Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-or-later
/*
    V4L2 device support.
 
    Copyright (C) 2008  Hans Verkuil <hverkuil@xs4all.nl>
 
 */
 
#include <linux/types.h>
#include <linux/ioctl.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/videodev2.h>
#include <media/v4l2-device.h>
#include <media/v4l2-ctrls.h>
 
int v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev)
{
<------>if (v4l2_dev == NULL)
<------><------>return -EINVAL;
 
<------>INIT_LIST_HEAD(&v4l2_dev->subdevs);
<------>spin_lock_init(&v4l2_dev->lock);
<------>v4l2_prio_init(&v4l2_dev->prio);
<------>kref_init(&v4l2_dev->ref);
<------>get_device(dev);
<------>v4l2_dev->dev = dev;
<------>if (dev == NULL) {
<------><------>/* If dev == NULL, then name must be filled in by the caller */
<------><------>if (WARN_ON(!v4l2_dev->name[0]))
<------><------><------>return -EINVAL;
<------><------>return 0;
<------>}
 
<------>/* Set name to driver name + device name if it is empty. */
<------>if (!v4l2_dev->name[0])
<------><------>snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s %s",
<------><------><------>dev->driver->name, dev_name(dev));
<------>if (!dev_get_drvdata(dev))
<------><------>dev_set_drvdata(dev, v4l2_dev);
<------>return 0;
}
EXPORT_SYMBOL_GPL(v4l2_device_register);
 
static void v4l2_device_release(struct kref *ref)
{
<------>struct v4l2_device *v4l2_dev =
<------><------>container_of(ref, struct v4l2_device, ref);
 
<------>if (v4l2_dev->release)
<------><------>v4l2_dev->release(v4l2_dev);
}
 
int v4l2_device_put(struct v4l2_device *v4l2_dev)
{
<------>return kref_put(&v4l2_dev->ref, v4l2_device_release);
}
EXPORT_SYMBOL_GPL(v4l2_device_put);
 
int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
<------><------><------><------><------><------>atomic_t *instance)
{
<------>int num = atomic_inc_return(instance) - 1;
<------>int len = strlen(basename);
 
<------>if (basename[len - 1] >= '0' && basename[len - 1] <= '9')
<------><------>snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
<------><------><------><------>"%s-%d", basename, num);
<------>else
<------><------>snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
<------><------><------><------>"%s%d", basename, num);
<------>return num;
}
EXPORT_SYMBOL_GPL(v4l2_device_set_name);
 
void v4l2_device_disconnect(struct v4l2_device *v4l2_dev)
{
<------>if (v4l2_dev->dev == NULL)
<------><------>return;
 
<------>if (dev_get_drvdata(v4l2_dev->dev) == v4l2_dev)
<------><------>dev_set_drvdata(v4l2_dev->dev, NULL);
<------>put_device(v4l2_dev->dev);
<------>v4l2_dev->dev = NULL;
}
EXPORT_SYMBOL_GPL(v4l2_device_disconnect);
 
void v4l2_device_unregister(struct v4l2_device *v4l2_dev)
{
<------>struct v4l2_subdev *sd, *next;
 
<------>/* Just return if v4l2_dev is NULL or if it was already
<------> * unregistered before. */
<------>if (v4l2_dev == NULL || !v4l2_dev->name[0])
<------><------>return;
<------>v4l2_device_disconnect(v4l2_dev);
 
<------>/* Unregister subdevs */
<------>list_for_each_entry_safe(sd, next, &v4l2_dev->subdevs, list) {
<------><------>v4l2_device_unregister_subdev(sd);
<------><------>if (sd->flags & V4L2_SUBDEV_FL_IS_I2C)
<------><------><------>v4l2_i2c_subdev_unregister(sd);
<------><------>else if (sd->flags & V4L2_SUBDEV_FL_IS_SPI)
<------><------><------>v4l2_spi_subdev_unregister(sd);
<------>}
<------>/* Mark as unregistered, thus preventing duplicate unregistrations */
<------>v4l2_dev->name[0] = '\0';
}
EXPORT_SYMBOL_GPL(v4l2_device_unregister);
 
int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
<------><------><------><------>struct v4l2_subdev *sd)
{
<------>int err;
 
<------>/* Check for valid input */
<------>if (!v4l2_dev || !sd || sd->v4l2_dev || !sd->name[0])
<------><------>return -EINVAL;
 
<------>/*
<------> * The reason to acquire the module here is to avoid unloading
<------> * a module of sub-device which is registered to a media
<------> * device. To make it possible to unload modules for media
<------> * devices that also register sub-devices, do not
<------> * try_module_get() such sub-device owners.
<------> */
<------>sd->owner_v4l2_dev = v4l2_dev->dev && v4l2_dev->dev->driver &&
<------><------>sd->owner == v4l2_dev->dev->driver->owner;
 
<------>if (!sd->owner_v4l2_dev && !try_module_get(sd->owner))
<------><------>return -ENODEV;
 
<------>sd->v4l2_dev = v4l2_dev;
<------>/* This just returns 0 if either of the two args is NULL */
<------>err = v4l2_ctrl_add_handler(v4l2_dev->ctrl_handler, sd->ctrl_handler,
<------><------><------><------>    NULL, true);
<------>if (err)
<------><------>goto error_module;
 
#if defined(CONFIG_MEDIA_CONTROLLER)
<------>/* Register the entity. */
<------>if (v4l2_dev->mdev) {
<------><------>err = media_device_register_entity(v4l2_dev->mdev, &sd->entity);
<------><------>if (err < 0)
<------><------><------>goto error_module;
<------>}
#endif
 
<------>if (sd->internal_ops && sd->internal_ops->registered) {
<------><------>err = sd->internal_ops->registered(sd);
<------><------>if (err)
<------><------><------>goto error_unregister;
<------>}
 
<------>spin_lock(&v4l2_dev->lock);
<------>list_add_tail(&sd->list, &v4l2_dev->subdevs);
<------>spin_unlock(&v4l2_dev->lock);
 
<------>return 0;
 
error_unregister:
#if defined(CONFIG_MEDIA_CONTROLLER)
<------>media_device_unregister_entity(&sd->entity);
#endif
error_module:
<------>if (!sd->owner_v4l2_dev)
<------><------>module_put(sd->owner);
<------>sd->v4l2_dev = NULL;
<------>return err;
}
EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);
 
static void v4l2_subdev_release(struct v4l2_subdev *sd)
{
<------>struct module *owner = !sd->owner_v4l2_dev ? sd->owner : NULL;
 
<------>if (sd->internal_ops && sd->internal_ops->release)
<------><------>sd->internal_ops->release(sd);
<------>sd->devnode = NULL;
<------>module_put(owner);
}
 
static void v4l2_device_release_subdev_node(struct video_device *vdev)
{
<------>v4l2_subdev_release(video_get_drvdata(vdev));
<------>kfree(vdev);
}
 
int __v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev,
<------><------><------><------><------>bool read_only)
{
<------>struct video_device *vdev;
<------>struct v4l2_subdev *sd;
<------>int err;
 
<------>/* Register a device node for every subdev marked with the
<------> * V4L2_SUBDEV_FL_HAS_DEVNODE flag.
<------> */
<------>list_for_each_entry(sd, &v4l2_dev->subdevs, list) {
<------><------>if (!(sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE))
<------><------><------>continue;
 
<------><------>if (sd->devnode)
<------><------><------>continue;
 
<------><------>vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
<------><------>if (!vdev) {
<------><------><------>err = -ENOMEM;
<------><------><------>goto clean_up;
<------><------>}
 
<------><------>video_set_drvdata(vdev, sd);
<------><------>strscpy(vdev->name, sd->name, sizeof(vdev->name));
<------><------>vdev->dev_parent = sd->dev;
<------><------>vdev->v4l2_dev = v4l2_dev;
<------><------>vdev->fops = &v4l2_subdev_fops;
<------><------>vdev->release = v4l2_device_release_subdev_node;
<------><------>vdev->ctrl_handler = sd->ctrl_handler;
<------><------>if (read_only)
<------><------><------>set_bit(V4L2_FL_SUBDEV_RO_DEVNODE, &vdev->flags);
<------><------>err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1,
<------><------><------><------><------>      sd->owner);
<------><------>if (err < 0) {
<------><------><------>kfree(vdev);
<------><------><------>goto clean_up;
<------><------>}
<------><------>sd->devnode = vdev;
#if defined(CONFIG_MEDIA_CONTROLLER)
<------><------>sd->entity.info.dev.major = VIDEO_MAJOR;
<------><------>sd->entity.info.dev.minor = vdev->minor;
 
<------><------>/* Interface is created by __video_register_device() */
<------><------>if (vdev->v4l2_dev->mdev) {
<------><------><------>struct media_link *link;
 
<------><------><------>link = media_create_intf_link(&sd->entity,
<------><------><------><------><------><------>      &vdev->intf_devnode->intf,
<------><------><------><------><------><------>      MEDIA_LNK_FL_ENABLED |
<------><------><------><------><------><------>      MEDIA_LNK_FL_IMMUTABLE);
<------><------><------>if (!link) {
<------><------><------><------>err = -ENOMEM;
<------><------><------><------>goto clean_up;
<------><------><------>}
<------><------>}
#endif
<------>}
<------>return 0;
 
clean_up:
<------>list_for_each_entry(sd, &v4l2_dev->subdevs, list) {
<------><------>if (!sd->devnode)
<------><------><------>break;
<------><------>video_unregister_device(sd->devnode);
<------>}
 
<------>return err;
}
EXPORT_SYMBOL_GPL(__v4l2_device_register_subdev_nodes);
 
void v4l2_device_unregister_subdev(struct v4l2_subdev *sd)
{
<------>struct v4l2_device *v4l2_dev;
 
<------>/* return if it isn't registered */
<------>if (sd == NULL || sd->v4l2_dev == NULL)
<------><------>return;
 
<------>v4l2_dev = sd->v4l2_dev;
 
<------>spin_lock(&v4l2_dev->lock);
<------>list_del(&sd->list);
<------>spin_unlock(&v4l2_dev->lock);
 
<------>if (sd->internal_ops && sd->internal_ops->unregistered)
<------><------>sd->internal_ops->unregistered(sd);
<------>sd->v4l2_dev = NULL;
 
#if defined(CONFIG_MEDIA_CONTROLLER)
<------>if (v4l2_dev->mdev) {
<------><------>/*
<------><------> * No need to explicitly remove links, as both pads and
<------><------> * links are removed by the function below, in the right order
<------><------> */
<------><------>media_device_unregister_entity(&sd->entity);
<------>}
#endif
<------>if (sd->devnode)
<------><------>video_unregister_device(sd->devnode);
<------>else
<------><------>v4l2_subdev_release(sd);
}
EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);