diff options
Diffstat (limited to 'Documentation/video4linux')
| -rw-r--r-- | Documentation/video4linux/v4l2-framework.txt | 30 |
1 files changed, 21 insertions, 9 deletions
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 8d2db7e09e8..48cdf86248c 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -558,26 +558,38 @@ announcing that a new buffer were filled. The irq handling code should handle the videobuf task lists, in order to advice videobuf that a new frame were filled, in order to honor to a request. The code is generally like this one: - if (list_empty(&dma_q->active)) + if (list_empty(&dma_q->active)) return; - buf = list_entry(dma_q->active.next, struct vbuffer, vb.queue); + buf = list_entry(dma_q->active.next, struct vbuffer, vb.queue); - if (!waitqueue_active(&buf->vb.done)) + if (!waitqueue_active(&buf->vb.done)) return; /* Some logic to handle the buf may be needed here */ - list_del(&buf->vb.queue); - do_gettimeofday(&buf->vb.ts); - wake_up(&buf->vb.done); + list_del(&buf->vb.queue); + do_gettimeofday(&buf->vb.ts); + wake_up(&buf->vb.done); Those are the videobuffer functions used on drivers, implemented on videobuf-core: -- videobuf_queue_core_init() - Initializes the videobuf infrastructure. This function should be - called before any other videobuf function. +- Videobuf init functions + videobuf_queue_sg_init() + Initializes the videobuf infrastructure. This function should be + called before any other videobuf function on drivers that uses DMA + Scatter/Gather buffers. + + videobuf_queue_dma_contig_init + Initializes the videobuf infrastructure. This function should be + called before any other videobuf function on drivers that need DMA + contiguous buffers. + + videobuf_queue_vmalloc_init() + Initializes the videobuf infrastructure. This function should be + called before any other videobuf function on USB (and other drivers) + that need a vmalloced type of videobuf. - videobuf_iolock() Prepares the videobuf memory for the proper method (read, mmap, overlay). |