projects / mirror_ubuntu-bionic-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 7a7d9a89 | 1 | /* |
| 0705135e | 2 | * helper functions for SG DMA video4linux capture buffers |
| 7a7d9a89 | 3 | * |
| 5d6aaf50 | 4 | * The functions expect the hardware being able to scatter gather |
| 7a7d9a89 MCC |
5 | * (i.e. the buffers are not linear in physical memory, but fragmented |
| 6 | * into PAGE_SIZE chunks). They also assume the driver does not need | |
| 7 | * to touch the video data. | |
| 8 | * | |
| 9 | * (c) 2007 Mauro Carvalho Chehab, <mchehab@infradead.org> | |
| 10 | * | |
| 11 | * Highly based on video-buf written originally by: | |
| 12 | * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org> | |
| 13 | * (c) 2006 Mauro Carvalho Chehab, <mchehab@infradead.org> | |
| 14 | * (c) 2006 Ted Walther and John Sokol | |
| 15 | * | |
| 16 | * This program is free software; you can redistribute it and/or modify | |
| 17 | * it under the terms of the GNU General Public License as published by | |
| 18 | * the Free Software Foundation; either version 2 | |
| 19 | */ | |
| 20 | ||
| 21 | #include <media/videobuf-core.h> | |
| 22 | ||
| 23 | /* --------------------------------------------------------------------- */ | |
| 24 | ||
| 25 | /* | |
| 26 | * Return a scatterlist for some page-aligned vmalloc()'ed memory | |
| 27 | * block (NULL on errors). Memory for the scatterlist is allocated | |
| 28 | * using kmalloc. The caller must free the memory. | |
| 29 | */ | |
| 30 | struct scatterlist* videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages); | |
| 31 | ||
| 32 | /* | |
| 33 | * Return a scatterlist for a an array of userpages (NULL on errors). | |
| 34 | * Memory for the scatterlist is allocated using kmalloc. The caller | |
| 35 | * must free the memory. | |
| 36 | */ | |
| 37 | struct scatterlist* videobuf_pages_to_sg(struct page **pages, int nr_pages, | |
| 38 | int offset); | |
| 39 | ||
| 40 | /* --------------------------------------------------------------------- */ | |
| 41 | ||
| 42 | /* | |
| 43 | * A small set of helper functions to manage buffers (both userland | |
| 44 | * and kernel) for DMA. | |
| 45 | * | |
| 46 | * videobuf_dma_init_*() | |
| 47 | * creates a buffer. The userland version takes a userspace | |
| 48 | * pointer + length. The kernel version just wants the size and | |
| 49 | * does memory allocation too using vmalloc_32(). | |
| 50 | * | |
| 51 | * videobuf_dma_*() | |
| 5872fb94 | 52 | * see Documentation/PCI/PCI-DMA-mapping.txt, these functions to |
| 7a7d9a89 MCC |
53 | * basically the same. The map function does also build a |
| 54 | * scatterlist for the buffer (and unmap frees it ...) | |
| 55 | * | |
| 56 | * videobuf_dma_free() | |
| 57 | * no comment ... | |
| 58 | * | |
| 59 | */ | |
| 60 | ||
| 61 | struct videobuf_dmabuf { | |
| 62 | u32 magic; | |
| 63 | ||
| 64 | /* for userland buffer */ | |
| 65 | int offset; | |
| 66 | struct page **pages; | |
| 67 | ||
| 68 | /* for kernel buffers */ | |
| 69 | void *vmalloc; | |
| 70 | ||
| 7a7d9a89 MCC |
71 | /* for overlay buffers (pci-pci dma) */ |
| 72 | dma_addr_t bus_addr; | |
| 73 | ||
| 74 | /* common */ | |
| 75 | struct scatterlist *sglist; | |
| 76 | int sglen; | |
| 77 | int nr_pages; | |
| 78 | int direction; | |
| 79 | }; | |
| 80 | ||
| 0705135e | 81 | struct videobuf_dma_sg_memory |
| 7a7d9a89 MCC |
82 | { |
| 83 | u32 magic; | |
| 84 | ||
| 85 | /* for mmap'ed buffers */ | |
| 7a7d9a89 MCC |
86 | struct videobuf_dmabuf dma; |
| 87 | }; | |
| 88 | ||
| 7a7d9a89 MCC |
89 | void videobuf_dma_init(struct videobuf_dmabuf *dma); |
| 90 | int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction, | |
| 91 | unsigned long data, unsigned long size); | |
| 92 | int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction, | |
| 93 | int nr_pages); | |
| 94 | int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction, | |
| 95 | dma_addr_t addr, int nr_pages); | |
| 96 | int videobuf_dma_free(struct videobuf_dmabuf *dma); | |
| 97 | ||
| 98 | int videobuf_dma_map(struct videobuf_queue* q,struct videobuf_dmabuf *dma); | |
| 99 | int videobuf_dma_sync(struct videobuf_queue* q,struct videobuf_dmabuf *dma); | |
| 100 | int videobuf_dma_unmap(struct videobuf_queue* q,struct videobuf_dmabuf *dma); | |
| 101 | struct videobuf_dmabuf *videobuf_to_dma (struct videobuf_buffer *buf); | |
| 102 | ||
| 0705135e | 103 | void *videobuf_sg_alloc(size_t size); |
| 7a7d9a89 | 104 | |
| 0705135e | 105 | void videobuf_queue_sg_init(struct videobuf_queue* q, |
| 38a54f35 | 106 | const struct videobuf_queue_ops *ops, |
| 0705135e | 107 | struct device *dev, |
| 7a7d9a89 MCC |
108 | spinlock_t *irqlock, |
| 109 | enum v4l2_buf_type type, | |
| 110 | enum v4l2_field field, | |
| 111 | unsigned int msize, | |
| 112 | void *priv); | |
| 113 | ||
| 114 | /*FIXME: these variants are used only on *-alsa code, where videobuf is | |
| 115 | * used without queue | |
| 116 | */ | |
| 0705135e GL |
117 | int videobuf_sg_dma_map(struct device *dev, struct videobuf_dmabuf *dma); |
| 118 | int videobuf_sg_dma_unmap(struct device *dev, struct videobuf_dmabuf *dma); | |
| 7a7d9a89 | 119 |