The V4L2PixelFormat class describes the pixel format of a V4L2 buffer.
It wraps the V4L2 numerical FourCC, and shall be used in all APIs that
deal with V4L2 pixel formats. Its purpose is to prevent unintentional
confusion of V4L2 and DRM FourCCs in code by catching implicit
conversion attempts at compile time.
The constructor taking a V4L2 FourCC integer value will be made explicit
in a further commit to minimize the size of this change and keep it
reviewable.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Add a new exportBuffers() function that only performs buffer allocation
and export, but leaves the V4L2 buffer queue unallocated on return. This
function will be used to simplify buffer allocation for pipeline
handlers. This is made possible by the V4L2 buffer orphaning feature
introduced in Linux v5.0, so add a version check to catch and report
issues early.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Move the buffer creation code out of allocateBuffers() to a
createBuffers() function. This prepare for the rework of buffer export
and will avoid code duplication.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
To prepare for the rework of buffer export, pass the memory type
explicitly to the V4L2VideoDevice::reqbufs() function.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
To prepare for the rework of buffer allocation that will differentiate
export and allocation, rename exportBuffers() to allocateBuffers().
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
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>
The std::atomic_uint64_t specialization was missing from C++14, and only
added to C++17 (see LWG 2441). It was treated as a Defect Report and
backported to earlier C++ standards by gcc and clang, but is missing
from libstdc++ shipped with gcc 5 and gcc 6. Fix the compilation error
by using std::atomic<uint64_t> instead.
Fixes: 4e0d1eca10 ("libcamera: V4L2BufferCache: Improve cache eviction strategy")
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
The strategy used to find a free cache entry in the first implementation
was not the smartest, it picked the first free entry. This lead to
unwanted performance issues as the cache was not used as good as it
could for imported buffers.
Improve this by adding a last usage sequence number to the cache entries
and change the eviction strategy to use the oldest free entry instead of
the first one it finds.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
The Buffer interface is no longer in use and can be removed. While doing
so clean up the two odd names (dequeueFrameBuffer() and
queuedFrameBuffers_) that had to be used when adding the FrameBuffer
interface.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Add a new interface in parallel with the existing Buffer implementation
to also support FrameBuffer. The reason it's added in parallel is to aid
in the migration from Buffer to FrameBuffer throughout libcamera. With
this change discrete parts of libcamera can be migrated and tested
independently.
As the new interface is added in parallel there are some oddities in
this change which will be undone in a follow up patch once libcamera
have migrated away from the Buffer interface.
- There is a nasty hack in V4L2VideoDevice::bufferAvailable(). It is
needed to allow both interfaces to exist and function at the same
time. The idea is if buffers are allocated using the FrameBuffer
interface V4L2VideoDevice::cache_ is set and we know to call the
FrameBuffer 'buffer ready' signal, and likewise if it's not to call
the Buffer variant.
- There is some code duplication between the two interfaces as they aim
to solve the same thing in slightly different ways. As all Buffer
related code is soon to be removed no effort to create code sharing
between them have been made.
- Some function and variables which can't be distinguished by their
argument types have been given a frameBuffer prefix instead of a
buffer prefix. They are clearly documented in the code and will be
renamed to the correct buffer prefix when the Buffer interface is
removed.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
In preparation for the FrameBuffer interface add a class that will deal
with keeping the cache between dmabuf file descriptors and V4L2 video
device buffer indexes.
This initial implementation ensures that no hot association is lost
while its eviction strategy could be improved in the future.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
The part in createPlane() that exports a dma buffer from a video device
will be used directly by the FrameBuffer interface. Break it out to a
separate function.
Signed-off-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
In preparation for switching PixelFormat to DRM pixel formats, add
helper methods to the V4L2VideoDevice class to translate between DRM
pixel formats and V4L2 pixel formats.
More work is needed to properly support the V4L2 multi-planar
(NV[0-9]*M) formats.
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
M2M devices using MPLANE API will set the V4L2_CAP_VIDEO_M2M_MPLANE
capability flag.
Ensure that this is matched when checking for Multiplanar capabilities.
Fixes: 4f7625cca7 ("libcamera: v4l2_videodevice: Support M2M devices")
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>
V4L2 M2M devices represent a V4L2Device with two queues: One output, and
one capture on a single device node.
Represent this by instantiating a V4L2VideoDevice for each queue type,
and preparing each device for its queue.
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
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>
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>
Group together operations to enumerate formats and operations to handle
memory handling, alternating public and private operations but
respecting the ordering within each group. Cosmetic change only.
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
The V4L2 devices and subdevices share a few common operations,like
opening and closing a device node, and perform IOCTLs on the device.
With the forthcoming introduction of support for V4L2 controls, the
quantity of shared code will increase, as the control support
implementation is identical for the two derived classes.
To maximize code re-use and avoid duplications, provide a V4L2Device
base class which groups the common operations and members.
The newly introduced base class provides methods to open/close a device
node, access the file descriptor, and perform IOCTLs on the device.
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Laurent Pinchart
Niklas Söderlund
Naushir PatuckandLaurent Pinchart
Jacopo MondiandLaurent Pinchart
Kieran Bingham