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Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-querycap.xml')
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diff --git a/Documentation/DocBook/media/v4l/vidioc-querycap.xml b/Documentation/DocBook/media/v4l/vidioc-querycap.xml deleted file mode 100644 index cd82148..0000000 --- a/Documentation/DocBook/media/v4l/vidioc-querycap.xml +++ /dev/null @@ -1,350 +0,0 @@ -<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 (⪚ <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) << 16) + ((b) << 8) + (c)) - -__u32 version = KERNEL_VERSION(0, 8, 1); - -printf ("Version: %u.%u.%u\n", - (version >> 16) & 0xFF, - (version >> 8) & 0xFF, - version & 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_SDR_OUTPUT</constant></entry> - <entry>0x00400000</entry> - <entry>The device supports the -<link linkend="sdr">SDR Output</link> interface.</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> |
