diff options
Diffstat (limited to 'Documentation/video4linux/videobuf')
| -rw-r--r-- | Documentation/video4linux/videobuf | 9 |
1 files changed, 2 insertions, 7 deletions
diff --git a/Documentation/video4linux/videobuf b/Documentation/video4linux/videobuf index 17a1f9abf26..3ffe9e960b6 100644 --- a/Documentation/video4linux/videobuf +++ b/Documentation/video4linux/videobuf @@ -247,8 +247,6 @@ calls. The relevant helper functions are: int nonblocking); int videobuf_streamon(struct videobuf_queue *q); int videobuf_streamoff(struct videobuf_queue *q); - int videobuf_cgmbuf(struct videobuf_queue *q, struct video_mbuf *mbuf, - int count); So, for example, a VIDIOC_REQBUFS call turns into a call to the driver's vidioc_reqbufs() callback which, in turn, usually only needs to locate the @@ -258,10 +256,7 @@ boilerplate in a lot of V4L2 drivers. The vidioc_streamon() and vidioc_streamoff() functions will be a bit more complex, of course, since they will also need to deal with starting and -stopping the capture engine. videobuf_cgmbuf(), called from the driver's -vidiocgmbuf() function, only exists if the V4L1 compatibility module has -been selected with CONFIG_VIDEO_V4L1_COMPAT, so its use must be surrounded -with #ifdef directives. +stopping the capture engine. Buffer allocation @@ -354,7 +349,7 @@ again. Developers who are interested in more information can go into the relevant header files; there are a few low-level functions declared there which have not been talked about here. Also worthwhile is the vivi driver -(drivers/media/video/vivi.c), which is maintained as an example of how V4L2 +(drivers/media/platform/vivi.c), which is maintained as an example of how V4L2 drivers should be written. Vivi only uses the vmalloc() API, but it's good enough to get started with. Note also that all of these calls are exported GPL-only, so they will not be available to non-GPL kernel modules. |