[libcamera-devel] [PATCH v2 3/4] android: camera_hal_manager: Support camera hotplug
Umang Jain
email at uajain.com
Mon Aug 10 14:04:14 CEST 2020
Extend the support for camera hotplug from libcamera's CameraManager
to CameraHalManager. Use camera module callbacks to let the framework
know about the hotplug events and change the status of cameras being
being hotplugged or unplugged via camera_device_status_change().
Introduce a map camerasMap_ which book-keeps all cameras seen in the
past by the CameraHalManager. If the camera is seen for the first time,
a new id is assigned to it. If the camera has been seen before by the
manager, it's old id is reused. IDs for internal cameras start with
'0' and for external cameras, they start with '1000'. Note, for the
current implementation, we assume all UVC cameras are external cameras.
CameraDevice is now a shared object and cameras_ vector stores shared
pointers to CameraDevice. This is done in order to introduce reference
counting for CameraDevice objects - especially to handle hot-unplug
events. Both camerasMap_ and cameras_ are protected by a mutex.
Signed-off-by: Umang Jain <email at uajain.com>
---
src/android/camera_device.cpp | 15 +++
src/android/camera_device.h | 8 +-
src/android/camera_hal_manager.cpp | 153 ++++++++++++++++++++++++-----
src/android/camera_hal_manager.h | 15 ++-
4 files changed, 166 insertions(+), 25 deletions(-)
diff --git a/src/android/camera_device.cpp b/src/android/camera_device.cpp
index d918350..a79bb69 100644
--- a/src/android/camera_device.cpp
+++ b/src/android/camera_device.cpp
@@ -233,6 +233,21 @@ CameraDevice::~CameraDevice()
delete it.second;
}
+std::shared_ptr<CameraDevice> CameraDevice::create(unsigned int id,
+ const std::shared_ptr<Camera> &cam)
+{
+ struct Deleter : std::default_delete<CameraDevice> {
+ void operator()(CameraDevice *camera)
+ {
+ delete camera;
+ }
+ };
+
+ CameraDevice *camera = new CameraDevice(id, cam);
+
+ return std::shared_ptr<CameraDevice>(camera, Deleter());
+}
+
/*
* Initialize the camera static information.
* This method is called before the camera device is opened.
diff --git a/src/android/camera_device.h b/src/android/camera_device.h
index 7be9e11..7f9e010 100644
--- a/src/android/camera_device.h
+++ b/src/android/camera_device.h
@@ -47,8 +47,8 @@ struct CameraStream {
class CameraDevice : protected libcamera::Loggable
{
public:
- CameraDevice(unsigned int id, const std::shared_ptr<libcamera::Camera> &camera);
- ~CameraDevice();
+ static std::shared_ptr<CameraDevice> create(unsigned int id,
+ const std::shared_ptr<libcamera::Camera> &cam);
int initialize();
@@ -57,6 +57,7 @@ public:
unsigned int id() const { return id_; }
camera3_device_t *camera3Device() { return &camera3Device_; }
+ const libcamera::Camera *getCamera() { return camera_.get(); };
int facing() const { return facing_; }
int orientation() const { return orientation_; }
@@ -72,6 +73,9 @@ protected:
std::string logPrefix() const override;
private:
+ CameraDevice(unsigned int id, const std::shared_ptr<libcamera::Camera> &camera);
+ ~CameraDevice();
+
struct Camera3RequestDescriptor {
Camera3RequestDescriptor(unsigned int frameNumber,
unsigned int numBuffers);
diff --git a/src/android/camera_hal_manager.cpp b/src/android/camera_hal_manager.cpp
index 3d6d2b4..fdde2c0 100644
--- a/src/android/camera_hal_manager.cpp
+++ b/src/android/camera_hal_manager.cpp
@@ -8,6 +8,7 @@
#include "camera_hal_manager.h"
#include <libcamera/camera.h>
+#include <libcamera/property_ids.h>
#include "libcamera/internal/log.h"
@@ -35,6 +36,7 @@ CameraHalManager::CameraHalManager()
CameraHalManager::~CameraHalManager()
{
cameras_.clear();
+ camerasMap_.clear();
if (cameraManager_) {
cameraManager_->stop();
@@ -47,6 +49,13 @@ int CameraHalManager::init()
{
cameraManager_ = new CameraManager();
+ /* Support camera hotplug. */
+ cameraManager_->cameraAdded.connect(this, &CameraHalManager::cameraAdded);
+ cameraManager_->cameraRemoved.connect(this, &CameraHalManager::cameraRemoved);
+
+ cameraCounter_ = 0;
+ externalCameraCounter_ = 1000;
+
int ret = cameraManager_->start();
if (ret) {
LOG(HAL, Error) << "Failed to start camera manager: "
@@ -56,35 +65,25 @@ int CameraHalManager::init()
return ret;
}
- /*
- * For each Camera registered in the system, a CameraDevice
- * gets created here to wraps a libcamera Camera instance.
- *
- * \todo Support camera hotplug.
- */
- unsigned int index = 0;
- for (auto &cam : cameraManager_->cameras()) {
- CameraDevice *camera = new CameraDevice(index, cam);
- ret = camera->initialize();
- if (ret)
- continue;
-
- cameras_.emplace_back(camera);
- ++index;
- }
-
return 0;
}
CameraDevice *CameraHalManager::open(unsigned int id,
const hw_module_t *hardwareModule)
{
- if (id >= numCameras()) {
+ MutexLocker locker(mutex_);
+
+ auto iter = std::find_if(cameras_.begin(), cameras_.end(),
+ [id](std::shared_ptr<CameraDevice> &cam) {
+ return cam->id() == id;
+ });
+ if (iter == cameras_.end()) {
LOG(HAL, Error) << "Invalid camera id '" << id << "'";
return nullptr;
}
- CameraDevice *camera = cameras_[id].get();
+ CameraDevice *camera = iter->get();
+
if (camera->open(hardwareModule))
return nullptr;
@@ -93,9 +92,91 @@ CameraDevice *CameraHalManager::open(unsigned int id,
return camera;
}
+void CameraHalManager::cameraAdded(std::shared_ptr<Camera> cam)
+{
+ unsigned int id;
+ bool isCameraExternal = false;
+ bool isCameraNew = false;
+
+ MutexLocker locker(mutex_);
+
+ /* Each camera is assigned a unique integer id when it is seen for the
+ * first time. If the camera has been seen before, the id is reused and
+ * the camera is marked as CAMERA_DEVICE_STATUS_PRESENT subsequently.
+ *
+ * ID starts from '0' for internal cameras and '1000' for external cameras.
+ */
+ auto iter = camerasMap_.find(cam->id());
+ if (iter != camerasMap_.end()) {
+ id = iter->second;
+ } else {
+ isCameraNew = true;
+
+ /*
+ * Now check if this is an external camera and assign
+ * its id accordingly.
+ */
+ const ControlList &properties = cam->properties();
+ if (properties.contains(properties::Location) &&
+ properties.get(properties::Location) &
+ properties::CameraLocationExternal) {
+ isCameraExternal = true;
+ id = externalCameraCounter_;
+ } else {
+ id = cameraCounter_;
+ }
+ }
+
+ /*
+ * For each Camera registered in the system, a CameraDevice
+ * gets created here to wraps a libcamera Camera instance.
+ */
+ std::shared_ptr<CameraDevice> camera = CameraDevice::create(id, std::move(cam));
+ int ret = camera->initialize();
+ if (ret) {
+ LOG(HAL, Error) << "Failed to initialize camera: " << cam->id();
+ return;
+ }
+
+ if (isCameraNew) {
+ camerasMap_.emplace(cam->id(), id);
+
+ if (isCameraExternal)
+ externalCameraCounter_++;
+ else
+ cameraCounter_++;
+ }
+
+ cameras_.emplace_back(std::move(camera));
+
+ if (callbacks_)
+ callbacks_->camera_device_status_change(callbacks_, id,
+ CAMERA_DEVICE_STATUS_PRESENT);
+ LOG(HAL, Debug) << "Camera ID: " << id << " added successfully.";
+}
+
+void CameraHalManager::cameraRemoved(std::shared_ptr<Camera> cam)
+{
+ MutexLocker locker(mutex_);
+
+ auto iter = std::find_if(cameras_.begin(), cameras_.end(),
+ [cam](std::shared_ptr<CameraDevice> &camera) {
+ return cam.get() == camera->getCamera();
+ });
+ if (iter == cameras_.end())
+ return;
+
+ unsigned int id = (*iter)->id();
+ callbacks_->camera_device_status_change(callbacks_, id,
+ CAMERA_DEVICE_STATUS_NOT_PRESENT);
+ cameras_.erase(iter);
+
+ LOG(HAL, Debug) << "Camera ID: " << id << " removed successfully.";
+}
+
unsigned int CameraHalManager::numCameras() const
{
- return cameraManager_->cameras().size();
+ return cameraCounter_;
}
int CameraHalManager::getCameraInfo(unsigned int id, struct camera_info *info)
@@ -103,12 +184,18 @@ int CameraHalManager::getCameraInfo(unsigned int id, struct camera_info *info)
if (!info)
return -EINVAL;
- if (id >= numCameras()) {
+ MutexLocker locker(mutex_);
+
+ auto iter = std::find_if(cameras_.begin(), cameras_.end(),
+ [id](std::shared_ptr<CameraDevice> &cam) {
+ return cam->id() == id;
+ });
+ if (iter == cameras_.end()) {
LOG(HAL, Error) << "Invalid camera id '" << id << "'";
return -EINVAL;
}
- CameraDevice *camera = cameras_[id].get();
+ CameraDevice *camera = iter->get();
info->facing = camera->facing();
info->orientation = camera->orientation();
@@ -124,4 +211,26 @@ int CameraHalManager::getCameraInfo(unsigned int id, struct camera_info *info)
void CameraHalManager::setCallbacks(const camera_module_callbacks_t *callbacks)
{
callbacks_ = callbacks;
+
+ MutexLocker locker(mutex_);
+ /*
+ * Few cameras might have been hotplugged before setting callbacks_ here.
+ * We need to mark CAMERA_DEVICE_STATUS_PRESENT for them explicitly.
+ * This hold only for external cameras, as internal cameras are assumed to
+ * be present at module load time, by the framework.
+ */
+ for (auto &cam : cameraManager_->cameras()) {
+ auto iter = camerasMap_.find(cam->id());
+ if (iter == camerasMap_.end())
+ continue;
+
+ unsigned int id = iter->second;
+ const ControlList &properties = cam->properties();
+ if (properties.contains(properties::Location) &&
+ properties.get(properties::Location) &
+ properties::CameraLocationExternal) {
+ callbacks_->camera_device_status_change(callbacks_, id,
+ CAMERA_DEVICE_STATUS_PRESENT);
+ }
+ }
}
diff --git a/src/android/camera_hal_manager.h b/src/android/camera_hal_manager.h
index a582f04..7c481d4 100644
--- a/src/android/camera_hal_manager.h
+++ b/src/android/camera_hal_manager.h
@@ -7,6 +7,8 @@
#ifndef __ANDROID_CAMERA_MANAGER_H__
#define __ANDROID_CAMERA_MANAGER_H__
+#include <map>
+#include <mutex>
#include <stddef.h>
#include <vector>
@@ -18,6 +20,9 @@
class CameraDevice;
+using Mutex = std::mutex;
+using MutexLocker = std::unique_lock<std::mutex>;
+
class CameraHalManager
{
public:
@@ -33,10 +38,18 @@ public:
void setCallbacks(const camera_module_callbacks_t *callbacks);
private:
+ void cameraAdded(std::shared_ptr<libcamera::Camera> cam);
+ void cameraRemoved(std::shared_ptr<libcamera::Camera> cam);
+
libcamera::CameraManager *cameraManager_;
const camera_module_callbacks_t *callbacks_;
- std::vector<std::unique_ptr<CameraDevice>> cameras_;
+ std::vector<std::shared_ptr<CameraDevice>> cameras_;
+ std::map<std::string, unsigned int> camerasMap_;
+ Mutex mutex_;
+
+ unsigned int externalCameraCounter_;
+ unsigned int cameraCounter_;
};
#endif /* __ANDROID_CAMERA_MANAGER_H__ */
--
2.26.2
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