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diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
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+++ b/include/media/videobuf2-core.h
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+/*
+ * 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;
+        int                     mapped:1;
+};
+
+/**
+ * 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
+ * @num_planes_mapped:  number of mapped planes; 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];
+        unsigned int            num_planes_mapped;
+};
+
+/**
+ * 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 before entering 'streaming' state; enables
+ *                      driver to receive buffers over buf_queue() callback
+ * @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
+ */
+struct vb2_ops {
+        int (*queue_setup)(struct vb2_queue *q, unsigned int *num_buffers,
+                           unsigned int *num_planes, unsigned long 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);
+        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                    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 */