文章目录
- [1 camera open总结](#1 camera open总结)
- [2 Camera Open 代码流程分析](#2 Camera Open 代码流程分析)
-
- [2.1 Java 层 Camera Class 使用介绍](#2.1 Java 层 Camera Class 使用介绍)
- [2.2 Frameworks 层 Camera.java 分析](#2.2 Frameworks 层 Camera.java 分析)
-
- [2.2.1 \[JNI] CameraService初始化 native\_setup( ) ---> android\_hardware\_Camera\_native\_setup( )](#2.2.1 [JNI] CameraService初始化 native_setup( ) —> android_hardware_Camera_native_setup( ))
- [2.2.2 \[AIDL] interface ICameraService](#2.2.2 [AIDL] interface ICameraService)
- [2.2.3 \[Native] CameraService.cpp](#2.2.3 [Native] CameraService.cpp)
-
- [2.2.3.1 \[CameraService] 创建 Camera 客户端 makeClient( )](#2.2.3.1 [CameraService] 创建 Camera 客户端 makeClient( ))
- [2.2.3.2 \[Camera2Client] Camera2Client初始化 client->initialize(mModule))](#2.2.3.2 [Camera2Client] Camera2Client初始化 client->initialize(mModule)))
-
- [2.2.3.2.1 \[Camera3Device] Camera device 初始化 mDevice->initialize(module)](#2.2.3.2.1 [Camera3Device] Camera device 初始化 mDevice->initialize(module))
- [2.2.3.2.2 \[CameraProviderManager] manager->openSession](#2.2.3.2.2 [CameraProviderManager] manager->openSession)
- [2.2.3.3 \[CameraDevice] CameraDevice::open](#2.2.3.3 [CameraDevice] CameraDevice::open)
- [2.2.3.4 \[CameraModule] CameraModule::open](#2.2.3.4 [CameraModule] CameraModule::open)
-
- [2.2.3.4.1 \[hardware] camera\_module\_t](#2.2.3.4.1 [hardware] camera_module_t)
- [2.2.3.5 \[Hardware] 打开设备 QCamera2Factory::cameraDeviceOpen()](#2.2.3.5 [Hardware] 打开设备 QCamera2Factory::cameraDeviceOpen())
-
- [2.2.3.5.1 camera\_open((uint8\_t)mCameraId, \&mCameraHandle)](#2.2.3.5.1 camera_open((uint8_t)mCameraId, &mCameraHandle))
- [2.2.3.5.2 Camera 操作节构体 cam\_obj->vtbl.ops](#2.2.3.5.2 Camera 操作节构体 cam_obj->vtbl.ops)
- [2.2.3.5.3 \[Hardware] 初始化Framewroks层的Callback 函数 QCamera3HardwareInterface::initialize( )](#2.2.3.5.3 [Hardware] 初始化Framewroks层的Callback 函数 QCamera3HardwareInterface::initialize( ))
- [2.2.4 EventHandler( )](#2.2.4 EventHandler( ))
- [2.3 内核层msm\_open](#2.3 内核层msm_open)
- [3 OpenSession 流程分析](#3 OpenSession 流程分析)
-
- [3.1 mm-camera2框架](#3.1 mm-camera2框架)
- [3.2 media controller线程](#3.2 media controller线程)
-
- [3.2.1 mm\_camera\_module\_open\_session](#3.2.1 mm_camera_module_open_session)
- [3.2.2 mct\_shimlayer\_process\_module\_init](#3.2.2 mct_shimlayer_process_module_init)
- [3.2.3 mct\_shimlayer\_start\_session](#3.2.3 mct_shimlayer_start_session)
- [3.2.4 mct\_controller\_new](#3.2.4 mct_controller_new)
-
- [3.2.4.1 mct\_pipeline\_new](#3.2.4.1 mct_pipeline_new)
- [3.2.4.2 mct\_pipeline\_start\_session](#3.2.4.2 mct_pipeline_start_session)
- [3.2.4.3 mct\_pipeline\_modules\_start](#3.2.4.3 mct_pipeline_modules_start)
- [3.2.4.4 mct\_pipeline\_start\_session\_thread](#3.2.4.4 mct_pipeline_start_session_thread)
- [3.3 else](#3.3 else)
- [3.3 else](#3.3 else)
1 camera open总结
整个Camera Open 过程总结如下：
Java APP 层
调用 Frameworks 层 Camera.java 中的 open() 方法，
在open camera 后，才开始调用对应的 getParameters()，setParameters()， startPreview() 等 函数，这些后续分析
Frameworks 层 Camera.java 中的 open()(1) 在Camera open() 函数中，如果没有指定open 对应的camera id，则默认打开后摄
(2) 根据传入的 camera id 进行初始化
(3) 注册 EventHandler 循环监听Camera 事件
(4) 调用 native_setup() JNI 函数，并下发 camera id 、当前包名、hal层版本号
JNI 层 android_hardware_Camera_native_setup(1) 调用 Camera::connect() 函数，connect 为 AIDL 方法，通过binder 调用到服务端CameraService.cpp中的 CameraService::connect() 方法中
(2) 获取 Camera Class，建立专门负责与java Camera对象通信的对象
(3) 如果没有设置屏幕显示方向，则默认为0，如果不为0，调用sendCommand 下发屏幕显示方向
C++ Native 层 CameraService.cpp 中(1) CameraService.cpp 是camera 初始化中讲过了，在开机时会注册好对应的 cameraservice 服务
(2) 前面AIDL中，调用到 CameraService.cpp中的 CameraService::connect() 方法 在该方法中，
(3) 首先检查是否存在 client ，如果存在的话直接返回
(4) 关闭所有的 flashlight 对象
(5) 调用makeClient() 创建 Camera Client 对象。 client是通过 Camera2ClientBase() 进行创建的，同时创建Camera3Device 对象
(6) 调用client->initialize对前面创建好的 Camera client 进行初始化
(7) 初始化前先对device 进行初始化 ，在Camera3Device->initialize()中打开对应的 Camera 节点/dev/videox，进行初始化，获取到 Camera 的操作方法
(8) 初始化 Camera 默认参数
(9) 接着对创建 Camera 运行时的六大线程，
处理preview和录像 stream的线程、处理3A和人脸识别的线程、拍照流程状态机线程、处理拍照 jpeg stream 线程、处理零延时zsl stream使用的线程、处理callback的线程
2 Camera Open 代码流程分析
2.1 Java 层 Camera Class 使用介绍
先看下谷歌官方对 Camera Class 的介绍：
The Camera class is used to set image capture settings, start/stop preview,
snap pictures, and retrieve frames for encoding for video.
This Class is a client for the Camera service, which manages the actual camera hardware.
2.2 Frameworks 层 Camera.java 分析
调用 Frameworks 层 Camera.java 中的 open() 方法，
在open camera 后，才开始调用对应的 getParameters()，setParameters()， startPreview() 等 函数，这些后续分析
Java 层中调用的 Camera Class 源码位于 frameworks/base/core/java/android/hardware/Camera.java，
整个过程，主要工作如下：
(1) 在Camera open() 函数中，如果没有指定open 对应的camera id，则默认打开后摄
(2) 根据传入的 camera id 进行初始化
(3) 注册 EventHandler 循环监听Camera 事件
(4) 调用 native_setup() JNI 函数，并下发 camera id 、当前包名、hal层版本号 @ frameworks/base/core/java/android/hardware/Camera.java
java
public class Camera {
private static final String TAG = "Camera";
private CameraDataCallback mCameraDataCallback;
private CameraMetaDataCallback mCameraMetaDataCallback;
public static final int CAMERA_HAL_API_VERSION_1_0 = 0x100;
public static class CameraInfo {
public static final int CAMERA_FACING_BACK = 0;
public static final int CAMERA_FACING_FRONT = 1;
public static final int CAMERA_SUPPORT_MODE_ZSL = 2;
public static final int CAMERA_SUPPORT_MODE_NONZSL = 3;
public int facing;
public int orientation;
public boolean canDisableShutterSound;
};
// 1. 找开指定 id 的Camera
public static Camera open(int cameraId) {
return new Camera(cameraId);
}
// 2. 在Camera open() 函数中，如果没有指定open 对应的camera id，则默认打开后摄
public static Camera open() {
int numberOfCameras = getNumberOfCameras();
CameraInfo cameraInfo = new CameraInfo();
for (int i = 0; i < numberOfCameras; i++) {
getCameraInfo(i, cameraInfo);
if (cameraInfo.facing == CameraInfo.CAMERA_FACING_BACK) {
return new Camera(i);
}
}
return null;
}
// 3. 调用 cameraInitNormal() 初始对应 id 的Camera
/** used by Camera#open, Camera#open(int) */
Camera(int cameraId) {
int err = cameraInitNormal(cameraId);
}
private int cameraInitNormal(int cameraId) {
return cameraInitVersion(cameraId, CAMERA_HAL_API_VERSION_NORMAL_CONNECT); // -2
}
private int cameraInitVersion(int cameraId, int halVersion) {
mShutterCallback = null;
mRawImageCallback = null;
mJpegCallback = null;
mPreviewCallback = null;
mPostviewCallback = null;
mUsingPreviewAllocation = false;
mZoomListener = null;
/* ### QC ADD-ONS: START */
mCameraDataCallback = null;
mCameraMetaDataCallback = null;
/* ### QC ADD-ONS: END */
// 1. 注册 EventHandler 循环监听Camera 事件
Looper looper;
if ((looper = Looper.myLooper()) != null) {
mEventHandler = new EventHandler(this, looper);
} else if ((looper = Looper.getMainLooper()) != null) {
mEventHandler = new EventHandler(this, looper);
} else {
mEventHandler = null;
}
// 2. 获取当前包名
String packageName = ActivityThread.currentOpPackageName();
// 3. 如果定义了 prop 属性 "camera.hal1.packagelist" ， 则强制使用 HAL1
//Force HAL1 if the package name falls in this bucket
String packageList = SystemProperties.get("camera.hal1.packagelist", "");
if (packageList.length() > 0) {
TextUtils.StringSplitter splitter = new TextUtils.SimpleStringSplitter(',');
splitter.setString(packageList);
for (String str : splitter) {
if (packageName.equals(str)) {
halVersion = CAMERA_HAL_API_VERSION_1_0;
break;
}
}
}
// 4. 调用 native_setup() JNI 函数，并下发 camera id 、当前包名、hal层版本号
return native_setup(new WeakReference<Camera>(this), cameraId, halVersion, packageName);
}2.2.1 [JNI] CameraService初始化 native_setup( ) ---> android_hardware_Camera_native_setup( )
java 中通过JNI 调用 native 方法，Camera JNI 代码位于 @ frameworks/base/core/jni/android_hardware_Camera.cpp
cpp
//cameraId = 0
//halVersion = -2
native_setup(new WeakReference<Camera>(this), cameraId, halVersion, packageName);
static const JNINativeMethod camMethods[] = {
{ "_getNumberOfCameras", "()I", (void *)android_hardware_Camera_getNumberOfCameras },
{ "_getCameraInfo", "(ILandroid/hardware/Camera$CameraInfo;)V", (void*)android_hardware_Camera_getCameraInfo },
{ "native_setup", "(Ljava/lang/Object;IILjava/lang/String;)I", (void*)android_hardware_Camera_native_setup },
{ "native_release", "()V", (void*)android_hardware_Camera_release },
{ "setPreviewSurface", "(Landroid/view/Surface;)V", (void *)android_hardware_Camera_setPreviewSurface },
{ "setPreviewTexture", "(Landroid/graphics/SurfaceTexture;)V", (void *)android_hardware_Camera_setPreviewTexture },
{ "setPreviewCallbackSurface", "(Landroid/view/Surface;)V", (void *)android_hardware_Camera_setPreviewCallbackSurface },
{ "startPreview", "()V", (void *)android_hardware_Camera_startPreview },
{ "_stopPreview", "()V", (void *)android_hardware_Camera_stopPreview },
{ "previewEnabled", "()Z", (void *)android_hardware_Camera_previewEnabled },
{ "setHasPreviewCallback","(ZZ)V", (void *)android_hardware_Camera_setHasPreviewCallback },
{ "_addCallbackBuffer", "([BI)V", (void *)android_hardware_Camera_addCallbackBuffer },
{ "native_autoFocus", "()V", (void *)android_hardware_Camera_autoFocus },
{ "native_cancelAutoFocus","()V", (void *)android_hardware_Camera_cancelAutoFocus },
{ "native_takePicture", "(I)V", (void *)android_hardware_Camera_takePicture },
{ "native_setHistogramMode","(Z)V", (void *)android_hardware_Camera_setHistogramMode },
{ "native_setMetadataCb", "(Z)V", (void *)android_hardware_Camera_setMetadataCb },
{ "native_sendHistogramData","()V", (void *)android_hardware_Camera_sendHistogramData },
{ "native_setLongshot", "(Z)V", (void *)android_hardware_Camera_setLongshot },
{ "native_setParameters", "(Ljava/lang/String;)V", (void *)android_hardware_Camera_setParameters },
{ "native_getParameters", "()Ljava/lang/String;", (void *)android_hardware_Camera_getParameters },
{ "reconnect", "()V", (void*)android_hardware_Camera_reconnect },
{ "lock", "()V", (void*)android_hardware_Camera_lock },
{ "unlock", "()V", (void*)android_hardware_Camera_unlock },
{ "startSmoothZoom", "(I)V", (void *)android_hardware_Camera_startSmoothZoom },
{ "stopSmoothZoom", "()V", (void *)android_hardware_Camera_stopSmoothZoom },
{ "setDisplayOrientation","(I)V", (void *)android_hardware_Camera_setDisplayOrientation },
{ "_enableShutterSound", "(Z)Z", (void *)android_hardware_Camera_enableShutterSound },
{ "_startFaceDetection", "(I)V", (void *)android_hardware_Camera_startFaceDetection },
{ "_stopFaceDetection", "()V", (void *)android_hardware_Camera_stopFaceDetection},
{ "enableFocusMoveCallback","(I)V", (void *)android_hardware_Camera_enableFocusMoveCallback},
};在
cpp
// connect to camera service
static jint android_hardware_Camera_native_setup(JNIEnv *env, jobject thiz, jobject weak_this, jint cameraId, jint halVersion, jstring clientPackageName)
{
// Convert jstring to String16
const char16_t *rawClientName = reinterpret_cast<const char16_t*>(env->GetStringChars(clientPackageName, NULL));
jsize rawClientNameLen = env->GetStringLength(clientPackageName);
String16 clientName(rawClientName, rawClientNameLen);
env->ReleaseStringChars(clientPackageName, reinterpret_cast<const jchar*>(rawClientName));
sp<Camera> camera;
if (halVersion == CAMERA_HAL_API_VERSION_NORMAL_CONNECT) { // -2
// Default path: hal version is don't care, do normal camera connect.
// 调用 Camera::connect() 函数，connect 为 AIDL 方法，
// 通过binder 调用到服务端CameraService.cpp中的 CameraService::connect() 方法中
camera = Camera::connect(cameraId, clientName, Camera::USE_CALLING_UID, Camera::USE_CALLING_PID);
======================>
+ // frameworks/av/camera/Camera.cpp
+ return CameraBaseT::connect(cameraId, clientPackageName, clientUid, clientPid);
+ ========>
+ // frameworks/av/camera/CameraBase.cpp
+ sp<TCam> CameraBase<TCam, TCamTraits>::connect(int cameraId, const String16& clientPackageName, int clientUid, int clientPid)
+ {
+ - sp<TCam> c = new TCam(cameraId);
+ - sp<TCamCallbacks> cl = c;
+ const sp<::android::hardware::ICameraService> cs = getCameraService();
+ TCamConnectService fnConnectService = TCamTraits::fnConnectService;
+ ret = (cs.get()->*fnConnectService)(cl, cameraId, clientPackageName, clientUid, clientPid, /*out*/ &c->mCamera);
+ --------->
+ CameraTraits<Camera>::TCamConnectService CameraTraits<Camera>::fnConnectService =
+ &::android::hardware::ICameraService::connect;
+
+ IInterface::asBinder(c->mCamera)->linkToDeath(c);
+ return c;
+ }
+ <========
<======================
} else {
jint status = Camera::connectLegacy(cameraId, halVersion, clientName, Camera::USE_CALLING_UID, camera);
if (status != NO_ERROR) {
return status;
}
}
// make sure camera hardware is alive
if (camera->getStatus() != NO_ERROR) {
return NO_INIT;
}
// 获取 Camera Class
jclass clazz = env->GetObjectClass(thiz);
if (clazz == NULL) {
// This should never happen
jniThrowRuntimeException(env, "Can't find android/hardware/Camera");
return INVALID_OPERATION;
}
// We use a weak reference so the Camera object can be garbage collected.
// The reference is only used as a proxy for callbacks.
sp<JNICameraContext> context = new JNICameraContext(env, weak_this, clazz, camera);
context->incStrong((void*)android_hardware_Camera_native_setup);
camera->setListener(context); // 专门负责与java Camera对象通信的对象
// save context in opaque field
env->SetLongField(thiz, fields.context, (jlong)context.get());
// Update default display orientation in case the sensor is reverse-landscape
CameraInfo cameraInfo;
status_t rc = Camera::getCameraInfo(cameraId, &cameraInfo);
int defaultOrientation = 0;
switch (cameraInfo.orientation) {
case 0: break;
case 90:
if (cameraInfo.facing == CAMERA_FACING_FRONT) {
defaultOrientation = 180;
}
break;
case 180:
defaultOrientation = 180;
break;
case 270:
if (cameraInfo.facing != CAMERA_FACING_FRONT) {
defaultOrientation = 180;
}
break;
default:
ALOGE("Unexpected camera orientation %d!", cameraInfo.orientation);
break;
}
// 如果没有设置屏幕显示方向，则默认为0，如果不为0，调用sendCommand 下发屏幕显示方向
if (defaultOrientation != 0) {
ALOGV("Setting default display orientation to %d", defaultOrientation);
rc = camera->sendCommand(CAMERA_CMD_SET_DISPLAY_ORIENTATION,defaultOrientation, 0);
}
return NO_ERROR;
}2.2.2 [AIDL] interface ICameraService
在前面代码中， 经过如下一系列调用，最终走到了 AIDL 层。
native_setup() ---> android_hardware_Camera_native_setup() ---> CameraBaseT::connect ---> sp<TCam> CameraBase<TCam, TCamTraits>::connect ---> ret = (cs.get()->*fnConnectService) ---> ::android::hardware::ICameraService::connect()
fnConnectService 定义如下：
CameraTraits<Camera>::TCamConnectService CameraTraits<Camera>::fnConnectService = &::android::hardware::ICameraService::connect;
@frameworks/av/camera/aidl/android/hardware/ICameraService.aidl
cc
/**
* Binder interface for the native camera service running in mediaserver.
* @hide
*/
interface ICameraService
{
/** Open a camera device through the old camera API */
ICamera connect(ICameraClient client, int cameraId, String opPackageName, int clientUid, int clientPid);
/** Open a camera device through the new camera API Only supported for device HAL versions >= 3.2 */
ICameraDeviceUser connectDevice(ICameraDeviceCallbacks callbacks, int cameraId,String opPackageName,int clientUid);
}AIDL 中，我们走的是老方法， ICamera connect().
AIDL------Android Interface Definition Language,是一种接口定义语言，用于生成可以在Android设备上两个进程间进行通信的代码。
Android Java Service Framework提供的大多数系统服务都是使用AIDL语言生成的。使用AIDL语言，可以自动生成服务接口、服务代理、服务Stub代码。
2.2.3 [Native] CameraService.cpp
通过 AIDL 的 Binder 通信，跳转到 CameraService.cpp 中。CameraService.cpp 是在开机时会注册好对应的 cameraservice 服务。
此时通过Binder通信，调用CameraService 服务中的 connect 方法： @frameworks/av/services/camera/libcameraservice/CameraService.cpp
cc
Status CameraService::connect(
const sp<ICameraClient>& cameraClient,
int cameraId,
const String16& clientPackageName,
int clientUid,
int clientPid,
/*out*/
sp<ICamera>* device) {
String8 id = String8::format("%d", cameraId);
sp<Client> client = nullptr;
ret = connectHelper<ICameraClient,Client>(cameraClient, id,
CAMERA_HAL_API_VERSION_UNSPECIFIED, clientPackageName, clientUid, clientPid, API_1,
/*legacyMode*/ false, /*shimUpdateOnly*/ false,
/*out*/client);
*device = client;
return ret;
}进入 connectHelper 函数看下：
1.检查 Client 的权限
2.如果已存在 client 则直接返回
3.在打开Camera 前，所有Flashlight 都应该被关闭
4.调用makeClient() 创建 Camera Client 对象。 client是通过 Camera2ClientBase() 进行创建的，同时创建Camera3Device 对象
5.调用client->initialize对前面创建好的 Camera client 进行初始化
cpp
template<class CALLBACK, class CLIENT>
binder::Status CameraService::connectHelper(const sp<CALLBACK>& cameraCb, const String8& cameraId,
int halVersion, const String16& clientPackageName, int clientUid, int clientPid,
apiLevel effectiveApiLevel, bool legacyMode, bool shimUpdateOnly,
/*out*/sp<CLIENT>& device) {
binder::Status ret = binder::Status::ok();
String8 clientName8(clientPackageName);
int originalClientPid = 0;
//这里可以打印 camera的包名 cameraId 以及camera API version
ALOGI("CameraService::connect call (PID %d \"%s\", camera ID %s) for HAL version %s and "
"Camera API version %d", clientPid, clientName8.string(), cameraId.string(),
(halVersion == -1) ? "default" : std::to_string(halVersion).c_str(), static_cast<int>(effectiveApiLevel));
sp<CLIENT> client = nullptr;
{
// 1. 检查 Client 的权限
// Enforce client permissions and do basic sanity checks
if(!(ret = validateConnectLocked(cameraId, clientName8, /*inout*/clientUid, /*inout*/clientPid, /*out*/originalClientPid)).isOk()) {
return ret;
}
sp<BasicClient> clientTmp = nullptr;
std::shared_ptr<resource_policy::ClientDescriptor<String8, sp<BasicClient>>> partial;
err = handleEvictionsLocked(cameraId, originalClientPid, effectiveApiLevel,
IInterface::asBinder(cameraCb), clientName8, /*out*/&clientTmp, /*out*/&partial));
// 2. 如果已存在 client 则直接返回
if (clientTmp.get() != nullptr) {
// Handle special case for API1 MediaRecorder where the existing client is returned
device = static_cast<CLIENT*>(clientTmp.get());
return ret;
}
// 3. 在打开Camera 前，所有Flashlight 都应该被关闭
// give flashlight a chance to close devices if necessary.
mFlashlight->prepareDeviceOpen(cameraId);
// TODO: Update getDeviceVersion + HAL interface to use strings for Camera IDs
int id = cameraIdToInt(cameraId);
int facing = -1;
int deviceVersion = getDeviceVersion(id, /*out*/&facing);
sp<BasicClient> tmp = nullptr;
// 4. 调用makeClient() 创建 Camera Client 对象。 client是通过 Camera2ClientBase() 进行创建的，同时创建Camera3Device 对象
if(!(ret = makeClient(this, cameraCb, clientPackageName, id, facing, clientPid,
clientUid, getpid(), legacyMode, halVersion, deviceVersion, effectiveApiLevel,
/*out*/&tmp)).isOk()) {
return ret;
}
client = static_cast<CLIENT*>(tmp.get()); // Camera2Client
LOG_ALWAYS_FATAL_IF(client.get() == nullptr, "%s: CameraService in invalid state",
__FUNCTION__);
// 5. 调用client->initialize对前面创建好的 Camera client 进行初始化
if ((err = client->initialize(mModule)) != OK) {
ALOGE("%s: Could not initialize client from HAL module.", __FUNCTION__);
// Errors could be from the HAL module open call or from AppOpsManager
switch(err) {
case BAD_VALUE:
return STATUS_ERROR_FMT(ERROR_ILLEGAL_ARGUMENT,
"Illegal argument to HAL module for camera \"%s\"", cameraId.string());
case -EBUSY:
return STATUS_ERROR_FMT(ERROR_CAMERA_IN_USE,
"Camera \"%s\" is already open", cameraId.string());
case -EUSERS:
return STATUS_ERROR_FMT(ERROR_MAX_CAMERAS_IN_USE,
"Too many cameras already open, cannot open camera \"%s\"",
cameraId.string());
case PERMISSION_DENIED:
return STATUS_ERROR_FMT(ERROR_PERMISSION_DENIED,
"No permission to open camera \"%s\"", cameraId.string());
case -EACCES:
return STATUS_ERROR_FMT(ERROR_DISABLED,
"Camera \"%s\" disabled by policy", cameraId.string());
case -ENODEV:
default:
return STATUS_ERROR_FMT(ERROR_INVALID_OPERATION,
"Failed to initialize camera \"%s\": %s (%d)", cameraId.string(),
strerror(-err), err);
}
}
// Update shim paremeters for legacy clients
if (effectiveApiLevel == API_1) {
// Assume we have always received a Client subclass for API1
sp<Client> shimClient = reinterpret_cast<Client*>(client.get());
String8 rawParams = shimClient->getParameters();
CameraParameters params(rawParams);
auto cameraState = getCameraState(cameraId);
if (cameraState != nullptr) {
cameraState->setShimParams(params);
} else {
ALOGE("%s: Cannot update shim parameters for camera %s, no such device exists.",
__FUNCTION__, cameraId.string());
}
}
if (shimUpdateOnly) {
// If only updating legacy shim parameters, immediately disconnect client
mServiceLock.unlock();
client->disconnect();
mServiceLock.lock();
} else {
// Otherwise, add client to active clients list
finishConnectLocked(client, partial);
}
} // lock is destroyed, allow further connect calls
// Important: release the mutex here so the client can call back into the service from its
// destructor (can be at the end of the call)
device = client;
return ret;
}2.2.3.1 [CameraService] 创建 Camera 客户端 makeClient( )
接着调用
makeClient(this, cameraCb, clientPackageName, id, facing, clientPid, clientUid, getpid(), legacyMode, halVersion, deviceVersion, effectiveApiLevel, /out /&tmp))
根据 deviceVersion选择Camera1 or Camera2 API route @ frameworks/av/services/camera/libcameraservice/CameraService.cpp
cpp
Status CameraService::makeClient(const sp<CameraService>& cameraService,
const sp<IInterface>& cameraCb, const String16& packageName, int cameraId,
int facing, int clientPid, uid_t clientUid, int servicePid, bool legacyMode,
int halVersion, int deviceVersion, apiLevel effectiveApiLevel,
/*out*/sp<BasicClient>* client) {
if (halVersion < 0 || halVersion == deviceVersion) {
// Default path: HAL version is unspecified by caller, create CameraClient
// based on device version reported by the HAL.
switch(deviceVersion) {
case CAMERA_DEVICE_API_VERSION_1_0:
if (effectiveApiLevel == API_1) { // Camera1 API route
sp<ICameraClient> tmp = static_cast<ICameraClient*>(cameraCb.get());
*client = new CameraClient(cameraService, tmp, packageName, cameraId, facing,
clientPid, clientUid, getpid(), legacyMode);
} else { // Camera2 API route
ALOGW("Camera using old HAL version: %d", deviceVersion);
return STATUS_ERROR_FMT(ERROR_DEPRECATED_HAL,
"Camera device \"%d\" HAL version %d does not support camera2 API",
cameraId, deviceVersion);
}
break;
case CAMERA_DEVICE_API_VERSION_3_0:
case CAMERA_DEVICE_API_VERSION_3_1:
case CAMERA_DEVICE_API_VERSION_3_2:
case CAMERA_DEVICE_API_VERSION_3_3:
case CAMERA_DEVICE_API_VERSION_3_4:
if (effectiveApiLevel == API_1) {
// Camera1 API route
sp<ICameraClient> tmp = static_cast<ICameraClient*>(cameraCb.get());
*client = new Camera2Client(cameraService, tmp, packageName, cameraId, facing,
clientPid, clientUid, servicePid, legacyMode);
} else {
// Camera2 API route
sp<hardware::camera2::ICameraDeviceCallbacks> tmp =
static_cast<hardware::camera2::ICameraDeviceCallbacks*>(cameraCb.get());
*client = new CameraDeviceClient(cameraService, tmp, packageName, cameraId,
facing, clientPid, clientUid, servicePid);
}
break;
}
} else {
// A particular HAL version is requested by caller. Create CameraClient
// based on the requested HAL version.
if (deviceVersion > CAMERA_DEVICE_API_VERSION_1_0 &&
halVersion == CAMERA_DEVICE_API_VERSION_1_0) {
// Only support higher HAL version device opened as HAL1.0 device.
sp<ICameraClient> tmp = static_cast<ICameraClient*>(cameraCb.get());
*client = new CameraClient(cameraService, tmp, packageName, cameraId, facing,
clientPid, clientUid, servicePid, legacyMode);
} else {
// Other combinations (e.g. HAL3.x open as HAL2.x) are not supported yet.
ALOGE("Invalid camera HAL version %x: HAL %x device can only be"
" opened as HAL %x device", halVersion, deviceVersion,
CAMERA_DEVICE_API_VERSION_1_0);
return STATUS_ERROR_FMT(ERROR_ILLEGAL_ARGUMENT,
"Camera device \"%d\" (HAL version %d) cannot be opened as HAL version %d",
cameraId, deviceVersion, halVersion);
}
}
return Status::ok();
}接着调用 *client = new Camera2Client(cameraService, tmp, packageName, cameraId, facing, clientPid, clientUid, servicePid, legacyMode);
client是通过 Camera2ClientBase() 进行创建的 @ frameworks/av/services/camera/libcameraservice/api1/Camera2Client.cpp
cpp
Camera2Client::Camera2Client(const sp<CameraService>& cameraService,
const sp<hardware::ICameraClient>& cameraClient,
const String16& clientPackageName,
int cameraId,
int cameraFacing,
int clientPid,
uid_t clientUid,
int servicePid,
bool legacyMode):
Camera2ClientBase(cameraService, cameraClient, clientPackageName,
cameraId, cameraFacing, clientPid, clientUid, servicePid),
mParameters(cameraId, cameraFacing)
{
ATRACE_CALL();
SharedParameters::Lock l(mParameters);
l.mParameters.state = Parameters::DISCONNECTED;
mLegacyMode = legacyMode;
}创建Camera3Device 对象
c
// Interface used by CameraService
template <typename TClientBase>
Camera2ClientBase<TClientBase>::Camera2ClientBase(
const sp<CameraService>& cameraService,
const sp<TCamCallbacks>& remoteCallback,
const String16& clientPackageName,
int cameraId,
int cameraFacing,
int clientPid,
uid_t clientUid,
int servicePid):
TClientBase(cameraService, remoteCallback, clientPackageName,cameraId, cameraFacing, clientPid, clientUid, servicePid),
mSharedCameraCallbacks(remoteCallback),
mDeviceVersion(cameraService->getDeviceVersion(cameraId)),
mDeviceActive(false)
{
ALOGI("Camera %d: Opened. Client: %s (PID %d, UID %d)", cameraId, String8(clientPackageName).string(), clientPid, clientUid);
mInitialClientPid = clientPid;
mDevice = new Camera3Device(cameraId);
LOG_ALWAYS_FATAL_IF(mDevice == 0, "Device should never be NULL here.");
}Camera3Device的有参构造 @ frameworks/av/services/camera/libcameraservice/device3/Camera3Device.cpp
cpp
Camera3Device::Camera3Device(int id):
mId(id),
mIsConstrainedHighSpeedConfiguration(false),
mHal3Device(NULL),
mStatus(STATUS_UNINITIALIZED),
mStatusWaiters(0),
mUsePartialResult(false),
mNumPartialResults(1),
mTimestampOffset(0),
mNextResultFrameNumber(0),
mNextReprocessResultFrameNumber(0),
mNextShutterFrameNumber(0),
mNextReprocessShutterFrameNumber(0),
mListener(NULL)
{
ATRACE_CALL();
camera3_callback_ops::notify = &sNotify;
camera3_callback_ops::process_capture_result = &sProcessCaptureResult;
ALOGV("%s: Created device for camera %d", __FUNCTION__, id);
}2.2.3.2 [Camera2Client] Camera2Client初始化 client->initialize(mModule))
- 1 Camera2ClientBase::initialize里面会调用 Camera3Device::initialize 对/dev/videox 调备节点进行初始化，获取对应的设备的opt 操作函数
- 2 初始化 Camera 默认参数
- 3 创建 Camera 运行时的六大线程
- 3.1 StreamingProcessor：用来处理preview和录像 stream的线程。
- 3.2 FrameProcessor：用来处理3A和人脸识别的线程。
- 3.3 CaptureSequencer：拍照流程状态机线程，拍照的场景非常多，后面会发出状态机的运转流程。
- 3.4 JpegProcessor：用来处理拍照 jpeg stream 线程
- 3.5 ZslProcessor3：这个处理零延时zsl stream使用的线程
- 3.6 mCallbackProcessor：处理callback的线程，主要包含对 callback stream 的创建函数 updateStream()以及处理 HAL 层传上来的 callback stream 的线程
@ frameworks/av/services/camera/libcameraservice/api1/Camera2Client.cpp
cpp
status_t Camera2Client::initialize(CameraModule *module)
{
ATRACE_CALL();
ALOGV("%s: Initializing client for camera %d", __FUNCTION__, mCameraId);
status_t res;
// 1. Camera2ClientBase::initialize调用 Camera3Device::initialize 进行设备初始化,获取对应的 camera device 的opt 操作函数
res = Camera2ClientBase::initialize(module);
==============>
@ frameworks/av/services/camera/libcameraservice/device3/Camera3Device.cpp
mDevice->initialize(module);
mDevice->setNotifyCallback(weakThis);
<==============
// 2. 初始化 Camera 默认参数
{
SharedParameters::Lock l(mParameters);
res = l.mParameters.initialize(&(mDevice->info()), mDeviceVersion);
================>
+ @ frameworks/av/services/camera/libcameraservice/api1/client2/Parameters.cpp
+ status_t Parameters::initialize(const CameraMetadata *info, int deviceVersion) {
+ ......
+ videoWidth = previewWidth;
+ videoHeight = previewHeight;
+ params.setPreviewSize(previewWidth, previewHeight);
+ params.setVideoSize(videoWidth, videoHeight);
+ params.set(CameraParameters::KEY_PREFERRED_PREVIEW_SIZE_FOR_VIDEO,
+ String8::format("%dx%d", previewWidth, previewHeight));
+ params.set(CameraParameters::KEY_SUPPORTED_PREVIEW_FORMATS, supportedPreviewFormats);
+ ...... 省略一系列 参数初始化代码
<================
}
String8 threadName;
// 3. 创建 Camera 运行时的六大线程
// 3.1 StreamingProcessor：用来处理preview和录像 stream的线程。
mStreamingProcessor = new StreamingProcessor(this);
threadName = String8::format("C2-%d-StreamProc", mCameraId);
mFrameProcessor->run(threadName.string());
// 3.2 FrameProcessor：用来处理3A和人脸识别的线程。
mFrameProcessor = new FrameProcessor(mDevice, this);
threadName = String8::format("C2-%d-FrameProc",mCameraId);
mFrameProcessor->run(threadName.string());
// 3.3 CaptureSequencer：拍照流程状态机线程，拍照的场景非常多，后面会发出状态机的运转流程。
mCaptureSequencer = new CaptureSequencer(this);
threadName = String8::format("C2-%d-CaptureSeq",mCameraId);
mCaptureSequencer->run(threadName.string());
// 3.4 JpegProcessor：用来处理拍照 jpeg stream 线程
mJpegProcessor = new JpegProcessor(this, mCaptureSequencer);
threadName = String8::format("C2-%d-JpegProc",mCameraId);
mJpegProcessor->run(threadName.string());
// 3.5 ZslProcessor3：这个处理零延时zsl stream使用的线程
mZslProcessor = new ZslProcessor(this, mCaptureSequencer);
threadName = String8::format("C2-%d-ZslProc",mCameraId);
mZslProcessor->run(threadName.string());
// 3.6 mCallbackProcessor：处理callback的线程，主要包含对 callback stream 的创建函数 updateStream()以及处理 HAL 层传上来的 callback stream 的线程
mCallbackProcessor = new CallbackProcessor(this);
threadName = String8::format("C2-%d-CallbkProc",mCameraId);
mCallbackProcessor->run(threadName.string());
return OK;
}2.2.3.2.1 [Camera3Device] Camera device 初始化 mDevice->initialize(module)
- 1 创建session
- 2 调用CameraProviderManager的opensession方法 @frameworks/av/services/camera/libcameraservice/device3/Camera3Device.cpp
cpp
status_t Camera3Device::initialize(sp<CameraProviderManager> manager, const String8& monitorTags) {
ATRACE_CALL();
Mutex::Autolock il(mInterfaceLock);
Mutex::Autolock l(mLock);
ALOGE("sundpmy_ %s: Initializing HIDL device for camera %s", __FUNCTION__, mId.string());
if (mStatus != STATUS_UNINITIALIZED) {
CLOGE("Already initialized!");
return INVALID_OPERATION;
}
if (manager == nullptr) return INVALID_OPERATION;
sp<ICameraDeviceSession> session;
ATRACE_BEGIN("CameraHal::openSession");
ALOGE("sundpmy_ manager->openSession");
status_t res = manager->openSession(mId.string(), this,
/*out*/ &session);
ATRACE_END();
if (res != OK) {
SET_ERR_L("Could not open camera session: %s (%d)", strerror(-res), res);
return res;
}
......
}2.2.3.2.2 [CameraProviderManager] manager->openSession
- 1 根据CameraDevice的版本，从所有Provider中，找到对应的DeviceInfo
- 2 根据刚刚deviceInfo中对应的provider的信息，获取到对应CameraProvider服务 @frameworks/av/services/camera/libcameraservice/common/CameraProviderManager.cpp
cpp
status_t CameraProviderManager::openSession(const std::string &id,
const sp<device::V3_2::ICameraDeviceCallback>& callback,
/*out*/
sp<device::V3_2::ICameraDeviceSession> *session) {
std::lock_guard<std::mutex> lock(mInterfaceMutex);
// 根据CameraDevice的版本，从所有Provider中，找到对应的DeviceInfo
auto deviceInfo = findDeviceInfoLocked(id,
/*minVersion*/ {3,0}, /*maxVersion*/ {4,0});
if (deviceInfo == nullptr) return NAME_NOT_FOUND;
// 根据刚刚deviceInfo中对应的provider的信息，获取到对应CameraProvider服务
auto *deviceInfo3 = static_cast<ProviderInfo::DeviceInfo3*>(deviceInfo);
const sp<provider::V2_4::ICameraProvider> provider =
deviceInfo->mParentProvider->startProviderInterface();
if (provider == nullptr) {
return DEAD_OBJECT;
}
saveRef(DeviceMode::CAMERA, id, provider);
Status status;
hardware::Return<void> ret;
// 通过CameraProvider的getCameraDeviceInterface_V3_x()实例化一个CameraDevice。这一步是通过HIDL调用到了Hal层
auto interface = deviceInfo3->startDeviceInterface<
CameraProviderManager::ProviderInfo::DeviceInfo3::InterfaceT>();
if (interface == nullptr) {
return DEAD_OBJECT;
}
ALOGE("sundpmy_ openSession");
// 这个interface就是前面startDeviceInterface()得到的CameraDevice，这里是要通过CameraDevicce::open()创建一个有效的CameraDeviceSession。这一步也是通过HIDL调用到了HAL
ret = interface->open(callback, [&status, &session]
(Status s, const sp<device::V3_2::ICameraDeviceSession>& cameraSession) {
status = s;
if (status == Status::OK) {
*session = cameraSession;
}
});
if (!ret.isOk()) {
removeRef(DeviceMode::CAMERA, id);
ALOGE("%s: Transaction error opening a session for camera device %s: %s",
__FUNCTION__, id.c_str(), ret.description().c_str());
return DEAD_OBJECT;
}
return mapToStatusT(status);
}2.2.3.3 [CameraDevice] CameraDevice::open
- 1 通过CameraModule的对象mModule继续open
- 2 通过CameraModule的对象mModule调用getCameraInfo得到camera的一些信息
- 3 创建CameraDeviceSession @hardware/interfaces/camera/device/3.2/default/CameraDevice.cpp
cpp
Return<void> CameraDevice::open(const sp<ICameraDeviceCallback>& callback,
ICameraDevice::open_cb _hidl_cb) {
Status status = initStatus();
sp<CameraDeviceSession> session = nullptr;
ALOGE("sundpmy_ 3.2 CameraDevice::open");
if (callback == nullptr) {
ALOGE("%s: cannot open camera %s. callback is null!",
__FUNCTION__, mCameraId.c_str());
_hidl_cb(Status::ILLEGAL_ARGUMENT, nullptr);
return Void();
}
if (status != Status::OK) {
// Provider will never pass initFailed device to client, so
// this must be a disconnected camera
ALOGE("%s: cannot open camera %s. camera is disconnected!",
__FUNCTION__, mCameraId.c_str());
_hidl_cb(Status::CAMERA_DISCONNECTED, nullptr);
return Void();
} else {
mLock.lock();
ALOGE("sundpmy_%s: Initializing device for camera %d", __FUNCTION__, mCameraIdInt);
session = mSession.promote();
if (session != nullptr && !session->isClosed()) {
ALOGE("%s: cannot open an already opened camera!", __FUNCTION__);
mLock.unlock();
_hidl_cb(Status::CAMERA_IN_USE, nullptr);
return Void();
}
/** Open HAL device */
status_t res;
camera3_device_t *device;
ATRACE_BEGIN("camera3->open");
//通过的CameraModule的对象mModule继续open
res = mModule->open(mCameraId.c_str(),
reinterpret_cast<hw_device_t**>(&device));
ATRACE_END();
if (res != OK) {
ALOGE("%s: cannot open camera %s!", __FUNCTION__, mCameraId.c_str());
mLock.unlock();
_hidl_cb(getHidlStatus(res), nullptr);
return Void();
}
/** Cross-check device version */
if (device->common.version < CAMERA_DEVICE_API_VERSION_3_2) {
ALOGE("%s: Could not open camera: "
"Camera device should be at least %x, reports %x instead",
__FUNCTION__,
CAMERA_DEVICE_API_VERSION_3_2,
device->common.version);
device->common.close(&device->common);
mLock.unlock();
_hidl_cb(Status::ILLEGAL_ARGUMENT, nullptr);
return Void();
}
struct camera_info info;
//通过CameraModule的对象mModule调用getCameraInfo得到camera的一些信息
res = mModule->getCameraInfo(mCameraIdInt, &info);
if (res != OK) {
ALOGE("%s: Could not open camera: getCameraInfo failed", __FUNCTION__);
device->common.close(&device->common);
mLock.unlock();
_hidl_cb(Status::ILLEGAL_ARGUMENT, nullptr);
return Void();
}
//创建CameraDeviceSession
session = createSession(
device, info.static_camera_characteristics, callback);
if (session == nullptr) {
ALOGE("%s: camera device session allocation failed", __FUNCTION__);
mLock.unlock();
_hidl_cb(Status::INTERNAL_ERROR, nullptr);
return Void();
}
if (session->isInitFailed()) {
ALOGE("%s: camera device session init failed", __FUNCTION__);
session = nullptr;
mLock.unlock();
_hidl_cb(Status::INTERNAL_ERROR, nullptr);
return Void();
}
mSession = session;
IF_ALOGV() {
session->getInterface()->interfaceChain([](
::android::hardware::hidl_vec<::android::hardware::hidl_string> interfaceChain) {
ALOGV("Session interface chain:");
for (const auto& iface : interfaceChain) {
ALOGV(" %s", iface.c_str());
}
});
}
mLock.unlock();
}
_hidl_cb(status, session->getInterface());
return Void();
} 2.2.3.4 [CameraModule] CameraModule::open
@hardware/interfaces/camera/common/1.0/default/CameraModule.cpp
cpp
int CameraModule::open(const char* id, struct hw_device_t** device) {
int res;
ATRACE_BEGIN("camera_module->open");
res = filterOpenErrorCode(mModule->common.methods->open(&mModule->common, id, device));
ATRACE_END();
return res;
}filterOpenErrorCode(mModule->common.methods->open(&mModule->common, id, device));
的参数mModule->common.methods->open(&mModule->common, id, device)
首先关注一下mModule,它是在CameraModule构造的时候赋值的
cpp
bool LegacyCameraProviderImpl_2_4::initialize() {
camera_module_t *rawModule;
int err = hw_get_module(CAMERA_HARDWARE_MODULE_ID,
(const hw_module_t **)&rawModule);
if (err < 0) {
ALOGE("Could not load camera HAL module: %d (%s)", err, strerror(-err));
return true;
}
//CameraModule构造的时候赋值
mModule = new CameraModule(rawModule);
err = mModule->init();
if (err != OK) {
ALOGE("Could not initialize camera HAL module: %d (%s)", err, strerror(-err));
mModule.clear();
return true;
}
ALOGI("Loaded \"%s\" camera module", mModule->getModuleName());
// Setup vendor tags here so HAL can setup vendor keys in camera characteristics
VendorTagDescriptor::clearGlobalVendorTagDescriptor();
if (!setUpVendorTags()) {
ALOGE("%s: Vendor tag setup failed, will not be available.", __FUNCTION__);
}
......
}2.2.3.4.1 [hardware] camera_module_t
@hardware/qcom/camera/QCamera2/QCamera2Hal.cpp
cpp
static hw_module_t camera_common = {
.tag = HARDWARE_MODULE_TAG,
.module_api_version = CAMERA_MODULE_API_VERSION_2_4,
.hal_api_version = HARDWARE_HAL_API_VERSION,
.id = CAMERA_HARDWARE_MODULE_ID,
.name = "QCamera Module",
.author = "Qualcomm Innovation Center Inc",
.methods = &qcamera::QCamera2Factory::mModuleMethods,
.dso = NULL,
.reserved = {0}
};
camera_module_t HAL_MODULE_INFO_SYM = {
.common = camera_common,
.get_number_of_cameras = qcamera::QCamera2Factory::get_number_of_cameras,
.get_camera_info = qcamera::QCamera2Factory::get_camera_info,
.set_callbacks = qcamera::QCamera2Factory::set_callbacks,
.get_vendor_tag_ops = qcamera::QCamera3VendorTags::get_vendor_tag_ops,
.open_legacy = (qcamera::QCameraCommon::needHAL1Support()) ?
qcamera::QCamera2Factory::open_legacy : NULL,
.set_torch_mode = qcamera::QCamera2Factory::set_torch_mode,
.init = NULL,
.reserved = {0}
};mModule->common.methods->open(&mModule->common, id, device)的open，
就是：
camera_common.&qcamera::QCamera2Factory::mModuleMethods.open
即：camera_device_open
cpp
struct hw_module_methods_t QCamera2Factory::mModuleMethods = {
.open = QCamera2Factory::camera_device_open,
};2.2.3.5 [Hardware] 打开设备 QCamera2Factory::cameraDeviceOpen()
@ hardware/qcom/camera/QCamera2/QCamera2Factory.cpp
cpp
int QCamera2Factory::cameraDeviceOpen(int camera_id, struct hw_device_t **hw_device)
{
LOGI("Open camera id %d API version %d",camera_id, mHalDescriptors[camera_id].device_version);
if ( mHalDescriptors[camera_id].device_version == CAMERA_DEVICE_API_VERSION_3_0 ) {
CAMSCOPE_INIT(CAMSCOPE_SECTION_HAL);
QCamera3HardwareInterface *hw = new QCamera3HardwareInterface(mHalDescriptors[camera_id].cameraId, mCallbacks);
rc = hw->openCamera(hw_device);
}
#ifdef QCAMERA_HAL1_SUPPORT
else if (mHalDescriptors[camera_id].device_version == CAMERA_DEVICE_API_VERSION_1_0) {
QCamera2HardwareInterface *hw = new QCamera2HardwareInterface((uint32_t)camera_id);
rc = hw->openCamera(hw_device);
}
#endif
return rc;
}初始化 QCamera3HardwareInterface() 可以不看 @ hardware/qcom/camera/QCamera2/HAL3/QCamera3HWI.cpp
cpp
QCamera3HardwareInterface::QCamera3HardwareInterface(uint32_t cameraId, const camera_module_callbacks_t *callbacks)
: mCameraId(cameraId),
mCameraHandle(NULL),
mCameraInitialized(false),
mCallbacks(callbacks),
...... //省略一系列Camera 初始化默认值
{
// 1. 获取HAL 层 log 等级
getLogLevel();
=========>
property_get("persist.camera.hal.debug", prop, "0");
property_get("persist.camera.kpi.debug", prop, "0");
property_get("persist.camera.global.debug", prop, "0");
mCommon.init(gCamCapability[cameraId]);
mCameraDevice.common.tag = HARDWARE_DEVICE_TAG;
mCameraDevice.common.version = CAMERA_DEVICE_API_VERSION_3_4;
mCameraDevice.common.close = close_camera_device;
mCameraDevice.ops = &mCameraOps;
===⇒ @ hardware/qcom/camera/QCamera2/HAL3/QCamera3HWI.cpp
mCameraDevice.priv = this;
gCamCapability[cameraId]->version = CAM_HAL_V3;
// TODO: hardcode for now until mctl add support for min_num_pp_bufs
//TBD - To see if this hardcoding is needed. Check by printing if this is filled by mctl to 3
gCamCapability[cameraId]->min_num_pp_bufs = 3;
pthread_condattr_t mCondAttr;
pthread_condattr_init(&mCondAttr);
pthread_condattr_setclock(&mCondAttr, CLOCK_MONOTONIC);
pthread_cond_init(&mBuffersCond, &mCondAttr);
pthread_cond_init(&mRequestCond, &mCondAttr);
pthread_cond_init(&mHdrRequestCond, &mCondAttr);
pthread_condattr_destroy(&mCondAttr);
mPendingLiveRequest = 0;
mCurrentRequestId = -1;
pthread_mutex_init(&mMutex, NULL);
for (size_t i = 0; i < CAMERA3_TEMPLATE_COUNT; i++)
mDefaultMetadata[i] = NULL;
// Getting system props of different kinds
char prop[PROPERTY_VALUE_MAX];
memset(prop, 0, sizeof(prop));
// 获取 persist.camera.raw.dump，是否使能 RAW dump 功能
property_get("persist.camera.raw.dump", prop, "0");
mEnableRawDump = atoi(prop);
// 获取 persist.camera.hal3.force.hdr，是否使能 hdr 功能
property_get("persist.camera.hal3.force.hdr", prop, "0");
mForceHdrSnapshot = atoi(prop);
if (mEnableRawDump)
LOGD("Raw dump from Camera HAL enabled");
memset(&mInputStreamInfo, 0, sizeof(mInputStreamInfo));
memset(mLdafCalib, 0, sizeof(mLdafCalib));
memset(prop, 0, sizeof(prop));
property_get("persist.camera.tnr.preview", prop, "0");
m_bTnrPreview = (uint8_t)atoi(prop);
memset(prop, 0, sizeof(prop));
property_get("persist.camera.swtnr.preview", prop, "1");
m_bSwTnrPreview = (uint8_t)atoi(prop);
memset(prop, 0, sizeof(prop));
property_get("persist.camera.tnr.video", prop, "0");
m_bTnrVideo = (uint8_t)atoi(prop);
memset(prop, 0, sizeof(prop));
property_get("persist.camera.avtimer.debug", prop, "0");
m_debug_avtimer = (uint8_t)atoi(prop);
LOGI("AV timer enabled: %d", m_debug_avtimer);
memset(prop, 0, sizeof(prop));
property_get("persist.camera.cacmode.disable", prop, "0");
m_cacModeDisabled = (uint8_t)atoi(prop);
mRdiModeFmt = gCamCapability[mCameraId]->rdi_mode_stream_fmt;
//Load and read GPU library.
lib_surface_utils = NULL;
LINK_get_surface_pixel_alignment = NULL;
mSurfaceStridePadding = CAM_PAD_TO_32;
// 打开 libadreno_utils.so
lib_surface_utils = dlopen("libadreno_utils.so", RTLD_NOW);
if (lib_surface_utils) {
*(void **)&LINK_get_surface_pixel_alignment =
dlsym(lib_surface_utils, "get_gpu_pixel_alignment");
if (LINK_get_surface_pixel_alignment) {
mSurfaceStridePadding = LINK_get_surface_pixel_alignment();
}
dlclose(lib_surface_utils);
}
if (gCamCapability[cameraId]->is_quadracfa_sensor) {
LOGI("Sensor support Quadra CFA mode");
m_bQuadraCfaSensor = true;
}
m_bQuadraCfaRequest = false;
m_bQuadraSizeConfigured = false;
memset(&mStreamList, 0, sizeof(camera3_stream_configuration_t));
}接下来，调用 hw->openCamera(hw_device); @ hardware/qcom/camera/QCamera2/HAL3/QCamera3HWI.cpp
cpp
int QCamera3HardwareInterface::openCamera(struct hw_device_t **hw_device)
{
......
if (mState != CLOSED) {
*hw_device = NULL;
return PERMISSION_DENIED;
}
mPerfLockMgr.acquirePerfLock(PERF_LOCK_OPEN_CAMERA);
LOGI("[KPI Perf]: E PROFILE_OPEN_CAMERA camera id %d",mCameraId);
rc = openCamera();
if (rc == 0) {
*hw_device = &mCameraDevice.common;
} else {
*hw_device = NULL;
}
LOGI("[KPI Perf]: X PROFILE_OPEN_CAMERA camera id %d, rc: %d", mCameraId, rc);
if (rc == NO_ERROR) {
mState = OPENED;
}
return rc;
}接下来调用 int QCamera3HardwareInterface::openCamera() @ hardware/qcom/camera/QCamera2/HAL3/QCamera3HWI.cpp
cpp
int QCamera3HardwareInterface::openCamera()
{
KPI_ATRACE_CAMSCOPE_CALL(CAMSCOPE_HAL3_OPENCAMERA);
if (mCameraHandle) {
LOGE("Failure: Camera already opened");
return ALREADY_EXISTS;
}
rc = QCameraFlash::getInstance().reserveFlashForCamera(mCameraId);
if (rc < 0) {
LOGE("Failed to reserve flash for camera id: %d",
mCameraId);
return UNKNOWN_ERROR;
}
rc = camera_open((uint8_t)mCameraId, &mCameraHandle);
rc = mCameraHandle->ops->register_event_notify(mCameraHandle->camera_handle, camEvtHandle, (void *)this);
mExifParams.debug_params = (mm_jpeg_debug_exif_params_t *) malloc (sizeof(mm_jpeg_debug_exif_params_t));
if (mExifParams.debug_params) {
memset(mExifParams.debug_params, 0, sizeof(mm_jpeg_debug_exif_params_t));
} else {
LOGE("Out of Memory. Allocation failed for 3A debug exif params");
return NO_MEMORY;
}
mFirstConfiguration = true;
......
}2.2.3.5.1 camera_open((uint8_t)mCameraId, &mCameraHandle)
打开Camera 成功后，hardware 层中将Camera 所有信息保存在 g_cam_ctrl.cam_obj[cam_idx] 中，同时返回对应的camera 的opt 操作函数
@ hardware/qcom/camera/QCamera2/stack/mm-camera-interface/src/mm_camera_interface.c
cpp
int32_t camera_open(uint8_t camera_idx, mm_camera_vtbl_t **camera_vtbl)
{
int32_t rc = 0;
mm_camera_obj_t *cam_obj = NULL;
uint32_t cam_idx = camera_idx;
uint32_t aux_idx = 0;
uint8_t is_multi_camera = 0;
#ifdef QCAMERA_REDEFINE_LOG
mm_camera_debug_open();
#endif
LOGD("E camera_idx = %d\n", camera_idx);
//判断是否是双摄camera
if (is_dual_camera_by_idx(camera_idx)) {
is_multi_camera = 1;
cam_idx = mm_camera_util_get_handle_by_num(0,g_cam_ctrl.cam_index[camera_idx]);
aux_idx = (get_aux_camera_handle(g_cam_ctrl.cam_index[camera_idx]) >> MM_CAMERA_HANDLE_SHIFT_MASK);
LOGH("Dual Camera: Main ID = %d Aux ID = %d", cam_idx, aux_idx);
}
pthread_mutex_lock(&g_intf_lock);
/* opened already */
if(NULL != g_cam_ctrl.cam_obj[cam_idx] && g_cam_ctrl.cam_obj[cam_idx]->ref_count != 0) {
pthread_mutex_unlock(&g_intf_lock);
LOGE("Camera %d is already open", cam_idx);
return -EBUSY;
}
cam_obj = (mm_camera_obj_t *)malloc(sizeof(mm_camera_obj_t));
/* 初始化cam_obj的信息*/
memset(cam_obj, 0, sizeof(mm_camera_obj_t));
cam_obj->ctrl_fd = -1;
cam_obj->ds_fd = -1;
cam_obj->ref_count++;
cam_obj->my_num = 0;
cam_obj->my_hdl = mm_camera_util_generate_handler(cam_idx);
cam_obj->vtbl.camera_handle = cam_obj->my_hdl; /* set handler */
cam_obj->vtbl.ops = &mm_camera_ops;
pthread_mutex_init(&cam_obj->cam_lock, NULL);
pthread_mutex_init(&cam_obj->muxer_lock, NULL);
/* unlock global interface lock, if not, in dual camera use case,
* current open will block operation of another opened camera obj*/
pthread_mutex_lock(&cam_obj->cam_lock);
pthread_mutex_unlock(&g_intf_lock);
//here
rc = mm_camera_open(cam_obj);
if (is_multi_camera) {
/*Open Aux camer's*/
pthread_mutex_lock(&g_intf_lock);
if(NULL != g_cam_ctrl.cam_obj[aux_idx] &&
g_cam_ctrl.cam_obj[aux_idx]->ref_count != 0) {
pthread_mutex_unlock(&g_intf_lock);
LOGE("Camera %d is already open", aux_idx);
rc = -EBUSY;
} else {
pthread_mutex_lock(&cam_obj->muxer_lock);
pthread_mutex_unlock(&g_intf_lock);
rc = mm_camera_muxer_camera_open(aux_idx, cam_obj);
}
}
LOGH("Open succeded: handle = %d", cam_obj->vtbl.camera_handle);
g_cam_ctrl.cam_obj[cam_idx] = cam_obj;
*camera_vtbl = &cam_obj->vtbl;
return 0;
}继续跟进分析：
终于来到最底层的实现了，mm_camera_open 主要工作是填充 my_obj，并且启动、初始化一些线程相关的东西，关于线程的部分我这里就省略掉了。
此时Open 对应的 /dev/video 节点，获得对应的session_id，创建好相关的 socket ，最终所有信息，保存在 mm_camera_obj_t * cam_obj节构体中。
@ hardware/qcom/camera/QCamera2/stack/mm-camera-interface/src/mm_camera.c
cpp
int32_t mm_camera_open(mm_camera_obj_t *my_obj)
{
char dev_name[MM_CAMERA_DEV_NAME_LEN];
int8_t n_try=MM_CAMERA_DEV_OPEN_TRIES;
uint8_t sleep_msec=MM_CAMERA_DEV_OPEN_RETRY_SLEEP;
int cam_idx = 0;
const char *dev_name_value = NULL;
LOGD("begin\n");
dev_name_value = mm_camera_util_get_dev_name_by_num(my_obj->my_num, my_obj->my_hdl);
snprintf(dev_name, sizeof(dev_name), "/dev/%s",dev_name_value);
sscanf(dev_name, "/dev/video%d", &cam_idx);
LOGD("dev name = %s, cam_idx = %d", dev_name, cam_idx);
do{
n_try--;
errno = 0;
my_obj->ctrl_fd = open(dev_name, O_RDWR | O_NONBLOCK);
l_errno = errno;
LOGD("ctrl_fd = %d, errno == %d", my_obj->ctrl_fd, l_errno);
if((my_obj->ctrl_fd >= 0) || (errno != EIO && errno != ETIMEDOUT) || (n_try <= 0 )) {
break;
}
LOGE("Failed with %s error, retrying after %d milli-seconds", strerror(errno), sleep_msec);
usleep(sleep_msec * 1000U);
}while (n_try > 0);
mm_camera_get_session_id(my_obj, &my_obj->sessionid);
LOGH("Camera Opened id = %d sessionid = %d", cam_idx, my_obj->sessionid);
#ifdef DAEMON_PRESENT
/* open domain socket*/
n_try = MM_CAMERA_DEV_OPEN_TRIES;
do {
n_try--;
my_obj->ds_fd = mm_camera_socket_create(cam_idx, MM_CAMERA_SOCK_TYPE_UDP);
l_errno = errno;
LOGD("ds_fd = %d, errno = %d", my_obj->ds_fd, l_errno);
if((my_obj->ds_fd >= 0) || (n_try <= 0 )) {
LOGD("opened, break out while loop");
break;
}
LOGD("failed with I/O error retrying after %d milli-seconds", sleep_msec);
usleep(sleep_msec * 1000U);
} while (n_try > 0);
#else /* DAEMON_PRESENT */
cam_status_t cam_status;
cam_status = mm_camera_module_open_session(my_obj->sessionid,mm_camera_module_event_handler);
#endif /* DAEMON_PRESENT */
pthread_condattr_init(&cond_attr);
pthread_condattr_setclock(&cond_attr, CLOCK_MONOTONIC);
pthread_mutex_init(&my_obj->msg_lock, NULL);
pthread_mutex_init(&my_obj->cb_lock, NULL);
pthread_mutex_init(&my_obj->evt_lock, NULL);
pthread_cond_init(&my_obj->evt_cond, &cond_attr);
pthread_condattr_destroy(&cond_attr);
LOGD("Launch evt Thread in Cam Open");
snprintf(my_obj->evt_thread.threadName, THREAD_NAME_SIZE, "CAM_Dispatch");
mm_camera_cmd_thread_launch(&my_obj->evt_thread, mm_camera_dispatch_app_event, (void *)my_obj);
/* launch event poll thread
* we will add evt fd into event poll thread upon user first register for evt */
LOGD("Launch evt Poll Thread in Cam Open");
snprintf(my_obj->evt_poll_thread.threadName, THREAD_NAME_SIZE, "CAM_evntPoll");
mm_camera_poll_thread_launch(&my_obj->evt_poll_thread, MM_CAMERA_POLL_TYPE_EVT);
mm_camera_evt_sub(my_obj, TRUE);
/* unlock cam_lock, we need release global intf_lock in camera_open(),
* in order not block operation of other Camera in dual camera use case.*/
pthread_mutex_unlock(&my_obj->cam_lock);
LOGD("end (rc = %d)\n", rc);
return rc;
}2.2.3.5.2 Camera 操作节构体 cam_obj->vtbl.ops
cpp
@ hardware/qcom/camera/QCamera2/stack/mm-camera-interface/src/mm_camera_interface.c
static mm_camera_ops_t mm_camera_ops = {
.query_capability = mm_camera_intf_query_capability,
.register_event_notify = mm_camera_intf_register_event_notify,
.close_camera = mm_camera_intf_close,
.set_parms = mm_camera_intf_set_parms,
.get_parms = mm_camera_intf_get_parms,
.do_auto_focus = mm_camera_intf_do_auto_focus,
.cancel_auto_focus = mm_camera_intf_cancel_auto_focus,
.prepare_snapshot = mm_camera_intf_prepare_snapshot,
.start_zsl_snapshot = mm_camera_intf_start_zsl_snapshot,
.stop_zsl_snapshot = mm_camera_intf_stop_zsl_snapshot,
.map_buf = mm_camera_intf_map_buf,
.map_bufs = mm_camera_intf_map_bufs,
.unmap_buf = mm_camera_intf_unmap_buf,
.add_channel = mm_camera_intf_add_channel,
.delete_channel = mm_camera_intf_del_channel,
.get_bundle_info = mm_camera_intf_get_bundle_info,
.add_stream = mm_camera_intf_add_stream,
.link_stream = mm_camera_intf_link_stream,
.delete_stream = mm_camera_intf_del_stream,
.config_stream = mm_camera_intf_config_stream,
.qbuf = mm_camera_intf_qbuf,
.cancel_buffer = mm_camera_intf_cancel_buf,
.get_queued_buf_count = mm_camera_intf_get_queued_buf_count,
.map_stream_buf = mm_camera_intf_map_stream_buf,
.map_stream_bufs = mm_camera_intf_map_stream_bufs,
.unmap_stream_buf = mm_camera_intf_unmap_stream_buf,
.set_stream_parms = mm_camera_intf_set_stream_parms,
.get_stream_parms = mm_camera_intf_get_stream_parms,
.start_channel = mm_camera_intf_start_channel,
.stop_channel = mm_camera_intf_stop_channel,
.request_super_buf = mm_camera_intf_request_super_buf,
.cancel_super_buf_request = mm_camera_intf_cancel_super_buf_request,
.flush_super_buf_queue = mm_camera_intf_flush_super_buf_queue,
.configure_notify_mode = mm_camera_intf_configure_notify_mode,
.process_advanced_capture = mm_camera_intf_process_advanced_capture,
.get_session_id = mm_camera_intf_get_session_id,
.set_dual_cam_cmd = mm_camera_intf_set_dual_cam_cmd,
.flush = mm_camera_intf_flush,
.register_stream_buf_cb = mm_camera_intf_register_stream_buf_cb,
.register_frame_sync = mm_camera_intf_reg_frame_sync,
.handle_frame_sync_cb = mm_camera_intf_handle_frame_sync_cb
};2.2.3.5.3 [Hardware] 初始化Framewroks层的Callback 函数 QCamera3HardwareInterface::initialize( )
cpp
@ hardware/qcom/camera/QCamera2/HAL3/QCamera3HWI.cpp
/*===========================================================================
* FUNCTION : initialize
* DESCRIPTION: Initialize frameworks callback functions
* @callback_ops : callback function to frameworks
*==========================================================================*/
int QCamera3HardwareInterface::initialize(const struct camera3_callback_ops *callback_ops)
{
ATRACE_CAMSCOPE_CALL(CAMSCOPE_HAL3_INIT);
LOGI("E :mCameraId = %d mState = %d", mCameraId, mState);
rc = initParameters();
mCallbackOps = callback_ops;
=====> 该Callback 是从 frameworks/av/services/camera/libcameraservice/CameraService.cpp 中传递下来的
if (mModule->getModuleApiVersion() >= CAMERA_MODULE_API_VERSION_2_1) {
mModule->setCallbacks(this);
}
mChannelHandle = mCameraHandle->ops->add_channel( mCameraHandle->camera_handle, NULL, NULL, this);
mCameraInitialized = true;
mState = INITIALIZED;
LOGI("X");
return 0;
}2.2.4 EventHandler( )
在 EventHandler 中，根据具体的事件，调用不同的 callback 函数
cpp
@ frameworks/base/core/java/android/hardware/Camera.java
private class EventHandler extends Handler
{
private final Camera mCamera;
public EventHandler(Camera c, Looper looper) {
super(looper);
mCamera = c;
}
@Override
public void handleMessage(Message msg) {
switch(msg.what) {
case CAMERA_MSG_SHUTTER:
if (mShutterCallback != null) {
mShutterCallback.onShutter();
}
return;
case CAMERA_MSG_RAW_IMAGE:
if (mRawImageCallback != null) {
mRawImageCallback.onPictureTaken((byte[])msg.obj, mCamera);
}
return;
case CAMERA_MSG_COMPRESSED_IMAGE:
if (mJpegCallback != null) {
mJpegCallback.onPictureTaken((byte[])msg.obj, mCamera);
}
return;
case CAMERA_MSG_PREVIEW_FRAME:
PreviewCallback pCb = mPreviewCallback;
if (pCb != null) {
if (mOneShot) {
// Clear the callback variable before the callback
// in case the app calls setPreviewCallback from
// the callback function
mPreviewCallback = null;
} else if (!mWithBuffer) {
// We're faking the camera preview mode to prevent
// the app from being flooded with preview frames.
// Set to oneshot mode again.
setHasPreviewCallback(true, false);
}
pCb.onPreviewFrame((byte[])msg.obj, mCamera);
}
return;
case CAMERA_MSG_POSTVIEW_FRAME:
if (mPostviewCallback != null) {
mPostviewCallback.onPictureTaken((byte[])msg.obj, mCamera);
}
return;
case CAMERA_MSG_FOCUS:
AutoFocusCallback cb = null;
synchronized (mAutoFocusCallbackLock) {
cb = mAutoFocusCallback;
}
if (cb != null) {
boolean success = msg.arg1 == 0 ? false : true;
cb.onAutoFocus(success, mCamera);
}
return;
case CAMERA_MSG_ZOOM:
if (mZoomListener != null) {
mZoomListener.onZoomChange(msg.arg1, msg.arg2 != 0, mCamera);
}
return;
case CAMERA_MSG_PREVIEW_METADATA:
if (mFaceListener != null) {
mFaceListener.onFaceDetection((Face[])msg.obj, mCamera);
}
return;
case CAMERA_MSG_ERROR :
Log.e(TAG, "Error " + msg.arg1);
if (mErrorCallback != null) {
mErrorCallback.onError(msg.arg1, mCamera);
}
return;
case CAMERA_MSG_FOCUS_MOVE:
if (mAutoFocusMoveCallback != null) {
mAutoFocusMoveCallback.onAutoFocusMoving(msg.arg1 == 0 ? false : true, mCamera);
}
return;
/* ### QC ADD-ONS: START */
case CAMERA_MSG_STATS_DATA:
int statsdata[] = new int[257];
for(int i =0; i<257; i++ ) {
statsdata[i] = byteToInt( (byte[])msg.obj, i*4);
}
if (mCameraDataCallback != null) {
mCameraDataCallback.onCameraData(statsdata, mCamera);
}
return;
case CAMERA_MSG_META_DATA:
if (mCameraMetaDataCallback != null) {
mCameraMetaDataCallback.onCameraMetaData((byte[])msg.obj, mCamera);
}
return;
/* ### QC ADD-ONS: END */
default:
Log.e(TAG, "Unknown message type " + msg.what);
return;
}
}
}2.3 内核层msm_open
从上文的my_obj->ctrl_fd = open(dev_name, O_RDWR | O_NONBLOCK);
调用到内核：@kernel/msm-4.14/drivers/media/platform/msm/camera_v2/msm.c
cc
static int msm_open(struct file *filep)
{
int rc = -1;
unsigned long flags;
struct msm_video_device *pvdev = video_drvdata(filep);
DEBUG("enter");
if (WARN_ON(!pvdev))
return rc;
/* !!! only ONE open is allowed !!! */
if (atomic_cmpxchg(&pvdev->opened, 0, 1))
return -EBUSY;
spin_lock_irqsave(&msm_pid_lock, flags);
msm_pid = get_pid(task_pid(current));
spin_unlock_irqrestore(&msm_pid_lock, flags);
/* create event queue */
rc = v4l2_fh_open(filep);
if (rc < 0)
return rc;
spin_lock_irqsave(&msm_eventq_lock, flags);
msm_eventq = filep->private_data;
spin_unlock_irqrestore(&msm_eventq_lock, flags);
/* register msm_v4l2_pm_qos_request */
msm_pm_qos_add_request();
return rc;
}后面的流程就不看了。
至此，整个open Camera 流程就完了
3 OpenSession 流程分析
open过程中会 start session 大概流程如下：
3.1 mm-camera2框架
mm-camera架构有2个版本,我们这里研究的是新版本：
(1)最老的版本是有一个守护进程mm-qcamera-daemon的，
如msm8909平台，后来新版的架构改过，移除了这个守护进程，如msm8937(sdm429)平台。
(2) Android O 中，系统启动时，就会启动 CameraProvider 服务。它将 Camera HAL 从 cameraserver 进程中分离出来，做为一个独立进程 android.hardware.camera.provider@2.4-service 来控制 HAL。这两个进程之间经过 HIDL 机制进行通讯。
mm-camera代码位于 vendor/qcom/proprietary/mm-camera/mm-camera2 目录下，
在此目录下有 media-controller ，server-tuning ，server-imaging ，我们需要关注的是 media-controller 目录，整个树形结构如下：
|- mct ------应该就是camera的引擎() 里面包含了引擎、pipiline、bus、module、stream及event等定义及封装。
|- modules ------ 这里面就是划分好的一些模块代码，各模块大致功能如下 :
|- sensor ------ sensor 的驱动模块(src模块)
|- actuator_libs,actuators 马达基本配置以及效果参数
|- sensor_libs,chromatix camera模组基本配置以及效果参数，模组这块最重要的两部分
|- eeprom_libs,eeprom eeprom配置以及参数，现在基本不用
|- strobe_flash,led_flash strobe,led flash驱动
|- iface ------ ISP interface模块
|- isp ------ 主要是ISP的处理，其内部又包含了众多的模块(inter模块)
|- stats ------ 一些统计算法模块，如3A，ASD,AFD,IS,GRRO等数据统计的处理(sink模块)
|- pproc ------ post process处理(inter模块)
|- imglib ------ 主要是图片的一些后端处理，如HDR，人脸识别等(sink模块)
3.2 media controller线程
MCT线程是camera新架构的引擎部分，负责对管道的监控，由此来完成一个camera设备的控制运转。下面看的是mct controller线程的创建
3.2.1 mm_camera_module_open_session
Open阶段完成后，会继续opensession。
cc
@hardware/qcom/camera/QCamera2/stack/mm-camera-interface/src/mm_camera.c
int32_t mm_camera_open(mm_camera_obj_t *my_obj)
{
......
const char *dev_name_value = NULL;
dev_name_value = mm_camera_util_get_dev_name_by_num(my_obj->my_num,
my_obj->my_hdl);
snprintf(dev_name, sizeof(dev_name), "/dev/%s",
dev_name_value);
my_obj->ctrl_fd = open(dev_name, O_RDWR | O_NONBLOCK);
cam_status_t cam_status;
......
cam_status = mm_camera_module_open_session(my_obj->sessionid,
mm_camera_module_event_handler);
......
}@ hardware/qcom/camera/QCamera2/stack/mm-camera-interface/src/mm_camera_interface.c
cc
/*===========================================================================
* FUNCTION : mm_camera_module_open_session
*
* DESCRIPTION: wrapper function to call shim layer API to open session.
*
* PARAMETERS :
* @sessionid : sessionID to open session
* @evt_cb : Event callback function
*
* RETURN : int32_t type of status
* 0 -- success
* non-zero error code -- failure
*==========================================================================*/
cam_status_t mm_camera_module_open_session(int sessionid,
mm_camera_shim_event_handler_func evt_cb)
{
cam_status_t rc = -1;
if(g_cam_ctrl.cam_shim_ops.mm_camera_shim_open_session) {
rc = g_cam_ctrl.cam_shim_ops.mm_camera_shim_open_session(
sessionid, evt_cb);
}
return rc;
}g_cam_ctrl.cam_shim_ops.mm_camera_shim_open_session
cc
1 @hardware/qcom/camera/QCamera2/stack/mm-camera-interface/src/mm_camera_interface.c
static mm_camera_ctrl_t g_cam_ctrl;
2 @hardware/qcom/camera/QCamera2/stack/mm-camera-interface/inc/mm_camera.h
typedef struct {
int8_t num_cam;
mm_camera_shim_ops_t cam_shim_ops;
int8_t num_cam_to_expose;
char video_dev_name[MM_CAMERA_MAX_NUM_SENSORS][MM_CAMERA_DEV_NAME_LEN];
mm_camera_obj_t *cam_obj[MM_CAMERA_MAX_NUM_SENSORS];
struct camera_info info[MM_CAMERA_MAX_NUM_SENSORS];
cam_sync_type_t cam_type[MM_CAMERA_MAX_NUM_SENSORS];
cam_sync_mode_t cam_mode[MM_CAMERA_MAX_NUM_SENSORS];
uint8_t is_yuv[MM_CAMERA_MAX_NUM_SENSORS]; // 1=CAM_SENSOR_YUV, 0=CAM_SENSOR_RAW
uint32_t cam_index[MM_CAMERA_MAX_NUM_SENSORS]; //Actual cam index are stored in bits
} mm_camera_ctrl_t;
3 @hardware/qcom/camera/QCamera2/stack/common/mm_camera_shim.h
typedef struct {
cam_status_t (*mm_camera_shim_open_session) (int session,
mm_camera_shim_event_handler_func evt_cb);
int32_t (*mm_camera_shim_close_session)(int session);
int32_t (*mm_camera_shim_send_cmd)(cam_shim_packet_t *event);
} mm_camera_shim_ops_t;3.2.2 mct_shimlayer_process_module_init
上面其中的mm_camera_shim_open_session就是mct_shimlayer_start_session @vendor/qcom/proprietary/mm-camera/mm-camera2/media-controller/mct_shim_layer/mct_shim_layer.c
cc
int mct_shimlayer_process_module_init(mm_camera_shim_ops_t
*shim_ops_tbl)
{
...
shim_ops_tbl->mm_camera_shim_open_session = mct_shimlayer_start_session;
shim_ops_tbl->mm_camera_shim_close_session = mct_shimlayer_stop_session;
shim_ops_tbl->mm_camera_shim_send_cmd = mct_shimlayer_process_event;
...
}3.2.3 mct_shimlayer_start_session
@vendor/qcom/proprietary/mm-camera/mm-camera2/media-controller/mct_shim_layer/mct_shim_layer.c
1.创建mct_controller
c
cam_status_t mct_shimlayer_start_session(int session,
mm_camera_shim_event_handler_func event_cb)
{
int32_t enabled_savemem;
char savemem[128];
cam_status_t ret = CAM_STATUS_FAILED;
char prop[PROPERTY_VALUE_MAX];
int enable_memleak = 0;
//内存泄漏检查
#ifdef MEMLEAK_FLAG
property_get("persist.vendor.camera.memleak.enable", prop, "0");
enable_memleak = atoi(prop);
if (enable_memleak) {
CLOGH(CAM_MCT_MODULE, "Memory leak tracking enabled.");
enable_memleak_trace(0);
}
#endif
pthread_mutex_lock(&session_mutex);
property_get("vendor.camera.cameradaemon.SaveMemAtBoot", savemem, "0");
enabled_savemem = atoi(savemem);
if (enabled_savemem == 1) {
if (mct_shimlayer_module_init() == FALSE) {
pthread_mutex_unlock(&session_mutex);
return CAM_STATUS_FAILED;
}
}
//创建mct_controller
ret = mct_controller_new(modules, session, config_fd, event_cb);
if (ret == CAM_STATUS_BUSY || ret == CAM_STATUS_FAILED) {
pthread_mutex_unlock(&session_mutex);
CLOGE(CAM_SHIM_LAYER,"Session creation for session =%d failed with err %d",
session, ret);
/*Signalling memleak thread to print if any memory leak present */
#ifdef MEMLEAK_FLAG
if (enable_memleak) {
CLOGH(CAM_MCT_MODULE, "Signal to print memory leak");
if (pthread_mutex_trylock (&server_memleak_mut) == 0) {
server_memleak_event = PRINT_LEAK_MEMORY;
pthread_cond_signal(&server_memleak_con);
pthread_mutex_unlock (&server_memleak_mut);
}
}
#endif
return ret;
}
pthread_mutex_unlock(&session_mutex);
return ret;
}3.2.4 mct_controller_new
1.创建mct_pipeline
2.mct_pipeline 启动session @vendor/qcom/proprietary/mm-camera/mm-camera2/media-controller/mct/pipeline/mct_pipeline.c
cpp
cam_status_t mct_controller_new(mct_list_t *mods,
unsigned int session_idx, int serv_fd, void *event_cb)
{
mct_controller_t *mct = NULL;
mct = (mct_controller_t *)malloc(sizeof(mct_controller_t));
memset(mct, 0, sizeof(mct_controller_t));
//创建mct_pipeline
mct->pipeline = mct_pipeline_new(session_idx, mct);
...
//mct_pipeline 启动session
ret_type = mct_pipeline_start_session(mct->pipeline);
} 3.2.4.1 mct_pipeline_new
1.创建mct_pipeline
2.初始化pipeline的信息
cpp
mct_pipeline_t* mct_pipeline_new (unsigned int session_idx,
mct_controller_t *pController)
{
//创建mct_pipeline
mct_pipeline_t *pipeline;
pipeline = malloc(sizeof(mct_pipeline_t));
memset(pipeline, 0, sizeof(mct_pipeline_t));
//初始化pipeline的信息
}3.2.4.2 mct_pipeline_start_session
c
cam_status_t mct_pipeline_start_session(mct_pipeline_t *pipeline)
{
boolean rc;
int ret;
int rdi_standalone_streams = 0;
struct timespec timeToWait;
char prop[PROPERTY_VALUE_MAX];
CLOGE(CAM_MCT_MODULE, "sundp_ mct_pipeline_start_session\n");
if (!pipeline) {
CLOGE(CAM_MCT_MODULE, "NULL pipeline ptr");
return CAM_STATUS_FAILED;
}
property_get("persist.vendor.camera.mct.multirdi", prop, "0");
rdi_standalone_streams = atoi (prop);
CLOGE(CAM_MCT_MODULE, "sundp_ rdi_standalone_streams = %d\n",rdi_standalone_streams);
ATRACE_CAMSCOPE_BEGIN(CAMSCOPE_MCT_START_SESSION);
pthread_mutex_init(&pipeline->thread_data.mutex, NULL);
pthread_condattr_init(&pipeline->thread_data.condattr);
pthread_condattr_setclock(&pipeline->thread_data.condattr, CLOCK_MONOTONIC);
pthread_cond_init(&pipeline->thread_data.cond_v, &pipeline->thread_data.condattr);
pipeline->thread_data.started_num = 0;
pipeline->thread_data.modules_num = 0;
pipeline->thread_data.started_num_success = 0;
//获得module的数量，这里的module就是sensor，iface等等
rc = mct_list_traverse(pipeline->modules, mct_pipeline_get_module_num,
pipeline);
//开启module
rc &= mct_list_traverse(pipeline->modules, mct_pipeline_modules_start,
pipeline);
rc = mct_util_get_timeout(MCT_THREAD_TIMEOUT, &timeToWait);3.2.4.3 mct_pipeline_modules_start
主要通过调用pthread_create，创建6大线程：
pthread_create(sensor)
pthread_create(iface)
pthread_create(isp)
pthread_create(stats)
pthread_create(pproc)
pthread_create(imglib)
然后在start这些session
cc
static boolean mct_pipeline_modules_start(void *data1, void *data2)
{
int rc = 0;
pthread_attr_t attr;
char thread_name[20];
mct_pipeline_t *pipeline = (mct_pipeline_t *)data2;
mct_pipeline_thread_data_t *thread_data = &(pipeline->thread_data);
thread_data->module = (mct_module_t *)data1;
thread_data->session_id = pipeline->session;
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
pthread_mutex_lock(&thread_data->mutex);
CLOGE(CAM_MCT_MODULE,"sundp_ pthread_create\n");
//主要通过调用pthread_create，创建6大线程
rc = pthread_create(&pipeline->thread_data.pid, &attr,
&mct_pipeline_start_session_thread, (void *)thread_data);
snprintf(thread_name, sizeof(thread_name), "CAM_start%s",
MCT_MODULE_NAME(thread_data->module));
CLOGE(CAM_MCT_MODULE,"sundp_ %s\n",thread_name);
if(!rc) {
pthread_setname_np(pipeline->thread_data.pid,thread_name);
pthread_cond_wait(&thread_data->cond_v, &thread_data->mutex);
}
pthread_mutex_unlock(&thread_data->mutex);
return TRUE;
}3.2.4.4 mct_pipeline_start_session_thread
start_session
cpp
static void* mct_pipeline_start_session_thread(void *data)
{
mct_pipeline_thread_data_t *thread_data = (mct_pipeline_thread_data_t*)data;
mct_module_t *module = thread_data->module;
unsigned int session_id = thread_data->session_id;
boolean rc = FALSE;
ATRACE_BEGIN_SNPRINTF(30, "Camera:MCTModStart:%s",
MCT_MODULE_NAME(thread_data->module));
CLOGI(CAM_MCT_MODULE, "sundp_ E %s" , MCT_MODULE_NAME(thread_data->module));
pthread_mutex_lock(&thread_data->mutex);
pthread_cond_signal(&thread_data->cond_v);
pthread_mutex_unlock(&thread_data->mutex);
if (module->start_session) {
CLOGI(CAM_MCT_MODULE, "sudp_ Calling start_session on Module %s",
MCT_MODULE_NAME(module));
rc = module->start_session(module, session_id);
CLOGI(CAM_MCT_MODULE, "Module %s start_session rc = %d",
MCT_MODULE_NAME(module), rc);
}
pthread_mutex_lock(&thread_data->mutex);
thread_data->started_num++;
if (rc == TRUE)
thread_data->started_num_success++;
CLOGI(CAM_MCT_MODULE, "started_num = %d, success = %d",
thread_data->started_num, thread_data->started_num_success);
if(thread_data->started_num == thread_data->modules_num)
pthread_cond_signal(&thread_data->cond_v);
pthread_mutex_unlock(&thread_data->mutex);
ATRACE_END();
CLOGI(CAM_MCT_MODULE, "sundp_ X %s" , MCT_MODULE_NAME(module));
return NULL;
}3.3 else
后边的就不看了。到这open也open成功了。调用流程大概是
flowchart LR
mm_camera_open -->
open;
mm_camera_open --> mm_camera_module_open_session --> mct_shimlayer_start_session --> mct_controller_new
mct_controller_new --> mct_pipeline_new
mct_controller_new --> mct_pipeline_start_session
mct_pipeline_start_session --> mct_pipeline_get_module_num
mct_pipeline_start_session --> mct_pipeline_modules_start
mct_pipeline_modules_start --> sensor --> start_session
mct_pipeline_modules_start --> iface --> start_session
mct_pipeline_modules_start --> isp --> start_session
mct_pipeline_modules_start --> stats --> start_session
mct_pipeline_modules_start --> pproc --> start_session
d_cond_signal(&thread_data->cond_v);
pthread_mutex_unlock(&thread_data->mutex);
if (module->start_session) {
CLOGI(CAM_MCT_MODULE, "sudp_ Calling start_session on Module %s",
MCT_MODULE_NAME(module));
rc = module->start_session(module, session_id);
CLOGI(CAM_MCT_MODULE, "Module %s start_session rc = %d",
MCT_MODULE_NAME(module), rc);
}
pthread_mutex_lock(&thread_data->mutex);
thread_data->started_num++;
if (rc == TRUE)
thread_data->started_num_success++;
CLOGI(CAM_MCT_MODULE, "started_num = %d, success = %d",
thread_data->started_num, thread_data->started_num_success);
if(thread_data->started_num == thread_data->modules_num)
pthread_cond_signal(&thread_data->cond_v);
pthread_mutex_unlock(&thread_data->mutex);
ATRACE_END();
CLOGI(CAM_MCT_MODULE, "sundp_ X %s" , MCT_MODULE_NAME(module));
return NULL;
}
3.3 else
后边的就不看了。到这open也open成功了。调用流程大概是
mm_camera_open open mm_camera_module_open_session mct_shimlayer_start_session mct_controller_new mct_pipeline_new mct_pipeline_start_session mct_pipeline_get_module_num mct_pipeline_modules_start sensor start_session iface isp stats pproc imglib