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Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-g-dv-timings.xml')
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diff --git a/Documentation/DocBook/media/v4l/vidioc-g-dv-timings.xml b/Documentation/DocBook/media/v4l/vidioc-g-dv-timings.xml new file mode 100644 index 00000000..72369707 --- /dev/null +++ b/Documentation/DocBook/media/v4l/vidioc-g-dv-timings.xml @@ -0,0 +1,331 @@ +<refentry id="vidioc-g-dv-timings"> + <refmeta> + <refentrytitle>ioctl VIDIOC_G_DV_TIMINGS, VIDIOC_S_DV_TIMINGS</refentrytitle> + &manvol; + </refmeta> + + <refnamediv> + <refname>VIDIOC_G_DV_TIMINGS</refname> + <refname>VIDIOC_S_DV_TIMINGS</refname> + <refpurpose>Get or set DV timings for input or output</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_dv_timings *<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_G_DV_TIMINGS, VIDIOC_S_DV_TIMINGS</para> + </listitem> + </varlistentry> + <varlistentry> + <term><parameter>argp</parameter></term> + <listitem> + <para></para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Description</title> + <para>To set DV timings for the input or output, applications use the +<constant>VIDIOC_S_DV_TIMINGS</constant> ioctl and to get the current timings, +applications use the <constant>VIDIOC_G_DV_TIMINGS</constant> ioctl. The detailed timing +information is filled in using the structure &v4l2-dv-timings;. These ioctls take +a pointer to the &v4l2-dv-timings; structure as argument. If the ioctl is not supported +or the timing values are not correct, the driver returns &EINVAL;.</para> +<para>The <filename>linux/v4l2-dv-timings.h</filename> header can be used to get the +timings of the formats in the <xref linkend="cea861" /> and <xref linkend="vesadmt" /> +standards. If the current input or output does not support DV timings (e.g. if +&VIDIOC-ENUMINPUT; does not set the <constant>V4L2_IN_CAP_DV_TIMINGS</constant> flag), then +&ENODATA; is returned.</para> + </refsect1> + + <refsect1> + &return-value; + + <variablelist> + <varlistentry> + <term><errorcode>EINVAL</errorcode></term> + <listitem> + <para>This ioctl is not supported, or the +<constant>VIDIOC_S_DV_TIMINGS</constant> parameter was unsuitable.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><errorcode>ENODATA</errorcode></term> + <listitem> + <para>Digital video timings are not supported for this input or output.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><errorcode>EBUSY</errorcode></term> + <listitem> + <para>The device is busy and therefore can not change the timings.</para> + </listitem> + </varlistentry> + </variablelist> + + <table pgwide="1" frame="none" id="v4l2-bt-timings"> + <title>struct <structname>v4l2_bt_timings</structname></title> + <tgroup cols="3"> + &cs-str; + <tbody valign="top"> + <row> + <entry>__u32</entry> + <entry><structfield>width</structfield></entry> + <entry>Width of the active video in pixels.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>height</structfield></entry> + <entry>Height of the active video frame in lines. So for interlaced formats the + height of the active video in each field is <structfield>height</structfield>/2.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>interlaced</structfield></entry> + <entry>Progressive (0) or interlaced (1)</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>polarities</structfield></entry> + <entry>This is a bit mask that defines polarities of sync signals. +bit 0 (V4L2_DV_VSYNC_POS_POL) is for vertical sync polarity and bit 1 (V4L2_DV_HSYNC_POS_POL) is for horizontal sync polarity. If the bit is set +(1) it is positive polarity and if is cleared (0), it is negative polarity.</entry> + </row> + <row> + <entry>__u64</entry> + <entry><structfield>pixelclock</structfield></entry> + <entry>Pixel clock in Hz. Ex. 74.25MHz->74250000</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>hfrontporch</structfield></entry> + <entry>Horizontal front porch in pixels</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>hsync</structfield></entry> + <entry>Horizontal sync length in pixels</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>hbackporch</structfield></entry> + <entry>Horizontal back porch in pixels</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>vfrontporch</structfield></entry> + <entry>Vertical front porch in lines. For interlaced formats this refers to the + odd field (aka field 1).</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>vsync</structfield></entry> + <entry>Vertical sync length in lines. For interlaced formats this refers to the + odd field (aka field 1).</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>vbackporch</structfield></entry> + <entry>Vertical back porch in lines. For interlaced formats this refers to the + odd field (aka field 1).</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>il_vfrontporch</structfield></entry> + <entry>Vertical front porch in lines for the even field (aka field 2) of + interlaced field formats.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>il_vsync</structfield></entry> + <entry>Vertical sync length in lines for the even field (aka field 2) of + interlaced field formats.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>il_vbackporch</structfield></entry> + <entry>Vertical back porch in lines for the even field (aka field 2) of + interlaced field formats.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>standards</structfield></entry> + <entry>The video standard(s) this format belongs to. This will be filled in by + the driver. Applications must set this to 0. See <xref linkend="dv-bt-standards"/> + for a list of standards.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>flags</structfield></entry> + <entry>Several flags giving more information about the format. + See <xref linkend="dv-bt-flags"/> for a description of the flags. + </entry> + </row> + </tbody> + </tgroup> + </table> + + <table pgwide="1" frame="none" id="v4l2-dv-timings"> + <title>struct <structname>v4l2_dv_timings</structname></title> + <tgroup cols="4"> + &cs-str; + <tbody valign="top"> + <row> + <entry>__u32</entry> + <entry><structfield>type</structfield></entry> + <entry></entry> + <entry>Type of DV timings as listed in <xref linkend="dv-timing-types"/>.</entry> + </row> + <row> + <entry>union</entry> + <entry><structfield></structfield></entry> + <entry></entry> + </row> + <row> + <entry></entry> + <entry>&v4l2-bt-timings;</entry> + <entry><structfield>bt</structfield></entry> + <entry>Timings defined by BT.656/1120 specifications</entry> + </row> + <row> + <entry></entry> + <entry>__u32</entry> + <entry><structfield>reserved</structfield>[32]</entry> + <entry></entry> + </row> + </tbody> + </tgroup> + </table> + + <table pgwide="1" frame="none" id="dv-timing-types"> + <title>DV Timing types</title> + <tgroup cols="3"> + &cs-str; + <tbody valign="top"> + <row> + <entry>Timing type</entry> + <entry>value</entry> + <entry>Description</entry> + </row> + <row> + <entry></entry> + <entry></entry> + <entry></entry> + </row> + <row> + <entry>V4L2_DV_BT_656_1120</entry> + <entry>0</entry> + <entry>BT.656/1120 timings</entry> + </row> + </tbody> + </tgroup> + </table> + <table pgwide="1" frame="none" id="dv-bt-standards"> + <title>DV BT Timing standards</title> + <tgroup cols="2"> + &cs-str; + <tbody valign="top"> + <row> + <entry>Timing standard</entry> + <entry>Description</entry> + </row> + <row> + <entry></entry> + <entry></entry> + </row> + <row> + <entry>V4L2_DV_BT_STD_CEA861</entry> + <entry>The timings follow the CEA-861 Digital TV Profile standard</entry> + </row> + <row> + <entry>V4L2_DV_BT_STD_DMT</entry> + <entry>The timings follow the VESA Discrete Monitor Timings standard</entry> + </row> + <row> + <entry>V4L2_DV_BT_STD_CVT</entry> + <entry>The timings follow the VESA Coordinated Video Timings standard</entry> + </row> + <row> + <entry>V4L2_DV_BT_STD_GTF</entry> + <entry>The timings follow the VESA Generalized Timings Formula standard</entry> + </row> + </tbody> + </tgroup> + </table> + <table pgwide="1" frame="none" id="dv-bt-flags"> + <title>DV BT Timing flags</title> + <tgroup cols="2"> + &cs-str; + <tbody valign="top"> + <row> + <entry>Flag</entry> + <entry>Description</entry> + </row> + <row> + <entry></entry> + <entry></entry> + </row> + <row> + <entry>V4L2_DV_FL_REDUCED_BLANKING</entry> + <entry>CVT/GTF specific: the timings use reduced blanking (CVT) or the 'Secondary +GTF' curve (GTF). In both cases the horizontal and/or vertical blanking +intervals are reduced, allowing a higher resolution over the same +bandwidth. This is a read-only flag, applications must not set this. + </entry> + </row> + <row> + <entry>V4L2_DV_FL_CAN_REDUCE_FPS</entry> + <entry>CEA-861 specific: set for CEA-861 formats with a framerate that is a multiple +of six. These formats can be optionally played at 1 / 1.001 speed to +be compatible with 60 Hz based standards such as NTSC and PAL-M that use a framerate of +29.97 frames per second. If the transmitter can't generate such frequencies, then the +flag will also be cleared. This is a read-only flag, applications must not set this. + </entry> + </row> + <row> + <entry>V4L2_DV_FL_REDUCED_FPS</entry> + <entry>CEA-861 specific: only valid for video transmitters, the flag is cleared +by receivers. It is also only valid for formats with the V4L2_DV_FL_CAN_REDUCE_FPS flag +set, for other formats the flag will be cleared by the driver. + +If the application sets this flag, then the pixelclock used to set up the transmitter is +divided by 1.001 to make it compatible with NTSC framerates. If the transmitter +can't generate such frequencies, then the flag will also be cleared. + </entry> + </row> + <row> + <entry>V4L2_DV_FL_HALF_LINE</entry> + <entry>Specific to interlaced formats: if set, then field 1 (aka the odd field) +is really one half-line longer and field 2 (aka the even field) is really one half-line +shorter, so each field has exactly the same number of half-lines. Whether half-lines can be +detected or used depends on the hardware. + </entry> + </row> + </tbody> + </tgroup> + </table> + </refsect1> +</refentry> |