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-rw-r--r--Documentation/DocBook/media/v4l/io.xml10
-rw-r--r--Documentation/DocBook/media/v4l/v4l2.xml10
-rw-r--r--Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml28
3 files changed, 40 insertions, 8 deletions
diff --git a/Documentation/DocBook/media/v4l/io.xml b/Documentation/DocBook/media/v4l/io.xml
index da654031ef3f..144158b3a5ac 100644
--- a/Documentation/DocBook/media/v4l/io.xml
+++ b/Documentation/DocBook/media/v4l/io.xml
@@ -699,7 +699,7 @@ linkend="v4l2-buf-type" /></entry>
buffer. It depends on the negotiated data format and may change with
each buffer for compressed variable size data like JPEG images.
Drivers must set this field when <structfield>type</structfield>
-refers to an input stream, applications when it refers to an output stream.
+refers to a capture stream, applications when it refers to an output stream.
If the application sets this to 0 for an output stream, then
<structfield>bytesused</structfield> will be set to the size of the
buffer (see the <structfield>length</structfield> field of this struct) by
@@ -720,14 +720,14 @@ linkend="buffer-flags" />.</entry>
<entry>Indicates the field order of the image in the
buffer, see <xref linkend="v4l2-field" />. This field is not used when
the buffer contains VBI data. Drivers must set it when
-<structfield>type</structfield> refers to an input stream,
+<structfield>type</structfield> refers to a capture stream,
applications when it refers to an output stream.</entry>
</row>
<row>
<entry>struct timeval</entry>
<entry><structfield>timestamp</structfield></entry>
<entry></entry>
- <entry><para>For input streams this is time when the first data
+ <entry><para>For capture streams this is time when the first data
byte was captured, as returned by the
<function>clock_gettime()</function> function for the relevant
clock id; see <constant>V4L2_BUF_FLAG_TIMESTAMP_*</constant> in
@@ -866,7 +866,7 @@ must set this to 0.</entry>
<entry></entry>
<entry>The number of bytes occupied by data in the plane
(its payload). Drivers must set this field when <structfield>type</structfield>
- refers to an input stream, applications when it refers to an output stream.
+ refers to a capture stream, applications when it refers to an output stream.
If the application sets this to 0 for an output stream, then
<structfield>bytesused</structfield> will be set to the size of the
plane (see the <structfield>length</structfield> field of this struct)
@@ -919,7 +919,7 @@ must set this to 0.</entry>
<entry></entry>
<entry>Offset in bytes to video data in the plane.
Drivers must set this field when <structfield>type</structfield>
- refers to an input stream, applications when it refers to an output stream.
+ refers to a capture stream, applications when it refers to an output stream.
Note that data_offset is included in <structfield>bytesused</structfield>.
So the size of the image in the plane is
<structfield>bytesused</structfield>-<structfield>data_offset</structfield> at
diff --git a/Documentation/DocBook/media/v4l/v4l2.xml b/Documentation/DocBook/media/v4l/v4l2.xml
index 7e61643358de..42e626d6c936 100644
--- a/Documentation/DocBook/media/v4l/v4l2.xml
+++ b/Documentation/DocBook/media/v4l/v4l2.xml
@@ -152,6 +152,16 @@ structs, ioctls) must be noted in more detail in the history chapter
(compat.xml), along with the possible impact on existing drivers and
applications. -->
<revision>
+ <revnumber>4.5</revnumber>
+ <date>2015-10-29</date>
+ <authorinitials>rr</authorinitials>
+ <revremark>Extend vidioc-g-ext-ctrls;. Replace ctrl_class with a new
+union with ctrl_class and which. Which is used to select the current value of
+the control or the default value.
+ </revremark>
+ </revision>
+
+ <revision>
<revnumber>4.4</revnumber>
<date>2015-05-26</date>
<authorinitials>ap</authorinitials>
diff --git a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml
index 842536aae8b4..eb82f7e7d06b 100644
--- a/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml
+++ b/Documentation/DocBook/media/v4l/vidioc-g-ext-ctrls.xml
@@ -61,7 +61,7 @@ must belong to the same control class.</para>
<para>Applications must always fill in the
<structfield>count</structfield>,
-<structfield>ctrl_class</structfield>,
+<structfield>which</structfield>,
<structfield>controls</structfield> and
<structfield>reserved</structfield> fields of &v4l2-ext-controls;, and
initialize the &v4l2-ext-control; array pointed to by the
@@ -109,7 +109,7 @@ the driver whether wrong values are automatically adjusted to a valid
value or if an error is returned.</para>
<para>When the <structfield>id</structfield> or
-<structfield>ctrl_class</structfield> is invalid drivers return an
+<structfield>which</structfield> is invalid drivers return an
&EINVAL;. When the value is out of bounds drivers can choose to take
the closest valid value or return an &ERANGE;, whatever seems more
appropriate. In the first case the new value is set in
@@ -223,7 +223,12 @@ Valid if <constant>V4L2_CTRL_FLAG_HAS_PAYLOAD</constant> is set for this control
<tgroup cols="3">
&cs-str;
<tbody valign="top">
+ <row>
+ <entry>union</entry>
+ <entry>(anonymous)</entry>
+ </row>
<row>
+ <entry></entry>
<entry>__u32</entry>
<entry><structfield>ctrl_class</structfield></entry>
<entry>The control class to which all controls belong, see
@@ -235,6 +240,23 @@ with a <structfield>count</structfield> of 0. If that succeeds, then the driver
supports this feature.</entry>
</row>
<row>
+ <entry></entry>
+ <entry>__u32</entry>
+ <entry><structfield>which</structfield></entry>
+ <entry><para>Which value of the control to get/set/try. <constant>V4L2_CTRL_WHICH_CUR_VAL</constant>
+will return the current value of the control and <constant>V4L2_CTRL_WHICH_DEF_VAL</constant> will
+return the default value of the control. Please note that you can only get the default value of the
+control, you cannot set or try it.</para>
+<para>For backwards compatibility you can also use a control class here (see
+<xref linkend="ctrl-class" />). In that case all controls have to belong to that
+control class. This usage is deprecated, instead just use <constant>V4L2_CTRL_WHICH_CUR_VAL</constant>.
+There are some very old drivers that do not yet support <constant>V4L2_CTRL_WHICH_CUR_VAL</constant>
+and that require a control class here. You can test for such drivers by setting ctrl_class to
+<constant>V4L2_CTRL_WHICH_CUR_VAL</constant> and calling VIDIOC_TRY_EXT_CTRLS with a count of 0.
+If that fails, then the driver does not support <constant>V4L2_CTRL_WHICH_CUR_VAL</constant>.</para>
+</entry>
+ </row>
+ <row>
<entry>__u32</entry>
<entry><structfield>count</structfield></entry>
<entry>The number of controls in the controls array. May
@@ -390,7 +412,7 @@ These controls are described in <xref linkend="rf-tuner-controls" />.</entry>
<listitem>
<para>The &v4l2-ext-control; <structfield>id</structfield>
is invalid, the &v4l2-ext-controls;
-<structfield>ctrl_class</structfield> is invalid, or the &v4l2-ext-control;
+<structfield>which</structfield> is invalid, or the &v4l2-ext-control;
<structfield>value</structfield> was inappropriate (e.g. the given menu
index is not supported by the driver). This error code is
also returned by the <constant>VIDIOC_S_EXT_CTRLS</constant> and