5ddff43435
Before the videobuf redesign, a procedure for re-using videobuf without PCI scatter/gather where provided by changing the pci-dependent operations by other operations. With the newer approach, those methods are obsolete and can safelly be removed. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
123 lines
3.8 KiB
C
123 lines
3.8 KiB
C
/*
|
|
* helper functions for PCI DMA video4linux capture buffers
|
|
*
|
|
* The functions expect the hardware being able to scatter gatter
|
|
* (i.e. the buffers are not linear in physical memory, but fragmented
|
|
* into PAGE_SIZE chunks). They also assume the driver does not need
|
|
* to touch the video data.
|
|
*
|
|
* (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org>
|
|
*
|
|
* Highly based on video-buf written originally by:
|
|
* (c) 2001,02 Gerd Knorr <kraxel@bytesex.org>
|
|
* (c) 2006 Mauro Carvalho Chehab, <mchehab@infradead.org>
|
|
* (c) 2006 Ted Walther and John Sokol
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2
|
|
*/
|
|
|
|
#include <media/videobuf-core.h>
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
/*
|
|
* Return a scatterlist for some page-aligned vmalloc()'ed memory
|
|
* block (NULL on errors). Memory for the scatterlist is allocated
|
|
* using kmalloc. The caller must free the memory.
|
|
*/
|
|
struct scatterlist* videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages);
|
|
|
|
/*
|
|
* Return a scatterlist for a an array of userpages (NULL on errors).
|
|
* Memory for the scatterlist is allocated using kmalloc. The caller
|
|
* must free the memory.
|
|
*/
|
|
struct scatterlist* videobuf_pages_to_sg(struct page **pages, int nr_pages,
|
|
int offset);
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
/*
|
|
* A small set of helper functions to manage buffers (both userland
|
|
* and kernel) for DMA.
|
|
*
|
|
* videobuf_dma_init_*()
|
|
* creates a buffer. The userland version takes a userspace
|
|
* pointer + length. The kernel version just wants the size and
|
|
* does memory allocation too using vmalloc_32().
|
|
*
|
|
* videobuf_dma_*()
|
|
* see Documentation/DMA-mapping.txt, these functions to
|
|
* basically the same. The map function does also build a
|
|
* scatterlist for the buffer (and unmap frees it ...)
|
|
*
|
|
* videobuf_dma_free()
|
|
* no comment ...
|
|
*
|
|
*/
|
|
|
|
struct videobuf_dmabuf {
|
|
u32 magic;
|
|
|
|
/* for userland buffer */
|
|
int offset;
|
|
struct page **pages;
|
|
|
|
/* for kernel buffers */
|
|
void *vmalloc;
|
|
|
|
/* Stores the userspace pointer to vmalloc area */
|
|
void *varea;
|
|
|
|
/* for overlay buffers (pci-pci dma) */
|
|
dma_addr_t bus_addr;
|
|
|
|
/* common */
|
|
struct scatterlist *sglist;
|
|
int sglen;
|
|
int nr_pages;
|
|
int direction;
|
|
};
|
|
|
|
struct videbuf_pci_sg_memory
|
|
{
|
|
u32 magic;
|
|
|
|
/* for mmap'ed buffers */
|
|
struct videobuf_dmabuf dma;
|
|
};
|
|
|
|
void videobuf_dma_init(struct videobuf_dmabuf *dma);
|
|
int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
|
|
unsigned long data, unsigned long size);
|
|
int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
|
|
int nr_pages);
|
|
int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
|
|
dma_addr_t addr, int nr_pages);
|
|
int videobuf_dma_free(struct videobuf_dmabuf *dma);
|
|
|
|
int videobuf_dma_map(struct videobuf_queue* q,struct videobuf_dmabuf *dma);
|
|
int videobuf_dma_sync(struct videobuf_queue* q,struct videobuf_dmabuf *dma);
|
|
int videobuf_dma_unmap(struct videobuf_queue* q,struct videobuf_dmabuf *dma);
|
|
struct videobuf_dmabuf *videobuf_to_dma (struct videobuf_buffer *buf);
|
|
|
|
void *videobuf_pci_alloc (size_t size);
|
|
|
|
void videobuf_queue_pci_init(struct videobuf_queue* q,
|
|
struct videobuf_queue_ops *ops,
|
|
void *dev,
|
|
spinlock_t *irqlock,
|
|
enum v4l2_buf_type type,
|
|
enum v4l2_field field,
|
|
unsigned int msize,
|
|
void *priv);
|
|
|
|
/*FIXME: these variants are used only on *-alsa code, where videobuf is
|
|
* used without queue
|
|
*/
|
|
int videobuf_pci_dma_map(struct pci_dev *pci,struct videobuf_dmabuf *dma);
|
|
int videobuf_pci_dma_unmap(struct pci_dev *pci,struct videobuf_dmabuf *dma);
|
|
|