Age | Commit message (Collapse) | Author |
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These formats can be helpful when downstream applications or libraries
support them natively (avoiding a costly conversion).
Signed-off-by: David Plowman <david.plowman@raspberrypi.com>
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>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
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Some applications (eg. Firefox, Google Chrome, Skype) use open64,
openat64, and mmap64 instead of their non-64 versions that we currently
intercept. Intercept these calls as well. _LARGEFILE64_SOURCE needs to
be set so that the 64-bit symbols are available and not synonymous to
the non-64-bit versions on 64-bit systems.
Also, since we set _FILE_OFFSET_BITS to 32 to force the various open and
mmap symbols that we export to not be the 64-bit versions, our dlsym to
get the original open and mmap calls will not automatically be converted
to their 64-bit versions. Since we intercept both 32-bit and 64-bit
versions of open and mmap, we should be using the 64-bit version to
service both. Fetch the 64-bit versions of openat and mmap directly.
musl defines the 64-bit symbols as macros that are equivalent to the
non-64-bit symbols, so we put compile guards that check if the 64-bit
symbols are defined.
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> # Compile with musl
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
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Use the new pixel format constants to replace usage of macros from
drm_fourcc.h.
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>
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The return value of the write to the eventfd (to signal POLLIN) from
V4L2Camera and the read from the eventfd (to clear POLLIN) from
V4L2CameraProxy was ignored. Check the return value, and print an error
message.
Reported-by: Coverity CID=290743
Reported-by: Coverity CID=290744
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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Add an entry for MJPEG in V4L2CameraProxy's PixelFormatInfo list to
allow proper calculation of sizeimage for MJPEG, such that the
parameters to mmap can align properly instead of failing. This allows
MJPEG to be used in the V4L2 compatibility layer.
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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The NV24 pixelFormatInfo table entry defines an incorrect horizontal
sub-sampling.
Update to the correct value.
Fixes: 29c5508075c1 ("v4l2: camera_proxy: Create format info array")
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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The V4L2 compatibility layer keeps track of the index of the next buffer
to be dequeued, to handle VIDIOC_DQBUF. This index is set to 0 on
startup and incremented (modulo #frames), and is otherwise never reset.
This means that if the last handled frame index is not #frames-1, and
the stream is restarted without restarting libcamera and the V4L2
compatilibity layer, the buffer index number won't match with the
libcamera buffer index number, causing a segfault. Fix this by resetting
the current buffer index to zero on VIDIOC_STREAMON.
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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To support polling, we need to be able to signal when data is
available to be read (POLLIN), as well as events (POLLPRI). Add the
necessary calls to eventfd to allow signaling POLLIN. We signal POLLIN
by writing writing to the eventfd, and clear it by reading from the
eventfd, upon VIDIOC_DQBUF.
Note that eventfd does not support signaling POLLPRI, so we don't yet
support V4L2 events.
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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If VIDIOC_REQBUFS returns -EINVAL, it signals to the application that
the requested buffer or memory type is not supported. If we return
-EINVAL due to a zero sizeimage, then the application will think that we
don't support a memory type that we actually do. We cannot error on a
zero sizeimage, because reqbufs could be called merely to probe what IO
methods we support; qv4l2, for example, called reqbufs once with userptr
and once more with mmap, both times with count=1.
On the other hand, sizeimage will be zero for formats whose size we
don't know how to calculate, such as MJPEG. If we try to stream such
formats anyway, we will get a floating point exception and crash. Issue
a warning for now, and don't return -EINVAL, so that we can continue
operation.
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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We use a semaphore to atomically keep track of how many buffers are
available for dequeueing. The check for how to acquire the semaphore was
incorrect, leading to a double acquire upon a successful nonblocking
acquire. Fix this.
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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VIDIOC_ENUM_FMT is meant to return -EINVAL if the requested index is out
of bounds. This bounds is obtained from the libcamera Camera's list of
formats. The bounds check for this list was incorrect; fix it.
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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The V4L2 compatibility layer is licensed under the GPL. It is compiled
as a binary separate from libcamera.so, and is loaded into the address
space of processes through LD_PRELOAD to intercept calls to the C
library.
It is our understanding and intent that the GPL license doesn't
propagate to the binaries whose calls are intercepted, considering those
binaries are not derivative work of the V4L2 compatibility layer and are
not designed to be linked to the V4L2 compatibility layer. There is
however a possibly grey area if binaries are packaged with a shell
script wrapper that loads the V4L2 compatibility layer. This could lead
to license-related issues if such packaging is performed by Linux
distributions or system integrators.
To clarify the intent and lift the doubts, relicense the V4L2
compatibility layer under the LGPL. The V4L2 compatibility layer code
itself still benefits from the license protection, while its usage with
third-party binaries is clearly allowed as intended.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Jacopo Mondi <jacopo@jmondi.org>
Acked-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Acked-by: Paul Elder <paul.elder@ideasonboard.com>
Acked-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Acked-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
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The libcamera internal headers are located in src/libcamera/include/.
The directory is added to the compiler headers search path with a meson
include_directories() directive, and internal headers are included with
(e.g. for the internal semaphore.h header)
#include "semaphore.h"
All was well, until libcxx decided to implement the C++20
synchronization library. The __threading_support header gained a
#include <semaphore.h>
to include the pthread's semaphore support. As include_directories()
adds src/libcamera/include/ to the compiler search path with -I, the
internal semaphore.h is included instead of the pthread version.
Needless to say, the compiler isn't happy.
Three options have been considered to fix this issue:
- Use -iquote instead of -I. The -iquote option instructs gcc to only
consider the header search path for headers included with the ""
version. Meson unfortunately doesn't support this option.
- Rename the internal semaphore.h header. This was deemed to be the
beginning of a long whack-a-mole game, where namespace clashes with
system libraries would appear over time (possibly dependent on
particular system configurations) and would need to be constantly
fixed.
- Move the internal headers to another directory to create a unique
namespace through path components. This causes lots of churn in all
the existing source files through the all project.
The first option would be best, but isn't available to us due to missing
support in meson. Even if -iquote support was added, we would need to
fix the problem before a new version of meson containing the required
support would be released.
The third option is thus the only practical solution available. Bite the
bullet, and do it, moving headers to include/libcamera/internal/.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Jacopo Mondi <jacopo@jmondi.org>
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In an attempt to clarify the license terms of all files in the libcamera
project, the build system files deserve particular attention. While they
describe how the binaries are created, they are not themselves
transformed into any part of binary distributions of the software, and
thus don't influence the copyright on the binary packages. They are
however subject to copyright, and thus influence the distribution terms
of the source packages.
Most of the meson.build files would not meet the threshold of
originality criteria required for copyright protection. Some of the more
complex meson.build files may be eligible for copyright protection. To
avoid any ambiguity and uncertainty, state our intent to not assert
copyrights on the build system files by putting them in the public
domain with the CC0-1.0 license.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Acked-by: Giulio Benetti <giulio.benetti@micronovasrl.com>
Acked-by: Jacopo Mondi <jacopo@jmondi.org>
Acked-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Acked-by: Naushir Patuck <naush@raspberrypi.com>
Acked-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Acked-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Acked-by: Paul Elder <paul.elder@ideasonboard.com>
Acked-by: Show Liu <show.liu@linaro.org>
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The Camera class currently requires the allocator to have no allocated
buffer before the camera is reconfigured, and the allocator to be
destroyed before the camera is released. There's no basis for these
restrictions anymore, remove them.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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const reference
PixelFormat was previously an alias for unsigned int but is now a
class. Make all functions taking PixelFormat do so as a const reference.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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To achieve the goal of preventing unwanted conversion between a DRM and
a V4L2 FourCC, make the PixelFormat constructor that takes an integer
value explicit. All users of pixel formats flagged by the compiler
are fixed.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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Create a class to represent a pixel format. This is done to add support
for modifiers for the formats. So far no modifiers are added by any
pipeline handler, all plumbing to deal with them is however in place.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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Instead of having to include linux/drm_fourcc.h everywhere a DRM FourCC
is used in conjunction with PixelFormat include the header directly in
pixelformats.h.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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When compiling for ARM and uClibc, gcc-8.3.0 complains about comparison
of integer expressions of different signedness:
../../src/v4l2/v4l2_camera_proxy.cpp: In member function ‘void* V4L2CameraProxy::mmap(void*, size_t, int, int, off_t)’:
../../src/v4l2/v4l2_camera_proxy.cpp:88:25: error: comparison of integer expressions of different signedness: ‘unsigned int’ and ‘off_t’ {aka ‘long int’} [-Werror=sign-compare]
if (index * sizeimage_ != offset || length != sizeimage_) {
~~~~~~~~~~~~~~~~~~~^~~~~~~~~
Fix the compilation error with a cast.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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The v4l2-compat shared library is declared as depending on
libcamera_deps. This is not correct, as libcamera_deps contains the
dependencies of libcamera itself. The correct dependency for users of
libcamera is libcamera_dep.
Fixing this allows dropping libcamera_includes from the list of includes
required by v4l2-compat, and libcamera from the link_with list, as they
are already contained in libcamera_dep. We however need to add an
explicit dependency on libdl which was previously provided by
libcamera_deps.
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>
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Now that libcamera creates threads internally and doesn't rely on an
application-provided event loop, remove the thread from the V4L2
compatibility layer. The split between the V4L2CameraProxy and
V4L2Camera classes is still kept to separate the V4L2 adaptation from
camera operation. This may be further refactored later.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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This capability tells the application that mmap() is supported. GStreamer
would return an error saying there there is no input/output method supported
by this device otherwise. This was tested with:
LD_PRELOAD=$(pwd)/build/src/v4l2/v4l2-compat.so GST_DEBUG="v4l2*:7" gst-launch-1.0 v4l2src ! videoconvert ! autovideosink
With this patch, GStreamer will reach playing state. It then blocks waiting on
poll() which is not implemented yet on our side.
Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
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Now that we're using C++-14, drop utils::make_unique for
std::make_unique.
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>
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With the FrameBuffer rework completed there is no reason to keep the
camera prepared state around as buffer allocations are now decoupled
from the camera state. Remove the camera state simplifying the API.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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Switch to the FrameBuffer interface where all buffers are treated as
external buffers and are allocated outside the camera. Applications
allocating buffers using libcamera are switched to use the
FrameBufferAllocator helper.
Follow-up changes to this one will finalize the transition to the new
FrameBuffer interface by removing code that is left unused after this
change.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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Move the metadata retrieved when dequeuing a V4L2 buffer into a
FrameMetadata object. This is done as a step to migrate to the
FrameBuffer interface as the functions added to Buffer around
FrameMetadata match the ones in FrameBuffer.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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In the FrameBuffer interface the stream will not be available from the
buffer object as the buffer might be allocated externally. The
application needs to explicitly state which stream the buffer is being
added for to the request.
Extend the addBuffer() function to get this information explicitly from
the caller.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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It is not libcamera's responsibility to handle memory mappings. Switch
from the soon to be removed Plane class which deals with memory
mappings to FrameBuffer::Plane which just describes it. This makes the
transition to the full FrameBuffer easier.
As the full FrameBuffer interface has not yet spread to all parts of
libcamera core it is hard to create efficient caching of memory mappings
in the qcam application. This will be fixed in a later patch, for now
the dmabuf is mapped and unmapped each time it is seen by the
application.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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The V4L2Camera::getBufferFd() method doesn't need to run in the camera
thread. Call it directly.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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In the upcoming FrameBuffer API the memory mapping of buffers will be
left to the user of the FrameBuffer objects. Prepare the V4L2
compatibility layer to this upcoming change to ease conversion to the
new API.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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With the upcoming FrameBuffer API a new library wide FrameMetadata
object will be added which will replace the specific implementation in
the V4L2 compatibility layer.
Avoid name collisions while the new FrameBuffer API is added by renaming
the V4L2 compatibility layer specific implementation until it can be
replaced with the library wide implementation.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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Refactoring of the camera_proxy have left the 'ret' variable undeclared,
declare it.
../../src/v4l2/v4l2_camera_proxy.cpp:273:2: error: use of undeclared identifier 'ret'
ret = vcam_->invokeMethod(&V4L2Camera::configure,
^
../../src/v4l2/v4l2_camera_proxy.cpp:278:6: error: use of undeclared identifier 'ret'
if (ret < 0)
Fixes: fce110c6d961c3bb ("v4l2: camera_proxy: Break out try_fmt")
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Acked-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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Most of the ioctl handlers in the V4L2CameraProxy class have an empty
line between the tracing printouts and the immediately following buffer
type validation. Align the two occasions where such an empty line is missing
with the others.
Cosmetic change only.
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
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Calling vidioc_s_fmt() calls vidioc_try_fmt() duplicating prinouts.
Breakout try format procedure and call it from both functions.
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
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The set pixelformat field of struct v4l2_pix_format structure was
wrongly converted to PixelFormat by calling v4l2ToDrm(), with an already
converted 'format' argument.
Fix this by calling the right drmToV4l2() conversion function.
Fixes: 0ce8f2390b52 ("v4l2: v4l2_compat: Add V4L2 compatibility layer")
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
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Commit 29c5508075c1 ("v4l2: camera_proxy: Create format info array")
introduced usage of the std::array template class, but didn't include
the corresponding header. This may cause a compilation breakage in the
future if the indirect include of <array> disappears due to unrelated
changes. Fix it.
Fixed: 29c5508075c1 ("v4l2: camera_proxy: Create format info array")
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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Create a PixelFormatInfo structure to store information about a format,
and add a global array of format info for all the formats currently
supported. Move the format helpers to use the information from the
array.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
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To clarify code, adopt the following rules for format helpers:
- All variables representing V4L2 pixel formats shall use uint32_t
- All variables representing DRM pixel formats shall use PixelFormat
- Functions returning positive values only shall not have a signed
return type
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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Create a new FileOperations structure to hold all the dynamically-loaded
C library file operations. The file operations are now exposed publicly,
to prepare for usage of mmap in the V4L2CameraProxy.
A new template helper function is added to retrieve a symbol with
dlsym() with proper casting to simplify the V4L2CompatManager
constructor.
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>
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Now that Object::invokeMethod() supports returning a value, use it and
drop the return value method argument.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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The __open_2() and __openat_2() functions are defined by glibc as taking
2 and 3 arguments respectively, with variadic arguments for the file
mode as open() and openat() do. The V4L2 compatibility layer defines
them as aliases for open() and openat(), which results in compilation
failures with gcc:
../../src/v4l2/v4l2_compat.cpp: In function ‘int __openat_2(int, const char*, int)’:
../../src/v4l2/v4l2_compat.cpp:58:14: error: invalid conversion from ‘int’ to ‘const char*’ [-fpermissive]
58 | return open(dirfd, path, oflag);
| ^~~~~
| |
| int
../../src/v4l2/v4l2_compat.cpp:31:39: note: initializing argument 1 of ‘int open(const char*, int, ...)’
31 | LIBCAMERA_PUBLIC int open(const char *path, int oflag, ...)
| ~~~~~~~~~~~~^~~~
../../src/v4l2/v4l2_compat.cpp:58:21: error: invalid conversion from ‘const char*’ to ‘int’ [-fpermissive]
58 | return open(dirfd, path, oflag);
| ^~~~
| |
| const char*
../../src/v4l2/v4l2_compat.cpp:31:49: note: initializing argument 2 of ‘int open(const char*, int, ...)’
31 | LIBCAMERA_PUBLIC int open(const char *path, int oflag, ...)
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Fix this by defining the two functions as wrappers around open() and
openat() without variadic arguments.
Fixes: 0ce8f2390b52 ("v4l2: v4l2_compat: Add V4L2 compatibility layer")
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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Add libcamera V4L2 compatibility layer.
This initial implementation supports the minimal set of V4L2 operations,
which allows getting, setting, and enumerating formats, and streaming
frames from a video device. Some data about the wrapped V4L2 video
device are hardcoded.
Add a build option named 'v4l2' and adjust the build system to
selectively compile the V4L2 compatibility layer.
For now we match the V4L2 device node to a libcamera camera based on a
devnum that a pipeline handler may optionally map to a libcamera
camera.
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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