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Release 4.16 include/media/videobuf-core.h

Directory: include/media
/*
 * generic helper functions for handling video4linux capture buffers
 *
 * (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org>
 *
 * Highly based on video-buf written originally by:
 * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org>
 * (c) 2006 Mauro Carvalho Chehab, <mchehab@infradead.org>
 * (c) 2006 Ted Walther and John Sokol
 *
 * 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
 */

#ifndef _VIDEOBUF_CORE_H

#define _VIDEOBUF_CORE_H

#include <linux/poll.h>
#include <linux/videodev2.h>


#define UNSET (-1U)


struct videobuf_buffer;
struct videobuf_queue;

/* --------------------------------------------------------------------- */

/*
 * A small set of helper functions to manage video4linux buffers.
 *
 * struct videobuf_buffer holds the data structures used by the helper
 * functions, additionally some commonly used fields for v4l buffers
 * (width, height, lists, waitqueue) are in there.  That struct should
 * be used as first element in the drivers buffer struct.
 *
 * about the mmap helpers (videobuf_mmap_*):
 *
 * The mmaper function allows to map any subset of contiguous buffers.
 * This includes one mmap() call for all buffers (which the original
 * video4linux API uses) as well as one mmap() for every single buffer
 * (which v4l2 uses).
 *
 * If there is a valid mapping for a buffer, buffer->baddr/bsize holds
 * userspace address + size which can be feeded into the
 * videobuf_dma_init_user function listed above.
 *
 */


struct videobuf_mapping {
	
unsigned int count;
	
struct videobuf_queue *q;
};


enum videobuf_state {
	
VIDEOBUF_NEEDS_INIT = 0,
	
VIDEOBUF_PREPARED   = 1,
	
VIDEOBUF_QUEUED     = 2,
	
VIDEOBUF_ACTIVE     = 3,
	
VIDEOBUF_DONE       = 4,
	
VIDEOBUF_ERROR      = 5,
	
VIDEOBUF_IDLE       = 6,
};


struct videobuf_buffer {
	
unsigned int            i;
	
u32                     magic;

	/* info about the buffer */
	
unsigned int            width;
	
unsigned int            height;
	
unsigned int            bytesperline; /* use only if != 0 */
	
unsigned long           size;
	
enum v4l2_field         field;
	
enum videobuf_state     state;
	
struct list_head        stream;  /* QBUF/DQBUF list */

	/* touched by irq handler */
	
struct list_head        queue;
	
wait_queue_head_t       done;
	
unsigned int            field_count;
	
struct timeval          ts;

	/* Memory type */
	
enum v4l2_memory        memory;

	/* buffer size */
	
size_t                  bsize;

	/* buffer offset (mmap + overlay) */
	
size_t                  boff;

	/* buffer addr (userland ptr!) */
	
unsigned long           baddr;

	/* for mmap'ed buffers */
	
struct videobuf_mapping *map;

	/* Private pointer to allow specific methods to store their data */
	
int			privsize;
	
void                    *priv;
};


struct videobuf_queue_ops {
	
int (*buf_setup)(struct videobuf_queue *q,
			 unsigned int *count, unsigned int *size);
	
int (*buf_prepare)(struct videobuf_queue *q,
			   struct videobuf_buffer *vb,
			   enum v4l2_field field);
	
void (*buf_queue)(struct videobuf_queue *q,
			  struct videobuf_buffer *vb);
	
void (*buf_release)(struct videobuf_queue *q,
			    struct videobuf_buffer *vb);
};


#define MAGIC_QTYPE_OPS	0x12261003

/* Helper operations - device type dependent */

struct videobuf_qtype_ops {
	
u32                     magic;

	
struct videobuf_buffer *(*alloc_vb)(size_t size);
	
void *(*vaddr)		(struct videobuf_buffer *buf);
	
int (*iolock)		(struct videobuf_queue *q,
				 struct videobuf_buffer *vb,
				 struct v4l2_framebuffer *fbuf);
	
int (*sync)		(struct videobuf_queue *q,
				 struct videobuf_buffer *buf);
	
int (*mmap_mapper)	(struct videobuf_queue *q,
				 struct videobuf_buffer *buf,
				 struct vm_area_struct *vma);
};


struct videobuf_queue {
	
struct mutex               vb_lock;
	
struct mutex               *ext_lock;
	
spinlock_t                 *irqlock;
	
struct device		   *dev;

	
wait_queue_head_t	   wait; /* wait if queue is empty */

	
enum v4l2_buf_type         type;
	
unsigned int               msize;
	
enum v4l2_field            field;
	
enum v4l2_field            last;   /* for field=V4L2_FIELD_ALTERNATE */
	
struct videobuf_buffer     *bufs[VIDEO_MAX_FRAME];
	
const struct videobuf_queue_ops  *ops;
	
struct videobuf_qtype_ops  *int_ops;

	
unsigned int               streaming:1;
	
unsigned int               reading:1;

	/* capture via mmap() + ioctl(QBUF/DQBUF) */
	
struct list_head           stream;

	/* capture via read() */
	
unsigned int               read_off;
	
struct videobuf_buffer     *read_buf;

	/* driver private data */
	
void                       *priv_data;
};


static inline void videobuf_queue_lock(struct videobuf_queue *q) { if (!q->ext_lock) mutex_lock(&q->vb_lock); }

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Total27100.00%1100.00%


static inline void videobuf_queue_unlock(struct videobuf_queue *q) { if (!q->ext_lock) mutex_unlock(&q->vb_lock); }

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int videobuf_waiton(struct videobuf_queue *q, struct videobuf_buffer *vb, int non_blocking, int intr); int videobuf_iolock(struct videobuf_queue *q, struct videobuf_buffer *vb, struct v4l2_framebuffer *fbuf); struct videobuf_buffer *videobuf_alloc_vb(struct videobuf_queue *q); /* Used on videobuf-dvb */ void *videobuf_queue_to_vaddr(struct videobuf_queue *q, struct videobuf_buffer *buf); void videobuf_queue_core_init(struct videobuf_queue *q, const struct videobuf_queue_ops *ops, struct device *dev, spinlock_t *irqlock, enum v4l2_buf_type type, enum v4l2_field field, unsigned int msize, void *priv, struct videobuf_qtype_ops *int_ops, struct mutex *ext_lock); int videobuf_queue_is_busy(struct videobuf_queue *q); void videobuf_queue_cancel(struct videobuf_queue *q); enum v4l2_field videobuf_next_field(struct videobuf_queue *q); int videobuf_reqbufs(struct videobuf_queue *q, struct v4l2_requestbuffers *req); int videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b); int videobuf_qbuf(struct videobuf_queue *q, struct v4l2_buffer *b); int videobuf_dqbuf(struct videobuf_queue *q, struct v4l2_buffer *b, int nonblocking); int videobuf_streamon(struct videobuf_queue *q); int videobuf_streamoff(struct videobuf_queue *q); void videobuf_stop(struct videobuf_queue *q); int videobuf_read_start(struct videobuf_queue *q); void videobuf_read_stop(struct videobuf_queue *q); ssize_t videobuf_read_stream(struct videobuf_queue *q, char __user *data, size_t count, loff_t *ppos, int vbihack, int nonblocking); ssize_t videobuf_read_one(struct videobuf_queue *q, char __user *data, size_t count, loff_t *ppos, int nonblocking); __poll_t videobuf_poll_stream(struct file *file, struct videobuf_queue *q, poll_table *wait); int videobuf_mmap_setup(struct videobuf_queue *q, unsigned int bcount, unsigned int bsize, enum v4l2_memory memory); int __videobuf_mmap_setup(struct videobuf_queue *q, unsigned int bcount, unsigned int bsize, enum v4l2_memory memory); int videobuf_mmap_free(struct videobuf_queue *q); int videobuf_mmap_mapper(struct videobuf_queue *q, struct vm_area_struct *vma); #endif

Overall Contributors

PersonTokensPropCommitsCommitProp
Mauro Carvalho Chehab73684.02%522.73%
Hans Verkuil809.13%731.82%
Brandon Philips293.31%418.18%
Arjan van de Ven212.40%14.55%
Guennadi Liakhovetski40.46%14.55%
Jonathan Corbet20.23%14.55%
Pawel Osciak20.23%14.55%
Al Viro10.11%14.55%
Masahiro Yamada10.11%14.55%
Total876100.00%22100.00%
Directory: include/media
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