1 /*
2  * Copyright (C) 2013 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 #include "EventControlThread.h"
18 #include "SurfaceFlinger.h"
19 
20 namespace android {
21 
EventControlThread(const sp<SurfaceFlinger> & flinger)22 EventControlThread::EventControlThread(const sp<SurfaceFlinger>& flinger):
23         mFlinger(flinger),
24         mVsyncEnabled(false) {
25 }
26 
setVsyncEnabled(bool enabled)27 void EventControlThread::setVsyncEnabled(bool enabled) {
28     Mutex::Autolock lock(mMutex);
29     mVsyncEnabled = enabled;
30     mCond.signal();
31 }
32 
threadLoop()33 bool EventControlThread::threadLoop() {
34     Mutex::Autolock lock(mMutex);
35 
36     bool vsyncEnabled = mVsyncEnabled;
37 
38 #ifdef USE_HWC2
39     mFlinger->setVsyncEnabled(HWC_DISPLAY_PRIMARY, mVsyncEnabled);
40 #else
41     mFlinger->eventControl(HWC_DISPLAY_PRIMARY, SurfaceFlinger::EVENT_VSYNC,
42             mVsyncEnabled);
43 #endif
44 
45     while (true) {
46         status_t err = mCond.wait(mMutex);
47         if (err != NO_ERROR) {
48             ALOGE("error waiting for new events: %s (%d)",
49                 strerror(-err), err);
50             return false;
51         }
52 
53         if (vsyncEnabled != mVsyncEnabled) {
54 #ifdef USE_HWC2
55             mFlinger->setVsyncEnabled(HWC_DISPLAY_PRIMARY, mVsyncEnabled);
56 #else
57             mFlinger->eventControl(HWC_DISPLAY_PRIMARY,
58                     SurfaceFlinger::EVENT_VSYNC, mVsyncEnabled);
59 #endif
60             vsyncEnabled = mVsyncEnabled;
61         }
62     }
63 
64     return false;
65 }
66 
67 } // namespace android
68