summaryrefslogtreecommitdiff
path: root/drivers/media/dvb-core/demux.h
blob: f854309ba8a5a385d9eec0fd9fca5e10f5177b9a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
/*
 * demux.h
 *
 * The Kernel Digital TV Demux kABI defines a driver-internal interface for
 * registering low-level, hardware specific driver to a hardware independent
 * demux layer.
 *
 * Copyright (c) 2002 Convergence GmbH
 *
 * based on code:
 * Copyright (c) 2000 Nokia Research Center
 *                    Tampere, FINLAND
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#ifndef __DEMUX_H
#define __DEMUX_H

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/time.h>
#include <linux/dvb/dmx.h>

/*
 * Common definitions
 */

/*
 * DMX_MAX_FILTER_SIZE: Maximum length (in bytes) of a section/PES filter.
 */

#ifndef DMX_MAX_FILTER_SIZE
#define DMX_MAX_FILTER_SIZE 18
#endif

/*
 * DMX_MAX_SECFEED_SIZE: Maximum length (in bytes) of a private section feed
 * filter.
 */

#ifndef DMX_MAX_SECTION_SIZE
#define DMX_MAX_SECTION_SIZE 4096
#endif
#ifndef DMX_MAX_SECFEED_SIZE
#define DMX_MAX_SECFEED_SIZE (DMX_MAX_SECTION_SIZE + 188)
#endif

/*
 * TS packet reception
 */

/**
 * enum ts_filter_type - filter type bitmap for dmx_ts_feed.set\(\)
 *
 * @TS_PACKET:		Send TS packets (188 bytes) to callback (default).
 * @TS_PAYLOAD_ONLY:	In case TS_PACKET is set, only send the TS payload
 *			(<=184 bytes per packet) to callback
 * @TS_DECODER:		Send stream to built-in decoder (if present).
 * @TS_DEMUX:		In case TS_PACKET is set, send the TS to the demux
 *			device, not to the dvr device
 */
enum ts_filter_type {
	TS_PACKET = 1,
	TS_PAYLOAD_ONLY = 2,
	TS_DECODER = 4,
	TS_DEMUX = 8,
};

/**
 * struct dmx_ts_feed - Structure that contains a TS feed filter
 *
 * @is_filtering:	Set to non-zero when filtering in progress
 * @parent:		pointer to struct dmx_demux
 * @priv:		pointer to private data of the API client
 * @set:		sets the TS filter
 * @start_filtering:	starts TS filtering
 * @stop_filtering:	stops TS filtering
 *
 * A TS feed is typically mapped to a hardware PID filter on the demux chip.
 * Using this API, the client can set the filtering properties to start/stop
 * filtering TS packets on a particular TS feed.
 */
struct dmx_ts_feed {
	int is_filtering;
	struct dmx_demux *parent;
	void *priv;
	int (*set)(struct dmx_ts_feed *feed,
		   u16 pid,
		   int type,
		   enum dmx_ts_pes pes_type,
		   ktime_t timeout);
	int (*start_filtering)(struct dmx_ts_feed *feed);
	int (*stop_filtering)(struct dmx_ts_feed *feed);
};

/*
 * Section reception
 */

/**
 * struct dmx_section_filter - Structure that describes a section filter
 *
 * @filter_value: Contains up to 16 bytes (128 bits) of the TS section header
 *		  that will be matched by the section filter
 * @filter_mask:  Contains a 16 bytes (128 bits) filter mask with the bits
 *		  specified by @filter_value that will be used on the filter
 *		  match logic.
 * @filter_mode:  Contains a 16 bytes (128 bits) filter mode.
 * @parent:	  Pointer to struct dmx_section_feed.
 * @priv:	  Pointer to private data of the API client.
 *
 *
 * The @filter_mask controls which bits of @filter_value are compared with
 * the section headers/payload. On a binary value of 1 in filter_mask, the
 * corresponding bits are compared. The filter only accepts sections that are
 * equal to filter_value in all the tested bit positions.
 */
struct dmx_section_filter {
	u8 filter_value[DMX_MAX_FILTER_SIZE];
	u8 filter_mask[DMX_MAX_FILTER_SIZE];
	u8 filter_mode[DMX_MAX_FILTER_SIZE];
	struct dmx_section_feed *parent; /* Back-pointer */
	void *priv; /* Pointer to private data of the API client */
};

/**
 * struct dmx_section_feed - Structure that contains a section feed filter
 *
 * @is_filtering:	Set to non-zero when filtering in progress
 * @parent:		pointer to struct dmx_demux
 * @priv:		pointer to private data of the API client
 * @check_crc:		If non-zero, check the CRC values of filtered sections.
 * @set:		sets the section filter
 * @allocate_filter:	This function is used to allocate a section filter on
 *			the demux. It should only be called when no filtering
 *			is in progress on this section feed. If a filter cannot
 *			be allocated, the function fails with -ENOSPC.
 * @release_filter:	This function releases all the resources of a
 *			previously allocated section filter. The function
 *			should not be called while filtering is in progress
 *			on this section feed. After calling this function,
 *			the caller should not try to dereference the filter
 *			pointer.
 * @start_filtering:	starts section filtering
 * @stop_filtering:	stops section filtering
 *
 * A TS feed is typically mapped to a hardware PID filter on the demux chip.
 * Using this API, the client can set the filtering properties to start/stop
 * filtering TS packets on a particular TS feed.
 */
struct dmx_section_feed {
	int is_filtering;
	struct dmx_demux *parent;
	void *priv;

	int check_crc;

	/* private: Used internally at dvb_demux.c */
	u32 crc_val;

	u8 *secbuf;
	u8 secbuf_base[DMX_MAX_SECFEED_SIZE];
	u16 secbufp, seclen, tsfeedp;

	/* public: */
	int (*set)(struct dmx_section_feed *feed,
		   u16 pid,
		   int check_crc);
	int (*allocate_filter)(struct dmx_section_feed *feed,
			       struct dmx_section_filter **filter);
	int (*release_filter)(struct dmx_section_feed *feed,
			      struct dmx_section_filter *filter);
	int (*start_filtering)(struct dmx_section_feed *feed);
	int (*stop_filtering)(struct dmx_section_feed *feed);
};

/**
 * typedef dmx_ts_cb - DVB demux TS filter callback function prototype
 *
 * @buffer1:		Pointer to the start of the filtered TS packets.
 * @buffer1_length:	Length of the TS data in buffer1.
 * @buffer2:		Pointer to the tail of the filtered TS packets, or NULL.
 * @buffer2_length:	Length of the TS data in buffer2.
 * @source:		Indicates which TS feed is the source of the callback.
 *
 * This function callback prototype, provided by the client of the demux API,
 * is called from the demux code. The function is only called when filtering
 * on a TS feed has been enabled using the start_filtering\(\) function at
 * the &dmx_demux.
 * Any TS packets that match the filter settings are copied to a circular
 * buffer. The filtered TS packets are delivered to the client using this
 * callback function.
 * It is expected that the @buffer1 and @buffer2 callback parameters point to
 * addresses within the circular buffer, but other implementations are also
 * possible. Note that the called party should not try to free the memory
 * the @buffer1 and @buffer2 parameters point to.
 *
 * When this function is called, the @buffer1 parameter typically points to
 * the start of the first undelivered TS packet within a circular buffer.
 * The @buffer2 buffer parameter is normally NULL, except when the received
 * TS packets have crossed the last address of the circular buffer and
 * ”wrapped” to the beginning of the buffer. In the latter case the @buffer1
 * parameter would contain an address within the circular buffer, while the
 * @buffer2 parameter would contain the first address of the circular buffer.
 * The number of bytes delivered with this function (i.e. @buffer1_length +
 * @buffer2_length) is usually equal to the value of callback_length parameter
 * given in the set() function, with one exception: if a timeout occurs before
 * receiving callback_length bytes of TS data, any undelivered packets are
 * immediately delivered to the client by calling this function. The timeout
 * duration is controlled by the set() function in the TS Feed API.
 *
 * If a TS packet is received with errors that could not be fixed by the
 * TS-level forward error correction (FEC), the Transport_error_indicator
 * flag of the TS packet header should be set. The TS packet should not be
 * discarded, as the error can possibly be corrected by a higher layer
 * protocol. If the called party is slow in processing the callback, it
 * is possible that the circular buffer eventually fills up. If this happens,
 * the demux driver should discard any TS packets received while the buffer
 * is full and return -EOVERFLOW.
 *
 * The type of data returned to the callback can be selected by the
 * &dmx_ts_feed.@set function. The type parameter decides if the raw
 * TS packet (TS_PACKET) or just the payload (TS_PACKET|TS_PAYLOAD_ONLY)
 * should be returned. If additionally the TS_DECODER bit is set the stream
 * will also be sent to the hardware MPEG decoder.
 *
 * Return:
 *
 * - 0, on success;
 *
 * - -EOVERFLOW, on buffer overflow.
 */
typedef int (*dmx_ts_cb)(const u8 *buffer1,
			 size_t buffer1_length,
			 const u8 *buffer2,
			 size_t buffer2_length,
			 struct dmx_ts_feed *source);

/**
 * typedef dmx_section_cb - DVB demux TS filter callback function prototype
 *
 * @buffer1:		Pointer to the start of the filtered section, e.g.
 *			within the circular buffer of the demux driver.
 * @buffer1_len:	Length of the filtered section data in @buffer1,
 *			including headers and CRC.
 * @buffer2:		Pointer to the tail of the filtered section data,
 *			or NULL. Useful to handle the wrapping of a
 *			circular buffer.
 * @buffer2_len:	Length of the filtered section data in @buffer2,
 *			including headers and CRC.
 * @source:		Indicates which section feed is the source of the
 *			callback.
 *
 * This function callback prototype, provided by the client of the demux API,
 * is called from the demux code. The function is only called when
 * filtering of sections has been enabled using the function
 * &dmx_ts_feed.@start_filtering. When the demux driver has received a
 * complete section that matches at least one section filter, the client
 * is notified via this callback function. Normally this function is called
 * for each received section; however, it is also possible to deliver
 * multiple sections with one callback, for example when the system load
 * is high. If an error occurs while receiving a section, this
 * function should be called with the corresponding error type set in the
 * success field, whether or not there is data to deliver. The Section Feed
 * implementation should maintain a circular buffer for received sections.
 * However, this is not necessary if the Section Feed API is implemented as
 * a client of the TS Feed API, because the TS Feed implementation then
 * buffers the received data. The size of the circular buffer can be
 * configured using the &dmx_ts_feed.@set function in the Section Feed API.
 * If there is no room in the circular buffer when a new section is received,
 * the section must be discarded. If this happens, the value of the success
 * parameter should be DMX_OVERRUN_ERROR on the next callback.
 */
typedef int (*dmx_section_cb)(const u8 *buffer1,
			      size_t buffer1_len,
			      const u8 *buffer2,
			      size_t buffer2_len,
			      struct dmx_section_filter *source);

/*
 * DVB Front-End
 */

/**
 * enum dmx_frontend_source - Used to identify the type of frontend
 *
 * @DMX_MEMORY_FE:	The source of the demux is memory. It means that
 *			the MPEG-TS to be filtered comes from userspace,
 *			via write() syscall.
 *
 * @DMX_FRONTEND_0:	The source of the demux is a frontend connected
 *			to the demux.
 */
enum dmx_frontend_source {
	DMX_MEMORY_FE,
	DMX_FRONTEND_0,
};

/**
 * struct dmx_frontend - Structure that lists the frontends associated with
 *			 a demux
 *
 * @connectivity_list:	List of front-ends that can be connected to a
 *			particular demux;
 * @source:		Type of the frontend.
 *
 * FIXME: this structure should likely be replaced soon by some
 *	media-controller based logic.
 */
struct dmx_frontend {
	struct list_head connectivity_list;
	enum dmx_frontend_source source;
};

/*
 * MPEG-2 TS Demux
 */

/**
 * enum dmx_demux_caps - MPEG-2 TS Demux capabilities bitmap
 *
 * @DMX_TS_FILTERING:		set if TS filtering is supported;
 * @DMX_SECTION_FILTERING:	set if section filtering is supported;
 * @DMX_MEMORY_BASED_FILTERING:	set if write() available.
 *
 * Those flags are OR'ed in the &dmx_demux.capabilities field
 */
enum dmx_demux_caps {
	DMX_TS_FILTERING = 1,
	DMX_SECTION_FILTERING = 4,
	DMX_MEMORY_BASED_FILTERING = 8,
};

/*
 * Demux resource type identifier.
 */

/**
 * DMX_FE_ENTRY - Casts elements in the list of registered
 *		  front-ends from the generic type struct list_head
 *		  to the type * struct dmx_frontend
 *
 * @list: list of struct dmx_frontend
 */
#define DMX_FE_ENTRY(list) \
	list_entry(list, struct dmx_frontend, connectivity_list)

/**
 * struct dmx_demux - Structure that contains the demux capabilities and
 *		      callbacks.
 *
 * @capabilities: Bitfield of capability flags.
 *
 * @frontend: Front-end connected to the demux
 *
 * @priv: Pointer to private data of the API client
 *
 * @open: This function reserves the demux for use by the caller and, if
 *	necessary, initializes the demux. When the demux is no longer needed,
 *	the function @close should be called. It should be possible for
 *	multiple clients to access the demux at the same time. Thus, the
 *	function implementation should increment the demux usage count when
 *	@open is called and decrement it when @close is called.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	It returns:
 *	0 on success;
 *	-EUSERS, if maximum usage count was reached;
 *	-EINVAL, on bad parameter.
 *
 * @close: This function reserves the demux for use by the caller and, if
 *	necessary, initializes the demux. When the demux is no longer needed,
 *	the function @close should be called. It should be possible for
 *	multiple clients to access the demux at the same time. Thus, the
 *	function implementation should increment the demux usage count when
 *	@open is called and decrement it when @close is called.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	It returns:
 *	0 on success;
 *	-ENODEV, if demux was not in use (e. g. no users);
 *	-EINVAL, on bad parameter.
 *
 * @write: This function provides the demux driver with a memory buffer
 *	containing TS packets. Instead of receiving TS packets from the DVB
 *	front-end, the demux driver software will read packets from memory.
 *	Any clients of this demux with active TS, PES or Section filters will
 *	receive filtered data via the Demux callback API (see 0). The function
 *	returns when all the data in the buffer has been consumed by the demux.
 *	Demux hardware typically cannot read TS from memory. If this is the
 *	case, memory-based filtering has to be implemented entirely in software.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	The @buf function parameter contains a pointer to the TS data in
 *	kernel-space memory.
 *	The @count function parameter contains the length of the TS data.
 *	It returns:
 *	0 on success;
 *	-ERESTARTSYS, if mutex lock was interrupted;
 *	-EINTR, if a signal handling is pending;
 *	-ENODEV, if demux was removed;
 *	-EINVAL, on bad parameter.
 *
 * @allocate_ts_feed: Allocates a new TS feed, which is used to filter the TS
 *	packets carrying a certain PID. The TS feed normally corresponds to a
 *	hardware PID filter on the demux chip.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	The @feed function parameter contains a pointer to the TS feed API and
 *	instance data.
 *	The @callback function parameter contains a pointer to the callback
 *	function for passing received TS packet.
 *	It returns:
 *	0 on success;
 *	-ERESTARTSYS, if mutex lock was interrupted;
 *	-EBUSY, if no more TS feeds is available;
 *	-EINVAL, on bad parameter.
 *
 * @release_ts_feed: Releases the resources allocated with @allocate_ts_feed.
 *	Any filtering in progress on the TS feed should be stopped before
 *	calling this function.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	The @feed function parameter contains a pointer to the TS feed API and
 *	instance data.
 *	It returns:
 *	0 on success;
 *	-EINVAL on bad parameter.
 *
 * @allocate_section_feed: Allocates a new section feed, i.e. a demux resource
 *	for filtering and receiving sections. On platforms with hardware
 *	support for section filtering, a section feed is directly mapped to
 *	the demux HW. On other platforms, TS packets are first PID filtered in
 *	hardware and a hardware section filter then emulated in software. The
 *	caller obtains an API pointer of type dmx_section_feed_t as an out
 *	parameter. Using this API the caller can set filtering parameters and
 *	start receiving sections.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	The @feed function parameter contains a pointer to the TS feed API and
 *	instance data.
 *	The @callback function parameter contains a pointer to the callback
 *	function for passing received TS packet.
 *	It returns:
 *	0 on success;
 *	-EBUSY, if no more TS feeds is available;
 *	-EINVAL, on bad parameter.
 *
 * @release_section_feed: Releases the resources allocated with
 *	@allocate_section_feed, including allocated filters. Any filtering in
 *	progress on the section feed should be stopped before calling this
 *	function.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	The @feed function parameter contains a pointer to the TS feed API and
 *	instance data.
 *	It returns:
 *	0 on success;
 *	-EINVAL, on bad parameter.
 *
 * @add_frontend: Registers a connectivity between a demux and a front-end,
 *	i.e., indicates that the demux can be connected via a call to
 *	@connect_frontend to use the given front-end as a TS source. The
 *	client of this function has to allocate dynamic or static memory for
 *	the frontend structure and initialize its fields before calling this
 *	function. This function is normally called during the driver
 *	initialization. The caller must not free the memory of the frontend
 *	struct before successfully calling @remove_frontend.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	The @frontend function parameter contains a pointer to the front-end
 *	instance data.
 *	It returns:
 *	0 on success;
 *	-EINVAL, on bad parameter.
 *
 * @remove_frontend: Indicates that the given front-end, registered by a call
 *	to @add_frontend, can no longer be connected as a TS source by this
 *	demux. The function should be called when a front-end driver or a demux
 *	driver is removed from the system. If the front-end is in use, the
 *	function fails with the return value of -EBUSY. After successfully
 *	calling this function, the caller can free the memory of the frontend
 *	struct if it was dynamically allocated before the @add_frontend
 *	operation.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	The @frontend function parameter contains a pointer to the front-end
 *	instance data.
 *	It returns:
 *	0 on success;
 *	-ENODEV, if the front-end was not found,
 *	-EINVAL, on bad parameter.
 *
 * @get_frontends: Provides the APIs of the front-ends that have been
 *	registered for this demux. Any of the front-ends obtained with this
 *	call can be used as a parameter for @connect_frontend. The include
 *	file demux.h contains the macro DMX_FE_ENTRY() for converting an
 *	element of the generic type struct &list_head * to the type
 *	struct &dmx_frontend *. The caller must not free the memory of any of
 *	the elements obtained via this function call.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	It returns a struct list_head pointer to the list of front-end
 *	interfaces, or NULL in the case of an empty list.
 *
 * @connect_frontend: Connects the TS output of the front-end to the input of
 *	the demux. A demux can only be connected to a front-end registered to
 *	the demux with the function @add_frontend. It may or may not be
 *	possible to connect multiple demuxes to the same front-end, depending
 *	on the capabilities of the HW platform. When not used, the front-end
 *	should be released by calling @disconnect_frontend.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	The @frontend function parameter contains a pointer to the front-end
 *	instance data.
 *	It returns:
 *	0 on success;
 *	-EINVAL, on bad parameter.
 *
 * @disconnect_frontend: Disconnects the demux and a front-end previously
 *	connected by a @connect_frontend call.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	It returns:
 *	0 on success;
 *	-EINVAL on bad parameter.
 *
 * @get_pes_pids: Get the PIDs for DMX_PES_AUDIO0, DMX_PES_VIDEO0,
 *	DMX_PES_TELETEXT0, DMX_PES_SUBTITLE0 and DMX_PES_PCR0.
 *	The @demux function parameter contains a pointer to the demux API and
 *	instance data.
 *	The @pids function parameter contains an array with five u16 elements
 *	where the PIDs will be stored.
 *	It returns:
 *	0 on success;
 *	-EINVAL on bad parameter.
 */
struct dmx_demux {
	enum dmx_demux_caps capabilities;
	struct dmx_frontend *frontend;
	void *priv;
	int (*open)(struct dmx_demux *demux);
	int (*close)(struct dmx_demux *demux);
	int (*write)(struct dmx_demux *demux, const char __user *buf,
		     size_t count);
	int (*allocate_ts_feed)(struct dmx_demux *demux,
				struct dmx_ts_feed **feed,
				dmx_ts_cb callback);
	int (*release_ts_feed)(struct dmx_demux *demux,
			       struct dmx_ts_feed *feed);
	int (*allocate_section_feed)(struct dmx_demux *demux,
				     struct dmx_section_feed **feed,
				     dmx_section_cb callback);
	int (*release_section_feed)(struct dmx_demux *demux,
				    struct dmx_section_feed *feed);
	int (*add_frontend)(struct dmx_demux *demux,
			    struct dmx_frontend *frontend);
	int (*remove_frontend)(struct dmx_demux *demux,
			       struct dmx_frontend *frontend);
	struct list_head *(*get_frontends)(struct dmx_demux *demux);
	int (*connect_frontend)(struct dmx_demux *demux,
				struct dmx_frontend *frontend);
	int (*disconnect_frontend)(struct dmx_demux *demux);

	int (*get_pes_pids)(struct dmx_demux *demux, u16 *pids);

	/* private: */

	/*
	 * Only used at av7110, to read some data from firmware.
	 * As this was never documented, we have no clue about what's
	 * there, and its usage on other drivers aren't encouraged.
	 */
	int (*get_stc)(struct dmx_demux *demux, unsigned int num,
		       u64 *stc, unsigned int *base);
};

#endif /* #ifndef __DEMUX_H */