1 <title>DVB Frontend API</title>
3 <para>The DVB frontend device controls the tuner and DVB demodulator
4 hardware. It can be accessed through <emphasis
5 role="tt">/dev/dvb/adapter0/frontend0</emphasis>. Data types and and
6 ioctl definitions can be accessed by including <emphasis
7 role="tt">linux/dvb/frontend.h</emphasis> in your application.</para>
9 <para>DVB frontends come in three varieties: DVB-S (satellite), DVB-C
10 (cable) and DVB-T (terrestrial). Transmission via the internet (DVB-IP)
11 is not yet handled by this API but a future extension is possible. For
12 DVB-S the frontend device also supports satellite equipment control
13 (SEC) via DiSEqC and V-SEC protocols. The DiSEqC (digital SEC)
14 specification is available from
15 <ulink url="http://www.eutelsat.com/satellites/4_5_5.html">Eutelsat</ulink>.</para>
17 <para>Note that the DVB API may also be used for MPEG decoder-only PCI
18 cards, in which case there exists no frontend device.</para>
20 <section id="frontend_types">
21 <title>Frontend Data Types</title>
23 <section id="fe-type-t">
24 <title>Frontend type</title>
26 <para>For historical reasons, frontend types are named by the type of modulation used in
27 transmission. The fontend types are given by fe_type_t type, defined as:</para>
29 <table pgwide="1" frame="none" id="fe-type">
30 <title>Frontend types</title>
35 <entry>fe_type</entry>
36 <entry>Description</entry>
37 <entry><link linkend="DTV-DELIVERY-SYSTEM">DTV_DELIVERY_SYSTEM</link> equivalent type</entry>
42 <entry id="FE_QPSK"><constant>FE_QPSK</constant></entry>
43 <entry>For DVB-S standard</entry>
44 <entry><constant>SYS_DVBS</constant></entry>
47 <entry id="FE_QAM"><constant>FE_QAM</constant></entry>
48 <entry>For DVB-C annex A standard</entry>
49 <entry><constant>SYS_DVBC_ANNEX_A</constant></entry>
52 <entry id="FE_OFDM"><constant>FE_OFDM</constant></entry>
53 <entry>For DVB-T standard</entry>
54 <entry><constant>SYS_DVBT</constant></entry>
57 <entry id="FE_ATSC"><constant>FE_ATSC</constant></entry>
58 <entry>For ATSC standard (terrestrial) or for DVB-C Annex B (cable) used in US.</entry>
59 <entry><constant>SYS_ATSC</constant> (terrestrial) or <constant>SYS_DVBC_ANNEX_B</constant> (cable)</entry>
61 </tbody></tgroup></table>
63 <para>Newer formats like DVB-S2, ISDB-T, ISDB-S and DVB-T2 are not described at the above, as they're
64 supported via the new <link linkend="FE_GET_SET_PROPERTY">FE_GET_PROPERTY/FE_GET_SET_PROPERTY</link> ioctl's, using the <link linkend="DTV-DELIVERY-SYSTEM">DTV_DELIVERY_SYSTEM</link> parameter.
67 <para>The usage of this field is deprecated, as it doesn't report all supported standards, and
68 will provide an incomplete information for frontends that support multiple delivery systems.
69 Please use <link linkend="DTV-ENUM-DELSYS">DTV_ENUM_DELSYS</link> instead.</para>
72 <section id="fe-caps-t">
73 <title>frontend capabilities</title>
75 <para>Capabilities describe what a frontend can do. Some capabilities can only be supported for
76 a specific frontend type.</para>
78 typedef enum fe_caps {
80 FE_CAN_INVERSION_AUTO = 0x1,
84 FE_CAN_FEC_4_5 = 0x10,
85 FE_CAN_FEC_5_6 = 0x20,
86 FE_CAN_FEC_6_7 = 0x40,
87 FE_CAN_FEC_7_8 = 0x80,
88 FE_CAN_FEC_8_9 = 0x100,
89 FE_CAN_FEC_AUTO = 0x200,
91 FE_CAN_QAM_16 = 0x800,
92 FE_CAN_QAM_32 = 0x1000,
93 FE_CAN_QAM_64 = 0x2000,
94 FE_CAN_QAM_128 = 0x4000,
95 FE_CAN_QAM_256 = 0x8000,
96 FE_CAN_QAM_AUTO = 0x10000,
97 FE_CAN_TRANSMISSION_MODE_AUTO = 0x20000,
98 FE_CAN_BANDWIDTH_AUTO = 0x40000,
99 FE_CAN_GUARD_INTERVAL_AUTO = 0x80000,
100 FE_CAN_HIERARCHY_AUTO = 0x100000,
101 FE_CAN_8VSB = 0x200000,
102 FE_CAN_16VSB = 0x400000,
103 FE_HAS_EXTENDED_CAPS = 0x800000,
104 FE_CAN_MULTISTREAM = 0x4000000,
105 FE_CAN_TURBO_FEC = 0x8000000,
106 FE_CAN_2G_MODULATION = 0x10000000,
107 FE_NEEDS_BENDING = 0x20000000,
108 FE_CAN_RECOVER = 0x40000000,
109 FE_CAN_MUTE_TS = 0x80000000
114 <section id="dvb-frontend-info">
115 <title>frontend information</title>
117 <para>Information about the frontend ca be queried with
118 <link linkend="FE_GET_INFO">FE_GET_INFO</link>.</para>
121 struct dvb_frontend_info {
124 uint32_t frequency_min;
125 uint32_t frequency_max;
126 uint32_t frequency_stepsize;
127 uint32_t frequency_tolerance;
128 uint32_t symbol_rate_min;
129 uint32_t symbol_rate_max;
130 uint32_t symbol_rate_tolerance; /⋆ ppm ⋆/
131 uint32_t notifier_delay; /⋆ ms ⋆/
137 <section id="dvb-diseqc-master-cmd">
138 <title>diseqc master command</title>
140 <para>A message sent from the frontend to DiSEqC capable equipment.</para>
142 struct dvb_diseqc_master_cmd {
143 uint8_t msg [6]; /⋆ { framing, address, command, data[3] } ⋆/
144 uint8_t msg_len; /⋆ valid values are 3...6 ⋆/
148 <section role="subsection" id="dvb-diseqc-slave-reply">
149 <title>diseqc slave reply</title>
151 <para>A reply to the frontend from DiSEqC 2.0 capable equipment.</para>
153 struct dvb_diseqc_slave_reply {
154 uint8_t msg [4]; /⋆ { framing, data [3] } ⋆/
155 uint8_t msg_len; /⋆ valid values are 0...4, 0 means no msg ⋆/
156 int timeout; /⋆ return from ioctl after timeout ms with ⋆/
157 }; /⋆ errorcode when no message was received ⋆/
161 <section id="fe-sec-voltage-t">
162 <title>diseqc slave reply</title>
163 <para>The voltage is usually used with non-DiSEqC capable LNBs to switch the polarzation
164 (horizontal/vertical). When using DiSEqC epuipment this voltage has to be switched
165 consistently to the DiSEqC commands as described in the DiSEqC spec.</para>
167 typedef enum fe_sec_voltage {
174 <section id="fe-sec-tone-mode-t">
175 <title>SEC continuous tone</title>
177 <para>The continuous 22KHz tone is usually used with non-DiSEqC capable LNBs to switch the
178 high/low band of a dual-band LNB. When using DiSEqC epuipment this voltage has to
179 be switched consistently to the DiSEqC commands as described in the DiSEqC
182 typedef enum fe_sec_tone_mode {
185 } fe_sec_tone_mode_t;
189 <section id="fe-sec-mini-cmd-t">
190 <title>SEC tone burst</title>
192 <para>The 22KHz tone burst is usually used with non-DiSEqC capable switches to select
193 between two connected LNBs/satellites. When using DiSEqC epuipment this voltage has to
194 be switched consistently to the DiSEqC commands as described in the DiSEqC
197 typedef enum fe_sec_mini_cmd {
206 <section id="fe-status-t">
207 <title>frontend status</title>
208 <para>Several functions of the frontend device use the fe_status data type defined
211 typedef enum fe_status {
212 FE_HAS_SIGNAL = 0x01,
213 FE_HAS_CARRIER = 0x02,
214 FE_HAS_VITERBI = 0x04,
221 <para>to indicate the current state and/or state changes of the frontend hardware:
224 <informaltable><tgroup cols="2"><tbody>
226 <entry align="char">FE_HAS_SIGNAL</entry>
227 <entry align="char">The frontend has found something above the noise level</entry>
229 <entry align="char">FE_HAS_CARRIER</entry>
230 <entry align="char">The frontend has found a DVB signal</entry>
232 <entry align="char">FE_HAS_VITERBI</entry>
233 <entry align="char">The frontend FEC inner coding (Viterbi, LDPC or other inner code) is stable</entry>
235 <entry align="char">FE_HAS_SYNC</entry>
236 <entry align="char">Synchronization bytes was found</entry>
238 <entry align="char">FE_HAS_LOCK</entry>
239 <entry align="char">The DVB were locked and everything is working</entry>
241 <entry align="char">FE_TIMEDOUT</entry>
242 <entry align="char">no lock within the last about 2 seconds</entry>
244 <entry align="char">FE_REINIT</entry>
245 <entry align="char">The frontend was reinitialized, application is
246 recommended to reset DiSEqC, tone and parameters</entry>
248 </tbody></tgroup></informaltable>
252 <section id="dvb-frontend-parameters">
253 <title>frontend parameters</title>
254 <para>The kind of parameters passed to the frontend device for tuning depend on
255 the kind of hardware you are using.</para>
256 <para>The struct <constant>dvb_frontend_parameters</constant> uses an
257 union with specific per-system parameters. However, as newer delivery systems
258 required more data, the structure size weren't enough to fit, and just
259 extending its size would break the existing applications. So, those parameters
260 were replaced by the usage of <link linkend="FE_GET_SET_PROPERTY">
261 <constant>FE_GET_PROPERTY/FE_SET_PROPERTY</constant></link> ioctl's. The
262 new API is flexible enough to add new parameters to existing delivery systems,
263 and to add newer delivery systems.</para>
264 <para>So, newer applications should use <link linkend="FE_GET_SET_PROPERTY">
265 <constant>FE_GET_PROPERTY/FE_SET_PROPERTY</constant></link> instead, in
266 order to be able to support the newer System Delivery like DVB-S2, DVB-T2,
267 DVB-C2, ISDB, etc.</para>
268 <para>All kinds of parameters are combined as an union in the FrontendParameters structure:
270 struct dvb_frontend_parameters {
271 uint32_t frequency; /⋆ (absolute) frequency in Hz for QAM/OFDM ⋆/
272 /⋆ intermediate frequency in kHz for QPSK ⋆/
273 fe_spectral_inversion_t inversion;
275 struct dvb_qpsk_parameters qpsk;
276 struct dvb_qam_parameters qam;
277 struct dvb_ofdm_parameters ofdm;
278 struct dvb_vsb_parameters vsb;
281 </programlisting></para>
282 <para>In the case of QPSK frontends the <constant>frequency</constant> field specifies the intermediate
283 frequency, i.e. the offset which is effectively added to the local oscillator frequency (LOF) of
284 the LNB. The intermediate frequency has to be specified in units of kHz. For QAM and
285 OFDM frontends the <constant>frequency</constant> specifies the absolute frequency and is given in Hz.
288 <section id="dvb-qpsk-parameters">
289 <title>QPSK parameters</title>
290 <para>For satellite QPSK frontends you have to use the <constant>dvb_qpsk_parameters</constant> structure:</para>
292 struct dvb_qpsk_parameters {
293 uint32_t symbol_rate; /⋆ symbol rate in Symbols per second ⋆/
294 fe_code_rate_t fec_inner; /⋆ forward error correction (see above) ⋆/
298 <section id="dvb-qam-parameters">
299 <title>QAM parameters</title>
300 <para>for cable QAM frontend you use the <constant>dvb_qam_parameters</constant> structure:</para>
302 struct dvb_qam_parameters {
303 uint32_t symbol_rate; /⋆ symbol rate in Symbols per second ⋆/
304 fe_code_rate_t fec_inner; /⋆ forward error correction (see above) ⋆/
305 fe_modulation_t modulation; /⋆ modulation type (see above) ⋆/
309 <section id="dvb-vsb-parameters">
310 <title>VSB parameters</title>
311 <para>ATSC frontends are supported by the <constant>dvb_vsb_parameters</constant> structure:</para>
313 struct dvb_vsb_parameters {
314 fe_modulation_t modulation; /⋆ modulation type (see above) ⋆/
318 <section id="dvb-ofdm-parameters">
319 <title>OFDM parameters</title>
320 <para>DVB-T frontends are supported by the <constant>dvb_ofdm_parameters</constant> structure:</para>
322 struct dvb_ofdm_parameters {
323 fe_bandwidth_t bandwidth;
324 fe_code_rate_t code_rate_HP; /⋆ high priority stream code rate ⋆/
325 fe_code_rate_t code_rate_LP; /⋆ low priority stream code rate ⋆/
326 fe_modulation_t constellation; /⋆ modulation type (see above) ⋆/
327 fe_transmit_mode_t transmission_mode;
328 fe_guard_interval_t guard_interval;
329 fe_hierarchy_t hierarchy_information;
333 <section id="fe-spectral-inversion-t">
334 <title>frontend spectral inversion</title>
335 <para>The Inversion field can take one of these values:
338 typedef enum fe_spectral_inversion {
342 } fe_spectral_inversion_t;
344 <para>It indicates if spectral inversion should be presumed or not. In the automatic setting
345 (<constant>INVERSION_AUTO</constant>) the hardware will try to figure out the correct setting by
349 <section id="fe-code-rate-t">
350 <title>frontend code rate</title>
351 <para>The possible values for the <constant>fec_inner</constant> field used on
352 <link linkend="dvb-qpsk-parameters"><constant>struct dvb_qpsk_parameters</constant></link> and
353 <link linkend="dvb-qam-parameters"><constant>struct dvb_qam_parameters</constant></link> are:
356 typedef enum fe_code_rate {
371 <para>which correspond to error correction rates of 1/2, 2/3, etc., no error correction or auto
375 <section id="fe-modulation-t">
376 <title>frontend modulation type for QAM, OFDM and VSB</title>
377 <para>For cable and terrestrial frontends, e. g. for
378 <link linkend="dvb-qam-parameters"><constant>struct dvb_qpsk_parameters</constant></link>,
379 <link linkend="dvb-ofdm-parameters"><constant>struct dvb_qam_parameters</constant></link> and
380 <link linkend="dvb-vsb-parameters"><constant>struct dvb_qam_parameters</constant></link>,
381 it needs to specify the quadrature modulation mode which can be one of the following:
384 typedef enum fe_modulation {
402 <title>More OFDM parameters</title>
403 <section id="fe-transmit-mode-t">
404 <title>Number of carriers per channel</title>
406 typedef enum fe_transmit_mode {
407 TRANSMISSION_MODE_2K,
408 TRANSMISSION_MODE_8K,
409 TRANSMISSION_MODE_AUTO,
410 TRANSMISSION_MODE_4K,
411 TRANSMISSION_MODE_1K,
412 TRANSMISSION_MODE_16K,
413 TRANSMISSION_MODE_32K,
414 } fe_transmit_mode_t;
417 <section id="fe-bandwidth-t">
418 <title>frontend bandwidth</title>
420 typedef enum fe_bandwidth {
431 <section id="fe-guard-interval-t">
432 <title>frontend guard inverval</title>
434 typedef enum fe_guard_interval {
440 GUARD_INTERVAL_1_128,
441 GUARD_INTERVAL_19_128,
442 GUARD_INTERVAL_19_256,
443 } fe_guard_interval_t;
446 <section id="fe-hierarchy-t">
447 <title>frontend hierarchy</title>
449 typedef enum fe_hierarchy {
462 <section id="dvb-frontend-event">
463 <title>frontend events</title>
465 struct dvb_frontend_event {
467 struct dvb_frontend_parameters parameters;
474 <section id="frontend_fcalls">
475 <title>Frontend Function Calls</title>
477 <section id="frontend_f_open">
478 <title>open()</title>
479 <para>DESCRIPTION</para>
480 <informaltable><tgroup cols="1"><tbody><row>
482 <para>This system call opens a named frontend device (/dev/dvb/adapter0/frontend0)
483 for subsequent use. Usually the first thing to do after a successful open is to
484 find out the frontend type with <link linkend="FE_GET_INFO">FE_GET_INFO</link>.</para>
485 <para>The device can be opened in read-only mode, which only allows monitoring of
486 device status and statistics, or read/write mode, which allows any kind of use
487 (e.g. performing tuning operations.)
489 <para>In a system with multiple front-ends, it is usually the case that multiple devices
490 cannot be open in read/write mode simultaneously. As long as a front-end
491 device is opened in read/write mode, other open() calls in read/write mode will
492 either fail or block, depending on whether non-blocking or blocking mode was
493 specified. A front-end device opened in blocking mode can later be put into
494 non-blocking mode (and vice versa) using the F_SETFL command of the fcntl
495 system call. This is a standard system call, documented in the Linux manual
496 page for fcntl. When an open() call has succeeded, the device will be ready
497 for use in the specified mode. This implies that the corresponding hardware is
498 powered up, and that other front-ends may have been powered down to make
499 that possible.</para>
501 </row></tbody></tgroup></informaltable>
503 <para>SYNOPSIS</para>
504 <informaltable><tgroup cols="1"><tbody><row><entry
506 <para>int open(const char ⋆deviceName, int flags);</para>
508 </row></tbody></tgroup></informaltable>
511 <informaltable><tgroup cols="2"><tbody><row><entry
517 <para>Name of specific video device.</para>
521 <para>int flags</para>
524 <para>A bit-wise OR of the following flags:</para>
530 <para>O_RDONLY read-only access</para>
536 <para>O_RDWR read/write access</para>
542 <para>O_NONBLOCK open in non-blocking mode</para>
548 <para>(blocking mode is the default)</para>
550 </row></tbody></tgroup></informaltable>
551 <para>RETURN VALUE</para>
552 <informaltable><tgroup cols="2"><tbody><row><entry
557 <para>Device driver not loaded/available.</para>
561 <para>EINTERNAL</para>
564 <para>Internal error.</para>
571 <para>Device or resource busy.</para>
578 <para>Invalid argument.</para>
580 </row></tbody></tgroup></informaltable>
583 <section id="frontend_f_close">
584 <title>close()</title>
587 <informaltable><tgroup cols="1"><tbody><row><entry
589 <para>This system call closes a previously opened front-end device. After closing
590 a front-end device, its corresponding hardware might be powered down
591 automatically.</para>
593 </row></tbody></tgroup></informaltable>
596 <informaltable><tgroup cols="1"><tbody><row><entry
598 <para>int close(int fd);</para>
600 </row></tbody></tgroup></informaltable>
603 <informaltable><tgroup cols="2"><tbody><row><entry
608 <para>File descriptor returned by a previous call to open().</para>
610 </row></tbody></tgroup></informaltable>
611 <para>RETURN VALUE</para>
612 <informaltable><tgroup cols="2"><tbody><row><entry
617 <para>fd is not a valid open file descriptor.</para>
619 </row></tbody></tgroup></informaltable>
622 <section id="FE_READ_STATUS">
623 <title>FE_READ_STATUS</title>
626 <informaltable><tgroup cols="1"><tbody><row><entry
628 <para>This ioctl call returns status information about the front-end. This call only
629 requires read-only access to the device.</para>
631 </row></tbody></tgroup></informaltable>
634 <informaltable><tgroup cols="1"><tbody><row><entry
636 <para>int ioctl(int fd, int request = <link linkend="FE_READ_STATUS">FE_READ_STATUS</link>,
637 fe_status_t ⋆status);</para>
639 </row></tbody></tgroup></informaltable>
643 <informaltable><tgroup cols="2"><tbody><row><entry
648 <para>File descriptor returned by a previous call to open().</para>
652 <para>int request</para>
655 <para>Equals <link linkend="FE_READ_STATUS">FE_READ_STATUS</link> for this command.</para>
659 <para>struct fe_status_t
663 <para>Points to the location where the front-end status word is
666 </row></tbody></tgroup></informaltable>
667 <para>RETURN VALUE</para>
668 <informaltable><tgroup cols="2"><tbody><row><entry
673 <para>fd is not a valid open file descriptor.</para>
680 <para>status points to invalid address.</para>
682 </row></tbody></tgroup></informaltable>
685 <section id="FE_READ_BER">
686 <title>FE_READ_BER</title>
689 <informaltable><tgroup cols="1"><tbody><row><entry
691 <para>This ioctl call returns the bit error rate for the signal currently
692 received/demodulated by the front-end. For this command, read-only access to
693 the device is sufficient.</para>
695 </row></tbody></tgroup></informaltable>
698 <informaltable><tgroup cols="1"><tbody><row><entry
700 <para>int ioctl(int fd, int request = <link linkend="FE_READ_BER">FE_READ_BER</link>,
701 uint32_t ⋆ber);</para>
703 </row></tbody></tgroup></informaltable>
706 <informaltable><tgroup cols="2"><tbody><row><entry
711 <para>File descriptor returned by a previous call to open().</para>
715 <para>int request</para>
718 <para>Equals <link linkend="FE_READ_BER">FE_READ_BER</link> for this command.</para>
722 <para>uint32_t *ber</para>
725 <para>The bit error rate is stored into *ber.</para>
727 </row></tbody></tgroup></informaltable>
732 <section id="FE_READ_SNR">
733 <title>FE_READ_SNR</title>
737 <informaltable><tgroup cols="1"><tbody><row><entry
739 <para>This ioctl call returns the signal-to-noise ratio for the signal currently received
740 by the front-end. For this command, read-only access to the device is sufficient.</para>
742 </row></tbody></tgroup></informaltable>
745 <informaltable><tgroup cols="1"><tbody><row><entry
747 <para>int ioctl(int fd, int request = <link linkend="FE_READ_SNR">FE_READ_SNR</link>, uint16_t
750 </row></tbody></tgroup></informaltable>
753 <informaltable><tgroup cols="2"><tbody><row><entry
758 <para>File descriptor returned by a previous call to open().</para>
762 <para>int request</para>
765 <para>Equals <link linkend="FE_READ_SNR">FE_READ_SNR</link> for this command.</para>
769 <para>uint16_t *snr</para>
772 <para>The signal-to-noise ratio is stored into *snr.</para>
774 </row></tbody></tgroup></informaltable>
779 <section id="FE_READ_SIGNAL_STRENGTH">
780 <title>FE_READ_SIGNAL_STRENGTH</title>
783 <informaltable><tgroup cols="1"><tbody><row><entry
785 <para>This ioctl call returns the signal strength value for the signal currently received
786 by the front-end. For this command, read-only access to the device is sufficient.</para>
788 </row></tbody></tgroup></informaltable>
791 <informaltable><tgroup cols="1"><tbody><row><entry
793 <para>int ioctl( int fd, int request =
794 <link linkend="FE_READ_SIGNAL_STRENGTH">FE_READ_SIGNAL_STRENGTH</link>, uint16_t ⋆strength);</para>
796 </row></tbody></tgroup></informaltable>
800 <informaltable><tgroup cols="2"><tbody><row><entry
805 <para>File descriptor returned by a previous call to open().</para>
809 <para>int request</para>
812 <para>Equals <link linkend="FE_READ_SIGNAL_STRENGTH">FE_READ_SIGNAL_STRENGTH</link> for this
817 <para>uint16_t *strength</para>
820 <para>The signal strength value is stored into *strength.</para>
822 </row></tbody></tgroup></informaltable>
827 <section id="FE_READ_UNCORRECTED_BLOCKS">
828 <title>FE_READ_UNCORRECTED_BLOCKS</title>
831 <informaltable><tgroup cols="1"><tbody><row><entry
833 <para>This ioctl call returns the number of uncorrected blocks detected by the device
834 driver during its lifetime. For meaningful measurements, the increment in block
835 count during a specific time interval should be calculated. For this command,
836 read-only access to the device is sufficient.</para>
840 <para>Note that the counter will wrap to zero after its maximum count has been
843 </row></tbody></tgroup></informaltable>
846 <informaltable><tgroup cols="1"><tbody><row><entry
848 <para>int ioctl( int fd, int request =
849 <link linkend="FE_READ_UNCORRECTED_BLOCKS">FE_READ_UNCORRECTED_BLOCKS</link>, uint32_t ⋆ublocks);</para>
851 </row></tbody></tgroup></informaltable>
854 <informaltable><tgroup cols="2"><tbody><row><entry
859 <para>File descriptor returned by a previous call to open().</para>
863 <para>int request</para>
866 <para>Equals <link linkend="FE_READ_UNCORRECTED_BLOCKS">FE_READ_UNCORRECTED_BLOCKS</link> for this
871 <para>uint32_t *ublocks</para>
874 <para>The total number of uncorrected blocks seen by the driver
877 </row></tbody></tgroup></informaltable>
882 <section id="FE_SET_FRONTEND">
883 <title>FE_SET_FRONTEND</title>
886 <informaltable><tgroup cols="1"><tbody><row><entry
888 <para>This ioctl call starts a tuning operation using specified parameters. The result
889 of this call will be successful if the parameters were valid and the tuning could
890 be initiated. The result of the tuning operation in itself, however, will arrive
891 asynchronously as an event (see documentation for <link linkend="FE_GET_EVENT">FE_GET_EVENT</link> and
892 FrontendEvent.) If a new <link linkend="FE_SET_FRONTEND">FE_SET_FRONTEND</link> operation is initiated before
893 the previous one was completed, the previous operation will be aborted in favor
894 of the new one. This command requires read/write access to the device.</para>
896 </row></tbody></tgroup></informaltable>
900 <informaltable><tgroup cols="1"><tbody><row><entry
902 <para>int ioctl(int fd, int request = <link linkend="FE_SET_FRONTEND">FE_SET_FRONTEND</link>,
903 struct dvb_frontend_parameters ⋆p);</para>
905 </row></tbody></tgroup></informaltable>
908 <informaltable><tgroup cols="2"><tbody><row><entry
913 <para>File descriptor returned by a previous call to open().</para>
917 <para>int request</para>
920 <para>Equals <link linkend="FE_SET_FRONTEND">FE_SET_FRONTEND</link> for this command.</para>
925 dvb_frontend_parameters
929 <para>Points to parameters for tuning operation.</para>
931 </row></tbody></tgroup></informaltable>
934 <informaltable><tgroup cols="2"><tbody><row><entry
939 <para>Maximum supported symbol rate reached.</para>
941 </row></tbody></tgroup></informaltable>
944 <section id="FE_GET_FRONTEND">
945 <title>FE_GET_FRONTEND</title>
948 <informaltable><tgroup cols="1"><tbody><row><entry
950 <para>This ioctl call queries the currently effective frontend parameters. For this
951 command, read-only access to the device is sufficient.</para>
953 </row></tbody></tgroup></informaltable>
957 <informaltable><tgroup cols="1"><tbody><row><entry
959 <para>int ioctl(int fd, int request = <link linkend="FE_GET_FRONTEND">FE_GET_FRONTEND</link>,
960 struct dvb_frontend_parameters ⋆p);</para>
962 </row></tbody></tgroup></informaltable>
966 <informaltable><tgroup cols="2"><tbody><row><entry
971 <para>File descriptor returned by a previous call to open().</para>
975 <para>int request</para>
978 <para>Equals <link linkend="FE_SET_FRONTEND">FE_SET_FRONTEND</link> for this command.</para>
983 dvb_frontend_parameters
987 <para>Points to parameters for tuning operation.</para>
989 </row></tbody></tgroup></informaltable>
992 <informaltable><tgroup cols="2"><tbody><row><entry
997 <para>Maximum supported symbol rate reached.</para>
999 </row></tbody></tgroup></informaltable>
1003 <section id="FE_GET_EVENT">
1004 <title>FE_GET_EVENT</title>
1007 <informaltable><tgroup cols="1"><tbody><row><entry
1009 <para>This ioctl call returns a frontend event if available. If an event is not
1010 available, the behavior depends on whether the device is in blocking or
1011 non-blocking mode. In the latter case, the call fails immediately with errno
1012 set to EWOULDBLOCK. In the former case, the call blocks until an event
1013 becomes available.</para>
1017 <para>The standard Linux poll() and/or select() system calls can be used with the
1018 device file descriptor to watch for new events. For select(), the file descriptor
1019 should be included in the exceptfds argument, and for poll(), POLLPRI should
1020 be specified as the wake-up condition. Since the event queue allocated is
1021 rather small (room for 8 events), the queue must be serviced regularly to avoid
1022 overflow. If an overflow happens, the oldest event is discarded from the queue,
1023 and an error (EOVERFLOW) occurs the next time the queue is read. After
1024 reporting the error condition in this fashion, subsequent
1025 <link linkend="FE_GET_EVENT">FE_GET_EVENT</link>
1026 calls will return events from the queue as usual.</para>
1030 <para>For the sake of implementation simplicity, this command requires read/write
1031 access to the device.</para>
1033 </row></tbody></tgroup></informaltable>
1037 <informaltable><tgroup cols="1"><tbody><row><entry
1039 <para>int ioctl(int fd, int request = QPSK_GET_EVENT,
1040 struct dvb_frontend_event ⋆ev);</para>
1042 </row></tbody></tgroup></informaltable>
1046 <informaltable><tgroup cols="2"><tbody><row><entry
1051 <para>File descriptor returned by a previous call to open().</para>
1055 <para>int request</para>
1058 <para>Equals <link linkend="FE_GET_EVENT">FE_GET_EVENT</link> for this command.</para>
1067 <para>Points to the location where the event,</para>
1073 <para>if any, is to be stored.</para>
1075 </row></tbody></tgroup></informaltable>
1078 <informaltable><tgroup cols="2"><tbody><row><entry
1080 <para>EWOULDBLOCK</para>
1083 <para>There is no event pending, and the device is in
1084 non-blocking mode.</para>
1088 <para>EOVERFLOW</para>
1091 <para>Overflow in event queue - one or more events were lost.</para>
1093 </row></tbody></tgroup></informaltable>
1096 <section id="FE_GET_INFO">
1097 <title>FE_GET_INFO</title>
1100 <informaltable><tgroup cols="1"><tbody><row><entry
1102 <para>This ioctl call returns information about the front-end. This call only requires
1103 read-only access to the device.</para>
1105 </row></tbody></tgroup></informaltable>
1109 <informaltable><tgroup cols="1"><tbody><row><entry
1111 <para> int ioctl(int fd, int request = <link linkend="FE_GET_INFO">FE_GET_INFO</link>, struct
1112 dvb_frontend_info ⋆info);</para>
1114 </row></tbody></tgroup></informaltable>
1118 <informaltable><tgroup cols="2"><tbody><row><entry
1123 <para>File descriptor returned by a previous call to open().</para>
1127 <para>int request</para>
1130 <para>Equals <link linkend="FE_GET_INFO">FE_GET_INFO</link> for this command.</para>
1139 <para>Points to the location where the front-end information is
1140 to be stored.</para>
1142 </row></tbody></tgroup></informaltable>
1146 <section id="FE_DISEQC_RESET_OVERLOAD">
1147 <title>FE_DISEQC_RESET_OVERLOAD</title>
1150 <informaltable><tgroup cols="1"><tbody><row><entry
1152 <para>If the bus has been automatically powered off due to power overload, this ioctl
1153 call restores the power to the bus. The call requires read/write access to the
1154 device. This call has no effect if the device is manually powered off. Not all
1155 DVB adapters support this ioctl.</para>
1157 </row></tbody></tgroup></informaltable>
1161 <informaltable><tgroup cols="1"><tbody><row><entry
1163 <para>int ioctl(int fd, int request =
1164 <link linkend="FE_DISEQC_RESET_OVERLOAD">FE_DISEQC_RESET_OVERLOAD</link>);</para>
1166 </row></tbody></tgroup></informaltable>
1169 <informaltable><tgroup cols="2"><tbody><row><entry
1174 <para>File descriptor returned by a previous call to open().</para>
1178 <para>int request</para>
1181 <para>Equals <link linkend="FE_DISEQC_RESET_OVERLOAD">FE_DISEQC_RESET_OVERLOAD</link> for this
1184 </row></tbody></tgroup></informaltable>
1189 <section id="FE_DISEQC_SEND_MASTER_CMD">
1190 <title>FE_DISEQC_SEND_MASTER_CMD</title>
1193 <informaltable><tgroup cols="1"><tbody><row><entry
1195 <para>This ioctl call is used to send a a DiSEqC command.</para>
1197 </row></tbody></tgroup></informaltable>
1200 <informaltable><tgroup cols="1"><tbody><row><entry
1202 <para>int ioctl(int fd, int request =
1203 <link linkend="FE_DISEQC_SEND_MASTER_CMD">FE_DISEQC_SEND_MASTER_CMD</link>, struct
1204 dvb_diseqc_master_cmd ⋆cmd);</para>
1206 </row></tbody></tgroup></informaltable>
1210 <informaltable><tgroup cols="2"><tbody><row><entry
1215 <para>File descriptor returned by a previous call to open().</para>
1219 <para>int request</para>
1222 <para>Equals <link linkend="FE_DISEQC_SEND_MASTER_CMD">FE_DISEQC_SEND_MASTER_CMD</link> for this
1228 dvb_diseqc_master_cmd
1232 <para>Pointer to the command to be transmitted.</para>
1234 </row></tbody></tgroup></informaltable>
1239 <section id="FE_DISEQC_RECV_SLAVE_REPLY">
1240 <title>FE_DISEQC_RECV_SLAVE_REPLY</title>
1243 <informaltable><tgroup cols="1"><tbody><row><entry
1245 <para>This ioctl call is used to receive reply to a DiSEqC 2.0 command.</para>
1247 </row></tbody></tgroup></informaltable>
1251 <informaltable><tgroup cols="1"><tbody><row><entry
1253 <para>int ioctl(int fd, int request =
1254 <link linkend="FE_DISEQC_RECV_SLAVE_REPLY">FE_DISEQC_RECV_SLAVE_REPLY</link>, struct
1255 dvb_diseqc_slave_reply ⋆reply);</para>
1257 </row></tbody></tgroup></informaltable>
1261 <informaltable><tgroup cols="2"><tbody><row><entry
1266 <para>File descriptor returned by a previous call to open().</para>
1270 <para>int request</para>
1273 <para>Equals <link linkend="FE_DISEQC_RECV_SLAVE_REPLY">FE_DISEQC_RECV_SLAVE_REPLY</link> for this
1279 dvb_diseqc_slave_reply
1283 <para>Pointer to the command to be received.</para>
1285 </row></tbody></tgroup></informaltable>
1289 <section id="FE_DISEQC_SEND_BURST">
1290 <title>FE_DISEQC_SEND_BURST</title>
1293 <informaltable><tgroup cols="1"><tbody><row><entry
1295 <para>This ioctl call is used to send a 22KHz tone burst.</para>
1297 </row></tbody></tgroup></informaltable>
1301 <informaltable><tgroup cols="1"><tbody><row><entry
1303 <para>int ioctl(int fd, int request =
1304 <link linkend="FE_DISEQC_SEND_BURST">FE_DISEQC_SEND_BURST</link>, fe_sec_mini_cmd_t burst);</para>
1306 </row></tbody></tgroup></informaltable>
1310 <informaltable><tgroup cols="2"><tbody><row><entry
1315 <para>File descriptor returned by a previous call to open().</para>
1319 <para>int request</para>
1322 <para>Equals <link linkend="FE_DISEQC_SEND_BURST">FE_DISEQC_SEND_BURST</link> for this command.</para>
1326 <para>fe_sec_mini_cmd_t
1330 <para>burst A or B.</para>
1332 </row></tbody></tgroup></informaltable>
1337 <section id="FE_SET_TONE">
1338 <title>FE_SET_TONE</title>
1341 <informaltable><tgroup cols="1"><tbody><row><entry
1343 <para>This call is used to set the generation of the continuous 22kHz tone. This call
1344 requires read/write permissions.</para>
1346 </row></tbody></tgroup></informaltable>
1349 <informaltable><tgroup cols="1"><tbody><row><entry
1351 <para>int ioctl(int fd, int request = <link linkend="FE_SET_TONE">FE_SET_TONE</link>,
1352 fe_sec_tone_mode_t tone);</para>
1354 </row></tbody></tgroup></informaltable>
1357 <informaltable><tgroup cols="2"><tbody><row><entry
1362 <para>File descriptor returned by a previous call to open().</para>
1366 <para>int request</para>
1369 <para>Equals <link linkend="FE_SET_TONE">FE_SET_TONE</link> for this command.</para>
1373 <para>fe_sec_tone_mode_t
1377 <para>The requested tone generation mode (on/off).</para>
1379 </row></tbody></tgroup></informaltable>
1383 <section id="FE_SET_VOLTAGE">
1384 <title>FE_SET_VOLTAGE</title>
1387 <informaltable><tgroup cols="1"><tbody><row><entry
1389 <para>This call is used to set the bus voltage. This call requires read/write
1392 </row></tbody></tgroup></informaltable>
1395 <informaltable><tgroup cols="1"><tbody><row><entry
1397 <para>int ioctl(int fd, int request = <link linkend="FE_SET_VOLTAGE">FE_SET_VOLTAGE</link>,
1398 fe_sec_voltage_t voltage);</para>
1400 </row></tbody></tgroup></informaltable>
1404 <informaltable><tgroup cols="2"><tbody><row><entry
1409 <para>File descriptor returned by a previous call to open().</para>
1413 <para>int request</para>
1416 <para>Equals <link linkend="FE_SET_VOLTAGE">FE_SET_VOLTAGE</link> for this command.</para>
1420 <para>fe_sec_voltage_t
1424 <para>The requested bus voltage.</para>
1426 </row></tbody></tgroup></informaltable>
1431 <section id="FE_ENABLE_HIGH_LNB_VOLTAGE">
1432 <title>FE_ENABLE_HIGH_LNB_VOLTAGE</title>
1435 <informaltable><tgroup cols="1"><tbody><row><entry
1437 <para>If high != 0 enables slightly higher voltages instead of 13/18V (to compensate
1438 for long cables). This call requires read/write permissions. Not all DVB
1439 adapters support this ioctl.</para>
1441 </row></tbody></tgroup></informaltable>
1445 <informaltable><tgroup cols="1"><tbody><row><entry
1447 <para>int ioctl(int fd, int request =
1448 <link linkend="FE_ENABLE_HIGH_LNB_VOLTAGE">FE_ENABLE_HIGH_LNB_VOLTAGE</link>, int high);</para>
1450 </row></tbody></tgroup></informaltable>
1454 <informaltable><tgroup cols="2"><tbody><row><entry
1459 <para>File descriptor returned by a previous call to open().</para>
1463 <para>int request</para>
1466 <para>Equals <link linkend="FE_SET_VOLTAGE">FE_SET_VOLTAGE</link> for this command.</para>
1470 <para>int high</para>
1473 <para>The requested bus voltage.</para>
1475 </row></tbody></tgroup></informaltable>
1480 <section id="FE_SET_FRONTEND_TUNE_MODE">
1481 <title>FE_SET_FRONTEND_TUNE_MODE</title>
1482 <para>DESCRIPTION</para>
1483 <informaltable><tgroup cols="1"><tbody><row>
1484 <entry align="char">
1485 <para>Allow setting tuner mode flags to the frontend.</para>
1487 </row></tbody></tgroup></informaltable>
1489 <para>SYNOPSIS</para>
1490 <informaltable><tgroup cols="1"><tbody><row>
1491 <entry align="char">
1492 <para>int ioctl(int fd, int request =
1493 <link linkend="FE_SET_FRONTEND_TUNE_MODE">FE_SET_FRONTEND_TUNE_MODE</link>, unsigned int flags);</para>
1495 </row></tbody></tgroup></informaltable>
1497 <para>PARAMETERS</para>
1498 <informaltable><tgroup cols="2"><tbody><row>
1499 <entry align="char">
1500 <para>unsigned int flags</para>
1502 <entry align="char">
1504 FE_TUNE_MODE_ONESHOT When set, this flag will disable any zigzagging or other "normal" tuning behaviour. Additionally, there will be no automatic monitoring of the lock status, and hence no frontend events will be generated. If a frontend device is closed, this flag will be automatically turned off when the device is reopened read-write.
1507 </row></tbody></tgroup></informaltable>
1512 <section id="FE_DISHNETWORK_SEND_LEGACY_CMD">
1513 <title>FE_DISHNETWORK_SEND_LEGACY_CMD</title>
1514 <para>DESCRIPTION</para>
1515 <informaltable><tgroup cols="1"><tbody><row>
1516 <entry align="char">
1517 <para>WARNING: This is a very obscure legacy command, used only at stv0299 driver. Should not be used on newer drivers.</para>
1518 <para>It provides a non-standard method for selecting Diseqc voltage on the frontend, for Dish Network legacy switches.</para>
1519 <para>As support for this ioctl were added in 2004, this means that such dishes were already legacy in 2004.</para>
1521 </row></tbody></tgroup></informaltable>
1523 <para>SYNOPSIS</para>
1524 <informaltable><tgroup cols="1"><tbody><row>
1525 <entry align="char">
1526 <para>int ioctl(int fd, int request =
1527 <link linkend="FE_DISHNETWORK_SEND_LEGACY_CMD">FE_DISHNETWORK_SEND_LEGACY_CMD</link>, unsigned long cmd);</para>
1529 </row></tbody></tgroup></informaltable>
1531 <para>PARAMETERS</para>
1532 <informaltable><tgroup cols="2"><tbody><row>
1533 <entry align="char">
1534 <para>unsigned long cmd</para>
1536 <entry align="char">
1538 sends the specified raw cmd to the dish via DISEqC.
1541 </row></tbody></tgroup></informaltable>