| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * |
| * V 4 L 2 D R I V E R H E L P E R A P I |
| * |
| * Moved from videodev2.h |
| * |
| * Some commonly needed functions for drivers (v4l2-common.o module) |
| */ |
| #ifndef _V4L2_DEV_H |
| #define _V4L2_DEV_H |
| |
| #include <linux/poll.h> |
| #include <linux/fs.h> |
| #include <linux/device.h> |
| #include <linux/cdev.h> |
| #include <linux/mutex.h> |
| #include <linux/videodev2.h> |
| |
| #include <media/media-entity.h> |
| |
| #define VIDEO_MAJOR 81 |
| |
| /** |
| * enum vfl_devnode_type - type of V4L2 device node |
| * |
| * @VFL_TYPE_VIDEO: for video input/output devices |
| * @VFL_TYPE_GRABBER: deprecated, same as VFL_TYPE_VIDEO |
| * @VFL_TYPE_VBI: for vertical blank data (i.e. closed captions, teletext) |
| * @VFL_TYPE_RADIO: for radio tuners |
| * @VFL_TYPE_SUBDEV: for V4L2 subdevices |
| * @VFL_TYPE_SDR: for Software Defined Radio tuners |
| * @VFL_TYPE_TOUCH: for touch sensors |
| * @VFL_TYPE_MAX: number of VFL types, must always be last in the enum |
| */ |
| enum vfl_devnode_type { |
| VFL_TYPE_VIDEO, |
| VFL_TYPE_GRABBER = VFL_TYPE_VIDEO, |
| VFL_TYPE_VBI, |
| VFL_TYPE_RADIO, |
| VFL_TYPE_SUBDEV, |
| VFL_TYPE_SDR, |
| VFL_TYPE_TOUCH, |
| VFL_TYPE_MAX /* Shall be the last one */ |
| }; |
| |
| /** |
| * enum vfl_direction - Identifies if a &struct video_device corresponds |
| * to a receiver, a transmitter or a mem-to-mem device. |
| * |
| * @VFL_DIR_RX: device is a receiver. |
| * @VFL_DIR_TX: device is a transmitter. |
| * @VFL_DIR_M2M: device is a memory to memory device. |
| * |
| * Note: Ignored if &enum vfl_devnode_type is %VFL_TYPE_SUBDEV. |
| */ |
| enum vfl_devnode_direction { |
| VFL_DIR_RX, |
| VFL_DIR_TX, |
| VFL_DIR_M2M, |
| }; |
| |
| struct v4l2_ioctl_callbacks; |
| struct video_device; |
| struct v4l2_device; |
| struct v4l2_ctrl_handler; |
| |
| /** |
| * enum v4l2_video_device_flags - Flags used by &struct video_device |
| * |
| * @V4L2_FL_REGISTERED: |
| * indicates that a &struct video_device is registered. |
| * Drivers can clear this flag if they want to block all future |
| * device access. It is cleared by video_unregister_device. |
| * @V4L2_FL_USES_V4L2_FH: |
| * indicates that file->private_data points to &struct v4l2_fh. |
| * This flag is set by the core when v4l2_fh_init() is called. |
| * All new drivers should use it. |
| * @V4L2_FL_QUIRK_INVERTED_CROP: |
| * some old M2M drivers use g/s_crop/cropcap incorrectly: crop and |
| * compose are swapped. If this flag is set, then the selection |
| * targets are swapped in the g/s_crop/cropcap functions in v4l2-ioctl.c. |
| * This allows those drivers to correctly implement the selection API, |
| * but the old crop API will still work as expected in order to preserve |
| * backwards compatibility. |
| * Never set this flag for new drivers. |
| */ |
| enum v4l2_video_device_flags { |
| V4L2_FL_REGISTERED = 0, |
| V4L2_FL_USES_V4L2_FH = 1, |
| V4L2_FL_QUIRK_INVERTED_CROP = 2, |
| }; |
| |
| /* Priority helper functions */ |
| |
| /** |
| * struct v4l2_prio_state - stores the priority states |
| * |
| * @prios: array with elements to store the array priorities |
| * |
| * |
| * .. note:: |
| * The size of @prios array matches the number of priority types defined |
| * by enum &v4l2_priority. |
| */ |
| struct v4l2_prio_state { |
| atomic_t prios[4]; |
| }; |
| |
| /** |
| * v4l2_prio_init - initializes a struct v4l2_prio_state |
| * |
| * @global: pointer to &struct v4l2_prio_state |
| */ |
| void v4l2_prio_init(struct v4l2_prio_state *global); |
| |
| /** |
| * v4l2_prio_change - changes the v4l2 file handler priority |
| * |
| * @global: pointer to the &struct v4l2_prio_state of the device node. |
| * @local: pointer to the desired priority, as defined by enum &v4l2_priority |
| * @new: Priority type requested, as defined by enum &v4l2_priority. |
| * |
| * .. note:: |
| * This function should be used only by the V4L2 core. |
| */ |
| int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local, |
| enum v4l2_priority new); |
| |
| /** |
| * v4l2_prio_open - Implements the priority logic for a file handler open |
| * |
| * @global: pointer to the &struct v4l2_prio_state of the device node. |
| * @local: pointer to the desired priority, as defined by enum &v4l2_priority |
| * |
| * .. note:: |
| * This function should be used only by the V4L2 core. |
| */ |
| void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local); |
| |
| /** |
| * v4l2_prio_close - Implements the priority logic for a file handler close |
| * |
| * @global: pointer to the &struct v4l2_prio_state of the device node. |
| * @local: priority to be released, as defined by enum &v4l2_priority |
| * |
| * .. note:: |
| * This function should be used only by the V4L2 core. |
| */ |
| void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local); |
| |
| /** |
| * v4l2_prio_max - Return the maximum priority, as stored at the @global array. |
| * |
| * @global: pointer to the &struct v4l2_prio_state of the device node. |
| * |
| * .. note:: |
| * This function should be used only by the V4L2 core. |
| */ |
| enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global); |
| |
| /** |
| * v4l2_prio_check - Implements the priority logic for a file handler close |
| * |
| * @global: pointer to the &struct v4l2_prio_state of the device node. |
| * @local: desired priority, as defined by enum &v4l2_priority local |
| * |
| * .. note:: |
| * This function should be used only by the V4L2 core. |
| */ |
| int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local); |
| |
| /** |
| * struct v4l2_file_operations - fs operations used by a V4L2 device |
| * |
| * @owner: pointer to struct module |
| * @read: operations needed to implement the read() syscall |
| * @write: operations needed to implement the write() syscall |
| * @poll: operations needed to implement the poll() syscall |
| * @unlocked_ioctl: operations needed to implement the ioctl() syscall |
| * @compat_ioctl32: operations needed to implement the ioctl() syscall for |
| * the special case where the Kernel uses 64 bits instructions, but |
| * the userspace uses 32 bits. |
| * @get_unmapped_area: called by the mmap() syscall, used when %!CONFIG_MMU |
| * @mmap: operations needed to implement the mmap() syscall |
| * @open: operations needed to implement the open() syscall |
| * @release: operations needed to implement the release() syscall |
| * |
| * .. note:: |
| * |
| * Those operations are used to implemente the fs struct file_operations |
| * at the V4L2 drivers. The V4L2 core overrides the fs ops with some |
| * extra logic needed by the subsystem. |
| */ |
| struct v4l2_file_operations { |
| struct module *owner; |
| ssize_t (*read) (struct file *, char __user *, size_t, loff_t *); |
| ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *); |
| __poll_t (*poll) (struct file *, struct poll_table_struct *); |
| long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long); |
| #ifdef CONFIG_COMPAT |
| long (*compat_ioctl32) (struct file *, unsigned int, unsigned long); |
| #endif |
| unsigned long (*get_unmapped_area) (struct file *, unsigned long, |
| unsigned long, unsigned long, unsigned long); |
| int (*mmap) (struct file *, struct vm_area_struct *); |
| int (*open) (struct file *); |
| int (*release) (struct file *); |
| }; |
| |
| /* |
| * Newer version of video_device, handled by videodev2.c |
| * This version moves redundant code from video device code to |
| * the common handler |
| */ |
| |
| /** |
| * struct video_device - Structure used to create and manage the V4L2 device |
| * nodes. |
| * |
| * @entity: &struct media_entity |
| * @intf_devnode: pointer to &struct media_intf_devnode |
| * @pipe: &struct media_pipeline |
| * @fops: pointer to &struct v4l2_file_operations for the video device |
| * @device_caps: device capabilities as used in v4l2_capabilities |
| * @dev: &struct device for the video device |
| * @cdev: character device |
| * @v4l2_dev: pointer to &struct v4l2_device parent |
| * @dev_parent: pointer to &struct device parent |
| * @ctrl_handler: Control handler associated with this device node. |
| * May be NULL. |
| * @queue: &struct vb2_queue associated with this device node. May be NULL. |
| * @prio: pointer to &struct v4l2_prio_state with device's Priority state. |
| * If NULL, then v4l2_dev->prio will be used. |
| * @name: video device name |
| * @vfl_type: V4L device type, as defined by &enum vfl_devnode_type |
| * @vfl_dir: V4L receiver, transmitter or m2m |
| * @minor: device node 'minor'. It is set to -1 if the registration failed |
| * @num: number of the video device node |
| * @flags: video device flags. Use bitops to set/clear/test flags. |
| * Contains a set of &enum v4l2_video_device_flags. |
| * @index: attribute to differentiate multiple indices on one physical device |
| * @fh_lock: Lock for all v4l2_fhs |
| * @fh_list: List of &struct v4l2_fh |
| * @dev_debug: Internal device debug flags, not for use by drivers |
| * @tvnorms: Supported tv norms |
| * |
| * @release: video device release() callback |
| * @ioctl_ops: pointer to &struct v4l2_ioctl_ops with ioctl callbacks |
| * |
| * @valid_ioctls: bitmap with the valid ioctls for this device |
| * @lock: pointer to &struct mutex serialization lock |
| * |
| * .. note:: |
| * Only set @dev_parent if that can't be deduced from @v4l2_dev. |
| */ |
| |
| struct video_device |
| { |
| #if defined(CONFIG_MEDIA_CONTROLLER) |
| struct media_entity entity; |
| struct media_intf_devnode *intf_devnode; |
| struct media_pipeline pipe; |
| #endif |
| const struct v4l2_file_operations *fops; |
| |
| u32 device_caps; |
| |
| /* sysfs */ |
| struct device dev; |
| struct cdev *cdev; |
| |
| struct v4l2_device *v4l2_dev; |
| struct device *dev_parent; |
| |
| struct v4l2_ctrl_handler *ctrl_handler; |
| |
| struct vb2_queue *queue; |
| |
| struct v4l2_prio_state *prio; |
| |
| /* device info */ |
| char name[32]; |
| enum vfl_devnode_type vfl_type; |
| enum vfl_devnode_direction vfl_dir; |
| int minor; |
| u16 num; |
| unsigned long flags; |
| int index; |
| |
| /* V4L2 file handles */ |
| spinlock_t fh_lock; |
| struct list_head fh_list; |
| |
| int dev_debug; |
| |
| v4l2_std_id tvnorms; |
| |
| /* callbacks */ |
| void (*release)(struct video_device *vdev); |
| const struct v4l2_ioctl_ops *ioctl_ops; |
| DECLARE_BITMAP(valid_ioctls, BASE_VIDIOC_PRIVATE); |
| |
| struct mutex *lock; |
| }; |
| |
| /** |
| * media_entity_to_video_device - Returns a &struct video_device from |
| * the &struct media_entity embedded on it. |
| * |
| * @__entity: pointer to &struct media_entity |
| */ |
| #define media_entity_to_video_device(__entity) \ |
| container_of(__entity, struct video_device, entity) |
| |
| /** |
| * to_video_device - Returns a &struct video_device from the |
| * &struct device embedded on it. |
| * |
| * @cd: pointer to &struct device |
| */ |
| #define to_video_device(cd) container_of(cd, struct video_device, dev) |
| |
| /** |
| * __video_register_device - register video4linux devices |
| * |
| * @vdev: struct video_device to register |
| * @type: type of device to register, as defined by &enum vfl_devnode_type |
| * @nr: which device node number is desired: |
| * (0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free) |
| * @warn_if_nr_in_use: warn if the desired device node number |
| * was already in use and another number was chosen instead. |
| * @owner: module that owns the video device node |
| * |
| * The registration code assigns minor numbers and device node numbers |
| * based on the requested type and registers the new device node with |
| * the kernel. |
| * |
| * This function assumes that struct video_device was zeroed when it |
| * was allocated and does not contain any stale date. |
| * |
| * An error is returned if no free minor or device node number could be |
| * found, or if the registration of the device node failed. |
| * |
| * Returns 0 on success. |
| * |
| * .. note:: |
| * |
| * This function is meant to be used only inside the V4L2 core. |
| * Drivers should use video_register_device() or |
| * video_register_device_no_warn(). |
| */ |
| int __must_check __video_register_device(struct video_device *vdev, |
| enum vfl_devnode_type type, |
| int nr, int warn_if_nr_in_use, |
| struct module *owner); |
| |
| /** |
| * video_register_device - register video4linux devices |
| * |
| * @vdev: struct video_device to register |
| * @type: type of device to register, as defined by &enum vfl_devnode_type |
| * @nr: which device node number is desired: |
| * (0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free) |
| * |
| * Internally, it calls __video_register_device(). Please see its |
| * documentation for more details. |
| * |
| * .. note:: |
| * if video_register_device fails, the release() callback of |
| * &struct video_device structure is *not* called, so the caller |
| * is responsible for freeing any data. Usually that means that |
| * you video_device_release() should be called on failure. |
| */ |
| static inline int __must_check video_register_device(struct video_device *vdev, |
| enum vfl_devnode_type type, |
| int nr) |
| { |
| return __video_register_device(vdev, type, nr, 1, vdev->fops->owner); |
| } |
| |
| /** |
| * video_register_device_no_warn - register video4linux devices |
| * |
| * @vdev: struct video_device to register |
| * @type: type of device to register, as defined by &enum vfl_devnode_type |
| * @nr: which device node number is desired: |
| * (0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free) |
| * |
| * This function is identical to video_register_device() except that no |
| * warning is issued if the desired device node number was already in use. |
| * |
| * Internally, it calls __video_register_device(). Please see its |
| * documentation for more details. |
| * |
| * .. note:: |
| * if video_register_device fails, the release() callback of |
| * &struct video_device structure is *not* called, so the caller |
| * is responsible for freeing any data. Usually that means that |
| * you video_device_release() should be called on failure. |
| */ |
| static inline int __must_check |
| video_register_device_no_warn(struct video_device *vdev, |
| enum vfl_devnode_type type, int nr) |
| { |
| return __video_register_device(vdev, type, nr, 0, vdev->fops->owner); |
| } |
| |
| /** |
| * video_unregister_device - Unregister video devices. |
| * |
| * @vdev: &struct video_device to register |
| * |
| * Does nothing if vdev == NULL or if video_is_registered() returns false. |
| */ |
| void video_unregister_device(struct video_device *vdev); |
| |
| /** |
| * video_device_alloc - helper function to alloc &struct video_device |
| * |
| * Returns NULL if %-ENOMEM or a &struct video_device on success. |
| */ |
| struct video_device * __must_check video_device_alloc(void); |
| |
| /** |
| * video_device_release - helper function to release &struct video_device |
| * |
| * @vdev: pointer to &struct video_device |
| * |
| * Can also be used for video_device->release\(\). |
| */ |
| void video_device_release(struct video_device *vdev); |
| |
| /** |
| * video_device_release_empty - helper function to implement the |
| * video_device->release\(\) callback. |
| * |
| * @vdev: pointer to &struct video_device |
| * |
| * This release function does nothing. |
| * |
| * It should be used when the video_device is a static global struct. |
| * |
| * .. note:: |
| * Having a static video_device is a dubious construction at best. |
| */ |
| void video_device_release_empty(struct video_device *vdev); |
| |
| /** |
| * v4l2_disable_ioctl- mark that a given command isn't implemented. |
| * shouldn't use core locking |
| * |
| * @vdev: pointer to &struct video_device |
| * @cmd: ioctl command |
| * |
| * This function allows drivers to provide just one v4l2_ioctl_ops struct, but |
| * disable ioctls based on the specific card that is actually found. |
| * |
| * .. note:: |
| * |
| * This must be called before video_register_device. |
| * See also the comments for determine_valid_ioctls(). |
| */ |
| static inline void v4l2_disable_ioctl(struct video_device *vdev, |
| unsigned int cmd) |
| { |
| if (_IOC_NR(cmd) < BASE_VIDIOC_PRIVATE) |
| set_bit(_IOC_NR(cmd), vdev->valid_ioctls); |
| } |
| |
| /** |
| * video_get_drvdata - gets private data from &struct video_device. |
| * |
| * @vdev: pointer to &struct video_device |
| * |
| * returns a pointer to the private data |
| */ |
| static inline void *video_get_drvdata(struct video_device *vdev) |
| { |
| return dev_get_drvdata(&vdev->dev); |
| } |
| |
| /** |
| * video_set_drvdata - sets private data from &struct video_device. |
| * |
| * @vdev: pointer to &struct video_device |
| * @data: private data pointer |
| */ |
| static inline void video_set_drvdata(struct video_device *vdev, void *data) |
| { |
| dev_set_drvdata(&vdev->dev, data); |
| } |
| |
| /** |
| * video_devdata - gets &struct video_device from struct file. |
| * |
| * @file: pointer to struct file |
| */ |
| struct video_device *video_devdata(struct file *file); |
| |
| /** |
| * video_drvdata - gets private data from &struct video_device using the |
| * struct file. |
| * |
| * @file: pointer to struct file |
| * |
| * This is function combines both video_get_drvdata() and video_devdata() |
| * as this is used very often. |
| */ |
| static inline void *video_drvdata(struct file *file) |
| { |
| return video_get_drvdata(video_devdata(file)); |
| } |
| |
| /** |
| * video_device_node_name - returns the video device name |
| * |
| * @vdev: pointer to &struct video_device |
| * |
| * Returns the device name string |
| */ |
| static inline const char *video_device_node_name(struct video_device *vdev) |
| { |
| return dev_name(&vdev->dev); |
| } |
| |
| /** |
| * video_is_registered - returns true if the &struct video_device is registered. |
| * |
| * |
| * @vdev: pointer to &struct video_device |
| */ |
| static inline int video_is_registered(struct video_device *vdev) |
| { |
| return test_bit(V4L2_FL_REGISTERED, &vdev->flags); |
| } |
| |
| #endif /* _V4L2_DEV_H */ |