This patch adds description and usage examples for exporting
DMABUF file descriptor in V4L2.
Signed-off-by: Tomasz Stanislawski t.stanisl...@samsung.com
Signed-off-by: Kyungmin Park kyungmin.p...@samsung.com
CC: linux-...@vger.kernel.org
---
Documentation/DocBook/media/v4l/compat.xml|3 +
Documentation/DocBook/media/v4l/io.xml|3 +
Documentation/DocBook/media/v4l/v4l2.xml |1 +
Documentation/DocBook/media/v4l/vidioc-expbuf.xml | 212 +
4 files changed, 219 insertions(+)
create mode 100644 Documentation/DocBook/media/v4l/vidioc-expbuf.xml
diff --git a/Documentation/DocBook/media/v4l/compat.xml
b/Documentation/DocBook/media/v4l/compat.xml
index 50eb630..3dd9e78 100644
--- a/Documentation/DocBook/media/v4l/compat.xml
+++ b/Documentation/DocBook/media/v4l/compat.xml
@@ -2590,6 +2590,9 @@ ioctls./para
paraImporting DMABUF file descriptors as a new IO method described
in xref linkend=dmabuf /./para
/listitem
+listitem
+ paraExporting DMABUF files using VIDIOC-EXPBUF; ioctl./para
+/listitem
/itemizedlist
/section
diff --git a/Documentation/DocBook/media/v4l/io.xml
b/Documentation/DocBook/media/v4l/io.xml
index 0abb5cb..81d0ed4 100644
--- a/Documentation/DocBook/media/v4l/io.xml
+++ b/Documentation/DocBook/media/v4l/io.xml
@@ -488,6 +488,9 @@ DMA buffer from userspace using a file descriptor
previously exported for a
different or the same device (known as the importer role), or both. This
section describes the DMABUF importer role API in V4L2./para
+paraRefer to link linked=vidioc-expbuf DMABUF exporting /link for
+details about exporting V4L2 buffers as DMABUF file descriptors./para
+
paraInput and output devices support the streaming I/O method when the
constantV4L2_CAP_STREAMING/constant flag in the
structfieldcapabilities/structfield field of v4l2-capability; returned by
diff --git a/Documentation/DocBook/media/v4l/v4l2.xml
b/Documentation/DocBook/media/v4l/v4l2.xml
index 10ccde9..4d110b1 100644
--- a/Documentation/DocBook/media/v4l/v4l2.xml
+++ b/Documentation/DocBook/media/v4l/v4l2.xml
@@ -543,6 +543,7 @@ and discussions on the V4L mailing list./revremark
sub-enuminput;
sub-enumoutput;
sub-enumstd;
+sub-expbuf;
sub-g-audio;
sub-g-audioout;
sub-g-crop;
diff --git a/Documentation/DocBook/media/v4l/vidioc-expbuf.xml
b/Documentation/DocBook/media/v4l/vidioc-expbuf.xml
new file mode 100644
index 000..72dfbd2
--- /dev/null
+++ b/Documentation/DocBook/media/v4l/vidioc-expbuf.xml
@@ -0,0 +1,212 @@
+refentry id=vidioc-expbuf
+
+ refmeta
+refentrytitleioctl VIDIOC_EXPBUF/refentrytitle
+manvol;
+ /refmeta
+
+ refnamediv
+refnameVIDIOC_EXPBUF/refname
+refpurposeExport a buffer as a DMABUF file descriptor./refpurpose
+ /refnamediv
+
+ refsynopsisdiv
+funcsynopsis
+ funcprototype
+ funcdefint functionioctl/function/funcdef
+ paramdefint parameterfd/parameter/paramdef
+ paramdefint parameterrequest/parameter/paramdef
+ paramdefstruct v4l2_exportbuffer
*parameterargp/parameter/paramdef
+ /funcprototype
+/funcsynopsis
+ /refsynopsisdiv
+
+ refsect1
+titleArguments/title
+
+variablelist
+ varlistentry
+ termparameterfd/parameter/term
+ listitem
+ parafd;/para
+ /listitem
+ /varlistentry
+ varlistentry
+ termparameterrequest/parameter/term
+ listitem
+ paraVIDIOC_EXPBUF/para
+ /listitem
+ /varlistentry
+ varlistentry
+ termparameterargp/parameter/term
+ listitem
+ para/para
+ /listitem
+ /varlistentry
+/variablelist
+ /refsect1
+
+ refsect1
+titleDescription/title
+
+note
+ titleExperimental/title
+ paraThis is an link linkend=experimental experimental /link
+ interface and may change in the future./para
+/note
+
+paraThis ioctl is an extension to the link linkend=mmapmemory
+mapping/link I/O method, therefore it is available only for
+constantV4L2_MEMORY_MMAP/constant buffers. It can be used to export a
+buffer as a DMABUF file at any time after buffers have been allocated with the
+VIDIOC-REQBUFS; ioctl./para
+
+para To export a buffer, applications fill v4l2-exportbuffer;. The
+structfield type /structfield field is set to the same buffer type as was
+previously used with v4l2-requestbuffers;structfield type /structfield.
+Applications must also set the structfield index /structfield field. Valid
+index numbers range from zero to the number of buffers allocated with
+VIDIOC-REQBUFS; (v4l2-requestbuffers;structfield count /structfield)
+minus one. For the multi-planar API, applications set the structfield plane
+/structfield field to the index of the plane to be exported. Valid planes
+range from zero to the maximal number of valid planes for the currently active
+format. For the single-planar API, applications must set
