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2019-06-11libcamera: ipa_manager: Fix handling of unset LIBCAMERA_IPA_MODULE_PATHNiklas Söderlund
If the environment variable LIBCAMERA_IPA_MODULE_PATH is not set utils::secure_getenv() will return a nullptr. Assigning a nullptr to a std::string is not valid and results in a crash, terminate called after throwing an instance of 'std::logic_error' what(): basic_string::_M_construct null not valid Fix this by operating directly on the returned char array instead of turning it into a std::string. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-11test: camera: Increase runtime for capture testNiklas Söderlund
Upstream commit 2978a505aaa981b2 ("media: vimc: stream: fix thread state before sleep") changes the frame rate when capturing from the vimc raw capture video nodes. The commit changes the frame rate from thousands of frames per second to to roughly fifty. The libcamera capture test was written with the assumption that vimc would keep providing this fast frame rate and ran for a very short time to decrease the overall run time of tests. This is no longer possible and the test fails as it can't capture enough frames in its runtime, increase the runtime to match the new vimc frame rate. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-11libcamera: geometry: Fix SizeRange constructor styleKieran Bingham
Match the style of the SizeRange() which specifies the hStep and vStep, and wrap the lines in pairs of min and max values. Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-06-11libcamera: pipeline: ipu3: Fix spellingKieran Bingham
Fix trivial spelling of queueing. Acked-by: Jacopo Mondi <jacopo@jmondi.org> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-06-11libcamera: pipeline: Fix 'request' grammarKieran Bingham
The PipelineHandler::completeBuffer documentation repeats the word 'request'. Remove the duplication and reformat the lines to fit. Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-06-10cam: Fix cam --help crashNiklas Söderlund
The cam utility does not terminate correctly if invoked with only --help. It prints the help information and then segfaults due to the application incorrectly handling the return value. Fix this by moving the return code check of the option parsing to main(). Reported-by: Emmanuel Arias <eamanu@eamanu.com> Suggested-by: Jacopo Mondi <jacopo@jmondi.org> Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-10libcamera: pipeline_handler: Optimise factory implementationLaurent Pinchart
The REGISTER_PIPELINE_HANDLER() macro defines and instantiates a subclass of the PipelineHandlerFactory class that specialises the virtual create() method. Now that create() does more than just creating an instance, boilerplate code gets duplicated between different factories. Factor out the instance creation code to a new virtual createInstance() method, and turn create() into a non-virtual method of the base class that can then be defined in the .cpp file. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-06-10test: camera: Fix initialisationKieran Bingham
Three tests {capture,configuration_set,statemachine} override the CameraTest::init() function, and call it as the first action. However they were not checking the return value, and each of the tests will segfault if the VIMC camera is not obtained. Check the return value of the CameraTest base class initialisation and return any errors to the test suite if initialisation fails. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-06-09Documentation: Use absolute paths for Doxygen EXCLUDE filesLaurent Pinchart
To avoid hardcoding a dependency between the source and build directories, use absolute paths for the Doxygen EXCLUDE files. The build directory can now be placed in any location, not just a direct subdirectory of the source directory. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-06-08libcamera: Use dependency instead of link_args to link against libdlLaurent Pinchart
Instead of specifying the link arguments directly, which may be compiler-specific, use a dependency object provided by find_library(). Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Paul Elder <paul.elder@ideasonboard.com> Tested-by: Paul Elder <paul.elder@ideasonboard.com>
2019-06-05libcamera: pipeline: vimc: add dummy IPAPaul Elder
Make the vimc pipeline handler get the dummy IPA, to show how an IPA can be acquired by a pipeline handler. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-05libcamera: test: remove test IPA and use dummy IPA insteadPaul Elder
Use the dummy IPA for testing/sample IPA instead of the earlier test IPA. Remove the test IPA, and update tests and meson accordingly. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-05libcamera: ipa: add dummy IPA implementationPaul Elder
Add a dummy IPA module. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-05libcamera: ipa_manager: implement class for managing IPA modulesPaul Elder
IPAManager is a class that will search in given directories for IPA modules, and will load them into a list. It also provides an interface for pipeline handlers to acquire an IPA. A meson build file for the IPAs is added, which also specifies a hard-coded path for where to load the IPAs from in the installation directory. More paths can be specified with the environment variable LIBCAMERA_IPA_MODULE_PATH, with the same syntax as the regular PATH environment variable. Make the test framework set this environment variable. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-05libcamera: ipa_module: match IPA module with pipeline handlerPaul Elder
Add a method to IPAModule to check if it matches with a given pipeline handler and pipeline version range. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-05libcamera: ipa_module: allow instantiation of IPAInterfacePaul Elder
Add functions for loading the IPAInterface factory function from an IPA module shared object, and for creating an instance of an IPAInterface. These functions will be used by IPAManager, from which a PipelineHandler will request an IPAInterface. Also update meson to add the "-ldl" linker argument, to allow loading of the factory function from a shared object. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-05libcamera: ipa_module: verify IPA module API version upon loadingPaul Elder
The IPA module API version determines the layout of struct IPAModuleInfo. If this version number does not match, then it means that the IPA module information structure can't be interpreted, and the module can't be used. Validate this version number upon loading the IPA module info from the IPA shared object. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-05libcamera: ipa_module_info: update struct to allow IPA matchingPaul Elder
We need a way to match pipelines with IPA modules, so add fields in IPAModuleInfo to hold the IPA module API version number, the pipeline name, and the pipeline version. The module API version is used to determine the layout of struct IPAModuleInfo. Also update IPA module tests and Doxygen accordingly. Doxygen needs to be updated to accomodate __attribute__((packed)). Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-05libcamera: pipeline: add namePaul Elder
In order to match an IPA module with a pipeline handler, the pipeline handler must have a name. Add a name attribute and getter to PipelineHandler such that it can automatically be defined by REGISTER_PIPELINE_HANDLER. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-05libcamera: ipa_interface: add headerPaul Elder
Define an IPAInterface class which will contain an IPA implementation. The methods that the IPAInterface exposes form the interface to the IPA implementation, hence the name. IPA module shared objects will implement this class. This also means that IPA module shared objects must be implemented in C++, so remove the C test IPA module. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-02libcamera: v4l2_device: Add META support in g/s_fmtJacopo Mondi
Add two operations to set and get format on devices implementing the V4L2 Metadata Interface, identified by the META_OUTPUT or META_CAPTURE capabilities. While at it, sort get/setFormat operations alphabetically and unify their style (eg. no empty line before ioctl). Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-02libcamera: v4l2_device: Add support for META_OUTPUTJacopo Mondi
Add support for output devices that expose the META_OUTPUT capabilities. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-06-02include: linux: Update Linux headers to v5.1Jacopo Mondi
Update kernel headers to v5.1 The most notable introduction for libcamera is support for V4L2_BUF_TYPE_META_OUTPUT. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-25cam: Add CamApp classNiklas Söderlund
Add more structure to main.cpp by breaking up the logic into a CamApp class. This makes the code easier to read and removes all of the organically grown global variables. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-25cam: capture: Break out capture to a new classNiklas Söderlund
Reduce the complexity of main.cpp by compartmentalising the capture logic into its own class. There is no functional change. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-25tests: list_formats: Fix argument names and add constNiklas Söderlund
Argument name differs from definition and implementation, fix it by renaming the definition. While at it make the argument const. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-23libcamera: Auto-generate libcamera.hLaurent Pinchart
As shown by two missing includes, keeping the libcamera.h file in sync when adding or removing headers is an error-prone manual process. Automate it by generating the header automatically. The libcamera.h header is also added to the libcamera dependency libcamera_dep to ensure that the headers gets generated before any source depending on it gets compiled. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-05-23meson: Create and use a dependency for libcamera and its headersLaurent Pinchart
Instead of manually adding the libcamera library and include path to every target that requires it, declare a dependency that groups the headers as source, the library and the include path, and use it through the project. This simplifies handling of the dependency. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-05-23meson: Fix coding style in meson.build filesLaurent Pinchart
Consistently go for 4 spaces indentation, and always put a space between the colon in argument lists, as per the examples from the meson documentation. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-23libcamera: camera: Simplify create() implementationLaurent Pinchart
Now that the Camera class inherits from std::enable_shared_from_this, we don't need to use std::allocate_shared anymore and can simplify the Camera::create() implementation. This fixes compilation with recent versions of libc++ whose std::allocate_shared implementation isn't compatible with classes that are not publicly constructible. The custom allocator is removed, but a custom deleter is needed as the Camera destructor is private. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-05-23cam: Rename conf variable referring to command line option to optLaurent Pinchart
Naming a variable that refers to command line options 'conf' is confusing as we using 'config' and 'cfg' to refer to camera and stream configurations. Rename it to 'opt'. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-05-23libcamera: camera: Add a validation API to the CameraConfiguration classLaurent Pinchart
The CameraConfiguration class implements a simple storage of StreamConfiguration with internal validation limited to verifying that the stream configurations are not empty. Extend this mechanism by implementing a smart validate() method backed by pipeline handlers. This new mechanism changes the semantic of the camera configuration. The Camera::generateConfiguration() operation still generates a default configuration based on roles, but now also supports generating empty configurations to be filled by applications. Applications can inspect the configuration, optionally modify it, and validate it. The validation implements "try" semantics and adjusts invalid configurations 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(), and pipeline handlers are guaranteed that the configuration they receive is valid. A reference to the Camera may need to be stored in the CameraConfiguration derived classes in order to access it from their validate() implementation. This must be stored as a std::shared_ptr<> as the CameraConfiguration instances belong to applications. In order to make this possible, make the Camera class inherit from std::shared_from_this<>. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-05-23libcamera: pipeline: Move camera data classes to the top level scopeLaurent Pinchart
Move the pipeline handler camera data classes, defined in the scope of the respective pipeline handler class, to the top level of the libcamera namespace. This prepares for the introduction of other classes that will make use of them in the IPU3 and RkISP1 pipeline handlers. The UVC and VIMC pipeline handlers are updated as well for consistency. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-05-23libcamera: camera: Return a pointer from generateConfiguration()Laurent Pinchart
To prepare for specialising the CameraConfiguration class in pipeline handlers, return a pointer to a camera configuration instead of a reference from Camera::generateConfiguration(). The camera configuration always needs to be allocated from the pipeline handler, and its ownership is passed to the application. For symmetry, change Camera::configure() to take a CameraConfiguration pointer instead of a reference. This aligns with our coding practice of passing parameters that are modified by the callee by pointer. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-05-23libcamera: Refactor the camera configuration storage and APILaurent Pinchart
Refactor the CameraConfiguration structure to not rely on Stream instances. This is a step towards making the camera configuration object more powerful with configuration validation using "try" semantics. The CameraConfiguration now exposes a simple vector-like API to access the contained stream configurations. Both operator[]() and at() are provided to access elements. The isEmpty() method is renamed to empty() and the methods reordered to match the std::vector class. As applications need access to the Stream instances associated with the configuration entries in order to associate buffers with streams when creating requests, expose the stream selected by the pipeline handler through a new StreamConfiguration::stream(). Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-05-23libcamera: Use stream roles directly instead of StreamUsageLaurent Pinchart
In order to prepare for an API overhall of the camera configuration generation, remove the StreamUsage class and replace its uses by stream roles. The size hints can't be specified anymore, and will be replaced with an API on the StreamConfiguration to negotiate configuration parameters with cameras. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-05-23libcamera: camera: Rename configureStreams() and streamConfiguration()Laurent Pinchart
Rename the configureStreams() and streamConfiguration() methods to configure() and generateConfiguration() respectively in order to clarify the API. Both methods deal with CameraConfiguration objects, and are thus not limited to streams, even if a CameraConfiguration currently contains streams only. While at it, remove the qcam MainWindow::configureStreams() method that is declared but never defined or used. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-05-21test: ipa: add IPAModule testsPaul Elder
Add tests to test the the IPAModule class, for loading the IPA module info from IPA module .so shared objects, with modules written in both C and C++. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-21libcamera: ipa_module: add IPA shared library modulePaul Elder
Implement a class to wrap around an IPA module shared object. For now, just load a struct IPAModuleInfo with symbol name ipaModuleInfo from an IPA module .so shared object. Also provide a public header file including the struct IPAModuleInfo, structured such that both C and C++ IPA modules are supported. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-18libcamera: pipeline: rkisp1: Fix usage of uninitialised variableLaurent Pinchart
Commit 1a813a5c3ab7 introduced usage of an uninitialised variable. Fix it. Fixes: 1a813a5c3ab7 ("libcamera: media_device: Handle media device fd in acquire() and release()") Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-05-18libcamera: camera: Fix std::ostringstream initialisationLaurent Pinchart
We use the std::ostringstream class to generate log messages in the Camera class. The stream is initialised with initial content, but is not opened without seeking to the end, which results in the content being overwritten immediately. Fix it by opening the stream with std::ios_base::ate. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-05-17test: v4l2_device: Switch most tests to vimcNiklas Söderlund
The vimc driver delivers frames much faster then the vivid driver hence most v4l2 device tests complete much quicker if vimc is used. The only v4l2 device test which can't be switched is buffer_sharing as it needs to import buffers somewhere, something vimc do not support. With this change I manage to shave of almost 7 seconds for each run of all v4l2 device tests. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-17test: v4l2_device: Reset media links and set a resolutionNiklas Söderlund
When initializing the test reset any media links and set a know resolutions. This is needed to put the device under test into known state and not have the v4l2 device tests depend on that no one have touched the device before the test is executed. The resolution is picked purely at random and could possibly be moved to each test case if there is a need for different resolutions for a specific one. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-17test: v4l2_device: Allow each test to specify which device and entity to testNiklas Söderlund
Prepare for different tests which implements V4L2DeviceTest to specify which media device and entity they wish to test. There is no functional changes, all tests still use vivid to perform there tests. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Acked-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-17test: v4l2_device: Implement functions inside class definition in cpp filesNiklas Söderlund
Align the style of the formats test with the other v4l2_device tests by impending the functions in the class definition instead of first declaring the class and then implement the functions. There is no functional change only restructuring of existing code to align with the style of other tests. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-17test: v4l2_device: Order class sectionsNiklas Söderlund
Order the sections of a class public, protected and private. There is no functional change only restructuring of existing code to align with the style of other tests. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-17libcamera: camera: Lock the pipeline handler in acquire()Niklas Söderlund
To allow more than one application using libcamera simultaneously there can be no overlap between which cameras are in use by which user. As a camera is part of a pipeline handler and there might be shared resources between all cameras exposed by that pipeline handler it's not enough to to only lock access to a single camera, all cameras from that pipeline need to be tied to the same process. Allow for this by locking the whole pipeline when one of its cameras is acquired by the user. Other processes can still enumerate and list all cameras in the system but can't acquire a camera from a locked pipeline handler. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-17libcamera: pipeline_handler: Add functions to lock a whole pipelineNiklas Söderlund
Add lock() and unlock() which are backed by the MediaDevice implementation and lock all media devices claimed by a pipeline handler instance. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-17libcamera: pipeline_handler: Keep track of MediaDeviceNiklas Söderlund
Instead of requiring each pipeline handle implementation to keep track of calling release() on its media devices upon deletion, keep track of them in the base class. Add a helper that pipeline handlers shall use to acquire a media device instead of directly interacting with the DeviceEnumerator. This also means that pipeline handler implementations do no need to keep a shared_ptr<> reference to the media devices they store locally as the PipelineHandler base class will keep a shared_ptr<> reference to all media devices consumed for the entire lifetime of the pipeline handler implementation. Centrally keeping track of media devices will also be beneficial to implement exclusive access to pipelines across processes. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-05-17libcamera: media_device: Add functions to lock device for other processesNiklas Söderlund
Add lock() and unlock() which are backed by lockf() and allow an instance of libcamera to claim exclusive access to a media device. These functions are the base of allowing multiple user of libcamera to coexist in the system without stepping on each other's toes. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>