[funini.com] -> [kei@sodan] -> Kernel Reading

root/include/media/videobuf-core.h

/* [<][>][^][v][top][bottom][index][help] */

INCLUDED FROM


/*
 * 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>
#ifdef CONFIG_VIDEO_V4L1_COMPAT
#include <linux/videodev.h>
#endif
#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 contingous 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;
        unsigned long start;
        unsigned long end;
        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;
        unsigned int            input;
        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;

        void *(*alloc)          (size_t size);
        void *(*vmalloc)        (struct videobuf_buffer *buf);
        int (*iolock)           (struct videobuf_queue* q,
                                 struct videobuf_buffer *vb,
                                 struct v4l2_framebuffer *fbuf);
        int (*mmap)             (struct videobuf_queue *q,
                                 unsigned int *count,
                                 unsigned int *size,
                                 enum v4l2_memory memory);
        int (*sync)             (struct videobuf_queue* q,
                                 struct videobuf_buffer *buf);
        int (*video_copy_to_user)(struct videobuf_queue *q,
                                 char __user *data,
                                 size_t count,
                                 int nonblocking);
        int (*copy_stream)      (struct videobuf_queue *q,
                                 char __user *data,
                                 size_t count,
                                 size_t pos,
                                 int vbihack,
                                 int nonblocking);
        int (*mmap_free)        (struct videobuf_queue *q);
        int (*mmap_mapper)      (struct videobuf_queue *q,
                                struct vm_area_struct *vma);
};

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

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

        enum v4l2_buf_type         type;
        unsigned int               inputs; /* for V4L2_BUF_FLAG_INPUT */
        unsigned int               msize;
        enum v4l2_field            field;
        enum v4l2_field            last;   /* for field=V4L2_FIELD_ALTERNATE */
        struct videobuf_buffer     *bufs[VIDEO_MAX_FRAME];
        struct videobuf_queue_ops  *ops;
        struct videobuf_qtype_ops  *int_ops;

        unsigned int               streaming:1;
        unsigned int               reading:1;
        unsigned int               is_mmapped: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;
};

int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr);
int videobuf_iolock(struct videobuf_queue* q, struct videobuf_buffer *vb,
                struct v4l2_framebuffer *fbuf);

void *videobuf_alloc(struct videobuf_queue* q);

/* Used on videobuf-dvb */
void *videobuf_queue_to_vmalloc (struct videobuf_queue* q,
                                 struct videobuf_buffer *buf);

void videobuf_queue_core_init(struct videobuf_queue *q,
                         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);
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);
#ifdef CONFIG_VIDEO_V4L1_COMPAT
int videobuf_cgmbuf(struct videobuf_queue *q,
                    struct video_mbuf *mbuf, int count);
#endif
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);
unsigned int 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

/* [<][>][^][v][top][bottom][index][help] */

[funini.com] -> [kei@sodan] -> Kernel Reading