1 /*
2  * Copyright (C) 2022 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 HARDWARE_INTERFACES_CAMERA_PROVIDER_DEFAULT_EXTERNALCAMERAPROVIDER_H_
18 #define HARDWARE_INTERFACES_CAMERA_PROVIDER_DEFAULT_EXTERNALCAMERAPROVIDER_H_
19 
20 #include <ExternalCameraUtils.h>
21 #include <SimpleThread.h>
22 #include <aidl/android/hardware/camera/common/CameraDeviceStatus.h>
23 #include <aidl/android/hardware/camera/common/VendorTagSection.h>
24 #include <aidl/android/hardware/camera/device/ICameraDevice.h>
25 #include <aidl/android/hardware/camera/provider/BnCameraProvider.h>
26 #include <aidl/android/hardware/camera/provider/CameraIdAndStreamCombination.h>
27 #include <aidl/android/hardware/camera/provider/ConcurrentCameraIdCombination.h>
28 #include <aidl/android/hardware/camera/provider/ICameraProviderCallback.h>
29 #include <poll.h>
30 #include <utils/Mutex.h>
31 #include <utils/Thread.h>
32 #include <thread>
33 #include <unordered_map>
34 #include <unordered_set>
35 
36 namespace android {
37 namespace hardware {
38 namespace camera {
39 namespace provider {
40 namespace implementation {
41 
42 using ::aidl::android::hardware::camera::common::CameraDeviceStatus;
43 using ::aidl::android::hardware::camera::common::VendorTagSection;
44 using ::aidl::android::hardware::camera::device::ICameraDevice;
45 using ::aidl::android::hardware::camera::provider::BnCameraProvider;
46 using ::aidl::android::hardware::camera::provider::CameraIdAndStreamCombination;
47 using ::aidl::android::hardware::camera::provider::ConcurrentCameraIdCombination;
48 using ::aidl::android::hardware::camera::provider::ICameraProviderCallback;
49 using ::android::hardware::camera::common::helper::SimpleThread;
50 using ::android::hardware::camera::external::common::ExternalCameraConfig;
51 
52 class ExternalCameraProvider : public BnCameraProvider {
53   public:
54     ExternalCameraProvider();
55     ~ExternalCameraProvider() override;
56     ndk::ScopedAStatus setCallback(
57             const std::shared_ptr<ICameraProviderCallback>& in_callback) override;
58     ndk::ScopedAStatus getVendorTags(std::vector<VendorTagSection>* _aidl_return) override;
59     ndk::ScopedAStatus getCameraIdList(std::vector<std::string>* _aidl_return) override;
60     ndk::ScopedAStatus getCameraDeviceInterface(
61             const std::string& in_cameraDeviceName,
62             std::shared_ptr<ICameraDevice>* _aidl_return) override;
63     ndk::ScopedAStatus notifyDeviceStateChange(int64_t in_deviceState) override;
64     ndk::ScopedAStatus getConcurrentCameraIds(
65             std::vector<ConcurrentCameraIdCombination>* _aidl_return) override;
66     ndk::ScopedAStatus isConcurrentStreamCombinationSupported(
67             const std::vector<CameraIdAndStreamCombination>& in_configs,
68             bool* _aidl_return) override;
69 
70   private:
71     void addExternalCamera(const char* devName);
72     void deviceAdded(const char* devName);
73     void deviceRemoved(const char* devName);
74     void updateAttachedCameras();
75 
76     // A separate thread to monitor '/dev' directory for '/dev/video*' entries
77     // This thread calls back into ExternalCameraProvider when an actionable change is detected.
78     class HotplugThread : public SimpleThread {
79       public:
80         explicit HotplugThread(ExternalCameraProvider* parent);
81         ~HotplugThread() override;
82 
83       protected:
84         bool threadLoop() override;
85 
86       private:
87         // Returns true if thread initialization succeeded, and false if thread initialization
88         // failed.
89         bool initialize();
90 
91         ExternalCameraProvider* mParent = nullptr;
92         const std::unordered_set<std::string> mInternalDevices;
93 
94         bool mIsInitialized = false;
95 
96         int mINotifyFD = -1;
97         int mWd = -1;
98 
99         // struct to wrap mINotifyFD and poll it with timeout
100         struct pollfd mPollFd = {};
101         char mEventBuf[512] = {0};
102     };
103 
104     Mutex mLock;
105     std::shared_ptr<ICameraProviderCallback> mCallback = nullptr;
106     std::unordered_map<std::string, CameraDeviceStatus> mCameraStatusMap;  // camera id -> status
107     const ExternalCameraConfig mCfg;
108     std::shared_ptr<HotplugThread> mHotPlugThread;
109 };
110 
111 }  // namespace implementation
112 }  // namespace provider
113 }  // namespace camera
114 }  // namespace hardware
115 }  // namespace android
116 
117 #endif  // HARDWARE_INTERFACES_CAMERA_PROVIDER_DEFAULT_EXTERNALCAMERAPROVIDER_H_
118