^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) /* SPDX-License-Identifier: GPL-2.0-only */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * helper functions for SG DMA video4linux capture buffers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * The functions expect the hardware being able to scatter gather
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * (i.e. the buffers are not linear in physical memory, but fragmented
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * into PAGE_SIZE chunks). They also assume the driver does not need
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * to touch the video data.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * (c) 2007 Mauro Carvalho Chehab, <mchehab@kernel.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) * Highly based on video-buf written originally by:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) * (c) 2001,02 Gerd Knorr <kraxel@bytesex.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) * (c) 2006 Mauro Carvalho Chehab, <mchehab@kernel.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) * (c) 2006 Ted Walther and John Sokol
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #ifndef _VIDEOBUF_DMA_SG_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #define _VIDEOBUF_DMA_SG_H
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <media/videobuf-core.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) /* --------------------------------------------------------------------- */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) * A small set of helper functions to manage buffers (both userland
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) * and kernel) for DMA.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) * videobuf_dma_init_*()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) * creates a buffer. The userland version takes a userspace
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * pointer + length. The kernel version just wants the size and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * does memory allocation too using vmalloc_32().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) * videobuf_dma_*()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) * see Documentation/core-api/dma-api-howto.rst, these functions to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) * basically the same. The map function does also build a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) * scatterlist for the buffer (and unmap frees it ...)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) * videobuf_dma_free()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) * no comment ...
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) struct videobuf_dmabuf {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) u32 magic;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) /* for userland buffer */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) int offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) size_t size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) struct page **pages;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) /* for kernel buffers */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) void *vaddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) struct page **vaddr_pages;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) dma_addr_t *dma_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) struct device *dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) /* for overlay buffers (pci-pci dma) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) dma_addr_t bus_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) /* common */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) struct scatterlist *sglist;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) int sglen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) unsigned long nr_pages;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) int direction;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) struct videobuf_dma_sg_memory {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) u32 magic;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) /* for mmap'ed buffers */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) struct videobuf_dmabuf dma;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) * Scatter-gather DMA buffer API.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) * These functions provide a simple way to create a page list and a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) * scatter-gather list from a kernel, userspace of physical address and map the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) * memory for DMA operation.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) * Despite the name, this is totally unrelated to videobuf, except that
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) * videobuf-dma-sg uses the same API internally.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) int videobuf_dma_free(struct videobuf_dmabuf *dma);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) int videobuf_dma_unmap(struct device *dev, struct videobuf_dmabuf *dma);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) struct videobuf_dmabuf *videobuf_to_dma(struct videobuf_buffer *buf);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) void *videobuf_sg_alloc(size_t size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) void videobuf_queue_sg_init(struct videobuf_queue *q,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) const struct videobuf_queue_ops *ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) struct device *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) spinlock_t *irqlock,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) enum v4l2_buf_type type,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) enum v4l2_field field,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) unsigned int msize,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) void *priv,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) struct mutex *ext_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) #endif /* _VIDEOBUF_DMA_SG_H */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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