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path: root/drivers/media/video/video-buf.c
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Diffstat (limited to 'drivers/media/video/video-buf.c')
-rw-r--r--drivers/media/video/video-buf.c1290
1 files changed, 1290 insertions, 0 deletions
diff --git a/drivers/media/video/video-buf.c b/drivers/media/video/video-buf.c
new file mode 100644
index 00000000000..5afdc785261
--- /dev/null
+++ b/drivers/media/video/video-buf.c
@@ -0,0 +1,1290 @@
+/*
+ * $Id: video-buf.c,v 1.18 2005/02/24 13:32:30 kraxel Exp $
+ *
+ * generic helper functions for video4linux capture buffers, to handle
+ * memory management and PCI DMA. Right now bttv + saa7134 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 1.1
+ * as data often must be uncompressed by the drivers).
+ *
+ * (c) 2001-2004 Gerd Knorr <kraxel@bytesex.org> [SUSE Labs]
+ *
+ * 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 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/vmalloc.h>
+#include <linux/pagemap.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+
+#include <media/video-buf.h>
+
+#define MAGIC_DMABUF 0x19721112
+#define MAGIC_BUFFER 0x20040302
+#define MAGIC_CHECK(is,should) if (unlikely((is) != (should))) \
+ { printk(KERN_ERR "magic mismatch: %x (expected %x)\n",is,should); BUG(); }
+
+static int debug = 0;
+module_param(debug, int, 0644);
+
+MODULE_DESCRIPTION("helper module to manage video4linux pci dma buffers");
+MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
+MODULE_LICENSE("GPL");
+
+#define dprintk(level, fmt, arg...) if (debug >= level) \
+ printk(KERN_DEBUG "vbuf: " fmt , ## arg)
+
+struct scatterlist*
+videobuf_vmalloc_to_sg(unsigned char *virt, int nr_pages)
+{
+ struct scatterlist *sglist;
+ struct page *pg;
+ int i;
+
+ sglist = kmalloc(sizeof(struct scatterlist)*nr_pages, GFP_KERNEL);
+ if (NULL == sglist)
+ return NULL;
+ memset(sglist,0,sizeof(struct scatterlist)*nr_pages);
+ for (i = 0; i < nr_pages; i++, virt += PAGE_SIZE) {
+ pg = vmalloc_to_page(virt);
+ if (NULL == pg)
+ goto err;
+ if (PageHighMem(pg))
+ BUG();
+ sglist[i].page = pg;
+ sglist[i].length = PAGE_SIZE;
+ }
+ return sglist;
+
+ err:
+ kfree(sglist);
+ return NULL;
+}
+
+struct scatterlist*
+videobuf_pages_to_sg(struct page **pages, int nr_pages, int offset)
+{
+ struct scatterlist *sglist;
+ int i = 0;
+
+ if (NULL == pages[0])
+ return NULL;
+ sglist = kmalloc(sizeof(*sglist) * nr_pages, GFP_KERNEL);
+ if (NULL == sglist)
+ return NULL;
+ memset(sglist, 0, sizeof(*sglist) * nr_pages);
+
+ if (NULL == pages[0])
+ goto nopage;
+ if (PageHighMem(pages[0]))
+ /* DMA to highmem pages might not work */
+ goto highmem;
+ sglist[0].page = pages[0];
+ sglist[0].offset = offset;
+ sglist[0].length = PAGE_SIZE - offset;
+ for (i = 1; i < nr_pages; i++) {
+ if (NULL == pages[i])
+ goto nopage;
+ if (PageHighMem(pages[i]))
+ goto highmem;
+ sglist[i].page = pages[i];
+ sglist[i].length = PAGE_SIZE;
+ }
+ return sglist;
+
+ nopage:
+ dprintk(2,"sgl: oops - no page\n");
+ kfree(sglist);
+ return NULL;
+
+ highmem:
+ dprintk(2,"sgl: oops - highmem page\n");
+ kfree(sglist);
+ return NULL;
+}
+
+/* --------------------------------------------------------------------- */
+
+void videobuf_dma_init(struct videobuf_dmabuf *dma)
+{
+ memset(dma,0,sizeof(*dma));
+ dma->magic = MAGIC_DMABUF;
+}
+
+int videobuf_dma_init_user(struct videobuf_dmabuf *dma, int direction,
+ unsigned long data, unsigned long size)
+{
+ unsigned long first,last;
+ int err, rw = 0;
+
+ dma->direction = direction;
+ switch (dma->direction) {
+ case PCI_DMA_FROMDEVICE: rw = READ; break;
+ case PCI_DMA_TODEVICE: rw = WRITE; break;
+ default: BUG();
+ }
+
+ first = (data & PAGE_MASK) >> PAGE_SHIFT;
+ last = ((data+size-1) & PAGE_MASK) >> PAGE_SHIFT;
+ dma->offset = data & ~PAGE_MASK;
+ dma->nr_pages = last-first+1;
+ dma->pages = kmalloc(dma->nr_pages * sizeof(struct page*),
+ GFP_KERNEL);
+ if (NULL == dma->pages)
+ return -ENOMEM;
+ dprintk(1,"init user [0x%lx+0x%lx => %d pages]\n",
+ data,size,dma->nr_pages);
+
+ down_read(&current->mm->mmap_sem);
+ err = get_user_pages(current,current->mm,
+ data & PAGE_MASK, dma->nr_pages,
+ rw == READ, 1, /* force */
+ dma->pages, NULL);
+ up_read(&current->mm->mmap_sem);
+ if (err != dma->nr_pages) {
+ dma->nr_pages = (err >= 0) ? err : 0;
+ dprintk(1,"get_user_pages: err=%d [%d]\n",err,dma->nr_pages);
+ return err < 0 ? err : -EINVAL;
+ }
+ return 0;
+}
+
+int videobuf_dma_init_kernel(struct videobuf_dmabuf *dma, int direction,
+ int nr_pages)
+{
+ dprintk(1,"init kernel [%d pages]\n",nr_pages);
+ dma->direction = direction;
+ dma->vmalloc = vmalloc_32(nr_pages << PAGE_SHIFT);
+ if (NULL == dma->vmalloc) {
+ dprintk(1,"vmalloc_32(%d pages) failed\n",nr_pages);
+ return -ENOMEM;
+ }
+ memset(dma->vmalloc,0,nr_pages << PAGE_SHIFT);
+ dma->nr_pages = nr_pages;
+ return 0;
+}
+
+int videobuf_dma_init_overlay(struct videobuf_dmabuf *dma, int direction,
+ dma_addr_t addr, int nr_pages)
+{
+ dprintk(1,"init overlay [%d pages @ bus 0x%lx]\n",
+ nr_pages,(unsigned long)addr);
+ dma->direction = direction;
+ if (0 == addr)
+ return -EINVAL;
+
+ dma->bus_addr = addr;
+ dma->nr_pages = nr_pages;
+ return 0;
+}
+
+int videobuf_dma_pci_map(struct pci_dev *dev, struct videobuf_dmabuf *dma)
+{
+ MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
+ BUG_ON(0 == dma->nr_pages);
+
+ if (dma->pages) {
+ dma->sglist = videobuf_pages_to_sg(dma->pages, dma->nr_pages,
+ dma->offset);
+ }
+ if (dma->vmalloc) {
+ dma->sglist = videobuf_vmalloc_to_sg
+ (dma->vmalloc,dma->nr_pages);
+ }
+ if (dma->bus_addr) {
+ dma->sglist = kmalloc(sizeof(struct scatterlist), GFP_KERNEL);
+ if (NULL != dma->sglist) {
+ dma->sglen = 1;
+ sg_dma_address(&dma->sglist[0]) = dma->bus_addr & PAGE_MASK;
+ dma->sglist[0].offset = dma->bus_addr & ~PAGE_MASK;
+ sg_dma_len(&dma->sglist[0]) = dma->nr_pages * PAGE_SIZE;
+ }
+ }
+ if (NULL == dma->sglist) {
+ dprintk(1,"scatterlist is NULL\n");
+ return -ENOMEM;
+ }
+
+ if (!dma->bus_addr) {
+ dma->sglen = pci_map_sg(dev,dma->sglist,dma->nr_pages,
+ dma->direction);
+ if (0 == dma->sglen) {
+ printk(KERN_WARNING
+ "%s: pci_map_sg failed\n",__FUNCTION__);
+ kfree(dma->sglist);
+ dma->sglist = NULL;
+ dma->sglen = 0;
+ return -EIO;
+ }
+ }
+ return 0;
+}
+
+int videobuf_dma_pci_sync(struct pci_dev *dev, struct videobuf_dmabuf *dma)
+{
+ MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
+ BUG_ON(!dma->sglen);
+
+ if (!dma->bus_addr)
+ pci_dma_sync_sg_for_cpu(dev,dma->sglist,dma->nr_pages,dma->direction);
+ return 0;
+}
+
+int videobuf_dma_pci_unmap(struct pci_dev *dev, struct videobuf_dmabuf *dma)
+{
+ MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
+ if (!dma->sglen)
+ return 0;
+
+ if (!dma->bus_addr)
+ pci_unmap_sg(dev,dma->sglist,dma->nr_pages,dma->direction);
+ kfree(dma->sglist);
+ dma->sglist = NULL;
+ dma->sglen = 0;
+ return 0;
+}
+
+int videobuf_dma_free(struct videobuf_dmabuf *dma)
+{
+ MAGIC_CHECK(dma->magic,MAGIC_DMABUF);
+ BUG_ON(dma->sglen);
+
+ if (dma->pages) {
+ int i;
+ for (i=0; i < dma->nr_pages; i++)
+ page_cache_release(dma->pages[i]);
+ kfree(dma->pages);
+ dma->pages = NULL;
+ }
+ if (dma->vmalloc) {
+ vfree(dma->vmalloc);
+ dma->vmalloc = NULL;
+ }
+ if (dma->bus_addr) {
+ dma->bus_addr = 0;
+ }
+ dma->direction = PCI_DMA_NONE;
+ return 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+void* videobuf_alloc(unsigned int size)
+{
+ struct videobuf_buffer *vb;
+
+ vb = kmalloc(size,GFP_KERNEL);
+ if (NULL != vb) {
+ memset(vb,0,size);
+ videobuf_dma_init(&vb->dma);
+ init_waitqueue_head(&vb->done);
+ vb->magic = MAGIC_BUFFER;
+ }
+ return vb;
+}
+
+int videobuf_waiton(struct videobuf_buffer *vb, int non_blocking, int intr)
+{
+ int retval = 0;
+ DECLARE_WAITQUEUE(wait, current);
+
+ MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
+ add_wait_queue(&vb->done, &wait);
+ while (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED) {
+ if (non_blocking) {
+ retval = -EAGAIN;
+ break;
+ }
+ set_current_state(intr ? TASK_INTERRUPTIBLE
+ : TASK_UNINTERRUPTIBLE);
+ if (vb->state == STATE_ACTIVE || vb->state == STATE_QUEUED)
+ schedule();
+ set_current_state(TASK_RUNNING);
+ if (intr && signal_pending(current)) {
+ dprintk(1,"buffer waiton: -EINTR\n");
+ retval = -EINTR;
+ break;
+ }
+ }
+ remove_wait_queue(&vb->done, &wait);
+ return retval;
+}
+
+int
+videobuf_iolock(struct pci_dev *pci, struct videobuf_buffer *vb,
+ struct v4l2_framebuffer *fbuf)
+{
+ int err,pages;
+ dma_addr_t bus;
+
+ MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
+ switch (vb->memory) {
+ case V4L2_MEMORY_MMAP:
+ case V4L2_MEMORY_USERPTR:
+ if (0 == vb->baddr) {
+ /* no userspace addr -- kernel bounce buffer */
+ pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
+ err = videobuf_dma_init_kernel(&vb->dma,PCI_DMA_FROMDEVICE,
+ pages);
+ if (0 != err)
+ return err;
+ } else {
+ /* dma directly to userspace */
+ err = videobuf_dma_init_user(&vb->dma,PCI_DMA_FROMDEVICE,
+ vb->baddr,vb->bsize);
+ if (0 != err)
+ return err;
+ }
+ break;
+ case V4L2_MEMORY_OVERLAY:
+ if (NULL == fbuf)
+ return -EINVAL;
+ /* FIXME: need sanity checks for vb->boff */
+ bus = (dma_addr_t)fbuf->base + vb->boff;
+ pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
+ err = videobuf_dma_init_overlay(&vb->dma,PCI_DMA_FROMDEVICE,
+ bus, pages);
+ if (0 != err)
+ return err;
+ break;
+ default:
+ BUG();
+ }
+ err = videobuf_dma_pci_map(pci,&vb->dma);
+ if (0 != err)
+ return err;
+
+ return 0;
+}
+
+/* --------------------------------------------------------------------- */
+
+void videobuf_queue_init(struct videobuf_queue* q,
+ struct videobuf_queue_ops *ops,
+ struct pci_dev *pci,
+ spinlock_t *irqlock,
+ enum v4l2_buf_type type,
+ enum v4l2_field field,
+ unsigned int msize,
+ void *priv)
+{
+ memset(q,0,sizeof(*q));
+ q->irqlock = irqlock;
+ q->pci = pci;
+ q->type = type;
+ q->field = field;
+ q->msize = msize;
+ q->ops = ops;
+ q->priv_data = priv;
+
+ init_MUTEX(&q->lock);
+ INIT_LIST_HEAD(&q->stream);
+}
+
+int
+videobuf_queue_is_busy(struct videobuf_queue *q)
+{
+ int i;
+
+ if (q->streaming) {
+ dprintk(1,"busy: streaming active\n");
+ return 1;
+ }
+ if (q->reading) {
+ dprintk(1,"busy: pending read #1\n");
+ return 1;
+ }
+ if (q->read_buf) {
+ dprintk(1,"busy: pending read #2\n");
+ return 1;
+ }
+ for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+ if (NULL == q->bufs[i])
+ continue;
+ if (q->bufs[i]->map) {
+ dprintk(1,"busy: buffer #%d mapped\n",i);
+ return 1;
+ }
+ if (q->bufs[i]->state == STATE_QUEUED) {
+ dprintk(1,"busy: buffer #%d queued\n",i);
+ return 1;
+ }
+ if (q->bufs[i]->state == STATE_ACTIVE) {
+ dprintk(1,"busy: buffer #%d avtive\n",i);
+ return 1;
+ }
+ }
+ return 0;
+}
+
+void
+videobuf_queue_cancel(struct videobuf_queue *q)
+{
+ unsigned long flags;
+ int i;
+
+ /* remove queued buffers from list */
+ spin_lock_irqsave(q->irqlock,flags);
+ for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+ if (NULL == q->bufs[i])
+ continue;
+ if (q->bufs[i]->state == STATE_QUEUED) {
+ list_del(&q->bufs[i]->queue);
+ q->bufs[i]->state = STATE_ERROR;
+ }
+ }
+ spin_unlock_irqrestore(q->irqlock,flags);
+
+ /* free all buffers + clear queue */
+ for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+ if (NULL == q->bufs[i])
+ continue;
+ q->ops->buf_release(q,q->bufs[i]);
+ }
+ INIT_LIST_HEAD(&q->stream);
+}
+
+/* --------------------------------------------------------------------- */
+
+enum v4l2_field
+videobuf_next_field(struct videobuf_queue *q)
+{
+ enum v4l2_field field = q->field;
+
+ BUG_ON(V4L2_FIELD_ANY == field);
+
+ if (V4L2_FIELD_ALTERNATE == field) {
+ if (V4L2_FIELD_TOP == q->last) {
+ field = V4L2_FIELD_BOTTOM;
+ q->last = V4L2_FIELD_BOTTOM;
+ } else {
+ field = V4L2_FIELD_TOP;
+ q->last = V4L2_FIELD_TOP;
+ }
+ }
+ return field;
+}
+
+void
+videobuf_status(struct v4l2_buffer *b, struct videobuf_buffer *vb,
+ enum v4l2_buf_type type)
+{
+ MAGIC_CHECK(vb->magic,MAGIC_BUFFER);
+
+ b->index = vb->i;
+ b->type = type;
+
+ b->memory = vb->memory;
+ switch (b->memory) {
+ case V4L2_MEMORY_MMAP:
+ b->m.offset = vb->boff;
+ b->length = vb->bsize;
+ break;
+ case V4L2_MEMORY_USERPTR:
+ b->m.userptr = vb->baddr;
+ b->length = vb->bsize;
+ break;
+ case V4L2_MEMORY_OVERLAY:
+ b->m.offset = vb->boff;
+ break;
+ }
+
+ b->flags = 0;
+ if (vb->map)
+ b->flags |= V4L2_BUF_FLAG_MAPPED;
+
+ switch (vb->state) {
+ case STATE_PREPARED:
+ case STATE_QUEUED:
+ case STATE_ACTIVE:
+ b->flags |= V4L2_BUF_FLAG_QUEUED;
+ break;
+ case STATE_DONE:
+ case STATE_ERROR:
+ b->flags |= V4L2_BUF_FLAG_DONE;
+ break;
+ case STATE_NEEDS_INIT:
+ case STATE_IDLE:
+ /* nothing */
+ break;
+ }
+
+ if (vb->input != UNSET) {
+ b->flags |= V4L2_BUF_FLAG_INPUT;
+ b->input = vb->input;
+ }
+
+ b->field = vb->field;
+ b->timestamp = vb->ts;
+ b->bytesused = vb->size;
+ b->sequence = vb->field_count >> 1;
+}
+
+int
+videobuf_reqbufs(struct videobuf_queue *q,
+ struct v4l2_requestbuffers *req)
+{
+ unsigned int size,count;
+ int retval;
+
+ if (req->type != q->type)
+ return -EINVAL;
+ if (req->count < 1)
+ return -EINVAL;
+ if (req->memory != V4L2_MEMORY_MMAP &&
+ req->memory != V4L2_MEMORY_USERPTR &&
+ req->memory != V4L2_MEMORY_OVERLAY)
+ return -EINVAL;
+
+ if (q->streaming)
+ return -EBUSY;
+ if (!list_empty(&q->stream))
+ return -EBUSY;
+
+ down(&q->lock);
+ count = req->count;
+ if (count > VIDEO_MAX_FRAME)
+ count = VIDEO_MAX_FRAME;
+ size = 0;
+ q->ops->buf_setup(q,&count,&size);
+ size = PAGE_ALIGN(size);
+ dprintk(1,"reqbufs: bufs=%d, size=0x%x [%d pages total]\n",
+ count, size, (count*size)>>PAGE_SHIFT);
+
+ retval = videobuf_mmap_setup(q,count,size,req->memory);
+ if (retval < 0)
+ goto done;
+
+ req->count = count;
+
+ done:
+ up(&q->lock);
+ return retval;
+}
+
+int
+videobuf_querybuf(struct videobuf_queue *q, struct v4l2_buffer *b)
+{
+ if (unlikely(b->type != q->type))
+ return -EINVAL;
+ if (unlikely(b->index < 0 || b->index >= VIDEO_MAX_FRAME))
+ return -EINVAL;
+ if (unlikely(NULL == q->bufs[b->index]))
+ return -EINVAL;
+ videobuf_status(b,q->bufs[b->index],q->type);
+ return 0;
+}
+
+int
+videobuf_qbuf(struct videobuf_queue *q,
+ struct v4l2_buffer *b)
+{
+ struct videobuf_buffer *buf;
+ enum v4l2_field field;
+ unsigned long flags;
+ int retval;
+
+ down(&q->lock);
+ retval = -EBUSY;
+ if (q->reading)
+ goto done;
+ retval = -EINVAL;
+ if (b->type != q->type)
+ goto done;
+ if (b->index < 0 || b->index >= VIDEO_MAX_FRAME)
+ goto done;
+ buf = q->bufs[b->index];
+ if (NULL == buf)
+ goto done;
+ MAGIC_CHECK(buf->magic,MAGIC_BUFFER);
+ if (buf->memory != b->memory)
+ goto done;
+ if (buf->state == STATE_QUEUED ||
+ buf->state == STATE_ACTIVE)
+ goto done;
+
+ if (b->flags & V4L2_BUF_FLAG_INPUT) {
+ if (b->input >= q->inputs)
+ goto done;
+ buf->input = b->input;
+ } else {
+ buf->input = UNSET;
+ }
+
+ switch (b->memory) {
+ case V4L2_MEMORY_MMAP:
+ if (0 == buf->baddr)
+ goto done;
+ break;
+ case V4L2_MEMORY_USERPTR:
+ if (b->length < buf->bsize)
+ goto done;
+ if (STATE_NEEDS_INIT != buf->state && buf->baddr != b->m.userptr)
+ q->ops->buf_release(q,buf);
+ buf->baddr = b->m.userptr;
+ break;
+ case V4L2_MEMORY_OVERLAY:
+ buf->boff = b->m.offset;
+ break;
+ default:
+ goto done;
+ }
+
+ field = videobuf_next_field(q);
+ retval = q->ops->buf_prepare(q,buf,field);
+ if (0 != retval)
+ goto done;
+
+ list_add_tail(&buf->stream,&q->stream);
+ if (q->streaming) {
+ spin_lock_irqsave(q->irqlock,flags);
+ q->ops->buf_queue(q,buf);
+ spin_unlock_irqrestore(q->irqlock,flags);
+ }
+ retval = 0;
+
+ done:
+ up(&q->lock);
+ return retval;
+}
+
+int
+videobuf_dqbuf(struct videobuf_queue *q,
+ struct v4l2_buffer *b, int nonblocking)
+{
+ struct videobuf_buffer *buf;
+ int retval;
+
+ down(&q->lock);
+ retval = -EBUSY;
+ if (q->reading)
+ goto done;
+ retval = -EINVAL;
+ if (b->type != q->type)
+ goto done;
+ if (list_empty(&q->stream))
+ goto done;
+ buf = list_entry(q->stream.next, struct videobuf_buffer, stream);
+ retval = videobuf_waiton(buf, nonblocking, 1);
+ if (retval < 0)
+ goto done;
+ switch (buf->state) {
+ case STATE_ERROR:
+ retval = -EIO;
+ /* fall through */
+ case STATE_DONE:
+ videobuf_dma_pci_sync(q->pci,&buf->dma);
+ buf->state = STATE_IDLE;
+ break;
+ default:
+ retval = -EINVAL;
+ goto done;
+ }
+ list_del(&buf->stream);
+ memset(b,0,sizeof(*b));
+ videobuf_status(b,buf,q->type);
+
+ done:
+ up(&q->lock);
+ return retval;
+}
+
+int videobuf_streamon(struct videobuf_queue *q)
+{
+ struct videobuf_buffer *buf;
+ struct list_head *list;
+ unsigned long flags;
+ int retval;
+
+ down(&q->lock);
+ retval = -EBUSY;
+ if (q->reading)
+ goto done;
+ retval = 0;
+ if (q->streaming)
+ goto done;
+ q->streaming = 1;
+ spin_lock_irqsave(q->irqlock,flags);
+ list_for_each(list,&q->stream) {
+ buf = list_entry(list, struct videobuf_buffer, stream);
+ if (buf->state == STATE_PREPARED)
+ q->ops->buf_queue(q,buf);
+ }
+ spin_unlock_irqrestore(q->irqlock,flags);
+
+ done:
+ up(&q->lock);
+ return retval;
+}
+
+int videobuf_streamoff(struct videobuf_queue *q)
+{
+ int retval = -EINVAL;
+
+ down(&q->lock);
+ if (!q->streaming)
+ goto done;
+ videobuf_queue_cancel(q);
+ q->streaming = 0;
+ retval = 0;
+
+ done:
+ up(&q->lock);
+ return retval;
+}
+
+static ssize_t
+videobuf_read_zerocopy(struct videobuf_queue *q, char __user *data,
+ size_t count, loff_t *ppos)
+{
+ enum v4l2_field field;
+ unsigned long flags;
+ int retval;
+
+ /* setup stuff */
+ retval = -ENOMEM;
+ q->read_buf = videobuf_alloc(q->msize);
+ if (NULL == q->read_buf)
+ goto done;
+
+ q->read_buf->memory = V4L2_MEMORY_USERPTR;
+ q->read_buf->baddr = (unsigned long)data;
+ q->read_buf->bsize = count;
+ field = videobuf_next_field(q);
+ retval = q->ops->buf_prepare(q,q->read_buf,field);
+ if (0 != retval)
+ goto done;
+
+ /* start capture & wait */
+ spin_lock_irqsave(q->irqlock,flags);
+ q->ops->buf_queue(q,q->read_buf);
+ spin_unlock_irqrestore(q->irqlock,flags);
+ retval = videobuf_waiton(q->read_buf,0,0);
+ if (0 == retval) {
+ videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
+ if (STATE_ERROR == q->read_buf->state)
+ retval = -EIO;
+ else
+ retval = q->read_buf->size;
+ }
+
+ done:
+ /* cleanup */
+ q->ops->buf_release(q,q->read_buf);
+ kfree(q->read_buf);
+ q->read_buf = NULL;
+ return retval;
+}
+
+ssize_t videobuf_read_one(struct videobuf_queue *q,
+ char __user *data, size_t count, loff_t *ppos,
+ int nonblocking)
+{
+ enum v4l2_field field;
+ unsigned long flags;
+ unsigned size, nbufs, bytes;
+ int retval;
+
+ down(&q->lock);
+
+ nbufs = 1; size = 0;
+ q->ops->buf_setup(q,&nbufs,&size);
+ if (NULL == q->read_buf &&
+ count >= size &&
+ !nonblocking) {
+ retval = videobuf_read_zerocopy(q,data,count,ppos);
+ if (retval >= 0 || retval == -EIO)
+ /* ok, all done */
+ goto done;
+ /* fallback to kernel bounce buffer on failures */
+ }
+
+ if (NULL == q->read_buf) {
+ /* need to capture a new frame */
+ retval = -ENOMEM;
+ q->read_buf = videobuf_alloc(q->msize);
+ if (NULL == q->read_buf)
+ goto done;
+ q->read_buf->memory = V4L2_MEMORY_USERPTR;
+ field = videobuf_next_field(q);
+ retval = q->ops->buf_prepare(q,q->read_buf,field);
+ if (0 != retval)
+ goto done;
+ spin_lock_irqsave(q->irqlock,flags);
+ q->ops->buf_queue(q,q->read_buf);
+ spin_unlock_irqrestore(q->irqlock,flags);
+ q->read_off = 0;
+ }
+
+ /* wait until capture is done */
+ retval = videobuf_waiton(q->read_buf, nonblocking, 1);
+ if (0 != retval)
+ goto done;
+ videobuf_dma_pci_sync(q->pci,&q->read_buf->dma);
+
+ if (STATE_ERROR == q->read_buf->state) {
+ /* catch I/O errors */
+ q->ops->buf_release(q,q->read_buf);
+ kfree(q->read_buf);
+ q->read_buf = NULL;
+ retval = -EIO;
+ goto done;
+ }
+
+ /* copy to userspace */
+ bytes = count;
+ if (bytes > q->read_buf->size - q->read_off)
+ bytes = q->read_buf->size - q->read_off;
+ retval = -EFAULT;
+ if (copy_to_user(data, q->read_buf->dma.vmalloc+q->read_off, bytes))
+ goto done;
+
+ retval = bytes;
+ q->read_off += bytes;
+ if (q->read_off == q->read_buf->size) {
+ /* all data copied, cleanup */
+ q->ops->buf_release(q,q->read_buf);
+ kfree(q->read_buf);
+ q->read_buf = NULL;
+ }
+
+ done:
+ up(&q->lock);
+ return retval;
+}
+
+int videobuf_read_start(struct videobuf_queue *q)
+{
+ enum v4l2_field field;
+ unsigned long flags;
+ int count = 0, size = 0;
+ int err, i;
+
+ q->ops->buf_setup(q,&count,&size);
+ if (count < 2)
+ count = 2;
+ if (count > VIDEO_MAX_FRAME)
+ count = VIDEO_MAX_FRAME;
+ size = PAGE_ALIGN(size);
+
+ err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
+ if (err)
+ return err;
+ for (i = 0; i < count; i++) {
+ field = videobuf_next_field(q);
+ err = q->ops->buf_prepare(q,q->bufs[i],field);
+ if (err)
+ return err;
+ list_add_tail(&q->bufs[i]->stream, &q->stream);
+ }
+ spin_lock_irqsave(q->irqlock,flags);
+ for (i = 0; i < count; i++)
+ q->ops->buf_queue(q,q->bufs[i]);
+ spin_unlock_irqrestore(q->irqlock,flags);
+ q->reading = 1;
+ return 0;
+}
+
+void videobuf_read_stop(struct videobuf_queue *q)
+{
+ int i;
+
+ videobuf_queue_cancel(q);
+ videobuf_mmap_free(q);
+ INIT_LIST_HEAD(&q->stream);
+ for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+ if (NULL == q->bufs[i])
+ continue;
+ kfree(q->bufs[i]);
+ q->bufs[i] = NULL;
+ }
+ q->read_buf = NULL;
+ q->reading = 0;
+}
+
+ssize_t videobuf_read_stream(struct videobuf_queue *q,
+ char __user *data, size_t count, loff_t *ppos,
+ int vbihack, int nonblocking)
+{
+ unsigned int *fc, bytes;
+ int err, retval;
+ unsigned long flags;
+
+ dprintk(2,"%s\n",__FUNCTION__);
+ down(&q->lock);
+ retval = -EBUSY;
+ if (q->streaming)
+ goto done;
+ if (!q->reading) {
+ retval = videobuf_read_start(q);
+ if (retval < 0)
+ goto done;
+ }
+
+ retval = 0;
+ while (count > 0) {
+ /* get / wait for data */
+ if (NULL == q->read_buf) {
+ q->read_buf = list_entry(q->stream.next,
+ struct videobuf_buffer,
+ stream);
+ list_del(&q->read_buf->stream);
+ q->read_off = 0;
+ }
+ err = videobuf_waiton(q->read_buf, nonblocking, 1);
+ if (err < 0) {
+ if (0 == retval)
+ retval = err;
+ break;
+ }
+
+ if (q->read_buf->state == STATE_DONE) {
+ if (vbihack) {
+ /* dirty, undocumented hack -- pass the frame counter
+ * within the last four bytes of each vbi data block.
+ * We need that one to maintain backward compatibility
+ * to all vbi decoding software out there ... */
+ fc = (unsigned int*)q->read_buf->dma.vmalloc;
+ fc += (q->read_buf->size>>2) -1;
+ *fc = q->read_buf->field_count >> 1;
+ dprintk(1,"vbihack: %d\n",*fc);
+ }
+
+ /* copy stuff */
+ bytes = count;
+ if (bytes > q->read_buf->size - q->read_off)
+ bytes = q->read_buf->size - q->read_off;
+ if (copy_to_user(data + retval,
+ q->read_buf->dma.vmalloc + q->read_off,
+ bytes)) {
+ if (0 == retval)
+ retval = -EFAULT;
+ break;
+ }
+ count -= bytes;
+ retval += bytes;
+ q->read_off += bytes;
+ } else {
+ /* some error */
+ q->read_off = q->read_buf->size;
+ if (0 == retval)
+ retval = -EIO;
+ }
+
+ /* requeue buffer when done with copying */
+ if (q->read_off == q->read_buf->size) {
+ list_add_tail(&q->read_buf->stream,
+ &q->stream);
+ spin_lock_irqsave(q->irqlock,flags);
+ q->ops->buf_queue(q,q->read_buf);
+ spin_unlock_irqrestore(q->irqlock,flags);
+ q->read_buf = NULL;
+ }
+ if (retval < 0)
+ break;
+ }
+
+ done:
+ up(&q->lock);
+ return retval;
+}
+
+unsigned int videobuf_poll_stream(struct file *file,
+ struct videobuf_queue *q,
+ poll_table *wait)
+{
+ struct videobuf_buffer *buf = NULL;
+ unsigned int rc = 0;
+
+ down(&q->lock);
+ if (q->streaming) {
+ if (!list_empty(&q->stream))
+ buf = list_entry(q->stream.next,
+ struct videobuf_buffer, stream);
+ } else {
+ if (!q->reading)
+ videobuf_read_start(q);
+ if (!q->reading) {
+ rc = POLLERR;
+ } else if (NULL == q->read_buf) {
+ q->read_buf = list_entry(q->stream.next,
+ struct videobuf_buffer,
+ stream);
+ list_del(&q->read_buf->stream);
+ q->read_off = 0;
+ }
+ buf = q->read_buf;
+ }
+ if (!buf)
+ rc = POLLERR;
+
+ if (0 == rc) {
+ poll_wait(file, &buf->done, wait);
+ if (buf->state == STATE_DONE ||
+ buf->state == STATE_ERROR)
+ rc = POLLIN|POLLRDNORM;
+ }
+ up(&q->lock);
+ return rc;
+}
+
+/* --------------------------------------------------------------------- */
+
+static void
+videobuf_vm_open(struct vm_area_struct *vma)
+{
+ struct videobuf_mapping *map = vma->vm_private_data;
+
+ dprintk(2,"vm_open %p [count=%d,vma=%08lx-%08lx]\n",map,
+ map->count,vma->vm_start,vma->vm_end);
+ map->count++;
+}
+
+static void
+videobuf_vm_close(struct vm_area_struct *vma)
+{
+ struct videobuf_mapping *map = vma->vm_private_data;
+ struct videobuf_queue *q = map->q;
+ int i;
+
+ dprintk(2,"vm_close %p [count=%d,vma=%08lx-%08lx]\n",map,
+ map->count,vma->vm_start,vma->vm_end);
+
+ map->count--;
+ if (0 == map->count) {
+ dprintk(1,"munmap %p q=%p\n",map,q);
+ down(&q->lock);
+ for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+ if (NULL == q->bufs[i])
+ continue;
+ if (q->bufs[i])
+ ;
+ if (q->bufs[i]->map != map)
+ continue;
+ q->bufs[i]->map = NULL;
+ q->bufs[i]->baddr = 0;
+ q->ops->buf_release(q,q->bufs[i]);
+ }
+ up(&q->lock);
+ kfree(map);
+ }
+ return;
+}
+
+/*
+ * Get a anonymous page for the mapping. Make sure we can DMA to that
+ * memory location with 32bit PCI devices (i.e. don't use highmem for
+ * now ...). Bounce buffers don't work very well for the data rates
+ * video capture has.
+ */
+static struct page*
+videobuf_vm_nopage(struct vm_area_struct *vma, unsigned long vaddr,
+ int *type)
+{
+ struct page *page;
+
+ dprintk(3,"nopage: fault @ %08lx [vma %08lx-%08lx]\n",
+ vaddr,vma->vm_start,vma->vm_end);
+ if (vaddr > vma->vm_end)
+ return NOPAGE_SIGBUS;
+ page = alloc_page(GFP_USER);
+ if (!page)
+ return NOPAGE_OOM;
+ clear_user_page(page_address(page), vaddr, page);
+ if (type)
+ *type = VM_FAULT_MINOR;
+ return page;
+}
+
+static struct vm_operations_struct videobuf_vm_ops =
+{
+ .open = videobuf_vm_open,
+ .close = videobuf_vm_close,
+ .nopage = videobuf_vm_nopage,
+};
+
+int videobuf_mmap_setup(struct videobuf_queue *q,
+ unsigned int bcount, unsigned int bsize,
+ enum v4l2_memory memory)
+{
+ unsigned int i;
+ int err;
+
+ err = videobuf_mmap_free(q);
+ if (0 != err)
+ return err;
+
+ for (i = 0; i < bcount; i++) {
+ q->bufs[i] = videobuf_alloc(q->msize);
+ q->bufs[i]->i = i;
+ q->bufs[i]->input = UNSET;
+ q->bufs[i]->memory = memory;
+ q->bufs[i]->bsize = bsize;
+ switch (memory) {
+ case V4L2_MEMORY_MMAP:
+ q->bufs[i]->boff = bsize * i;
+ break;
+ case V4L2_MEMORY_USERPTR:
+ case V4L2_MEMORY_OVERLAY:
+ /* nothing */
+ break;
+ }
+ }
+ dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
+ bcount,bsize);
+ return 0;
+}
+
+int videobuf_mmap_free(struct videobuf_queue *q)
+{
+ int i;
+
+ for (i = 0; i < VIDEO_MAX_FRAME; i++)
+ if (q->bufs[i] && q->bufs[i]->map)
+ return -EBUSY;
+ for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+ if (NULL == q->bufs[i])
+ continue;
+ q->ops->buf_release(q,q->bufs[i]);
+ kfree(q->bufs[i]);
+ q->bufs[i] = NULL;
+ }
+ return 0;
+}
+
+int videobuf_mmap_mapper(struct videobuf_queue *q,
+ struct vm_area_struct *vma)
+{
+ struct videobuf_mapping *map;
+ unsigned int first,last,size,i;
+ int retval;
+
+ down(&q->lock);
+ retval = -EINVAL;
+ if (!(vma->vm_flags & VM_WRITE)) {
+ dprintk(1,"mmap app bug: PROT_WRITE please\n");
+ goto done;
+ }
+ if (!(vma->vm_flags & VM_SHARED)) {
+ dprintk(1,"mmap app bug: MAP_SHARED please\n");
+ goto done;
+ }
+
+ /* look for first buffer to map */
+ for (first = 0; first < VIDEO_MAX_FRAME; first++) {
+ if (NULL == q->bufs[first])
+ continue;
+ if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
+ continue;
+ if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
+ break;
+ }
+ if (VIDEO_MAX_FRAME == first) {
+ dprintk(1,"mmap app bug: offset invalid [offset=0x%lx]\n",
+ (vma->vm_pgoff << PAGE_SHIFT));
+ goto done;
+ }
+
+ /* look for last buffer to map */
+ for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
+ if (NULL == q->bufs[last])
+ continue;
+ if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
+ continue;
+ if (q->bufs[last]->map) {
+ retval = -EBUSY;
+ goto done;
+ }
+ size += q->bufs[last]->bsize;
+ if (size == (vma->vm_end - vma->vm_start))
+ break;
+ }
+ if (VIDEO_MAX_FRAME == last) {
+ dprintk(1,"mmap app bug: size invalid [size=0x%lx]\n",
+ (vma->vm_end - vma->vm_start));
+ goto done;
+ }
+
+ /* create mapping + update buffer list */
+ retval = -ENOMEM;
+ map = kmalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
+ if (NULL == map)
+ goto done;
+ for (size = 0, i = first; i <= last; size += q->bufs[i++]->bsize) {
+ q->bufs[i]->map = map;
+ q->bufs[i]->baddr = vma->vm_start + size;
+ }
+ map->count = 1;
+ map->start = vma->vm_start;
+ map->end = vma->vm_end;
+ map->q = q;
+ vma->vm_ops = &videobuf_vm_ops;
+ vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
+ vma->vm_flags &= ~VM_IO; /* using shared anonymous pages */
+ vma->vm_private_data = map;
+ dprintk(1,"mmap %p: q=%p %08lx-%08lx pgoff %08lx bufs %d-%d\n",
+ map,q,vma->vm_start,vma->vm_end,vma->vm_pgoff,first,last);
+ retval = 0;
+
+ done:
+ up(&q->lock);
+ return retval;
+}
+
+/* --------------------------------------------------------------------- */
+
+EXPORT_SYMBOL_GPL(videobuf_vmalloc_to_sg);
+
+EXPORT_SYMBOL_GPL(videobuf_dma_init);
+EXPORT_SYMBOL_GPL(videobuf_dma_init_user);
+EXPORT_SYMBOL_GPL(videobuf_dma_init_kernel);
+EXPORT_SYMBOL_GPL(videobuf_dma_init_overlay);
+EXPORT_SYMBOL_GPL(videobuf_dma_pci_map);
+EXPORT_SYMBOL_GPL(videobuf_dma_pci_sync);
+EXPORT_SYMBOL_GPL(videobuf_dma_pci_unmap);
+EXPORT_SYMBOL_GPL(videobuf_dma_free);
+
+EXPORT_SYMBOL_GPL(videobuf_alloc);
+EXPORT_SYMBOL_GPL(videobuf_waiton);
+EXPORT_SYMBOL_GPL(videobuf_iolock);
+
+EXPORT_SYMBOL_GPL(videobuf_queue_init);
+EXPORT_SYMBOL_GPL(videobuf_queue_cancel);
+EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
+
+EXPORT_SYMBOL_GPL(videobuf_next_field);
+EXPORT_SYMBOL_GPL(videobuf_status);
+EXPORT_SYMBOL_GPL(videobuf_reqbufs);
+EXPORT_SYMBOL_GPL(videobuf_querybuf);
+EXPORT_SYMBOL_GPL(videobuf_qbuf);
+EXPORT_SYMBOL_GPL(videobuf_dqbuf);
+EXPORT_SYMBOL_GPL(videobuf_streamon);
+EXPORT_SYMBOL_GPL(videobuf_streamoff);
+
+EXPORT_SYMBOL_GPL(videobuf_read_start);
+EXPORT_SYMBOL_GPL(videobuf_read_stop);
+EXPORT_SYMBOL_GPL(videobuf_read_stream);
+EXPORT_SYMBOL_GPL(videobuf_read_one);
+EXPORT_SYMBOL_GPL(videobuf_poll_stream);
+
+EXPORT_SYMBOL_GPL(videobuf_mmap_setup);
+EXPORT_SYMBOL_GPL(videobuf_mmap_free);
+EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);
+
+/*
+ * Local variables:
+ * c-basic-offset: 8
+ * End:
+ */