1 /*
2  * dvb_demux.h: DVB kernel demux API
3  *
4  * Copyright (C) 2000-2001 Marcus Metzler & Ralph Metzler
5  *                         for convergence integrated media GmbH
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public License
9  * as published by the Free Software Foundation; either version 2.1
10  * of the License, or (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  */
18 
19 #ifndef _DVB_DEMUX_H_
20 #define _DVB_DEMUX_H_
21 
22 #include <linux/time.h>
23 #include <linux/timer.h>
24 #include <linux/spinlock.h>
25 #include <linux/mutex.h>
26 
27 #include <media/demux.h>
28 
29 /**
30  * enum dvb_dmx_filter_type - type of demux feed.
31  *
32  * @DMX_TYPE_TS:	feed is in TS mode.
33  * @DMX_TYPE_SEC:	feed is in Section mode.
34  */
35 enum dvb_dmx_filter_type {
36 	DMX_TYPE_TS,
37 	DMX_TYPE_SEC,
38 };
39 
40 /**
41  * enum dvb_dmx_state - state machine for a demux filter.
42  *
43  * @DMX_STATE_FREE:		indicates that the filter is freed.
44  * @DMX_STATE_ALLOCATED:	indicates that the filter was allocated
45  *				to be used.
46  * @DMX_STATE_READY:		indicates that the filter is ready
47  *				to be used.
48  * @DMX_STATE_GO:		indicates that the filter is running.
49  */
50 enum dvb_dmx_state {
51 	DMX_STATE_FREE,
52 	DMX_STATE_ALLOCATED,
53 	DMX_STATE_READY,
54 	DMX_STATE_GO,
55 };
56 
57 #define DVB_DEMUX_MASK_MAX 18
58 
59 #define MAX_PID 0x1fff
60 
61 #define SPEED_PKTS_INTERVAL 50000
62 
63 /**
64  * struct dvb_demux_filter - Describes a DVB demux section filter.
65  *
66  * @filter:		Section filter as defined by &struct dmx_section_filter.
67  * @maskandmode:	logical ``and`` bit mask.
68  * @maskandnotmode:	logical ``and not`` bit mask.
69  * @doneq:		flag that indicates when a filter is ready.
70  * @next:		pointer to the next section filter.
71  * @feed:		&struct dvb_demux_feed pointer.
72  * @index:		index of the used demux filter.
73  * @state:		state of the filter as described by &enum dvb_dmx_state.
74  * @type:		type of the filter as described
75  *			by &enum dvb_dmx_filter_type.
76  */
77 
78 struct dvb_demux_filter {
79 	struct dmx_section_filter filter;
80 	u8 maskandmode[DMX_MAX_FILTER_SIZE];
81 	u8 maskandnotmode[DMX_MAX_FILTER_SIZE];
82 	bool doneq;
83 
84 	struct dvb_demux_filter *next;
85 	struct dvb_demux_feed *feed;
86 	int index;
87 	enum dvb_dmx_state state;
88 	enum dvb_dmx_filter_type type;
89 
90 	/* private: used only by av7110 */
91 	u16 hw_handle;
92 };
93 
94 /**
95  * struct dvb_demux_feed - describes a DVB field
96  *
97  * @feed:	a union describing a digital TV feed.
98  *		Depending on the feed type, it can be either
99  *		@feed.ts or @feed.sec.
100  * @feed.ts:	a &struct dmx_ts_feed pointer.
101  *		For TS feed only.
102  * @feed.sec:	a &struct dmx_section_feed pointer.
103  *		For section feed only.
104  * @cb:		a union describing digital TV callbacks.
105  *		Depending on the feed type, it can be either
106  *		@cb.ts or @cb.sec.
107  * @cb.ts:	a dmx_ts_cb() calback function pointer.
108  *		For TS feed only.
109  * @cb.sec:	a dmx_section_cb() callback function pointer.
110  *		For section feed only.
111  * @demux:	pointer to &struct dvb_demux.
112  * @priv:	private data that can optionally be used by a DVB driver.
113  * @type:	type of the filter, as defined by &enum dvb_dmx_filter_type.
114  * @state:	state of the filter as defined by &enum dvb_dmx_state.
115  * @pid:	PID to be filtered.
116  * @timeout:	feed timeout.
117  * @filter:	pointer to &struct dvb_demux_filter.
118  * @buffer_flags: Buffer flags used to report discontinuity users via DVB
119  *		  memory mapped API, as defined by &enum dmx_buffer_flags.
120  * @ts_type:	type of TS, as defined by &enum ts_filter_type.
121  * @pes_type:	type of PES, as defined by &enum dmx_ts_pes.
122  * @cc:		MPEG-TS packet continuity counter
123  * @pusi_seen:	if true, indicates that a discontinuity was detected.
124  *		it is used to prevent feeding of garbage from previous section.
125  * @peslen:	length of the PES (Packet Elementary Stream).
126  * @list_head:	head for the list of digital TV demux feeds.
127  * @index:	a unique index for each feed. Can be used as hardware
128  *		pid filter index.
129  */
130 struct dvb_demux_feed {
131 	union {
132 		struct dmx_ts_feed ts;
133 		struct dmx_section_feed sec;
134 	} feed;
135 
136 	union {
137 		dmx_ts_cb ts;
138 		dmx_section_cb sec;
139 	} cb;
140 
141 	struct dvb_demux *demux;
142 	void *priv;
143 	enum dvb_dmx_filter_type type;
144 	enum dvb_dmx_state state;
145 	u16 pid;
146 
147 	ktime_t timeout;
148 	struct dvb_demux_filter *filter;
149 
150 	u32 buffer_flags;
151 
152 	enum ts_filter_type ts_type;
153 	enum dmx_ts_pes pes_type;
154 
155 	int cc;
156 	bool pusi_seen;
157 
158 	u16 peslen;
159 
160 	struct list_head list_head;
161 	unsigned int index;
162 };
163 
164 /**
165  * struct dvb_demux - represents a digital TV demux
166  * @dmx:		embedded &struct dmx_demux with demux capabilities
167  *			and callbacks.
168  * @priv:		private data that can optionally be used by
169  *			a DVB driver.
170  * @filternum:		maximum amount of DVB filters.
171  * @feednum:		maximum amount of DVB feeds.
172  * @start_feed:		callback routine to be called in order to start
173  *			a DVB feed.
174  * @stop_feed:		callback routine to be called in order to stop
175  *			a DVB feed.
176  * @write_to_decoder:	callback routine to be called if the feed is TS and
177  *			it is routed to an A/V decoder, when a new TS packet
178  *			is received.
179  *			Used only on av7110-av.c.
180  * @check_crc32:	callback routine to check CRC. If not initialized,
181  *			dvb_demux will use an internal one.
182  * @memcopy:		callback routine to memcopy received data.
183  *			If not initialized, dvb_demux will default to memcpy().
184  * @users:		counter for the number of demux opened file descriptors.
185  *			Currently, it is limited to 10 users.
186  * @filter:		pointer to &struct dvb_demux_filter.
187  * @feed:		pointer to &struct dvb_demux_feed.
188  * @frontend_list:	&struct list_head with frontends used by the demux.
189  * @pesfilter:		array of &struct dvb_demux_feed with the PES types
190  *			that will be filtered.
191  * @pids:		list of filtered program IDs.
192  * @feed_list:		&struct list_head with feeds.
193  * @tsbuf:		temporary buffer used internally to store TS packets.
194  * @tsbufp:		temporary buffer index used internally.
195  * @mutex:		pointer to &struct mutex used to protect feed set
196  *			logic.
197  * @lock:		pointer to &spinlock_t, used to protect buffer handling.
198  * @cnt_storage:	buffer used for TS/TEI continuity check.
199  * @speed_last_time:	&ktime_t used for TS speed check.
200  * @speed_pkts_cnt:	packets count used for TS speed check.
201  */
202 struct dvb_demux {
203 	struct dmx_demux dmx;
204 	void *priv;
205 	int filternum;
206 	int feednum;
207 	int (*start_feed)(struct dvb_demux_feed *feed);
208 	int (*stop_feed)(struct dvb_demux_feed *feed);
209 	int (*write_to_decoder)(struct dvb_demux_feed *feed,
210 				 const u8 *buf, size_t len);
211 	u32 (*check_crc32)(struct dvb_demux_feed *feed,
212 			    const u8 *buf, size_t len);
213 	void (*memcopy)(struct dvb_demux_feed *feed, u8 *dst,
214 			 const u8 *src, size_t len);
215 
216 	int users;
217 #define MAX_DVB_DEMUX_USERS 10
218 	struct dvb_demux_filter *filter;
219 	struct dvb_demux_feed *feed;
220 
221 	struct list_head frontend_list;
222 
223 	struct dvb_demux_feed *pesfilter[DMX_PES_OTHER];
224 	u16 pids[DMX_PES_OTHER];
225 
226 #define DMX_MAX_PID 0x2000
227 	struct list_head feed_list;
228 	u8 tsbuf[204];
229 	int tsbufp;
230 
231 	struct mutex mutex;
232 	spinlock_t lock;
233 
234 	uint8_t *cnt_storage; /* for TS continuity check */
235 
236 	ktime_t speed_last_time; /* for TS speed check */
237 	uint32_t speed_pkts_cnt; /* for TS speed check */
238 
239 	/* private: used only on av7110 */
240 	int playing;
241 	int recording;
242 };
243 
244 /**
245  * dvb_dmx_init - initialize a digital TV demux struct.
246  *
247  * @demux: &struct dvb_demux to be initialized.
248  *
249  * Before being able to register a digital TV demux struct, drivers
250  * should call this routine. On its typical usage, some fields should
251  * be initialized at the driver before calling it.
252  *
253  * A typical usecase is::
254  *
255  *	dvb->demux.dmx.capabilities =
256  *		DMX_TS_FILTERING | DMX_SECTION_FILTERING |
257  *		DMX_MEMORY_BASED_FILTERING;
258  *	dvb->demux.priv       = dvb;
259  *	dvb->demux.filternum  = 256;
260  *	dvb->demux.feednum    = 256;
261  *	dvb->demux.start_feed = driver_start_feed;
262  *	dvb->demux.stop_feed  = driver_stop_feed;
263  *	ret = dvb_dmx_init(&dvb->demux);
264  *	if (ret < 0)
265  *		return ret;
266  */
267 int dvb_dmx_init(struct dvb_demux *demux);
268 
269 /**
270  * dvb_dmx_release - releases a digital TV demux internal buffers.
271  *
272  * @demux: &struct dvb_demux to be released.
273  *
274  * The DVB core internally allocates data at @demux. This routine
275  * releases those data. Please notice that the struct itelf is not
276  * released, as it can be embedded on other structs.
277  */
278 void dvb_dmx_release(struct dvb_demux *demux);
279 
280 /**
281  * dvb_dmx_swfilter_packets - use dvb software filter for a buffer with
282  *	multiple MPEG-TS packets with 188 bytes each.
283  *
284  * @demux: pointer to &struct dvb_demux
285  * @buf: buffer with data to be filtered
286  * @count: number of MPEG-TS packets with size of 188.
287  *
288  * The routine will discard a DVB packet that don't start with 0x47.
289  *
290  * Use this routine if the DVB demux fills MPEG-TS buffers that are
291  * already aligned.
292  *
293  * NOTE: The @buf size should have size equal to ``count * 188``.
294  */
295 void dvb_dmx_swfilter_packets(struct dvb_demux *demux, const u8 *buf,
296 			      size_t count);
297 
298 /**
299  * dvb_dmx_swfilter -  use dvb software filter for a buffer with
300  *	multiple MPEG-TS packets with 188 bytes each.
301  *
302  * @demux: pointer to &struct dvb_demux
303  * @buf: buffer with data to be filtered
304  * @count: number of MPEG-TS packets with size of 188.
305  *
306  * If a DVB packet doesn't start with 0x47, it will seek for the first
307  * byte that starts with 0x47.
308  *
309  * Use this routine if the DVB demux fill buffers that may not start with
310  * a packet start mark (0x47).
311  *
312  * NOTE: The @buf size should have size equal to ``count * 188``.
313  */
314 void dvb_dmx_swfilter(struct dvb_demux *demux, const u8 *buf, size_t count);
315 
316 /**
317  * dvb_dmx_swfilter_204 -  use dvb software filter for a buffer with
318  *	multiple MPEG-TS packets with 204 bytes each.
319  *
320  * @demux: pointer to &struct dvb_demux
321  * @buf: buffer with data to be filtered
322  * @count: number of MPEG-TS packets with size of 204.
323  *
324  * If a DVB packet doesn't start with 0x47, it will seek for the first
325  * byte that starts with 0x47.
326  *
327  * Use this routine if the DVB demux fill buffers that may not start with
328  * a packet start mark (0x47).
329  *
330  * NOTE: The @buf size should have size equal to ``count * 204``.
331  */
332 void dvb_dmx_swfilter_204(struct dvb_demux *demux, const u8 *buf,
333 			  size_t count);
334 
335 /**
336  * dvb_dmx_swfilter_raw -  make the raw data available to userspace without
337  *	filtering
338  *
339  * @demux: pointer to &struct dvb_demux
340  * @buf: buffer with data
341  * @count: number of packets to be passed. The actual size of each packet
342  *	depends on the &dvb_demux->feed->cb.ts logic.
343  *
344  * Use it if the driver needs to deliver the raw payload to userspace without
345  * passing through the kernel demux. That is meant to support some
346  * delivery systems that aren't based on MPEG-TS.
347  *
348  * This function relies on &dvb_demux->feed->cb.ts to actually handle the
349  * buffer.
350  */
351 void dvb_dmx_swfilter_raw(struct dvb_demux *demux, const u8 *buf,
352 			  size_t count);
353 
354 #endif /* _DVB_DEMUX_H_ */
355