About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Documentation / DocBook / media / dvb / frontend.xml




Custom Search

Based on kernel version 3.15.4. Page generated on 2014-07-07 09:02 EST.

1	<title>DVB Frontend API</title>
2	
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>
8	
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>
16	
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>
19	
20	<section id="frontend_types">
21	<title>Frontend Data Types</title>
22	
23	<section id="fe-type-t">
24	<title>Frontend type</title>
25	
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>
28	
29	<table pgwide="1" frame="none" id="fe-type">
30	<title>Frontend types</title>
31	<tgroup cols="3">
32	   &cs-def;
33	   <thead>
34	     <row>
35	       <entry>fe_type</entry>
36	       <entry>Description</entry>
37	       <entry><link linkend="DTV-DELIVERY-SYSTEM">DTV_DELIVERY_SYSTEM</link> equivalent type</entry>
38	     </row>
39	  </thead>
40	  <tbody valign="top">
41	  <row>
42	     <entry id="FE_QPSK"><constant>FE_QPSK</constant></entry>
43	     <entry>For DVB-S standard</entry>
44	     <entry><constant>SYS_DVBS</constant></entry>
45	  </row>
46	  <row>
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>
50	  </row>
51	  <row>
52	     <entry id="FE_OFDM"><constant>FE_OFDM</constant></entry>
53	     <entry>For DVB-T standard</entry>
54	     <entry><constant>SYS_DVBT</constant></entry>
55	  </row>
56	  <row>
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>
60	  </row>
61	</tbody></tgroup></table>
62	
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.
65	</para>
66	
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>
70	</section>
71	
72	<section id="fe-caps-t">
73	<title>frontend capabilities</title>
74	
75	<para>Capabilities describe what a frontend can do. Some capabilities can only be supported for
76	a specific frontend type.</para>
77	<programlisting>
78		typedef enum fe_caps {
79		FE_IS_STUPID                  = 0,
80		FE_CAN_INVERSION_AUTO         = 0x1,
81		FE_CAN_FEC_1_2                = 0x2,
82		FE_CAN_FEC_2_3                = 0x4,
83		FE_CAN_FEC_3_4                = 0x8,
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,
90		FE_CAN_QPSK                   = 0x400,
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
110		} fe_caps_t;
111	</programlisting>
112	</section>
113	
114	<section id="dvb-frontend-info">
115	<title>frontend information</title>
116	
117	<para>Information about the frontend ca be queried with
118		<link linkend="FE_GET_INFO">FE_GET_INFO</link>.</para>
119	
120	<programlisting>
121		struct dvb_frontend_info {
122		char       name[128];
123		fe_type_t  type;
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;     /&#x22C6; ppm &#x22C6;/
131		uint32_t   notifier_delay;            /&#x22C6; ms &#x22C6;/
132		fe_caps_t  caps;
133		};
134	</programlisting>
135	</section>
136	
137	<section id="dvb-diseqc-master-cmd">
138	<title>diseqc master command</title>
139	
140	<para>A message sent from the frontend to DiSEqC capable equipment.</para>
141	<programlisting>
142		struct dvb_diseqc_master_cmd {
143		uint8_t msg [6]; /&#x22C6;  { framing, address, command, data[3] } &#x22C6;/
144		uint8_t msg_len; /&#x22C6;  valid values are 3...6  &#x22C6;/
145		};
146	</programlisting>
147	</section>
148	<section role="subsection" id="dvb-diseqc-slave-reply">
149	<title>diseqc slave reply</title>
150	
151	<para>A reply to the frontend from DiSEqC 2.0 capable equipment.</para>
152	<programlisting>
153		struct dvb_diseqc_slave_reply {
154		uint8_t msg [4]; /&#x22C6;  { framing, data [3] } &#x22C6;/
155		uint8_t msg_len; /&#x22C6;  valid values are 0...4, 0 means no msg  &#x22C6;/
156		int     timeout; /&#x22C6;  return from ioctl after timeout ms with &#x22C6;/
157		};                       /&#x22C6;  errorcode when no message was received  &#x22C6;/
158	</programlisting>
159	</section>
160	
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>
166	<programlisting>
167		typedef enum fe_sec_voltage {
168		SEC_VOLTAGE_13,
169		SEC_VOLTAGE_18
170		} fe_sec_voltage_t;
171	</programlisting>
172	</section>
173	
174	<section id="fe-sec-tone-mode-t">
175	<title>SEC continuous tone</title>
176	
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
180	spec.</para>
181	<programlisting>
182		typedef enum fe_sec_tone_mode {
183		SEC_TONE_ON,
184		SEC_TONE_OFF
185		} fe_sec_tone_mode_t;
186	</programlisting>
187	</section>
188	
189	<section id="fe-sec-mini-cmd-t">
190	<title>SEC tone burst</title>
191	
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
195	spec.</para>
196	<programlisting>
197		typedef enum fe_sec_mini_cmd {
198		SEC_MINI_A,
199		SEC_MINI_B
200		} fe_sec_mini_cmd_t;
201	</programlisting>
202	
203	<para></para>
204	</section>
205	
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
209	by</para>
210	<programlisting>
211	typedef enum fe_status {
212		FE_HAS_SIGNAL		= 0x01,
213		FE_HAS_CARRIER		= 0x02,
214		FE_HAS_VITERBI		= 0x04,
215		FE_HAS_SYNC		= 0x08,
216		FE_HAS_LOCK		= 0x10,
217		FE_TIMEDOUT		= 0x20,
218		FE_REINIT		= 0x40,
219	} fe_status_t;
220	</programlisting>
221	<para>to indicate the current state and/or state changes of the frontend hardware:
222	</para>
223	
224	<informaltable><tgroup cols="2"><tbody>
225	<row>
226	<entry align="char">FE_HAS_SIGNAL</entry>
227	<entry align="char">The frontend has found something above the noise level</entry>
228	</row><row>
229	<entry align="char">FE_HAS_CARRIER</entry>
230	<entry align="char">The frontend has found a DVB signal</entry>
231	</row><row>
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>
234	</row><row>
235	<entry align="char">FE_HAS_SYNC</entry>
236	<entry align="char">Synchronization bytes was found</entry>
237	</row><row>
238	<entry align="char">FE_HAS_LOCK</entry>
239	<entry align="char">The DVB were locked and everything is working</entry>
240	</row><row>
241	<entry align="char">FE_TIMEDOUT</entry>
242	<entry align="char">no lock within the last about 2 seconds</entry>
243	</row><row>
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>
247	</row>
248	</tbody></tgroup></informaltable>
249	
250	</section>
251	
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:
269	<programlisting>
270	struct dvb_frontend_parameters {
271		uint32_t frequency;     /&#x22C6; (absolute) frequency in Hz for QAM/OFDM &#x22C6;/
272					/&#x22C6; intermediate frequency in kHz for QPSK &#x22C6;/
273		fe_spectral_inversion_t inversion;
274		union {
275			struct dvb_qpsk_parameters qpsk;
276			struct dvb_qam_parameters  qam;
277			struct dvb_ofdm_parameters ofdm;
278			struct dvb_vsb_parameters  vsb;
279		} u;
280	};
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.
286	</para>
287	
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>
291	<programlisting>
292	 struct dvb_qpsk_parameters {
293		 uint32_t        symbol_rate;  /&#x22C6; symbol rate in Symbols per second &#x22C6;/
294		 fe_code_rate_t  fec_inner;    /&#x22C6; forward error correction (see above) &#x22C6;/
295	 };
296	</programlisting>
297	</section>
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>
301	<programlisting>
302	 struct dvb_qam_parameters {
303		 uint32_t         symbol_rate; /&#x22C6; symbol rate in Symbols per second &#x22C6;/
304		 fe_code_rate_t   fec_inner;   /&#x22C6; forward error correction (see above) &#x22C6;/
305		 fe_modulation_t  modulation;  /&#x22C6; modulation type (see above) &#x22C6;/
306	 };
307	</programlisting>
308	</section>
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>
312	<programlisting>
313	struct dvb_vsb_parameters {
314		fe_modulation_t modulation;	/&#x22C6; modulation type (see above) &#x22C6;/
315	};
316	</programlisting>
317	</section>
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>
321	<programlisting>
322	 struct dvb_ofdm_parameters {
323		 fe_bandwidth_t      bandwidth;
324		 fe_code_rate_t      code_rate_HP;  /&#x22C6; high priority stream code rate &#x22C6;/
325		 fe_code_rate_t      code_rate_LP;  /&#x22C6; low priority stream code rate &#x22C6;/
326		 fe_modulation_t     constellation; /&#x22C6; modulation type (see above) &#x22C6;/
327		 fe_transmit_mode_t  transmission_mode;
328		 fe_guard_interval_t guard_interval;
329		 fe_hierarchy_t      hierarchy_information;
330	 };
331	</programlisting>
332	</section>
333	<section id="fe-spectral-inversion-t">
334	<title>frontend spectral inversion</title>
335	<para>The Inversion field can take one of these values:
336	</para>
337	<programlisting>
338	typedef enum fe_spectral_inversion {
339		INVERSION_OFF,
340		INVERSION_ON,
341		INVERSION_AUTO
342	} fe_spectral_inversion_t;
343	</programlisting>
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
346	itself.
347	</para>
348	</section>
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:
354	</para>
355	<programlisting>
356	typedef enum fe_code_rate {
357		FEC_NONE = 0,
358		FEC_1_2,
359		FEC_2_3,
360		FEC_3_4,
361		FEC_4_5,
362		FEC_5_6,
363		FEC_6_7,
364		FEC_7_8,
365		FEC_8_9,
366		FEC_AUTO,
367		FEC_3_5,
368		FEC_9_10,
369	} fe_code_rate_t;
370	</programlisting>
371	<para>which correspond to error correction rates of 1/2, 2/3, etc., no error correction or auto
372	detection.
373	</para>
374	</section>
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:
382	</para>
383	<programlisting>
384	 typedef enum fe_modulation {
385		QPSK,
386		QAM_16,
387		QAM_32,
388		QAM_64,
389		QAM_128,
390		QAM_256,
391		QAM_AUTO,
392		VSB_8,
393		VSB_16,
394		PSK_8,
395		APSK_16,
396		APSK_32,
397		DQPSK,
398	 } fe_modulation_t;
399	</programlisting>
400	</section>
401	<section>
402	<title>More OFDM parameters</title>
403	<section id="fe-transmit-mode-t">
404	<title>Number of carriers per channel</title>
405	<programlisting>
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;
415	</programlisting>
416	</section>
417	<section id="fe-bandwidth-t">
418	<title>frontend bandwidth</title>
419	<programlisting>
420	typedef enum fe_bandwidth {
421		BANDWIDTH_8_MHZ,
422		BANDWIDTH_7_MHZ,
423		BANDWIDTH_6_MHZ,
424		BANDWIDTH_AUTO,
425		BANDWIDTH_5_MHZ,
426		BANDWIDTH_10_MHZ,
427		BANDWIDTH_1_712_MHZ,
428	} fe_bandwidth_t;
429	</programlisting>
430	</section>
431	<section id="fe-guard-interval-t">
432	<title>frontend guard inverval</title>
433	<programlisting>
434	typedef enum fe_guard_interval {
435		GUARD_INTERVAL_1_32,
436		GUARD_INTERVAL_1_16,
437		GUARD_INTERVAL_1_8,
438		GUARD_INTERVAL_1_4,
439		GUARD_INTERVAL_AUTO,
440		GUARD_INTERVAL_1_128,
441		GUARD_INTERVAL_19_128,
442		GUARD_INTERVAL_19_256,
443	} fe_guard_interval_t;
444	</programlisting>
445	</section>
446	<section id="fe-hierarchy-t">
447	<title>frontend hierarchy</title>
448	<programlisting>
449	typedef enum fe_hierarchy {
450		 HIERARCHY_NONE,
451		 HIERARCHY_1,
452		 HIERARCHY_2,
453		 HIERARCHY_4,
454		 HIERARCHY_AUTO
455	 } fe_hierarchy_t;
456	</programlisting>
457	</section>
458	</section>
459	
460	</section>
461	
462	<section id="dvb-frontend-event">
463	<title>frontend events</title>
464	 <programlisting>
465	 struct dvb_frontend_event {
466		 fe_status_t status;
467		 struct dvb_frontend_parameters parameters;
468	 };
469	</programlisting>
470	 </section>
471	</section>
472	
473	
474	<section id="frontend_fcalls">
475	<title>Frontend Function Calls</title>
476	
477	<section id="frontend_f_open">
478	<title>open()</title>
479	<para>DESCRIPTION</para>
480	<informaltable><tgroup cols="1"><tbody><row>
481	<entry align="char">
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.)
488	</para>
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>
500	</entry>
501	 </row></tbody></tgroup></informaltable>
502	
503	<para>SYNOPSIS</para>
504	<informaltable><tgroup cols="1"><tbody><row><entry
505	 align="char">
506	<para>int open(const char &#x22C6;deviceName, int flags);</para>
507	</entry>
508	 </row></tbody></tgroup></informaltable>
509	<para>PARAMETERS
510	</para>
511	<informaltable><tgroup cols="2"><tbody><row><entry
512	 align="char">
513	<para>const char
514	 *deviceName</para>
515	</entry><entry
516	 align="char">
517	<para>Name of specific video device.</para>
518	</entry>
519	 </row><row><entry
520	 align="char">
521	<para>int flags</para>
522	</entry><entry
523	 align="char">
524	<para>A bit-wise OR of the following flags:</para>
525	</entry>
526	 </row><row><entry
527	 align="char">
528	</entry><entry
529	 align="char">
530	<para>O_RDONLY read-only access</para>
531	</entry>
532	 </row><row><entry
533	 align="char">
534	</entry><entry
535	 align="char">
536	<para>O_RDWR read/write access</para>
537	</entry>
538	 </row><row><entry
539	 align="char">
540	</entry><entry
541	 align="char">
542	<para>O_NONBLOCK open in non-blocking mode</para>
543	</entry>
544	 </row><row><entry
545	 align="char">
546	</entry><entry
547	 align="char">
548	<para>(blocking mode is the default)</para>
549	</entry>
550	 </row></tbody></tgroup></informaltable>
551	<para>RETURN VALUE</para>
552	<informaltable><tgroup cols="2"><tbody><row><entry
553	 align="char">
554	<para>ENODEV</para>
555	</entry><entry
556	 align="char">
557	<para>Device driver not loaded/available.</para>
558	</entry>
559	 </row><row><entry
560	 align="char">
561	<para>EINTERNAL</para>
562	</entry><entry
563	 align="char">
564	<para>Internal error.</para>
565	</entry>
566	 </row><row><entry
567	 align="char">
568	<para>EBUSY</para>
569	</entry><entry
570	 align="char">
571	<para>Device or resource busy.</para>
572	</entry>
573	 </row><row><entry
574	 align="char">
575	<para>EINVAL</para>
576	</entry><entry
577	 align="char">
578	<para>Invalid argument.</para>
579	</entry>
580	 </row></tbody></tgroup></informaltable>
581	</section>
582	
583	<section id="frontend_f_close">
584	<title>close()</title>
585	<para>DESCRIPTION
586	</para>
587	<informaltable><tgroup cols="1"><tbody><row><entry
588	 align="char">
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>
592	</entry>
593	 </row></tbody></tgroup></informaltable>
594	<para>SYNOPSIS
595	</para>
596	<informaltable><tgroup cols="1"><tbody><row><entry
597	 align="char">
598	<para>int close(int fd);</para>
599	</entry>
600	 </row></tbody></tgroup></informaltable>
601	<para>PARAMETERS
602	</para>
603	<informaltable><tgroup cols="2"><tbody><row><entry
604	 align="char">
605	<para>int fd</para>
606	</entry><entry
607	 align="char">
608	<para>File descriptor returned by a previous call to open().</para>
609	</entry>
610	 </row></tbody></tgroup></informaltable>
611	<para>RETURN VALUE</para>
612	<informaltable><tgroup cols="2"><tbody><row><entry
613	 align="char">
614	<para>EBADF</para>
615	</entry><entry
616	 align="char">
617	<para>fd is not a valid open file descriptor.</para>
618	</entry>
619	 </row></tbody></tgroup></informaltable>
620	</section>
621	
622	<section id="FE_READ_STATUS">
623	<title>FE_READ_STATUS</title>
624	<para>DESCRIPTION
625	</para>
626	<informaltable><tgroup cols="1"><tbody><row><entry
627	 align="char">
628	<para>This ioctl call returns status information about the front-end. This call only
629	 requires read-only access to the device.</para>
630	</entry>
631	 </row></tbody></tgroup></informaltable>
632	<para>SYNOPSIS
633	</para>
634	<informaltable><tgroup cols="1"><tbody><row><entry
635	 align="char">
636	<para>int ioctl(int fd, int request = <link linkend="FE_READ_STATUS">FE_READ_STATUS</link>,
637	 fe_status_t &#x22C6;status);</para>
638	</entry>
639	 </row></tbody></tgroup></informaltable>
640	<para>PARAMETERS
641	</para>
642	
643	<informaltable><tgroup cols="2"><tbody><row><entry
644	 align="char">
645	<para>int fd</para>
646	</entry><entry
647	 align="char">
648	<para>File descriptor returned by a previous call to open().</para>
649	</entry>
650	 </row><row><entry
651	 align="char">
652	<para>int request</para>
653	</entry><entry
654	 align="char">
655	<para>Equals <link linkend="FE_READ_STATUS">FE_READ_STATUS</link> for this command.</para>
656	</entry>
657	 </row><row><entry
658	 align="char">
659	<para>struct fe_status_t
660	 *status</para>
661	</entry><entry
662	 align="char">
663	<para>Points to the location where the front-end status word is
664	 to be stored.</para>
665	</entry>
666	 </row></tbody></tgroup></informaltable>
667	<para>RETURN VALUE</para>
668	<informaltable><tgroup cols="2"><tbody><row><entry
669	 align="char">
670	<para>EBADF</para>
671	</entry><entry
672	 align="char">
673	<para>fd is not a valid open file descriptor.</para>
674	</entry>
675	 </row><row><entry
676	 align="char">
677	<para>EFAULT</para>
678	</entry><entry
679	 align="char">
680	<para>status points to invalid address.</para>
681	</entry>
682	 </row></tbody></tgroup></informaltable>
683	</section>
684	
685	<section id="FE_READ_BER">
686	<title>FE_READ_BER</title>
687	<para>DESCRIPTION
688	</para>
689	<informaltable><tgroup cols="1"><tbody><row><entry
690	 align="char">
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>
694	</entry>
695	 </row></tbody></tgroup></informaltable>
696	<para>SYNOPSIS
697	</para>
698	<informaltable><tgroup cols="1"><tbody><row><entry
699	 align="char">
700	<para>int ioctl(int fd, int request = <link linkend="FE_READ_BER">FE_READ_BER</link>,
701	 uint32_t &#x22C6;ber);</para>
702	</entry>
703	 </row></tbody></tgroup></informaltable>
704	<para>PARAMETERS
705	</para>
706	<informaltable><tgroup cols="2"><tbody><row><entry
707	 align="char">
708	<para>int fd</para>
709	</entry><entry
710	 align="char">
711	<para>File descriptor returned by a previous call to open().</para>
712	</entry>
713	 </row><row><entry
714	 align="char">
715	<para>int request</para>
716	</entry><entry
717	 align="char">
718	<para>Equals <link linkend="FE_READ_BER">FE_READ_BER</link> for this command.</para>
719	</entry>
720	 </row><row><entry
721	 align="char">
722	<para>uint32_t *ber</para>
723	</entry><entry
724	 align="char">
725	<para>The bit error rate is stored into *ber.</para>
726	</entry>
727	 </row></tbody></tgroup></informaltable>
728	
729	&return-value-dvb;
730	</section>
731	
732	<section id="FE_READ_SNR">
733	<title>FE_READ_SNR</title>
734	
735	<para>DESCRIPTION
736	</para>
737	<informaltable><tgroup cols="1"><tbody><row><entry
738	 align="char">
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>
741	</entry>
742	 </row></tbody></tgroup></informaltable>
743	<para>SYNOPSIS
744	</para>
745	<informaltable><tgroup cols="1"><tbody><row><entry
746	 align="char">
747	<para>int ioctl(int fd, int request = <link linkend="FE_READ_SNR">FE_READ_SNR</link>, uint16_t
748	 &#x22C6;snr);</para>
749	</entry>
750	 </row></tbody></tgroup></informaltable>
751	<para>PARAMETERS
752	</para>
753	<informaltable><tgroup cols="2"><tbody><row><entry
754	 align="char">
755	<para>int fd</para>
756	</entry><entry
757	 align="char">
758	<para>File descriptor returned by a previous call to open().</para>
759	</entry>
760	 </row><row><entry
761	 align="char">
762	<para>int request</para>
763	</entry><entry
764	 align="char">
765	<para>Equals <link linkend="FE_READ_SNR">FE_READ_SNR</link> for this command.</para>
766	</entry>
767	 </row><row><entry
768	 align="char">
769	<para>uint16_t *snr</para>
770	</entry><entry
771	 align="char">
772	<para>The signal-to-noise ratio is stored into *snr.</para>
773	</entry>
774	 </row></tbody></tgroup></informaltable>
775	
776	&return-value-dvb;
777	</section>
778	
779	<section id="FE_READ_SIGNAL_STRENGTH">
780	<title>FE_READ_SIGNAL_STRENGTH</title>
781	<para>DESCRIPTION
782	</para>
783	<informaltable><tgroup cols="1"><tbody><row><entry
784	 align="char">
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>
787	</entry>
788	 </row></tbody></tgroup></informaltable>
789	<para>SYNOPSIS
790	</para>
791	<informaltable><tgroup cols="1"><tbody><row><entry
792	 align="char">
793	<para>int ioctl( int fd, int request =
794	 <link linkend="FE_READ_SIGNAL_STRENGTH">FE_READ_SIGNAL_STRENGTH</link>, uint16_t &#x22C6;strength);</para>
795	</entry>
796	 </row></tbody></tgroup></informaltable>
797	
798	<para>PARAMETERS
799	</para>
800	<informaltable><tgroup cols="2"><tbody><row><entry
801	 align="char">
802	<para>int fd</para>
803	</entry><entry
804	 align="char">
805	<para>File descriptor returned by a previous call to open().</para>
806	</entry>
807	 </row><row><entry
808	 align="char">
809	<para>int request</para>
810	</entry><entry
811	 align="char">
812	<para>Equals <link linkend="FE_READ_SIGNAL_STRENGTH">FE_READ_SIGNAL_STRENGTH</link> for this
813	 command.</para>
814	</entry>
815	 </row><row><entry
816	 align="char">
817	<para>uint16_t *strength</para>
818	</entry><entry
819	 align="char">
820	<para>The signal strength value is stored into *strength.</para>
821	</entry>
822	 </row></tbody></tgroup></informaltable>
823	
824	&return-value-dvb;
825	</section>
826	
827	<section id="FE_READ_UNCORRECTED_BLOCKS">
828	<title>FE_READ_UNCORRECTED_BLOCKS</title>
829	<para>DESCRIPTION
830	</para>
831	<informaltable><tgroup cols="1"><tbody><row><entry
832	 align="char">
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>
837	</entry>
838	 </row><row><entry
839	 align="char">
840	<para>Note that the counter will wrap to zero after its maximum count has been
841	 reached.</para>
842	</entry>
843	 </row></tbody></tgroup></informaltable>
844	<para>SYNOPSIS
845	</para>
846	<informaltable><tgroup cols="1"><tbody><row><entry
847	 align="char">
848	<para>int ioctl( int fd, int request =
849	 <link linkend="FE_READ_UNCORRECTED_BLOCKS">FE_READ_UNCORRECTED_BLOCKS</link>, uint32_t &#x22C6;ublocks);</para>
850	</entry>
851	 </row></tbody></tgroup></informaltable>
852	<para>PARAMETERS
853	</para>
854	<informaltable><tgroup cols="2"><tbody><row><entry
855	 align="char">
856	<para>int fd</para>
857	</entry><entry
858	 align="char">
859	<para>File descriptor returned by a previous call to open().</para>
860	</entry>
861	 </row><row><entry
862	 align="char">
863	<para>int request</para>
864	</entry><entry
865	 align="char">
866	<para>Equals <link linkend="FE_READ_UNCORRECTED_BLOCKS">FE_READ_UNCORRECTED_BLOCKS</link> for this
867	 command.</para>
868	</entry>
869	 </row><row><entry
870	 align="char">
871	<para>uint32_t *ublocks</para>
872	</entry><entry
873	 align="char">
874	<para>The total number of uncorrected blocks seen by the driver
875	 so far.</para>
876	</entry>
877	 </row></tbody></tgroup></informaltable>
878	
879	&return-value-dvb;
880	</section>
881	
882	<section id="FE_SET_FRONTEND">
883	<title>FE_SET_FRONTEND</title>
884	<para>DESCRIPTION
885	</para>
886	<informaltable><tgroup cols="1"><tbody><row><entry
887	 align="char">
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>
895	</entry>
896	 </row></tbody></tgroup></informaltable>
897	
898	<para>SYNOPSIS
899	</para>
900	<informaltable><tgroup cols="1"><tbody><row><entry
901	 align="char">
902	<para>int ioctl(int fd, int request = <link linkend="FE_SET_FRONTEND">FE_SET_FRONTEND</link>,
903	 struct dvb_frontend_parameters &#x22C6;p);</para>
904	</entry>
905	 </row></tbody></tgroup></informaltable>
906	<para>PARAMETERS
907	</para>
908	<informaltable><tgroup cols="2"><tbody><row><entry
909	 align="char">
910	<para>int fd</para>
911	</entry><entry
912	 align="char">
913	<para>File descriptor returned by a previous call to open().</para>
914	</entry>
915	 </row><row><entry
916	 align="char">
917	<para>int request</para>
918	</entry><entry
919	 align="char">
920	<para>Equals <link linkend="FE_SET_FRONTEND">FE_SET_FRONTEND</link> for this command.</para>
921	</entry>
922	 </row><row><entry
923	 align="char">
924	<para>struct
925	 dvb_frontend_parameters
926	 *p</para>
927	</entry><entry
928	 align="char">
929	<para>Points to parameters for tuning operation.</para>
930	</entry>
931	 </row></tbody></tgroup></informaltable>
932	
933	&return-value-dvb;
934	<informaltable><tgroup cols="2"><tbody><row><entry
935	 align="char">
936	<para>EINVAL</para>
937	</entry><entry
938	 align="char">
939	<para>Maximum supported symbol rate reached.</para>
940	</entry>
941	</row></tbody></tgroup></informaltable>
942	</section>
943	
944	<section id="FE_GET_FRONTEND">
945	<title>FE_GET_FRONTEND</title>
946	<para>DESCRIPTION
947	</para>
948	<informaltable><tgroup cols="1"><tbody><row><entry
949	 align="char">
950	<para>This ioctl call queries the currently effective frontend parameters. For this
951	 command, read-only access to the device is sufficient.</para>
952	</entry>
953	 </row></tbody></tgroup></informaltable>
954	
955	<para>SYNOPSIS
956	</para>
957	<informaltable><tgroup cols="1"><tbody><row><entry
958	 align="char">
959	<para>int ioctl(int fd, int request = <link linkend="FE_GET_FRONTEND">FE_GET_FRONTEND</link>,
960	 struct dvb_frontend_parameters &#x22C6;p);</para>
961	</entry>
962	 </row></tbody></tgroup></informaltable>
963	
964	<para>PARAMETERS
965	</para>
966	<informaltable><tgroup cols="2"><tbody><row><entry
967	 align="char">
968	<para>int fd</para>
969	</entry><entry
970	 align="char">
971	<para>File descriptor returned by a previous call to open().</para>
972	</entry>
973	 </row><row><entry
974	 align="char">
975	<para>int request</para>
976	</entry><entry
977	 align="char">
978	<para>Equals <link linkend="FE_SET_FRONTEND">FE_SET_FRONTEND</link> for this command.</para>
979	</entry>
980	 </row><row><entry
981	 align="char">
982	<para>struct
983	 dvb_frontend_parameters
984	 *p</para>
985	</entry><entry
986	 align="char">
987	<para>Points to parameters for tuning operation.</para>
988	</entry>
989	 </row></tbody></tgroup></informaltable>
990	
991	&return-value-dvb;
992	<informaltable><tgroup cols="2"><tbody><row><entry
993	 align="char">
994	<para>EINVAL</para>
995	</entry><entry
996	 align="char">
997	<para>Maximum supported symbol rate reached.</para>
998	</entry>
999	 </row></tbody></tgroup></informaltable>
1000	
1001	</section>
1002	
1003	<section id="FE_GET_EVENT">
1004	<title>FE_GET_EVENT</title>
1005	<para>DESCRIPTION
1006	</para>
1007	<informaltable><tgroup cols="1"><tbody><row><entry
1008	 align="char">
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>
1014	</entry>
1015	 </row><row><entry
1016	 align="char">
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>
1027	</entry>
1028	 </row><row><entry
1029	 align="char">
1030	<para>For the sake of implementation simplicity, this command requires read/write
1031	 access to the device.</para>
1032	</entry>
1033	 </row></tbody></tgroup></informaltable>
1034	
1035	<para>SYNOPSIS
1036	</para>
1037	<informaltable><tgroup cols="1"><tbody><row><entry
1038	 align="char">
1039	<para>int ioctl(int fd, int request = QPSK_GET_EVENT,
1040	 struct dvb_frontend_event &#x22C6;ev);</para>
1041	</entry>
1042	 </row></tbody></tgroup></informaltable>
1043	
1044	<para>PARAMETERS
1045	</para>
1046	<informaltable><tgroup cols="2"><tbody><row><entry
1047	 align="char">
1048	<para>int fd</para>
1049	</entry><entry
1050	 align="char">
1051	<para>File descriptor returned by a previous call to open().</para>
1052	</entry>
1053	 </row><row><entry
1054	 align="char">
1055	<para>int request</para>
1056	</entry><entry
1057	 align="char">
1058	<para>Equals <link linkend="FE_GET_EVENT">FE_GET_EVENT</link> for this command.</para>
1059	</entry>
1060	 </row><row><entry
1061	 align="char">
1062	<para>struct
1063	 dvb_frontend_event
1064	 *ev</para>
1065	</entry><entry
1066	 align="char">
1067	<para>Points to the location where the event,</para>
1068	</entry>
1069	 </row><row><entry
1070	 align="char">
1071	</entry><entry
1072	 align="char">
1073	<para>if any, is to be stored.</para>
1074	</entry>
1075	 </row></tbody></tgroup></informaltable>
1076	
1077	&return-value-dvb;
1078	<informaltable><tgroup cols="2"><tbody><row><entry
1079	 align="char">
1080	<para>EWOULDBLOCK</para>
1081	</entry><entry
1082	 align="char">
1083	<para>There is no event pending, and the device is in
1084	 non-blocking mode.</para>
1085	</entry>
1086	 </row><row><entry
1087	 align="char">
1088	<para>EOVERFLOW</para>
1089	</entry><entry
1090	 align="char">
1091	<para>Overflow in event queue - one or more events were lost.</para>
1092	</entry>
1093	</row></tbody></tgroup></informaltable>
1094	</section>
1095	
1096	<section id="FE_GET_INFO">
1097	<title>FE_GET_INFO</title>
1098	<para>DESCRIPTION
1099	</para>
1100	<informaltable><tgroup cols="1"><tbody><row><entry
1101	 align="char">
1102	<para>This ioctl call returns information about the front-end. This call only requires
1103	 read-only access to the device.</para>
1104	</entry>
1105	 </row></tbody></tgroup></informaltable>
1106	<para>SYNOPSIS
1107	</para>
1108	
1109	<informaltable><tgroup cols="1"><tbody><row><entry
1110	 align="char">
1111	<para> int ioctl(int fd, int request = <link linkend="FE_GET_INFO">FE_GET_INFO</link>, struct
1112	 dvb_frontend_info &#x22C6;info);</para>
1113	</entry>
1114	 </row></tbody></tgroup></informaltable>
1115	<para>PARAMETERS
1116	</para>
1117	
1118	<informaltable><tgroup cols="2"><tbody><row><entry
1119	 align="char">
1120	<para>int fd</para>
1121	</entry><entry
1122	 align="char">
1123	<para>File descriptor returned by a previous call to open().</para>
1124	</entry>
1125	 </row><row><entry
1126	 align="char">
1127	<para>int request</para>
1128	</entry><entry
1129	 align="char">
1130	<para>Equals <link linkend="FE_GET_INFO">FE_GET_INFO</link> for this command.</para>
1131	</entry>
1132	 </row><row><entry
1133	 align="char">
1134	<para>struct
1135	 dvb_frontend_info
1136	 *info</para>
1137	</entry><entry
1138	 align="char">
1139	<para>Points to the location where the front-end information is
1140	 to be stored.</para>
1141	</entry>
1142	 </row></tbody></tgroup></informaltable>
1143	&return-value-dvb;
1144	</section>
1145	
1146	<section id="FE_DISEQC_RESET_OVERLOAD">
1147	<title>FE_DISEQC_RESET_OVERLOAD</title>
1148	<para>DESCRIPTION
1149	</para>
1150	<informaltable><tgroup cols="1"><tbody><row><entry
1151	 align="char">
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>
1156	</entry>
1157	 </row></tbody></tgroup></informaltable>
1158	
1159	<para>SYNOPSIS
1160	</para>
1161	<informaltable><tgroup cols="1"><tbody><row><entry
1162	 align="char">
1163	<para>int ioctl(int fd, int request =
1164	 <link linkend="FE_DISEQC_RESET_OVERLOAD">FE_DISEQC_RESET_OVERLOAD</link>);</para>
1165	</entry>
1166	 </row></tbody></tgroup></informaltable>
1167	<para>PARAMETERS
1168	</para>
1169	<informaltable><tgroup cols="2"><tbody><row><entry
1170	 align="char">
1171	<para>int fd</para>
1172	</entry><entry
1173	 align="char">
1174	<para>File descriptor returned by a previous call to open().</para>
1175	</entry>
1176	 </row><row><entry
1177	 align="char">
1178	<para>int request</para>
1179	</entry><entry
1180	 align="char">
1181	<para>Equals <link linkend="FE_DISEQC_RESET_OVERLOAD">FE_DISEQC_RESET_OVERLOAD</link> for this
1182	 command.</para>
1183	</entry>
1184	 </row></tbody></tgroup></informaltable>
1185	
1186	&return-value-dvb;
1187	</section>
1188	
1189	<section id="FE_DISEQC_SEND_MASTER_CMD">
1190	<title>FE_DISEQC_SEND_MASTER_CMD</title>
1191	<para>DESCRIPTION
1192	</para>
1193	<informaltable><tgroup cols="1"><tbody><row><entry
1194	 align="char">
1195	<para>This ioctl call is used to send a a DiSEqC command.</para>
1196	</entry>
1197	 </row></tbody></tgroup></informaltable>
1198	<para>SYNOPSIS
1199	</para>
1200	<informaltable><tgroup cols="1"><tbody><row><entry
1201	 align="char">
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 &#x22C6;cmd);</para>
1205	</entry>
1206	 </row></tbody></tgroup></informaltable>
1207	
1208	<para>PARAMETERS
1209	</para>
1210	<informaltable><tgroup cols="2"><tbody><row><entry
1211	 align="char">
1212	<para>int fd</para>
1213	</entry><entry
1214	 align="char">
1215	<para>File descriptor returned by a previous call to open().</para>
1216	</entry>
1217	 </row><row><entry
1218	 align="char">
1219	<para>int request</para>
1220	</entry><entry
1221	 align="char">
1222	<para>Equals <link linkend="FE_DISEQC_SEND_MASTER_CMD">FE_DISEQC_SEND_MASTER_CMD</link> for this
1223	 command.</para>
1224	</entry>
1225	 </row><row><entry
1226	 align="char">
1227	<para>struct
1228	 dvb_diseqc_master_cmd
1229	 *cmd</para>
1230	</entry><entry
1231	 align="char">
1232	<para>Pointer to the command to be transmitted.</para>
1233	</entry>
1234	 </row></tbody></tgroup></informaltable>
1235	
1236	&return-value-dvb;
1237	</section>
1238	
1239	<section id="FE_DISEQC_RECV_SLAVE_REPLY">
1240	<title>FE_DISEQC_RECV_SLAVE_REPLY</title>
1241	<para>DESCRIPTION
1242	</para>
1243	<informaltable><tgroup cols="1"><tbody><row><entry
1244	 align="char">
1245	<para>This ioctl call is used to receive reply to a DiSEqC 2.0 command.</para>
1246	</entry>
1247	 </row></tbody></tgroup></informaltable>
1248	
1249	<para>SYNOPSIS
1250	</para>
1251	<informaltable><tgroup cols="1"><tbody><row><entry
1252	 align="char">
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 &#x22C6;reply);</para>
1256	</entry>
1257	 </row></tbody></tgroup></informaltable>
1258	
1259	<para>PARAMETERS
1260	</para>
1261	<informaltable><tgroup cols="2"><tbody><row><entry
1262	 align="char">
1263	<para>int fd</para>
1264	</entry><entry
1265	 align="char">
1266	<para>File descriptor returned by a previous call to open().</para>
1267	</entry>
1268	 </row><row><entry
1269	 align="char">
1270	<para>int request</para>
1271	</entry><entry
1272	 align="char">
1273	<para>Equals <link linkend="FE_DISEQC_RECV_SLAVE_REPLY">FE_DISEQC_RECV_SLAVE_REPLY</link> for this
1274	 command.</para>
1275	</entry>
1276	 </row><row><entry
1277	 align="char">
1278	<para>struct
1279	 dvb_diseqc_slave_reply
1280	 *reply</para>
1281	</entry><entry
1282	 align="char">
1283	<para>Pointer to the command to be received.</para>
1284	</entry>
1285	 </row></tbody></tgroup></informaltable>
1286	&return-value-dvb;
1287	</section>
1288	
1289	<section id="FE_DISEQC_SEND_BURST">
1290	<title>FE_DISEQC_SEND_BURST</title>
1291	<para>DESCRIPTION
1292	</para>
1293	<informaltable><tgroup cols="1"><tbody><row><entry
1294	 align="char">
1295	<para>This ioctl call is used to send a 22KHz tone burst.</para>
1296	</entry>
1297	 </row></tbody></tgroup></informaltable>
1298	
1299	<para>SYNOPSIS
1300	</para>
1301	<informaltable><tgroup cols="1"><tbody><row><entry
1302	 align="char">
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>
1305	</entry>
1306	 </row></tbody></tgroup></informaltable>
1307	
1308	<para>PARAMETERS
1309	</para>
1310	<informaltable><tgroup cols="2"><tbody><row><entry
1311	 align="char">
1312	<para>int fd</para>
1313	</entry><entry
1314	 align="char">
1315	<para>File descriptor returned by a previous call to open().</para>
1316	</entry>
1317	 </row><row><entry
1318	 align="char">
1319	<para>int request</para>
1320	</entry><entry
1321	 align="char">
1322	<para>Equals <link linkend="FE_DISEQC_SEND_BURST">FE_DISEQC_SEND_BURST</link> for this command.</para>
1323	</entry>
1324	 </row><row><entry
1325	 align="char">
1326	<para>fe_sec_mini_cmd_t
1327	 burst</para>
1328	</entry><entry
1329	 align="char">
1330	<para>burst A or B.</para>
1331	</entry>
1332	 </row></tbody></tgroup></informaltable>
1333	
1334	&return-value-dvb;
1335	</section>
1336	
1337	<section id="FE_SET_TONE">
1338	<title>FE_SET_TONE</title>
1339	<para>DESCRIPTION
1340	</para>
1341	<informaltable><tgroup cols="1"><tbody><row><entry
1342	 align="char">
1343	<para>This call is used to set the generation of the continuous 22kHz tone. This call
1344	 requires read/write permissions.</para>
1345	</entry>
1346	 </row></tbody></tgroup></informaltable>
1347	<para>SYNOPSIS
1348	</para>
1349	<informaltable><tgroup cols="1"><tbody><row><entry
1350	 align="char">
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>
1353	</entry>
1354	 </row></tbody></tgroup></informaltable>
1355	<para>PARAMETERS
1356	</para>
1357	<informaltable><tgroup cols="2"><tbody><row><entry
1358	 align="char">
1359	<para>int fd</para>
1360	</entry><entry
1361	 align="char">
1362	<para>File descriptor returned by a previous call to open().</para>
1363	</entry>
1364	 </row><row><entry
1365	 align="char">
1366	<para>int request</para>
1367	</entry><entry
1368	 align="char">
1369	<para>Equals <link linkend="FE_SET_TONE">FE_SET_TONE</link> for this command.</para>
1370	</entry>
1371	 </row><row><entry
1372	 align="char">
1373	<para>fe_sec_tone_mode_t
1374	 tone</para>
1375	</entry><entry
1376	 align="char">
1377	<para>The requested tone generation mode (on/off).</para>
1378	</entry>
1379	 </row></tbody></tgroup></informaltable>
1380	&return-value-dvb;
1381	</section>
1382	
1383	<section id="FE_SET_VOLTAGE">
1384	<title>FE_SET_VOLTAGE</title>
1385	<para>DESCRIPTION
1386	</para>
1387	<informaltable><tgroup cols="1"><tbody><row><entry
1388	 align="char">
1389	<para>This call is used to set the bus voltage. This call requires read/write
1390	 permissions.</para>
1391	</entry>
1392	 </row></tbody></tgroup></informaltable>
1393	<para>SYNOPSIS
1394	</para>
1395	<informaltable><tgroup cols="1"><tbody><row><entry
1396	 align="char">
1397	<para>int ioctl(int fd, int request = <link linkend="FE_SET_VOLTAGE">FE_SET_VOLTAGE</link>,
1398	 fe_sec_voltage_t voltage);</para>
1399	</entry>
1400	 </row></tbody></tgroup></informaltable>
1401	
1402	<para>PARAMETERS
1403	</para>
1404	<informaltable><tgroup cols="2"><tbody><row><entry
1405	 align="char">
1406	<para>int fd</para>
1407	</entry><entry
1408	 align="char">
1409	<para>File descriptor returned by a previous call to open().</para>
1410	</entry>
1411	 </row><row><entry
1412	 align="char">
1413	<para>int request</para>
1414	</entry><entry
1415	 align="char">
1416	<para>Equals <link linkend="FE_SET_VOLTAGE">FE_SET_VOLTAGE</link> for this command.</para>
1417	</entry>
1418	 </row><row><entry
1419	 align="char">
1420	<para>fe_sec_voltage_t
1421	 voltage</para>
1422	</entry><entry
1423	 align="char">
1424	<para>The requested bus voltage.</para>
1425	</entry>
1426	 </row></tbody></tgroup></informaltable>
1427	
1428	&return-value-dvb;
1429	</section>
1430	
1431	<section id="FE_ENABLE_HIGH_LNB_VOLTAGE">
1432	<title>FE_ENABLE_HIGH_LNB_VOLTAGE</title>
1433	<para>DESCRIPTION
1434	</para>
1435	<informaltable><tgroup cols="1"><tbody><row><entry
1436	 align="char">
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>
1440	</entry>
1441	 </row></tbody></tgroup></informaltable>
1442	
1443	<para>SYNOPSIS
1444	</para>
1445	<informaltable><tgroup cols="1"><tbody><row><entry
1446	 align="char">
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>
1449	</entry>
1450	 </row></tbody></tgroup></informaltable>
1451	
1452	<para>PARAMETERS
1453	</para>
1454	<informaltable><tgroup cols="2"><tbody><row><entry
1455	 align="char">
1456	<para>int fd</para>
1457	</entry><entry
1458	 align="char">
1459	<para>File descriptor returned by a previous call to open().</para>
1460	</entry>
1461	 </row><row><entry
1462	 align="char">
1463	<para>int request</para>
1464	</entry><entry
1465	 align="char">
1466	<para>Equals <link linkend="FE_SET_VOLTAGE">FE_SET_VOLTAGE</link> for this command.</para>
1467	</entry>
1468	 </row><row><entry
1469	 align="char">
1470	<para>int high</para>
1471	</entry><entry
1472	 align="char">
1473	<para>The requested bus voltage.</para>
1474	</entry>
1475	 </row></tbody></tgroup></informaltable>
1476	
1477	&return-value-dvb;
1478	</section>
1479	
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>
1486	</entry>
1487	</row></tbody></tgroup></informaltable>
1488	
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>
1494	</entry>
1495	</row></tbody></tgroup></informaltable>
1496	
1497	<para>PARAMETERS</para>
1498	<informaltable><tgroup cols="2"><tbody><row>
1499	<entry align="char">
1500		<para>unsigned int flags</para>
1501	</entry>
1502	<entry align="char">
1503	<para>
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.
1505	</para>
1506	</entry>
1507	 </row></tbody></tgroup></informaltable>
1508	
1509	&return-value-dvb;
1510	</section>
1511	
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>
1520	</entry>
1521	</row></tbody></tgroup></informaltable>
1522	
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>
1528	</entry>
1529	</row></tbody></tgroup></informaltable>
1530	
1531	<para>PARAMETERS</para>
1532	<informaltable><tgroup cols="2"><tbody><row>
1533	<entry align="char">
1534		<para>unsigned long cmd</para>
1535	</entry>
1536	<entry align="char">
1537	<para>
1538	sends the specified raw cmd to the dish via DISEqC.
1539	</para>
1540	</entry>
1541	 </row></tbody></tgroup></informaltable>
1542	
1543	&return-value-dvb;
1544	</section>
1545	
1546	</section>
1547	
1548	&sub-dvbproperty;
Hide Line Numbers
About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Information is copyright its respective author. All material is available from the Linux Kernel Source distributed under a GPL License. This page is provided as a free service by mjmwired.net.