From patchwork Thu Feb 28 18:51:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Niklas_S=C3=B6derlund?= X-Patchwork-Id: 664 Return-Path: Received: from bin-mail-out-06.binero.net (bin-mail-out-06.binero.net [195.74.38.229]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id C4B50610B6 for ; Thu, 28 Feb 2019 19:51:37 +0100 (CET) X-Halon-ID: deeac7f1-3b89-11e9-8144-0050569116f7 Authorized-sender: niklas@soderlund.pp.se Received: from bismarck.berto.se (unknown [89.233.230.99]) by bin-vsp-out-03.atm.binero.net (Halon) with ESMTPA id deeac7f1-3b89-11e9-8144-0050569116f7; Thu, 28 Feb 2019 19:51:35 +0100 (CET) From: =?utf-8?q?Niklas_S=C3=B6derlund?= To: libcamera-devel@lists.libcamera.org Date: Thu, 28 Feb 2019 19:51:24 +0100 Message-Id: <20190228185126.32475-2-niklas.soderlund@ragnatech.se> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190228185126.32475-1-niklas.soderlund@ragnatech.se> References: <20190228185126.32475-1-niklas.soderlund@ragnatech.se> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v3 1/3] cam: fix order camera is operated on X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Feb 2019 18:51:38 -0000 Upcoming enforcing of order the camera shall be operate on is not compatible with the cam utility. Requests shall be queued after the camera is started, not before. Signed-off-by: Niklas Söderlund Reviewed-by: Laurent Pinchart --- src/cam/main.cpp | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/src/cam/main.cpp b/src/cam/main.cpp index 4c2df583fe8e99b7..8df8844c33a2d052 100644 --- a/src/cam/main.cpp +++ b/src/cam/main.cpp @@ -133,6 +133,7 @@ static int capture() int ret; std::vector streams = camera->streams(); + std::vector requests; ret = configureStreams(camera.get(), streams); if (ret < 0) { @@ -169,21 +170,24 @@ static int capture() goto out; } - ret = camera->queueRequest(request); - if (ret < 0) { - std::cerr << "Can't queue request" << std::endl; - goto out; - } + requests.push_back(request); } - std::cout << "Capture until user interrupts by SIGINT" << std::endl; - ret = camera->start(); if (ret) { std::cout << "Failed to start capture" << std::endl; goto out; } + for (Request *request : requests) { + ret = camera->queueRequest(request); + if (ret < 0) { + std::cerr << "Can't queue request" << std::endl; + goto out; + } + } + + std::cout << "Capture until user interrupts by SIGINT" << std::endl; ret = loop->exec(); ret = camera->stop(); From patchwork Thu Feb 28 18:51:25 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Niklas_S=C3=B6derlund?= X-Patchwork-Id: 666 Return-Path: Received: from bin-mail-out-05.binero.net (bin-mail-out-05.binero.net [195.74.38.228]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 82583610BB for ; Thu, 28 Feb 2019 19:51:39 +0100 (CET) X-Halon-ID: df50643b-3b89-11e9-8144-0050569116f7 Authorized-sender: niklas@soderlund.pp.se Received: from bismarck.berto.se (unknown [89.233.230.99]) by bin-vsp-out-03.atm.binero.net (Halon) with ESMTPA id df50643b-3b89-11e9-8144-0050569116f7; Thu, 28 Feb 2019 19:51:35 +0100 (CET) From: =?utf-8?q?Niklas_S=C3=B6derlund?= To: libcamera-devel@lists.libcamera.org Date: Thu, 28 Feb 2019 19:51:25 +0100 Message-Id: <20190228185126.32475-3-niklas.soderlund@ragnatech.se> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190228185126.32475-1-niklas.soderlund@ragnatech.se> References: <20190228185126.32475-1-niklas.soderlund@ragnatech.se> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v3 2/3] libcamera: store stream pointers in sets instead of a vectors X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Feb 2019 18:51:40 -0000 The arrays that store Stream pointers shall always contain unique values. Storing them in vectors opens up for the same stream pointer appearing twice. Remove this possibility by storing them in a set which guarantees each element is unique. Signed-off-by: Niklas Söderlund Reviewed-by: Jacopo Mondi Reviewed-by: Laurent Pinchart --- include/libcamera/camera.h | 11 ++++++----- src/cam/main.cpp | 10 +++++----- src/libcamera/camera.cpp | 8 ++++---- src/libcamera/include/pipeline_handler.h | 2 +- src/libcamera/pipeline/ipu3/ipu3.cpp | 6 +++--- src/libcamera/pipeline/uvcvideo.cpp | 6 +++--- src/libcamera/pipeline/vimc.cpp | 6 +++--- 7 files changed, 25 insertions(+), 24 deletions(-) diff --git a/include/libcamera/camera.h b/include/libcamera/camera.h index bf70255a6a5ea364..9c8ae01ed5c607f1 100644 --- a/include/libcamera/camera.h +++ b/include/libcamera/camera.h @@ -9,6 +9,7 @@ #include #include +#include #include #include @@ -27,7 +28,7 @@ class Camera final public: static std::shared_ptr create(PipelineHandler *pipe, const std::string &name, - const std::vector &streams); + const std::set &streams); Camera(const Camera &) = delete; Camera &operator=(const Camera &) = delete; @@ -40,9 +41,9 @@ public: int acquire(); void release(); - const std::vector &streams() const; + const std::set &streams() const; std::map - streamConfiguration(std::vector &streams); + streamConfiguration(std::set &streams); int configureStreams(std::map &config); int allocateBuffers(); @@ -64,8 +65,8 @@ private: std::shared_ptr pipe_; std::string name_; - std::vector streams_; - std::vector activeStreams_; + std::set streams_; + std::set activeStreams_; bool acquired_; bool disconnected_; diff --git a/src/cam/main.cpp b/src/cam/main.cpp index 8df8844c33a2d052..13aa35968f38964d 100644 --- a/src/cam/main.cpp +++ b/src/cam/main.cpp @@ -75,10 +75,10 @@ static int parseOptions(int argc, char *argv[]) return 0; } -static int configureStreams(Camera *camera, std::vector &streams) +static int configureStreams(Camera *camera, std::set &streams) { KeyValueParser::Options format = options[OptFormat]; - Stream *id = streams.front(); + Stream *id = *streams.begin(); std::map config = camera->streamConfiguration(streams); @@ -132,7 +132,7 @@ static int capture() { int ret; - std::vector streams = camera->streams(); + std::set streams = camera->streams(); std::vector requests; ret = configureStreams(camera.get(), streams); @@ -141,7 +141,7 @@ static int capture() return ret; } - Stream *stream = streams.front(); + Stream *stream = *streams.begin(); ret = camera->allocateBuffers(); if (ret) { @@ -237,7 +237,7 @@ int main(int argc, char **argv) goto out; } - const std::vector &streams = camera->streams(); + const std::set &streams = camera->streams(); if (streams.size() != 1) { std::cout << "Camera has " << streams.size() << " streams, only 1 is supported" diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp index 3789732b95d1ae38..84b97b5c2ce94ecf 100644 --- a/src/libcamera/camera.cpp +++ b/src/libcamera/camera.cpp @@ -66,7 +66,7 @@ LOG_DECLARE_CATEGORY(Camera) */ std::shared_ptr Camera::create(PipelineHandler *pipe, const std::string &name, - const std::vector &streams) + const std::set &streams) { struct Allocator : std::allocator { void construct(void *p, PipelineHandler *pipe, @@ -188,7 +188,7 @@ void Camera::release() * * \return An array of all the camera's streams. */ -const std::vector &Camera::streams() const +const std::set &Camera::streams() const { return streams_; } @@ -210,7 +210,7 @@ const std::vector &Camera::streams() const * empty list on error. */ std::map -Camera::streamConfiguration(std::vector &streams) +Camera::streamConfiguration(std::set &streams) { if (disconnected_ || !streams.size()) return std::map{}; @@ -264,7 +264,7 @@ int Camera::configureStreams(std::map &config) const StreamConfiguration &cfg = iter.second; stream->configuration_ = cfg; - activeStreams_.push_back(stream); + activeStreams_.insert(stream); /* * Allocate buffer objects in the pool. diff --git a/src/libcamera/include/pipeline_handler.h b/src/libcamera/include/pipeline_handler.h index 4363dcd8ed8ead97..4cd9b90c609c067e 100644 --- a/src/libcamera/include/pipeline_handler.h +++ b/src/libcamera/include/pipeline_handler.h @@ -45,7 +45,7 @@ public: virtual bool match(DeviceEnumerator *enumerator) = 0; virtual std::map - streamConfiguration(Camera *camera, std::vector &streams) = 0; + streamConfiguration(Camera *camera, std::set &streams) = 0; virtual int configureStreams(Camera *camera, std::map &config) = 0; diff --git a/src/libcamera/pipeline/ipu3/ipu3.cpp b/src/libcamera/pipeline/ipu3/ipu3.cpp index 9694d0ce51abda41..1066fbe350d934a0 100644 --- a/src/libcamera/pipeline/ipu3/ipu3.cpp +++ b/src/libcamera/pipeline/ipu3/ipu3.cpp @@ -32,7 +32,7 @@ public: std::map streamConfiguration(Camera *camera, - std::vector &streams) override; + std::set &streams) override; int configureStreams(Camera *camera, std::map &config) override; @@ -95,7 +95,7 @@ PipelineHandlerIPU3::~PipelineHandlerIPU3() std::map PipelineHandlerIPU3::streamConfiguration(Camera *camera, - std::vector &streams) + std::set &streams) { IPU3CameraData *data = cameraData(camera); std::map configs; @@ -374,7 +374,7 @@ void PipelineHandlerIPU3::registerCameras() std::unique_ptr data = utils::make_unique(); std::string cameraName = sensor->name() + " " + std::to_string(id); - std::vector streams{ &data->stream_ }; + std::set streams{ &data->stream_ }; std::shared_ptr camera = Camera::create(this, cameraName, streams); /* diff --git a/src/libcamera/pipeline/uvcvideo.cpp b/src/libcamera/pipeline/uvcvideo.cpp index b7b8ff109109e9c5..7b697c0685630d92 100644 --- a/src/libcamera/pipeline/uvcvideo.cpp +++ b/src/libcamera/pipeline/uvcvideo.cpp @@ -27,7 +27,7 @@ public: std::map streamConfiguration(Camera *camera, - std::vector &streams) override; + std::set &streams) override; int configureStreams(Camera *camera, std::map &config) override; @@ -63,7 +63,7 @@ PipelineHandlerUVC::~PipelineHandlerUVC() std::map PipelineHandlerUVC::streamConfiguration(Camera *camera, - std::vector &streams) + std::set &streams) { std::map configs; @@ -171,7 +171,7 @@ bool PipelineHandlerUVC::match(DeviceEnumerator *enumerator) return false; } - std::vector streams{ &stream_ }; + std::set streams{ &stream_ }; std::shared_ptr camera = Camera::create(this, media_->model(), streams); registerCamera(std::move(camera)); hotplugMediaDevice(media_.get()); diff --git a/src/libcamera/pipeline/vimc.cpp b/src/libcamera/pipeline/vimc.cpp index 812777cffbb3e618..9ba96323d335e010 100644 --- a/src/libcamera/pipeline/vimc.cpp +++ b/src/libcamera/pipeline/vimc.cpp @@ -27,7 +27,7 @@ public: std::map streamConfiguration(Camera *camera, - std::vector &streams) override; + std::set &streams) override; int configureStreams(Camera *camera, std::map &config) override; @@ -62,7 +62,7 @@ PipelineHandlerVimc::~PipelineHandlerVimc() std::map PipelineHandlerVimc::streamConfiguration(Camera *camera, - std::vector &streams) + std::set &streams) { std::map configs; @@ -171,7 +171,7 @@ bool PipelineHandlerVimc::match(DeviceEnumerator *enumerator) return false; } - std::vector streams{ &stream_ }; + std::set streams{ &stream_ }; std::shared_ptr camera = Camera::create(this, "VIMC Sensor B", streams); registerCamera(std::move(camera)); From patchwork Thu Feb 28 18:51:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Niklas_S=C3=B6derlund?= X-Patchwork-Id: 667 Return-Path: Received: from vsp-unauthed02.binero.net (vsp-unauthed02.binero.net [195.74.38.227]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 856BC610BB for ; Thu, 28 Feb 2019 19:51:40 +0100 (CET) X-Halon-ID: e01af104-3b89-11e9-8144-0050569116f7 Authorized-sender: niklas@soderlund.pp.se Received: from bismarck.berto.se (unknown [89.233.230.99]) by bin-vsp-out-03.atm.binero.net (Halon) with ESMTPA id e01af104-3b89-11e9-8144-0050569116f7; Thu, 28 Feb 2019 19:51:36 +0100 (CET) From: =?utf-8?q?Niklas_S=C3=B6derlund?= To: libcamera-devel@lists.libcamera.org Date: Thu, 28 Feb 2019 19:51:26 +0100 Message-Id: <20190228185126.32475-4-niklas.soderlund@ragnatech.se> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190228185126.32475-1-niklas.soderlund@ragnatech.se> References: <20190228185126.32475-1-niklas.soderlund@ragnatech.se> MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v3 3/3] libcamera: camera: add state machine to control access from applications X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Feb 2019 18:51:40 -0000 There is a need to better control the order of operations an application performs on a camera for it to function correctly. Add a basic state machine to ensure applications perform operations on the camera in good order. Internal to the Camera states are added; Available, Acquired, Configured, Prepared and Running. Each state represents a higher state of configuration of the camera ultimately leading to the highest state where the camera is capturing frames. Each state supports a subset of operations the application may perform. Signed-off-by: Niklas Söderlund Reviewed-by: Laurent Pinchart --- include/libcamera/camera.h | 18 ++- src/libcamera/camera.cpp | 266 +++++++++++++++++++++++++++++++------ 2 files changed, 238 insertions(+), 46 deletions(-) diff --git a/include/libcamera/camera.h b/include/libcamera/camera.h index 9c8ae01ed5c607f1..e5212cf05d221279 100644 --- a/include/libcamera/camera.h +++ b/include/libcamera/camera.h @@ -39,7 +39,7 @@ public: Signal disconnected; int acquire(); - void release(); + int release(); const std::set &streams() const; std::map @@ -47,7 +47,7 @@ public: int configureStreams(std::map &config); int allocateBuffers(); - void freeBuffers(); + int freeBuffers(); Request *createRequest(); int queueRequest(Request *request); @@ -56,20 +56,30 @@ public: int stop(); private: + enum State { + CameraAvailable, + CameraAcquired, + CameraConfigured, + CameraPrepared, + CameraRunning, + }; + Camera(PipelineHandler *pipe, const std::string &name); ~Camera(); + bool stateBetween(State low, State high) const; + bool stateIs(State state) const; + friend class PipelineHandler; void disconnect(); - int exclusiveAccess(); std::shared_ptr pipe_; std::string name_; std::set streams_; std::set activeStreams_; - bool acquired_; bool disconnected_; + State state_; }; } /* namespace libcamera */ diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp index 84b97b5c2ce94ecf..0b06c0d838b356f3 100644 --- a/src/libcamera/camera.cpp +++ b/src/libcamera/camera.cpp @@ -11,6 +11,7 @@ #include "log.h" #include "pipeline_handler.h" +#include "utils.h" /** * \file camera.h @@ -42,6 +43,9 @@ LOG_DECLARE_CATEGORY(Camera) * \class Camera * \brief Camera device * + * \todo Add documentation for camera start timings. What exactly does the + * camera expect the pipeline handler to do when start() is called? + * * The Camera class models a camera capable of producing one or more image * streams from a single image source. It provides the main interface to * configuring and controlling the device, and capturing image streams. It is @@ -52,6 +56,78 @@ LOG_DECLARE_CATEGORY(Camera) * created with the create() function which returns a shared pointer. The * Camera constructors and destructor are private, to prevent instances from * being constructed and destroyed manually. + * + * \section camera_operation Operating the Camera + * + * An application needs to perform a sequence of operations on a camera before + * it is ready to process requests. The camera needs to be acquired, configured + * and resources allocated or imported to prepare the camera for capture. Once + * started the camera can process requests until it is stopped. When an + * application is done with a camera all resources allocated needs to be freed + * and the camera released. + * + * An application may start and stop a camera multiple times as long as it is + * not released. The camera may also be reconfigured provided that all + * resources allocated are freed prior to the reconfiguration. + * + * \subsection Camera States + * + * To help manage the sequence of operations needed to control the camera a set + * of states are defined. Each state describes which operations may be performed + * on the camera. Operations not listed in the state diagram are allowed in all + * states. + * + * \dot + * digraph camera_state_machine { + * node [shape = doublecircle ]; Available; + * node [shape = circle ]; Acquired; + * node [shape = circle ]; Configured; + * node [shape = circle ]; Prepared; + * node [shape = circle ]; Running; + * + * Available -> Available [label = "release()"]; + * Available -> Acquired [label = "acquire()"]; + * + * Acquired -> Available [label = "release()"]; + * Acquired -> Configured [label = "configureStreams()"]; + * + * Configured -> Available [label = "release()"]; + * Configured -> Configured [label = "configureStreams()"]; + * Configured -> Prepared [label = "allocateBuffers()"]; + * + * Prepared -> Configured [label = "freeBuffers()"]; + * Prepared -> Prepared [label = "createRequest()"]; + * Prepared -> Running [label = "start()"]; + * + * Running -> Prepared [label = "stop()"]; + * Running -> Running [label = "createRequest(), queueRequest()"]; + * } + * \enddot + * + * \subsubsection Available + * The base state of a camera, an application can inspect the properties of the + * camera to determine if it wishes to use it. If an application wishes to use + * a camera it should acquire() it to proceed to the Acquired state. + * + * \subsubsection Acquired + * In the acquired state an application has exclusive access to the camera and + * may modify the camera's parameters to configure it and proceed to the + * Configured state. + * + * \subsubsection Configured + * The camera is configured and ready for the application to prepare it with + * resources. The camera may be reconfigured multiple times until resources + * are provided and the state progresses to Prepared. + * + * \subsubsection Prepared + * The camera has been configured and provided with resources and is ready to be + * started. The application may free the camera's resources to get back to the + * Configured state or start it to progress to the Running state. + * + * \subsubsection Running + * The camera is running and ready to process requests queued by the + * application. The camera remains in this state until it is stopped and moved + * to the Prepared state. */ /** @@ -116,17 +192,55 @@ const std::string &Camera::name() const */ Camera::Camera(PipelineHandler *pipe, const std::string &name) - : pipe_(pipe->shared_from_this()), name_(name), acquired_(false), - disconnected_(false) + : pipe_(pipe->shared_from_this()), name_(name), disconnected_(false), + state_(CameraAvailable) { } Camera::~Camera() { - if (acquired_) + if (!stateIs(CameraAvailable)) LOG(Camera, Error) << "Removing camera while still in use"; } +static const char *const camera_state_name[] = { + "Available", + "Acquired", + "Configured", + "Prepared", + "Running", +}; + +bool Camera::stateBetween(State low, State high) const +{ + if (state_ >= low && state_ <= high) + return true; + + ASSERT(static_cast(low) < ARRAY_SIZE(camera_state_name) && + static_cast(high) < ARRAY_SIZE(camera_state_name)); + + LOG(Camera, Debug) << "Camera in " << camera_state_name[state_] + << " state trying operation requiring state between " + << camera_state_name[low] << " and " + << camera_state_name[high]; + + return false; +} + +bool Camera::stateIs(State state) const +{ + if (state_ == state) + return true; + + ASSERT(static_cast(state) < ARRAY_SIZE(camera_state_name)); + + LOG(Camera, Debug) << "Camera in " << camera_state_name[state_] + << " state trying operation requiring state " + << camera_state_name[state]; + + return false; +} + /** * \brief Notify camera disconnection * @@ -135,11 +249,24 @@ Camera::~Camera() * instance notifies the application by emitting the #disconnected signal, and * ensures that all new calls to the application-facing Camera API return an * error immediately. + * + * \todo: Deal with pending requests if the camera is disconnected in a + * running state. + * \todo: Update comment about Running state when importing buffers as well as + * allocating them are supported. */ void Camera::disconnect() { LOG(Camera, Debug) << "Disconnecting camera " << name_; + /* + * If the camera was running when the hardware was removed force the + * state to Prepared to allow applications to call freeBuffers() and + * release() before deleting the camera. + */ + if (state_ == CameraRunning) + state_ = CameraPrepared; + disconnected_ = true; disconnected.emit(this); } @@ -155,16 +282,24 @@ void Camera::disconnect() * Once exclusive access isn't needed anymore, the device should be released * with a call to the release() function. * + * This function effects the state of the camera, see \ref camera_operation. + * * \todo Implement exclusive access across processes. * * \return 0 on success or a negative error code otherwise + * \retval -ENODEV The camera has been disconnected from the system + * \retval -EBUSY The camera is not free and can't be acquired by the caller */ int Camera::acquire() { - if (acquired_) + if (disconnected_) + return -ENODEV; + + if (!stateIs(CameraAvailable)) return -EBUSY; - acquired_ = true; + state_ = CameraAcquired; + return 0; } @@ -173,10 +308,20 @@ int Camera::acquire() * * Releasing the camera device allows other users to acquire exclusive access * with the acquire() function. + * + * This function effects the state of the camera, see \ref camera_operation. + * + * \return 0 on success or a negative error code otherwise + * \retval -EBUSY The camera is running and can't be released */ -void Camera::release() +int Camera::release() { - acquired_ = false; + if (!stateBetween(CameraAvailable, CameraConfigured)) + return -EBUSY; + + state_ = CameraAvailable; + + return 0; } /** @@ -235,18 +380,22 @@ Camera::streamConfiguration(std::set &streams) * Exclusive access to the camera shall be ensured by a call to acquire() prior * to calling this function, otherwise an -EACCES error will be returned. * + * This function effects the state of the camera, see \ref camera_operation. + * * \return 0 on success or a negative error code otherwise - * \retval -ENODEV The camera is not connected to any hardware - * \retval -EACCES The user has not acquired exclusive access to the camera + * \retval -ENODEV The camera has been disconnected from the system + * \retval -EACCES The camera is not in a state where it can be configured * \retval -EINVAL The configuration is not valid */ int Camera::configureStreams(std::map &config) { int ret; - ret = exclusiveAccess(); - if (ret) - return ret; + if (disconnected_) + return -ENODEV; + + if (!stateBetween(CameraAvailable, CameraConfigured)) + return -EACCES; if (!config.size()) { LOG(Camera, Error) @@ -273,20 +422,28 @@ int Camera::configureStreams(std::map &config) stream->bufferPool().createBuffers(cfg.bufferCount); } + state_ = CameraConfigured; + return 0; } /** * \brief Allocate buffers for all configured streams + * + * This function effects the state of the camera, see \ref camera_operation. + * * \return 0 on success or a negative error code otherwise + * \retval -ENODEV The camera has been disconnected from the system + * \retval -EACCES The camera is not in a state where buffers can be allocated + * \retval -EINVAL The configuration is not valid */ int Camera::allocateBuffers() { - int ret; + if (disconnected_) + return -ENODEV; - ret = exclusiveAccess(); - if (ret) - return ret; + if (!stateIs(CameraConfigured)) + return -EACCES; if (activeStreams_.empty()) { LOG(Camera, Error) @@ -295,7 +452,7 @@ int Camera::allocateBuffers() } for (Stream *stream : activeStreams_) { - ret = pipe_->allocateBuffers(this, stream); + int ret = pipe_->allocateBuffers(this, stream); if (ret) { LOG(Camera, Error) << "Failed to allocate buffers"; freeBuffers(); @@ -303,14 +460,24 @@ int Camera::allocateBuffers() } } + state_ = CameraPrepared; + return 0; } /** * \brief Release all buffers from allocated pools in each stream + * + * This function effects the state of the camera, see \ref camera_operation. + * + * \return 0 on success or a negative error code otherwise + * \retval -EACCES The camera is not in a state where buffers can be freed */ -void Camera::freeBuffers() +int Camera::freeBuffers() { + if (!stateIs(CameraPrepared)) + return -EACCES; + for (Stream *stream : activeStreams_) { if (!stream->bufferPool().count()) continue; @@ -318,6 +485,10 @@ void Camera::freeBuffers() pipe_->freeBuffers(this, stream); stream->bufferPool().destroyBuffers(); } + + state_ = CameraConfigured; + + return 0; } /** @@ -333,7 +504,7 @@ void Camera::freeBuffers() */ Request *Camera::createRequest() { - if (exclusiveAccess()) + if (disconnected_ || !stateBetween(CameraPrepared, CameraRunning)) return nullptr; return new Request(this); @@ -351,16 +522,18 @@ Request *Camera::createRequest() * automatically after it completes. * * \return 0 on success or a negative error code otherwise + * \retval -ENODEV The camera has been disconnected from the system + * \retval -EACCES The camera is not running so requests can't be queued */ int Camera::queueRequest(Request *request) { - int ret; + if (disconnected_) + return -ENODEV; - ret = exclusiveAccess(); - if (ret) - return ret; + if (!stateIs(CameraRunning)) + return -EACCES; - ret = request->prepare(); + int ret = request->prepare(); if (ret) { LOG(Camera, Error) << "Failed to prepare request"; return ret; @@ -376,17 +549,29 @@ int Camera::queueRequest(Request *request) * can queue requests to the camera to process and return to the application * until the capture session is terminated with \a stop(). * + * This function effects the state of the camera, see \ref camera_operation. + * * \return 0 on success or a negative error code otherwise + * \retval -ENODEV The camera has been disconnected from the system + * \retval -EACCES The camera is not in a state where it can be started */ int Camera::start() { - int ret = exclusiveAccess(); - if (ret) - return ret; + if (disconnected_) + return -ENODEV; + + if (!stateIs(CameraPrepared)) + return -EACCES; LOG(Camera, Debug) << "Starting capture"; - return pipe_->start(this); + int ret = pipe_->start(this); + if (ret) + return ret; + + state_ = CameraRunning; + + return 0; } /** @@ -395,30 +580,27 @@ int Camera::start() * This method stops capturing and processing requests immediately. All pending * requests are cancelled and complete synchronously in an error state. * + * This function effects the state of the camera, see \ref camera_operation. + * * \return 0 on success or a negative error code otherwise + * \retval -ENODEV The camera has been disconnected from the system + * \retval -EACCES The camera is not running so can't be stopped */ int Camera::stop() { - int ret = exclusiveAccess(); - if (ret) - return ret; + if (disconnected_) + return -ENODEV; + + if (!stateIs(CameraRunning)) + return -EACCES; LOG(Camera, Debug) << "Stopping capture"; + state_ = CameraPrepared; + pipe_->stop(this); return 0; } -int Camera::exclusiveAccess() -{ - if (disconnected_) - return -ENODEV; - - if (!acquired_) - return -EACCES; - - return 0; -} - } /* namespace libcamera */