cregit-Linux how code gets into the kernel

Release 4.7 include/media/videobuf2-core.h

Directory: include/media
/*
 * videobuf2-core.h - Video Buffer 2 Core Framework
 *
 * Copyright (C) 2010 Samsung Electronics
 *
 * Author: Pawel Osciak <pawel@osciak.com>
 *
 * 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.
 */
#ifndef _MEDIA_VIDEOBUF2_CORE_H

#define _MEDIA_VIDEOBUF2_CORE_H

#include <linux/mm_types.h>
#include <linux/mutex.h>
#include <linux/poll.h>
#include <linux/dma-buf.h>


#define VB2_MAX_FRAME	(32)

#define VB2_MAX_PLANES	(8)


enum vb2_memory {
	
VB2_MEMORY_UNKNOWN	= 0,
	
VB2_MEMORY_MMAP		= 1,
	
VB2_MEMORY_USERPTR	= 2,
	
VB2_MEMORY_DMABUF	= 4,
};

struct vb2_alloc_ctx;
struct vb2_fileio_data;
struct vb2_threadio_data;

/**
 * struct vb2_mem_ops - memory handling/memory allocator operations
 * @alloc:      allocate video memory and, optionally, allocator private data,
 *              return NULL on failure or a pointer to allocator private,
 *              per-buffer data on success; the returned private structure
 *              will then be passed as buf_priv argument to other ops in this
 *              structure. Additional gfp_flags to use when allocating the
 *              are also passed to this operation. These flags are from the
 *              gfp_flags field of vb2_queue.
 * @put:        inform the allocator that the buffer will no longer be used;
 *              usually will result in the allocator freeing the buffer (if
 *              no other users of this buffer are present); the buf_priv
 *              argument is the allocator private per-buffer structure
 *              previously returned from the alloc callback.
 * @get_dmabuf: acquire userspace memory for a hardware operation; used for
 *               DMABUF memory types.
 * @get_userptr: acquire userspace memory for a hardware operation; used for
 *               USERPTR memory types; vaddr is the address passed to the
 *               videobuf layer when queuing a video buffer of USERPTR type;
 *               should return an allocator private per-buffer structure
 *               associated with the buffer on success, NULL on failure;
 *               the returned private structure will then be passed as buf_priv
 *               argument to other ops in this structure.
 * @put_userptr: inform the allocator that a USERPTR buffer will no longer
 *               be used.
 * @attach_dmabuf: attach a shared struct dma_buf for a hardware operation;
 *                 used for DMABUF memory types; alloc_ctx is the alloc context
 *                 dbuf is the shared dma_buf; returns NULL on failure;
 *                 allocator private per-buffer structure on success;
 *                 this needs to be used for further accesses to the buffer.
 * @detach_dmabuf: inform the exporter of the buffer that the current DMABUF
 *                 buffer is no longer used; the buf_priv argument is the
 *                 allocator private per-buffer structure previously returned
 *                 from the attach_dmabuf callback.
 * @map_dmabuf: request for access to the dmabuf from allocator; the allocator
 *              of dmabuf is informed that this driver is going to use the
 *              dmabuf.
 * @unmap_dmabuf: releases access control to the dmabuf - allocator is notified
 *                that this driver is done using the dmabuf for now.
 * @prepare:    called every time the buffer is passed from userspace to the
 *              driver, useful for cache synchronisation, optional.
 * @finish:     called every time the buffer is passed back from the driver
 *              to the userspace, also optional.
 * @vaddr:      return a kernel virtual address to a given memory buffer
 *              associated with the passed private structure or NULL if no
 *              such mapping exists.
 * @cookie:     return allocator specific cookie for a given memory buffer
 *              associated with the passed private structure or NULL if not
 *              available.
 * @num_users:  return the current number of users of a memory buffer;
 *              return 1 if the videobuf layer (or actually the driver using
 *              it) is the only user.
 * @mmap:       setup a userspace mapping for a given memory buffer under
 *              the provided virtual memory region.
 *
 * Required ops for USERPTR types: get_userptr, put_userptr.
 * Required ops for MMAP types: alloc, put, num_users, mmap.
 * Required ops for read/write access types: alloc, put, num_users, vaddr.
 * Required ops for DMABUF types: attach_dmabuf, detach_dmabuf, map_dmabuf,
 *                                unmap_dmabuf.
 */

struct vb2_mem_ops {
	
void		*(*alloc)(void *alloc_ctx, unsigned long size,
				  enum dma_data_direction dma_dir,
				  gfp_t gfp_flags);
	
void		(*put)(void *buf_priv);
	
struct dma_buf *(*get_dmabuf)(void *buf_priv, unsigned long flags);

	
void		*(*get_userptr)(void *alloc_ctx, unsigned long vaddr,
					unsigned long size,
					enum dma_data_direction dma_dir);
	
void		(*put_userptr)(void *buf_priv);

	
void		(*prepare)(void *buf_priv);
	
void		(*finish)(void *buf_priv);

	
void		*(*attach_dmabuf)(void *alloc_ctx, struct dma_buf *dbuf,
					  unsigned long size,
					  enum dma_data_direction dma_dir);
	
void		(*detach_dmabuf)(void *buf_priv);
	
int		(*map_dmabuf)(void *buf_priv);
	
void		(*unmap_dmabuf)(void *buf_priv);

	
void		*(*vaddr)(void *buf_priv);
	
void		*(*cookie)(void *buf_priv);

	
unsigned int	(*num_users)(void *buf_priv);

	
int		(*mmap)(void *buf_priv, struct vm_area_struct *vma);
};

/**
 * struct vb2_plane - plane information
 * @mem_priv:   private data with this plane
 * @dbuf:       dma_buf - shared buffer object
 * @dbuf_mapped:        flag to show whether dbuf is mapped or not
 * @bytesused:  number of bytes occupied by data in the plane (payload)
 * @length:     size of this plane (NOT the payload) in bytes
 * @min_length: minimum required size of this plane (NOT the payload) in bytes.
 *              @length is always greater or equal to @min_length.
 * @offset:     when memory in the associated struct vb2_buffer is
 *              VB2_MEMORY_MMAP, equals the offset from the start of
 *              the device memory for this plane (or is a "cookie" that
 *              should be passed to mmap() called on the video node)
 * @userptr:    when memory is VB2_MEMORY_USERPTR, a userspace pointer
 *              pointing to this plane
 * @fd:         when memory is VB2_MEMORY_DMABUF, a userspace file
 *              descriptor associated with this plane
 * @m:          Union with memtype-specific data (@offset, @userptr or
 *              @fd).
 * @data_offset:        offset in the plane to the start of data; usually 0,
 *              unless there is a header in front of the data
 * Should contain enough information to be able to cover all the fields
 * of struct v4l2_plane at videodev2.h
 */

struct vb2_plane {
	
void			*mem_priv;
	
struct dma_buf		*dbuf;
	
unsigned int		dbuf_mapped;
	
unsigned int		bytesused;
	
unsigned int		length;
	
unsigned int		min_length;
	union {
		
unsigned int	offset;
		
unsigned long	userptr;
		
int		fd;
	} 
m;
	
unsigned int		data_offset;
};

/**
 * enum vb2_io_modes - queue access methods
 * @VB2_MMAP:           driver supports MMAP with streaming API
 * @VB2_USERPTR:        driver supports USERPTR with streaming API
 * @VB2_READ:           driver supports read() style access
 * @VB2_WRITE:          driver supports write() style access
 * @VB2_DMABUF:         driver supports DMABUF with streaming API
 */

enum vb2_io_modes {
	
VB2_MMAP	= (1 << 0),
	
VB2_USERPTR	= (1 << 1),
	
VB2_READ	= (1 << 2),
	
VB2_WRITE	= (1 << 3),
	
VB2_DMABUF	= (1 << 4),
};

/**
 * enum vb2_buffer_state - current video buffer state
 * @VB2_BUF_STATE_DEQUEUED:     buffer under userspace control
 * @VB2_BUF_STATE_PREPARING:    buffer is being prepared in videobuf
 * @VB2_BUF_STATE_PREPARED:     buffer prepared in videobuf and by the driver
 * @VB2_BUF_STATE_QUEUED:       buffer queued in videobuf, but not in driver
 * @VB2_BUF_STATE_REQUEUEING:   re-queue a buffer to the driver
 * @VB2_BUF_STATE_ACTIVE:       buffer queued in driver and possibly used
 *                              in a hardware operation
 * @VB2_BUF_STATE_DONE:         buffer returned from driver to videobuf, but
 *                              not yet dequeued to userspace
 * @VB2_BUF_STATE_ERROR:        same as above, but the operation on the buffer
 *                              has ended with an error, which will be reported
 *                              to the userspace when it is dequeued
 */

enum vb2_buffer_state {
	
VB2_BUF_STATE_DEQUEUED,
	
VB2_BUF_STATE_PREPARING,
	
VB2_BUF_STATE_PREPARED,
	
VB2_BUF_STATE_QUEUED,
	
VB2_BUF_STATE_REQUEUEING,
	
VB2_BUF_STATE_ACTIVE,
	
VB2_BUF_STATE_DONE,
	
VB2_BUF_STATE_ERROR,
};

struct vb2_queue;

/**
 * struct vb2_buffer - represents a video buffer
 * @vb2_queue:          the queue to which this driver belongs
 * @index:              id number of the buffer
 * @type:               buffer type
 * @memory:             the method, in which the actual data is passed
 * @num_planes:         number of planes in the buffer
 *                      on an internal driver queue
 * @planes:             private per-plane information; do not change
 * @timestamp:          frame timestamp in ns
 */

struct vb2_buffer {
	
struct vb2_queue	*vb2_queue;
	
unsigned int		index;
	
unsigned int		type;
	
unsigned int		memory;
	
unsigned int		num_planes;
	
struct vb2_plane	planes[VB2_MAX_PLANES];
	
u64			timestamp;

	/* private: internal use only
         *
         * state:               current buffer state; do not change
         * queued_entry:        entry on the queued buffers list, which holds
         *                      all buffers queued from userspace
         * done_entry:          entry on the list that stores all buffers ready
         *                      to be dequeued to userspace
         */
	
enum vb2_buffer_state	state;

	
struct list_head	queued_entry;
	
struct list_head	done_entry;
#ifdef CONFIG_VIDEO_ADV_DEBUG
	/*
         * Counters for how often these buffer-related ops are
         * called. Used to check for unbalanced ops.
         */
	
u32		cnt_mem_alloc;
	
u32		cnt_mem_put;
	
u32		cnt_mem_get_dmabuf;
	
u32		cnt_mem_get_userptr;
	
u32		cnt_mem_put_userptr;
	
u32		cnt_mem_prepare;
	
u32		cnt_mem_finish;
	
u32		cnt_mem_attach_dmabuf;
	
u32		cnt_mem_detach_dmabuf;
	
u32		cnt_mem_map_dmabuf;
	
u32		cnt_mem_unmap_dmabuf;
	
u32		cnt_mem_vaddr;
	
u32		cnt_mem_cookie;
	
u32		cnt_mem_num_users;
	
u32		cnt_mem_mmap;

	
u32		cnt_buf_init;
	
u32		cnt_buf_prepare;
	
u32		cnt_buf_finish;
	
u32		cnt_buf_cleanup;
	
u32		cnt_buf_queue;

	/* This counts the number of calls to vb2_buffer_done() */
	
u32		cnt_buf_done;
#endif
};

/**
 * struct vb2_ops - driver-specific callbacks
 *
 * @queue_setup:        called from VIDIOC_REQBUFS and VIDIOC_CREATE_BUFS
 *                      handlers before memory allocation. It can be called
 *                      twice: if the original number of requested buffers
 *                      could not be allocated, then it will be called a
 *                      second time with the actually allocated number of
 *                      buffers to verify if that is OK.
 *                      The driver should return the required number of buffers
 *                      in *num_buffers, the required number of planes per
 *                      buffer in *num_planes, the size of each plane should be
 *                      set in the sizes[] array and optional per-plane
 *                      allocator specific context in the alloc_ctxs[] array.
 *                      When called from VIDIOC_REQBUFS, *num_planes == 0, the
 *                      driver has to use the currently configured format to
 *                      determine the plane sizes and *num_buffers is the total
 *                      number of buffers that are being allocated. When called
 *                      from VIDIOC_CREATE_BUFS, *num_planes != 0 and it
 *                      describes the requested number of planes and sizes[]
 *                      contains the requested plane sizes. If either
 *                      *num_planes or the requested sizes are invalid callback
 *                      must return -EINVAL. In this case *num_buffers are
 *                      being allocated additionally to q->num_buffers.
 * @wait_prepare:       release any locks taken while calling vb2 functions;
 *                      it is called before an ioctl needs to wait for a new
 *                      buffer to arrive; required to avoid a deadlock in
 *                      blocking access type.
 * @wait_finish:        reacquire all locks released in the previous callback;
 *                      required to continue operation after sleeping while
 *                      waiting for a new buffer to arrive.
 * @buf_init:           called once after allocating a buffer (in MMAP case)
 *                      or after acquiring a new USERPTR buffer; drivers may
 *                      perform additional buffer-related initialization;
 *                      initialization failure (return != 0) will prevent
 *                      queue setup from completing successfully; optional.
 * @buf_prepare:        called every time the buffer is queued from userspace
 *                      and from the VIDIOC_PREPARE_BUF ioctl; drivers may
 *                      perform any initialization required before each
 *                      hardware operation in this callback; drivers can
 *                      access/modify the buffer here as it is still synced for
 *                      the CPU; drivers that support VIDIOC_CREATE_BUFS must
 *                      also validate the buffer size; if an error is returned,
 *                      the buffer will not be queued in driver; optional.
 * @buf_finish:         called before every dequeue of the buffer back to
 *                      userspace; the buffer is synced for the CPU, so drivers
 *                      can access/modify the buffer contents; drivers may
 *                      perform any operations required before userspace
 *                      accesses the buffer; optional. The buffer state can be
 *                      one of the following: DONE and ERROR occur while
 *                      streaming is in progress, and the PREPARED state occurs
 *                      when the queue has been canceled and all pending
 *                      buffers are being returned to their default DEQUEUED
 *                      state. Typically you only have to do something if the
 *                      state is VB2_BUF_STATE_DONE, since in all other cases
 *                      the buffer contents will be ignored anyway.
 * @buf_cleanup:        called once before the buffer is freed; drivers may
 *                      perform any additional cleanup; optional.
 * @start_streaming:    called once to enter 'streaming' state; the driver may
 *                      receive buffers with @buf_queue callback before
 *                      @start_streaming is called; the driver gets the number
 *                      of already queued buffers in count parameter; driver
 *                      can return an error if hardware fails, in that case all
 *                      buffers that have been already given by the @buf_queue
 *                      callback are to be returned by the driver by calling
 *                      @vb2_buffer_done(VB2_BUF_STATE_QUEUED).
 *                      If you need a minimum number of buffers before you can
 *                      start streaming, then set @min_buffers_needed in the
 *                      vb2_queue structure. If that is non-zero then
 *                      start_streaming won't be called until at least that
 *                      many buffers have been queued up by userspace.
 * @stop_streaming:     called when 'streaming' state must be disabled; driver
 *                      should stop any DMA transactions or wait until they
 *                      finish and give back all buffers it got from buf_queue()
 *                      callback by calling @vb2_buffer_done() with either
 *                      VB2_BUF_STATE_DONE or VB2_BUF_STATE_ERROR; may use
 *                      vb2_wait_for_all_buffers() function
 * @buf_queue:          passes buffer vb to the driver; driver may start
 *                      hardware operation on this buffer; driver should give
 *                      the buffer back by calling vb2_buffer_done() function;
 *                      it is allways called after calling STREAMON ioctl;
 *                      might be called before start_streaming callback if user
 *                      pre-queued buffers before calling STREAMON.
 */

struct vb2_ops {
	
int (*queue_setup)(struct vb2_queue *q,
			   unsigned int *num_buffers, unsigned int *num_planes,
			   unsigned int sizes[], void *alloc_ctxs[]);

	
void (*wait_prepare)(struct vb2_queue *q);
	
void (*wait_finish)(struct vb2_queue *q);

	
int (*buf_init)(struct vb2_buffer *vb);
	
int (*buf_prepare)(struct vb2_buffer *vb);
	
void (*buf_finish)(struct vb2_buffer *vb);
	
void (*buf_cleanup)(struct vb2_buffer *vb);

	
int (*start_streaming)(struct vb2_queue *q, unsigned int count);
	
void (*stop_streaming)(struct vb2_queue *q);

	
void (*buf_queue)(struct vb2_buffer *vb);
};

/**
 * struct vb2_ops - driver-specific callbacks
 *
 * @verify_planes_array: Verify that a given user space structure contains
 *                      enough planes for the buffer. This is called
 *                      for each dequeued buffer.
 * @fill_user_buffer:   given a vb2_buffer fill in the userspace structure.
 *                      For V4L2 this is a struct v4l2_buffer.
 * @fill_vb2_buffer:    given a userspace structure, fill in the vb2_buffer.
 *                      If the userspace structure is invalid, then this op
 *                      will return an error.
 * @copy_timestamp:     copy the timestamp from a userspace structure to
 *                      the vb2_buffer struct.
 */

struct vb2_buf_ops {
	
int (*verify_planes_array)(struct vb2_buffer *vb, const void *pb);
	
void (*fill_user_buffer)(struct vb2_buffer *vb, void *pb);
	
int (*fill_vb2_buffer)(struct vb2_buffer *vb, const void *pb,
				struct vb2_plane *planes);
	
void (*copy_timestamp)(struct vb2_buffer *vb, const void *pb);
};

/**
 * struct vb2_queue - a videobuf queue
 *
 * @type:       private buffer type whose content is defined by the vb2-core
 *              caller. For example, for V4L2, it should match
 *              the V4L2_BUF_TYPE_* in include/uapi/linux/videodev2.h
 * @io_modes:   supported io methods (see vb2_io_modes enum)
 * @fileio_read_once:           report EOF after reading the first buffer
 * @fileio_write_immediately:   queue buffer after each write() call
 * @allow_zero_bytesused:       allow bytesused == 0 to be passed to the driver
 * @quirk_poll_must_check_waiting_for_buffers: Return POLLERR at poll when QBUF
 *              has not been called. This is a vb1 idiom that has been adopted
 *              also by vb2.
 * @lock:       pointer to a mutex that protects the vb2_queue struct. The
 *              driver can set this to a mutex to let the v4l2 core serialize
 *              the queuing ioctls. If the driver wants to handle locking
 *              itself, then this should be set to NULL. This lock is not used
 *              by the videobuf2 core API.
 * @owner:      The filehandle that 'owns' the buffers, i.e. the filehandle
 *              that called reqbufs, create_buffers or started fileio.
 *              This field is not used by the videobuf2 core API, but it allows
 *              drivers to easily associate an owner filehandle with the queue.
 * @ops:        driver-specific callbacks
 * @mem_ops:    memory allocator specific callbacks
 * @buf_ops:    callbacks to deliver buffer information
 *              between user-space and kernel-space
 * @drv_priv:   driver private data
 * @buf_struct_size: size of the driver-specific buffer structure;
 *              "0" indicates the driver doesn't want to use a custom buffer
 *              structure type. for example, sizeof(struct vb2_v4l2_buffer)
 *              will be used for v4l2.
 * @timestamp_flags: Timestamp flags; V4L2_BUF_FLAG_TIMESTAMP_* and
 *              V4L2_BUF_FLAG_TSTAMP_SRC_*
 * @gfp_flags:  additional gfp flags used when allocating the buffers.
 *              Typically this is 0, but it may be e.g. GFP_DMA or __GFP_DMA32
 *              to force the buffer allocation to a specific memory zone.
 * @min_buffers_needed: the minimum number of buffers needed before
 *              start_streaming() can be called. Used when a DMA engine
 *              cannot be started unless at least this number of buffers
 *              have been queued into the driver.
 */
/*
 * Private elements (won't appear at the DocBook):
 * @mmap_lock:  private mutex used when buffers are allocated/freed/mmapped
 * @memory:     current memory type used
 * @bufs:       videobuf buffer structures
 * @num_buffers: number of allocated/used buffers
 * @queued_list: list of buffers currently queued from userspace
 * @queued_count: number of buffers queued and ready for streaming.
 * @owned_by_drv_count: number of buffers owned by the driver
 * @done_list:  list of buffers ready to be dequeued to userspace
 * @done_lock:  lock to protect done_list list
 * @done_wq:    waitqueue for processes waiting for buffers ready to be dequeued
 * @alloc_ctx:  memory type/allocator-specific contexts for each plane
 * @streaming:  current streaming state
 * @start_streaming_called: start_streaming() was called successfully and we
 *              started streaming.
 * @error:      a fatal error occurred on the queue
 * @waiting_for_buffers: used in poll() to check if vb2 is still waiting for
 *              buffers. Only set for capture queues if qbuf has not yet been
 *              called since poll() needs to return POLLERR in that situation.
 * @is_multiplanar: set if buffer type is multiplanar
 * @is_output:  set if buffer type is output
 * @copy_timestamp: set if vb2-core should set timestamps
 * @last_buffer_dequeued: used in poll() and DQBUF to immediately return if the
 *              last decoded buffer was already dequeued. Set for capture queues
 *              when a buffer with the V4L2_BUF_FLAG_LAST is dequeued.
 * @fileio:     file io emulator internal data, used only if emulator is active
 * @threadio:   thread io internal data, used only if thread is active
 */

struct vb2_queue {
	
unsigned int			type;
	
unsigned int			io_modes;
	
unsigned			fileio_read_once:1;
	
unsigned			fileio_write_immediately:1;
	
unsigned			allow_zero_bytesused:1;
	
unsigned		   quirk_poll_must_check_waiting_for_buffers:1;

	
struct mutex			*lock;
	
void				*owner;

	
const struct vb2_ops		*ops;
	
const struct vb2_mem_ops	*mem_ops;
	
const struct vb2_buf_ops	*buf_ops;

	
void				*drv_priv;
	
unsigned int			buf_struct_size;
	
u32				timestamp_flags;
	
gfp_t				gfp_flags;
	
u32				min_buffers_needed;

	/* private: internal use only */
	
struct mutex			mmap_lock;
	
unsigned int			memory;
	
struct vb2_buffer		*bufs[VB2_MAX_FRAME];
	
unsigned int			num_buffers;

	
struct list_head		queued_list;
	
unsigned int			queued_count;

	
atomic_t			owned_by_drv_count;
	
struct list_head		done_list;
	
spinlock_t			done_lock;
	
wait_queue_head_t		done_wq;

	
void				*alloc_ctx[VB2_MAX_PLANES];

	
unsigned int			streaming:1;
	
unsigned int			start_streaming_called:1;
	
unsigned int			error:1;
	
unsigned int			waiting_for_buffers:1;
	
unsigned int			is_multiplanar:1;
	
unsigned int			is_output:1;
	
unsigned int			copy_timestamp:1;
	
unsigned int			last_buffer_dequeued:1;

	
struct vb2_fileio_data		*fileio;
	
struct vb2_threadio_data	*threadio;

#ifdef CONFIG_VIDEO_ADV_DEBUG
	/*
         * Counters for how often these queue-related ops are
         * called. Used to check for unbalanced ops.
         */
	
u32				cnt_queue_setup;
	
u32				cnt_wait_prepare;
	
u32				cnt_wait_finish;
	
u32				cnt_start_streaming;
	
u32				cnt_stop_streaming;
#endif
};

void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no);
void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no);

void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state);
void vb2_discard_done(struct vb2_queue *q);
int vb2_wait_for_all_buffers(struct vb2_queue *q);

void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb);
int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
		unsigned int *count);
int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
		unsigned int *count, unsigned requested_planes,
		const unsigned int requested_sizes[]);
int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb);
int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb);
int vb2_core_dqbuf(struct vb2_queue *q, unsigned int *pindex, void *pb,
		   bool nonblocking);

int vb2_core_streamon(struct vb2_queue *q, unsigned int type);
int vb2_core_streamoff(struct vb2_queue *q, unsigned int type);

int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type,
		unsigned int index, unsigned int plane, unsigned int flags);

int vb2_core_queue_init(struct vb2_queue *q);
void vb2_core_queue_release(struct vb2_queue *q);

void vb2_queue_error(struct vb2_queue *q);

int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma);
#ifndef CONFIG_MMU
unsigned long vb2_get_unmapped_area(struct vb2_queue *q,
				    unsigned long addr,
				    unsigned long len,
				    unsigned long pgoff,
				    unsigned long flags);
#endif
unsigned int vb2_core_poll(struct vb2_queue *q, struct file *file,
		poll_table *wait);
size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count,
		loff_t *ppos, int nonblock);
size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count,
		loff_t *ppos, int nonblock);

/*
 * vb2_thread_fnc - callback function for use with vb2_thread
 *
 * This is called whenever a buffer is dequeued in the thread.
 */

typedef int (*vb2_thread_fnc)(struct vb2_buffer *vb, void *priv);

/**
 * vb2_thread_start() - start a thread for the given queue.
 * @q:          videobuf queue
 * @fnc:        callback function
 * @priv:       priv pointer passed to the callback function
 * @thread_name:the name of the thread. This will be prefixed with "vb2-".
 *
 * This starts a thread that will queue and dequeue until an error occurs
 * or @vb2_thread_stop is called.
 *
 * This function should not be used for anything else but the videobuf2-dvb
 * support. If you think you have another good use-case for this, then please
 * contact the linux-media mailinglist first.
 */
int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv,
		     const char *thread_name);

/**
 * vb2_thread_stop() - stop the thread for the given queue.
 * @q:          videobuf queue
 */
int vb2_thread_stop(struct vb2_queue *q);

/**
 * vb2_is_streaming() - return streaming status of the queue
 * @q:          videobuf queue
 */

static inline bool vb2_is_streaming(struct vb2_queue *q) { return q->streaming; }

Contributors

PersonTokensPropCommitsCommitProp
pawel osciakpawel osciak17100.00%1100.00%
Total17100.00%1100.00%

/** * vb2_fileio_is_active() - return true if fileio is active. * @q: videobuf queue * * This returns true if read() or write() is used to stream the data * as opposed to stream I/O. This is almost never an important distinction, * except in rare cases. One such case is that using read() or write() to * stream a format using V4L2_FIELD_ALTERNATE is not allowed since there * is no way you can pass the field information of each buffer to/from * userspace. A driver that supports this field format should check for * this in the queue_setup op and reject it if this function returns true. */
static inline bool vb2_fileio_is_active(struct vb2_queue *q) { return q->fileio; }

Contributors

PersonTokensPropCommitsCommitProp
hans verkuilhans verkuil17100.00%1100.00%
Total17100.00%1100.00%

/** * vb2_is_busy() - return busy status of the queue * @q: videobuf queue * * This function checks if queue has any buffers allocated. */
static inline bool vb2_is_busy(struct vb2_queue *q) { return (q->num_buffers > 0); }

Contributors

PersonTokensPropCommitsCommitProp
pawel osciakpawel osciak21100.00%1100.00%
Total21100.00%1100.00%

/** * vb2_get_drv_priv() - return driver private data associated with the queue * @q: videobuf queue */
static inline void *vb2_get_drv_priv(struct vb2_queue *q) { return q->drv_priv; }

Contributors

PersonTokensPropCommitsCommitProp
pawel osciakpawel osciak18100.00%1100.00%
Total18100.00%1100.00%

/** * vb2_set_plane_payload() - set bytesused for the plane plane_no * @vb: buffer for which plane payload should be set * @plane_no: plane number for which payload should be set * @size: payload in bytes */
static inline void vb2_set_plane_payload(struct vb2_buffer *vb, unsigned int plane_no, unsigned long size) { if (plane_no < vb->num_planes) vb->planes[plane_no].bytesused = size; }

Contributors

PersonTokensPropCommitsCommitProp
pawel osciakpawel osciak3897.44%150.00%
junghak sungjunghak sung12.56%150.00%
Total39100.00%2100.00%

/** * vb2_get_plane_payload() - get bytesused for the plane plane_no * @vb: buffer for which plane payload should be set * @plane_no: plane number for which payload should be set */
static inline unsigned long vb2_get_plane_payload(struct vb2_buffer *vb, unsigned int plane_no) { if (plane_no < vb->num_planes) return vb->planes[plane_no].bytesused; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
pawel osciakpawel osciak3797.37%150.00%
junghak sungjunghak sung12.63%150.00%
Total38100.00%2100.00%

/** * vb2_plane_size() - return plane size in bytes * @vb: buffer for which plane size should be returned * @plane_no: plane number for which size should be returned */
static inline unsigned long vb2_plane_size(struct vb2_buffer *vb, unsigned int plane_no) { if (plane_no < vb->num_planes) return vb->planes[plane_no].length; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
pawel osciakpawel osciak3797.37%150.00%
junghak sungjunghak sung12.63%150.00%
Total38100.00%2100.00%

/** * vb2_start_streaming_called() - return streaming status of driver * @q: videobuf queue */
static inline bool vb2_start_streaming_called(struct vb2_queue *q) { return q->start_streaming_called; }

Contributors

PersonTokensPropCommitsCommitProp
prabhakar ladprabhakar lad17100.00%1100.00%
Total17100.00%1100.00%

/** * vb2_clear_last_buffer_dequeued() - clear last buffer dequeued flag of queue * @q: videobuf queue */
static inline void vb2_clear_last_buffer_dequeued(struct vb2_queue *q) { q->last_buffer_dequeued = false; }

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philipp zabelphilipp zabel18100.00%1100.00%
Total18100.00%1100.00%

/* * The following functions are not part of the vb2 core API, but are useful * functions for videobuf2-*. */ bool vb2_buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb); int vb2_verify_memory_type(struct vb2_queue *q, enum vb2_memory memory, unsigned int type); #endif /* _MEDIA_VIDEOBUF2_CORE_H */

Overall Contributors

PersonTokensPropCommitsCommitProp
pawel osciakpawel osciak74645.40%11.92%
junghak sungjunghak sung40824.83%815.38%
hans verkuilhans verkuil19011.56%1936.54%
sumit semwalsumit semwal744.50%11.92%
marek szyprowskimarek szyprowski352.13%47.69%
scott jiangscott jiang311.89%11.92%
philipp zabelphilipp zabel291.77%23.85%
tomasz stanislawskitomasz stanislawski231.40%11.92%
laurent pinchartlaurent pinchart221.34%23.85%
sakari ailussakari ailus221.34%35.77%
guennadi liakhovetskiguennadi liakhovetski211.28%23.85%
prabhakar ladprabhakar lad181.10%11.92%
kamil debskikamil debski150.91%35.77%
ricardo ribaldaricardo ribalda60.37%11.92%
mauro carvalho chehabmauro carvalho chehab30.18%35.77%
Total1643100.00%52100.00%
Directory: include/media
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