1 /*
2  * Copyright (C) 2015 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 //#define LOG_NDEBUG 0
18 #define LOG_TAG "AWakeLock"
19 #include <utils/Log.h>
20 
21 #include "AWakeLock.h"
22 
23 #include <binder/IPCThreadState.h>
24 #include <binder/IServiceManager.h>
25 #include <media/stagefright/foundation/ADebug.h>
26 #include <powermanager/PowerManager.h>
27 
28 
29 namespace android {
30 
31 const int32_t INVALID_DISPLAY_ID = -1;
32 
AWakeLock()33 AWakeLock::AWakeLock() :
34     mPowerManager(NULL),
35     mWakeLockToken(NULL),
36     mWakeLockCount(0),
37     mDeathRecipient(new PMDeathRecipient(this)){}
38 
~AWakeLock()39 AWakeLock::~AWakeLock() {
40     if (mPowerManager != NULL) {
41         sp<IBinder> binder = IInterface::asBinder(mPowerManager);
42         binder->unlinkToDeath(mDeathRecipient);
43     }
44     clearPowerManager();
45 }
46 
acquire()47 bool AWakeLock::acquire() {
48     if (mWakeLockCount == 0) {
49         CHECK(mWakeLockToken == NULL);
50         if (mPowerManager == NULL) {
51             // use checkService() to avoid blocking if power service is not up yet
52             sp<IBinder> binder =
53                 defaultServiceManager()->checkService(String16("power"));
54             if (binder == NULL) {
55                 ALOGW("could not get the power manager service");
56             } else {
57                 mPowerManager = interface_cast<os::IPowerManager>(binder);
58                 binder->linkToDeath(mDeathRecipient);
59             }
60         }
61         if (mPowerManager != NULL) {
62             sp<IBinder> binder = new BBinder();
63             int64_t token = IPCThreadState::self()->clearCallingIdentity();
64             binder::Status status = mPowerManager->acquireWakeLock(
65                 binder,
66                 /*flags= */ POWERMANAGER_PARTIAL_WAKE_LOCK,
67                 /*tag=*/ String16("AWakeLock"),
68                 /*packageName=*/ String16("media"),
69                 /*ws=*/ {},
70                 /*historyTag=*/ {},
71                 /*displayId=*/ INVALID_DISPLAY_ID,
72                 /*callback=*/NULL);
73             IPCThreadState::self()->restoreCallingIdentity(token);
74             if (status.isOk()) {
75                 mWakeLockToken = binder;
76                 mWakeLockCount++;
77                 ALOGI("AwakeLock acquired");
78                 return true;
79             }
80         }
81     } else {
82         mWakeLockCount++;
83         return true;
84     }
85     return false;
86 }
87 
release(bool force)88 void AWakeLock::release(bool force) {
89     if (mWakeLockCount == 0) {
90         return;
91     }
92     if (force) {
93         // Force wakelock release below by setting reference count to 1.
94         mWakeLockCount = 1;
95     }
96     if (--mWakeLockCount == 0) {
97         CHECK(mWakeLockToken != NULL);
98         if (mPowerManager != NULL) {
99             int64_t token = IPCThreadState::self()->clearCallingIdentity();
100             mPowerManager->releaseWakeLock(mWakeLockToken, 0 /* flags */);
101             IPCThreadState::self()->restoreCallingIdentity(token);
102         }
103         mWakeLockToken.clear();
104         ALOGI("AwakeLock released");
105     }
106 }
107 
clearPowerManager()108 void AWakeLock::clearPowerManager() {
109     release(true);
110     mPowerManager.clear();
111 }
112 
binderDied(const wp<IBinder> & who __unused)113 void AWakeLock::PMDeathRecipient::binderDied(const wp<IBinder>& who __unused) {
114     if (mWakeLock != NULL) {
115         mWakeLock->clearPowerManager();
116     }
117 }
118 
119 }  // namespace android
120