/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2019, Google Inc.
 *
 * v4l2_device.cpp - Common base for V4L2 video devices and subdevices
 */

#include "libcamera/internal/v4l2_device.h"

#include <fcntl.h>
#include <iomanip>
#include <limits.h>
#include <map>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/syscall.h>
#include <unistd.h>
#include <vector>

#include <linux/v4l2-mediabus.h>

#include <libcamera/base/event_notifier.h>
#include <libcamera/base/log.h>
#include <libcamera/base/utils.h>

#include "libcamera/internal/formats.h"
#include "libcamera/internal/sysfs.h"

/**
 * \file v4l2_device.h
 * \brief Common base for V4L2 devices and subdevices
 */

namespace libcamera {

LOG_DEFINE_CATEGORY(V4L2)

/**
 * \class V4L2Device
 * \brief Base class for V4L2VideoDevice and V4L2Subdevice
 *
 * The V4L2Device class groups together the functions and fields common to
 * both the V4L2VideoDevice and V4L2Subdevice classes, and provides a base
 * class with functions to open and close the device node associated with the
 * device and to perform IOCTL system calls on it.
 *
 * The V4L2Device class cannot be instantiated directly, as its constructor
 * is protected. Users should instead create instances of one the derived
 * classes to model either a V4L2 video device or a V4L2 subdevice.
 */