include/media/videobuf2-core.h - kernel/msm-4.9 - Gitiles

 /*
  * videobuf2-core.h - V4L2 driver helper 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/videodev2.h>

 struct vb2_alloc_ctx;
 struct vb2_fileio_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
  * @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_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
  * @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
  */
 struct vb2_mem_ops {
 	void		*(*alloc)(void *alloc_ctx, unsigned long size);
 	void		(*put)(void *buf_priv);

 	void		*(*get_userptr)(void *alloc_ctx, unsigned long vaddr,
 					unsigned long size, int write);
 	void		(*put_userptr)(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 {
 	void			*mem_priv;
 };

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

 /**
  * enum vb2_fileio_flags - flags for selecting a mode of the file io emulator,
  * by default the 'streaming' style is used by the file io emulator
  * @VB2_FILEIO_READ_ONCE:	report EOF after reading the first buffer
  * @VB2_FILEIO_WRITE_IMMEDIATELY:	queue buffer after each write() call
  */
 enum vb2_fileio_flags {
 	VB2_FILEIO_READ_ONCE		= (1 << 0),
 	VB2_FILEIO_WRITE_IMMEDIATELY	= (1 << 1),
 };

 /**
  * enum vb2_buffer_state - current video buffer state
  * @VB2_BUF_STATE_DEQUEUED:	buffer under userspace control
  * @VB2_BUF_STATE_QUEUED:	buffer queued in videobuf, but not in 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_QUEUED,
 	VB2_BUF_STATE_ACTIVE,
 	VB2_BUF_STATE_DONE,
 	VB2_BUF_STATE_ERROR,
 };

 struct vb2_queue;

 /**
  * struct vb2_buffer - represents a video buffer
  * @v4l2_buf:		struct v4l2_buffer associated with this buffer; can
  *			be read by the driver and relevant entries can be
  *			changed by the driver in case of CAPTURE types
  *			(such as timestamp)
  * @v4l2_planes:	struct v4l2_planes associated with this buffer; can
  *			be read by the driver and relevant entries can be
  *			changed by the driver in case of CAPTURE types
  *			(such as bytesused); NOTE that even for single-planar
  *			types, the v4l2_planes[0] struct should be used
  *			instead of v4l2_buf for filling bytesused - drivers
  *			should use the vb2_set_plane_payload() function for that
  * @vb2_queue:		the queue to which this driver belongs
  * @num_planes:		number of planes in the buffer
  *			on an internal driver queue
  * @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
  * @planes:		private per-plane information; do not change
  */
 struct vb2_buffer {
 	struct v4l2_buffer	v4l2_buf;
 	struct v4l2_plane	v4l2_planes[VIDEO_MAX_PLANES];

 	struct vb2_queue	*vb2_queue;

 	unsigned int		num_planes;

 /* Private: internal use only */
 	enum vb2_buffer_state	state;

 	struct list_head	queued_entry;
 	struct list_head	done_entry;

 	struct vb2_plane	planes[VIDEO_MAX_PLANES];
 };

 /**
  * struct vb2_ops - driver-specific callbacks
  *
  * @queue_setup:	called from a VIDIOC_REQBUFS handler, before
  *			memory allocation; 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 alloc_ctxs[]
  *			array
  * @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;
  *			drivers may perform any initialization required before
  *			each hardware operation in this callback;
  *			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; drivers may perform any operations required
  *			before userspace accesses the buffer; optional
  * @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 or not enough
  *			buffers has been queued, in such case all buffers that
  *			have been already given by the @buf_queue callback are
  *			invalidated.
  * @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; 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);
 	int (*buf_finish)(struct vb2_buffer *vb);
 	void (*buf_cleanup)(struct vb2_buffer *vb);

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

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

 /**
  * struct vb2_queue - a videobuf queue
  *
  * @type:	queue type (see V4L2_BUF_TYPE_* in linux/videodev2.h
  * @io_modes:	supported io methods (see vb2_io_modes enum)
  * @io_flags:	additional io flags (see vb2_fileio_flags enum)
  * @ops:	driver-specific callbacks
  * @mem_ops:	memory allocator specific callbacks
  * @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, so sizeof(struct vb2_buffer) will is used
  *
  * @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 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
  * @fileio:	file io emulator internal data, used only if emulator is active
  */
 struct vb2_queue {
 	enum v4l2_buf_type		type;
 	unsigned int			io_modes;
 	unsigned int			io_flags;

 	const struct vb2_ops		*ops;
 	const struct vb2_mem_ops	*mem_ops;
 	void				*drv_priv;
 	unsigned int			buf_struct_size;

 /* private: internal use only */
 	enum v4l2_memory		memory;
 	struct vb2_buffer		*bufs[VIDEO_MAX_FRAME];
 	unsigned int			num_buffers;

 	struct list_head		queued_list;

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

 	void				*alloc_ctx[VIDEO_MAX_PLANES];
 	unsigned int			plane_sizes[VIDEO_MAX_PLANES];

 	unsigned int			streaming:1;

 	struct vb2_fileio_data		*fileio;
 };

 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);
 int vb2_wait_for_all_buffers(struct vb2_queue *q);

 int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b);
 int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req);

 int vb2_queue_init(struct vb2_queue *q);

 void vb2_queue_release(struct vb2_queue *q);

 int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b);
 int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking);

 int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type);
 int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type);

 int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma);
 unsigned int vb2_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, char __user *data, size_t count,
 		loff_t *ppos, int nonblock);

 /**
  * 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;
 }

 /**
  * 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);
 }

 /**
  * 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;
 }

 /**
  * 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->v4l2_planes[plane_no].bytesused = size;
 }

 /**
  * 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
  * @size:	payload in bytes
  */
 static inline unsigned long vb2_get_plane_payload(struct vb2_buffer *vb,
 				 unsigned int plane_no)
 {
 	if (plane_no < vb->num_planes)
 		return vb->v4l2_planes[plane_no].bytesused;
 	return 0;
 }

 /**
  * 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->v4l2_planes[plane_no].length;
 	return 0;
 }

 #endif /* _MEDIA_VIDEOBUF2_CORE_H */
	/*
	* videobuf2-core.h - V4L2 driver helper 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/videodev2.h>

	struct vb2_alloc_ctx;
	struct vb2_fileio_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
	* @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_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
	* @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
	*/
	struct vb2_mem_ops {
	void (alloc)(void *alloc_ctx, unsigned long size);
	void (put)(void buf_priv);

	void (get_userptr)(void *alloc_ctx, unsigned long vaddr,
	unsigned long size, int write);
	void (put_userptr)(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 {
	void *mem_priv;
	};

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

	/**
	* enum vb2_fileio_flags - flags for selecting a mode of the file io emulator,
	* by default the 'streaming' style is used by the file io emulator
	* @VB2_FILEIO_READ_ONCE: report EOF after reading the first buffer
	* @VB2_FILEIO_WRITE_IMMEDIATELY: queue buffer after each write() call
	*/
	enum vb2_fileio_flags {
	VB2_FILEIO_READ_ONCE = (1 << 0),
	VB2_FILEIO_WRITE_IMMEDIATELY = (1 << 1),
	};

	/**
	* enum vb2_buffer_state - current video buffer state
	* @VB2_BUF_STATE_DEQUEUED: buffer under userspace control
	* @VB2_BUF_STATE_QUEUED: buffer queued in videobuf, but not in 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_QUEUED,
	VB2_BUF_STATE_ACTIVE,
	VB2_BUF_STATE_DONE,
	VB2_BUF_STATE_ERROR,
	};

	struct vb2_queue;

	/**
	* struct vb2_buffer - represents a video buffer
	* @v4l2_buf: struct v4l2_buffer associated with this buffer; can
	* be read by the driver and relevant entries can be
	* changed by the driver in case of CAPTURE types
	* (such as timestamp)
	* @v4l2_planes: struct v4l2_planes associated with this buffer; can
	* be read by the driver and relevant entries can be
	* changed by the driver in case of CAPTURE types
	* (such as bytesused); NOTE that even for single-planar
	* types, the v4l2_planes[0] struct should be used
	* instead of v4l2_buf for filling bytesused - drivers
	* should use the vb2_set_plane_payload() function for that
	* @vb2_queue: the queue to which this driver belongs
	* @num_planes: number of planes in the buffer
	* on an internal driver queue
	* @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
	* @planes: private per-plane information; do not change
	*/
	struct vb2_buffer {
	struct v4l2_buffer v4l2_buf;
	struct v4l2_plane v4l2_planes[VIDEO_MAX_PLANES];

	struct vb2_queue *vb2_queue;

	unsigned int num_planes;

	/* Private: internal use only */
	enum vb2_buffer_state state;

	struct list_head queued_entry;
	struct list_head done_entry;

	struct vb2_plane planes[VIDEO_MAX_PLANES];
	};

	/**
	* struct vb2_ops - driver-specific callbacks
	*
	* @queue_setup: called from a VIDIOC_REQBUFS handler, before
	* memory allocation; 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 alloc_ctxs[]
	* array
	* @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;
	* drivers may perform any initialization required before
	* each hardware operation in this callback;
	* 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; drivers may perform any operations required
	* before userspace accesses the buffer; optional
	* @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 or not enough
	* buffers has been queued, in such case all buffers that
	* have been already given by the @buf_queue callback are
	* invalidated.
	* @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; 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);
	int (buf_finish)(struct vb2_buffer vb);
	void (buf_cleanup)(struct vb2_buffer vb);

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

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

	/**
	* struct vb2_queue - a videobuf queue
	*
	* @type: queue type (see V4L2_BUF_TYPE_* in linux/videodev2.h
	* @io_modes: supported io methods (see vb2_io_modes enum)
	* @io_flags: additional io flags (see vb2_fileio_flags enum)
	* @ops: driver-specific callbacks
	* @mem_ops: memory allocator specific callbacks
	* @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, so sizeof(struct vb2_buffer) will is used
	*
	* @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 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
	* @fileio: file io emulator internal data, used only if emulator is active
	*/
	struct vb2_queue {
	enum v4l2_buf_type type;
	unsigned int io_modes;
	unsigned int io_flags;

	const struct vb2_ops *ops;
	const struct vb2_mem_ops *mem_ops;
	void *drv_priv;
	unsigned int buf_struct_size;

	/* private: internal use only */
	enum v4l2_memory memory;
	struct vb2_buffer *bufs[VIDEO_MAX_FRAME];
	unsigned int num_buffers;

	struct list_head queued_list;

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

	void *alloc_ctx[VIDEO_MAX_PLANES];
	unsigned int plane_sizes[VIDEO_MAX_PLANES];

	unsigned int streaming:1;

	struct vb2_fileio_data *fileio;
	};

	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);
	int vb2_wait_for_all_buffers(struct vb2_queue *q);

	int vb2_querybuf(struct vb2_queue q, struct v4l2_buffer b);
	int vb2_reqbufs(struct vb2_queue q, struct v4l2_requestbuffers req);

	int vb2_queue_init(struct vb2_queue *q);

	void vb2_queue_release(struct vb2_queue *q);

	int vb2_qbuf(struct vb2_queue q, struct v4l2_buffer b);
	int vb2_dqbuf(struct vb2_queue q, struct v4l2_buffer b, bool nonblocking);

	int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type);
	int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type);

	int vb2_mmap(struct vb2_queue q, struct vm_area_struct vma);
	unsigned int vb2_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, char __user data, size_t count,
	loff_t *ppos, int nonblock);

	/**
	* 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;
	}

	/**
	* 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);
	}

	/**
	* 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;
	}

	/**
	* 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->v4l2_planes[plane_no].bytesused = size;
	}

	/**
	* 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
	* @size: payload in bytes
	*/
	static inline unsigned long vb2_get_plane_payload(struct vb2_buffer *vb,
	unsigned int plane_no)
	{
	if (plane_no < vb->num_planes)
	return vb->v4l2_planes[plane_no].bytesused;
	return 0;
	}

	/**
	* 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->v4l2_planes[plane_no].length;
	return 0;
	}

	#endif /* _MEDIA_VIDEOBUF2_CORE_H */