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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/media/v4l2-core/v4l2-device.c | |
parent | Initial commit. (diff) | |
download | linux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip |
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/media/v4l2-core/v4l2-device.c')
-rw-r--r-- | drivers/media/v4l2-core/v4l2-device.c | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/v4l2-device.c b/drivers/media/v4l2-core/v4l2-device.c new file mode 100644 index 000000000..3940e55c7 --- /dev/null +++ b/drivers/media/v4l2-core/v4l2-device.c @@ -0,0 +1,323 @@ +/* + V4L2 device support. + + Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/types.h> +#include <linux/ioctl.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/slab.h> +#if defined(CONFIG_SPI) +#include <linux/spi/spi.h> +#endif +#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 IS_ENABLED(CONFIG_I2C) + if (sd->flags & V4L2_SUBDEV_FL_IS_I2C) { + struct i2c_client *client = v4l2_get_subdevdata(sd); + + /* + * We need to unregister the i2c client + * explicitly. We cannot rely on + * i2c_del_adapter to always unregister + * clients for us, since if the i2c bus is a + * platform bus, then it is never deleted. + * + * Device tree or ACPI based devices must not + * be unregistered as they have not been + * registered by us, and would not be + * re-created by just probing the V4L2 driver. + */ + if (client && + !client->dev.of_node && !client->dev.fwnode) + i2c_unregister_device(client); + continue; + } +#endif +#if defined(CONFIG_SPI) + if (sd->flags & V4L2_SUBDEV_FL_IS_SPI) { + struct spi_device *spi = v4l2_get_subdevdata(sd); + + if (spi && !spi->dev.of_node && !spi->dev.fwnode) + spi_unregister_device(spi); + continue; + } +#endif + } + /* 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) +{ +#if defined(CONFIG_MEDIA_CONTROLLER) + struct media_entity *entity = &sd->entity; +#endif + 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); + 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, 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(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_device_release_subdev_node(struct video_device *vdev) +{ + struct v4l2_subdev *sd = video_get_drvdata(vdev); + sd->devnode = NULL; + kfree(vdev); +} + +int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev) +{ + 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); + strlcpy(vdev->name, sd->name, sizeof(vdev->name)); + vdev->v4l2_dev = v4l2_dev; + vdev->fops = &v4l2_subdev_fops; + vdev->release = v4l2_device_release_subdev_node; + vdev->ctrl_handler = sd->ctrl_handler; + 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 + video_unregister_device(sd->devnode); + if (!sd->owner_v4l2_dev) + module_put(sd->owner); +} +EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev); |