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Commit 24ade5b6 authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab
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[media] videobuf2-v4l2.h: get kernel-doc tags from C file 

There are several functions documented at the C file. Move
them to the header, as this is the one used to build the
media books.
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
parent 434b67c5
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Showing with 150 additions and 143 deletions
drivers/media/v4l2-core/videobuf2-v4l2.c
View file @ 24ade5b6
......@@ -483,13 +483,6 @@ int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b)
}
EXPORT_SYMBOL(vb2_querybuf);
/**
* vb2_reqbufs() - Wrapper for vb2_core_reqbufs() that also verifies
* the memory and type values.
* @q: videobuf2 queue
* @req: struct passed from userspace to vidioc_reqbufs handler
* in driver
*/
int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
{
int ret = vb2_verify_memory_type(q, req->memory, req->type);
......@@ -498,21 +491,6 @@ int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
}
EXPORT_SYMBOL_GPL(vb2_reqbufs);
/**
* vb2_prepare_buf() - Pass ownership of a buffer from userspace to the kernel
* @q: videobuf2 queue
* @b: buffer structure passed from userspace to vidioc_prepare_buf
* handler in driver
*
* Should be called from vidioc_prepare_buf ioctl handler of a driver.
* This function:
* 1) verifies the passed buffer,
* 2) calls buf_prepare callback in the driver (if provided), in which
* driver-specific buffer initialization can be performed,
*
* The return values from this function are intended to be directly returned
* from vidioc_prepare_buf handler in driver.
*/
int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b)
{
int ret;
......@@ -528,13 +506,6 @@ int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b)
}
EXPORT_SYMBOL_GPL(vb2_prepare_buf);
/**
* vb2_create_bufs() - Wrapper for vb2_core_create_bufs() that also verifies
* the memory and type values.
* @q: videobuf2 queue
* @create: creation parameters, passed from userspace to vidioc_create_bufs
* handler in driver
*/
int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
{
unsigned requested_planes = 1;
......@@ -586,23 +557,6 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
}
EXPORT_SYMBOL_GPL(vb2_create_bufs);
/**
* vb2_qbuf() - Queue a buffer from userspace
* @q: videobuf2 queue
* @b: buffer structure passed from userspace to vidioc_qbuf handler
* in driver
*
* Should be called from vidioc_qbuf ioctl handler of a driver.
* This function:
* 1) verifies the passed buffer,
* 2) if necessary, calls buf_prepare callback in the driver (if provided), in
* which driver-specific buffer initialization can be performed,
* 3) if streaming is on, queues the buffer in driver by the means of buf_queue
* callback for processing.
*
* The return values from this function are intended to be directly returned
* from vidioc_qbuf handler in driver.
*/
int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
{
int ret;
......@@ -617,27 +571,6 @@ int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b)
}
EXPORT_SYMBOL_GPL(vb2_qbuf);
/**
* vb2_dqbuf() - Dequeue a buffer to the userspace
* @q: videobuf2 queue
* @b: buffer structure passed from userspace to 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 vidioc_dqbuf ioctl handler of a driver.
* This function:
* 1) verifies the passed buffer,
* 2) calls 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,
* 3) 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 vidioc_dqbuf handler in driver.
*/
int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking)
{
int ret;
......@@ -664,19 +597,6 @@ int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking)
}
EXPORT_SYMBOL_GPL(vb2_dqbuf);
/**
* vb2_streamon - start streaming
* @q: videobuf2 queue
* @type: type argument passed from userspace to vidioc_streamon handler
*
* Should be called from 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 vidioc_streamon handler in the driver.
*/
int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type)
{
if (vb2_fileio_is_active(q)) {
......@@ -687,21 +607,6 @@ int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type)
}
EXPORT_SYMBOL_GPL(vb2_streamon);
/**
* vb2_streamoff - stop streaming
* @q: videobuf2 queue
* @type: type argument passed from userspace to vidioc_streamoff handler
*
* Should be called from vidioc_streamoff handler of a driver.
* This function:
* 1) verifies current state,
* 2) 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)
{
if (vb2_fileio_is_active(q)) {
......@@ -712,15 +617,6 @@ int vb2_streamoff(struct vb2_queue *q, enum v4l2_buf_type type)
}
EXPORT_SYMBOL_GPL(vb2_streamoff);
/**
* vb2_expbuf() - Export a buffer as a file descriptor
* @q: videobuf2 queue
* @eb: export buffer structure passed from userspace to vidioc_expbuf
* handler in driver
*
* The return values from this function are intended to be directly returned
* from vidioc_expbuf handler in driver.
*/
int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb)
{
return vb2_core_expbuf(q, &eb->fd, eb->type, eb->index,
......@@ -728,17 +624,6 @@ int vb2_expbuf(struct vb2_queue *q, struct v4l2_exportbuffer *eb)
}
EXPORT_SYMBOL_GPL(vb2_expbuf);
/**
* vb2_queue_init() - initialize a videobuf2 queue
* @q: videobuf2 queue; this structure should be allocated in driver
*
* 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 vb2_queue_init(struct vb2_queue *q)
{
/*
......@@ -779,39 +664,12 @@ int vb2_queue_init(struct vb2_queue *q)
}
EXPORT_SYMBOL_GPL(vb2_queue_init);
/**
* vb2_queue_release() - stop streaming, release the queue and free memory
* @q: 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_core_queue_release(q);
}
EXPORT_SYMBOL_GPL(vb2_queue_release);
/**
* vb2_poll() - implements poll userspace operation
* @q: 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.
*/
unsigned int vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait)
{
struct video_device *vfd = video_devdata(file);
......
include/media/videobuf2-v4l2.h
View file @ 24ade5b6
......@@ -49,22 +49,171 @@ struct vb2_v4l2_buffer {
container_of(vb, struct vb2_v4l2_buffer, vb2_buf)
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: videobuf2 queue
* @req: struct passed from userspace to 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: videobuf2 queue
* @create: creation parameters, passed from userspace to 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: videobuf2 queue
* @b: buffer structure passed from userspace to vidioc_prepare_buf
* handler in driver
*
* Should be called from vidioc_prepare_buf ioctl handler of a driver.
* This function:
* 1) verifies the passed buffer,
* 2) calls buf_prepare callback in the driver (if provided), in which
* driver-specific buffer initialization can be performed,
*
* The return values from this function are intended to be directly returned
* from vidioc_prepare_buf handler in driver.
*/
int vb2_prepare_buf(struct vb2_queue *q, struct v4l2_buffer *b);
/**
* vb2_qbuf() - Queue a buffer from userspace
* @q: videobuf2 queue
* @b: buffer structure passed from userspace to vidioc_qbuf handler
* in driver
*
* Should be called from vidioc_qbuf ioctl handler of a driver.
* This function:
* 1) verifies the passed buffer,
* 2) if necessary, calls buf_prepare callback in the driver (if provided), in
* which driver-specific buffer initialization can be performed,
* 3) if streaming is on, queues the buffer in driver by the means of buf_queue
* callback for processing.
*
* The return values from this function are intended to be directly returned
* from vidioc_qbuf handler in driver.
*/
int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b);
/**
* vb2_expbuf() - Export a buffer as a file descriptor
* @q: videobuf2 queue
* @eb: export buffer structure passed from userspace to vidioc_expbuf
* handler in driver
*
* The return values from this function are intended to be directly returned
* from 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: videobuf2 queue
* @b: buffer structure passed from userspace to 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 vidioc_dqbuf ioctl handler of a driver.
* This function:
* 1) verifies the passed buffer,
* 2) calls 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,
* 3) 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 vidioc_dqbuf handler in driver.
*/
int vb2_dqbuf(struct vb2_queue *q, struct v4l2_buffer *b, bool nonblocking);
/**
* vb2_streamon - start streaming
* @q: videobuf2 queue
* @type: type argument passed from userspace to vidioc_streamon handler
*
* Should be called from 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 vidioc_streamon handler in the driver.
*/
int vb2_streamon(struct vb2_queue *q, enum v4l2_buf_type type);
/**
* vb2_streamoff - stop streaming
* @q: videobuf2 queue
* @type: type argument passed from userspace to vidioc_streamoff handler
*
* Should be called from vidioc_streamoff handler of a driver.
* This function:
* 1) verifies current state,
* 2) 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: videobuf2 queue; this structure should be allocated in driver
*
* 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_release() - stop streaming, release the queue and free memory
* @q: 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_poll() - implements poll userspace operation
* @q: 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.
*/
unsigned int vb2_poll(struct vb2_queue *q, struct file *file,
poll_table *wait);
poll_table *wait);
/*
* The following functions are not part of the vb2 core API, but are simple
......
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