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diff --git a/include/media/videobuf2-v4l2.h b/include/media/videobuf2-v4l2.h
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+/*
+ * videobuf2-v4l2.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_V4L2_H
+#define _MEDIA_VIDEOBUF2_V4L2_H
+
+#include <linux/videodev2.h>
+#include <media/videobuf2-core.h>
+
+#if VB2_MAX_FRAME != VIDEO_MAX_FRAME
+#error VB2_MAX_FRAME != VIDEO_MAX_FRAME
+#endif
+
+#if VB2_MAX_PLANES != VIDEO_MAX_PLANES
+#error VB2_MAX_PLANES != VIDEO_MAX_PLANES
+#endif
+
+struct video_device;
+
+/**
+ * struct vb2_v4l2_buffer - video buffer information for v4l2.
+ *
+ * @vb2_buf: embedded struct &vb2_buffer.
+ * @flags: buffer informational flags.
+ * @field: field order of the image in the buffer, as defined by
+ * &enum v4l2_field.
+ * @timecode: frame timecode.
+ * @sequence: sequence count of this frame.
+ * @request_fd: the request_fd associated with this buffer
+ * @is_held: if true, then this capture buffer was held
+ * @planes: plane information (userptr/fd, length, bytesused, data_offset).
+ *
+ * Should contain enough information to be able to cover all the fields
+ * of &struct v4l2_buffer at ``videodev2.h``.
+ */
+struct vb2_v4l2_buffer {
+ struct vb2_buffer vb2_buf;
+
+ __u32 flags;
+ __u32 field;
+ struct v4l2_timecode timecode;
+ __u32 sequence;
+ __s32 request_fd;
+ bool is_held;
+ struct vb2_plane planes[VB2_MAX_PLANES];
+};
+
+/* VB2 V4L2 flags as set in vb2_queue.subsystem_flags */
+#define VB2_V4L2_FL_SUPPORTS_M2M_HOLD_CAPTURE_BUF (1 << 0)
+
+/*
+ * to_vb2_v4l2_buffer() - cast struct vb2_buffer * to struct vb2_v4l2_buffer *
+ */
+#define to_vb2_v4l2_buffer(vb) \
+ container_of(vb, struct vb2_v4l2_buffer, vb2_buf)
+
+/**
+ * vb2_find_buffer() - Find a buffer with given timestamp
+ *
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @timestamp: the timestamp to find.
+ *
+ * Returns the buffer with the given @timestamp, or NULL if not found.
+ */
+struct vb2_buffer *vb2_find_buffer(struct vb2_queue *q, u64 timestamp);
+
+int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b);
+
+/**
+ * vb2_reqbufs() - Wrapper for vb2_core_reqbufs() that also verifies
+ * the memory and type values.
+ *
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @req: &struct v4l2_requestbuffers passed from userspace to
+ * &v4l2_ioctl_ops->vidioc_reqbufs handler in driver.
+ */
+int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req);
+
+/**
+ * vb2_create_bufs() - Wrapper for vb2_core_create_bufs() that also verifies
+ * the memory and type values.
+ *
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @create: creation parameters, passed from userspace to
+ * &v4l2_ioctl_ops->vidioc_create_bufs handler in driver
+ */
+int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create);
+
+/**
+ * vb2_prepare_buf() - Pass ownership of a buffer from userspace to the kernel
+ *
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @mdev: pointer to &struct media_device, may be NULL.
+ * @b: buffer structure passed from userspace to
+ * &v4l2_ioctl_ops->vidioc_prepare_buf handler in driver
+ *
+ * Should be called from &v4l2_ioctl_ops->vidioc_prepare_buf ioctl handler
+ * of a driver.
+ *
+ * This function:
+ *
+ * #) verifies the passed buffer,
+ * #) calls &vb2_ops->buf_prepare callback in the driver (if provided),
+ * in which driver-specific buffer initialization can be performed.
+ * #) if @b->request_fd is non-zero and @mdev->ops->req_queue is set,
+ * then bind the prepared buffer to the request.
+ *
+ * The return values from this function are intended to be directly returned
+ * from &v4l2_ioctl_ops->vidioc_prepare_buf handler in driver.
+ */
+int vb2_prepare_buf(struct vb2_queue *q, struct media_device *mdev,
+ struct v4l2_buffer *b);
+
+/**
+ * vb2_qbuf() - Queue a buffer from userspace
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @mdev: pointer to &struct media_device, may be NULL.
+ * @b: buffer structure passed from userspace to
+ * &v4l2_ioctl_ops->vidioc_qbuf handler in driver
+ *
+ * Should be called from &v4l2_ioctl_ops->vidioc_qbuf handler of a driver.
+ *
+ * This function:
+ *
+ * #) verifies the passed buffer;
+ * #) if @b->request_fd is non-zero and @mdev->ops->req_queue is set,
+ * then bind the buffer to the request.
+ * #) if necessary, calls &vb2_ops->buf_prepare callback in the driver
+ * (if provided), in which driver-specific buffer initialization can
+ * be performed;
+ * #) if streaming is on, queues the buffer in driver by the means of
+ * &vb2_ops->buf_queue callback for processing.
+ *
+ * The return values from this function are intended to be directly returned
+ * from &v4l2_ioctl_ops->vidioc_qbuf handler in driver.
+ */
+int vb2_qbuf(struct vb2_queue *q, struct media_device *mdev,
+ struct v4l2_buffer *b);
+
+/**
+ * vb2_expbuf() - Export a buffer as a file descriptor
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @eb: export buffer structure passed from userspace to
+ * &v4l2_ioctl_ops->vidioc_expbuf handler in driver
+ *
+ * The return values from this function are intended to be directly returned
+ * from &v4l2_ioctl_ops->vidioc_expbuf handler in driver.
+ */
+int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb);
+
+/**
+ * vb2_dqbuf() - Dequeue a buffer to the userspace
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @b: buffer structure passed from userspace to
+ * &v4l2_ioctl_ops->vidioc_dqbuf handler in driver
+ * @nonblocking: if true, this call will not sleep waiting for a buffer if no
+ * buffers ready for dequeuing are present. Normally the driver
+ * would be passing (&file->f_flags & %O_NONBLOCK) here
+ *
+ * Should be called from &v4l2_ioctl_ops->vidioc_dqbuf ioctl handler
+ * of a driver.
+ *
+ * This function:
+ *
+ * #) verifies the passed buffer;
+ * #) calls &vb2_ops->buf_finish callback in the driver (if provided), in which
+ * driver can perform any additional operations that may be required before
+ * returning the buffer to userspace, such as cache sync;
+ * #) the buffer struct members are filled with relevant information for
+ * the userspace.
+ *
+ * The return values from this function are intended to be directly returned
+ * from &v4l2_ioctl_ops->vidioc_dqbuf handler in driver.
+ */
+int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking);
+
+/**
+ * vb2_streamon - start streaming
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @type: type argument passed from userspace to vidioc_streamon handler,
+ * as defined by &enum v4l2_buf_type.
+ *
+ * Should be called from &v4l2_ioctl_ops->vidioc_streamon handler of a driver.
+ *
+ * This function:
+ *
+ * 1) verifies current state
+ * 2) passes any previously queued buffers to the driver and starts streaming
+ *
+ * The return values from this function are intended to be directly returned
+ * from &v4l2_ioctl_ops->vidioc_streamon handler in the driver.
+ */
+int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type);
+
+/**
+ * vb2_streamoff - stop streaming
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @type: type argument passed from userspace to vidioc_streamoff handler
+ *
+ * Should be called from vidioc_streamoff handler of a driver.
+ *
+ * This function:
+ *
+ * #) verifies current state,
+ * #) stop streaming and dequeues any queued buffers, including those previously
+ * passed to the driver (after waiting for the driver to finish).
+ *
+ * This call can be used for pausing playback.
+ * The return values from this function are intended to be directly returned
+ * from vidioc_streamoff handler in the driver
+ */
+int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type);
+
+/**
+ * vb2_queue_init() - initialize a videobuf2 queue
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ *
+ * The vb2_queue structure should be allocated by the driver. The driver is
+ * responsible of clearing it's content and setting initial values for some
+ * required entries before calling this function.
+ * q->ops, q->mem_ops, q->type and q->io_modes are mandatory. Please refer
+ * to the struct vb2_queue description in include/media/videobuf2-core.h
+ * for more information.
+ */
+int __must_check vb2_queue_init(struct vb2_queue *q);
+
+/**
+ * vb2_queue_init_name() - initialize a videobuf2 queue with a name
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @name: the queue name
+ *
+ * This function initializes the vb2_queue exactly like vb2_queue_init(),
+ * and additionally sets the queue name. The queue name is used for logging
+ * purpose, and should uniquely identify the queue within the context of the
+ * device it belongs to. This is useful to attribute kernel log messages to the
+ * right queue for m2m devices or other devices that handle multiple queues.
+ */
+int __must_check vb2_queue_init_name(struct vb2_queue *q, const char *name);
+
+/**
+ * vb2_queue_release() - stop streaming, release the queue and free memory
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ *
+ * This function stops streaming and performs necessary clean ups, including
+ * freeing video buffer memory. The driver is responsible for freeing
+ * the vb2_queue structure itself.
+ */
+void vb2_queue_release(struct vb2_queue *q);
+
+/**
+ * vb2_queue_change_type() - change the type of an inactive vb2_queue
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @type: the type to change to (V4L2_BUF_TYPE_VIDEO_*)
+ *
+ * This function changes the type of the vb2_queue. This is only possible
+ * if the queue is not busy (i.e. no buffers have been allocated).
+ *
+ * vb2_queue_change_type() can be used to support multiple buffer types using
+ * the same queue. The driver can implement v4l2_ioctl_ops.vidioc_reqbufs and
+ * v4l2_ioctl_ops.vidioc_create_bufs functions and call vb2_queue_change_type()
+ * before calling vb2_ioctl_reqbufs() or vb2_ioctl_create_bufs(), and thus
+ * "lock" the buffer type until the buffers have been released.
+ */
+int vb2_queue_change_type(struct vb2_queue *q, unsigned int type);
+
+/**
+ * vb2_poll() - implements poll userspace operation
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @file: file argument passed to the poll file operation handler
+ * @wait: wait argument passed to the poll file operation handler
+ *
+ * This function implements poll file operation handler for a driver.
+ * For CAPTURE queues, if a buffer is ready to be dequeued, the userspace will
+ * be informed that the file descriptor of a video device is available for
+ * reading.
+ * For OUTPUT queues, if a buffer is ready to be dequeued, the file descriptor
+ * will be reported as available for writing.
+ *
+ * If the driver uses struct v4l2_fh, then vb2_poll() will also check for any
+ * pending events.
+ *
+ * The return values from this function are intended to be directly returned
+ * from poll handler in driver.
+ */
+__poll_t vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait);
+
+/*
+ * The following functions are not part of the vb2 core API, but are simple
+ * helper functions that you can use in your struct v4l2_file_operations,
+ * struct v4l2_ioctl_ops and struct vb2_ops. They will serialize if vb2_queue->lock
+ * or video_device->lock is set, and they will set and test the queue owner
+ * (vb2_queue->owner) to check if the calling filehandle is permitted to do the
+ * queuing operation.
+ */
+
+/**
+ * vb2_queue_is_busy() - check if the queue is busy
+ * @q: pointer to &struct vb2_queue with videobuf2 queue.
+ * @file: file through which the vb2 queue access is performed
+ *
+ * The queue is considered busy if it has an owner and the owner is not the
+ * @file.
+ *
+ * Queue ownership is acquired and checked by some of the v4l2_ioctl_ops helpers
+ * below. Drivers can also use this function directly when they need to
+ * open-code ioctl handlers, for instance to add additional checks between the
+ * queue ownership test and the call to the corresponding vb2 operation.
+ */
+static inline bool vb2_queue_is_busy(struct vb2_queue *q, struct file *file)
+{
+ return q->owner && q->owner != file->private_data;
+}
+
+/* struct v4l2_ioctl_ops helpers */
+
+int vb2_ioctl_reqbufs(struct file *file, void *priv,
+ struct v4l2_requestbuffers *p);
+int vb2_ioctl_create_bufs(struct file *file, void *priv,
+ struct v4l2_create_buffers *p);
+int vb2_ioctl_prepare_buf(struct file *file, void *priv,
+ struct v4l2_buffer *p);
+int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p);
+int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p);
+int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p);
+int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i);
+int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i);
+int vb2_ioctl_expbuf(struct file *file, void *priv,
+ struct v4l2_exportbuffer *p);
+
+/* struct v4l2_file_operations helpers */
+
+int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma);
+int vb2_fop_release(struct file *file);
+int _vb2_fop_release(struct file *file, struct mutex *lock);
+ssize_t vb2_fop_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos);
+ssize_t vb2_fop_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos);
+__poll_t vb2_fop_poll(struct file *file, poll_table *wait);
+#ifndef CONFIG_MMU
+unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr,
+ unsigned long len, unsigned long pgoff, unsigned long flags);
+#endif
+
+/**
+ * vb2_video_unregister_device - unregister the video device and release queue
+ *
+ * @vdev: pointer to &struct video_device
+ *
+ * If the driver uses vb2_fop_release()/_vb2_fop_release(), then it should use
+ * vb2_video_unregister_device() instead of video_unregister_device().
+ *
+ * This function will call video_unregister_device() and then release the
+ * vb2_queue if streaming is in progress. This will stop streaming and
+ * this will simplify the unbind sequence since after this call all subdevs
+ * will have stopped streaming as well.
+ */
+void vb2_video_unregister_device(struct video_device *vdev);
+
+/**
+ * vb2_ops_wait_prepare - helper function to lock a struct &vb2_queue
+ *
+ * @vq: pointer to &struct vb2_queue
+ *
+ * ..note:: only use if vq->lock is non-NULL.
+ */
+void vb2_ops_wait_prepare(struct vb2_queue *vq);
+
+/**
+ * vb2_ops_wait_finish - helper function to unlock a struct &vb2_queue
+ *
+ * @vq: pointer to &struct vb2_queue
+ *
+ * ..note:: only use if vq->lock is non-NULL.
+ */
+void vb2_ops_wait_finish(struct vb2_queue *vq);
+
+struct media_request;
+int vb2_request_validate(struct media_request *req);
+void vb2_request_queue(struct media_request *req);
+
+#endif /* _MEDIA_VIDEOBUF2_V4L2_H */