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authorHans Verkuil <hans.verkuil@cisco.com>2014-07-18 07:58:42 +0200
committerMauro Carvalho Chehab <m.chehab@samsung.com>2014-07-22 05:41:23 +0200
commit12c78e665f96b3f73dc0b6a6190a4871fe526293 (patch)
treebf763f92203365e81ae31abfd0bb919ee96769e3 /Documentation/DocBook
parent[media] videodev2.h: add defines for the VBI field start lines (diff)
downloadlinux-12c78e665f96b3f73dc0b6a6190a4871fe526293.tar.xz
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[media] DocBook media: document new VBI defines
Add defines for the start line numbers of each field for both 525 and 625 line formats. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Diffstat (limited to 'Documentation/DocBook')
-rw-r--r--Documentation/DocBook/media/v4l/dev-raw-vbi.xml12
-rw-r--r--Documentation/DocBook/media/v4l/dev-sliced-vbi.xml9
2 files changed, 17 insertions, 4 deletions
diff --git a/Documentation/DocBook/media/v4l/dev-raw-vbi.xml b/Documentation/DocBook/media/v4l/dev-raw-vbi.xml
index b788c72c885e..f4b61b6ce3c2 100644
--- a/Documentation/DocBook/media/v4l/dev-raw-vbi.xml
+++ b/Documentation/DocBook/media/v4l/dev-raw-vbi.xml
@@ -150,9 +150,15 @@ signal. Drivers shall not convert the sample format by software.</para></entry>
<entry>This is the scanning system line number
associated with the first line of the VBI image, of the first and the
second field respectively. See <xref linkend="vbi-525" /> and
-<xref linkend="vbi-625" /> for valid values. VBI input drivers can
-return start values 0 if the hardware cannot reliable identify
-scanning lines, VBI acquisition may not require this
+<xref linkend="vbi-625" /> for valid values.
+The <constant>V4L2_VBI_ITU_525_F1_START</constant>,
+<constant>V4L2_VBI_ITU_525_F2_START</constant>,
+<constant>V4L2_VBI_ITU_625_F1_START</constant> and
+<constant>V4L2_VBI_ITU_625_F2_START</constant> defines give the start line
+numbers for each field for each 525 or 625 line format as a convenience.
+Don't forget that ITU line numbering starts at 1, not 0.
+VBI input drivers can return start values 0 if the hardware cannot
+reliable identify scanning lines, VBI acquisition may not require this
information.</entry>
</row>
<row>
diff --git a/Documentation/DocBook/media/v4l/dev-sliced-vbi.xml b/Documentation/DocBook/media/v4l/dev-sliced-vbi.xml
index 548f8ea28dee..7a8bf3011ee9 100644
--- a/Documentation/DocBook/media/v4l/dev-sliced-vbi.xml
+++ b/Documentation/DocBook/media/v4l/dev-sliced-vbi.xml
@@ -185,7 +185,14 @@ tables, sigh. --></para></entry>
<entry></entry>
<entry spanname="hspan">Drivers must set
<structfield>service_lines</structfield>[0][0] and
-<structfield>service_lines</structfield>[1][0] to zero.</entry>
+<structfield>service_lines</structfield>[1][0] to zero.
+The <constant>V4L2_VBI_ITU_525_F1_START</constant>,
+<constant>V4L2_VBI_ITU_525_F2_START</constant>,
+<constant>V4L2_VBI_ITU_625_F1_START</constant> and
+<constant>V4L2_VBI_ITU_625_F2_START</constant> defines give the start
+line numbers for each field for each 525 or 625 line format as a
+convenience. Don't forget that ITU line numbering starts at 1, not 0.
+</entry>
</row>
<row>
<entry>__u32</entry>