diff options
Diffstat (limited to 'Documentation/DocBook/v4l')
| -rw-r--r-- | Documentation/DocBook/v4l/compat.xml | 24 | ||||
| -rw-r--r-- | Documentation/DocBook/v4l/dev-teletext.xml | 29 | ||||
| -rw-r--r-- | Documentation/DocBook/v4l/v4l2.xml | 10 |
3 files changed, 38 insertions, 25 deletions
diff --git a/Documentation/DocBook/v4l/compat.xml b/Documentation/DocBook/v4l/compat.xml index 54447f0d0784..c9ce61d981f5 100644 --- a/Documentation/DocBook/v4l/compat.xml +++ b/Documentation/DocBook/v4l/compat.xml @@ -21,11 +21,15 @@ API.</para> <title>Opening and Closing Devices</title> <para>For compatibility reasons the character device file names -recommended for V4L2 video capture, overlay, radio, teletext and raw +recommended for V4L2 video capture, overlay, radio and raw vbi capture devices did not change from those used by V4L. They are listed in <xref linkend="devices" /> and below in <xref linkend="v4l-dev" />.</para> + <para>The teletext devices (minor range 192-223) have been removed in +V4L2 and no longer exist. There is no hardware available anymore for handling +pure teletext. Instead raw or sliced VBI is used.</para> + <para>The V4L <filename>videodev</filename> module automatically assigns minor numbers to drivers in load order, depending on the registered device type. We recommend that V4L2 drivers by default @@ -66,13 +70,6 @@ not compatible with V4L or V4L2.</para> </footnote>, <entry>64-127</entry> </row> <row> - <entry>Teletext decoder</entry> - <entry><para><filename>/dev/vtx</filename>, -<filename>/dev/vtx0</filename> to -<filename>/dev/vtx31</filename></para></entry> - <entry>192-223</entry> - </row> - <row> <entry>Raw VBI capture</entry> <entry><para><filename>/dev/vbi</filename>, <filename>/dev/vbi0</filename> to @@ -2345,6 +2342,17 @@ more information.</para> </listitem> </orderedlist> </section> + <section> + <title>V4L2 in Linux 2.6.37</title> + <orderedlist> + <listitem> + <para>Remove the vtx (videotext/teletext) API. This API was no longer +used and no hardware exists to verify the API. Nor were any userspace applications found +that used it. It was originally scheduled for removal in 2.6.35. + </para> + </listitem> + </orderedlist> + </section> <section id="other"> <title>Relation of V4L2 to other Linux multimedia APIs</title> diff --git a/Documentation/DocBook/v4l/dev-teletext.xml b/Documentation/DocBook/v4l/dev-teletext.xml index 76184e8ed618..414b1cfff9f4 100644 --- a/Documentation/DocBook/v4l/dev-teletext.xml +++ b/Documentation/DocBook/v4l/dev-teletext.xml @@ -1,35 +1,32 @@ <title>Teletext Interface</title> - <para>This interface aims at devices receiving and demodulating + <para>This interface was aimed at devices receiving and demodulating Teletext data [<xref linkend="ets300706" />, <xref linkend="itu653" />], evaluating the Teletext packages and storing formatted pages in cache memory. Such devices are usually implemented as microcontrollers with serial -interface (I<superscript>2</superscript>C) and can be found on older +interface (I<superscript>2</superscript>C) and could be found on old TV cards, dedicated Teletext decoding cards and home-brew devices connected to the PC parallel port.</para> - <para>The Teletext API was designed by Martin Buck. It is defined in + <para>The Teletext API was designed by Martin Buck. It was defined in the kernel header file <filename>linux/videotext.h</filename>, the specification is available from <ulink url="ftp://ftp.gwdg.de/pub/linux/misc/videotext/"> ftp://ftp.gwdg.de/pub/linux/misc/videotext/</ulink>. (Videotext is the name of -the German public television Teletext service.) Conventional character -device file names are <filename>/dev/vtx</filename> and -<filename>/dev/vttuner</filename>, with device number 83, 0 and 83, 16 -respectively. A similar interface exists for the Philips SAA5249 -Teletext decoder [specification?] with character device file names -<filename>/dev/tlkN</filename>, device number 102, N.</para> +the German public television Teletext service.)</para> <para>Eventually the Teletext API was integrated into the V4L API with character device file names <filename>/dev/vtx0</filename> to <filename>/dev/vtx31</filename>, device major number 81, minor numbers -192 to 223. For reference the V4L Teletext API specification is -reproduced here in full: "Teletext interfaces talk the existing VTX -API." Teletext devices with major number 83 and 102 will be removed in -Linux 2.6.</para> +192 to 223.</para> - <para>There are no plans to replace the Teletext API or to integrate -it into V4L2. Please write to the linux-media mailing list: &v4l-ml; -when the need arises.</para> + <para>However, teletext decoders were quickly replaced by more +generic VBI demodulators and those dedicated teletext decoders no longer exist. +For many years the vtx devices were still around, even though nobody used +them. So the decision was made to finally remove support for the Teletext API in +kernel 2.6.37.</para> + + <para>Modern devices all use the <link linkend="raw-vbi">raw</link> or +<link linkend="sliced">sliced</link> VBI API.</para> <!-- Local Variables: diff --git a/Documentation/DocBook/v4l/v4l2.xml b/Documentation/DocBook/v4l/v4l2.xml index 7c3c098d5d08..839e93e875ae 100644 --- a/Documentation/DocBook/v4l/v4l2.xml +++ b/Documentation/DocBook/v4l/v4l2.xml @@ -99,6 +99,7 @@ Remote Controller chapter.</contrib> <year>2007</year> <year>2008</year> <year>2009</year> + <year>2010</year> <holder>Bill Dirks, Michael H. Schimek, Hans Verkuil, Martin Rubli, Andy Walls, Muralidharan Karicheri, Mauro Carvalho Chehab</holder> </copyright> @@ -110,10 +111,17 @@ Rubli, Andy Walls, Muralidharan Karicheri, Mauro Carvalho Chehab</holder> <!-- Put document revisions here, newest first. --> <!-- API revisions (changes and additions of defines, enums, structs, ioctls) must be noted in more detail in the history chapter -(compat.sgml), along with the possible impact on existing drivers and +(compat.xml), along with the possible impact on existing drivers and applications. --> <revision> + <revnumber>2.6.37</revnumber> + <date>2010-08-06</date> + <authorinitials>hv</authorinitials> + <revremark>Removed obsolete vtx (videotext) API.</revremark> + </revision> + + <revision> <revnumber>2.6.33</revnumber> <date>2009-12-03</date> <authorinitials>mk</authorinitials> |