Commit 8dcde47f authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab
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media: vb2-core: document remaining functions 



There are several VB2 core functions that aren't documented.

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
parent 2b141324

include/media/videobuf2-core.h

+53 −1
Original line number Original line Diff line number Diff line
@@ -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,

int vb2_core_dqbuf(struct vb2_queue *q, unsigned int *pindex, void *pb,

		   bool nonblocking);

		   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);

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);

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);

int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma);





#ifndef CONFIG_MMU

#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 vb2_get_unmapped_area(struct vb2_queue *q,

				    unsigned long addr,

				    unsigned long addr,

				    unsigned long len,

				    unsigned long len,
@@ -882,7 +918,7 @@ unsigned long vb2_get_unmapped_area(struct vb2_queue *q, 
#endif

#endif





/**

/**

 * vb2_core_poll() - implements poll userspace operation.

 * vb2_core_poll() - implements poll syscall() logic.

 * @q:		pointer to &struct vb2_queue with videobuf2 queue.

 * @q:		pointer to &struct vb2_queue with videobuf2 queue.

 * @file:	&struct file argument passed to the poll

 * @file:	&struct file argument passed to the poll

 *		file operation handler.

 *		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,

unsigned int vb2_core_poll(struct vb2_queue *q, struct file *file,

			   poll_table *wait);

			   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,

size_t vb2_read(struct vb2_queue *q, char __user *data, size_t count,

		loff_t *ppos, int nonblock);

		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,

size_t vb2_write(struct vb2_queue *q, const char __user *data, size_t count,

		loff_t *ppos, int nonblock);

		loff_t *ppos, int nonblock);