V4L/DVB (3516): Make video_buf more generic
Video_buf were concerned to allow PCI devices to be used as
video capture devices. This patch extends video_buf features
by virtualizing pci-dependent functions and allowing other
type of devices to use it.
It is still DMA centric, although it may be used also by
devices that emulates scatter/gather behavior or a DMA device
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/include/media/video-buf.h b/include/media/video-buf.h
index d90dec5..fff3fd0 100644
--- a/include/media/video-buf.h
+++ b/include/media/video-buf.h
@@ -1,15 +1,20 @@
/*
*
* generic helper functions for video4linux capture buffers, to handle
- * memory management and PCI DMA. Right now bttv + saa7134 use it.
+ * memory management and PCI DMA.
+ * Right now, bttv, saa7134, saa7146 and cx88 use it.
*
* 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 (thus it is probably not useful for USB as
- * data often must be uncompressed by the drivers).
+ * to touch the video data.
+ *
+ * device specific map/unmap/sync stuff now are mapped as file operations
+ * to allow its usage by USB and virtual devices.
*
* (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
@@ -38,6 +43,9 @@
struct scatterlist* videobuf_pages_to_sg(struct page **pages, int nr_pages,
int offset);
+struct videobuf_buffer;
+struct videobuf_queue;
+
/* --------------------------------------------------------------------- */
/*
@@ -49,7 +57,7 @@
* pointer + length. The kernel version just wants the size and
* does memory allocation too using vmalloc_32().
*
- * videobuf_dma_pci_*()
+ * 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 ...)
@@ -86,12 +94,18 @@
int nr_pages);
int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
dma_addr_t addr, int nr_pages);
-int videobuf_dma_pci_map(struct pci_dev *dev, struct videobuf_dmabuf *dma);
-int videobuf_dma_pci_sync(struct pci_dev *dev,
- struct videobuf_dmabuf *dma);
-int videobuf_dma_pci_unmap(struct pci_dev *dev, struct videobuf_dmabuf *dma);
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);
+
+ /*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);
+
/* --------------------------------------------------------------------- */
/*
@@ -115,9 +129,6 @@
*
*/
-struct videobuf_buffer;
-struct videobuf_queue;
-
struct videobuf_mapping {
unsigned int count;
unsigned long start;
@@ -164,6 +175,10 @@
struct timeval ts;
};
+typedef int (vb_map_sg_t)(void *dev,struct scatterlist *sglist,int nr_pages,
+ int direction);
+
+
struct videobuf_queue_ops {
int (*buf_setup)(struct videobuf_queue *q,
unsigned int *count, unsigned int *size);
@@ -174,12 +189,20 @@
struct videobuf_buffer *vb);
void (*buf_release)(struct videobuf_queue *q,
struct videobuf_buffer *vb);
+
+ /* Helper operations - device dependent.
+ * If null, videobuf_init defaults all to PCI handling
+ */
+
+ vb_map_sg_t *vb_map_sg;
+ vb_map_sg_t *vb_dma_sync_sg;
+ vb_map_sg_t *vb_unmap_sg;
};
struct videobuf_queue {
struct mutex lock;
spinlock_t *irqlock;
- struct pci_dev *pci;
+ void *dev; /* on pci, points to struct pci_dev */
enum v4l2_buf_type type;
unsigned int inputs; /* for V4L2_BUF_FLAG_INPUT */
@@ -204,12 +227,15 @@
void* videobuf_alloc(unsigned int size);
int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr);
-int videobuf_iolock(struct pci_dev *pci, struct videobuf_buffer *vb,
- struct v4l2_framebuffer *fbuf);
+int videobuf_iolock(struct videobuf_queue* q, struct videobuf_buffer *vb,
+ struct v4l2_framebuffer *fbuf);
+
+/* Maps fops to PCI stuff */
+void videobuf_queue_pci(struct videobuf_queue* q);
void videobuf_queue_init(struct videobuf_queue *q,
struct videobuf_queue_ops *ops,
- struct pci_dev *pci,
+ void *dev,
spinlock_t *irqlock,
enum v4l2_buf_type type,
enum v4l2_field field,