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 | |||
54 | &VIDIOC-REQBUFS; ioctl.</para> | 54 | &VIDIOC-REQBUFS; ioctl.</para> |
55 | 55 | ||
56 | <para>Applications set the <structfield>type</structfield> field | 56 | <para>Applications set the <structfield>type</structfield> field |
57 | of a &v4l2-buffer; to the same buffer type as previously | 57 | of a &v4l2-buffer; to the same buffer type as was previously used with |
58 | &v4l2-format; <structfield>type</structfield> and &v4l2-requestbuffers; | 58 | &v4l2-format; <structfield>type</structfield> and &v4l2-requestbuffers; |
59 | <structfield>type</structfield>, and the <structfield>index</structfield> | 59 | <structfield>type</structfield>, and the <structfield>index</structfield> |
60 | field. Valid index numbers range from zero | 60 | field. Valid index numbers range from zero |
61 | to the number of buffers allocated with &VIDIOC-REQBUFS; | 61 | to the number of buffers allocated with &VIDIOC-REQBUFS; |
62 | (&v4l2-requestbuffers; <structfield>count</structfield>) minus one. | 62 | (&v4l2-requestbuffers; <structfield>count</structfield>) minus one. |
63 | The <structfield>reserved</structfield> field should to set to 0. | ||
63 | After calling <constant>VIDIOC_QUERYBUF</constant> with a pointer to | 64 | After calling <constant>VIDIOC_QUERYBUF</constant> with a pointer to |
64 | this structure drivers return an error code or fill the rest of | 65 | this structure drivers return an error code or fill the rest of |
65 | the structure.</para> | 66 | the structure.</para> |
@@ -68,8 +69,8 @@ the structure.</para> | |||
68 | <constant>V4L2_BUF_FLAG_MAPPED</constant>, | 69 | <constant>V4L2_BUF_FLAG_MAPPED</constant>, |
69 | <constant>V4L2_BUF_FLAG_QUEUED</constant> and | 70 | <constant>V4L2_BUF_FLAG_QUEUED</constant> and |
70 | <constant>V4L2_BUF_FLAG_DONE</constant> flags will be valid. The | 71 | <constant>V4L2_BUF_FLAG_DONE</constant> flags will be valid. The |
71 | <structfield>memory</structfield> field will be set to | 72 | <structfield>memory</structfield> field will be set to the current |
72 | <constant>V4L2_MEMORY_MMAP</constant>, the <structfield>m.offset</structfield> | 73 | I/O method, the <structfield>m.offset</structfield> |
73 | contains the offset of the buffer from the start of the device memory, | 74 | contains the offset of the buffer from the start of the device memory, |
74 | the <structfield>length</structfield> field its size. The driver may | 75 | the <structfield>length</structfield> field its size. The driver may |
75 | or may not set the remaining fields and flags, they are meaningless in | 76 | or may not set the remaining fields and flags, they are meaningless in |