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authorLinus Torvalds <torvalds@linux-foundation.org>2013-06-18 06:25:08 -1000
committerLinus Torvalds <torvalds@linux-foundation.org>2013-06-18 06:25:08 -1000
commitaad760136537fdfa10e5ac76bd3c79bde2100863 (patch)
tree816799b39ccf17d3a3ecfb47578d9bce05259f51 /Documentation
parentf93f0b9cf7c6056ebeb844ed68a8e44888fffa05 (diff)
parentaf44ad5edd1eb6ca92ed5be48e0004e1f04bf219 (diff)
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media fixes from Mauro Carvalho Chehab: "Series of fixes for 3.10. There are some usual driver fixes (mostly on s5p/exynos playform drivers), plus some fixes at V4L2 core" * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (40 commits) [media] soc_camera: error dev remove and v4l2 call [media] sh_veu: fix the buffer size calculation [media] sh_veu: keep power supply until the m2m context is released [media] sh_veu: invoke v4l2_m2m_job_finish() even if a job has been aborted [media] v4l2-ioctl: don't print the clips list [media] v4l2-ctrls: V4L2_CTRL_CLASS_FM_RX controls are also valid radio controls [media] cx88: fix NULL pointer dereference [media] DocBook/media/v4l: update version number [media] exynos4-is: Remove "sysreg" clock handling [media] exynos4-is: Fix reported colorspace at FIMC-IS-ISP subdev [media] exynos4-is: Ensure fimc-is clocks are not enabled until properly configured [media] exynos4-is: Prevent NULL pointer dereference when firmware isn't loaded [media] s5p-mfc: Add NULL check for allocated buffer [media] s5p-mfc: added missing end-of-lines in debug messages [media] s5p-mfc: v4l2 controls setup routine moved to initialization code [media] s5p-mfc: separate encoder parameters for h264 and mpeg4 [media] s5p-mfc: Remove special clock usage in driver [media] s5p-mfc: Remove unused s5p_mfc_get_decoded_status_v6() function [media] v4l2: mem2mem: save irq flags correctly [media] coda: v4l2-compliance fix: add VIDIOC_CREATE_BUFS support ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/DocBook/media/v4l/dev-codec.xml35
-rw-r--r--Documentation/DocBook/media/v4l/v4l2.xml2
-rw-r--r--Documentation/devicetree/bindings/media/exynos-fimc-lite.txt2
3 files changed, 24 insertions, 15 deletions
diff --git a/Documentation/DocBook/media/v4l/dev-codec.xml b/Documentation/DocBook/media/v4l/dev-codec.xml
index dca0ecd54dc..ff44c16fc08 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 bfc93cdcf69..bfe823dd0f3 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;
diff --git a/Documentation/devicetree/bindings/media/exynos-fimc-lite.txt b/Documentation/devicetree/bindings/media/exynos-fimc-lite.txt
index 3f62adfb3e0..de9f6b78ee5 100644
--- a/Documentation/devicetree/bindings/media/exynos-fimc-lite.txt
+++ b/Documentation/devicetree/bindings/media/exynos-fimc-lite.txt
@@ -2,7 +2,7 @@ Exynos4x12/Exynos5 SoC series camera host interface (FIMC-LITE)
Required properties:
-- compatible : should be "samsung,exynos4212-fimc" for Exynos4212 and
+- compatible : should be "samsung,exynos4212-fimc-lite" for Exynos4212 and
Exynos4412 SoCs;
- reg : physical base address and size of the device memory mapped
registers;