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2020-07-08libcamera: Use Size::isNull()Laurent Pinchart
Use the new Size::isNull() function through the code base to replace manual checks. While the new code isn't equivalent, as isNull() checks that both width and height are zero, it catches the same conditions in practice. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Umang Jain <email@uajain.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2020-07-07android: camera_device: Remove single buffer restriction.Kieran Bingham
A capture request is no longer limited to a single output buffer. Remove the limitation, but (for now) keep the check to ensure that at least one buffer is always provided. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2020-07-07android: camera_device: Add buffers for each stream to RequestsKieran Bingham
Construct a FrameBuffer for every buffer given in the camera3Request and add it to the libcamera Request on the appropriate stream. The correct stream is obtained from the private data of the camera3_stream associated with the camera3_buffer. Comments regarding supporting only one buffer are now removed, and FrameBuffers have their lifetime tracked in the Camera3RequestDescriptor to ensure they are released when the Request is completed. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2020-07-06android: camera_device: Maintain a vector of CameraStreamKieran Bingham
Introduce a vector storing a CameraStream to track and maintain state between an Android stream (camera3_stream_t) and a libcamera Stream. Only the index of the libcamera stream is stored, to facilitate identifying the correct index for both the StreamConfiguration and Stream vectors. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2020-07-06android: camera_device: Create the Request and Camera3RequestDescriptor togetherKieran Bingham
Move the construction of the Request higher in the code flow so that multiple buffers and streams can be added where required. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2020-07-06android: camera_device: Simplify FrameBuffer construction from a buffer_handle_tKieran Bingham
Move the code which constructs a FrameBuffer from the Android buffer handle to it's own function to simplify the code flow and readability. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2020-07-06android: camera_device: Support multiple stream configurationsKieran Bingham
Create an initial Camera Configuration using an empty role set, and populate the StreamConfigurations manually from each of the streams given by the Android camera3_stream_configuration_t stream_list. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2020-07-06android: camera_device: Provide a toPixelFormat helperKieran Bingham
Rather than converting pixelformats through the map, and then dereferencing the iterator later, create a helper to explicitly return a PixelFormat type. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2020-07-06libcamera: camera: Allow unspecified roles for generateConfigurationKieran Bingham
Providing an empty set of roles is permitted to generate an empty configuration from the pipeline handlers. Overload the generateConfiguration() function such that not specifying a roles parameter will use an empty set, and return an empty configuration. Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2020-07-06libcamera: ipa: raspberrypi: Populate focus FoM from the ISP statisticsNaushir Patuck
Switch FocusStatus::num to unsigned int for convenience. Fill in libcamera::controls::FocusFoM with the average of the middle two regions (across a 4x3 grid) FoM statistics from the ISP. Signed-off-by: Naushir Patuck <naush@raspberrypi.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-07-06ipa: raspberrypi: Populate libcamera metadata after controller processNaushir Patuck
For control algorithms like focus, this is needed to return out the the current frame focus statistics. For other algorithms, there is no functional change. Signed-off-By: Naushir Patuck <naush@raspberrypi.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-07-06libcamera: controls: Add focus Figure of Merit (FoM) controlNaushir Patuck
Provide a control to allow the IPA to return a FoM to indicate how in-focus a scene is. Note, this is not to be used as a means to implement a focus algorithm by the application, rather an indication of how in-focus a scene is. Signed-off-by: Naushir Patuck <naush@raspberrypi.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-07-03utils: raspberrypi: ctt: json_pretty_print: Add newline at end of outputLaurent Pinchart
Make sure the output ends with a newline. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Tested-by: David Plowman <david.plowman@raspberrypi.com>
2020-07-03utils: raspberrypi: ctt: json_pretty_print: Avoid spaces at end of linesLaurent Pinchart
Avoid outputting spaces at end of lines by recording the need for a space and outputting it before the next character only if not a newline. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Tested-by: David Plowman <david.plowman@raspberrypi.com>
2020-07-03utils: raspberrypi: ctt: json_pretty_print: Collapse newlinesLaurent Pinchart
Simplify the newline skipping logic by simply collapsing newlines. If a newline has been output, all subsequent newlines will be skipped until the next non-newline character is output. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Tested-by: David Plowman <david.plowman@raspberrypi.com>
2020-07-03utils: raspberrypi: ctt: json_pretty_print: Fix indentation handlingLaurent Pinchart
Indentation is handled by outputting spaces right after outputting a newline character. That works in most cases, but would result in the input '{}' being printed as { } instead of { } Fix it by outputting the indentation before outputting the next character after a newline. The indentation value will be updated by then. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Tested-by: David Plowman <david.plowman@raspberrypi.com>
2020-07-03utils: raspberrypi: ctt: json_pretty_print: Add character write methodLaurent Pinchart
Add a write method to the JSONPrettyPrinter class to output a character. This will be used to handle state updates when outputting individual characters. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Tested-by: David Plowman <david.plowman@raspberrypi.com>
2020-07-03utils: raspberrypi: ctt: json_pretty_print: Skip all spacesLaurent Pinchart
Skip all white space characters, not just ' '. This makes a difference if the input JSON data is already formatted. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Tested-by: David Plowman <david.plowman@raspberrypi.com>
2020-07-03utils: raspberrypi: ctt: json_pretty_print: Make test output to stdoutLaurent Pinchart
The standalone test mode output to a file name "pretty.json". To make the test mode more versatile, output to stdout instead. The user can then decide how to use the output. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Tested-by: David Plowman <david.plowman@raspberrypi.com>
2020-07-03utils: raspberrypi: ctt: json_pretty_print: Make output file a class memberLaurent Pinchart
Instead of passing the output file to every method of the printer class, make it a class member. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Tested-by: David Plowman <david.plowman@raspberrypi.com>
2020-07-03utils: raspberrypi: ctt: json_pretty_print: Turn printer into a classLaurent Pinchart
Instead of passing a state dictionary to every method, turn the printer into a class and store the state internally. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Tested-by: David Plowman <david.plowman@raspberrypi.com>
2020-07-03utils: raspberrypi: ctt: json_pretty_print: Fix printer testLaurent Pinchart
The ctt_pretty_print_json.py file supports being run standalone to test the code. It however suffers from multiple issues: - The same input file name is hardcoded, and doesn't exist in the repository - The input file name is used instead of JSON data Fix both issues and make the input file selectable on the command line. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: David Plowman <david.plowman@raspberrypi.com> Tested-by: David Plowman <david.plowman@raspberrypi.com>
2020-07-03ipa: raspberrypi: Enable focus measure without recompileDavid Plowman
Previously, output of the focus measure could not be enabled without recompiling (because of the RPI_LOGGING_ENABLE macro). This uses the libcamera logging mechanism instead, so can be enabled/disabled at runtime. Signed-off-by: David Plowman <david.plowman@raspberrypi.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-07-03libcamera: ipu3: cio2: Do not proxy signalNiklas Söderlund
Do not proxy the signal in the CI2Device when there is no need for it, remove it. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-07-03libcamera: ipu3: Make it easier to read when a request may be completedNiklas Söderlund
It's confusing to read the code and understand that a request is only completed before being processed by the ImgU if it only contains a single RAW buffer. Add a boolean variable with a explanatory name to make this clearer, no functional change. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-07-03libcamera: raspberrypi: Document vc_sm_cma pointer sharing with IPANiklas Söderlund
Sharing a pointer with the IPA is fragile as it will not work with all IPC mechanisms. Document that it's a temporary workaround that should be reworked. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-07-01ipa/pipeline: rkisp1: Fix spellingAndrej Shadura
Fix a typo in the word "unknown". Suggested-by: IOhannes m zmölnig <umlaeute@debian.org> Signed-off-by: Andrej Shadura <andrewsh@debian.org> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
2020-06-29utils: raspberrypi: ctt: Fix pycodestyle W605Laurent Pinchart
W605 invalid escape sequence '\.' Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: David Plowman <david.plowman@raspberrypi.com>
2020-06-29libcamera: ipu3: cio2: Use Size::isNull()Niklas Söderlund
Use the Size::isNull() helper instead of using local code. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2020-06-29libcamera: geometry: Add isNull() function to Size classLaurent Pinchart
It's common for code to check if a size is null. Add a helper function to do so. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Umang Jain <email@uajain.com> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
2020-06-29libcamera: raspberrypi: Fail on unsupported stream roleJacopo Mondi
When an unsupported stream roles is requested to generateConfiguration(), the function shall fail instead of simply ignoring the request. Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-06-29libcamera: raspberrypi: Refuse invalid roles configurationJacopo Mondi
The generateConfiguration() implementation does not check if the requested list of roles can actually be satisfied. The camera API documentation prescribes the function shall fail in that case, instead of silently adjust the returned configuration. Fix this by implementing the same logic as the validate() function implements, as the pipeline handler supports one raw stream and up to two output streams. Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-06-29libcamera: ipu3: Fix wrong indentationJacopo Mondi
Fix wrong parameter indent in generateConfiguration() function implementation. Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-06-29libcamera: ipu3: Accept an empty roles listJacopo Mondi
The IPU3 pipeline handler that does not support receiving an empty list of roles at generateConfiguration() time. This contradicts the camera API which allows application to generate empty CameraConfiguration to be later manually filled. Fix this by returning an empty CameraConfiguration if the list of requested roles is empty. While at it, align the style with the other pipeline handlers. Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-06-29libcamera: ipu3: Improve error on multiple raw streams requestJacopo Mondi
Improve the error message emitted when multiple raw streams are requested. Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
2020-06-28libcamera: ipu3: imgu: Use unique_ptr for video and subdevicesNiklas Söderlund
Instead of manually deleting the video and subdevices in the destructor use std::unique_ptr. Suggested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-28libcamera: ipu3: imgu: Remove ImgUOutputNiklas Söderlund
The struct ImgUOutput now only contains one member that is in use, the video device. Remove the struct and use the video device directly instead. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-28libcamera: ipu3: Remove IPU3StreamNiklas Söderlund
The pipeline specific subclass of the pipeline is empty, remove it. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-28libcamera: ipu3: Remove the active flag from IPU3StreamNiklas Söderlund
The active_ flag is only used inside one function, remove the global flag and handle it inside the single function. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
2020-06-28libcamera: ipu3: Do not duplicate data in IPU3StreamNiklas Söderlund
Do not keep the duplicated ImgUDevice::ImgUOutput information in both the stream and camera data classes. Remove it from the stream and only access it from the camera data class. Which stream is which can instead be checked by comparing it to the known streams in camera data. This match how streams are checked in other parts of the code making the pipeline more coherent. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-28libcamera: ipu3: imgu: Use specific functions to configure each sinkNiklas Söderlund
When the IPU3 pipeline only provided streams to applications that came from the ImgU it made sense to have a generic function to configure all the different outputs. With the addition of the RAW stream this begins to be cumbersome to read and make sense of in the PipelineHandlerIPU3 code. Replace the generic function that takes a specific argument for which sink to configure with a specific function for each sink. This makes the code easier to follow as it's always clear which of the ImgU sinks are being configured without knowing the content of a generically named variable. It also paves the way for future improvements. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-28libcamera: ipu3: imgu: Mark things that are internal as privateNiklas Söderlund
Mark all variables and functions that are only used internally as private. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-28libcamera: ipu3: imgu: Do not cache indexNiklas Söderlund
The numerical index of the imgu is only used to create its name in string form. There is no need to keep it around after that, remove it. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-28libcamera: ipu3: imgu: Move the ImgUDevice class to separate filesNiklas Söderlund
In preparation of refactoring the IPU3 pipeline handler breakout the ImgUDevice into its own .cpp and .h file, no functional change. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-28libcamera: ipu3: Remove usage of IPU3CameraData from ImgUDeviceNiklas Söderlund
The IPU3CameraData argument to allocateBuffers() and freeBuffers() is no longer used and can be removed. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-28libcamera: ipu3: Always import buffers for ImgU sinksNiklas Söderlund
When the IPU3 pipeline was first developed sinks of the ImgU that where not active still needed to have buffers allocated to allow streaming to start. This is no longer true, it's enough that the sinks have imported buffers to allow streaming to start. As we already need to import buffers for stream that are active we can align the two cases and always import buffers. With this there is no longer a reason to store the allocated FrameBuffers to keep them alive and the vector tracking them can be removed. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-28libcamera: ipu3: Import instead of allocate statistic buffersNiklas Söderlund
Statistics buffers are not yet used by the IPU3 pipeline, they are never queued to the statistics video device or in any other way consumed. The kernel driver will however not allow video streaming to start if buffers are not either allocated or imported on the statistics video device. Instead of allocating the buffers wasting memory that is never used, import buffers. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-28libcamera: ipu3: Remove unused name_ filed from IPU3StreamNiklas Söderlund
The field is never used, remove it. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
2020-06-26libcamera: Summarize licensing terms in COPYING.rstLaurent Pinchart
Storing detailed licensing information in SPDX headers and in the DEP5 file gives precise information to handle license compliance, but lacks a high-level overview. Summmarize the licensing terms in a COPYING.rst file to facilitate understanding of the libcamera project licenses, and to clarify that closed-source third-party IPA modules are permitted. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Acked-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Tomasz Figa <tfiga@chromium.org>
2020-06-26libcamera: ipu3: Allow zero-copy RAW stream captureNiklas Söderlund
With the refactored CIO2 interface it's now easy to add zero-copy for buffers in the RAW stream. Use the internally allocated buffers inside the CIO2Device if no buffer for the RAW stream is provided by the application, or use the application-provided buffer if any. Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>