[mirror_ubuntu-artful-kernel.git] / Documentation / DocBook / media / v4l / vidioc-querycap.xml

<refentry id="vidioc-querycap">
  <refmeta>
    <refentrytitle>ioctl VIDIOC_QUERYCAP</refentrytitle>
    &manvol;
  </refmeta>

  <refnamediv>
    <refname>VIDIOC_QUERYCAP</refname>
    <refpurpose>Query device capabilities</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_capability *<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_QUERYCAP</para>
	</listitem>
      </varlistentry>
      <varlistentry>
	<term><parameter>argp</parameter></term>
	<listitem>
	  <para></para>
	</listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Description</title>

    <para>All V4L2 devices support the
<constant>VIDIOC_QUERYCAP</constant> ioctl. It is used to identify
kernel devices compatible with this specification and to obtain
information about driver and hardware capabilities. The ioctl takes a
pointer to a &v4l2-capability; which is filled by the driver. When the
driver is not compatible with this specification the ioctl returns an
&EINVAL;.</para>

    <table pgwide="1" frame="none" id="v4l2-capability">
      <title>struct <structname>v4l2_capability</structname></title>
      <tgroup cols="3">
	&cs-str;
	<tbody valign="top">
	  <row>
	    <entry>__u8</entry>
	    <entry><structfield>driver</structfield>[16]</entry>
	    <entry><para>Name of the driver, a unique NUL-terminated
ASCII string. For example: "bttv". Driver specific applications can
use this information to verify the driver identity. It is also useful
to work around known bugs, or to identify drivers in error reports.</para>
<para>Storing strings in fixed sized arrays is bad
practice but unavoidable here. Drivers and applications should take
precautions to never read or write beyond the end of the array and to
make sure the strings are properly NUL-terminated.</para></entry>
	  </row>
	  <row>
	    <entry>__u8</entry>
	    <entry><structfield>card</structfield>[32]</entry>
	    <entry>Name of the device, a NUL-terminated UTF-8 string.
For example: "Yoyodyne TV/FM". One driver may support different brands
or models of video hardware. This information is intended for users,
for example in a menu of available devices. Since multiple TV cards of
the same brand may be installed which are supported by the same
driver, this name should be combined with the character device file
name (&eg; <filename>/dev/video2</filename>) or the
<structfield>bus_info</structfield> string to avoid
ambiguities.</entry>
	  </row>
	  <row>
	    <entry>__u8</entry>
	    <entry><structfield>bus_info</structfield>[32]</entry>
	    <entry>Location of the device in the system, a
NUL-terminated ASCII string. For example: "PCI:0000:05:06.0". This
information is intended for users, to distinguish multiple
identical devices. If no such information is available the field must
simply count the devices controlled by the driver ("platform:vivi-000").
The bus_info must start with "PCI:" for PCI boards, "PCIe:" for PCI Express boards,
"usb-" for USB devices, "I2C:" for i2c devices, "ISA:" for ISA devices,
"parport" for parallel port devices and "platform:" for platform devices.</entry>
	  </row>
	  <row>
	    <entry>__u32</entry>
	    <entry><structfield>version</structfield></entry>
	    <entry><para>Version number of the driver.</para>
<para>Starting with kernel 3.1, the version reported is provided by the
V4L2 subsystem following the kernel numbering scheme. However, it
may not always return the same version as the kernel if, for example,
a stable or distribution-modified kernel uses the V4L2 stack from a
newer kernel.</para>
<para>The version number is formatted using the
<constant>KERNEL_VERSION()</constant> macro:</para></entry>
	  </row>
	  <row>
	    <entry spanname="hspan"><para>
<programlisting>
#define KERNEL_VERSION(a,b,c) (((a) &lt;&lt; 16) + ((b) &lt;&lt; 8) + (c))

__u32 version = KERNEL_VERSION(0, 8, 1);

printf ("Version: %u.%u.%u\n",
	(version &gt;&gt; 16) &amp; 0xFF,
	(version &gt;&gt; 8) &amp; 0xFF,
	 version &amp; 0xFF);
</programlisting></para></entry>
	  </row>
	  <row>
	    <entry>__u32</entry>
	    <entry><structfield>capabilities</structfield></entry>
	    <entry>Available capabilities of the physical device as a whole, see <xref
		linkend="device-capabilities" />. The same physical device can export
		multiple devices in /dev (e.g. /dev/videoX, /dev/vbiY and /dev/radioZ).
		The <structfield>capabilities</structfield> field should contain a union
		of all capabilities available around the several V4L2 devices exported
		to userspace.
		For all those devices the <structfield>capabilities</structfield> field
		returns the same set of	capabilities. This allows applications to open
		just one of the devices (typically the video device) and discover whether
		video, vbi and/or radio are also supported.
	    </entry>
	  </row>
	  <row>
	    <entry>__u32</entry>
	    <entry><structfield>device_caps</structfield></entry>
	    <entry>Device capabilities of the opened device, see <xref
		linkend="device-capabilities" />. Should contain the available capabilities
		of that specific device node. So, for example, <structfield>device_caps</structfield>
		of a radio device will only contain radio related capabilities and
		no video or vbi capabilities. This field is only set if the <structfield>capabilities</structfield>
		field contains the <constant>V4L2_CAP_DEVICE_CAPS</constant> capability.
		Only the <structfield>capabilities</structfield> field can have the
		<constant>V4L2_CAP_DEVICE_CAPS</constant> capability, <structfield>device_caps</structfield>
		will never set <constant>V4L2_CAP_DEVICE_CAPS</constant>.
	    </entry>
	  </row>
	  <row>
	    <entry>__u32</entry>
	    <entry><structfield>reserved</structfield>[3]</entry>
	    <entry>Reserved for future extensions. Drivers must set
this array to zero.</entry>
	  </row>
	</tbody>
      </tgroup>
    </table>

    <table pgwide="1" frame="none" id="device-capabilities">
      <title>Device Capabilities Flags</title>
      <tgroup cols="3">
	&cs-def;
	<tbody valign="top">
	  <row>
	    <entry><constant>V4L2_CAP_VIDEO_CAPTURE</constant></entry>
	    <entry>0x00000001</entry>
	    <entry>The device supports the single-planar API through the <link
linkend="capture">Video Capture</link> interface.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_VIDEO_CAPTURE_MPLANE</constant></entry>
	    <entry>0x00001000</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>
	    <entry><constant>V4L2_CAP_VIDEO_OUTPUT</constant></entry>
	    <entry>0x00000002</entry>
	    <entry>The device supports the single-planar API through the <link
linkend="output">Video Output</link> interface.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_VIDEO_OUTPUT_MPLANE</constant></entry>
	    <entry>0x00002000</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>
	    <entry><constant>V4L2_CAP_VIDEO_M2M</constant></entry>
	    <entry>0x00004000</entry>
	    <entry>The device supports the single-planar API through the
	    Video Memory-To-Memory interface.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_VIDEO_M2M_MPLANE</constant></entry>
	    <entry>0x00008000</entry>
	    <entry>The device supports the
	    <link linkend="planar-apis">multi-planar API</link> through the
	    Video Memory-To-Memory  interface.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_VIDEO_OVERLAY</constant></entry>
	    <entry>0x00000004</entry>
	    <entry>The device supports the <link
linkend="overlay">Video Overlay</link> interface. A video overlay device
typically stores captured images directly in the video memory of a
graphics card, with hardware clipping and scaling.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_VBI_CAPTURE</constant></entry>
	    <entry>0x00000010</entry>
	    <entry>The device supports the <link linkend="raw-vbi">Raw
VBI Capture</link> interface, providing Teletext and Closed Caption
data.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_VBI_OUTPUT</constant></entry>
	    <entry>0x00000020</entry>
	    <entry>The device supports the <link linkend="raw-vbi">Raw VBI Output</link> interface.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_SLICED_VBI_CAPTURE</constant></entry>
	    <entry>0x00000040</entry>
	    <entry>The device supports the <link linkend="sliced">Sliced VBI Capture</link> interface.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_SLICED_VBI_OUTPUT</constant></entry>
	    <entry>0x00000080</entry>
	    <entry>The device supports the <link linkend="sliced">Sliced VBI Output</link> interface.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_RDS_CAPTURE</constant></entry>
	    <entry>0x00000100</entry>
	    <entry>The device supports the <link linkend="rds">RDS</link> capture interface.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_VIDEO_OUTPUT_OVERLAY</constant></entry>
	    <entry>0x00000200</entry>
	    <entry>The device supports the <link linkend="osd">Video
Output Overlay</link> (OSD) interface. Unlike the <wordasword>Video
Overlay</wordasword> interface, this is a secondary function of video
output devices and overlays an image onto an outgoing video signal.
When the driver sets this flag, it must clear the
<constant>V4L2_CAP_VIDEO_OVERLAY</constant> flag and vice
versa.<footnote><para>The &v4l2-framebuffer; lacks an
&v4l2-buf-type; field, therefore the type of overlay is implied by the
driver capabilities.</para></footnote></entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_HW_FREQ_SEEK</constant></entry>
	    <entry>0x00000400</entry>
	    <entry>The device supports the &VIDIOC-S-HW-FREQ-SEEK; ioctl for
hardware frequency seeking.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_RDS_OUTPUT</constant></entry>
	    <entry>0x00000800</entry>
	    <entry>The device supports the <link linkend="rds">RDS</link> output interface.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_TUNER</constant></entry>
	    <entry>0x00010000</entry>
	    <entry>The device has some sort of tuner to
receive RF-modulated video signals. For more information about
tuner programming see
<xref linkend="tuner" />.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_AUDIO</constant></entry>
	    <entry>0x00020000</entry>
	    <entry>The device has audio inputs or outputs. It may or
may not support audio recording or playback, in PCM or compressed
formats. PCM audio support must be implemented as ALSA or OSS
interface. For more information on audio inputs and outputs see <xref
		linkend="audio" />.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_RADIO</constant></entry>
	    <entry>0x00040000</entry>
	    <entry>This is a radio receiver.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_MODULATOR</constant></entry>
	    <entry>0x00080000</entry>
	    <entry>The device has some sort of modulator to
emit RF-modulated video/audio signals. For more information about
modulator programming see
<xref linkend="tuner" />.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_SDR_CAPTURE</constant></entry>
	    <entry>0x00100000</entry>
	    <entry>The device supports the
<link linkend="sdr">SDR Capture</link> interface.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_EXT_PIX_FORMAT</constant></entry>
	    <entry>0x00200000</entry>
	    <entry>The device supports the &v4l2-pix-format; extended
fields.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_READWRITE</constant></entry>
	    <entry>0x01000000</entry>
	    <entry>The device supports the <link
linkend="rw">read()</link> and/or <link linkend="rw">write()</link>
I/O methods.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_ASYNCIO</constant></entry>
	    <entry>0x02000000</entry>
	    <entry>The device supports the <link
linkend="async">asynchronous</link> I/O methods.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_STREAMING</constant></entry>
	    <entry>0x04000000</entry>
	    <entry>The device supports the <link
linkend="mmap">streaming</link> I/O method.</entry>
	  </row>
	  <row>
	    <entry><constant>V4L2_CAP_DEVICE_CAPS</constant></entry>
	    <entry>0x80000000</entry>
	    <entry>The driver fills the <structfield>device_caps</structfield>
	    field. This capability can only appear in the <structfield>capabilities</structfield>
	    field and never in the <structfield>device_caps</structfield> field.</entry>
	  </row>
	</tbody>
      </tgroup>
    </table>
  </refsect1>

  <refsect1>
    &return-value;
  </refsect1>
</refentry>
Commit	Line	Data
8e080c2e MCC	1	<refentry id="vidioc-querycap">
	2	<refmeta>
	3	<refentrytitle>ioctl VIDIOC_QUERYCAP</refentrytitle>
	4	&manvol;
	5	</refmeta>
	6
	7	<refnamediv>
	8	<refname>VIDIOC_QUERYCAP</refname>
	9	<refpurpose>Query device capabilities</refpurpose>
	10	</refnamediv>
	11
	12	<refsynopsisdiv>
	13	<funcsynopsis>
	14	<funcprototype>
	15	<funcdef>int <function>ioctl</function></funcdef>
	16	<paramdef>int <parameter>fd</parameter></paramdef>
	17	<paramdef>int <parameter>request</parameter></paramdef>
	18	<paramdef>struct v4l2_capability *<parameter>argp</parameter></paramdef>
	19	</funcprototype>
	20	</funcsynopsis>
	21	</refsynopsisdiv>
	22
	23	<refsect1>
	24	<title>Arguments</title>
	25
	26	<variablelist>
	27	<varlistentry>
	28	<term><parameter>fd</parameter></term>
	29	<listitem>
	30	<para>&fd;</para>
	31	</listitem>
	32	</varlistentry>
	33	<varlistentry>
	34	<term><parameter>request</parameter></term>
	35	<listitem>
	36	<para>VIDIOC_QUERYCAP</para>
	37	</listitem>
	38	</varlistentry>
	39	<varlistentry>
	40	<term><parameter>argp</parameter></term>
	41	<listitem>
	42	<para></para>
	43	</listitem>
	44	</varlistentry>
	45	</variablelist>
	46	</refsect1>
	47
	48	<refsect1>
	49	<title>Description</title>
	50
	51	<para>All V4L2 devices support the
	52	<constant>VIDIOC_QUERYCAP</constant> ioctl. It is used to identify
	53	kernel devices compatible with this specification and to obtain
	54	information about driver and hardware capabilities. The ioctl takes a
	55	pointer to a &v4l2-capability; which is filled by the driver. When the
	56	driver is not compatible with this specification the ioctl returns an
	57	&EINVAL;.</para>
	58
	59	<table pgwide="1" frame="none" id="v4l2-capability">
	60	<title>struct <structname>v4l2_capability</structname></title>
	61	<tgroup cols="3">
	62	&cs-str;
	63	<tbody valign="top">
	64	<row>
65	<entry>__u8</entry>
66	<entry><structfield>driver</structfield>[16]</entry>
67	<entry><para>Name of the driver, a unique NUL-terminated
68	ASCII string. For example: "bttv". Driver specific applications can
69	use this information to verify the driver identity. It is also useful
c20eb18c MCC	70	to work around known bugs, or to identify drivers in error reports.</para>
c20eb18c MCC	71	<para>Storing strings in fixed sized arrays is bad
8e080c2e MCC	72	practice but unavoidable here. Drivers and applications should take
	73	precautions to never read or write beyond the end of the array and to
	74	make sure the strings are properly NUL-terminated.</para></entry>
	75	</row>
	76	<row>
	77	<entry>__u8</entry>
	78	<entry><structfield>card</structfield>[32]</entry>
22331a5e	79	<entry>Name of the device, a NUL-terminated UTF-8 string.
8e080c2e MCC	80	For example: "Yoyodyne TV/FM". One driver may support different brands
	81	or models of video hardware. This information is intended for users,
	82	for example in a menu of available devices. Since multiple TV cards of
	83	the same brand may be installed which are supported by the same
	84	driver, this name should be combined with the character device file
	85	name (&eg; <filename>/dev/video2</filename>) or the
	86	<structfield>bus_info</structfield> string to avoid
	87	ambiguities.</entry>
	88	</row>
	89	<row>
	90	<entry>__u8</entry>
	91	<entry><structfield>bus_info</structfield>[32]</entry>
	92	<entry>Location of the device in the system, a
cd56c8dd	93	NUL-terminated ASCII string. For example: "PCI:0000:05:06.0". This
8e080c2e	94	information is intended for users, to distinguish multiple
cd56c8dd HV	95	identical devices. If no such information is available the field must
	96	simply count the devices controlled by the driver ("platform:vivi-000").
	97	The bus_info must start with "PCI:" for PCI boards, "PCIe:" for PCI Express boards,
	98	"usb-" for USB devices, "I2C:" for i2c devices, "ISA:" for ISA devices,
	99	"parport" for parallel port devices and "platform:" for platform devices.</entry>
8e080c2e MCC	100	</row>
	101	<row>
	102	<entry>__u32</entry>
	103	<entry><structfield>version</structfield></entry>
c20eb18c	104	<entry><para>Version number of the driver.</para>
5f853487 HV	105	<para>Starting with kernel 3.1, the version reported is provided by the
	106	V4L2 subsystem following the kernel numbering scheme. However, it
	107	may not always return the same version as the kernel if, for example,
	108	a stable or distribution-modified kernel uses the V4L2 stack from a
c20eb18c MCC	109	newer kernel.</para>
c20eb18c MCC	110	<para>The version number is formatted using the
8e080c2e MCC	111	<constant>KERNEL_VERSION()</constant> macro:</para></entry>
	112	</row>
	113	<row>
	114	<entry spanname="hspan"><para>
	115	<programlisting>
	116	#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
	117
	118	__u32 version = KERNEL_VERSION(0, 8, 1);
	119
	120	printf ("Version: %u.%u.%u\n",
	121	(version >> 16) & 0xFF,
	122	(version >> 8) & 0xFF,
	123	version & 0xFF);
	124	</programlisting></para></entry>
	125	</row>
	126	<row>
	127	<entry>__u32</entry>
	128	<entry><structfield>capabilities</structfield></entry>
583aa3a9 HV	129	<entry>Available capabilities of the physical device as a whole, see <xref
	130	linkend="device-capabilities" />. The same physical device can export
	131	multiple devices in /dev (e.g. /dev/videoX, /dev/vbiY and /dev/radioZ).
	132	The <structfield>capabilities</structfield> field should contain a union
	133	of all capabilities available around the several V4L2 devices exported
	134	to userspace.
	135	For all those devices the <structfield>capabilities</structfield> field
	136	returns the same set of capabilities. This allows applications to open
	137	just one of the devices (typically the video device) and discover whether
	138	video, vbi and/or radio are also supported.
	139	</entry>
8e080c2e MCC	140	</row>
	141	<row>
	142	<entry>__u32</entry>
583aa3a9 HV	143	<entry><structfield>device_caps</structfield></entry>
	144	<entry>Device capabilities of the opened device, see <xref
	145	linkend="device-capabilities" />. Should contain the available capabilities
	146	of that specific device node. So, for example, <structfield>device_caps</structfield>
	147	of a radio device will only contain radio related capabilities and
	148	no video or vbi capabilities. This field is only set if the <structfield>capabilities</structfield>
	149	field contains the <constant>V4L2_CAP_DEVICE_CAPS</constant> capability.
	150	Only the <structfield>capabilities</structfield> field can have the
	151	<constant>V4L2_CAP_DEVICE_CAPS</constant> capability, <structfield>device_caps</structfield>
	152	will never set <constant>V4L2_CAP_DEVICE_CAPS</constant>.
	153	</entry>
	154	</row>
	155	<row>
	156	<entry>__u32</entry>
	157	<entry><structfield>reserved</structfield>[3]</entry>
8e080c2e MCC	158	<entry>Reserved for future extensions. Drivers must set
	159	this array to zero.</entry>
	160	</row>
	161	</tbody>
	162	</tgroup>
	163	</table>
	164
	165	<table pgwide="1" frame="none" id="device-capabilities">
	166	<title>Device Capabilities Flags</title>
	167	<tgroup cols="3">
	168	&cs-def;
	169	<tbody valign="top">
	170	<row>
	171	<entry><constant>V4L2_CAP_VIDEO_CAPTURE</constant></entry>
	172	<entry>0x00000001</entry>
d39155d9 PO	173	<entry>The device supports the single-planar API through the <link
d39155d9 PO	174	linkend="capture">Video Capture</link> interface.</entry>
53b5d574 PO	175	</row>
	176	<row>
	177	<entry><constant>V4L2_CAP_VIDEO_CAPTURE_MPLANE</constant></entry>
	178	<entry>0x00001000</entry>
d39155d9 PO	179	<entry>The device supports the
	180	<link linkend="planar-apis">multi-planar API</link> through the
	181	<link linkend="capture">Video Capture</link> interface.</entry>
8e080c2e MCC	182	</row>
	183	<row>
	184	<entry><constant>V4L2_CAP_VIDEO_OUTPUT</constant></entry>
	185	<entry>0x00000002</entry>
d39155d9 PO	186	<entry>The device supports the single-planar API through the <link
d39155d9 PO	187	linkend="output">Video Output</link> interface.</entry>
53b5d574 PO	188	</row>
	189	<row>
	190	<entry><constant>V4L2_CAP_VIDEO_OUTPUT_MPLANE</constant></entry>
	191	<entry>0x00002000</entry>
d39155d9 PO	192	<entry>The device supports the
	193	<link linkend="planar-apis">multi-planar API</link> through the
	194	<link linkend="output">Video Output</link> interface.</entry>
8e080c2e	195	</row>
f0476a83 SN	196	<row>
	197	<entry><constant>V4L2_CAP_VIDEO_M2M</constant></entry>
	198	<entry>0x00004000</entry>
	199	<entry>The device supports the single-planar API through the
	200	Video Memory-To-Memory interface.</entry>
	201	</row>
	202	<row>
	203	<entry><constant>V4L2_CAP_VIDEO_M2M_MPLANE</constant></entry>
	204	<entry>0x00008000</entry>
	205	<entry>The device supports the
	206	<link linkend="planar-apis">multi-planar API</link> through the
	207	Video Memory-To-Memory interface.</entry>
	208	</row>
8e080c2e MCC	209	<row>
	210	<entry><constant>V4L2_CAP_VIDEO_OVERLAY</constant></entry>
	211	<entry>0x00000004</entry>
	212	<entry>The device supports the <link
	213	linkend="overlay">Video Overlay</link> interface. A video overlay device
	214	typically stores captured images directly in the video memory of a
	215	graphics card, with hardware clipping and scaling.</entry>
	216	</row>
	217	<row>
	218	<entry><constant>V4L2_CAP_VBI_CAPTURE</constant></entry>
	219	<entry>0x00000010</entry>
	220	<entry>The device supports the <link linkend="raw-vbi">Raw
	221	VBI Capture</link> interface, providing Teletext and Closed Caption
	222	data.</entry>
	223	</row>
	224	<row>
	225	<entry><constant>V4L2_CAP_VBI_OUTPUT</constant></entry>
	226	<entry>0x00000020</entry>
	227	<entry>The device supports the <link linkend="raw-vbi">Raw VBI Output</link> interface.</entry>
	228	</row>
	229	<row>
	230	<entry><constant>V4L2_CAP_SLICED_VBI_CAPTURE</constant></entry>
	231	<entry>0x00000040</entry>
	232	<entry>The device supports the <link linkend="sliced">Sliced VBI Capture</link> interface.</entry>
	233	</row>
	234	<row>
	235	<entry><constant>V4L2_CAP_SLICED_VBI_OUTPUT</constant></entry>
	236	<entry>0x00000080</entry>
	237	<entry>The device supports the <link linkend="sliced">Sliced VBI Output</link> interface.</entry>
	238	</row>
	239	<row>
	240	<entry><constant>V4L2_CAP_RDS_CAPTURE</constant></entry>
	241	<entry>0x00000100</entry>
0827d066	242	<entry>The device supports the <link linkend="rds">RDS</link> capture interface.</entry>
8e080c2e MCC	243	</row>
	244	<row>
	245	<entry><constant>V4L2_CAP_VIDEO_OUTPUT_OVERLAY</constant></entry>
	246	<entry>0x00000200</entry>
	247	<entry>The device supports the <link linkend="osd">Video
	248	Output Overlay</link> (OSD) interface. Unlike the <wordasword>Video
	249	Overlay</wordasword> interface, this is a secondary function of video
	250	output devices and overlays an image onto an outgoing video signal.
	251	When the driver sets this flag, it must clear the
	252	<constant>V4L2_CAP_VIDEO_OVERLAY</constant> flag and vice
	253	versa.<footnote><para>The &v4l2-framebuffer; lacks an
	254	&v4l2-buf-type; field, therefore the type of overlay is implied by the
	255	driver capabilities.</para></footnote></entry>
	256	</row>
	257	<row>
	258	<entry><constant>V4L2_CAP_HW_FREQ_SEEK</constant></entry>
	259	<entry>0x00000400</entry>
	260	<entry>The device supports the &VIDIOC-S-HW-FREQ-SEEK; ioctl for
	261	hardware frequency seeking.</entry>
	262	</row>
0827d066 HV	263	<row>
	264	<entry><constant>V4L2_CAP_RDS_OUTPUT</constant></entry>
	265	<entry>0x00000800</entry>
	266	<entry>The device supports the <link linkend="rds">RDS</link> output interface.</entry>
	267	</row>
8e080c2e MCC	268	<row>
	269	<entry><constant>V4L2_CAP_TUNER</constant></entry>
	270	<entry>0x00010000</entry>
	271	<entry>The device has some sort of tuner to
	272	receive RF-modulated video signals. For more information about
	273	tuner programming see
	274	<xref linkend="tuner" />.</entry>
	275	</row>
	276	<row>
	277	<entry><constant>V4L2_CAP_AUDIO</constant></entry>
	278	<entry>0x00020000</entry>
	279	<entry>The device has audio inputs or outputs. It may or
	280	may not support audio recording or playback, in PCM or compressed
	281	formats. PCM audio support must be implemented as ALSA or OSS
	282	interface. For more information on audio inputs and outputs see <xref
	283	linkend="audio" />.</entry>
	284	</row>
	285	<row>
	286	<entry><constant>V4L2_CAP_RADIO</constant></entry>
	287	<entry>0x00040000</entry>
	288	<entry>This is a radio receiver.</entry>
	289	</row>
	290	<row>
	291	<entry><constant>V4L2_CAP_MODULATOR</constant></entry>
	292	<entry>0x00080000</entry>
	293	<entry>The device has some sort of modulator to
	294	emit RF-modulated video/audio signals. For more information about
	295	modulator programming see
	296	<xref linkend="tuner" />.</entry>
559f40fe AP	297	</row>
	298	<row>
	299	<entry><constant>V4L2_CAP_SDR_CAPTURE</constant></entry>
	300	<entry>0x00100000</entry>
	301	<entry>The device supports the
	302	<link linkend="sdr">SDR Capture</link> interface.</entry>
d52e2381 LP	303	</row>
	304	<row>
	305	<entry><constant>V4L2_CAP_EXT_PIX_FORMAT</constant></entry>
	306	<entry>0x00200000</entry>
	307	<entry>The device supports the &v4l2-pix-format; extended
	308	fields.</entry>
8e080c2e MCC	309	</row>
	310	<row>
	311	<entry><constant>V4L2_CAP_READWRITE</constant></entry>
	312	<entry>0x01000000</entry>
	313	<entry>The device supports the <link
	314	linkend="rw">read()</link> and/or <link linkend="rw">write()</link>
	315	I/O methods.</entry>
	316	</row>
	317	<row>
	318	<entry><constant>V4L2_CAP_ASYNCIO</constant></entry>
	319	<entry>0x02000000</entry>
	320	<entry>The device supports the <link
	321	linkend="async">asynchronous</link> I/O methods.</entry>
	322	</row>
	323	<row>
	324	<entry><constant>V4L2_CAP_STREAMING</constant></entry>
	325	<entry>0x04000000</entry>
	326	<entry>The device supports the <link
	327	linkend="mmap">streaming</link> I/O method.</entry>
	328	</row>
583aa3a9 HV	329	<row>
	330	<entry><constant>V4L2_CAP_DEVICE_CAPS</constant></entry>
	331	<entry>0x80000000</entry>
	332	<entry>The driver fills the <structfield>device_caps</structfield>
	333	field. This capability can only appear in the <structfield>capabilities</structfield>
	334	field and never in the <structfield>device_caps</structfield> field.</entry>
	335	</row>
8e080c2e MCC	336	</tbody>
	337	</tgroup>
	338	</table>
	339	</refsect1>
	340
	341	<refsect1>
	342	&return-value;
8e080c2e MCC	343	</refsect1>
8e080c2e MCC	344	</refentry>