summaryrefslogtreecommitdiff
path: root/Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml
diff options
context:
space:
mode:
authorHans Verkuil <hans.verkuil@cisco.com>2014-03-07 18:17:33 +0400
committerMauro Carvalho Chehab <m.chehab@samsung.com>2014-03-11 17:13:58 +0400
commite25436581f4117a0df9bf5539f6a7702a78df317 (patch)
tree3e06304a9ba175ad5f181f7da0ae45453aee3116 /Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml
parentb09dfac83201812bf359e32a17afc7f6763ae379 (diff)
downloadlinux-e25436581f4117a0df9bf5539f6a7702a78df317.tar.xz
[media] DocBook v4l2: update the G/S_EDID documentation
Document that it is now possible to call G/S_EDID from video nodes, not just sub-device nodes. Add a note that -EINVAL will be returned if the pad does not support EDIDs. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml')
-rw-r--r--Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml152
1 files changed, 0 insertions, 152 deletions
diff --git a/Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml b/Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml
deleted file mode 100644
index bbd18f0e6ede..000000000000
--- a/Documentation/DocBook/media/v4l/vidioc-subdev-g-edid.xml
+++ /dev/null
@@ -1,152 +0,0 @@
-<refentry id="vidioc-subdev-g-edid">
- <refmeta>
- <refentrytitle>ioctl VIDIOC_SUBDEV_G_EDID, VIDIOC_SUBDEV_S_EDID</refentrytitle>
- &manvol;
- </refmeta>
-
- <refnamediv>
- <refname>VIDIOC_SUBDEV_G_EDID</refname>
- <refname>VIDIOC_SUBDEV_S_EDID</refname>
- <refpurpose>Get or set the EDID of a video receiver/transmitter</refpurpose>
- </refnamediv>
-
- <refsynopsisdiv>
- <funcsynopsis>
- <funcprototype>
- <funcdef>int <function>ioctl</function></funcdef>
- <paramdef>int <parameter>fd</parameter></paramdef>
- <paramdef>int <parameter>request</parameter></paramdef>
- <paramdef>struct v4l2_subdev_edid *<parameter>argp</parameter></paramdef>
- </funcprototype>
- </funcsynopsis>
- <funcsynopsis>
- <funcprototype>
- <funcdef>int <function>ioctl</function></funcdef>
- <paramdef>int <parameter>fd</parameter></paramdef>
- <paramdef>int <parameter>request</parameter></paramdef>
- <paramdef>const struct v4l2_subdev_edid *<parameter>argp</parameter></paramdef>
- </funcprototype>
- </funcsynopsis>
- </refsynopsisdiv>
-
- <refsect1>
- <title>Arguments</title>
-
- <variablelist>
- <varlistentry>
- <term><parameter>fd</parameter></term>
- <listitem>
- <para>&fd;</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>request</parameter></term>
- <listitem>
- <para>VIDIOC_SUBDEV_G_EDID, VIDIOC_SUBDEV_S_EDID</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>argp</parameter></term>
- <listitem>
- <para></para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
-
- <refsect1>
- <title>Description</title>
- <para>These ioctls can be used to get or set an EDID associated with an input pad
- from a receiver or an output pad of a transmitter subdevice.</para>
-
- <para>To get the EDID data the application has to fill in the <structfield>pad</structfield>,
- <structfield>start_block</structfield>, <structfield>blocks</structfield> and <structfield>edid</structfield>
- fields and call <constant>VIDIOC_SUBDEV_G_EDID</constant>. The current EDID from block
- <structfield>start_block</structfield> and of size <structfield>blocks</structfield>
- will be placed in the memory <structfield>edid</structfield> points to. The <structfield>edid</structfield>
- pointer must point to memory at least <structfield>blocks</structfield>&nbsp;*&nbsp;128 bytes
- large (the size of one block is 128 bytes).</para>
-
- <para>If there are fewer blocks than specified, then the driver will set <structfield>blocks</structfield>
- to the actual number of blocks. If there are no EDID blocks available at all, then the error code
- ENODATA is set.</para>
-
- <para>If blocks have to be retrieved from the sink, then this call will block until they
- have been read.</para>
-
- <para>To set the EDID blocks of a receiver the application has to fill in the <structfield>pad</structfield>,
- <structfield>blocks</structfield> and <structfield>edid</structfield> fields and set
- <structfield>start_block</structfield> to 0. It is not possible to set part of an EDID,
- it is always all or nothing. Setting the EDID data is only valid for receivers as it makes
- no sense for a transmitter.</para>
-
- <para>The driver assumes that the full EDID is passed in. If there are more EDID blocks than
- the hardware can handle then the EDID is not written, but instead the error code E2BIG is set
- and <structfield>blocks</structfield> is set to the maximum that the hardware supports.
- If <structfield>start_block</structfield> is any
- value other than 0 then the error code EINVAL is set.</para>
-
- <para>To disable an EDID you set <structfield>blocks</structfield> to 0. Depending on the
- hardware this will drive the hotplug pin low and/or block the source from reading the EDID
- data in some way. In any case, the end result is the same: the EDID is no longer available.
- </para>
-
- <table pgwide="1" frame="none" id="v4l2-subdev-edid">
- <title>struct <structname>v4l2_subdev_edid</structname></title>
- <tgroup cols="3">
- &cs-str;
- <tbody valign="top">
- <row>
- <entry>__u32</entry>
- <entry><structfield>pad</structfield></entry>
- <entry>Pad for which to get/set the EDID blocks.</entry>
- </row>
- <row>
- <entry>__u32</entry>
- <entry><structfield>start_block</structfield></entry>
- <entry>Read the EDID from starting with this block. Must be 0 when setting
- the EDID.</entry>
- </row>
- <row>
- <entry>__u32</entry>
- <entry><structfield>blocks</structfield></entry>
- <entry>The number of blocks to get or set. Must be less or equal to 256 (the
- maximum number of blocks as defined by the standard). When you set the EDID and
- <structfield>blocks</structfield> is 0, then the EDID is disabled or erased.</entry>
- </row>
- <row>
- <entry>__u8&nbsp;*</entry>
- <entry><structfield>edid</structfield></entry>
- <entry>Pointer to memory that contains the EDID. The minimum size is
- <structfield>blocks</structfield>&nbsp;*&nbsp;128.</entry>
- </row>
- <row>
- <entry>__u32</entry>
- <entry><structfield>reserved</structfield>[5]</entry>
- <entry>Reserved for future extensions. Applications and drivers must
- set the array to zero.</entry>
- </row>
- </tbody>
- </tgroup>
- </table>
- </refsect1>
-
- <refsect1>
- &return-value;
-
- <variablelist>
- <varlistentry>
- <term><errorcode>ENODATA</errorcode></term>
- <listitem>
- <para>The EDID data is not available.</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><errorcode>E2BIG</errorcode></term>
- <listitem>
- <para>The EDID data you provided is more than the hardware can handle.</para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
-</refentry>