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-rw-r--r--include/media/videobuf-dma-sg.h142
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diff --git a/include/media/videobuf-dma-sg.h b/include/media/videobuf-dma-sg.h
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+/*
+ * 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_mapping *map;
+ struct videobuf_dmabuf dma;
+};
+
+/* FIXME: To be removed soon */
+typedef int (vb_map_sg_t)(void *dev, struct scatterlist *sglist, int nr_pages,
+ int direction);
+
+/* FIXME: To be removed soon */
+struct videobuf_dma_sg_ops
+{
+ vb_map_sg_t *vb_map_sg;
+ vb_map_sg_t *vb_dma_sync_sg;
+ vb_map_sg_t *vb_unmap_sg;
+
+};
+
+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);
+
+/* FIXME: temporary routine for vivi and tm6000, while lacking implementation
+ * of videobuf-vmalloc
+ */
+void videobuf_set_pci_ops (struct videobuf_queue* q,
+ struct videobuf_dma_sg_ops *ops);
+

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