Merge branch 'linus' into patchwork

* linus: (1465 commits)
  ARM: tegra30: clocks: Fix pciex clock registration
  lseek(fd, n, SEEK_END) does *not* go to eof - n
  Linux 3.10-rc6
  smp.h: Use local_irq_{save,restore}() in !SMP version of on_each_cpu().
  powerpc: Fix missing/delayed calls to irq_work
  powerpc: Fix emulation of illegal instructions on PowerNV platform
  powerpc: Fix stack overflow crash in resume_kernel when ftracing
  snd_pcm_link(): fix a leak...
  use can_lookup() instead of direct checks of ->i_op->lookup
  move exit_task_namespaces() outside of exit_notify()
  fput: task_work_add() can fail if the caller has passed exit_task_work()
  xfs: don't shutdown log recovery on validation errors
  xfs: ensure btree root split sets blkno correctly
  xfs: fix implicit padding in directory and attr CRC formats
  xfs: don't emit v5 superblock warnings on write
  mei: me: clear interrupts on the resume path
  mei: nfc: fix nfc device freeing
  mei: init: Flush scheduled work before resetting the device
  sctp: fully initialize sctp_outq in sctp_outq_init
  netiucv: Hold rtnl between name allocation and device registration.
  ...

2 files changed, 23 insertions, 14 deletions

diff --git a/Documentation/DocBook/media/v4l/dev-codec.xml b/Documentation/DocBook/media/v4l/dev-codec.xml
index dca0ecd54dc6..ff44c16fc080 100644
--- a/Documentation/DocBook/media/v4l/dev-codec.xml
+++ b/Documentation/DocBook/media/v4l/dev-codec.xml
@@ -1,18 +1,27 @@
   <title>Codec Interface</title>
 
-  <note>
-    <title>Suspended</title>
+  <para>A V4L2 codec can compress, decompress, transform, or otherwise
+convert video data from one format into another format, in memory. Typically
+such devices are memory-to-memory devices (i.e. devices with the
+<constant>V4L2_CAP_VIDEO_M2M</constant> or <constant>V4L2_CAP_VIDEO_M2M_MPLANE</constant>
+capability set).
+</para>
 
-    <para>This interface has been be suspended from the V4L2 API
-implemented in Linux 2.6 until we have more experience with codec
-device interfaces.</para>
-  </note>
+  <para>A memory-to-memory video node acts just like a normal video node, but it
+supports both output (sending frames from memory to the codec hardware) and
+capture (receiving the processed frames from the codec hardware into memory)
+stream I/O. An application will have to setup the stream
+I/O for both sides and finally call &VIDIOC-STREAMON; for both capture and output
+to start the codec.</para>
 
-  <para>A V4L2 codec can compress, decompress, transform, or otherwise
-convert video data from one format into another format, in memory.
-Applications send data to be converted to the driver through a
-&func-write; call, and receive the converted data through a
-&func-read; call. For efficiency a driver may also support streaming
-I/O.</para>
+  <para>Video compression codecs use the MPEG controls to setup their codec parameters
+(note that the MPEG controls actually support many more codecs than just MPEG).
+See <xref linkend="mpeg-controls"></xref>.</para>
 
-  <para>[to do]</para>
+  <para>Memory-to-memory devices can often be used as a shared resource: you can
+open the video node multiple times, each application setting up their own codec properties
+that are local to the file handle, and each can use it independently from the others.
+The driver will arbitrate access to the codec and reprogram it whenever another file
+handler gets access. This is different from the usual video node behavior where the video properties
+are global to the device (i.e. changing something through one file handle is visible
+through another file handle).</para>
diff --git a/Documentation/DocBook/media/v4l/v4l2.xml b/Documentation/DocBook/media/v4l/v4l2.xml
index bfc93cdcf696..bfe823dd0f31 100644
--- a/Documentation/DocBook/media/v4l/v4l2.xml
+++ b/Documentation/DocBook/media/v4l/v4l2.xml
@@ -493,7 +493,7 @@ and discussions on the V4L mailing list.</revremark>
 </partinfo>
 
 <title>Video for Linux Two API Specification</title>
- <subtitle>Revision 3.9</subtitle>
+ <subtitle>Revision 3.10</subtitle>
 
   <chapter id="common">
     &sub-common;