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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/thread.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()
: transform(Transform::Identity), 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::transform
* \brief User-specified transform to be applied to the image
*
* The transform is a user-specified 2D plane transform that will be applied
* to the camera images by the processing pipeline before being handed to
* the application. This is subsequent to any transform that is already
* required to fix up any platform-defined rotation.
*
* The usual 2D plane transforms are allowed here (horizontal/vertical
* flips, multiple of 90-degree rotations etc.), but the validate() function
* may adjust this field at its discretion if the selection is not supported.
*/
/**
* \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 &id,
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 id_;
std::set<Stream *> streams_;
std::set<const Stream *> activeStreams_;
private:
bool disconnected_;
std::atomic<State> state_;
};
Camera::Private::Private(PipelineHandler *pipe, const std::string &id,
const std::set<Stream *> &streams)
: pipe_(pipe->shared_from_this()), id_(id), 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,
|