There are several VB2 core functions that aren't documented. Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx> --- include/media/videobuf2-core.h | 54 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 53 insertions(+), 1 deletion(-) diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index e145f1475ffe..ce795cd0a7cc 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -786,7 +786,28 @@ 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); +/** + * vb2_core_streamon() - Implements VB2 stream ON logic + * + * @q: pointer to &struct vb2_queue with videobuf2 queue + * @type: type of the queue to be started. + * For V4L2, this is defined by &enum v4l2_buf_type type. + * + * Should be called from &v4l2_ioctl_ops->vidioc_streamon ioctl handler of + * a driver. + */ int vb2_core_streamon(struct vb2_queue *q, unsigned int type); + +/** + * vb2_core_streamoff() - Implements VB2 stream OFF logic + * + * @q: pointer to &struct vb2_queue with videobuf2 queue + * @type: type of the queue to be started. + * For V4L2, this is defined by &enum v4l2_buf_type type. + * + * Should be called from &v4l2_ioctl_ops->vidioc_streamon ioctl handler of + * a driver. + */ int vb2_core_streamoff(struct vb2_queue *q, unsigned int type); /** @@ -874,6 +895,21 @@ void vb2_queue_error(struct vb2_queue *q); int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma); #ifndef CONFIG_MMU +/** + * vb2_get_unmapped_area - map video buffers into application address space. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @addr: memory address. + * @len: buffer size. + * @pgoff: page offset. + * @flags: memory flags. + * + * This function is used in noMMU platforms to propose address mapping + * for a given buffer. It's intended to be used as a handler for the + * &file_operations->get_unmapped_area operation. + * + * This is called by the mmap() syscall routines will call this + * to get a proposed address for the mapping, when ``!CONFIG_MMU``. + */ unsigned long vb2_get_unmapped_area(struct vb2_queue *q, unsigned long addr, unsigned long len, @@ -882,7 +918,7 @@ unsigned long vb2_get_unmapped_area(struct vb2_queue *q, #endif /** - * vb2_core_poll() - implements poll userspace operation. + * vb2_core_poll() - implements poll syscall() logic. * @q: pointer to &struct vb2_queue with videobuf2 queue. * @file: &struct file argument passed to the poll * file operation handler. @@ -902,8 +938,24 @@ unsigned long vb2_get_unmapped_area(struct vb2_queue *q, unsigned int vb2_core_poll(struct vb2_queue *q, struct file *file, poll_table *wait); +/** + * vb2_read() - implements read() syscall logic. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @data: pointed to target userspace buffer + * @count: number of bytes to read + * @ppos: file handle position tracking pointer + * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) + */ size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count, loff_t *ppos, int nonblock); +/** + * vb2_read() - implements write() syscall logic. + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @data: pointed to target userspace buffer + * @count: number of bytes to write + * @ppos: file handle position tracking pointer + * @nonblock: mode selector (1 means blocking calls, 0 means nonblocking) + */ size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count, loff_t *ppos, int nonblock); -- 2.13.6
