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v6.13.7
  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 */
v3.1
 
  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_MAX		4
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 28
 29struct v4l2_ioctl_callbacks;
 30struct video_device;
 31struct v4l2_device;
 32struct v4l2_ctrl_handler;
 
 33
 34/* Flag to mark the video_device struct as registered.
 35   Drivers can clear this flag if they want to block all future
 36   device access. It is cleared by video_unregister_device. */
 37#define V4L2_FL_REGISTERED	(0)
 38/* file->private_data points to struct v4l2_fh */
 39#define V4L2_FL_USES_V4L2_FH	(1)
 40/* Use the prio field of v4l2_fh for core priority checking */
 41#define V4L2_FL_USE_FH_PRIO	(2)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 42
 43/* Priority helper functions */
 44
 
 
 
 
 
 
 
 
 
 
 45struct v4l2_prio_state {
 46	atomic_t prios[4];
 47};
 48
 
 
 
 
 
 49void v4l2_prio_init(struct v4l2_prio_state *global);
 
 
 
 
 
 
 
 
 
 
 
 50int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
 51		     enum v4l2_priority new);
 
 
 
 
 
 
 
 
 
 
 52void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local);
 
 
 
 
 
 
 
 
 
 
 53void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local);
 
 
 
 
 
 
 
 
 
 54enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global);
 
 
 
 
 
 
 
 
 
 
 55int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local);
 56
 57
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 58struct v4l2_file_operations {
 59	struct module *owner;
 60	ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
 61	ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
 62	unsigned int (*poll) (struct file *, struct poll_table_struct *);
 63	long (*ioctl) (struct file *, unsigned int, unsigned long);
 64	long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
 
 
 
 65	unsigned long (*get_unmapped_area) (struct file *, unsigned long,
 66				unsigned long, unsigned long, unsigned long);
 67	int (*mmap) (struct file *, struct vm_area_struct *);
 68	int (*open) (struct file *);
 69	int (*release) (struct file *);
 70};
 71
 72/*
 73 * Newer version of video_device, handled by videodev2.c
 74 * 	This version moves redundant code from video device code to
 75 *	the common handler
 76 */
 77
 78struct video_device
 79{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 80#if defined(CONFIG_MEDIA_CONTROLLER)
 81	struct media_entity entity;
 
 
 82#endif
 83	/* device ops */
 84	const struct v4l2_file_operations *fops;
 85
 
 
 86	/* sysfs */
 87	struct device dev;		/* v4l device */
 88	struct cdev *cdev;		/* character device */
 89
 90	/* Set either parent or v4l2_dev if your driver uses v4l2_device */
 91	struct device *parent;		/* device parent */
 92	struct v4l2_device *v4l2_dev;	/* v4l2_device parent */
 93
 94	/* Control handler associated with this device node. May be NULL. */
 95	struct v4l2_ctrl_handler *ctrl_handler;
 96
 97	/* Priority state. If NULL, then v4l2_dev->prio will be used. */
 
 98	struct v4l2_prio_state *prio;
 99
100	/* device info */
101	char name[32];
102	int vfl_type;
103	/* 'minor' is set to -1 if the registration failed */
104	int minor;
105	u16 num;
106	/* use bitops to set/clear/test flags */
107	unsigned long flags;
108	/* attribute to differentiate multiple indices on one physical device */
109	int index;
110
111	/* V4L2 file handles */
112	spinlock_t		fh_lock; /* Lock for all v4l2_fhs */
113	struct list_head	fh_list; /* List of struct v4l2_fh */
114
115	int debug;			/* Activates debug level*/
116
117	/* Video standard vars */
118	v4l2_std_id tvnorms;		/* Supported tv norms */
119	v4l2_std_id current_norm;	/* Current tvnorm */
120
121	/* callbacks */
122	void (*release)(struct video_device *vdev);
123
124	/* ioctl callbacks */
125	const struct v4l2_ioctl_ops *ioctl_ops;
 
126
127	/* serialization lock */
128	struct mutex *lock;
129};
130
131#define media_entity_to_video_device(__e) \
132	container_of(__e, struct video_device, entity)
133/* dev to video-device */
 
 
 
 
 
 
 
 
 
 
 
 
134#define to_video_device(cd) container_of(cd, struct video_device, dev)
135
136int __must_check __video_register_device(struct video_device *vdev, int type,
137		int nr, int warn_if_nr_in_use, struct module *owner);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
138
139/* Register video devices. Note that if video_register_device fails,
140   the release() callback of the video_device structure is *not* called, so
141   the caller is responsible for freeing any data. Usually that means that
142   you call video_device_release() on failure. */
 
 
 
 
 
 
 
 
 
 
 
 
 
143static inline int __must_check video_register_device(struct video_device *vdev,
144		int type, int nr)
 
145{
146	return __video_register_device(vdev, type, nr, 1, vdev->fops->owner);
147}
148
149/* Same as video_register_device, but no warning is issued if the desired
150   device node number was already in use. */
151static inline int __must_check video_register_device_no_warn(
152		struct video_device *vdev, int type, int nr)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
153{
154	return __video_register_device(vdev, type, nr, 0, vdev->fops->owner);
155}
156
157/* Unregister video devices. Will do nothing if vdev == NULL or
158   video_is_registered() returns false. */
 
 
 
 
 
159void video_unregister_device(struct video_device *vdev);
160
161/* helper functions to alloc/release struct video_device, the
162   latter can also be used for video_device->release(). */
 
 
 
163struct video_device * __must_check video_device_alloc(void);
164
165/* this release function frees the vdev pointer */
 
 
 
 
 
 
166void video_device_release(struct video_device *vdev);
167
168/* this release function does nothing, use when the video_device is a
169   static global struct. Note that having a static video_device is
170   a dubious construction at best. */
 
 
 
 
 
 
 
 
 
 
171void video_device_release_empty(struct video_device *vdev);
172
173/* helper functions to access driver private data. */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
174static inline void *video_get_drvdata(struct video_device *vdev)
175{
176	return dev_get_drvdata(&vdev->dev);
177}
178
 
 
 
 
 
 
179static inline void video_set_drvdata(struct video_device *vdev, void *data)
180{
181	dev_set_drvdata(&vdev->dev, data);
182}
183
 
 
 
 
 
184struct video_device *video_devdata(struct file *file);
185
186/* Combine video_get_drvdata and video_devdata as this is
187   used very often. */
 
 
 
 
 
 
 
188static inline void *video_drvdata(struct file *file)
189{
190	return video_get_drvdata(video_devdata(file));
191}
192
 
 
 
 
 
 
 
193static inline const char *video_device_node_name(struct video_device *vdev)
194{
195	return dev_name(&vdev->dev);
196}
197
 
 
 
 
 
 
198static inline int video_is_registered(struct video_device *vdev)
199{
200	return test_bit(V4L2_FL_REGISTERED, &vdev->flags);
201}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
202
203#endif /* _V4L2_DEV_H */