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1273 lines
49 KiB
1273 lines
49 KiB
/* |
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* videobuf2-core.h - Video Buffer 2 Core Framework |
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* |
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* Copyright (C) 2010 Samsung Electronics |
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* |
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* Author: Pawel Osciak <[email protected]> |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License as published by |
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* the Free Software Foundation. |
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*/ |
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#ifndef _MEDIA_VIDEOBUF2_CORE_H |
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#define _MEDIA_VIDEOBUF2_CORE_H |
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|
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#include <linux/mm_types.h> |
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#include <linux/mutex.h> |
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#include <linux/poll.h> |
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#include <linux/dma-buf.h> |
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#include <linux/bitops.h> |
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#include <media/media-request.h> |
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#include <media/frame_vector.h> |
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#define VB2_MAX_FRAME (32) |
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#define VB2_MAX_PLANES (8) |
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/** |
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* enum vb2_memory - type of memory model used to make the buffers visible |
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* on userspace. |
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* |
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* @VB2_MEMORY_UNKNOWN: Buffer status is unknown or it is not used yet on |
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* userspace. |
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* @VB2_MEMORY_MMAP: The buffers are allocated by the Kernel and it is |
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* memory mapped via mmap() ioctl. This model is |
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* also used when the user is using the buffers via |
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* read() or write() system calls. |
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* @VB2_MEMORY_USERPTR: The buffers was allocated in userspace and it is |
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* memory mapped via mmap() ioctl. |
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* @VB2_MEMORY_DMABUF: The buffers are passed to userspace via DMA buffer. |
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*/ |
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enum vb2_memory { |
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VB2_MEMORY_UNKNOWN = 0, |
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VB2_MEMORY_MMAP = 1, |
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VB2_MEMORY_USERPTR = 2, |
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VB2_MEMORY_DMABUF = 4, |
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}; |
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struct vb2_fileio_data; |
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struct vb2_threadio_data; |
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/** |
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* struct vb2_mem_ops - memory handling/memory allocator operations. |
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* @alloc: allocate video memory and, optionally, allocator private data, |
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* return ERR_PTR() on failure or a pointer to allocator private, |
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* per-buffer data on success; the returned private structure |
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* will then be passed as @buf_priv argument to other ops in this |
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* structure. Additional gfp_flags to use when allocating the |
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* are also passed to this operation. These flags are from the |
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* gfp_flags field of vb2_queue. The size argument to this function |
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* shall be *page aligned*. |
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* @put: inform the allocator that the buffer will no longer be used; |
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* usually will result in the allocator freeing the buffer (if |
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* no other users of this buffer are present); the @buf_priv |
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* argument is the allocator private per-buffer structure |
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* previously returned from the alloc callback. |
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* @get_dmabuf: acquire userspace memory for a hardware operation; used for |
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* DMABUF memory types. |
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* @get_userptr: acquire userspace memory for a hardware operation; used for |
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* USERPTR memory types; vaddr is the address passed to the |
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* videobuf layer when queuing a video buffer of USERPTR type; |
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* should return an allocator private per-buffer structure |
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* associated with the buffer on success, ERR_PTR() on failure; |
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* the returned private structure will then be passed as @buf_priv |
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* argument to other ops in this structure. |
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* @put_userptr: inform the allocator that a USERPTR buffer will no longer |
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* be used. |
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* @attach_dmabuf: attach a shared &struct dma_buf for a hardware operation; |
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* used for DMABUF memory types; dev is the alloc device |
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* dbuf is the shared dma_buf; returns ERR_PTR() on failure; |
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* allocator private per-buffer structure on success; |
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* this needs to be used for further accesses to the buffer. |
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* @detach_dmabuf: inform the exporter of the buffer that the current DMABUF |
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* buffer is no longer used; the @buf_priv argument is the |
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* allocator private per-buffer structure previously returned |
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* from the attach_dmabuf callback. |
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* @map_dmabuf: request for access to the dmabuf from allocator; the allocator |
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* of dmabuf is informed that this driver is going to use the |
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* dmabuf. |
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* @unmap_dmabuf: releases access control to the dmabuf - allocator is notified |
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* that this driver is done using the dmabuf for now. |
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* @prepare: called every time the buffer is passed from userspace to the |
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* driver, useful for cache synchronisation, optional. |
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* @finish: called every time the buffer is passed back from the driver |
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* to the userspace, also optional. |
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* @vaddr: return a kernel virtual address to a given memory buffer |
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* associated with the passed private structure or NULL if no |
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* such mapping exists. |
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* @cookie: return allocator specific cookie for a given memory buffer |
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* associated with the passed private structure or NULL if not |
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* available. |
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* @num_users: return the current number of users of a memory buffer; |
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* return 1 if the videobuf layer (or actually the driver using |
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* it) is the only user. |
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* @mmap: setup a userspace mapping for a given memory buffer under |
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* the provided virtual memory region. |
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* |
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* Those operations are used by the videobuf2 core to implement the memory |
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* handling/memory allocators for each type of supported streaming I/O method. |
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* |
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* .. note:: |
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* #) Required ops for USERPTR types: get_userptr, put_userptr. |
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* |
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* #) Required ops for MMAP types: alloc, put, num_users, mmap. |
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* |
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* #) Required ops for read/write access types: alloc, put, num_users, vaddr. |
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* |
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* #) Required ops for DMABUF types: attach_dmabuf, detach_dmabuf, |
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* map_dmabuf, unmap_dmabuf. |
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*/ |
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struct vb2_mem_ops { |
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void *(*alloc)(struct device *dev, unsigned long attrs, |
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unsigned long size, |
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enum dma_data_direction dma_dir, |
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gfp_t gfp_flags); |
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void (*put)(void *buf_priv); |
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struct dma_buf *(*get_dmabuf)(void *buf_priv, unsigned long flags); |
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void *(*get_userptr)(struct device *dev, unsigned long vaddr, |
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unsigned long size, |
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enum dma_data_direction dma_dir); |
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void (*put_userptr)(void *buf_priv); |
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void (*prepare)(void *buf_priv); |
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void (*finish)(void *buf_priv); |
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void *(*attach_dmabuf)(struct device *dev, |
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struct dma_buf *dbuf, |
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unsigned long size, |
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enum dma_data_direction dma_dir); |
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void (*detach_dmabuf)(void *buf_priv); |
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int (*map_dmabuf)(void *buf_priv); |
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void (*unmap_dmabuf)(void *buf_priv); |
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void *(*vaddr)(void *buf_priv); |
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void *(*cookie)(void *buf_priv); |
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unsigned int (*num_users)(void *buf_priv); |
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int (*mmap)(void *buf_priv, struct vm_area_struct *vma); |
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}; |
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/** |
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* struct vb2_plane - plane information. |
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* @mem_priv: private data with this plane. |
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* @dbuf: dma_buf - shared buffer object. |
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* @dbuf_mapped: flag to show whether dbuf is mapped or not |
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* @bytesused: number of bytes occupied by data in the plane (payload). |
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* @length: size of this plane (NOT the payload) in bytes. |
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* @min_length: minimum required size of this plane (NOT the payload) in bytes. |
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* @length is always greater or equal to @min_length. |
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* @m: Union with memtype-specific data. |
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* @m.offset: when memory in the associated struct vb2_buffer is |
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* %VB2_MEMORY_MMAP, equals the offset from the start of |
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* the device memory for this plane (or is a "cookie" that |
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* should be passed to mmap() called on the video node). |
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* @m.userptr: when memory is %VB2_MEMORY_USERPTR, a userspace pointer |
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* pointing to this plane. |
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* @m.fd: when memory is %VB2_MEMORY_DMABUF, a userspace file |
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* descriptor associated with this plane. |
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* @data_offset: offset in the plane to the start of data; usually 0, |
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* unless there is a header in front of the data. |
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* |
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* Should contain enough information to be able to cover all the fields |
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* of &struct v4l2_plane at videodev2.h. |
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*/ |
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struct vb2_plane { |
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void *mem_priv; |
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struct dma_buf *dbuf; |
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unsigned int dbuf_mapped; |
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unsigned int bytesused; |
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unsigned int length; |
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unsigned int min_length; |
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union { |
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unsigned int offset; |
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unsigned long userptr; |
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int fd; |
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} m; |
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unsigned int data_offset; |
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}; |
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/** |
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* enum vb2_io_modes - queue access methods. |
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* @VB2_MMAP: driver supports MMAP with streaming API. |
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* @VB2_USERPTR: driver supports USERPTR with streaming API. |
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* @VB2_READ: driver supports read() style access. |
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* @VB2_WRITE: driver supports write() style access. |
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* @VB2_DMABUF: driver supports DMABUF with streaming API. |
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*/ |
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enum vb2_io_modes { |
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VB2_MMAP = BIT(0), |
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VB2_USERPTR = BIT(1), |
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VB2_READ = BIT(2), |
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VB2_WRITE = BIT(3), |
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VB2_DMABUF = BIT(4), |
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}; |
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/** |
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* enum vb2_buffer_state - current video buffer state. |
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* @VB2_BUF_STATE_DEQUEUED: buffer under userspace control. |
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* @VB2_BUF_STATE_IN_REQUEST: buffer is queued in media request. |
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* @VB2_BUF_STATE_PREPARING: buffer is being prepared in videobuf. |
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* @VB2_BUF_STATE_QUEUED: buffer queued in videobuf, but not in driver. |
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* @VB2_BUF_STATE_ACTIVE: buffer queued in driver and possibly used |
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* in a hardware operation. |
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* @VB2_BUF_STATE_DONE: buffer returned from driver to videobuf, but |
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* not yet dequeued to userspace. |
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* @VB2_BUF_STATE_ERROR: same as above, but the operation on the buffer |
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* has ended with an error, which will be reported |
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* to the userspace when it is dequeued. |
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*/ |
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enum vb2_buffer_state { |
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VB2_BUF_STATE_DEQUEUED, |
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VB2_BUF_STATE_IN_REQUEST, |
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VB2_BUF_STATE_PREPARING, |
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VB2_BUF_STATE_QUEUED, |
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VB2_BUF_STATE_ACTIVE, |
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VB2_BUF_STATE_DONE, |
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VB2_BUF_STATE_ERROR, |
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}; |
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struct vb2_queue; |
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/** |
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* struct vb2_buffer - represents a video buffer. |
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* @vb2_queue: pointer to &struct vb2_queue with the queue to |
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* which this driver belongs. |
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* @index: id number of the buffer. |
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* @type: buffer type. |
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* @memory: the method, in which the actual data is passed. |
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* @num_planes: number of planes in the buffer |
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* on an internal driver queue. |
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* @timestamp: frame timestamp in ns. |
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* @request: the request this buffer is associated with. |
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* @req_obj: used to bind this buffer to a request. This |
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* request object has a refcount. |
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*/ |
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struct vb2_buffer { |
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struct vb2_queue *vb2_queue; |
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unsigned int index; |
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unsigned int type; |
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unsigned int memory; |
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unsigned int num_planes; |
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u64 timestamp; |
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struct media_request *request; |
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struct media_request_object req_obj; |
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/* private: internal use only |
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* |
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* state: current buffer state; do not change |
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* synced: this buffer has been synced for DMA, i.e. the |
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* 'prepare' memop was called. It is cleared again |
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* after the 'finish' memop is called. |
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* prepared: this buffer has been prepared, i.e. the |
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* buf_prepare op was called. It is cleared again |
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* after the 'buf_finish' op is called. |
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* copied_timestamp: the timestamp of this capture buffer was copied |
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* from an output buffer. |
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* need_cache_sync_on_prepare: when set buffer's ->prepare() function |
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* performs cache sync/invalidation. |
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* need_cache_sync_on_finish: when set buffer's ->finish() function |
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* performs cache sync/invalidation. |
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* queued_entry: entry on the queued buffers list, which holds |
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* all buffers queued from userspace |
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* done_entry: entry on the list that stores all buffers ready |
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* to be dequeued to userspace |
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* vb2_plane: per-plane information; do not change |
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*/ |
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enum vb2_buffer_state state; |
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unsigned int synced:1; |
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unsigned int prepared:1; |
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unsigned int copied_timestamp:1; |
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unsigned int need_cache_sync_on_prepare:1; |
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unsigned int need_cache_sync_on_finish:1; |
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struct vb2_plane planes[VB2_MAX_PLANES]; |
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struct list_head queued_entry; |
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struct list_head done_entry; |
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#ifdef CONFIG_VIDEO_ADV_DEBUG |
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/* |
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* Counters for how often these buffer-related ops are |
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* called. Used to check for unbalanced ops. |
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*/ |
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u32 cnt_mem_alloc; |
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u32 cnt_mem_put; |
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u32 cnt_mem_get_dmabuf; |
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u32 cnt_mem_get_userptr; |
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u32 cnt_mem_put_userptr; |
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u32 cnt_mem_prepare; |
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u32 cnt_mem_finish; |
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u32 cnt_mem_attach_dmabuf; |
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u32 cnt_mem_detach_dmabuf; |
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u32 cnt_mem_map_dmabuf; |
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u32 cnt_mem_unmap_dmabuf; |
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u32 cnt_mem_vaddr; |
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u32 cnt_mem_cookie; |
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u32 cnt_mem_num_users; |
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u32 cnt_mem_mmap; |
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u32 cnt_buf_out_validate; |
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u32 cnt_buf_init; |
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u32 cnt_buf_prepare; |
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u32 cnt_buf_finish; |
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u32 cnt_buf_cleanup; |
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u32 cnt_buf_queue; |
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u32 cnt_buf_request_complete; |
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/* This counts the number of calls to vb2_buffer_done() */ |
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u32 cnt_buf_done; |
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#endif |
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}; |
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/** |
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* struct vb2_ops - driver-specific callbacks. |
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* |
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* These operations are not called from interrupt context except where |
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* mentioned specifically. |
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* |
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* @queue_setup: called from VIDIOC_REQBUFS() and VIDIOC_CREATE_BUFS() |
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* handlers before memory allocation. It can be called |
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* twice: if the original number of requested buffers |
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* could not be allocated, then it will be called a |
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* second time with the actually allocated number of |
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* buffers to verify if that is OK. |
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* The driver should return the required number of buffers |
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* in \*num_buffers, the required number of planes per |
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* buffer in \*num_planes, the size of each plane should be |
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* set in the sizes\[\] array and optional per-plane |
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* allocator specific device in the alloc_devs\[\] array. |
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* When called from VIDIOC_REQBUFS(), \*num_planes == 0, |
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* the driver has to use the currently configured format to |
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* determine the plane sizes and \*num_buffers is the total |
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* number of buffers that are being allocated. When called |
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* from VIDIOC_CREATE_BUFS(), \*num_planes != 0 and it |
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* describes the requested number of planes and sizes\[\] |
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* contains the requested plane sizes. In this case |
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* \*num_buffers are being allocated additionally to |
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* q->num_buffers. If either \*num_planes or the requested |
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* sizes are invalid callback must return %-EINVAL. |
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* @wait_prepare: release any locks taken while calling vb2 functions; |
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* it is called before an ioctl needs to wait for a new |
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* buffer to arrive; required to avoid a deadlock in |
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* blocking access type. |
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* @wait_finish: reacquire all locks released in the previous callback; |
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* required to continue operation after sleeping while |
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* waiting for a new buffer to arrive. |
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* @buf_out_validate: called when the output buffer is prepared or queued |
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* to a request; drivers can use this to validate |
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* userspace-provided information; this is required only |
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* for OUTPUT queues. |
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* @buf_init: called once after allocating a buffer (in MMAP case) |
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* or after acquiring a new USERPTR buffer; drivers may |
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* perform additional buffer-related initialization; |
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* initialization failure (return != 0) will prevent |
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* queue setup from completing successfully; optional. |
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* @buf_prepare: called every time the buffer is queued from userspace |
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* and from the VIDIOC_PREPARE_BUF() ioctl; drivers may |
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* perform any initialization required before each |
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* hardware operation in this callback; drivers can |
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* access/modify the buffer here as it is still synced for |
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* the CPU; drivers that support VIDIOC_CREATE_BUFS() must |
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* also validate the buffer size; if an error is returned, |
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* the buffer will not be queued in driver; optional. |
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* @buf_finish: called before every dequeue of the buffer back to |
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* userspace; the buffer is synced for the CPU, so drivers |
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* can access/modify the buffer contents; drivers may |
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* perform any operations required before userspace |
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* accesses the buffer; optional. The buffer state can be |
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* one of the following: %DONE and %ERROR occur while |
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* streaming is in progress, and the %PREPARED state occurs |
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* when the queue has been canceled and all pending |
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* buffers are being returned to their default %DEQUEUED |
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* state. Typically you only have to do something if the |
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* state is %VB2_BUF_STATE_DONE, since in all other cases |
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* the buffer contents will be ignored anyway. |
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* @buf_cleanup: called once before the buffer is freed; drivers may |
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* perform any additional cleanup; optional. |
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* @start_streaming: called once to enter 'streaming' state; the driver may |
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* receive buffers with @buf_queue callback |
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* before @start_streaming is called; the driver gets the |
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* number of already queued buffers in count parameter; |
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* driver can return an error if hardware fails, in that |
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* case all buffers that have been already given by |
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* the @buf_queue callback are to be returned by the driver |
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* by calling vb2_buffer_done() with %VB2_BUF_STATE_QUEUED. |
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* If you need a minimum number of buffers before you can |
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* start streaming, then set |
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* &vb2_queue->min_buffers_needed. If that is non-zero |
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* then @start_streaming won't be called until at least |
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* that many buffers have been queued up by userspace. |
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* @stop_streaming: called when 'streaming' state must be disabled; driver |
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* should stop any DMA transactions or wait until they |
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* finish and give back all buffers it got from &buf_queue |
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* callback by calling vb2_buffer_done() with either |
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* %VB2_BUF_STATE_DONE or %VB2_BUF_STATE_ERROR; may use |
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* vb2_wait_for_all_buffers() function |
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* @buf_queue: passes buffer vb to the driver; driver may start |
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* hardware operation on this buffer; driver should give |
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* the buffer back by calling vb2_buffer_done() function; |
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* it is always called after calling VIDIOC_STREAMON() |
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* ioctl; might be called before @start_streaming callback |
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* if user pre-queued buffers before calling |
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* VIDIOC_STREAMON(). |
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* @buf_request_complete: a buffer that was never queued to the driver but is |
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* associated with a queued request was canceled. |
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* The driver will have to mark associated objects in the |
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* request as completed; required if requests are |
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* supported. |
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*/ |
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struct vb2_ops { |
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int (*queue_setup)(struct vb2_queue *q, |
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unsigned int *num_buffers, unsigned int *num_planes, |
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unsigned int sizes[], struct device *alloc_devs[]); |
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|
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void (*wait_prepare)(struct vb2_queue *q); |
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void (*wait_finish)(struct vb2_queue *q); |
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int (*buf_out_validate)(struct vb2_buffer *vb); |
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int (*buf_init)(struct vb2_buffer *vb); |
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int (*buf_prepare)(struct vb2_buffer *vb); |
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void (*buf_finish)(struct vb2_buffer *vb); |
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void (*buf_cleanup)(struct vb2_buffer *vb); |
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int (*start_streaming)(struct vb2_queue *q, unsigned int count); |
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void (*stop_streaming)(struct vb2_queue *q); |
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void (*buf_queue)(struct vb2_buffer *vb); |
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void (*buf_request_complete)(struct vb2_buffer *vb); |
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}; |
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|
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/** |
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* struct vb2_buf_ops - driver-specific callbacks. |
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* |
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* @verify_planes_array: Verify that a given user space structure contains |
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* enough planes for the buffer. This is called |
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* for each dequeued buffer. |
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* @init_buffer: given a &vb2_buffer initialize the extra data after |
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* struct vb2_buffer. |
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* For V4L2 this is a &struct vb2_v4l2_buffer. |
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* @fill_user_buffer: given a &vb2_buffer fill in the userspace structure. |
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* For V4L2 this is a &struct v4l2_buffer. |
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* @fill_vb2_buffer: given a userspace structure, fill in the &vb2_buffer. |
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* If the userspace structure is invalid, then this op |
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* will return an error. |
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* @copy_timestamp: copy the timestamp from a userspace structure to |
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* the &struct vb2_buffer. |
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*/ |
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struct vb2_buf_ops { |
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int (*verify_planes_array)(struct vb2_buffer *vb, const void *pb); |
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void (*init_buffer)(struct vb2_buffer *vb); |
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void (*fill_user_buffer)(struct vb2_buffer *vb, void *pb); |
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int (*fill_vb2_buffer)(struct vb2_buffer *vb, struct vb2_plane *planes); |
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void (*copy_timestamp)(struct vb2_buffer *vb, const void *pb); |
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}; |
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|
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/** |
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* struct vb2_queue - a videobuf queue. |
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* |
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* @type: private buffer type whose content is defined by the vb2-core |
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* caller. For example, for V4L2, it should match |
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* the types defined on &enum v4l2_buf_type. |
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* @io_modes: supported io methods (see &enum vb2_io_modes). |
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* @alloc_devs: &struct device memory type/allocator-specific per-plane device |
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* @dev: device to use for the default allocation context if the driver |
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* doesn't fill in the @alloc_devs array. |
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* @dma_attrs: DMA attributes to use for the DMA. |
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* @bidirectional: when this flag is set the DMA direction for the buffers of |
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* this queue will be overridden with %DMA_BIDIRECTIONAL direction. |
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* This is useful in cases where the hardware (firmware) writes to |
|
* a buffer which is mapped as read (%DMA_TO_DEVICE), or reads from |
|
* buffer which is mapped for write (%DMA_FROM_DEVICE) in order |
|
* to satisfy some internal hardware restrictions or adds a padding |
|
* needed by the processing algorithm. In case the DMA mapping is |
|
* not bidirectional but the hardware (firmware) trying to access |
|
* the buffer (in the opposite direction) this could lead to an |
|
* IOMMU protection faults. |
|
* @fileio_read_once: report EOF after reading the first buffer |
|
* @fileio_write_immediately: queue buffer after each write() call |
|
* @allow_zero_bytesused: allow bytesused == 0 to be passed to the driver |
|
* @quirk_poll_must_check_waiting_for_buffers: Return %EPOLLERR at poll when QBUF |
|
* has not been called. This is a vb1 idiom that has been adopted |
|
* also by vb2. |
|
* @supports_requests: this queue supports the Request API. |
|
* @requires_requests: this queue requires the Request API. If this is set to 1, |
|
* then supports_requests must be set to 1 as well. |
|
* @uses_qbuf: qbuf was used directly for this queue. Set to 1 the first |
|
* time this is called. Set to 0 when the queue is canceled. |
|
* If this is 1, then you cannot queue buffers from a request. |
|
* @uses_requests: requests are used for this queue. Set to 1 the first time |
|
* a request is queued. Set to 0 when the queue is canceled. |
|
* If this is 1, then you cannot queue buffers directly. |
|
* @allow_cache_hints: when set user-space can pass cache management hints in |
|
* order to skip cache flush/invalidation on ->prepare() or/and |
|
* ->finish(). |
|
* @lock: pointer to a mutex that protects the &struct vb2_queue. The |
|
* driver can set this to a mutex to let the v4l2 core serialize |
|
* the queuing ioctls. If the driver wants to handle locking |
|
* itself, then this should be set to NULL. This lock is not used |
|
* by the videobuf2 core API. |
|
* @owner: The filehandle that 'owns' the buffers, i.e. the filehandle |
|
* that called reqbufs, create_buffers or started fileio. |
|
* This field is not used by the videobuf2 core API, but it allows |
|
* drivers to easily associate an owner filehandle with the queue. |
|
* @ops: driver-specific callbacks |
|
* @mem_ops: memory allocator specific callbacks |
|
* @buf_ops: callbacks to deliver buffer information. |
|
* between user-space and kernel-space. |
|
* @drv_priv: driver private data. |
|
* @subsystem_flags: Flags specific to the subsystem (V4L2/DVB/etc.). Not used |
|
* by the vb2 core. |
|
* @buf_struct_size: size of the driver-specific buffer structure; |
|
* "0" indicates the driver doesn't want to use a custom buffer |
|
* structure type. In that case a subsystem-specific struct |
|
* will be used (in the case of V4L2 that is |
|
* ``sizeof(struct vb2_v4l2_buffer)``). The first field of the |
|
* driver-specific buffer structure must be the subsystem-specific |
|
* struct (vb2_v4l2_buffer in the case of V4L2). |
|
* @timestamp_flags: Timestamp flags; ``V4L2_BUF_FLAG_TIMESTAMP_*`` and |
|
* ``V4L2_BUF_FLAG_TSTAMP_SRC_*`` |
|
* @gfp_flags: additional gfp flags used when allocating the buffers. |
|
* Typically this is 0, but it may be e.g. %GFP_DMA or %__GFP_DMA32 |
|
* to force the buffer allocation to a specific memory zone. |
|
* @min_buffers_needed: the minimum number of buffers needed before |
|
* @start_streaming can be called. Used when a DMA engine |
|
* cannot be started unless at least this number of buffers |
|
* have been queued into the driver. |
|
*/ |
|
/* |
|
* Private elements (won't appear at the uAPI book): |
|
* @mmap_lock: private mutex used when buffers are allocated/freed/mmapped |
|
* @memory: current memory type used |
|
* @dma_dir: DMA mapping direction. |
|
* @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 queued and ready for streaming. |
|
* @owned_by_drv_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 |
|
* @streaming: current streaming state |
|
* @start_streaming_called: @start_streaming was called successfully and we |
|
* started streaming. |
|
* @error: a fatal error occurred on the queue |
|
* @waiting_for_buffers: used in poll() to check if vb2 is still waiting for |
|
* buffers. Only set for capture queues if qbuf has not yet been |
|
* called since poll() needs to return %EPOLLERR in that situation. |
|
* @is_multiplanar: set if buffer type is multiplanar |
|
* @is_output: set if buffer type is output |
|
* @copy_timestamp: set if vb2-core should set timestamps |
|
* @last_buffer_dequeued: used in poll() and DQBUF to immediately return if the |
|
* last decoded buffer was already dequeued. Set for capture queues |
|
* when a buffer with the %V4L2_BUF_FLAG_LAST is dequeued. |
|
* @fileio: file io emulator internal data, used only if emulator is active |
|
* @threadio: thread io internal data, used only if thread is active |
|
* @name: queue name, used for logging purpose. Initialized automatically |
|
* if left empty by drivers. |
|
*/ |
|
struct vb2_queue { |
|
unsigned int type; |
|
unsigned int io_modes; |
|
struct device *dev; |
|
unsigned long dma_attrs; |
|
unsigned int bidirectional:1; |
|
unsigned int fileio_read_once:1; |
|
unsigned int fileio_write_immediately:1; |
|
unsigned int allow_zero_bytesused:1; |
|
unsigned int quirk_poll_must_check_waiting_for_buffers:1; |
|
unsigned int supports_requests:1; |
|
unsigned int requires_requests:1; |
|
unsigned int uses_qbuf:1; |
|
unsigned int uses_requests:1; |
|
unsigned int allow_cache_hints:1; |
|
|
|
struct mutex *lock; |
|
void *owner; |
|
|
|
const struct vb2_ops *ops; |
|
const struct vb2_mem_ops *mem_ops; |
|
const struct vb2_buf_ops *buf_ops; |
|
|
|
void *drv_priv; |
|
u32 subsystem_flags; |
|
unsigned int buf_struct_size; |
|
u32 timestamp_flags; |
|
gfp_t gfp_flags; |
|
u32 min_buffers_needed; |
|
|
|
struct device *alloc_devs[VB2_MAX_PLANES]; |
|
|
|
/* private: internal use only */ |
|
struct mutex mmap_lock; |
|
unsigned int memory; |
|
enum dma_data_direction dma_dir; |
|
struct vb2_buffer *bufs[VB2_MAX_FRAME]; |
|
unsigned int num_buffers; |
|
|
|
struct list_head queued_list; |
|
unsigned int queued_count; |
|
|
|
atomic_t owned_by_drv_count; |
|
struct list_head done_list; |
|
spinlock_t done_lock; |
|
wait_queue_head_t done_wq; |
|
|
|
unsigned int streaming:1; |
|
unsigned int start_streaming_called:1; |
|
unsigned int error:1; |
|
unsigned int waiting_for_buffers:1; |
|
unsigned int waiting_in_dqbuf:1; |
|
unsigned int is_multiplanar:1; |
|
unsigned int is_output:1; |
|
unsigned int copy_timestamp:1; |
|
unsigned int last_buffer_dequeued:1; |
|
|
|
struct vb2_fileio_data *fileio; |
|
struct vb2_threadio_data *threadio; |
|
|
|
char name[32]; |
|
|
|
#ifdef CONFIG_VIDEO_ADV_DEBUG |
|
/* |
|
* Counters for how often these queue-related ops are |
|
* called. Used to check for unbalanced ops. |
|
*/ |
|
u32 cnt_queue_setup; |
|
u32 cnt_wait_prepare; |
|
u32 cnt_wait_finish; |
|
u32 cnt_start_streaming; |
|
u32 cnt_stop_streaming; |
|
#endif |
|
}; |
|
|
|
/** |
|
* vb2_queue_allows_cache_hints() - Return true if the queue allows cache |
|
* and memory consistency hints. |
|
* |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue |
|
*/ |
|
static inline bool vb2_queue_allows_cache_hints(struct vb2_queue *q) |
|
{ |
|
return q->allow_cache_hints && q->memory == VB2_MEMORY_MMAP; |
|
} |
|
|
|
/** |
|
* vb2_plane_vaddr() - Return a kernel virtual address of a given plane. |
|
* @vb: pointer to &struct vb2_buffer to which the plane in |
|
* question belongs to. |
|
* @plane_no: plane number for which the address is to be returned. |
|
* |
|
* This function returns a kernel virtual address of a given plane if |
|
* such a mapping exist, NULL otherwise. |
|
*/ |
|
void *vb2_plane_vaddr(struct vb2_buffer *vb, unsigned int plane_no); |
|
|
|
/** |
|
* vb2_plane_cookie() - Return allocator specific cookie for the given plane. |
|
* @vb: pointer to &struct vb2_buffer to which the plane in |
|
* question belongs to. |
|
* @plane_no: plane number for which the cookie is to be returned. |
|
* |
|
* This function returns an allocator specific cookie for a given plane if |
|
* available, NULL otherwise. The allocator should provide some simple static |
|
* inline function, which would convert this cookie to the allocator specific |
|
* type that can be used directly by the driver to access the buffer. This can |
|
* be for example physical address, pointer to scatter list or IOMMU mapping. |
|
*/ |
|
void *vb2_plane_cookie(struct vb2_buffer *vb, unsigned int plane_no); |
|
|
|
/** |
|
* vb2_buffer_done() - inform videobuf that an operation on a buffer |
|
* is finished. |
|
* @vb: pointer to &struct vb2_buffer to be used. |
|
* @state: state of the buffer, as defined by &enum vb2_buffer_state. |
|
* Either %VB2_BUF_STATE_DONE if the operation finished |
|
* successfully, %VB2_BUF_STATE_ERROR if the operation finished |
|
* with an error or %VB2_BUF_STATE_QUEUED. |
|
* |
|
* This function should be called by the driver after a hardware operation on |
|
* a buffer is finished and the buffer may be returned to userspace. The driver |
|
* cannot use this buffer anymore until it is queued back to it by videobuf |
|
* by the means of &vb2_ops->buf_queue callback. Only buffers previously queued |
|
* to the driver by &vb2_ops->buf_queue can be passed to this function. |
|
* |
|
* While streaming a buffer can only be returned in state DONE or ERROR. |
|
* The &vb2_ops->start_streaming op can also return them in case the DMA engine |
|
* cannot be started for some reason. In that case the buffers should be |
|
* returned with state QUEUED to put them back into the queue. |
|
*/ |
|
void vb2_buffer_done(struct vb2_buffer *vb, enum vb2_buffer_state state); |
|
|
|
/** |
|
* vb2_discard_done() - discard all buffers marked as DONE. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* |
|
* This function is intended to be used with suspend/resume operations. It |
|
* discards all 'done' buffers as they would be too old to be requested after |
|
* resume. |
|
* |
|
* Drivers must stop the hardware and synchronize with interrupt handlers and/or |
|
* delayed works before calling this function to make sure no buffer will be |
|
* touched by the driver and/or hardware. |
|
*/ |
|
void vb2_discard_done(struct vb2_queue *q); |
|
|
|
/** |
|
* vb2_wait_for_all_buffers() - wait until all buffers are given back to vb2. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* |
|
* This function will wait until all buffers that have been given to the driver |
|
* by &vb2_ops->buf_queue are given back to vb2 with vb2_buffer_done(). It |
|
* doesn't call &vb2_ops->wait_prepare/&vb2_ops->wait_finish pair. |
|
* It is intended to be called with all locks taken, for example from |
|
* &vb2_ops->stop_streaming callback. |
|
*/ |
|
int vb2_wait_for_all_buffers(struct vb2_queue *q); |
|
|
|
/** |
|
* vb2_core_querybuf() - query video buffer information. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* @index: id number of the buffer. |
|
* @pb: buffer struct passed from userspace. |
|
* |
|
* Videobuf2 core helper to implement VIDIOC_QUERYBUF() operation. It is called |
|
* internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. |
|
* |
|
* The passed buffer should have been verified. |
|
* |
|
* This function fills the relevant information for the userspace. |
|
* |
|
* Return: returns zero on success; an error code otherwise. |
|
*/ |
|
void vb2_core_querybuf(struct vb2_queue *q, unsigned int index, void *pb); |
|
|
|
/** |
|
* vb2_core_reqbufs() - Initiate streaming. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* @memory: memory type, as defined by &enum vb2_memory. |
|
* @count: requested buffer count. |
|
* |
|
* Videobuf2 core helper to implement VIDIOC_REQBUF() operation. It is called |
|
* internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. |
|
* |
|
* This function: |
|
* |
|
* #) verifies streaming parameters passed from the userspace; |
|
* #) sets up the queue; |
|
* #) negotiates number of buffers and planes per buffer with the driver |
|
* to be used during streaming; |
|
* #) allocates internal buffer structures (&struct vb2_buffer), according to |
|
* the agreed parameters; |
|
* #) for MMAP memory type, allocates actual video memory, using the |
|
* memory handling/allocation routines provided during queue initialization. |
|
* |
|
* If req->count is 0, all the memory will be freed instead. |
|
* |
|
* If the queue has been allocated previously by a previous vb2_core_reqbufs() |
|
* call and the queue is not busy, memory will be reallocated. |
|
* |
|
* Return: returns zero on success; an error code otherwise. |
|
*/ |
|
int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, |
|
unsigned int *count); |
|
|
|
/** |
|
* vb2_core_create_bufs() - Allocate buffers and any required auxiliary structs |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* @memory: memory type, as defined by &enum vb2_memory. |
|
* @count: requested buffer count. |
|
* @requested_planes: number of planes requested. |
|
* @requested_sizes: array with the size of the planes. |
|
* |
|
* Videobuf2 core helper to implement VIDIOC_CREATE_BUFS() operation. It is |
|
* called internally by VB2 by an API-specific handler, like |
|
* ``videobuf2-v4l2.h``. |
|
* |
|
* This function: |
|
* |
|
* #) verifies parameter sanity; |
|
* #) calls the &vb2_ops->queue_setup queue operation; |
|
* #) performs any necessary memory allocations. |
|
* |
|
* Return: returns zero on success; an error code otherwise. |
|
*/ |
|
int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, |
|
unsigned int *count, |
|
unsigned int requested_planes, |
|
const unsigned int requested_sizes[]); |
|
|
|
/** |
|
* vb2_core_prepare_buf() - Pass ownership of a buffer from userspace |
|
* to the kernel. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* @index: id number of the buffer. |
|
* @pb: buffer structure passed from userspace to |
|
* &v4l2_ioctl_ops->vidioc_prepare_buf handler in driver. |
|
* |
|
* Videobuf2 core helper to implement VIDIOC_PREPARE_BUF() operation. It is |
|
* called internally by VB2 by an API-specific handler, like |
|
* ``videobuf2-v4l2.h``. |
|
* |
|
* The passed buffer should have been verified. |
|
* |
|
* This function calls vb2_ops->buf_prepare callback in the driver |
|
* (if provided), in which driver-specific buffer initialization can |
|
* be performed. |
|
* |
|
* Return: returns zero on success; an error code otherwise. |
|
*/ |
|
int vb2_core_prepare_buf(struct vb2_queue *q, unsigned int index, void *pb); |
|
|
|
/** |
|
* vb2_core_qbuf() - Queue a buffer from userspace |
|
* |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* @index: id number of the buffer |
|
* @pb: buffer structure passed from userspace to |
|
* v4l2_ioctl_ops->vidioc_qbuf handler in driver |
|
* @req: pointer to &struct media_request, may be NULL. |
|
* |
|
* Videobuf2 core helper to implement VIDIOC_QBUF() operation. It is called |
|
* internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. |
|
* |
|
* This function: |
|
* |
|
* #) If @req is non-NULL, then the buffer will be bound to this |
|
* media request and it returns. The buffer will be prepared and |
|
* queued to the driver (i.e. the next two steps) when the request |
|
* itself is queued. |
|
* #) 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. |
|
* |
|
* Return: returns zero on success; an error code otherwise. |
|
*/ |
|
int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb, |
|
struct media_request *req); |
|
|
|
/** |
|
* vb2_core_dqbuf() - Dequeue a buffer to the userspace |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue |
|
* @pindex: pointer to the buffer index. May be NULL |
|
* @pb: 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. |
|
* |
|
* Videobuf2 core helper to implement VIDIOC_DQBUF() operation. It is called |
|
* internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. |
|
* |
|
* This function: |
|
* |
|
* #) 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, |
|
* #) the buffer struct members are filled with relevant information for |
|
* the userspace. |
|
* |
|
* Return: returns zero on success; an error code otherwise. |
|
*/ |
|
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. |
|
* |
|
* Videobuf2 core helper to implement VIDIOC_STREAMON() operation. It is called |
|
* internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. |
|
* |
|
* Return: returns zero on success; an error code otherwise. |
|
*/ |
|
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. |
|
* |
|
* Videobuf2 core helper to implement VIDIOC_STREAMOFF() operation. It is |
|
* called internally by VB2 by an API-specific handler, like |
|
* ``videobuf2-v4l2.h``. |
|
* |
|
* Return: returns zero on success; an error code otherwise. |
|
*/ |
|
int vb2_core_streamoff(struct vb2_queue *q, unsigned int type); |
|
|
|
/** |
|
* vb2_core_expbuf_dmabuf() - Export a buffer as a dma_buf structure |
|
* @q: videobuf2 queue |
|
* @type: buffer type |
|
* @index: id number of the buffer |
|
* @plane: index of the plane to be exported, 0 for single plane queues |
|
* @flags: flags for newly created file, currently only O_CLOEXEC is |
|
* supported, refer to manual of open syscall for more details |
|
* @dmabuf: Returns the dmabuf pointer |
|
* |
|
*/ |
|
int vb2_core_expbuf_dmabuf(struct vb2_queue *q, unsigned int type, |
|
unsigned int index, unsigned int plane, |
|
unsigned int flags, struct dma_buf **dmabuf); |
|
|
|
/** |
|
* vb2_core_expbuf() - Export a buffer as a file descriptor. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* @fd: pointer to the file descriptor associated with DMABUF |
|
* (set by driver). |
|
* @type: buffer type. |
|
* @index: id number of the buffer. |
|
* @plane: index of the plane to be exported, 0 for single plane queues |
|
* @flags: file flags for newly created file, as defined at |
|
* include/uapi/asm-generic/fcntl.h. |
|
* Currently, the only used flag is %O_CLOEXEC. |
|
* is supported, refer to manual of open syscall for more details. |
|
* |
|
* |
|
* Videobuf2 core helper to implement VIDIOC_EXPBUF() operation. It is called |
|
* internally by VB2 by an API-specific handler, like ``videobuf2-v4l2.h``. |
|
* |
|
* Return: returns zero on success; an error code otherwise. |
|
*/ |
|
int vb2_core_expbuf(struct vb2_queue *q, int *fd, unsigned int type, |
|
unsigned int index, unsigned int plane, unsigned int flags); |
|
|
|
/** |
|
* vb2_core_queue_init() - initialize a videobuf2 queue |
|
* @q: pointer to &struct vb2_queue with 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. |
|
* |
|
* .. note:: |
|
* |
|
* The following fields at @q should be set before calling this function: |
|
* &vb2_queue->ops, &vb2_queue->mem_ops, &vb2_queue->type. |
|
*/ |
|
int vb2_core_queue_init(struct vb2_queue *q); |
|
|
|
/** |
|
* vb2_core_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 &struct vb2_queue itself. |
|
*/ |
|
void vb2_core_queue_release(struct vb2_queue *q); |
|
|
|
/** |
|
* vb2_queue_error() - signal a fatal error on the queue |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* |
|
* Flag that a fatal unrecoverable error has occurred and wake up all processes |
|
* waiting on the queue. Polling will now set %EPOLLERR and queuing and dequeuing |
|
* buffers will return %-EIO. |
|
* |
|
* The error flag will be cleared when canceling the queue, either from |
|
* vb2_streamoff() or vb2_queue_release(). Drivers should thus not call this |
|
* function before starting the stream, otherwise the error flag will remain set |
|
* until the queue is released when closing the device node. |
|
*/ |
|
void vb2_queue_error(struct vb2_queue *q); |
|
|
|
/** |
|
* vb2_mmap() - map video buffers into application address space. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* @vma: pointer to &struct vm_area_struct with the vma passed |
|
* to the mmap file operation handler in the driver. |
|
* |
|
* Should be called from mmap file operation handler of a driver. |
|
* This function maps one plane of one of the available video buffers to |
|
* userspace. To map whole video memory allocated on reqbufs, this function |
|
* has to be called once per each plane per each buffer previously allocated. |
|
* |
|
* When the userspace application calls mmap, it passes to it an offset returned |
|
* to it earlier by the means of &v4l2_ioctl_ops->vidioc_querybuf handler. |
|
* That offset acts as a "cookie", which is then used to identify the plane |
|
* to be mapped. |
|
* |
|
* This function finds a plane with a matching offset and a mapping is performed |
|
* by the means of a provided memory operation. |
|
* |
|
* The return values from this function are intended to be directly returned |
|
* from the mmap handler in driver. |
|
*/ |
|
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, |
|
unsigned long pgoff, |
|
unsigned long flags); |
|
#endif |
|
|
|
/** |
|
* 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. |
|
* @wait: &poll_table 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. |
|
* |
|
* The return values from this function are intended to be directly returned |
|
* from poll handler in driver. |
|
*/ |
|
__poll_t 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_write() - 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); |
|
|
|
/** |
|
* typedef vb2_thread_fnc - callback function for use with vb2_thread. |
|
* |
|
* @vb: pointer to struct &vb2_buffer. |
|
* @priv: pointer to a private data. |
|
* |
|
* This is called whenever a buffer is dequeued in the thread. |
|
*/ |
|
typedef int (*vb2_thread_fnc)(struct vb2_buffer *vb, void *priv); |
|
|
|
/** |
|
* vb2_thread_start() - start a thread for the given queue. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* @fnc: &vb2_thread_fnc callback function. |
|
* @priv: priv pointer passed to the callback function. |
|
* @thread_name:the name of the thread. This will be prefixed with "vb2-". |
|
* |
|
* This starts a thread that will queue and dequeue until an error occurs |
|
* or vb2_thread_stop() is called. |
|
* |
|
* .. attention:: |
|
* |
|
* This function should not be used for anything else but the videobuf2-dvb |
|
* support. If you think you have another good use-case for this, then please |
|
* contact the linux-media mailing list first. |
|
*/ |
|
int vb2_thread_start(struct vb2_queue *q, vb2_thread_fnc fnc, void *priv, |
|
const char *thread_name); |
|
|
|
/** |
|
* vb2_thread_stop() - stop the thread for the given queue. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
*/ |
|
int vb2_thread_stop(struct vb2_queue *q); |
|
|
|
/** |
|
* vb2_is_streaming() - return streaming status of the queue. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
*/ |
|
static inline bool vb2_is_streaming(struct vb2_queue *q) |
|
{ |
|
return q->streaming; |
|
} |
|
|
|
/** |
|
* vb2_fileio_is_active() - return true if fileio is active. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* |
|
* This returns true if read() or write() is used to stream the data |
|
* as opposed to stream I/O. This is almost never an important distinction, |
|
* except in rare cases. One such case is that using read() or write() to |
|
* stream a format using %V4L2_FIELD_ALTERNATE is not allowed since there |
|
* is no way you can pass the field information of each buffer to/from |
|
* userspace. A driver that supports this field format should check for |
|
* this in the &vb2_ops->queue_setup op and reject it if this function returns |
|
* true. |
|
*/ |
|
static inline bool vb2_fileio_is_active(struct vb2_queue *q) |
|
{ |
|
return q->fileio; |
|
} |
|
|
|
/** |
|
* vb2_is_busy() - return busy status of the queue. |
|
* @q: pointer to &struct vb2_queue with videobuf2 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: pointer to &struct vb2_queue with videobuf2 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: pointer to &struct vb2_buffer to which the plane in |
|
* question belongs to. |
|
* @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->planes[plane_no].bytesused = size; |
|
} |
|
|
|
/** |
|
* vb2_get_plane_payload() - get bytesused for the plane plane_no |
|
* @vb: pointer to &struct vb2_buffer to which the plane in |
|
* question belongs to. |
|
* @plane_no: plane number for which payload should be set. |
|
*/ |
|
static inline unsigned long vb2_get_plane_payload(struct vb2_buffer *vb, |
|
unsigned int plane_no) |
|
{ |
|
if (plane_no < vb->num_planes) |
|
return vb->planes[plane_no].bytesused; |
|
return 0; |
|
} |
|
|
|
/** |
|
* vb2_plane_size() - return plane size in bytes. |
|
* @vb: pointer to &struct vb2_buffer to which the plane in |
|
* question belongs to. |
|
* @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->planes[plane_no].length; |
|
return 0; |
|
} |
|
|
|
/** |
|
* vb2_start_streaming_called() - return streaming status of driver. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
*/ |
|
static inline bool vb2_start_streaming_called(struct vb2_queue *q) |
|
{ |
|
return q->start_streaming_called; |
|
} |
|
|
|
/** |
|
* vb2_clear_last_buffer_dequeued() - clear last buffer dequeued flag of queue. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
*/ |
|
static inline void vb2_clear_last_buffer_dequeued(struct vb2_queue *q) |
|
{ |
|
q->last_buffer_dequeued = false; |
|
} |
|
|
|
/** |
|
* vb2_get_buffer() - get a buffer from a queue |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* @index: buffer index |
|
* |
|
* This function obtains a buffer from a queue, by its index. |
|
* Keep in mind that there is no refcounting involved in this |
|
* operation, so the buffer lifetime should be taken into |
|
* consideration. |
|
*/ |
|
static inline struct vb2_buffer *vb2_get_buffer(struct vb2_queue *q, |
|
unsigned int index) |
|
{ |
|
if (index < q->num_buffers) |
|
return q->bufs[index]; |
|
return NULL; |
|
} |
|
|
|
/* |
|
* The following functions are not part of the vb2 core API, but are useful |
|
* functions for videobuf2-*. |
|
*/ |
|
|
|
/** |
|
* vb2_buffer_in_use() - return true if the buffer is in use and |
|
* the queue cannot be freed (by the means of VIDIOC_REQBUFS(0)) call. |
|
* |
|
* @vb: buffer for which plane size should be returned. |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
*/ |
|
bool vb2_buffer_in_use(struct vb2_queue *q, struct vb2_buffer *vb); |
|
|
|
/** |
|
* vb2_verify_memory_type() - Check whether the memory type and buffer type |
|
* passed to a buffer operation are compatible with the queue. |
|
* |
|
* @q: pointer to &struct vb2_queue with videobuf2 queue. |
|
* @memory: memory model, as defined by enum &vb2_memory. |
|
* @type: private buffer type whose content is defined by the vb2-core |
|
* caller. For example, for V4L2, it should match |
|
* the types defined on enum &v4l2_buf_type. |
|
*/ |
|
int vb2_verify_memory_type(struct vb2_queue *q, |
|
enum vb2_memory memory, unsigned int type); |
|
|
|
/** |
|
* vb2_request_object_is_buffer() - return true if the object is a buffer |
|
* |
|
* @obj: the request object. |
|
*/ |
|
bool vb2_request_object_is_buffer(struct media_request_object *obj); |
|
|
|
/** |
|
* vb2_request_buffer_cnt() - return the number of buffers in the request |
|
* |
|
* @req: the request. |
|
*/ |
|
unsigned int vb2_request_buffer_cnt(struct media_request *req); |
|
|
|
#endif /* _MEDIA_VIDEOBUF2_CORE_H */
|
|
|