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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 *
4 * V 4 L 2 D R I V E R H E L P E R A P I
5 *
6 * Moved from videodev2.h
7 *
8 * Some commonly needed functions for drivers (v4l2-common.o module)
9 */
10#ifndef _V4L2_DEV_H
11#define _V4L2_DEV_H
12
13#include <linux/poll.h>
14#include <linux/fs.h>
15#include <linux/device.h>
16#include <linux/cdev.h>
17#include <linux/mutex.h>
18#include <linux/videodev2.h>
19
20#include <media/media-entity.h>
21
22#define VIDEO_MAJOR 81
23
24/**
25 * enum vfl_devnode_type - type of V4L2 device node
26 *
27 * @VFL_TYPE_VIDEO: for video input/output devices
28 * @VFL_TYPE_VBI: for vertical blank data (i.e. closed captions, teletext)
29 * @VFL_TYPE_RADIO: for radio tuners
30 * @VFL_TYPE_SUBDEV: for V4L2 subdevices
31 * @VFL_TYPE_SDR: for Software Defined Radio tuners
32 * @VFL_TYPE_TOUCH: for touch sensors
33 * @VFL_TYPE_MAX: number of VFL types, must always be last in the enum
34 */
35enum vfl_devnode_type {
36 VFL_TYPE_VIDEO,
37 VFL_TYPE_VBI,
38 VFL_TYPE_RADIO,
39 VFL_TYPE_SUBDEV,
40 VFL_TYPE_SDR,
41 VFL_TYPE_TOUCH,
42 VFL_TYPE_MAX /* Shall be the last one */
43};
44
45/**
46 * enum vfl_devnode_direction - Identifies if a &struct video_device
47 * corresponds to a receiver, a transmitter or a mem-to-mem device.
48 *
49 * @VFL_DIR_RX: device is a receiver.
50 * @VFL_DIR_TX: device is a transmitter.
51 * @VFL_DIR_M2M: device is a memory to memory device.
52 *
53 * Note: Ignored if &enum vfl_devnode_type is %VFL_TYPE_SUBDEV.
54 */
55enum vfl_devnode_direction {
56 VFL_DIR_RX,
57 VFL_DIR_TX,
58 VFL_DIR_M2M,
59};
60
61struct v4l2_ioctl_callbacks;
62struct video_device;
63struct v4l2_device;
64struct v4l2_ctrl_handler;
65struct dentry;
66
67/**
68 * enum v4l2_video_device_flags - Flags used by &struct video_device
69 *
70 * @V4L2_FL_REGISTERED:
71 * indicates that a &struct video_device is registered.
72 * Drivers can clear this flag if they want to block all future
73 * device access. It is cleared by video_unregister_device.
74 * @V4L2_FL_USES_V4L2_FH:
75 * indicates that file->private_data points to &struct v4l2_fh.
76 * This flag is set by the core when v4l2_fh_init() is called.
77 * All new drivers should use it.
78 * @V4L2_FL_QUIRK_INVERTED_CROP:
79 * some old M2M drivers use g/s_crop/cropcap incorrectly: crop and
80 * compose are swapped. If this flag is set, then the selection
81 * targets are swapped in the g/s_crop/cropcap functions in v4l2-ioctl.c.
82 * This allows those drivers to correctly implement the selection API,
83 * but the old crop API will still work as expected in order to preserve
84 * backwards compatibility.
85 * Never set this flag for new drivers.
86 * @V4L2_FL_SUBDEV_RO_DEVNODE:
87 * indicates that the video device node is registered in read-only mode.
88 * The flag only applies to device nodes registered for sub-devices, it is
89 * set by the core when the sub-devices device nodes are registered with
90 * v4l2_device_register_ro_subdev_nodes() and used by the sub-device ioctl
91 * handler to restrict access to some ioctl calls.
92 */
93enum v4l2_video_device_flags {
94 V4L2_FL_REGISTERED = 0,
95 V4L2_FL_USES_V4L2_FH = 1,
96 V4L2_FL_QUIRK_INVERTED_CROP = 2,
97 V4L2_FL_SUBDEV_RO_DEVNODE = 3,
98};
99
100/* Priority helper functions */
101
102/**
103 * struct v4l2_prio_state - stores the priority states
104 *
105 * @prios: array with elements to store the array priorities
106 *
107 *
108 * .. note::
109 * The size of @prios array matches the number of priority types defined
110 * by enum &v4l2_priority.
111 */
112struct v4l2_prio_state {
113 atomic_t prios[4];
114};
115
116/**
117 * v4l2_prio_init - initializes a struct v4l2_prio_state
118 *
119 * @global: pointer to &struct v4l2_prio_state
120 */
121void v4l2_prio_init(struct v4l2_prio_state *global);
122
123/**
124 * v4l2_prio_change - changes the v4l2 file handler priority
125 *
126 * @global: pointer to the &struct v4l2_prio_state of the device node.
127 * @local: pointer to the desired priority, as defined by enum &v4l2_priority
128 * @new: Priority type requested, as defined by enum &v4l2_priority.
129 *
130 * .. note::
131 * This function should be used only by the V4L2 core.
132 */
133int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
134 enum v4l2_priority new);
135
136/**
137 * v4l2_prio_open - Implements the priority logic for a file handler open
138 *
139 * @global: pointer to the &struct v4l2_prio_state of the device node.
140 * @local: pointer to the desired priority, as defined by enum &v4l2_priority
141 *
142 * .. note::
143 * This function should be used only by the V4L2 core.
144 */
145void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local);
146
147/**
148 * v4l2_prio_close - Implements the priority logic for a file handler close
149 *
150 * @global: pointer to the &struct v4l2_prio_state of the device node.
151 * @local: priority to be released, as defined by enum &v4l2_priority
152 *
153 * .. note::
154 * This function should be used only by the V4L2 core.
155 */
156void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local);
157
158/**
159 * v4l2_prio_max - Return the maximum priority, as stored at the @global array.
160 *
161 * @global: pointer to the &struct v4l2_prio_state of the device node.
162 *
163 * .. note::
164 * This function should be used only by the V4L2 core.
165 */
166enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global);
167
168/**
169 * v4l2_prio_check - Implements the priority logic for a file handler close
170 *
171 * @global: pointer to the &struct v4l2_prio_state of the device node.
172 * @local: desired priority, as defined by enum &v4l2_priority local
173 *
174 * .. note::
175 * This function should be used only by the V4L2 core.
176 */
177int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local);
178
179/**
180 * struct v4l2_file_operations - fs operations used by a V4L2 device
181 *
182 * @owner: pointer to struct module
183 * @read: operations needed to implement the read() syscall
184 * @write: operations needed to implement the write() syscall
185 * @poll: operations needed to implement the poll() syscall
186 * @unlocked_ioctl: operations needed to implement the ioctl() syscall
187 * @compat_ioctl32: operations needed to implement the ioctl() syscall for
188 * the special case where the Kernel uses 64 bits instructions, but
189 * the userspace uses 32 bits.
190 * @get_unmapped_area: called by the mmap() syscall, used when %!CONFIG_MMU
191 * @mmap: operations needed to implement the mmap() syscall
192 * @open: operations needed to implement the open() syscall
193 * @release: operations needed to implement the release() syscall
194 *
195 * .. note::
196 *
197 * Those operations are used to implemente the fs struct file_operations
198 * at the V4L2 drivers. The V4L2 core overrides the fs ops with some
199 * extra logic needed by the subsystem.
200 */
201struct v4l2_file_operations {
202 struct module *owner;
203 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
204 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
205 __poll_t (*poll) (struct file *, struct poll_table_struct *);
206 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
207#ifdef CONFIG_COMPAT
208 long (*compat_ioctl32) (struct file *, unsigned int, unsigned long);
209#endif
210 unsigned long (*get_unmapped_area) (struct file *, unsigned long,
211 unsigned long, unsigned long, unsigned long);
212 int (*mmap) (struct file *, struct vm_area_struct *);
213 int (*open) (struct file *);
214 int (*release) (struct file *);
215};
216
217/*
218 * Newer version of video_device, handled by videodev2.c
219 * This version moves redundant code from video device code to
220 * the common handler
221 */
222
223/**
224 * struct video_device - Structure used to create and manage the V4L2 device
225 * nodes.
226 *
227 * @entity: &struct media_entity
228 * @intf_devnode: pointer to &struct media_intf_devnode
229 * @pipe: &struct media_pipeline
230 * @fops: pointer to &struct v4l2_file_operations for the video device
231 * @device_caps: device capabilities as used in v4l2_capabilities
232 * @dev: &struct device for the video device
233 * @cdev: character device
234 * @v4l2_dev: pointer to &struct v4l2_device parent
235 * @dev_parent: pointer to &struct device parent
236 * @ctrl_handler: Control handler associated with this device node.
237 * May be NULL.
238 * @queue: &struct vb2_queue associated with this device node. May be NULL.
239 * @prio: pointer to &struct v4l2_prio_state with device's Priority state.
240 * If NULL, then v4l2_dev->prio will be used.
241 * @name: video device name
242 * @vfl_type: V4L device type, as defined by &enum vfl_devnode_type
243 * @vfl_dir: V4L receiver, transmitter or m2m
244 * @minor: device node 'minor'. It is set to -1 if the registration failed
245 * @num: number of the video device node
246 * @flags: video device flags. Use bitops to set/clear/test flags.
247 * Contains a set of &enum v4l2_video_device_flags.
248 * @index: attribute to differentiate multiple indices on one physical device
249 * @fh_lock: Lock for all v4l2_fhs
250 * @fh_list: List of &struct v4l2_fh
251 * @dev_debug: Internal device debug flags, not for use by drivers
252 * @tvnorms: Supported tv norms
253 *
254 * @release: video device release() callback
255 * @ioctl_ops: pointer to &struct v4l2_ioctl_ops with ioctl callbacks
256 *
257 * @valid_ioctls: bitmap with the valid ioctls for this device
258 * @lock: pointer to &struct mutex serialization lock
259 *
260 * .. note::
261 * Only set @dev_parent if that can't be deduced from @v4l2_dev.
262 */
263
264struct video_device {
265#if defined(CONFIG_MEDIA_CONTROLLER)
266 struct media_entity entity;
267 struct media_intf_devnode *intf_devnode;
268 struct media_pipeline pipe;
269#endif
270 const struct v4l2_file_operations *fops;
271
272 u32 device_caps;
273
274 /* sysfs */
275 struct device dev;
276 struct cdev *cdev;
277
278 struct v4l2_device *v4l2_dev;
279 struct device *dev_parent;
280
281 struct v4l2_ctrl_handler *ctrl_handler;
282
283 struct vb2_queue *queue;
284
285 struct v4l2_prio_state *prio;
286
287 /* device info */
288 char name[64];
289 enum vfl_devnode_type vfl_type;
290 enum vfl_devnode_direction vfl_dir;
291 int minor;
292 u16 num;
293 unsigned long flags;
294 int index;
295
296 /* V4L2 file handles */
297 spinlock_t fh_lock;
298 struct list_head fh_list;
299
300 int dev_debug;
301
302 v4l2_std_id tvnorms;
303
304 /* callbacks */
305 void (*release)(struct video_device *vdev);
306 const struct v4l2_ioctl_ops *ioctl_ops;
307 DECLARE_BITMAP(valid_ioctls, BASE_VIDIOC_PRIVATE);
308
309 struct mutex *lock;
310};
311
312/**
313 * media_entity_to_video_device - Returns a &struct video_device from
314 * the &struct media_entity embedded on it.
315 *
316 * @__entity: pointer to &struct media_entity
317 */
318#define media_entity_to_video_device(__entity) \
319 container_of(__entity, struct video_device, entity)
320
321/**
322 * to_video_device - Returns a &struct video_device from the
323 * &struct device embedded on it.
324 *
325 * @cd: pointer to &struct device
326 */
327#define to_video_device(cd) container_of(cd, struct video_device, dev)
328
329/**
330 * __video_register_device - register video4linux devices
331 *
332 * @vdev: struct video_device to register
333 * @type: type of device to register, as defined by &enum vfl_devnode_type
334 * @nr: which device node number is desired:
335 * (0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free)
336 * @warn_if_nr_in_use: warn if the desired device node number
337 * was already in use and another number was chosen instead.
338 * @owner: module that owns the video device node
339 *
340 * The registration code assigns minor numbers and device node numbers
341 * based on the requested type and registers the new device node with
342 * the kernel.
343 *
344 * This function assumes that struct video_device was zeroed when it
345 * was allocated and does not contain any stale date.
346 *
347 * An error is returned if no free minor or device node number could be
348 * found, or if the registration of the device node failed.
349 *
350 * Returns 0 on success.
351 *
352 * .. note::
353 *
354 * This function is meant to be used only inside the V4L2 core.
355 * Drivers should use video_register_device() or
356 * video_register_device_no_warn().
357 */
358int __must_check __video_register_device(struct video_device *vdev,
359 enum vfl_devnode_type type,
360 int nr, int warn_if_nr_in_use,
361 struct module *owner);
362
363/**
364 * video_register_device - register video4linux devices
365 *
366 * @vdev: struct video_device to register
367 * @type: type of device to register, as defined by &enum vfl_devnode_type
368 * @nr: which device node number is desired:
369 * (0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free)
370 *
371 * Internally, it calls __video_register_device(). Please see its
372 * documentation for more details.
373 *
374 * .. note::
375 * if video_register_device fails, the release() callback of
376 * &struct video_device structure is *not* called, so the caller
377 * is responsible for freeing any data. Usually that means that
378 * you video_device_release() should be called on failure.
379 */
380static inline int __must_check video_register_device(struct video_device *vdev,
381 enum vfl_devnode_type type,
382 int nr)
383{
384 return __video_register_device(vdev, type, nr, 1, vdev->fops->owner);
385}
386
387/**
388 * video_register_device_no_warn - register video4linux devices
389 *
390 * @vdev: struct video_device to register
391 * @type: type of device to register, as defined by &enum vfl_devnode_type
392 * @nr: which device node number is desired:
393 * (0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free)
394 *
395 * This function is identical to video_register_device() except that no
396 * warning is issued if the desired device node number was already in use.
397 *
398 * Internally, it calls __video_register_device(). Please see its
399 * documentation for more details.
400 *
401 * .. note::
402 * if video_register_device fails, the release() callback of
403 * &struct video_device structure is *not* called, so the caller
404 * is responsible for freeing any data. Usually that means that
405 * you video_device_release() should be called on failure.
406 */
407static inline int __must_check
408video_register_device_no_warn(struct video_device *vdev,
409 enum vfl_devnode_type type, int nr)
410{
411 return __video_register_device(vdev, type, nr, 0, vdev->fops->owner);
412}
413
414/**
415 * video_unregister_device - Unregister video devices.
416 *
417 * @vdev: &struct video_device to register
418 *
419 * Does nothing if vdev == NULL or if video_is_registered() returns false.
420 */
421void video_unregister_device(struct video_device *vdev);
422
423/**
424 * video_device_alloc - helper function to alloc &struct video_device
425 *
426 * Returns NULL if %-ENOMEM or a &struct video_device on success.
427 */
428struct video_device * __must_check video_device_alloc(void);
429
430/**
431 * video_device_release - helper function to release &struct video_device
432 *
433 * @vdev: pointer to &struct video_device
434 *
435 * Can also be used for video_device->release\(\).
436 */
437void video_device_release(struct video_device *vdev);
438
439/**
440 * video_device_release_empty - helper function to implement the
441 * video_device->release\(\) callback.
442 *
443 * @vdev: pointer to &struct video_device
444 *
445 * This release function does nothing.
446 *
447 * It should be used when the video_device is a static global struct.
448 *
449 * .. note::
450 * Having a static video_device is a dubious construction at best.
451 */
452void video_device_release_empty(struct video_device *vdev);
453
454/**
455 * v4l2_disable_ioctl- mark that a given command isn't implemented.
456 * shouldn't use core locking
457 *
458 * @vdev: pointer to &struct video_device
459 * @cmd: ioctl command
460 *
461 * This function allows drivers to provide just one v4l2_ioctl_ops struct, but
462 * disable ioctls based on the specific card that is actually found.
463 *
464 * .. note::
465 *
466 * This must be called before video_register_device.
467 * See also the comments for determine_valid_ioctls().
468 */
469static inline void v4l2_disable_ioctl(struct video_device *vdev,
470 unsigned int cmd)
471{
472 if (_IOC_NR(cmd) < BASE_VIDIOC_PRIVATE)
473 set_bit(_IOC_NR(cmd), vdev->valid_ioctls);
474}
475
476/**
477 * video_get_drvdata - gets private data from &struct video_device.
478 *
479 * @vdev: pointer to &struct video_device
480 *
481 * returns a pointer to the private data
482 */
483static inline void *video_get_drvdata(struct video_device *vdev)
484{
485 return dev_get_drvdata(&vdev->dev);
486}
487
488/**
489 * video_set_drvdata - sets private data from &struct video_device.
490 *
491 * @vdev: pointer to &struct video_device
492 * @data: private data pointer
493 */
494static inline void video_set_drvdata(struct video_device *vdev, void *data)
495{
496 dev_set_drvdata(&vdev->dev, data);
497}
498
499/**
500 * video_devdata - gets &struct video_device from struct file.
501 *
502 * @file: pointer to struct file
503 */
504struct video_device *video_devdata(struct file *file);
505
506/**
507 * video_drvdata - gets private data from &struct video_device using the
508 * struct file.
509 *
510 * @file: pointer to struct file
511 *
512 * This is function combines both video_get_drvdata() and video_devdata()
513 * as this is used very often.
514 */
515static inline void *video_drvdata(struct file *file)
516{
517 return video_get_drvdata(video_devdata(file));
518}
519
520/**
521 * video_device_node_name - returns the video device name
522 *
523 * @vdev: pointer to &struct video_device
524 *
525 * Returns the device name string
526 */
527static inline const char *video_device_node_name(struct video_device *vdev)
528{
529 return dev_name(&vdev->dev);
530}
531
532/**
533 * video_is_registered - returns true if the &struct video_device is registered.
534 *
535 *
536 * @vdev: pointer to &struct video_device
537 */
538static inline int video_is_registered(struct video_device *vdev)
539{
540 return test_bit(V4L2_FL_REGISTERED, &vdev->flags);
541}
542
543/**
544 * v4l2_debugfs_root - returns the dentry of the top-level "v4l2" debugfs dir
545 *
546 * If this directory does not yet exist, then it will be created.
547 */
548#ifdef CONFIG_DEBUG_FS
549struct dentry *v4l2_debugfs_root(void);
550#else
551static inline struct dentry *v4l2_debugfs_root(void)
552{
553 return NULL;
554}
555#endif
556
557#if defined(CONFIG_MEDIA_CONTROLLER)
558
559/**
560 * video_device_pipeline_start - Mark a pipeline as streaming
561 * @vdev: Starting video device
562 * @pipe: Media pipeline to be assigned to all entities in the pipeline.
563 *
564 * Mark all entities connected to a given video device through enabled links,
565 * either directly or indirectly, as streaming. The given pipeline object is
566 * assigned to every pad in the pipeline and stored in the media_pad pipe
567 * field.
568 *
569 * Calls to this function can be nested, in which case the same number of
570 * video_device_pipeline_stop() calls will be required to stop streaming. The
571 * pipeline pointer must be identical for all nested calls to
572 * video_device_pipeline_start().
573 *
574 * The video device must contain a single pad.
575 *
576 * This is a convenience wrapper around media_pipeline_start().
577 */
578__must_check int video_device_pipeline_start(struct video_device *vdev,
579 struct media_pipeline *pipe);
580
581/**
582 * __video_device_pipeline_start - Mark a pipeline as streaming
583 * @vdev: Starting video device
584 * @pipe: Media pipeline to be assigned to all entities in the pipeline.
585 *
586 * ..note:: This is the non-locking version of video_device_pipeline_start()
587 *
588 * The video device must contain a single pad.
589 *
590 * This is a convenience wrapper around __media_pipeline_start().
591 */
592__must_check int __video_device_pipeline_start(struct video_device *vdev,
593 struct media_pipeline *pipe);
594
595/**
596 * video_device_pipeline_stop - Mark a pipeline as not streaming
597 * @vdev: Starting video device
598 *
599 * Mark all entities connected to a given video device through enabled links,
600 * either directly or indirectly, as not streaming. The media_pad pipe field
601 * is reset to %NULL.
602 *
603 * If multiple calls to media_pipeline_start() have been made, the same
604 * number of calls to this function are required to mark the pipeline as not
605 * streaming.
606 *
607 * The video device must contain a single pad.
608 *
609 * This is a convenience wrapper around media_pipeline_stop().
610 */
611void video_device_pipeline_stop(struct video_device *vdev);
612
613/**
614 * __video_device_pipeline_stop - Mark a pipeline as not streaming
615 * @vdev: Starting video device
616 *
617 * .. note:: This is the non-locking version of media_pipeline_stop()
618 *
619 * The video device must contain a single pad.
620 *
621 * This is a convenience wrapper around __media_pipeline_stop().
622 */
623void __video_device_pipeline_stop(struct video_device *vdev);
624
625/**
626 * video_device_pipeline_alloc_start - Mark a pipeline as streaming
627 * @vdev: Starting video device
628 *
629 * video_device_pipeline_alloc_start() is similar to video_device_pipeline_start()
630 * but instead of working on a given pipeline the function will use an
631 * existing pipeline if the video device is already part of a pipeline, or
632 * allocate a new pipeline.
633 *
634 * Calls to video_device_pipeline_alloc_start() must be matched with
635 * video_device_pipeline_stop().
636 */
637__must_check int video_device_pipeline_alloc_start(struct video_device *vdev);
638
639/**
640 * video_device_pipeline - Get the media pipeline a video device is part of
641 * @vdev: The video device
642 *
643 * This function returns the media pipeline that a video device has been
644 * associated with when constructing the pipeline with
645 * video_device_pipeline_start(). The pointer remains valid until
646 * video_device_pipeline_stop() is called.
647 *
648 * Return: The media_pipeline the video device is part of, or NULL if the video
649 * device is not part of any pipeline.
650 *
651 * The video device must contain a single pad.
652 *
653 * This is a convenience wrapper around media_entity_pipeline().
654 */
655struct media_pipeline *video_device_pipeline(struct video_device *vdev);
656
657#endif /* CONFIG_MEDIA_CONTROLLER */
658
659#endif /* _V4L2_DEV_H */
1/*
2 *
3 * V 4 L 2 D R I V E R H E L P E R A P I
4 *
5 * Moved from videodev2.h
6 *
7 * Some commonly needed functions for drivers (v4l2-common.o module)
8 */
9#ifndef _V4L2_DEV_H
10#define _V4L2_DEV_H
11
12#include <linux/poll.h>
13#include <linux/fs.h>
14#include <linux/device.h>
15#include <linux/cdev.h>
16#include <linux/mutex.h>
17#include <linux/videodev2.h>
18
19#include <media/media-entity.h>
20
21#define VIDEO_MAJOR 81
22
23#define VFL_TYPE_GRABBER 0
24#define VFL_TYPE_VBI 1
25#define VFL_TYPE_RADIO 2
26#define VFL_TYPE_SUBDEV 3
27#define VFL_TYPE_SDR 4
28#define VFL_TYPE_TOUCH 5
29#define VFL_TYPE_MAX 6
30
31/* Is this a receiver, transmitter or mem-to-mem? */
32/* Ignored for VFL_TYPE_SUBDEV. */
33#define VFL_DIR_RX 0
34#define VFL_DIR_TX 1
35#define VFL_DIR_M2M 2
36
37struct v4l2_ioctl_callbacks;
38struct video_device;
39struct v4l2_device;
40struct v4l2_ctrl_handler;
41
42/* Flag to mark the video_device struct as registered.
43 Drivers can clear this flag if they want to block all future
44 device access. It is cleared by video_unregister_device. */
45#define V4L2_FL_REGISTERED (0)
46/* file->private_data points to struct v4l2_fh */
47#define V4L2_FL_USES_V4L2_FH (1)
48
49/* Priority helper functions */
50
51/**
52 * struct v4l2_prio_state - stores the priority states
53 *
54 * @prios: array with elements to store the array priorities
55 *
56 *
57 * .. note::
58 * The size of @prios array matches the number of priority types defined
59 * by enum &v4l2_priority.
60 */
61struct v4l2_prio_state {
62 atomic_t prios[4];
63};
64
65/**
66 * v4l2_prio_init - initializes a struct v4l2_prio_state
67 *
68 * @global: pointer to &struct v4l2_prio_state
69 */
70void v4l2_prio_init(struct v4l2_prio_state *global);
71
72/**
73 * v4l2_prio_change - changes the v4l2 file handler priority
74 *
75 * @global: pointer to the &struct v4l2_prio_state of the device node.
76 * @local: pointer to the desired priority, as defined by enum &v4l2_priority
77 * @new: Priority type requested, as defined by enum &v4l2_priority.
78 *
79 * .. note::
80 * This function should be used only by the V4L2 core.
81 */
82int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
83 enum v4l2_priority new);
84
85/**
86 * v4l2_prio_open - Implements the priority logic for a file handler open
87 *
88 * @global: pointer to the &struct v4l2_prio_state of the device node.
89 * @local: pointer to the desired priority, as defined by enum &v4l2_priority
90 *
91 * .. note::
92 * This function should be used only by the V4L2 core.
93 */
94void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local);
95
96/**
97 * v4l2_prio_close - Implements the priority logic for a file handler close
98 *
99 * @global: pointer to the &struct v4l2_prio_state of the device node.
100 * @local: priority to be released, as defined by enum &v4l2_priority
101 *
102 * .. note::
103 * This function should be used only by the V4L2 core.
104 */
105void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local);
106
107/**
108 * v4l2_prio_max - Return the maximum priority, as stored at the @global array.
109 *
110 * @global: pointer to the &struct v4l2_prio_state of the device node.
111 *
112 * .. note::
113 * This function should be used only by the V4L2 core.
114 */
115enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global);
116
117/**
118 * v4l2_prio_check - Implements the priority logic for a file handler close
119 *
120 * @global: pointer to the &struct v4l2_prio_state of the device node.
121 * @local: desired priority, as defined by enum &v4l2_priority local
122 *
123 * .. note::
124 * This function should be used only by the V4L2 core.
125 */
126int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local);
127
128/**
129 * struct v4l2_file_operations - fs operations used by a V4L2 device
130 *
131 * @owner: pointer to struct module
132 * @read: operations needed to implement the read() syscall
133 * @write: operations needed to implement the write() syscall
134 * @poll: operations needed to implement the poll() syscall
135 * @unlocked_ioctl: operations needed to implement the ioctl() syscall
136 * @compat_ioctl32: operations needed to implement the ioctl() syscall for
137 * the special case where the Kernel uses 64 bits instructions, but
138 * the userspace uses 32 bits.
139 * @get_unmapped_area: called by the mmap() syscall, used when %!CONFIG_MMU
140 * @mmap: operations needed to implement the mmap() syscall
141 * @open: operations needed to implement the open() syscall
142 * @release: operations needed to implement the release() syscall
143 *
144 * .. note::
145 *
146 * Those operations are used to implemente the fs struct file_operations
147 * at the V4L2 drivers. The V4L2 core overrides the fs ops with some
148 * extra logic needed by the subsystem.
149 */
150struct v4l2_file_operations {
151 struct module *owner;
152 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
153 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
154 unsigned int (*poll) (struct file *, struct poll_table_struct *);
155 long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
156#ifdef CONFIG_COMPAT
157 long (*compat_ioctl32) (struct file *, unsigned int, unsigned long);
158#endif
159 unsigned long (*get_unmapped_area) (struct file *, unsigned long,
160 unsigned long, unsigned long, unsigned long);
161 int (*mmap) (struct file *, struct vm_area_struct *);
162 int (*open) (struct file *);
163 int (*release) (struct file *);
164};
165
166/*
167 * Newer version of video_device, handled by videodev2.c
168 * This version moves redundant code from video device code to
169 * the common handler
170 */
171
172/**
173 * struct video_device - Structure used to create and manage the V4L2 device
174 * nodes.
175 *
176 * @entity: &struct media_entity
177 * @intf_devnode: pointer to &struct media_intf_devnode
178 * @pipe: &struct media_pipeline
179 * @fops: pointer to &struct v4l2_file_operations for the video device
180 * @device_caps: device capabilities as used in v4l2_capabilities
181 * @dev: &struct device for the video device
182 * @cdev: character device
183 * @v4l2_dev: pointer to &struct v4l2_device parent
184 * @dev_parent: pointer to &struct device parent
185 * @ctrl_handler: Control handler associated with this device node.
186 * May be NULL.
187 * @queue: &struct vb2_queue associated with this device node. May be NULL.
188 * @prio: pointer to &struct v4l2_prio_state with device's Priority state.
189 * If NULL, then v4l2_dev->prio will be used.
190 * @name: video device name
191 * @vfl_type: V4L device type
192 * @vfl_dir: V4L receiver, transmitter or m2m
193 * @minor: device node 'minor'. It is set to -1 if the registration failed
194 * @num: number of the video device node
195 * @flags: video device flags. Use bitops to set/clear/test flags
196 * @index: attribute to differentiate multiple indices on one physical device
197 * @fh_lock: Lock for all v4l2_fhs
198 * @fh_list: List of &struct v4l2_fh
199 * @dev_debug: Internal device debug flags, not for use by drivers
200 * @tvnorms: Supported tv norms
201 *
202 * @release: video device release() callback
203 * @ioctl_ops: pointer to &struct v4l2_ioctl_ops with ioctl callbacks
204 *
205 * @valid_ioctls: bitmap with the valid ioctls for this device
206 * @disable_locking: bitmap with the ioctls that don't require locking
207 * @lock: pointer to &struct mutex serialization lock
208 *
209 * .. note::
210 * Only set @dev_parent if that can't be deduced from @v4l2_dev.
211 */
212
213struct video_device
214{
215#if defined(CONFIG_MEDIA_CONTROLLER)
216 struct media_entity entity;
217 struct media_intf_devnode *intf_devnode;
218 struct media_pipeline pipe;
219#endif
220 const struct v4l2_file_operations *fops;
221
222 u32 device_caps;
223
224 /* sysfs */
225 struct device dev;
226 struct cdev *cdev;
227
228 struct v4l2_device *v4l2_dev;
229 struct device *dev_parent;
230
231 struct v4l2_ctrl_handler *ctrl_handler;
232
233 struct vb2_queue *queue;
234
235 struct v4l2_prio_state *prio;
236
237 /* device info */
238 char name[32];
239 int vfl_type;
240 int vfl_dir;
241 int minor;
242 u16 num;
243 unsigned long flags;
244 int index;
245
246 /* V4L2 file handles */
247 spinlock_t fh_lock;
248 struct list_head fh_list;
249
250 int dev_debug;
251
252 v4l2_std_id tvnorms;
253
254 /* callbacks */
255 void (*release)(struct video_device *vdev);
256 const struct v4l2_ioctl_ops *ioctl_ops;
257 DECLARE_BITMAP(valid_ioctls, BASE_VIDIOC_PRIVATE);
258
259 DECLARE_BITMAP(disable_locking, BASE_VIDIOC_PRIVATE);
260 struct mutex *lock;
261};
262
263#define media_entity_to_video_device(__e) \
264 container_of(__e, struct video_device, entity)
265/* dev to video-device */
266#define to_video_device(cd) container_of(cd, struct video_device, dev)
267
268/**
269 * __video_register_device - register video4linux devices
270 *
271 * @vdev: struct video_device to register
272 * @type: type of device to register
273 * @nr: which device node number is desired:
274 * (0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free)
275 * @warn_if_nr_in_use: warn if the desired device node number
276 * was already in use and another number was chosen instead.
277 * @owner: module that owns the video device node
278 *
279 * The registration code assigns minor numbers and device node numbers
280 * based on the requested type and registers the new device node with
281 * the kernel.
282 *
283 * This function assumes that struct video_device was zeroed when it
284 * was allocated and does not contain any stale date.
285 *
286 * An error is returned if no free minor or device node number could be
287 * found, or if the registration of the device node failed.
288 *
289 * Returns 0 on success.
290 *
291 * Valid values for @type are:
292 *
293 * - %VFL_TYPE_GRABBER - A frame grabber
294 * - %VFL_TYPE_VBI - Vertical blank data (undecoded)
295 * - %VFL_TYPE_RADIO - A radio card
296 * - %VFL_TYPE_SUBDEV - A subdevice
297 * - %VFL_TYPE_SDR - Software Defined Radio
298 * - %VFL_TYPE_TOUCH - A touch sensor
299 *
300 * .. note::
301 *
302 * This function is meant to be used only inside the V4L2 core.
303 * Drivers should use video_register_device() or
304 * video_register_device_no_warn().
305 */
306int __must_check __video_register_device(struct video_device *vdev, int type,
307 int nr, int warn_if_nr_in_use, struct module *owner);
308
309/**
310 * video_register_device - register video4linux devices
311 *
312 * @vdev: struct video_device to register
313 * @type: type of device to register
314 * @nr: which device node number is desired:
315 * (0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free)
316 *
317 * Internally, it calls __video_register_device(). Please see its
318 * documentation for more details.
319 *
320 * .. note::
321 * if video_register_device fails, the release() callback of
322 * &struct video_device structure is *not* called, so the caller
323 * is responsible for freeing any data. Usually that means that
324 * you video_device_release() should be called on failure.
325 */
326static inline int __must_check video_register_device(struct video_device *vdev,
327 int type, int nr)
328{
329 return __video_register_device(vdev, type, nr, 1, vdev->fops->owner);
330}
331
332/**
333 * video_register_device_no_warn - register video4linux devices
334 *
335 * @vdev: struct video_device to register
336 * @type: type of device to register
337 * @nr: which device node number is desired:
338 * (0 == /dev/video0, 1 == /dev/video1, ..., -1 == first free)
339 *
340 * This function is identical to video_register_device() except that no
341 * warning is issued if the desired device node number was already in use.
342 *
343 * Internally, it calls __video_register_device(). Please see its
344 * documentation for more details.
345 *
346 * .. note::
347 * if video_register_device fails, the release() callback of
348 * &struct video_device structure is *not* called, so the caller
349 * is responsible for freeing any data. Usually that means that
350 * you video_device_release() should be called on failure.
351 */
352static inline int __must_check video_register_device_no_warn(
353 struct video_device *vdev, int type, int nr)
354{
355 return __video_register_device(vdev, type, nr, 0, vdev->fops->owner);
356}
357
358/**
359 * video_unregister_device - Unregister video devices.
360 *
361 * @vdev: &struct video_device to register
362 *
363 * Does nothing if vdev == NULL or if video_is_registered() returns false.
364 */
365void video_unregister_device(struct video_device *vdev);
366
367/**
368 * video_device_alloc - helper function to alloc &struct video_device
369 *
370 * Returns NULL if %-ENOMEM or a &struct video_device on success.
371 */
372struct video_device * __must_check video_device_alloc(void);
373
374/**
375 * video_device_release - helper function to release &struct video_device
376 *
377 * @vdev: pointer to &struct video_device
378 *
379 * Can also be used for video_device->release\(\).
380 */
381void video_device_release(struct video_device *vdev);
382
383/**
384 * video_device_release_empty - helper function to implement the
385 * video_device->release\(\) callback.
386 *
387 * @vdev: pointer to &struct video_device
388 *
389 * This release function does nothing.
390 *
391 * It should be used when the video_device is a static global struct.
392 *
393 * .. note::
394 * Having a static video_device is a dubious construction at best.
395 */
396void video_device_release_empty(struct video_device *vdev);
397
398/**
399 * v4l2_is_known_ioctl - Checks if a given cmd is a known V4L ioctl
400 *
401 * @cmd: ioctl command
402 *
403 * returns true if cmd is a known V4L2 ioctl
404 */
405bool v4l2_is_known_ioctl(unsigned int cmd);
406
407/** v4l2_disable_ioctl_locking - mark that a given command
408 * shouldn't use core locking
409 *
410 * @vdev: pointer to &struct video_device
411 * @cmd: ioctl command
412 */
413static inline void v4l2_disable_ioctl_locking(struct video_device *vdev,
414 unsigned int cmd)
415{
416 if (_IOC_NR(cmd) < BASE_VIDIOC_PRIVATE)
417 set_bit(_IOC_NR(cmd), vdev->disable_locking);
418}
419
420/**
421 * v4l2_disable_ioctl- mark that a given command isn't implemented.
422 * shouldn't use core locking
423 *
424 * @vdev: pointer to &struct video_device
425 * @cmd: ioctl command
426 *
427 * This function allows drivers to provide just one v4l2_ioctl_ops struct, but
428 * disable ioctls based on the specific card that is actually found.
429 *
430 * .. note::
431 *
432 * This must be called before video_register_device.
433 * See also the comments for determine_valid_ioctls().
434 */
435static inline void v4l2_disable_ioctl(struct video_device *vdev,
436 unsigned int cmd)
437{
438 if (_IOC_NR(cmd) < BASE_VIDIOC_PRIVATE)
439 set_bit(_IOC_NR(cmd), vdev->valid_ioctls);
440}
441
442/**
443 * video_get_drvdata - gets private data from &struct video_device.
444 *
445 * @vdev: pointer to &struct video_device
446 *
447 * returns a pointer to the private data
448 */
449static inline void *video_get_drvdata(struct video_device *vdev)
450{
451 return dev_get_drvdata(&vdev->dev);
452}
453
454/**
455 * video_set_drvdata - sets private data from &struct video_device.
456 *
457 * @vdev: pointer to &struct video_device
458 * @data: private data pointer
459 */
460static inline void video_set_drvdata(struct video_device *vdev, void *data)
461{
462 dev_set_drvdata(&vdev->dev, data);
463}
464
465/**
466 * video_devdata - gets &struct video_device from struct file.
467 *
468 * @file: pointer to struct file
469 */
470struct video_device *video_devdata(struct file *file);
471
472/**
473 * video_drvdata - gets private data from &struct video_device using the
474 * struct file.
475 *
476 * @file: pointer to struct file
477 *
478 * This is function combines both video_get_drvdata() and video_devdata()
479 * as this is used very often.
480 */
481static inline void *video_drvdata(struct file *file)
482{
483 return video_get_drvdata(video_devdata(file));
484}
485
486/**
487 * video_device_node_name - returns the video device name
488 *
489 * @vdev: pointer to &struct video_device
490 *
491 * Returns the device name string
492 */
493static inline const char *video_device_node_name(struct video_device *vdev)
494{
495 return dev_name(&vdev->dev);
496}
497
498/**
499 * video_is_registered - returns true if the &struct video_device is registered.
500 *
501 *
502 * @vdev: pointer to &struct video_device
503 */
504static inline int video_is_registered(struct video_device *vdev)
505{
506 return test_bit(V4L2_FL_REGISTERED, &vdev->flags);
507}
508
509#endif /* _V4L2_DEV_H */