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[media] Remove compatibility layer from multi-planar API documentation

This feature will probably be moved to libv4l2.

Signed-off-by: Pawel Osciak <pawel@osciak.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Pawel Osciak 14 年之前
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共有 2 个文件被更改,包括 18 次插入39 次删除
  1. 8 27
      Documentation/DocBook/v4l/planar-apis.xml
  2. 10 12
      Documentation/DocBook/v4l/vidioc-querycap.xml

+ 8 - 27
Documentation/DocBook/v4l/planar-apis.xml

@@ -2,10 +2,10 @@
   <title>Single- and multi-planar APIs</title>
   <title>Single- and multi-planar APIs</title>
 
 
   <para>Some devices require data for each input or output video frame
   <para>Some devices require data for each input or output video frame
-  to be placed in discontiguous memory buffers. In such cases one
+  to be placed in discontiguous memory buffers. In such cases, one
   video frame has to be addressed using more than one memory address, i.e. one
   video frame has to be addressed using more than one memory address, i.e. one
-  pointer per "plane". A plane is a sub-buffer of current frame. For examples
-  of such formats see <xref linkend="pixfmt" />.</para>
+  pointer per "plane". A plane is a sub-buffer of the current frame. For
+  examples of such formats see <xref linkend="pixfmt" />.</para>
 
 
   <para>Initially, V4L2 API did not support multi-planar buffers and a set of
   <para>Initially, V4L2 API did not support multi-planar buffers and a set of
   extensions has been introduced to handle them. Those extensions constitute
   extensions has been introduced to handle them. Those extensions constitute
@@ -14,8 +14,8 @@
   <para>Some of the V4L2 API calls and structures are interpreted differently,
   <para>Some of the V4L2 API calls and structures are interpreted differently,
   depending on whether single- or multi-planar API is being used. An application
   depending on whether single- or multi-planar API is being used. An application
   can choose whether to use one or the other by passing a corresponding buffer
   can choose whether to use one or the other by passing a corresponding buffer
-  type to its ioctl calls. Multi-planar versions of buffer types are suffixed with
-  an `_MPLANE' string. For a list of available multi-planar buffer types
+  type to its ioctl calls. Multi-planar versions of buffer types are suffixed
+  with an `_MPLANE' string. For a list of available multi-planar buffer types
   see &v4l2-buf-type;.
   see &v4l2-buf-type;.
   </para>
   </para>
 
 
@@ -24,28 +24,9 @@
     <para>Multi-planar API introduces new multi-planar formats. Those formats
     <para>Multi-planar API introduces new multi-planar formats. Those formats
     use a separate set of FourCC codes. It is important to distinguish between
     use a separate set of FourCC codes. It is important to distinguish between
     the multi-planar API and a multi-planar format. Multi-planar API calls can
     the multi-planar API and a multi-planar format. Multi-planar API calls can
-    handle all single-planar formats as well, while the single-planar API cannot
-    handle multi-planar formats. Applications do not have to switch between APIs
-    when handling both single- and multi-planar devices and should use the
-    multi-planar API version for both single- and multi-planar formats.
-    Drivers that do not support multi-planar API can still be handled with it,
-    utilizing a compatibility layer built into standard V4L2 ioctl handling.
-    </para>
-  </section>
-
-  <section>
-    <title>Single and multi-planar API compatibility layer</title>
-    <para>In most cases<footnote><para>The compatibility layer does not cover
-    drivers that do not use video_ioctl2() call.</para></footnote>, applications
-    can use the multi-planar API with older drivers that support
-    only its single-planar version and vice versa. Appropriate conversion is
-    done seamlessly for both applications and drivers in the V4L2 core. The
-    general rule of thumb is: as long as an application uses formats that
-    a driver supports, it can use either API (although use of multi-planar
-    formats is only possible with the multi-planar API). The list of formats
-    supported by a driver can be obtained using the &VIDIOC-ENUM-FMT; call.
-    It is possible, but discouraged, for a driver or an application to support
-    and use both versions of the API.</para>
+    handle all single-planar formats as well (as long as they are passed in
+    multi-planar API structures), while the single-planar API cannot
+    handle multi-planar formats.</para>
   </section>
   </section>
 
 
   <section>
   <section>

+ 10 - 12
Documentation/DocBook/v4l/vidioc-querycap.xml

@@ -142,30 +142,28 @@ this array to zero.</entry>
 	  <row>
 	  <row>
 	    <entry><constant>V4L2_CAP_VIDEO_CAPTURE</constant></entry>
 	    <entry><constant>V4L2_CAP_VIDEO_CAPTURE</constant></entry>
 	    <entry>0x00000001</entry>
 	    <entry>0x00000001</entry>
-	    <entry>The device supports single-planar formats through the <link
-linkend="capture">Video Capture</link> interface. An application can use either
-<link linkend="planar-apis">the single or the multi-planar API</link>.</entry>
+	    <entry>The device supports the single-planar API through the <link
+linkend="capture">Video Capture</link> interface.</entry>
 	  </row>
 	  </row>
 	  <row>
 	  <row>
 	    <entry><constant>V4L2_CAP_VIDEO_CAPTURE_MPLANE</constant></entry>
 	    <entry><constant>V4L2_CAP_VIDEO_CAPTURE_MPLANE</constant></entry>
 	    <entry>0x00001000</entry>
 	    <entry>0x00001000</entry>
-	    <entry>The device supports multi-planar formats through the <link
-linkend="capture">Video Capture</link> interface. An application has to use the
-<link linkend="planar-apis">multi-planar API</link>.</entry>
+	    <entry>The device supports the
+	    <link linkend="planar-apis">multi-planar API</link> through the
+	    <link linkend="capture">Video Capture</link> interface.</entry>
 	  </row>
 	  </row>
 	  <row>
 	  <row>
 	    <entry><constant>V4L2_CAP_VIDEO_OUTPUT</constant></entry>
 	    <entry><constant>V4L2_CAP_VIDEO_OUTPUT</constant></entry>
 	    <entry>0x00000002</entry>
 	    <entry>0x00000002</entry>
-	    <entry>The device supports single-planar formats through the <link
-linkend="output">Video Output</link> interface. An application can use either
-<link linkend="planar-apis">the single or the multi-planar API</link>.</entry>
+	    <entry>The device supports the single-planar API through the <link
+linkend="output">Video Output</link> interface.</entry>
 	  </row>
 	  </row>
 	  <row>
 	  <row>
 	    <entry><constant>V4L2_CAP_VIDEO_OUTPUT_MPLANE</constant></entry>
 	    <entry><constant>V4L2_CAP_VIDEO_OUTPUT_MPLANE</constant></entry>
 	    <entry>0x00002000</entry>
 	    <entry>0x00002000</entry>
-	    <entry>The device supports multi-planar formats through the <link
-linkend="output">Video Output</link> interface. An application has to use the
-<link linkend="planar-apis">multi-planar API</link>.</entry>
+	    <entry>The device supports the
+	    <link linkend="planar-apis">multi-planar API</link> through the
+	    <link linkend="output">Video Output</link> interface.</entry>
 	  </row>
 	  </row>
 	  <row>
 	  <row>
 	    <entry><constant>V4L2_CAP_VIDEO_OVERLAY</constant></entry>
 	    <entry><constant>V4L2_CAP_VIDEO_OVERLAY</constant></entry>