surface associated with the display, or null if the surface
360      * is not provided for layer mirroring by SurfaceFlinger.
361      * For now, only used for mirroring started from MediaProjection.
362      */
getDisplaySurfaceDefaultSize(int displayId)363     public abstract Point getDisplaySurfaceDefaultSize(int displayId);
364 
365     /**
366      * Describes the requested power state of the display.
367      *
368      * This object is intended to describe the general characteristics of the
369      * power state, such as whether the screen should be on or off and the current
370      * brightness controls leaving the DisplayPowerController to manage the
371      * details of how the transitions between states should occur.  The goal is for
372      * the PowerManagerService to focus on the global power state and not
373      * have to micro-manage screen off animations, auto-brightness and other effects.
374      */
375     public static final class DisplayPowerRequest {
376         // Policy: Turn screen off as if the user pressed the power button
377         // including playing a screen off animation if applicable.
378         public static final int POLICY_OFF = 0;
379         // Policy: Enable dozing and always-on display functionality.
380         public static final int POLICY_DOZE = 1;
381         // Policy: Make the screen dim when the user activity timeout is
382         // about to expire.
383         public static final int POLICY_DIM = 2;
384         // Policy: Make the screen bright as usual.
385         public static final int POLICY_BRIGHT = 3;
386         // Policy: Keep the screen and display optimized for VR mode.
387         public static final int POLICY_VR = 4;
388 
389         // The basic overall policy to apply: off, doze, dim or bright.
390         public int policy;
391 
392         // If true, the proximity sensor overrides the screen state when an object is
393         // nearby, turning it off temporarily until the object is moved away.
394         public boolean useProximitySensor;
395 
396         // An override of the screen brightness.
397         // Set to PowerManager.BRIGHTNESS_INVALID if there's no override.
398         public float screenBrightnessOverride;
399 
400         // An override of the screen auto-brightness adjustment factor in the range -1 (dimmer) to
401         // 1 (brighter). Set to Float.NaN if there's no override.
402         public float screenAutoBrightnessAdjustmentOverride;
403 
404         // If true, enables automatic brightness control.
405         public boolean useAutoBrightness;
406 
407         // If true, scales the brightness to a fraction of desired (as defined by
408         // screenLowPowerBrightnessFactor).
409         public boolean lowPowerMode;
410 
411         // The factor to adjust the screen brightness in low power mode in the range
412         // 0 (screen off) to 1 (no change)
413         public float screenLowPowerBrightnessFactor;
414 
415         // If true, applies a brightness boost.
416         public boolean boostScreenBrightness;
417 
418         // If true, prevents the screen from completely turning on if it is currently off.
419         // The display does not enter a "ready" state if this flag is true and screen on is
420         // blocked.  The window manager policy blocks screen on while it prepares the keyguard to
421         // prevent the user from seeing intermediate updates.
422         //
423         // Technically, we may not block the screen itself from turning on (because that introduces
424         // extra unnecessary latency) but we do prevent content on screen from becoming
425         // visible to the user.
426         public boolean blockScreenOn;
427 
428         // Overrides the policy for adjusting screen brightness and state while dozing.
429         public int dozeScreenState;
430         public float dozeScreenBrightness;
431 
DisplayPowerRequest()432         public DisplayPowerRequest() {
433             policy = POLICY_BRIGHT;
434             useProximitySensor = false;
435             screenBrightnessOverride = PowerManager.BRIGHTNESS_INVALID_FLOAT;
436             useAutoBrightness = false;
437             screenAutoBrightnessAdjustmentOverride = Float.NaN;
438             screenLowPowerBrightnessFactor = 0.5f;
439             blockScreenOn = false;
440             dozeScreenBrightness = PowerManager.BRIGHTNESS_INVALID_FLOAT;
441             dozeScreenState = Display.STATE_UNKNOWN;
442         }
443 
DisplayPowerRequest(DisplayPowerRequest other)444         public DisplayPowerRequest(DisplayPowerRequest other) {
445             copyFrom(other);
446         }
447 
isBrightOrDim()448         public boolean isBrightOrDim() {
449             return policy == POLICY_BRIGHT || policy == POLICY_DIM;
450         }
451 
isVr()452         public boolean isVr() {
453             return policy == POLICY_VR;
454         }
455 
copyFrom(DisplayPowerRequest other)456         public void copyFrom(DisplayPowerRequest other) {
457             policy = other.policy;
458             useProximitySensor = other.useProximitySensor;
459             screenBrightnessOverride = other.screenBrightnessOverride;
460             useAutoBrightness = other.useAutoBrightness;
461             screenAutoBrightnessAdjustmentOverride = other.screenAutoBrightnessAdjustmentOverride;
462             screenLowPowerBrightnessFactor = other.screenLowPowerBrightnessFactor;
463             blockScreenOn = other.blockScreenOn;
464             lowPowerMode = other.lowPowerMode;
465             boostScreenBrightness = other.boostScreenBrightness;
466             dozeScreenBrightness = other.dozeScreenBrightness;
467             dozeScreenState = other.dozeScreenState;
468         }
469 
470         @Override
equals(@ullable Object o)471         public boolean equals(@Nullable Object o) {
472             return o instanceof DisplayPowerRequest
473                     && equals((DisplayPowerRequest)o);
474         }
475 
equals(DisplayPowerRequest other)476         public boolean equals(DisplayPowerRequest other) {
477             return other != null
478                     && policy == other.policy
479                     && useProximitySensor == other.useProximitySensor
480                     && floatEquals(screenBrightnessOverride,
481                             other.screenBrightnessOverride)
482                     && useAutoBrightness == other.useAutoBrightness
483                     && floatEquals(screenAutoBrightnessAdjustmentOverride,
484                             other.screenAutoBrightnessAdjustmentOverride)
485                     && screenLowPowerBrightnessFactor
486                     == other.screenLowPowerBrightnessFactor
487                     && blockScreenOn == other.blockScreenOn
488                     && lowPowerMode == other.lowPowerMode
489                     && boostScreenBrightness == other.boostScreenBrightness
490                     && floatEquals(dozeScreenBrightness, other.dozeScreenBrightness)
491                     && dozeScreenState == other.dozeScreenState;
492         }
493 
floatEquals(float f1, float f2)494         private boolean floatEquals(float f1, float f2) {
495             return f1 == f2 || Float.isNaN(f1) && Float.isNaN(f2);
496         }
497 
498         @Override
hashCode()499         public int hashCode() {
500             return 0; // don't care
501         }
502 
503         @Override
toString()504         public String toString() {
505             return "policy=" + policyToString(policy)
506                     + ", useProximitySensor=" + useProximitySensor
507                     + ", screenBrightnessOverride=" + screenBrightnessOverride
508                     + ", useAutoBrightness=" + useAutoBrightness
509                     + ", screenAutoBrightnessAdjustmentOverride="
510                     + screenAutoBrightnessAdjustmentOverride
511                     + ", screenLowPowerBrightnessFactor=" + screenLowPowerBrightnessFactor
512                     + ", blockScreenOn=" + blockScreenOn
513                     + ", lowPowerMode=" + lowPowerMode
514                     + ", boostScreenBrightness=" + boostScreenBrightness
515                     + ", dozeScreenBrightness=" + dozeScreenBrightness
516                     + ", dozeScreenState=" + Display.stateToString(dozeScreenState);
517         }
518 
policyToString(int policy)519         public static String policyToString(int policy) {
520             switch (policy) {
521                 case POLICY_OFF:
522                     return "OFF";
523                 case POLICY_DOZE:
524                     return "DOZE";
525                 case POLICY_DIM:
526                     return "DIM";
527                 case POLICY_BRIGHT:
528                     return "BRIGHT";
529                 case POLICY_VR:
530                     return "VR";
531                 default:
532                     return Integer.toString(policy);
533             }
534         }
535     }
536 
537     /**
538      * Asynchronous callbacks from the power controller to the power manager service.
539      */
540     public interface DisplayPowerCallbacks {
onStateChanged()541         void onStateChanged();
onProximityPositive()542         void onProximityPositive();
onProximityNegative()543         void onProximityNegative();
onDisplayStateChange(boolean allInactive, boolean allOff)544         void onDisplayStateChange(boolean allInactive, boolean allOff);
545 
acquireSuspendBlocker()546         void acquireSuspendBlocker();
releaseSuspendBlocker()547         void releaseSuspendBlocker();
548     }
549 
550     /**
551      * Called within a Surface transaction whenever the size or orientation of a
552      * display may have changed.  Provides an opportunity for the client to
553      * update the position of its surfaces as part of the same transaction.
554      */
555     public interface DisplayTransactionListener {
onDisplayTransaction(Transaction t)556         void onDisplayTransaction(Transaction t);
557     }
558 
559     /**
560      * Called when there are changes to {@link com.android.server.display.DisplayGroup
561      * DisplayGroups}.
562      */
563     public interface DisplayGroupListener {
564         /**
565          * A new display group with the provided {@code groupId} was added.
566          *
567          * <ol>
568          *     <li>The {@code groupId} is applied to all appropriate {@link Display displays}.
569          *     <li>This method is called.
570          *     <li>{@link android.hardware.display.DisplayManager.DisplayListener DisplayListeners}
571          *     are informed of any corresponding changes.
572          * </ol>
573          */
onDisplayGroupAdded(int groupId)574         void onDisplayGroupAdded(int groupId);
575 
576         /**
577          * The display group with the provided {@code groupId} was removed.
578          *
579          * <ol>
580          *     <li>All affected {@link Display displays} have their group IDs updated appropriately.
581          *     <li>{@link android.hardware.display.DisplayManager.DisplayListener DisplayListeners}
582          *     are informed of any corresponding changes.
583          *     <li>This method is called.
584          * </ol>
585          */
onDisplayGroupRemoved(int groupId)586         void onDisplayGroupRemoved(int groupId);
587 
588         /**
589          * The display group with the provided {@code groupId} has changed.
590          *
591          * <ol>
592          *     <li>All affected {@link Display displays} have their group IDs updated appropriately.
593          *     <li>{@link android.hardware.display.DisplayManager.DisplayListener DisplayListeners}
594          *     are informed of any corresponding changes.
595          *     <li>This method is called.
596          * </ol>
597          */
onDisplayGroupChanged(int groupId)598         void onDisplayGroupChanged(int groupId);
599     }
600 
601     /**
602      * Information about the min and max refresh rate DM would like to set the display to.
603      */
604     public static final class RefreshRateRange {
605         public static final String TAG = "RefreshRateRange";
606 
607         // The tolerance within which we consider something approximately equals.
608         public static final float FLOAT_TOLERANCE = 0.01f;
609 
610         /**
611          * The lowest desired refresh rate.
612          */
613         public float min;
614 
615         /**
616          * The highest desired refresh rate.
617          */
618         public float max;
619 
RefreshRateRange()620         public RefreshRateRange() {}
621 
RefreshRateRange(float min, float max)622         public RefreshRateRange(float min, float max) {
623             if (min < 0 || max < 0 || min > max + FLOAT_TOLERANCE) {
624                 Slog.e(TAG, "Wrong values for min and max when initializing RefreshRateRange : "
625                         + min + " " + max);
626                 this.min = this.max = 0;
627                 return;
628             }
629             if (min > max) {
630                 // Min and max are within epsilon of each other, but in the wrong order.
631                 float t = min;
632                 min = max;
633                 max = t;
634             }
635             this.min = min;
636             this.max = max;
637         }
638 
639         /**
640          * Checks whether the two objects have the same values.
641          */
642         @Override
equals(Object other)643         public boolean equals(Object other) {
644             if (other == this) {
645                 return true;
646             }
647 
648             if (!(other instanceof RefreshRateRange)) {
649                 return false;
650             }
651 
652             RefreshRateRange refreshRateRange = (RefreshRateRange) other;
653             return (min == refreshRateRange.min && max == refreshRateRange.max);
654         }
655 
656         @Override
hashCode()657         public int hashCode() {
658             return Objects.hash(min, max);
659         }
660 
661         @Override
toString()662         public String toString() {
663             return "(" + min + " " + max + ")";
664         }
665     }
666 
667     /**
668      * Describes a limitation on a display's refresh rate. Includes the allowed refresh rate
669      * range as well as information about when it applies, such as high-brightness-mode.
670      */
671     public static final class RefreshRateLimitation {
672         @RefreshRateLimitType public int type;
673 
674         /** The range the that refresh rate should be limited to. */
675         public RefreshRateRange range;
676 
RefreshRateLimitation(@efreshRateLimitType int type, float min, float max)677         public RefreshRateLimitation(@RefreshRateLimitType int type, float min, float max) {
678             this.type = type;
679             range = new RefreshRateRange(min, max);
680         }
681 
682         @Override
toString()683         public String toString() {
684             return "RefreshRateLimitation(" + type + ": " + range + ")";
685         }
686     }
687 }
688