EventThread.h revision 22ffb117b0c2a906bd04aef9738a52223cdd1dce 
1/*
2 * Copyright (C) 2011 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#ifndef ANDROID_SURFACE_FLINGER_EVENT_THREAD_H
18#define ANDROID_SURFACE_FLINGER_EVENT_THREAD_H
19
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <gui/DisplayEventReceiver.h>
24#include <gui/IDisplayEventConnection.h>
25
26#include <utils/Errors.h>
27#include <utils/threads.h>
28#include <utils/SortedVector.h>
29
30#include "DisplayHardware/DisplayHardware.h"
31
32// ---------------------------------------------------------------------------
33
34namespace android {
35
36// ---------------------------------------------------------------------------
37
38class SurfaceFlinger;
39
40// ---------------------------------------------------------------------------
41
42class EventThread : public Thread, public DisplayHardware::VSyncHandler {
43    class Connection : public BnDisplayEventConnection {
44    public:
45        Connection(const sp<EventThread>& eventThread);
46        status_t postEvent(const DisplayEventReceiver::Event& event);
47
48        // count >= 1 : continuous event. count is the vsync rate
49        // count == 0 : one-shot event that has not fired
50        // count ==-1 : one-shot event that fired this round / disabled
51        // count ==-2 : one-shot event that fired the round before
52        int32_t count;
53
54    private:
55        virtual ~Connection();
56        virtual void onFirstRef();
57        virtual sp<BitTube> getDataChannel() const;
58        virtual void setVsyncRate(uint32_t count);
59        virtual void requestNextVsync();    // asynchronous
60        sp<EventThread> const mEventThread;
61        sp<BitTube> const mChannel;
62    };
63
64public:
65
66    EventThread(const sp<SurfaceFlinger>& flinger);
67
68    sp<Connection> createEventConnection() const;
69    status_t registerDisplayEventConnection(const sp<Connection>& connection);
70    status_t unregisterDisplayEventConnection(const wp<Connection>& connection);
71
72    void setVsyncRate(uint32_t count, const sp<Connection>& connection);
73    void requestNextVsync(const sp<Connection>& connection);
74
75    // called before the screen is turned off from main thread
76    void onScreenReleased();
77
78    // called after the screen is turned on from main thread
79    void onScreenAcquired();
80
81    void dump(String8& result, char* buffer, size_t SIZE) const;
82
83private:
84    virtual bool        threadLoop();
85    virtual status_t    readyToRun();
86    virtual void        onFirstRef();
87    virtual void        onVSyncReceived(int, nsecs_t timestamp);
88
89    void removeDisplayEventConnection(const wp<Connection>& connection);
90    void enableVSyncLocked();
91    void disableVSyncLocked();
92
93    // constants
94    sp<SurfaceFlinger> mFlinger;
95    DisplayHardware& mHw;
96
97    mutable Mutex mLock;
98    mutable Condition mCondition;
99
100    // protected by mLock
101    SortedVector< wp<Connection> > mDisplayEventConnections;
102    nsecs_t mLastVSyncTimestamp;
103    nsecs_t mVSyncTimestamp;
104    bool mUseSoftwareVSync;
105
106    // main thread only
107    size_t mDeliveredEvents;
108
109    // for debugging
110    bool mDebugVsyncEnabled;
111};
112
113// ---------------------------------------------------------------------------
114
115}; // namespace android
116
117// ---------------------------------------------------------------------------
118
119#endif /* ANDROID_SURFACE_FLINGER_EVENT_THREAD_H */
120