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2019-10-08ipa: vimc: Rename ipa_dummy to ipa_vimcJacopo Mondi
The DummyIPA is actually a test IPA module for the virtual media controller driver VIMC. Rename it accordingly to its usage. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2019-10-07test: timer: Test start() with absolute deadlineLaurent Pinchart
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-10-07test: timer-thread: Test starting a timer from another threadLaurent Pinchart
Timers can't be started from another thread. Ensure that attempting to do so fails. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-10-07test: timer: Test that a timer can be restarted before it expiresLaurent Pinchart
The Timer API allows restarting a timer before it expires. Add a corresponding test. The test fails as the Timer class doesn't comply with its API documentation. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-10-07test: timer: Test that deadline() isn't reset upon time outLaurent Pinchart
Verify that the timer deadline stays valid after the timer expires. As the test now uses the deadline in order to compute the jitter, the interval_ field isn't used anymore and can be removed. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-10-05libcamera: controls: Use ControlValidator to validate ControlListLaurent Pinchart
Replace the manual validation of controls against a Camera with usage of the new ControlValidator interface. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-10-05libcamera: controls: Rename ControlInfo to ControlRangeLaurent Pinchart
The ControlInfo class stores a range of valid values for a control. Its name is vague, as "info" has multiple meanings. Rename it to ControlRange. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-10-05libcamera: controls: Remove ControlInfo::idLaurent Pinchart
The ControlInfo id member is only used in the toString() method of the class, and nowhere else externally. The same way that ControlValue doesn't store a ControlId, ControlInfo shouldn't. Remove it. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-10-05libcamera: controls: Remove the unused ControlList::update() methodLaurent Pinchart
The ControlList::update() method is unused. While it is meant to fulfil a need of applications, having no user means that it is most probably not correctly designed. Remove the method, we will add it back later if needed. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-10-04libcamera: controls: Improve the API towards applicationsLaurent Pinchart
Rework the control-related classes to improve the API towards applications. The goal is to enable writing code similar to Request *req = ...; ControlList &controls = req->controls(); controls->set(controls::AwbEnable, false); controls->set(controls::ManualExposure, 1000); ... int32_t exposure = controls->get(controls::ManualExposure); with the get and set operations ensuring type safety for the control values. This is achieved by creating the following classes: - Control defines controls and is the main way to reference a control. It is a template class to allow methods using it to refer to the control type. - ControlId is the base class of Control. It stores the control ID, name and type, and can be used in contexts where a control needs to be referenced regardless of its type (for instance in lists of controls). This class replaces ControlIdentifier. - ControlValue is kept as-is. The ControlList class now exposes two template get() and set() methods that replace the operator[]. They ensure type safety by infering the value type from the Control reference that they receive. The main way to refer to a control is now through the Control class, and optionally through its base ControlId class. The ControlId enumeration is removed, replaced by a list of global Control instances. Numerical control IDs are turned into macros, and are still exposed as they are required to communicate with IPAs (especially to deserialise control lists). They should however not be used by applications. Auto-generation of header and source files is removed for now to keep the change simple. It will be added back in the future in a more elaborate form. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-10-04libcamera: controls: Use explicit 32-bit integer typesLaurent Pinchart
Make the control API more explicit when dealing with integer controls by specifying the size. We already do so for 64-bit integers, using int64_t and ControlTypeInteger64, do the same for 32-bit integers. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-10-04libcamera: controls: Make ControlValue get/set accessors template methodsLaurent Pinchart
The ControlValue get accessors are implemented with functions of different names, whlie the set accessors use polymorphism to support different control types. This isn't very consistent and intuitive. Make the API clearer by using template methods. This will also have the added advantage that support for the new types will only require adding template specialisations, without adding new methods. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-10-04libcamera: controls: Rename ControlValueType to ControlTypeLaurent Pinchart
The type of a control value is also the type of the control. Shorten the ControlValueType enumeration to ControlType, and rename ControlValue* to ControlType* for better clarity. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-09-16test: buffer_import: Initialize video_ to nullptrJacopo Mondi
When the vivid module used to test buffer importing is not loaded, the test correctly bails out, but during the clean up procedure tries to access the video_ field, which, if not correctly initialized to nullptr contains random values and accessing it causes a segfault. Fix this by initializing video_ field to nullptr to make sure it is properly handled in cleanup(). Fixes: e1a5873701a9 ("test: camera: Add buffer import and mapping test") Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2019-09-14libcamera: Switch to the std::chrono APILaurent Pinchart
Replace the clock_gettime()-based API with durations expressed as integers with the std::chrono API. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-09-13test: process: Extend timeout durationKieran Bingham
The process test runs for just 100mS. The spawned process runs for at least 50mS. Ordinarily this should allow plenty of time for both the process to be spawned and run, but when adding extra debug instrumentation, the processes can be slowed down, leading to a false negative test failure. Extend the timeout to 2 seconds to allow the short process to be run correctly - but use the now initialised exitStatus_ to exit the event loop as soon as the process has completed. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-09-13test: process: Initialise member variablesKieran Bingham
The ProcessTest() declares member variables but leaves them unitialised. Set them appropriately from the constructor. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-09-13test: process: Connect signal before launching processKieran Bingham
The procFinished event handler is registered after the process is started. This doesn't actually create any race, as the finished signal is emitted after a SIGCHLD is caught and handled through the ProcessManager and processed by the event loop. However, to follow the best practice that resources should be acquired before performing an action, connect the finished signal before starting the process. Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2019-08-19libcamera: camera_manager: Construct CameraManager instances manuallyLaurent Pinchart
The CameraManager class is not supposed to be instantiated multiple times, which led to a singleton implementation. This requires a global instance of the CameraManager, which is destroyed when the global destructors are executed. Relying on global instances causes issues with cleanup, as the order in which the global destructors are run can't be controlled. In particular, the Android camera HAL implementation ends up destroying the CameraHalManager after the CameraManager, which leads to use-after-free problems. To solve this, remove the CameraManager::instance() method and make the CameraManager class instantiable directly. Multiple instances are still not allowed, and this is enforced by storing the instance pointer internally to be checked when an instance is created. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-08-19test: camera: Use the CameraManager from the CameraTest base classLaurent Pinchart
Make the camera manager a protected field of the CameraTest class, and use it instead of CameraManager::instance() in the camera tests. This prepares for the removal of CameraManager::instance(). Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-08-19test: Get event dispatcher from current threadLaurent Pinchart
For all tests that don't otherwise require access to the camera manager, get the event dispatcher from the current thread instead of the camera manager. This prepares for the removal of CameraManager::instance(). Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-08-19test: unixsocket: Fix typo in error messageLaurent Pinchart
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-08-19test: event-thread: Fix compilation on Chromium OSLaurent Pinchart
Commit 92b4af98cd67 ("test: Add EventNotifier thread move test") causes the build to fail in the Chromium OS build environment, because the return values of the pipe() function marked with the __warn_unused_result__ attribute is ignored. Fix this. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-08-17test: Simplify tests with parent-child relationshipsLaurent Pinchart
Create object instances with a parent to avoid the need for reparenting objects manually. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-08-17test: object: Extend object test to verify parent-child relationshipsLaurent Pinchart
The test verifies correct behaviour of parent-child relationships in relation to thread affinity. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-08-17test: Add Timer thread move testLaurent Pinchart
The test verifies correct behaviour of a running timer moved to a different thread. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-08-17test: Add EventNotifier thread move testLaurent Pinchart
The test verifies correct behaviour of an enabled event notifier moved to a different thread. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-08-17test: Add Object class thread affinity testLaurent Pinchart
The test verifies thread affinity and thread move notifications. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-08-17test: Add Object::invokeMethod() testLaurent Pinchart
The test verifies correct behaviour of asynchronous method invocation for Object instances. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-08-13test: v4l2_device: Remove unused functionKieran Bingham
The 'exists()' call is not used within the code base. Remove it. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-08-13test: v4l2_videodevice: Add M2M device testKieran Bingham
The V4L2M2MDevice requires two video devices to be configured. This makes it unsuitable to reuse the existing V4L2DeviceTest test library in its current form. Implement a full test to run the two M2M pipelines through VIM2M. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-08-11tests: camera-sensor: Test using invalid media bus formatNiklas Söderlund
Linux commit b6c61a6c37317efd ("media: vimc: propagate pixel format in the stream") changes the sensor in the vimc media graph to accept all media bus format currently described in Linux. This prevents the camera-sensor test case to verify that a supported media bus format is selected from a list of defined formats, fix this by using an invalid media bus format in the test case. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-08-11tests: v4l2_videodevice: Set media bus and pixel formats for vimcNiklas Söderlund
Most of the video device tests are based on vimc and Linux commit 85ab1aa1fac17bcd ("media: vimc: deb: fix default sink bayer format") changes the default media bus format for the debayer subdevices. This leads to a -EPIPE error when trying to use the raw capture video device nodes. Fix this by explicitly setting media bus and pixel formats to known good values which works before and after the upstream change. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-08-11libcamera: pipeline: vimc: Switch to using the RGB/YUV Capture video nodeNiklas Söderlund
Linux commit 85ab1aa1fac17bcd ("media: vimc: deb: fix default sink bayer format") which is part of v5.2 changes the default media bus format for the debayer subdevices. This leads to a -EPIPE error when trying to use the raw capture video device nodes. Fix this by moving the vimc pipeline to use the RGB/YUV Capture capture video node. As a consequence of this change the scaler in the vimc pipeline is used and a hard coded upscale of 3 is present in the video pipeline. This limits the sizes exposed and accepted by libcamera to multiples of 3. Update the buffer import test case to match this new format constraint by setting the resolution to 1920x1080, a resolution which works with both vimc and vivid. With this new resolution the buffer import test takes a bit more time to complete 60 buffers and it's runtime also needs to be increased. The raw capture video node still needs to be handled by the pipeline as its format needs to be updated to allow the pipeline format validation to pass. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-08-01test: camera: buffer_import: clear video pointerKieran Bingham
The FrameSink::cleanup() call checks if video_ is set before cleaning up and then deleting the object. If the cleanup() call is called twice for any reason, this will encounter a use-after-free as the video_ pointer is not cleared after deletion. Whilst cleanup() is not currently called twice consecutively, to prevent errors in the future, make it explicit that the object has been deleted by clearing the stale pointer. 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>
2019-07-17test: logging: move logging tests to a subdirectoryPaul Elder
Since there are two logging tests now, move them to their own subdirectory. Update meson as necessary. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-07-17test: logging: add logging process testPaul Elder
Add a test to test that logging works in isolated child processes. Only logSetFile is tested, because stdout and stderr are closed for isolated child processes, and syslog and the none logging destinations are expected to be the same as non-isolated processes. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-07-17test: logging: add logSetStream testPaul Elder
Test the new logSetStream logging API call. Reorganize the logging API tests at the same time. logSetTarget for the syslog logging destination is not tested. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-07-16libcamera: message: Add user message typesJacopo Mondi
Reserve identifiers for user-defined message types and add an operation to the Message class to register the type identifiers. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2019-07-14test: camera: Add buffer import and mapping testJacopo Mondi
Test buffer importing and mapping by streaming the VIMC camera to VIVID video output device performing zero-copy memory sharing using dmabuf file descriptors. The test cycle 20 buffers between the camera and the output with a 1:1 buffer index to dmabuf fd mapping, then randomises the mapping with the same number of buffers on each side for 20 more frames, to finally increase the number of buffers on the output side for the 20 last frames. No remapping of dmabuf fd to buffer index should occur for the first 40 frames. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-07-14libcamera: Stop using Stream::bufferPool to get the number of buffersLaurent Pinchart
The cam and qcam applications, as well as the camera capture test case, access the Stream::bufferPool in order to know how many requests to initially queue. As part of an effort to remove access to the buffer pool from applications, use the buffer count from the stream configuration instead. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-07-14libcamera: v4l2_videodevice: Signal buffer completion at streamoff timeLaurent Pinchart
When stopping the stream buffers have been queued, in which case their completion is never be notified to the user. This can lead to memory leaks. Fix it by notifying completion of all queued buffers with the status set to error. As a result the base PipelineHandler implementation can be simplified, as all requests complete as the result of stopping the stream. The stop() method that manually completes all queued requests isn't needed anymore. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-07-14libcamera: buffer: Split memory information to BufferMemoryLaurent Pinchart
The Buffer class is a large beast the stores information about the buffer memory, dynamic metadata related to the frame stored in the buffer, and buffer reference data (in the index). In order to implement buffer import we will need to extend this with dmabuf file descriptors, making usage of the class even more complex. Refactor the Buffer class by splitting the buffer memory information to a BufferMemory class, and repurposing the Buffer class to reference a buffer and to store dynamic metadata. The BufferMemory class becomes a long term storage, valid and stable from the time buffer memory is allocated to the time it is freed. The Buffer class, on the other hand, becomes transient, is created on demand when an application requires a buffer, is given to a request, and is deleted when the request completes. Buffer and BufferMemory don't need to be copied, so their copy constructor and assignment operators are deleted. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-07-14libcamera: v4l2_videodevice: Add helper to queue all buffersLaurent Pinchart
When starting the stream on a capture video device it is often needed to queue all the allocated buffers. Add a helper method to do so, and refactor the existing queueBuffer() method to make it clearer. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2019-07-13test: v4l2_videodevice: buffer_sharing: Lower resolution to speed up testLaurent Pinchart
Lower the resolution to the smallest vivid supports, 320x180, in order to speed up the test. This isn't enough in itself as the frame rate also has to be configured, but the V4L2VideoDevice class doesn't support frame rate control yet. In the meantime the frame rate can be set manually with yavta or v4l2-ctl. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
2019-07-12test: logging: fix compilation on Chromium OSPaul Elder
Commit a25c937f8afe ("test: add logging API test") causes the build to fail in the Chromium OS build environment, because the return value of a function call marked with the __warn_unused_result__ attribute is ignored. Fix this. Fixes: a25c937f8afe ("test: add logging API test") Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-07-12libcamera: add IPA proxyPaul Elder
Add an IPAProxy class whose implementations will act as a proxy between a pipeline handler and an isolated IPA interface. Also add an IPAProxyFactory that will construct the IPAProxy implementations as necessary. Update Doxygen to ignore the directory where IPAProxy implementations will reside. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-07-12libcamera: Add Process and ProcessManager classesPaul Elder
Add a Process class to abstract a process, and a ProcessManager singleton to monitor and manage the processes. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-07-12libcamera: ipa_module_info: add license fieldPaul Elder
Add a field to IPAModuleInfo to contain the license of the module. This license field will be used to determine whether the IPA module should be run in an isolated process or not. If the license is open source, then the IPA module will be allowed to run without process isolation, if the user enables it. If the license is not open source, then the IPA module will be run with process isolation. Update the dummy IPA and IPA test to conform to the new struct layout. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2019-07-12test: add logging API testPaul Elder
Test that setting the log file and log levels works from an application point of view. The test uses the internal logging mechanism as well, just to write to the log file. Signed-off-by: Paul Elder <paul.elder@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>