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AgeCommit message (Collapse)Author
2021-05-25android: Add CameraHalConfig classJacopo Mondi
Add a CameraHalConfig class to the Android Camera3 HAL layer. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
2021-05-25libcamera: List dependency for Android Camera3 HALJacopo Mondi
Add to the README.rst file the list of depdendencies for the Android Camera3 HAL. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
2021-04-05Add alternative meson install commandVedant Paranjape
While installing meson using pip3 install --user meson, due to python path issues, build.ninja can't be located by ninja. meson generates ninja files fine, but then when you run ninja, it is unable to find meson's build.ninja python module due to path issues. It gives the following error on ninja -C build install: ninja: Entering directory `build' ninja: error: loading 'build.ninja': No such file or directory After uninstalling meson using pip3 and installing it again using pip without --user argument solved the issue. Add a troubleshooting section to the readme to describe this issue and suggest possible solutions. Signed-off-by: Vedant Paranjape <vedantparanjape160201@gmail.com> Reviewed-by: Paul Elder <paul.elder@ideasonboard.com> Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
2021-03-19Documentation: Fix typos and wrong rST syntax for literalsNícolas F. R. A. Prado
Fix some typos and some literals using ` instead of ``. Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Reviewed-by: Sebastian Fricke <sebastian.fricke@posteo.net> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2021-03-08README: Update tracing dependenciesKieran Bingham
The packages required for tracing libcamera projects were incorrectly specified. Update with the correct prefix for the dev package on liblttng-ust-dev and also provide the lttng-tools package which provides the utilities required to handle tracing. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Paul Elder <paul.elder@ideasonboard.com> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2021-02-04subprojects: Add libyuv and built if -Dandroid=enabledHirokazu Honda
Android HAL adaptation layer may need image processing, for example, scaling and format conversion. Libyuv is a general image processing. This adds libyuv to subprojects, so that it is forked locally and can be used with Android HAL implementation code. Signed-off-by: Hirokazu Honda <hiroh@chromium.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-11-15cam: Use libevent to implement event loopLaurent Pinchart
To prepare for removal of the EventDispatcher from the libcamera public API, switch to libevent to handle the event loop. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2020-11-11README, meson: Add dependency on ply and jinja2 for IPA interface generationPaul Elder
Specify in the readme and meson file that we depend on python3-ply and python3-jinja2 for generating the IPA interface. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-11-03libcamera: tracing: Implement tracing infrastructurePaul Elder
Implement tracing infrastructure in libcamera. It takes .tp files, as required by lttng, and generates a tracepoint header and C file, as lttng requires. meson is updated accordingly to get it to compile with the rest of libcamera. Update the documentation accordingly. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-09-24meson: Bump meson version to 0.51Ricardo Ribalda
Version 0.51 allows, among others, checking for python modules, which is a required feature. It is also now easily accessible: it is in stable distros such as Debian testing, or in pip: https://tracker.debian.org/pkg/meson https://pypi.org/project/meson/ Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Ricardo Ribalda <ricardo@ribalda.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-09-24README: Add missing dependency for documentationRicardo Ribalda
Doxygen fails to create the documentation with this message: [145/276] Generating doxygen with a custom command sh: 1: dot: not found error: Problems running dot: exit code=127, command='dot', arguments='"/home/user/libcamera/build/Documentation/api-html/inline_dotgraph_1.dot" -Tpng -o "/home/user/libcamera/build/Documentation/api-html/dot_inline_dotgraph_1.png"' sh: 1: dot: not found error: Problems running dot: exit code=127, command='dot', arguments='"/home/user/libcamera/build/Documentation/api-html/inline_dotgraph_1.dot" -Tcmapx -o "/home/user/libcamera/build/Documentation/api-html/dot_inline_dotgraph_1.map"' [276/276] Linking target test/utils Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Signed-off-by: Ricardo Ribalda <ricardo@ribalda.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-09-24README: Add missing libtiff-dev package for qcamRicardo Ribalda
Without it: Run-time dependency libtiff-4 found: NO (tried pkgconfig and cmake) Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Signed-off-by: Ricardo Ribalda <ricardo@ribalda.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-09-24README: Add missing package for Qt5 toolsRicardo Ribalda
Without it: Program /usr/lib/x86_64-linux-gnu/qt5/bin/lrelease found: NO Program lrelease-qt5 found: NO Program lrelease found: NO found but need: '== 5.14.2' Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Signed-off-by: Ricardo Ribalda <ricardo@ribalda.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-09-24README: Move pkg-config to Meson sectionRicardo Ribalda
pkg-config it is not only used to detect libudev-dev, it is used for detecting gstreamer and others. So it is more correct to place it on the Meson Build system section. Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Signed-off-by: Ricardo Ribalda <ricardo@ribalda.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-09-24README: Add libboost to list of dependenciesRicardo Ribalda
Raspberry Pi IPA, which is enabled by default, requires libboost to compile. Specify in the documentation its dependencies and how to disable the IPA. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Ricardo Ribalda <ricardo@ribalda.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-09-24README: Move the required dependencies to the topRicardo Ribalda
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Signed-off-by: Ricardo Ribalda <ricardo@ribalda.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-09-24README: Unify dependency namesRicardo Ribalda
All the dependencies are for libcamera, so we should move all the packages under this paragraph, or make a paragraph for Meson, and a second one for python3-yaml. I think the later is more clear. Signed-off-by: Ricardo Ribalda <ricardo@ribalda.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-04-16libcamera: Make IPA module signing mandatory for the meantimeLaurent Pinchart
IPA module signing is optional, but when not available due to missing dependencies, we hit failures due to a non fully implemented IPA isolation. Make module signing mandatory until isolation is functional. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-04-16libcamera: Document dependencies for IPA module signingLaurent Pinchart
Document the dependency on libgnutls28-dev and openssl for IPA module signing int he README.rst file. While at it, sort the entries alphabetically. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-04-15licenses: Add SPDX headers to RST documentationLaurent Pinchart
The documentation files are licensed under CC-BY-SA-4.0, but this has never been specified explicitly. Add corresponding SPDX headers. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-03-07gst: Document dependencies and quick usageNicolas Dufresne
This is a quick startup guide allowing to build and use the GStreamer element from the libcamera source tree. Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-01-17README: Remove duplicated lineLaurent Pinchart
The commit 2de78434ca71 ("meson: Bump required version to 0.47") included an extra duplicated line (my bad, the issue happened when applying). Fix it. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-01-17meson: Bump required version to 0.47Nicolas Dufresne
This is needed to use option type 'feature'. This is a tri-state (auto/enabled/disabled) which comes with utility to enable them all, or disabled them all to avoid any dynamic selection happening. It can also be used as value to any "required" field. This will be used in GStreamer support. If you don't have a recent enough meson in your distribution, you can always install or upgrade your version using pip3. pip3 install --user meson pip3 install --user --upgrade meson Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com> Reviewed: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-11-18README: Simplify a bit the build instructionsEzequiel Garcia
Less typing for the same result. Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-10-24Documentation: Add git clone information to Getting StartedLaurent Pinchart
As the Getting Started section is displayed on the website, it should contain commands related to cloning the repository. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-10-23Documentation: Hide the Getting Started informationLaurent Pinchart
The Getting Started information makes little sense on the generated documentation, as a developer with documentation compiled from a local libcamera source tree has already got started. We however want to keep the information in the top-level README.rst as it is useful there. In order to hide the Getting Started information from the front page while keeping it in README.rst, add comments to delimitate sections of README.rst, and include only a subset of the file in the front page. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-10-05libcamera: controls: Auto-generate control_ids.h and control_ids.cppLaurent Pinchart
Bring back auto-generation of control ids. In this version, both the header and the source files are generated from a single YAML file that stores all control definitions. This allows centralising controls in a single file, while the previous version required keeping both declarations (in a header) and documentation (in a the source) in sync manually. Using YAML as a format to store control definitions is a trade-off between ease of use (there are many YAML parsers available) and simplicity (XML was considered, but would have lead to more complex processing). A new build time dependency is added on python3-yaml, which should be available as a package in all distributions and build environments. The YAML format is likely to change over time as we improve documentation of controls, the first version simply copies the information currently available. Future improvements should also include a YAML schema to validate the YAML source file. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-08-16readme: Provide build requirementsKieran Bingham
Provide an initial list of build dependancies for Debian based systems. Other distributions will be added separately. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-08-16readme: Move index page content to READMEKieran Bingham
Move the introduction content from the index.rst to the README.rst so that it can also be found quickly from the top level. Include the README.rst directly into the index.rst to continue serving it as the front page material. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-08-16readme: Convert from Markdown to RSTKieran Bingham
The Documentation and top-level README both serve to provide information to new developers and users of libcamera. Currently our README.md is sparse, and should be expanded with more useful information such as build requirements as well as compilation directions. Any information provided in the README also serves a purpose in the main documentation and website and could be a cause of duplicated content. To allow direct integration of the top level README document into our sphinx documentation (and thus the libcamera.org website) convert the README.md into ReSTructured text format. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
generated by cgit v1.2.1 (git 2.18.0) at 2024-07-11 13:54:03 +0000
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/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2018, Google Inc.
 *
 * camera.cpp - Camera device
 */

#include <libcamera/camera.h>

#include <atomic>
#include <iomanip>

#include <libcamera/framebuffer_allocator.h>
#include <libcamera/request.h>
#include <libcamera/stream.h>

#include "libcamera/internal/log.h"
#include "libcamera/internal/pipeline_handler.h"
#include "libcamera/internal/utils.h"

/**
 * \file camera.h
 * \brief Camera device handling
 *
 * At the core of libcamera is the camera device, combining one image source
 * with processing hardware able to provide one or multiple image streams. The
 * Camera class represents a camera device.
 *
 * A camera device contains a single image source, and separate camera device
 * instances relate to different image sources. For instance, a phone containing
 * front and back image sensors will be modelled with two camera devices, one
 * for each sensor. When multiple streams can be produced from the same image
 * source, all those streams are guaranteed to be part of the same camera
 * device.
 *
 * While not sharing image sources, separate camera devices can share other
 * system resources, such as an ISP. For this reason camera device instances may
 * not be fully independent, in which case usage restrictions may apply. For
 * instance, a phone with a front and a back camera device may not allow usage
 * of the two devices simultaneously.
 */

namespace libcamera {

LOG_DECLARE_CATEGORY(Camera)

/**
 * \class CameraConfiguration
 * \brief Hold configuration for streams of the camera

 * The CameraConfiguration holds an ordered list of stream configurations. It
 * supports iterators and operates as a vector of StreamConfiguration instances.
 * The stream configurations are inserted by addConfiguration(), and the
 * operator[](int) returns a reference to the StreamConfiguration based on its
 * insertion index. Accessing a stream configuration with an invalid index
 * results in undefined behaviour.
 *
 * CameraConfiguration instances are retrieved from the camera with
 * Camera::generateConfiguration(). Applications may then inspect the
 * configuration, modify it, and possibly add new stream configuration entries
 * with addConfiguration(). Once the camera configuration satisfies the
 * application, it shall be validated by a call to validate(). The validation
 * implements "try" semantics: it adjusts invalid configurations to the closest
 * achievable parameters instead of rejecting them completely. Applications
 * then decide whether to accept the modified configuration, or try again with
 * a different set of parameters. Once the configuration is valid, it is passed
 * to Camera::configure().
 */

/**
 * \enum CameraConfiguration::Status
 * \brief Validity of a camera configuration
 * \var CameraConfiguration::Valid
 * The configuration is fully valid
 * \var CameraConfiguration::Adjusted
 * The configuration has been adjusted to a valid configuration
 * \var CameraConfiguration::Invalid
 * The configuration is invalid and can't be adjusted automatically
 */

/**
 * \typedef CameraConfiguration::iterator
 * \brief Iterator for the stream configurations in the camera configuration
 */

/**
 * \typedef CameraConfiguration::const_iterator
 * \brief Const iterator for the stream configuration in the camera
 * configuration
 */

/**
 * \brief Create an empty camera configuration
 */
CameraConfiguration::CameraConfiguration()
	: config_({})
{
}

CameraConfiguration::~CameraConfiguration()
{
}

/**
 * \brief Add a stream configuration to the camera configuration
 * \param[in] cfg The stream configuration
 */
void CameraConfiguration::addConfiguration(const StreamConfiguration &cfg)
{
	config_.push_back(cfg);
}

/**
 * \fn CameraConfiguration::validate()
 * \brief Validate and possibly adjust the camera configuration
 *
 * This method adjusts the camera configuration to the closest valid
 * configuration and returns the validation status.
 *
 * \todo: Define exactly when to return each status code. Should stream
 * parameters set to 0 by the caller be adjusted without returning Adjusted ?
 * This would potentially be useful for applications but would get in the way
 * in Camera::configure(). Do we need an extra status code to signal this ?
 *
 * \todo: Handle validation of buffers count when refactoring the buffers API.
 *
 * \return A CameraConfiguration::Status value that describes the validation
 * status.
 * \retval CameraConfiguration::Invalid The configuration is invalid and can't
 * be adjusted. This may only occur in extreme cases such as when the
 * configuration is empty.
 * \retval CameraConfigutation::Adjusted The configuration has been adjusted
 * and is now valid. Parameters may have changed for any stream, and stream
 * configurations may have been removed. The caller shall check the
 * configuration carefully.
 * \retval CameraConfiguration::Valid The configuration was already valid and
 * hasn't been adjusted.
 */

/**
 * \brief Retrieve a reference to a stream configuration
 * \param[in] index Numerical index
 *
 * The \a index represents the zero based insertion order of stream
 * configuration into the camera configuration with addConfiguration(). Calling
 * this method with an invalid index results in undefined behaviour.
 *
 * \return The stream configuration
 */
StreamConfiguration &CameraConfiguration::at(unsigned int index)
{
	return config_[index];
}

/**
 * \brief Retrieve a const reference to a stream configuration
 * \param[in] index Numerical index
 *
 * The \a index represents the zero based insertion order of stream
 * configuration into the camera configuration with addConfiguration(). Calling
 * this method with an invalid index results in undefined behaviour.
 *
 * \return The stream configuration
 */
const StreamConfiguration &CameraConfiguration::at(unsigned int index) const
{
	return config_[index];
}

/**
 * \fn StreamConfiguration &CameraConfiguration::operator[](unsigned int)
 * \brief Retrieve a reference to a stream configuration
 * \param[in] index Numerical index
 *
 * The \a index represents the zero based insertion order of stream
 * configuration into the camera configuration with addConfiguration(). Calling
 * this method with an invalid index results in undefined behaviour.
 *
 * \return The stream configuration
 */

/**
 * \fn const StreamConfiguration &CameraConfiguration::operator[](unsigned int) const
 * \brief Retrieve a const reference to a stream configuration
 * \param[in] index Numerical index
 *
 * The \a index represents the zero based insertion order of stream
 * configuration into the camera configuration with addConfiguration(). Calling
 * this method with an invalid index results in undefined behaviour.
 *
 * \return The stream configuration
 */

/**
 * \brief Retrieve an iterator to the first stream configuration in the
 * sequence
 * \return An iterator to the first stream configuration
 */
CameraConfiguration::iterator CameraConfiguration::begin()
{
	return config_.begin();
}

/**
 * \brief Retrieve a const iterator to the first element of the stream
 * configurations
 * \return A const iterator to the first stream configuration
 */
CameraConfiguration::const_iterator CameraConfiguration::begin() const
{
	return config_.begin();
}

/**
 * \brief Retrieve an iterator pointing to the past-the-end stream
 * configuration in the sequence
 * \return An iterator to the element following the last stream configuration
 */
CameraConfiguration::iterator CameraConfiguration::end()
{
	return config_.end();
}

/**
 * \brief Retrieve a const iterator pointing to the past-the-end stream
 * configuration in the sequence
 * \return A const iterator to the element following the last stream
 * configuration
 */
CameraConfiguration::const_iterator CameraConfiguration::end() const
{
	return config_.end();
}

/**
 * \brief Check if the camera configuration is empty
 * \return True if the configuration is empty
 */
bool CameraConfiguration::empty() const
{
	return config_.empty();
}

/**
 * \brief Retrieve the number of stream configurations
 * \return Number of stream configurations
 */
std::size_t CameraConfiguration::size() const
{
	return config_.size();
}

/**
 * \var CameraConfiguration::config_
 * \brief The vector of stream configurations
 */

class Camera::Private
{
public:
	enum State {
		CameraAvailable,
		CameraAcquired,
		CameraConfigured,
		CameraRunning,
	};

	Private(PipelineHandler *pipe, const std::string &name,
		const std::set<Stream *> &streams);
	~Private();

	int isAccessAllowed(State state, bool allowDisconnected = false) const;
	int isAccessAllowed(State low, State high,
			    bool allowDisconnected = false) const;

	void disconnect();
	void setState(State state);

	std::shared_ptr<PipelineHandler> pipe_;
	std::string name_;
	std::set<Stream *> streams_;
	std::set<Stream *> activeStreams_;

private:
	bool disconnected_;
	std::atomic<State> state_;
};

Camera::Private::Private(PipelineHandler *pipe, const std::string &name,
			 const std::set<Stream *> &streams)
	: pipe_(pipe->shared_from_this()), name_(name), streams_(streams),
	  disconnected_(false), state_(CameraAvailable)
{
}

Camera::Private::~Private()
{
	if (state_.load(std::memory_order_acquire) != Private::CameraAvailable)
		LOG(Camera, Error) << "Removing camera while still in use";
}

static const char *const camera_state_names[] = {
	"Available",
	"Acquired",
	"Configured",
	"Running",
};

int Camera::Private::isAccessAllowed(State state, bool allowDisconnected) const
{
	if (!allowDisconnected && disconnected_)
		return -ENODEV;

	State currentState = state_.load(std::memory_order_acquire);
	if (currentState == state)
		return 0;

	ASSERT(static_cast<unsigned int>(state) < ARRAY_SIZE(camera_state_names));

	LOG(Camera, Debug) << "Camera in " << camera_state_names[currentState]
			   << " state trying operation requiring state "
			   << camera_state_names[state];

	return -EACCES;
}

int Camera::Private::isAccessAllowed(State low, State high,
				     bool allowDisconnected) const
{
	if (!allowDisconnected && disconnected_)
		return -ENODEV;

	State currentState = state_.load(std::memory_order_acquire);
	if (currentState >= low && currentState <= high)
		return 0;

	ASSERT(static_cast<unsigned int>(low) < ARRAY_SIZE(camera_state_names) &&
	       static_cast<unsigned int>(high) < ARRAY_SIZE(camera_state_names));

	LOG(Camera, Debug) << "Camera in " << camera_state_names[currentState]
			   << " state trying operation requiring state between "
			   << camera_state_names[low] << " and "
			   << camera_state_names[high];

	return -EACCES;
}

void Camera::Private::disconnect()
{
	/*
	 * If the camera was running when the hardware was removed force the
	 * state to Configured state to allow applications to free resources
	 * and call release() before deleting the camera.
	 */
	if (state_.load(std::memory_order_acquire) == Private::CameraRunning)
		state_.store(Private::CameraConfigured, std::memory_order_release);

	disconnected_ = true;
}

void Camera::Private::setState(State state)
{
	state_.store(state, std::memory_order_release);
}

/**
 * \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
 * the central object exposed by libcamera.
 *
 * To support the central nature of Camera objects, libcamera manages the
 * lifetime of camera instances with std::shared_ptr<>. Instances shall be
 * 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 and
 * configured 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, the camera needs to be released.
 *
 * An application may start and stop a camera multiple times as long as it is
 * not released. The camera may also be reconfigured.
 *
 * Functions that affect the camera state as defined below are generally not
 * synchronized with each other by the Camera class. The caller is responsible
 * for ensuring their synchronization if necessary.
 *
 * \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. Performing an operation not allowed in the camera state
 * results in undefined behaviour. Operations not listed at all 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 ]; Running;
 *
 *   Available -> Available [label = "release()"];
 *   Available -> Acquired [label = "acquire()"];
 *
 *   Acquired -> Available [label = "release()"];
 *   Acquired -> Configured [label = "configure()"];
 *
 *   Configured -> Available [label = "release()"];
 *   Configured -> Configured [label = "configure(), createRequest()"];
 *   Configured -> Running [label = "start()"];
 *
 *   Running -> Configured [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 to be started. The application may
 * release() the camera and to get back to the Available 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 Configured state.
 */

/**
 * \brief Create a camera instance
 * \param[in] pipe The pipeline handler responsible for the camera device
 * \param[in] name The name of the camera device
 * \param[in] streams Array of streams the camera provides
 *
 * The caller is responsible for guaranteeing unicity of the camera name.
 *
 * \return A shared pointer to the newly created camera object
 */
std::shared_ptr<Camera> Camera::create(PipelineHandler *pipe,
				       const std::string &name,
				       const std::set<Stream *> &streams)
{
	struct Deleter : std::default_delete<Camera> {
		void operator()(Camera *camera)
		{
			camera->deleteLater();
		}
	};

	Camera *camera = new Camera(pipe, name, streams);

	return std::shared_ptr<Camera>(camera, Deleter());
}

/**
 * \brief Retrieve the name of the camera
 * \context This function is \threadsafe.
 * \return Name of the camera device
 */
const std::string &Camera::name() const
{
	return p_->name_;
}

/**
 * \var Camera::bufferCompleted
 * \brief Signal emitted when a buffer for a request queued to the camera has
 * completed
 */

/**
 * \var Camera::requestCompleted
 * \brief Signal emitted when a request queued to the camera has completed
 */

/**
 * \var Camera::disconnected
 * \brief Signal emitted when the camera is disconnected from the system
 *
 * This signal is emitted when libcamera detects that the camera has been
 * removed from the system. For hot-pluggable devices this is usually caused by
 * physical device disconnection. The media device is passed as a parameter.
 *
 * As soon as this signal is emitted the camera instance will refuse all new
 * application API calls by returning errors immediately.
 */

Camera::Camera(PipelineHandler *pipe, const std::string &name,
	       const std::set<Stream *> &streams)
	: p_(new Private(pipe, name, streams))
{
}

Camera::~Camera()
{
}

/**
 * \brief Notify camera disconnection
 *
 * This method is used to notify the camera instance that the underlying
 * hardware has been unplugged. In response to the disconnection the 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.
 */
void Camera::disconnect()
{
	LOG(Camera, Debug) << "Disconnecting camera " << name();

	p_->disconnect();
	disconnected.emit(this);
}

int Camera::exportFrameBuffers(Stream *stream,
			       std::vector<std::unique_ptr<FrameBuffer>> *buffers)
{
	int ret = p_->isAccessAllowed(Private::CameraConfigured);
	if (ret < 0)
		return ret;

	if (streams().find(stream) == streams().end())
		return -EINVAL;

	if (p_->activeStreams_.find(stream) == p_->activeStreams_.end())
		return -EINVAL;

	return p_->pipe_->invokeMethod(&PipelineHandler::exportFrameBuffers,
				       ConnectionTypeBlocking, this, stream,
				       buffers);
}

/**
 * \brief Acquire the camera device for exclusive access
 *
 * After opening the device with open(), exclusive access must be obtained
 * before performing operations that change the device state. This function is
 * not blocking, if the device has already been acquired (by the same or another
 * process) the -EBUSY error code is returned.
 *
 * Acquiring a camera will limit usage of any other camera(s) provided by the
 * same pipeline handler to the same instance of libcamera. The limit is in
 * effect until all cameras from the pipeline handler are released. Other
 * instances of libcamera can still list and examine the cameras but will fail
 * if they attempt to acquire() any of them.
 *
 * Once exclusive access isn't needed anymore, the device should be released
 * with a call to the release() function.
 *
 * \context This function is \threadsafe. It may only be called when the camera
 * is in the Available state as defined in \ref camera_operation.
 *
 * \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()
{
	/*
	 * No manual locking is required as PipelineHandler::lock() is
	 * thread-safe.
	 */
	int ret = p_->isAccessAllowed(Private::CameraAvailable);
	if (ret < 0)
		return ret == -EACCES ? -EBUSY : ret;

	if (!p_->pipe_->lock()) {
		LOG(Camera, Info)
			<< "Pipeline handler in use by another process";
		return -EBUSY;
	}

	p_->setState(Private::CameraAcquired);

	return 0;
}

/**
 * \brief Release exclusive access to the camera device
 *
 * Releasing the camera device allows other users to acquire exclusive access
 * with the acquire() function.
 *
 * \context This function may only be called when the camera is in the
 * Available or Configured state as defined in \ref camera_operation, and shall
 * be synchronized by the caller with other functions that affect the camera
 * state.
 *
 * \return 0 on success or a negative error code otherwise
 * \retval -EBUSY The camera is running and can't be released
 */
int Camera::release()
{
	int ret = p_->isAccessAllowed(Private::CameraAvailable,
				      Private::CameraConfigured, true);
	if (ret < 0)
		return ret == -EACCES ? -EBUSY : ret;

	p_->pipe_->unlock();

	p_->setState(Private::CameraAvailable);

	return 0;
}

/**
 * \brief Retrieve the list of controls supported by the camera
 *
 * The list of controls supported by the camera and their associated
 * constraints remain constant through the lifetime of the Camera object.
 *
 * \context This function is \threadsafe.
 *
 * \return A ControlInfoMap listing the controls supported by the camera
 */
const ControlInfoMap &Camera::controls()
{
	return p_->pipe_->controls(this);
}

/**
 * \brief Retrieve the list of properties of the camera
 *
 * Camera properties are static information that describe the capabilities of
 * the camera. They remain constant through the lifetime of the Camera object.
 *
 * \return A ControlList of properties supported by the camera
 */
const ControlList &Camera::properties()
{
	return p_->pipe_->properties(this);
}

/**
 * \brief Retrieve all the camera's stream information
 *
 * Retrieve all of the camera's static stream information. The static
 * information describes among other things how many streams the camera
 * supports and the capabilities of each stream.
 *
 * \context This function is \threadsafe.
 *
 * \return An array of all the camera's streams
 */
const std::set<Stream *> &Camera::streams() const
{
	return p_->streams_;
}

/**
 * \brief Generate a default camera configuration according to stream roles
 * \param[in] roles A list of stream roles
 *
 * Generate a camera configuration for a set of desired stream roles. The caller
 * specifies a list of stream roles and the camera returns a configuration
 * containing suitable streams and their suggested default configurations. An
 * empty list of roles is valid, and will generate an empty configuration that
 * can be filled by the caller.
 *
 * \context This function is \threadsafe.
 *
 * \return A CameraConfiguration if the requested roles can be satisfied, or a
 * null pointer otherwise. The ownership of the returned configuration is
 * passed to the caller.
 */
std::unique_ptr<CameraConfiguration> Camera::generateConfiguration(const StreamRoles &roles)
{
	int ret = p_->isAccessAllowed(Private::CameraAvailable,
				      Private::CameraRunning);
	if (ret < 0)
		return nullptr;

	if (roles.size() > streams().size())
		return nullptr;

	CameraConfiguration *config = p_->pipe_->generateConfiguration(this, roles);
	if (!config) {
		LOG(Camera, Debug)
			<< "Pipeline handler failed to generate configuration";
		return nullptr;
	}

	std::ostringstream msg("streams configuration:", std::ios_base::ate);

	if (config->empty())
		msg << " empty";

	for (unsigned int index = 0; index < config->size(); ++index)
		msg << " (" << index << ") " << config->at(index).toString();

	LOG(Camera, Debug) << msg.str();

	return std::unique_ptr<CameraConfiguration>(config);
}

/**
 * \brief Configure the camera prior to capture
 * \param[in] config The camera configurations to setup
 *
 * Prior to starting capture, the camera must be configured to select a
 * group of streams to be involved in the capture and their configuration.
 * The caller specifies which streams are to be involved and their configuration
 * by populating \a config.
 *
 * The configuration is created by generateConfiguration(), and adjusted by the
 * caller with CameraConfiguration::validate(). This method only accepts fully
 * valid configurations and returns an error if \a config is not valid.
 *
 * 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.
 *
 * \context This function may only be called when the camera is in the Acquired
 * or Configured state as defined in \ref camera_operation, and shall be
 * synchronized by the caller with other functions that affect the camera
 * state.
 *
 * Upon return the StreamConfiguration entries in \a config are associated with
 * Stream instances which can be retrieved with StreamConfiguration::stream().
 *
 * \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 configured
 * \retval -EINVAL The configuration is not valid
 */
int Camera::configure(CameraConfiguration *config)
{
	int ret = p_->isAccessAllowed(Private::CameraAcquired,
				      Private::CameraConfigured);
	if (ret < 0)
		return ret;

	for (auto it : *config)
		it.setStream(nullptr);

	if (config->validate() != CameraConfiguration::Valid) {
		LOG(Camera, Error)
			<< "Can't configure camera with invalid configuration";
		return -EINVAL;
	}

	std::ostringstream msg("configuring streams:", std::ios_base::ate);

	for (unsigned int index = 0; index < config->size(); ++index) {
		StreamConfiguration &cfg = config->at(index);
		msg << " (" << index << ") " << cfg.toString();
	}

	LOG(Camera, Info) << msg.str();

	ret = p_->pipe_->invokeMethod(&PipelineHandler::configure,
				      ConnectionTypeBlocking, this, config);
	if (ret)
		return ret;

	p_->activeStreams_.clear();
	for (const StreamConfiguration &cfg : *config) {
		Stream *stream = cfg.stream();
		if (!stream) {
			LOG(Camera, Fatal)
				<< "Pipeline handler failed to update stream configuration";
			p_->activeStreams_.clear();
			return -EINVAL;
		}

		stream->configuration_ = cfg;
		p_->activeStreams_.insert(stream);
	}

	p_->setState(Private::CameraConfigured);

	return 0;
}

/**
 * \brief Create a request object for the camera
 * \param[in] cookie Opaque cookie for application use
 *
 * This method creates an empty request for the application to fill with
 * buffers and parameters, and queue for capture.
 *
 * The \a cookie is stored in the request and is accessible through the
 * Request::cookie() method at any time. It is typically used by applications
 * to map the request to an external resource in the request completion
 * handler, and is completely opaque to libcamera.
 *
 * The ownership of the returned request is passed to the caller, which is
 * responsible for either queueing the request or deleting it.
 *
 * \context This function is \threadsafe. It may only be called when the camera
 * is in the Configured or Running state as defined in \ref camera_operation.
 *
 * \return A pointer to the newly created request, or nullptr on error
 */
Request *Camera::createRequest(uint64_t cookie)
{
	int ret = p_->isAccessAllowed(Private::CameraConfigured,
				      Private::CameraRunning);
	if (ret < 0)
		return nullptr;

	return new Request(this, cookie);
}

/**
 * \brief Queue a request to the camera
 * \param[in] request The request to queue to the camera
 *
 * This method queues a \a request to the camera for capture.
 *
 * After allocating the request with createRequest(), the application shall
 * fill it with at least one capture buffer before queuing it. Requests that
 * contain no buffers are invalid and are rejected without being queued.
 *
 * Once the request has been queued, the camera will notify its completion
 * through the \ref requestCompleted signal.
 *
 * Ownership of the request is transferred to the camera. It will be deleted
 * automatically after it completes.
 *
 * \context This function is \threadsafe. It may only be called when the camera
 * is in the Running state as defined in \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 requests can't be queued
 * \retval -EINVAL The request is invalid
 * \retval -ENOMEM No buffer memory was available to handle the request
 */
int Camera::queueRequest(Request *request)
{
	int ret = p_->isAccessAllowed(Private::CameraRunning);
	if (ret < 0)
		return ret;

	/*
	 * The camera state may chance until the end of the function. No locking
	 * is however needed as PipelineHandler::queueRequest() will handle
	 * this.
	 */

	if (request->buffers().empty()) {
		LOG(Camera, Error) << "Request contains no buffers";
		return -EINVAL;
	}

	for (auto const &it : request->buffers()) {
		Stream *stream = it.first;

		if (p_->activeStreams_.find(stream) == p_->activeStreams_.end()) {
			LOG(Camera, Error) << "Invalid request";
			return -EINVAL;
		}
	}

	return p_->pipe_->invokeMethod(&PipelineHandler::queueRequest,
				       ConnectionTypeQueued, this, request);
}

/**
 * \brief Start capture from camera
 *
 * Start the camera capture session. Once the camera is started the application
 * can queue requests to the camera to process and return to the application
 * until the capture session is terminated with \a stop().
 *
 * \context This function may only be called when the camera is in the
 * Configured state as defined in \ref camera_operation, and shall be
 * synchronized by the caller with other functions that affect the camera
 * state.
 *
 * \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 = p_->isAccessAllowed(Private::CameraConfigured);
	if (ret < 0)
		return ret;

	LOG(Camera, Debug) << "Starting capture";

	ret = p_->pipe_->invokeMethod(&PipelineHandler::start,
				      ConnectionTypeBlocking, this);
	if (ret)
		return ret;

	p_->setState(Private::CameraRunning);

	return 0;
}

/**
 * \brief Stop capture from camera
 *
 * This method stops capturing and processing requests immediately. All pending
 * requests are cancelled and complete synchronously in an error state.
 *
 * \context This function may only be called when the camera is in the Running
 * state as defined in \ref camera_operation, and shall be synchronized by the
 * caller with other functions that affect the camera state.
 *
 * \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 = p_->isAccessAllowed(Private::CameraRunning);
	if (ret < 0)
		return ret;

	LOG(Camera, Debug) << "Stopping capture";

	p_->setState(Private::CameraConfigured);

	p_->pipe_->invokeMethod(&PipelineHandler::stop, ConnectionTypeBlocking,
				this);

	return 0;
}

/**
 * \brief Handle request completion and notify application
 * \param[in] request The request that has completed
 *
 * This function is called by the pipeline handler to notify the camera that
 * the request has completed. It emits the requestCompleted signal and deletes
 * the request.
 */
void Camera::requestComplete(Request *request)
{
	requestCompleted.emit(request);
	delete request;
}

} /* namespace libcamera */
generated by cgit v1.2.1 (git 2.18.0) at 2024-07-11 13:54:02 +0000