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2020-03-06libcamera: controls: Return control by valueLaurent Pinchart
The ControlList::get() and ControlValue::get() methods return the control value by reference. This requires the ControlValue class to store the control value in the same form as the one returned by those functions. For the array controls that are soon to be added, the ControlValue class would need to store a span<> instance in addition to the control value itself, which would increase the required storage space. Prepare for support of array controls by returning from get() by value. As all control values are 8 bytes at most, this doesn't affect efficiency negatively. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-03-06libcamera: controls: Decouple control and value type in ControlList::set()Laurent Pinchart
The ControlList::set() method takes a reference to a Control<T>, and requires the value to be a reference to T. This prevents the set() method from being used with value types that are convertible to T, and in particular with std::array or std::vector value types when the Control type is a Span<> to support array controls. Fix this by decoupling the control type and value type in the template parameters. The compiler will still catch invalid conversions, including cases where the constructor of type T from the value type is explicit. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-03-06libcamera: controls: Don't convert 32-bit and 64-bit implicitlyLaurent Pinchart
The ControlValue::get<T>() method verifies that the T type corresponds to the ControlValue type. It however accepts int32_t as a return type for 64-bit integer controls, and int64_t as a return type for 32-bit integer controls. There's no reason to do so anymore, make the type check stricter. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-03-06libcamera: controls: Reorder ControlValue methodsJacopo Mondi
Reorder functions in ControlValue class to group const methods together. Cosmetic change only. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-03-06libcamera: ipa: Test control structure size with static_assertLaurent Pinchart
The control-related structures ipa_controls_header, ipa_control_value_entry and ipa_control_range_entry define the IPA protocol and are thus part of the ABI. To avoid breaking it inadvertently, use static_assert() to check the size of the structures. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-03-06libcamera: ipa: Make <ipa/ipa_controls.h> self-containedLaurent Pinchart
The <ipa/ipa_controls.h> header makes use of uint*_t types, but doesn't include stdint.h. Fix it, and include ipa_controls.h in ipa_controls.cpp to test compilation of the header on its own. While at it, fix the comment as the top of ipa_controls.cpp to refer to the correct file name. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-03-06libcamera: ipa: Remove unused IPA control typesJacopo Mondi
The ipa_control_range_data structure is only used to document the IPA control serialization format, but isn't used in code at all as the ControlRange entries are directly serialized to a byte stream buffer. This applies to the ipa_control_value_data structure that is solely used by ipa_control_range_data. Expand the documentation of the IPA control serialization format to describe the layout of the control range data in words and diagrams instead of through a C structure. Remove the unused structures as a result. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-03-06libcamera: gen-controls: Fix documentation issue with <<Jacopo Mondi
Doxygen fails to parse entries with multiple << signs as, in example, \var extern const Control<Span<int32_t>> Remove the type from the control documentation as unique control and property names should not need any additional information specified for Doxygen to correctly identify them. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-03-06test: Add Span testLaurent Pinchart
Add a compile-only test that exercises the whole Span API, as template functions are not fully compile-tested when the file is parsed. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-03-06libcamera: Add a C++20-compliant std::span<> implementationJacopo Mondi
C++20 will contain a std::span<> class that provides view over a contiguous sequence of objects, the storage of which is owned by some other object. Add a compatible implementation to the utils namespace. This will be used to implement array controls. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-02-24tests: Remove IPA_MODULE_PATH environment variableKieran Bingham
The tests declare a hard-coded LIBCAMERA_IPA_MODULE_PATH to allow tests to run from the test-suite. This requires tests to be run only from the root of the build directory, otherwise (for example, by running in their local directory) they will not be able to correctly locate the IPA modules. Now that the build path for the IPA manager is determined at runtime we can remove the redundant setting of the LIBCAMERA_IPA_MODULE_PATH for tests. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-24libcamera: ipa_manager: Search for IPA libraries in build treeKieran Bingham
When libcamera is built and tested (or used at all) before installing to the configured prefix path, it will be unable to locate the IPA binaries, or IPA binaries previously installed in the system paths may be incorrect to load. Utilise the build_rpath dynamic tag which is stripped out by meson at install time to determine at runtime if the library currently executing has been installed or not. When not installed and running from a build tree, identify the location of that tree by finding the path of the active libcamera.so itself, and from that point add a relative path to be able to load the most recently built IPA modules. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-24libcamera: ipa_manager: Allow recursive parsingKieran Bingham
Provide an optional means to recurse into subdirectories to search for IPA libraries. This allows IPAs contained within their own build directory to be found when loading from a non-installed build. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-24libcamera: ipa_manager: Simplify addDir() usageKieran Bingham
The addDir call only returns an error if it can't open the directory. Callers only care about the number of modules added, and discard any error information. Simplify the return value and calling code by returning an unsigned int of the number of modules loaded. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-24libcamera: ipa_manager: Re-arrange IPA precedenceKieran Bingham
Setting a user environment path in LIBCAMERA_IPA_MODULE_PATH should take precedence over the system loading locations. Adjust the IPA search orders accordingly. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-24libcamera: utils: Add a C++ dirname implementationKieran Bingham
Provide a std::string based implementation which conforms to the behaviour of the dirname() fucntion defined by POSIX. Tests are added to cover expected corner cases of the implementation. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-19qcam: Fix compilation errors with clang-10Laurent Pinchart
clang-10 has introduced the same deprecated-copy warning that appeared in gcc-9 and caused build issues with Qt header files. However, the clang version seems more sensitive, and detects issues that are not fixed in Qt 5.13, unlike gcc-9. Extend the logic that disables the warning for gcc-9 and Qt < 5.13 to cover clang-10 and all Qt versions. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-02-19qcam: Use standard PicturesLocation path for captureKieran Bingham
Utilise the QStandardPaths::PicturesLocation as a starting point for saving images from qcam. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-19libcamera: media_device: Use Loggable interfaceKieran Bingham
Extend MediaDevice to inherit from the Loggable interface to support a logPrefix which presents the device node path, and the driver name. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-19libcamera: media_device: prevent sign extension on castsKieran Bingham
The conversion of pointers to integers is implementation defined and differs between g++ and clang++ when utilising a uint64_t type. #include <iostream> int main(int argc, char **argv) { void *ptr = reinterpret_cast<void *>(0xf1234567); uint64_t u64 = reinterpret_cast<uint64_t>(ptr); uint64_t uint64 = reinterpret_cast<uintptr_t>(ptr); std::cout << "ptr " << ptr << " ptr -> u64 0x" << std::hex << u64 << " ptr -> uintptr_t -> u64 0x" << std::hex << uint64 << std::endl; return 0; } When compiled with g++ for a 32-bit platform produces the following unexpected output: ptr 0xf1234567 ptr -> u64 0xfffffffff1234567 ptr -> uintptr_t -> u64 0xf1234567 The standards states: "A pointer can be explicitly converted to any integral type large enough to hold all values of its type. The mapping function is implementation-defined. [Note: It is intended to be unsurprising to those who know the addressing structure of the underlying machine. — end note]" And as such the g++ implementation appears to be little more surprising than expected in this situation. The MediaDevice passes pointers to the kernel via the struct media_v2_topology in which pointers are cast using a uint64 type (__u64), which is affected by the sign extension described above when BIT(32) is set and causes an invalid address to be given to the kernel. Ensure that we cast using uintptr_t which is not affected by the sign extension issue. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-02-18libcamera: Use C++14 std::*_t type traitsLaurent Pinchart
C++14 introduced useful type traits helpers named std::*_t as aliases to std::*<...>::type. Use them to simplify the code. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2020-02-18libcamera: device_enumerator: Don't stop if one device failsLaurent Pinchart
If one device fails to enumerate, which isn't supposed to happen under normal conditions, both the sysfs and the udev enumerators stop enumeration of further devices. This potentially prevents working devices from being detected and handled. Fix it by skipping the faulty device. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Tested-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-02-18test: camera: buffer_import: Don't include <random>Laurent Pinchart
The <random> header isn't needed since commit 6e1e847753fd ("test: camera: buffer_import: Update to FrameBuffer restrictions"). Don't include it. 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>
2020-02-14android: camera_device: Use Camera properties for static MetadataJacopo Mondi
Construct two example static metadata to be reported to the Android framework using the properties reported by the Camera. Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-02-14libcamera: camera: Add Camera propertiesJacopo Mondi
Add a method to the Camera class to retrieve the Camera properties registered by the pipeline handler. While at it, reword the Camera::controls() operation documentation to specify that the camera control information are constant during the camera lifetime not their value, while the camera properties value are the actually static information. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-02-14libcamera: pipeline_handler: Add Camera propertiesJacopo Mondi
Associate to each Camera a ControlList which contains the Camera properties as created by pipeline handlers in the pipeline handler's CameraData and provide an operation to retrieve them. Collect properties from the camera sensor in all pipeline handlers that support one (IPU3, RKISP1 and VIMC). Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-02-14libcamera: camera_sensor: Parse camera propertiesJacopo Mondi
Parse and collect camera sensor properties by inspecting the associated v4l2 controls. Augment the CameraSensor class with an operation to retrieve the collected properties. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-02-14libcamera: controls: Add default to ControlRangeJacopo Mondi
Augment the the ControlRange class to store the control default value. This is particularly relevant for v4l2 controls used to create Camera properties, which are constructed using immutable video device properties, whose value won't change at runtime. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-02-14libcamera: properties: Add rotation propertyJacopo Mondi
The rotation property describes the rotation of the camera sensor. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-02-14libcamera: properties: Add location propertyJacopo Mondi
Re-use the Control generation infrastructure to generate libcamera properties and define the first 'Location' property. Introduce three additional files: - include/libcamera/property_ids.h Defines the properties ids - src/libcamera/property_ids.cpp Defines the properties Control<> instances - src/libcamera/property_ids.yaml Provide the first 'Location' property definition. Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-02-14libcamera: controls: Parse 'enum' in gen-controls.pyJacopo Mondi
In preparation to add libcamera Camera properties definitions by re-using the control generation framework, augment the gen_controls.py script to support parsing the 'enum' yaml tag and generate documentation and definition of possible values associated with a Control or a Property and defined through an enumeration of supported values. Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-02-14include: linux: Update v4l2-controls.hJacopo Mondi
Import a temporary version of the v4l2-controls.h with the newly added definition of V4L2_CID_CAMERA_SENSOR_LOCATION and V4L2_CID_CAMERA_SENSOR_ROTATION controls. Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-02-14test: thread: Test waiting on a thread that is not runningLaurent Pinchart
Test that Thread::wait() on a thread that hasn't been started, or on a thread that is known to have completed, returns without a timeout. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-02-14test: threads: Add wait() timeout testLaurent Pinchart
Add a test case to wait with a timeout, testing both a too short and a long enough duration. 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>
2020-02-14libcamera: thread: Support timeout in wait() functionLaurent Pinchart
Add a parameter to the Thread::wait() function to wait with a timeout. The delay value utils::duration::max() waits forever. 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>
2020-02-14qcam: Provide save image functionalityKieran Bingham
Implement a save image button on the toolbar which will take a current viewfinder image and present the user with a QFileDialog to allow them to choose where to save the image. Utilise the QImageWriter to perform the output task. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-14qcam: Provide initial icon buttons "Play/Stop"Kieran Bingham
Provide Quit, Play, Stop icons. Create a Qt resource to compile icons into the binary and present them on the toolbar. Update the Quit button with a 'cross', and implement Play/Stop buttons. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-14qcam: assets: Provide initial icon setKieran Bingham
Provide simple clean icons from https://feathericons.com/ (https://github.com/feathericons/feather) These are provided under the MIT license. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-14qcam: Introduce a toolbar and camera switchingKieran Bingham
Implement a quit button, and a list of cameras. Selecting a different camera from the Toolbar will stop the current stream, and start streaming the chosen camera device if it can be acquired. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-14qcam: Store CameraManager as class memberKieran Bingham
Intialise a local copy of the CameraManager instance to ease access to the CameraManager which is frequently utilised. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-14qcam: Move requestCompleted signal mappingKieran Bingham
The MainWindow connects a handler to the Camera requestCompleted signal when the camera is opened, but never disconnects it. Move the connection to the startCapture() function, and ensure that it is disconnected again when the stream is stopped. This ensures that we can successfully tear down the stream, and restart with a new camera. Introducing the error_disconnect cleanup path in start_capture identified that we left the camera in the start state, thus we also add a call to camera->stop() when disconnecting the signal connection. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-14qcam: Tie FrameBufferAllocator to stream lifeKieran Bingham
The FrameBufferAllocator must be deleted and reconstructed before performing any reconfiguration of the stream. Construct the allocator at startCapture, and destroy it during stopCapture so that we can successfully stop and restart the stream. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-13libcamera: v4l2_videodevice: Add crop/selection controlNaushir Patuck
Add control for cropping/selection on a V4L2 video device through the VIDIOC_S_SELECTION ioctl. This is similar to the existing cropping control available on V4L2 sub-devices. Signed-off-by: Naushir Patuck <naush@raspberrypi.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-13libcamera: Standardize on doxygen \returnKieran Bingham
Two occasions in the source utilise the Doxygen '\returns' alias for \return. We use \return everywhere else in the code. Update the two occurences to match. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-13libcamera: ipa_manager: Use utils::split()Laurent Pinchart
Replace the custom string splitting implementation with utils::split(). Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> [Kieran: Re-fit to master branch] Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-02-13test: Add a utils::split() testLaurent Pinchart
The test constructs a string by joining substrings, splits it, and verifies that the original and resulting substrings match. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-02-13libcamera: utils: Add string splitter utility functionLaurent Pinchart
Add a utils::split() function that splits a string for the purpose of iterating over substrings. It returns an object of unspecified type that can be used in range-based for loops. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-02-13utils: rkisp1: sync topology with upstream driver in capture scriptHelen Koike
rkisp1 kernel driver was merged upstream with minor changes in the topology from the original driver libcamera based it's first support to rkisp1. Adapt libcamera capture script to work with upstream driver. * Remove subdevice dphy from the pipeline. * Add resizer in the pipeline. * Fix links. * Update entity names. Signed-off-by: Helen Koike <helen.koike@collabora.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2020-02-13libcamera: pipeline: rkisp1: sync topology with upstream driverHelen Koike
rkisp1 kernel driver was merged upstream with minor changes in the topology from the original driver libcamera based it's first support to rkisp1. Adapt libcamera pipeline to work with upstream driver. * Remove subdevice dphy from the pipeline. * Add resizer in the pipeline. * Fix links. * Update entity names. Signed-off-by: Helen Koike <helen.koike@collabora.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2020-02-13meson.build: Silence the C99 designators warningLaurent Pinchart
We use array designators for array initialization, which is a C99 extension. clang-10 warns about it, causing a build failure. As this is a useful extension, silence the warning. This needs to be done only if the compiler supports the -Wno-c99-designator argument, otherwise a -Wunknown-warning-option will be generated. 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>