diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-21 09:03:10 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2009-09-21 09:03:10 -0700 |
commit | c720f5655df159a630fa0290a0bd67c93e92b0bf (patch) | |
tree | 940d139d0ec1ff5201efddef6cc663166a8a2df3 /Documentation/DocBook/v4l/vidioc-enum-fmt.xml | |
parent | 33e6c1a0de818d3698cdab27c42915661011319d (diff) | |
parent | 84d6ae431f315e8973aac3c3fe1d550fc9240ef3 (diff) |
Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (222 commits)
V4L/DVB (13033): pt1: Don't use a deprecated DMA_BIT_MASK macro
V4L/DVB (13029): radio-si4713: remove #include <linux/version.h>
V4L/DVB (13027): go7007: convert printks to v4l2_info
V4L/DVB (13026): s2250-board: Implement brightness and contrast controls
V4L/DVB (13025): s2250-board: Fix memory leaks
V4L/DVB (13024): go7007: Implement vidioc_g_std and vidioc_querystd
V4L/DVB (13023): go7007: Merge struct gofh and go declarations
V4L/DVB (13022): go7007: Fix mpeg controls
V4L/DVB (13021): go7007: Fix whitespace and line lengths
V4L/DVB (13020): go7007: Updates to Kconfig and Makefile
V4L/DVB (13019): video: initial support for ADV7180
V4L/DVB (13018): kzalloc failure ignored in au8522_probe()
V4L/DVB (13017): gspca: kmalloc failure ignored in sd_start()
V4L/DVB (13016): kmalloc failure ignored in lgdt3304_attach() and s921_attach()
V4L/DVB (13015): kmalloc failure ignored in m920x_firmware_download()
V4L/DVB (13014): Add support for Compro VideoMate E800 (DVB-T part only)
V4L/DVB (13013): FM TX: si4713: Kconfig: Fixed two typos.
V4L/DVB (13012): uvc: introduce missing kfree
V4L/DVB (13011): Change tuner type of BeholdTV cards
V4L/DVB (13009): gspca - stv06xx-hdcs: Reduce exposure range
...
Diffstat (limited to 'Documentation/DocBook/v4l/vidioc-enum-fmt.xml')
-rw-r--r-- | Documentation/DocBook/v4l/vidioc-enum-fmt.xml | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/Documentation/DocBook/v4l/vidioc-enum-fmt.xml b/Documentation/DocBook/v4l/vidioc-enum-fmt.xml new file mode 100644 index 00000000000..960d44615ca --- /dev/null +++ b/Documentation/DocBook/v4l/vidioc-enum-fmt.xml @@ -0,0 +1,164 @@ +<refentry id="vidioc-enum-fmt"> + <refmeta> + <refentrytitle>ioctl VIDIOC_ENUM_FMT</refentrytitle> + &manvol; + </refmeta> + + <refnamediv> + <refname>VIDIOC_ENUM_FMT</refname> + <refpurpose>Enumerate image formats</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcprototype> + <funcdef>int <function>ioctl</function></funcdef> + <paramdef>int <parameter>fd</parameter></paramdef> + <paramdef>int <parameter>request</parameter></paramdef> + <paramdef>struct v4l2_fmtdesc +*<parameter>argp</parameter></paramdef> + </funcprototype> + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Arguments</title> + + <variablelist> + <varlistentry> + <term><parameter>fd</parameter></term> + <listitem> + <para>&fd;</para> + </listitem> + </varlistentry> + <varlistentry> + <term><parameter>request</parameter></term> + <listitem> + <para>VIDIOC_ENUM_FMT</para> + </listitem> + </varlistentry> + <varlistentry> + <term><parameter>argp</parameter></term> + <listitem> + <para></para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Description</title> + + <para>To enumerate image formats applications initialize the +<structfield>type</structfield> and <structfield>index</structfield> +field of &v4l2-fmtdesc; and call the +<constant>VIDIOC_ENUM_FMT</constant> ioctl with a pointer to this +structure. Drivers fill the rest of the structure or return an +&EINVAL;. All formats are enumerable by beginning at index zero and +incrementing by one until <errorcode>EINVAL</errorcode> is +returned.</para> + + <table pgwide="1" frame="none" id="v4l2-fmtdesc"> + <title>struct <structname>v4l2_fmtdesc</structname></title> + <tgroup cols="3"> + &cs-str; + <tbody valign="top"> + <row> + <entry>__u32</entry> + <entry><structfield>index</structfield></entry> + <entry>Number of the format in the enumeration, set by +the application. This is in no way related to the <structfield> +pixelformat</structfield> field.</entry> + </row> + <row> + <entry>&v4l2-buf-type;</entry> + <entry><structfield>type</structfield></entry> + <entry>Type of the data stream, set by the application. +Only these types are valid here: +<constant>V4L2_BUF_TYPE_VIDEO_CAPTURE</constant>, +<constant>V4L2_BUF_TYPE_VIDEO_OUTPUT</constant>, +<constant>V4L2_BUF_TYPE_VIDEO_OVERLAY</constant>, and custom (driver +defined) types with code <constant>V4L2_BUF_TYPE_PRIVATE</constant> +and higher.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>flags</structfield></entry> + <entry>See <xref linkend="fmtdesc-flags" /></entry> + </row> + <row> + <entry>__u8</entry> + <entry><structfield>description</structfield>[32]</entry> + <entry>Description of the format, a NUL-terminated ASCII +string. This information is intended for the user, for example: "YUV +4:2:2".</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>pixelformat</structfield></entry> + <entry>The image format identifier. This is a +four character code as computed by the v4l2_fourcc() +macro:</entry> + </row> + <row> + <entry spanname="hspan"><para><programlisting id="v4l2-fourcc"> +#define v4l2_fourcc(a,b,c,d) (((__u32)(a)<<0)|((__u32)(b)<<8)|((__u32)(c)<<16)|((__u32)(d)<<24)) +</programlisting></para><para>Several image formats are already +defined by this specification in <xref linkend="pixfmt" />. Note these +codes are not the same as those used in the Windows world.</para></entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>reserved</structfield>[4]</entry> + <entry>Reserved for future extensions. Drivers must set +the array to zero.</entry> + </row> + </tbody> + </tgroup> + </table> + + <table pgwide="1" frame="none" id="fmtdesc-flags"> + <title>Image Format Description Flags</title> + <tgroup cols="3"> + &cs-def; + <tbody valign="top"> + <row> + <entry><constant>V4L2_FMT_FLAG_COMPRESSED</constant></entry> + <entry>0x0001</entry> + <entry>This is a compressed format.</entry> + </row> + <row> + <entry><constant>V4L2_FMT_FLAG_EMULATED</constant></entry> + <entry>0x0002</entry> + <entry>This format is not native to the device but emulated +through software (usually libv4l2), where possible try to use a native format +instead for better performance.</entry> + </row> + </tbody> + </tgroup> + </table> + </refsect1> + + <refsect1> + &return-value; + + <variablelist> + <varlistentry> + <term><errorcode>EINVAL</errorcode></term> + <listitem> + <para>The &v4l2-fmtdesc; <structfield>type</structfield> +is not supported or the <structfield>index</structfield> is out of +bounds.</para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> +</refentry> + +<!-- +Local Variables: +mode: sgml +sgml-parent-document: "v4l2.sgml" +indent-tabs-mode: nil +End: +--> |