Documentation/DocBook/media/v4l/vidioc-g-tuner.xml

   1 <refentry id="vidioc-g-tuner">
   2   <refmeta>
   3     <refentrytitle>ioctl VIDIOC_G_TUNER, VIDIOC_S_TUNER</refentrytitle>
   4     &manvol;
   5   </refmeta>
   6
   7   <refnamediv>
   8     <refname>VIDIOC_G_TUNER</refname>
   9     <refname>VIDIOC_S_TUNER</refname>
  10     <refpurpose>Get or set tuner attributes</refpurpose>
  11   </refnamediv>
  12
  13   <refsynopsisdiv>
  14     <funcsynopsis>
  15       <funcprototype>
  16         <funcdef>int <function>ioctl</function></funcdef>
  17         <paramdef>int <parameter>fd</parameter></paramdef>
  18         <paramdef>int <parameter>request</parameter></paramdef>
  19         <paramdef>struct v4l2_tuner
  20 *<parameter>argp</parameter></paramdef>
  21       </funcprototype>
  22     </funcsynopsis>
  23     <funcsynopsis>
  24       <funcprototype>
  25         <funcdef>int <function>ioctl</function></funcdef>
  26         <paramdef>int <parameter>fd</parameter></paramdef>
  27         <paramdef>int <parameter>request</parameter></paramdef>
  28         <paramdef>const struct v4l2_tuner
  29 *<parameter>argp</parameter></paramdef>
  30       </funcprototype>
  31     </funcsynopsis>
  32   </refsynopsisdiv>
  33
  34   <refsect1>
  35     <title>Arguments</title>
  36
  37     <variablelist>
  38       <varlistentry>
  39         <term><parameter>fd</parameter></term>
  40         <listitem>
  41           <para>&fd;</para>
  42         </listitem>
  43       </varlistentry>
  44       <varlistentry>
  45         <term><parameter>request</parameter></term>
  46         <listitem>
  47           <para>VIDIOC_G_TUNER, VIDIOC_S_TUNER</para>
  48         </listitem>
  49       </varlistentry>
  50       <varlistentry>
  51         <term><parameter>argp</parameter></term>
  52         <listitem>
  53           <para></para>
  54         </listitem>
  55       </varlistentry>
  56     </variablelist>
  57   </refsect1>
  58
  59   <refsect1>
  60     <title>Description</title>
  61
  62     <para>To query the attributes of a tuner applications initialize the
  63 <structfield>index</structfield> field and zero out the
  64 <structfield>reserved</structfield> array of a &v4l2-tuner; and call the
  65 <constant>VIDIOC_G_TUNER</constant> ioctl with a pointer to this
  66 structure. Drivers fill the rest of the structure or return an
  67 &EINVAL; when the index is out of bounds. To enumerate all tuners
  68 applications shall begin at index zero, incrementing by one until the
  69 driver returns <errorcode>EINVAL</errorcode>.</para>
  70
  71     <para>Tuners have two writable properties, the audio mode and
  72 the radio frequency. To change the audio mode, applications initialize
  73 the <structfield>index</structfield>,
  74 <structfield>audmode</structfield> and
  75 <structfield>reserved</structfield> fields and call the
  76 <constant>VIDIOC_S_TUNER</constant> ioctl. This will
  77 <emphasis>not</emphasis> change the current tuner, which is determined
  78 by the current video input. Drivers may choose a different audio mode
  79 if the requested mode is invalid or unsupported. Since this is a
  80 <!-- FIXME -->write-only ioctl, it does not return the actually
  81 selected audio mode.</para>
  82
  83     <para><link linkend="sdr">SDR</link> specific tuner types are
  84 <constant>V4L2_TUNER_SDR</constant> and <constant>V4L2_TUNER_RF</constant>.
  85 For SDR devices <structfield>audmode</structfield> field must be
  86 initialized to zero.
  87 The term 'tuner' means SDR receiver in this context.</para>
  88
  89     <para>To change the radio frequency the &VIDIOC-S-FREQUENCY; ioctl
  90 is available.</para>
  91
  92     <table pgwide="1" frame="none" id="v4l2-tuner">
  93       <title>struct <structname>v4l2_tuner</structname></title>
  94       <tgroup cols="3">
  95         <colspec colname="c1" colwidth="1*" />
  96         <colspec colname="c2" colwidth="1*" />
  97         <colspec colname="c3" colwidth="1*" />
  98         <colspec colname="c4" colwidth="1*" />
  99         <spanspec spanname="hspan" namest="c3" nameend="c4" />
 100         <tbody valign="top">
 101           <row>
 102             <entry>__u32</entry>
 103             <entry><structfield>index</structfield></entry>
 104             <entry spanname="hspan">Identifies the tuner, set by the
 105 application.</entry>
 106           </row>
 107           <row>
 108             <entry>__u8</entry>
 109             <entry><structfield>name</structfield>[32]</entry>
 110             <entry spanname="hspan"><para>Name of the tuner, a
 111 NUL-terminated ASCII string. This information is intended for the
 112 user.<!-- FIXME Video inputs already have a name, the purpose of this
 113 field is not quite clear.--></para></entry>
 114           </row>
 115           <row>
 116             <entry>__u32</entry>
 117             <entry><structfield>type</structfield></entry>
 118             <entry spanname="hspan">Type of the tuner, see <xref
 119                 linkend="v4l2-tuner-type" />.</entry>
 120           </row>
 121           <row>
 122             <entry>__u32</entry>
 123             <entry><structfield>capability</structfield></entry>
 124             <entry spanname="hspan"><para>Tuner capability flags, see
 125 <xref linkend="tuner-capability" />. Audio flags indicate the ability
 126 to decode audio subprograms. They will <emphasis>not</emphasis>
 127 change, for example with the current video standard.</para><para>When
 128 the structure refers to a radio tuner the
 129 <constant>V4L2_TUNER_CAP_LANG1</constant>,
 130 <constant>V4L2_TUNER_CAP_LANG2</constant> and
 131 <constant>V4L2_TUNER_CAP_NORM</constant> flags can't be used.</para>
 132 <para>If multiple frequency bands are supported, then
 133 <structfield>capability</structfield> is the union of all
 134 <structfield>capability</structfield> fields of each &v4l2-frequency-band;.
 135 </para></entry>
 136           </row>
 137           <row>
 138             <entry>__u32</entry>
 139             <entry><structfield>rangelow</structfield></entry>
 140             <entry spanname="hspan">The lowest tunable frequency in
 141 units of 62.5 kHz, or if the <structfield>capability</structfield>
 142 flag <constant>V4L2_TUNER_CAP_LOW</constant> is set, in units of 62.5
 143 Hz, or if the <structfield>capability</structfield> flag
 144 <constant>V4L2_TUNER_CAP_1HZ</constant> is set, in units of 1 Hz.
 145 If multiple frequency bands are supported, then
 146 <structfield>rangelow</structfield> is the lowest frequency
 147 of all the frequency bands.</entry>
 148           </row>
 149           <row>
 150             <entry>__u32</entry>
 151             <entry><structfield>rangehigh</structfield></entry>
 152             <entry spanname="hspan">The highest tunable frequency in
 153 units of 62.5 kHz, or if the <structfield>capability</structfield>
 154 flag <constant>V4L2_TUNER_CAP_LOW</constant> is set, in units of 62.5
 155 Hz, or if the <structfield>capability</structfield> flag
 156 <constant>V4L2_TUNER_CAP_1HZ</constant> is set, in units of 1 Hz.
 157 If multiple frequency bands are supported, then
 158 <structfield>rangehigh</structfield> is the highest frequency
 159 of all the frequency bands.</entry>
 160           </row>
 161           <row>
 162             <entry>__u32</entry>
 163             <entry><structfield>rxsubchans</structfield></entry>
 164             <entry spanname="hspan"><para>Some tuners or audio
 165 decoders can determine the received audio subprograms by analyzing
 166 audio carriers, pilot tones or other indicators. To pass this
 167 information drivers set flags defined in <xref
 168                   linkend="tuner-rxsubchans" /> in this field. For
 169 example:</para></entry>
 170           </row>
 171           <row>
 172             <entry></entry>
 173             <entry></entry>
 174             <entry><constant>V4L2_TUNER_SUB_MONO</constant></entry>
 175             <entry>receiving mono audio</entry>
 176           </row>
 177           <row>
 178             <entry></entry>
 179             <entry></entry>
 180             <entry><constant>STEREO | SAP</constant></entry>
 181             <entry>receiving stereo audio and a secondary audio
 182 program</entry>
 183           </row>
 184           <row>
 185             <entry></entry>
 186             <entry></entry>
 187             <entry><constant>MONO | STEREO</constant></entry>
 188             <entry>receiving mono or stereo audio, the hardware cannot
 189 distinguish</entry>
 190           </row>
 191           <row>
 192             <entry></entry>
 193             <entry></entry>
 194             <entry><constant>LANG1 | LANG2</constant></entry>
 195             <entry>receiving bilingual audio</entry>
 196           </row>
 197           <row>
 198             <entry></entry>
 199             <entry></entry>
 200             <entry><constant>MONO | STEREO | LANG1 | LANG2</constant></entry>
 201             <entry>receiving mono, stereo or bilingual
 202 audio</entry>
 203           </row>
 204           <row>
 205             <entry></entry>
 206             <entry></entry>
 207             <entry spanname="hspan"><para>When the
 208 <constant>V4L2_TUNER_CAP_STEREO</constant>,
 209 <constant>_LANG1</constant>, <constant>_LANG2</constant> or
 210 <constant>_SAP</constant> flag is cleared in the
 211 <structfield>capability</structfield> field, the corresponding
 212 <constant>V4L2_TUNER_SUB_</constant> flag must not be set
 213 here.</para><para>This field is valid only if this is the tuner of the
 214 current video input, or when the structure refers to a radio
 215 tuner.</para></entry>
 216           </row>
 217           <row>
 218             <entry>__u32</entry>
 219             <entry><structfield>audmode</structfield></entry>
 220             <entry spanname="hspan"><para>The selected audio mode, see
 221 <xref linkend="tuner-audmode" /> for valid values. The audio mode does
 222 not affect audio subprogram detection, and like a <link
 223 linkend="control">control</link> it does not automatically change
 224 unless the requested mode is invalid or unsupported. See <xref
 225                   linkend="tuner-matrix" /> for possible results when
 226 the selected and received audio programs do not
 227 match.</para><para>Currently this is the only field of struct
 228 <structname>v4l2_tuner</structname> applications can
 229 change.</para></entry>
 230           </row>
 231           <row>
 232             <entry>__u32</entry>
 233             <entry><structfield>signal</structfield></entry>
 234             <entry spanname="hspan">The signal strength if known, ranging
 235 from 0 to 65535. Higher values indicate a better signal.</entry>
 236           </row>
 237           <row>
 238             <entry>__s32</entry>
 239             <entry><structfield>afc</structfield></entry>
 240             <entry spanname="hspan">Automatic frequency control: When the
 241 <structfield>afc</structfield> value is negative, the frequency is too
 242 low, when positive too high.<!-- FIXME need example what to do when it never
 243 settles at zero, &ie; range is what? --></entry>
 244           </row>
 245           <row>
 246             <entry>__u32</entry>
 247             <entry><structfield>reserved</structfield>[4]</entry>
 248             <entry spanname="hspan">Reserved for future extensions. Drivers and
 249 applications must set the array to zero.</entry>
 250           </row>
 251         </tbody>
 252       </tgroup>
 253     </table>
 254
 255     <table pgwide="1" frame="none" id="v4l2-tuner-type">
 256       <title>enum v4l2_tuner_type</title>
 257       <tgroup cols="3">
 258         &cs-def;
 259         <tbody valign="top">
 260           <row>
 261             <entry><constant>V4L2_TUNER_RADIO</constant></entry>
 262             <entry>1</entry>
 263             <entry></entry>
 264           </row>
 265           <row>
 266             <entry><constant>V4L2_TUNER_ANALOG_TV</constant></entry>
 267             <entry>2</entry>
 268             <entry></entry>
 269           </row>
 270           <row>
 271             <entry><constant>V4L2_TUNER_SDR</constant></entry>
 272             <entry>4</entry>
 273             <entry></entry>
 274           </row>
 275           <row>
 276             <entry><constant>V4L2_TUNER_RF</constant></entry>
 277             <entry>5</entry>
 278             <entry></entry>
 279           </row>
 280         </tbody>
 281       </tgroup>
 282     </table>
 283
 284     <table pgwide="1" frame="none" id="tuner-capability">
 285       <title>Tuner and Modulator Capability Flags</title>
 286       <tgroup cols="3">
 287         &cs-def;
 288         <tbody valign="top">
 289           <row>
 290             <entry><constant>V4L2_TUNER_CAP_LOW</constant></entry>
 291             <entry>0x0001</entry>
 292             <entry>When set, tuning frequencies are expressed in units of
 293 62.5 Hz instead of 62.5 kHz.</entry>
 294           </row>
 295           <row>
 296             <entry><constant>V4L2_TUNER_CAP_NORM</constant></entry>
 297             <entry>0x0002</entry>
 298             <entry>This is a multi-standard tuner; the video standard
 299 can or must be switched. (B/G PAL tuners for example are typically not
 300       considered multi-standard because the video standard is automatically
 301       determined from the frequency band.) The set of supported video
 302       standards is available from the &v4l2-input; pointing to this tuner,
 303       see the description of ioctl &VIDIOC-ENUMINPUT; for details. Only
 304       <constant>V4L2_TUNER_ANALOG_TV</constant> tuners can have this capability.</entry>
 305           </row>
 306           <row>
 307             <entry><constant>V4L2_TUNER_CAP_HWSEEK_BOUNDED</constant></entry>
 308             <entry>0x0004</entry>
 309             <entry>If set, then this tuner supports the hardware seek functionality
 310             where the seek stops when it reaches the end of the frequency range.</entry>
 311           </row>
 312           <row>
 313             <entry><constant>V4L2_TUNER_CAP_HWSEEK_WRAP</constant></entry>
 314             <entry>0x0008</entry>
 315             <entry>If set, then this tuner supports the hardware seek functionality
 316             where the seek wraps around when it reaches the end of the frequency range.</entry>
 317           </row>
 318           <row>
 319         <entry><constant>V4L2_TUNER_CAP_STEREO</constant></entry>
 320         <entry>0x0010</entry>
 321         <entry>Stereo audio reception is supported.</entry>
 322           </row>
 323           <row>
 324             <entry><constant>V4L2_TUNER_CAP_LANG1</constant></entry>
 325             <entry>0x0040</entry>
 326             <entry>Reception of the primary language of a bilingual
 327 audio program is supported. Bilingual audio is a feature of
 328 two-channel systems, transmitting the primary language monaural on the
 329 main audio carrier and a secondary language monaural on a second
 330 carrier. Only
 331       <constant>V4L2_TUNER_ANALOG_TV</constant> tuners can have this capability.</entry>
 332           </row>
 333           <row>
 334             <entry><constant>V4L2_TUNER_CAP_LANG2</constant></entry>
 335             <entry>0x0020</entry>
 336             <entry>Reception of the secondary language of a bilingual
 337 audio program is supported. Only
 338       <constant>V4L2_TUNER_ANALOG_TV</constant> tuners can have this capability.</entry>
 339           </row>
 340           <row>
 341             <entry><constant>V4L2_TUNER_CAP_SAP</constant></entry>
 342             <entry>0x0020</entry>
 343             <entry><para>Reception of a secondary audio program is
 344 supported. This is a feature of the BTSC system which accompanies the
 345 NTSC video standard. Two audio carriers are available for mono or
 346 stereo transmissions of a primary language, and an independent third
 347 carrier for a monaural secondary language. Only
 348       <constant>V4L2_TUNER_ANALOG_TV</constant> tuners can have this capability.</para><para>Note the
 349 <constant>V4L2_TUNER_CAP_LANG2</constant> and
 350 <constant>V4L2_TUNER_CAP_SAP</constant> flags are synonyms.
 351 <constant>V4L2_TUNER_CAP_SAP</constant> applies when the tuner
 352 supports the <constant>V4L2_STD_NTSC_M</constant> video
 353 standard.</para><!-- FIXME what if PAL+NTSC and Bi but not SAP? --></entry>
 354           </row>
 355           <row>
 356         <entry><constant>V4L2_TUNER_CAP_RDS</constant></entry>
 357         <entry>0x0080</entry>
 358         <entry>RDS capture is supported. This capability is only valid for
 359 radio tuners.</entry>
 360           </row>
 361           <row>
 362         <entry><constant>V4L2_TUNER_CAP_RDS_BLOCK_IO</constant></entry>
 363         <entry>0x0100</entry>
 364         <entry>The RDS data is passed as unparsed RDS blocks.</entry>
 365           </row>
 366           <row>
 367         <entry><constant>V4L2_TUNER_CAP_RDS_CONTROLS</constant></entry>
 368         <entry>0x0200</entry>
 369         <entry>The RDS data is parsed by the hardware and set via controls.</entry>
 370           </row>
 371           <row>
 372         <entry><constant>V4L2_TUNER_CAP_FREQ_BANDS</constant></entry>
 373         <entry>0x0400</entry>
 374         <entry>The &VIDIOC-ENUM-FREQ-BANDS; ioctl can be used to enumerate
 375         the available frequency bands.</entry>
 376           </row>
 377           <row>
 378         <entry><constant>V4L2_TUNER_CAP_HWSEEK_PROG_LIM</constant></entry>
 379         <entry>0x0800</entry>
 380         <entry>The range to search when using the hardware seek functionality
 381         is programmable, see &VIDIOC-S-HW-FREQ-SEEK; for details.</entry>
 382           </row>
 383           <row>
 384         <entry><constant>V4L2_TUNER_CAP_1HZ</constant></entry>
 385         <entry>0x1000</entry>
 386         <entry>When set, tuning frequencies are expressed in units of 1 Hz instead of 62.5 kHz.</entry>
 387           </row>
 388         </tbody>
 389       </tgroup>
 390     </table>
 391
 392     <table pgwide="1" frame="none" id="tuner-rxsubchans">
 393       <title>Tuner Audio Reception Flags</title>
 394       <tgroup cols="3">
 395         &cs-def;
 396         <tbody valign="top">
 397           <row>
 398             <entry><constant>V4L2_TUNER_SUB_MONO</constant></entry>
 399             <entry>0x0001</entry>
 400             <entry>The tuner receives a mono audio signal.</entry>
 401           </row>
 402           <row>
 403             <entry><constant>V4L2_TUNER_SUB_STEREO</constant></entry>
 404             <entry>0x0002</entry>
 405             <entry>The tuner receives a stereo audio signal.</entry>
 406           </row>
 407           <row>
 408             <entry><constant>V4L2_TUNER_SUB_LANG1</constant></entry>
 409             <entry>0x0008</entry>
 410             <entry>The tuner receives the primary language of a
 411 bilingual audio signal. Drivers must clear this flag when the current
 412 video standard is <constant>V4L2_STD_NTSC_M</constant>.</entry>
 413           </row>
 414           <row>
 415             <entry><constant>V4L2_TUNER_SUB_LANG2</constant></entry>
 416             <entry>0x0004</entry>
 417             <entry>The tuner receives the secondary language of a
 418 bilingual audio signal (or a second audio program).</entry>
 419           </row>
 420           <row>
 421             <entry><constant>V4L2_TUNER_SUB_SAP</constant></entry>
 422             <entry>0x0004</entry>
 423             <entry>The tuner receives a Second Audio Program. Note the
 424 <constant>V4L2_TUNER_SUB_LANG2</constant> and
 425 <constant>V4L2_TUNER_SUB_SAP</constant> flags are synonyms. The
 426 <constant>V4L2_TUNER_SUB_SAP</constant> flag applies when the
 427 current video standard is <constant>V4L2_STD_NTSC_M</constant>.</entry>
 428           </row>
 429           <row>
 430             <entry><constant>V4L2_TUNER_SUB_RDS</constant></entry>
 431             <entry>0x0010</entry>
 432             <entry>The tuner receives an RDS channel.</entry>
 433           </row>
 434         </tbody>
 435       </tgroup>
 436     </table>
 437
 438     <table pgwide="1" frame="none" id="tuner-audmode">
 439       <title>Tuner Audio Modes</title>
 440       <tgroup cols="3">
 441         &cs-def;
 442         <tbody valign="top">
 443           <row>
 444             <entry><constant>V4L2_TUNER_MODE_MONO</constant></entry>
 445             <entry>0</entry>
 446             <entry>Play mono audio. When the tuner receives a stereo
 447 signal this a down-mix of the left and right channel. When the tuner
 448 receives a bilingual or SAP signal this mode selects the primary
 449 language.</entry>
 450           </row>
 451           <row>
 452             <entry><constant>V4L2_TUNER_MODE_STEREO</constant></entry>
 453             <entry>1</entry>
 454             <entry><para>Play stereo audio. When the tuner receives
 455 bilingual audio it may play different languages on the left and right
 456 channel or the primary language is played on both channels.</para><para>Playing
 457 different languages in this mode is
 458 deprecated. New drivers should do this only in
 459 <constant>MODE_LANG1_LANG2</constant>.</para><para>When the tuner
 460 receives no stereo signal or does not support stereo reception the
 461 driver shall fall back to <constant>MODE_MONO</constant>.</para></entry>
 462           </row>
 463           <row>
 464             <entry><constant>V4L2_TUNER_MODE_LANG1</constant></entry>
 465             <entry>3</entry>
 466             <entry>Play the primary language, mono or stereo. Only
 467 <constant>V4L2_TUNER_ANALOG_TV</constant> tuners support this
 468 mode.</entry>
 469           </row>
 470           <row>
 471             <entry><constant>V4L2_TUNER_MODE_LANG2</constant></entry>
 472             <entry>2</entry>
 473             <entry>Play the secondary language, mono. When the tuner
 474 receives no bilingual audio or SAP, or their reception is not
 475 supported the driver shall fall back to mono or stereo mode. Only
 476 <constant>V4L2_TUNER_ANALOG_TV</constant> tuners support this
 477 mode.</entry>
 478           </row>
 479           <row>
 480             <entry><constant>V4L2_TUNER_MODE_SAP</constant></entry>
 481             <entry>2</entry>
 482             <entry>Play the Second Audio Program. When the tuner
 483 receives no bilingual audio or SAP, or their reception is not
 484 supported the driver shall fall back to mono or stereo mode. Only
 485 <constant>V4L2_TUNER_ANALOG_TV</constant> tuners support this mode.
 486 Note the <constant>V4L2_TUNER_MODE_LANG2</constant> and
 487 <constant>V4L2_TUNER_MODE_SAP</constant> are synonyms.</entry>
 488           </row>
 489           <row>
 490             <entry><constant>V4L2_TUNER_MODE_LANG1_LANG2</constant></entry>
 491             <entry>4</entry>
 492             <entry>Play the primary language on the left channel, the
 493 secondary language on the right channel. When the tuner receives no
 494 bilingual audio or SAP, it shall fall back to
 495 <constant>MODE_LANG1</constant> or <constant>MODE_MONO</constant>.
 496 Only <constant>V4L2_TUNER_ANALOG_TV</constant> tuners support this
 497 mode.</entry>
 498           </row>
 499         </tbody>
 500       </tgroup>
 501     </table>
 502
 503     <table pgwide="1" frame="all" id="tuner-matrix">
 504       <title>Tuner Audio Matrix</title>
 505       <tgroup cols="6" align="center">
 506         <colspec align="left" />
 507         <colspec colname="c2" colwidth="1*" />
 508         <colspec colwidth="1*" />
 509         <colspec colwidth="1*" />
 510         <colspec colnum="6" colname="c6" colwidth="1*" />
 511         <spanspec namest="c2" nameend="c6" spanname="hspan" align="center" />
 512         <thead>
 513           <row>
 514             <entry></entry>
 515             <entry spanname="hspan">Selected
 516 <constant>V4L2_TUNER_MODE_</constant></entry>
 517           </row>
 518           <row>
 519             <entry>Received <constant>V4L2_TUNER_SUB_</constant></entry>
 520             <entry><constant>MONO</constant></entry>
 521             <entry><constant>STEREO</constant></entry>
 522             <entry><constant>LANG1</constant></entry>
 523             <entry><constant>LANG2 = SAP</constant></entry>
 524             <entry><constant>LANG1_LANG2</constant><footnote><para>This
 525 mode has been added in Linux 2.6.17 and may not be supported by older
 526 drivers.</para></footnote></entry>
 527           </row>
 528         </thead>
 529         <tbody valign="top">
 530           <row>
 531             <entry><constant>MONO</constant></entry>
 532             <entry>Mono</entry>
 533             <entry>Mono/Mono</entry>
 534             <entry>Mono</entry>
 535             <entry>Mono</entry>
 536             <entry>Mono/Mono</entry>
 537           </row>
 538           <row>
 539             <entry><constant>MONO | SAP</constant></entry>
 540             <entry>Mono</entry>
 541             <entry>Mono/Mono</entry>
 542             <entry>Mono</entry>
 543             <entry>SAP</entry>
 544             <entry>Mono/SAP (preferred) or Mono/Mono</entry>
 545           </row>
 546           <row>
 547             <entry><constant>STEREO</constant></entry>
 548             <entry>L+R</entry>
 549             <entry>L/R</entry>
 550             <entry>Stereo L/R (preferred) or Mono L+R</entry>
 551             <entry>Stereo L/R (preferred) or Mono L+R</entry>
 552             <entry>L/R (preferred) or L+R/L+R</entry>
 553           </row>
 554           <row>
 555             <entry><constant>STEREO | SAP</constant></entry>
 556             <entry>L+R</entry>
 557             <entry>L/R</entry>
 558             <entry>Stereo L/R (preferred) or Mono L+R</entry>
 559             <entry>SAP</entry>
 560             <entry>L+R/SAP (preferred) or L/R or L+R/L+R</entry>
 561           </row>
 562           <row>
 563             <entry><constant>LANG1 | LANG2</constant></entry>
 564             <entry>Language&nbsp;1</entry>
 565             <entry>Lang1/Lang2 (deprecated<footnote><para>Playback of
 566 both languages in <constant>MODE_STEREO</constant> is deprecated. In
 567 the future drivers should produce only the primary language in this
 568 mode. Applications should request
 569 <constant>MODE_LANG1_LANG2</constant> to record both languages or a
 570 stereo signal.</para></footnote>) or
 571 Lang1/Lang1</entry>
 572             <entry>Language&nbsp;1</entry>
 573             <entry>Language&nbsp;2</entry>
 574             <entry>Lang1/Lang2 (preferred) or Lang1/Lang1</entry>
 575           </row>
 576         </tbody>
 577       </tgroup>
 578     </table>
 579   </refsect1>
 580
 581   <refsect1>
 582     &return-value;
 583
 584     <variablelist>
 585       <varlistentry>
 586         <term><errorcode>EINVAL</errorcode></term>
 587         <listitem>
 588           <para>The &v4l2-tuner; <structfield>index</structfield> is
 589 out of bounds.</para>
 590         </listitem>
 591       </varlistentry>
 592     </variablelist>
 593   </refsect1>
 594 </refentry>