diff options
Diffstat (limited to 'Documentation/DocBook/v4l/vidioc-querybuf.xml')
| -rw-r--r-- | Documentation/DocBook/v4l/vidioc-querybuf.xml | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/Documentation/DocBook/v4l/vidioc-querybuf.xml b/Documentation/DocBook/v4l/vidioc-querybuf.xml index d834993e6191..e649805a4908 100644 --- a/Documentation/DocBook/v4l/vidioc-querybuf.xml +++ b/Documentation/DocBook/v4l/vidioc-querybuf.xml @@ -54,12 +54,13 @@ buffer at any time after buffers have been allocated with the &VIDIOC-REQBUFS; ioctl.</para> <para>Applications set the <structfield>type</structfield> field - of a &v4l2-buffer; to the same buffer type as previously + of a &v4l2-buffer; to the same buffer type as was previously used with &v4l2-format; <structfield>type</structfield> and &v4l2-requestbuffers; <structfield>type</structfield>, and the <structfield>index</structfield> field. Valid index numbers range from zero to the number of buffers allocated with &VIDIOC-REQBUFS; (&v4l2-requestbuffers; <structfield>count</structfield>) minus one. +The <structfield>reserved</structfield> field should to set to 0. After calling <constant>VIDIOC_QUERYBUF</constant> with a pointer to this structure drivers return an error code or fill the rest of the structure.</para> @@ -68,8 +69,8 @@ the structure.</para> <constant>V4L2_BUF_FLAG_MAPPED</constant>, <constant>V4L2_BUF_FLAG_QUEUED</constant> and <constant>V4L2_BUF_FLAG_DONE</constant> flags will be valid. The -<structfield>memory</structfield> field will be set to -<constant>V4L2_MEMORY_MMAP</constant>, the <structfield>m.offset</structfield> +<structfield>memory</structfield> field will be set to the current +I/O method, the <structfield>m.offset</structfield> contains the offset of the buffer from the start of the device memory, the <structfield>length</structfield> field its size. The driver may or may not set the remaining fields and flags, they are meaningless in |