converter_v4l2_m2m.h

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/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2020, Laurent Pinchart
 * Copyright 2022 NXP
 *
 * V4l2 M2M Format converter interface
 */

#pragma once

#include <functional>
#include <map>
#include <memory>
#include <string>
#include <tuple>
#include <vector>

#include <libcamera/base/log.h>
#include <libcamera/base/signal.h>

#include <libcamera/pixel_format.h>

#include "libcamera/internal/converter.h"

namespace libcamera {

class FrameBuffer;
class MediaDevice;
class Size;
class SizeRange;
class Stream;
struct StreamConfiguration;
class V4L2M2MDevice;

class V4L2M2MConverter : public Converter
{
public:
    V4L2M2MConverter(MediaDevice *media);

    int loadConfiguration([[maybe_unused]] const std::string &filename) { return 0; }
    bool isValid() const { return m2m_ != nullptr; }

    std::vector<PixelFormat> formats(PixelFormat input);
    SizeRange sizes(const Size &input);

    std::tuple<unsigned int, unsigned int>
    strideAndFrameSize(const PixelFormat &pixelFormat, const Size &size);

    int configure(const StreamConfiguration &inputCfg,
              const std::vector<std::reference_wrapper<StreamConfiguration>> &outputCfg);
    int exportBuffers(const Stream *stream, unsigned int count,
              std::vector<std::unique_ptr<FrameBuffer>> *buffers);

    int start();
    void stop();

    int queueBuffers(FrameBuffer *input,
             const std::map<const Stream *, FrameBuffer *> &outputs);

private:
    class V4L2M2MStream : protected Loggable
    {
    public:
        V4L2M2MStream(V4L2M2MConverter *converter, const Stream *stream);

        bool isValid() const { return m2m_ != nullptr; }

        int configure(const StreamConfiguration &inputCfg,
                  const StreamConfiguration &outputCfg);
        int exportBuffers(unsigned int count,
                  std::vector<std::unique_ptr<FrameBuffer>> *buffers);

        int start();
        void stop();

        int queueBuffers(FrameBuffer *input, FrameBuffer *output);

    protected:
        std::string logPrefix() const override;

    private:
        void captureBufferReady(FrameBuffer *buffer);
        void outputBufferReady(FrameBuffer *buffer);

        V4L2M2MConverter *converter_;
        const Stream *stream_;
        std::unique_ptr<V4L2M2MDevice> m2m_;

        unsigned int inputBufferCount_;
        unsigned int outputBufferCount_;
    };

    std::unique_ptr<V4L2M2MDevice> m2m_;

    std::map<const Stream *, std::unique_ptr<V4L2M2MStream>> streams_;
    std::map<FrameBuffer *, unsigned int> queue_;
};

} /* namespace libcamera */