Android15 EVS HAL中使用Camera HAL Provider接口

叶羽西2026-01-13 13:29

EVS HAL和Camera HAL是Android系统中访问相机设备节点的两条路径，理论上是独立的两个HAL层。现在想做一个验证：EVS HAL初始化阶段通过Camera HAL Provider接口设备节点是否可行（理论上是可行的），查询操作的耗时怎样。

跨HAL访问Camera HAL Provider接口如下：

1.添加ICameraProvider的引用

cpp 复制代码

//packages/services/Car/cpp/evs/sampleDriver/aidl/src/EvsEnumerator.h
//添加ICameraProvider.h引用
#include <aidl/android/hardware/camera/provider/ICameraProvider.h>

//packages/services/Car/cpp/evs/sampleDriver/aidl/src/EvsEnumerator.cpp
//添加ICameraProvider namespace声明和接口使用
using ::aidl::android::hardware::camera::provider::ICameraProvider;

void EvsEnumerator::enumerateCameras() {
    if (!sConfigManager) {
        return;
    }

    //如下是查询CameraProvider
    LOG(INFO) << "#####START ";
    {
        std::vector<std::string> cameraList;
        const std::string serviceDescriptor = 
            std::string(ICameraProvider::descriptor) + "/internal/0";
        ndk::SpAIBinder cameraProviderBinder = 
            ndk::SpAIBinder(AServiceManager_waitForService(serviceDescriptor.c_str()));
        if (cameraProviderBinder.get() == nullptr) {
            LOG(ERROR) << "Get camera service failed.";
            return;
        }
        std::shared_ptr<ICameraProvider> cameraProvider = 
            ICameraProvider::fromBinder(cameraProviderBinder);
        if (cameraProvider.get() == nullptr) {
            LOG(ERROR) << "Get camera service failed.";
            return;
        }

        ScopedAStatus ret = cameraProvider->getCameraIdList(&cameraList);
        if (ret.get() == nullptr) {
            LOG(ERROR) << "Get camera list failed.";
        } else {
            LOG(INFO) << "The platform has " << cameraList.size() << " cameras";
        }
    }
    LOG(INFO) << "#####STOP ";
    ...
}

2.添加对ICameraProvider的依赖关系

cpp 复制代码

//packages/services/Car/cpp/evs/sampleDriver/aidl/Android.bp
cc_binary {
    name: "android.hardware.automotive.evs-default",
    defaults: ["android.hardware.graphics.common-ndk_static"],
    ...
    static_libs: [
        "android.frameworks.automotive.display-V2-ndk",
        "android.hardware.automotive.evs-V2-ndk",
        "android.hardware.common-V2-ndk",
        "libaidlcommonsupport",
        "libcutils",
        "android.hardware.camera.provider-V3-ndk",
    ]
    ...
}