Edit File: videobuf-core.h
/* * 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 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; 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); } static inline void videobuf_queue_unlock(struct videobuf_queue *q) { if (!q->ext_lock) mutex_unlock(&q->vb_lock); } 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); 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