summaryrefslogtreecommitdiff
path: root/drivers/media/pci/cx18/cx18-fileops.c
blob: a3f44e30f821921b88acfbffce824c7d42b34744 (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
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
/*
 *  cx18 file operation functions
 *
 *  Derived from ivtv-fileops.c
 *
 *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
 *  Copyright (C) 2008  Andy Walls <awalls@md.metrocast.net>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 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.
 */

#include "cx18-driver.h"
#include "cx18-fileops.h"
#include "cx18-i2c.h"
#include "cx18-queue.h"
#include "cx18-vbi.h"
#include "cx18-audio.h"
#include "cx18-mailbox.h"
#include "cx18-scb.h"
#include "cx18-streams.h"
#include "cx18-controls.h"
#include "cx18-ioctl.h"
#include "cx18-cards.h"
#include <media/v4l2-event.h>

/* This function tries to claim the stream for a specific file descriptor.
   If no one else is using this stream then the stream is claimed and
   associated VBI and IDX streams are also automatically claimed.
   Possible error returns: -EBUSY if someone else has claimed
   the stream or 0 on success. */
int cx18_claim_stream(struct cx18_open_id *id, int type)
{
	struct cx18 *cx = id->cx;
	struct cx18_stream *s = &cx->streams[type];
	struct cx18_stream *s_assoc;

	/* Nothing should ever try to directly claim the IDX stream */
	if (type == CX18_ENC_STREAM_TYPE_IDX) {
		CX18_WARN("MPEG Index stream cannot be claimed directly, but something tried.\n");
		return -EINVAL;
	}

	if (test_and_set_bit(CX18_F_S_CLAIMED, &s->s_flags)) {
		/* someone already claimed this stream */
		if (s->id == id->open_id) {
			/* yes, this file descriptor did. So that's OK. */
			return 0;
		}
		if (s->id == -1 && type == CX18_ENC_STREAM_TYPE_VBI) {
			/* VBI is handled already internally, now also assign
			   the file descriptor to this stream for external
			   reading of the stream. */
			s->id = id->open_id;
			CX18_DEBUG_INFO("Start Read VBI\n");
			return 0;
		}
		/* someone else is using this stream already */
		CX18_DEBUG_INFO("Stream %d is busy\n", type);
		return -EBUSY;
	}
	s->id = id->open_id;

	/*
	 * CX18_ENC_STREAM_TYPE_MPG needs to claim:
	 * CX18_ENC_STREAM_TYPE_VBI, if VBI insertion is on for sliced VBI, or
	 * CX18_ENC_STREAM_TYPE_IDX, if VBI insertion is off for sliced VBI
	 * (We don't yet fix up MPEG Index entries for our inserted packets).
	 *
	 * For all other streams we're done.
	 */
	if (type != CX18_ENC_STREAM_TYPE_MPG)
		return 0;

	s_assoc = &cx->streams[CX18_ENC_STREAM_TYPE_IDX];
	if (cx->vbi.insert_mpeg && !cx18_raw_vbi(cx))
		s_assoc = &cx->streams[CX18_ENC_STREAM_TYPE_VBI];
	else if (!cx18_stream_enabled(s_assoc))
		return 0;

	set_bit(CX18_F_S_CLAIMED, &s_assoc->s_flags);

	/* mark that it is used internally */
	set_bit(CX18_F_S_INTERNAL_USE, &s_assoc->s_flags);
	return 0;
}
EXPORT_SYMBOL(cx18_claim_stream);

/* This function releases a previously claimed stream. It will take into
   account associated VBI streams. */
void cx18_release_stream(struct cx18_stream *s)
{
	struct cx18 *cx = s->cx;
	struct cx18_stream *s_assoc;

	s->id = -1;
	if (s->type == CX18_ENC_STREAM_TYPE_IDX) {
		/*
		 * The IDX stream is only used internally, and can
		 * only be indirectly unclaimed by unclaiming the MPG stream.
		 */
		return;
	}

	if (s->type == CX18_ENC_STREAM_TYPE_VBI &&
		test_bit(CX18_F_S_INTERNAL_USE, &s->s_flags)) {
		/* this stream is still in use internally */
		return;
	}
	if (!test_and_clear_bit(CX18_F_S_CLAIMED, &s->s_flags)) {
		CX18_DEBUG_WARN("Release stream %s not in use!\n", s->name);
		return;
	}

	cx18_flush_queues(s);

	/*
	 * CX18_ENC_STREAM_TYPE_MPG needs to release the
	 * CX18_ENC_STREAM_TYPE_VBI and/or CX18_ENC_STREAM_TYPE_IDX streams.
	 *
	 * For all other streams we're done.
	 */
	if (s->type != CX18_ENC_STREAM_TYPE_MPG)
		return;

	/* Unclaim the associated MPEG Index stream */
	s_assoc = &cx->streams[CX18_ENC_STREAM_TYPE_IDX];
	if (test_and_clear_bit(CX18_F_S_INTERNAL_USE, &s_assoc->s_flags)) {
		clear_bit(CX18_F_S_CLAIMED, &s_assoc->s_flags);
		cx18_flush_queues(s_assoc);
	}

	/* Unclaim the associated VBI stream */
	s_assoc = &cx->streams[CX18_ENC_STREAM_TYPE_VBI];
	if (test_and_clear_bit(CX18_F_S_INTERNAL_USE, &s_assoc->s_flags)) {
		if (s_assoc->id == -1) {
			/*
			 * The VBI stream is not still claimed by a file
			 * descriptor, so completely unclaim it.
			 */
			clear_bit(CX18_F_S_CLAIMED, &s_assoc->s_flags);
			cx18_flush_queues(s_assoc);
		}
	}
}
EXPORT_SYMBOL(cx18_release_stream);

static void cx18_dualwatch(struct cx18 *cx)
{
	struct v4l2_tuner vt;
	u32 new_stereo_mode;
	const u32 dual = 0x0200;

	new_stereo_mode = v4l2_ctrl_g_ctrl(cx->cxhdl.audio_mode);
	memset(&vt, 0, sizeof(vt));
	cx18_call_all(cx, tuner, g_tuner, &vt);
	if (vt.audmode == V4L2_TUNER_MODE_LANG1_LANG2 &&
			(vt.rxsubchans & V4L2_TUNER_SUB_LANG2))
		new_stereo_mode = dual;

	if (new_stereo_mode == cx->dualwatch_stereo_mode)
		return;

	CX18_DEBUG_INFO("dualwatch: change stereo flag from 0x%x to 0x%x.\n",
			   cx->dualwatch_stereo_mode, new_stereo_mode);
	if (v4l2_ctrl_s_ctrl(cx->cxhdl.audio_mode, new_stereo_mode))
		CX18_DEBUG_INFO("dualwatch: changing stereo flag failed\n");
}


static struct cx18_mdl *cx18_get_mdl(struct cx18_stream *s, int non_block,
				     int *err)
{
	struct cx18 *cx = s->cx;
	struct cx18_stream *s_vbi = &cx->streams[CX18_ENC_STREAM_TYPE_VBI];
	struct cx18_mdl *mdl;
	DEFINE_WAIT(wait);

	*err = 0;
	while (1) {
		if (s->type == CX18_ENC_STREAM_TYPE_MPG) {
			/* Process pending program updates and VBI data */
			if (time_after(jiffies, cx->dualwatch_jiffies + msecs_to_jiffies(1000))) {
				cx->dualwatch_jiffies = jiffies;
				cx18_dualwatch(cx);
			}
			if (test_bit(CX18_F_S_INTERNAL_USE, &s_vbi->s_flags) &&
			    !test_bit(CX18_F_S_APPL_IO, &s_vbi->s_flags)) {
				while ((mdl = cx18_dequeue(s_vbi,
							   &s_vbi->q_full))) {
					/* byteswap and process VBI data */
					cx18_process_vbi_data(cx, mdl,
							      s_vbi->type);
					cx18_stream_put_mdl_fw(s_vbi, mdl);
				}
			}
			mdl = &cx->vbi.sliced_mpeg_mdl;
			if (mdl->readpos != mdl->bytesused)
				return mdl;
		}

		/* do we have new data? */
		mdl = cx18_dequeue(s, &s->q_full);
		if (mdl) {
			if (!test_and_clear_bit(CX18_F_M_NEED_SWAP,
						&mdl->m_flags))
				return mdl;
			if (s->type == CX18_ENC_STREAM_TYPE_MPG)
				/* byteswap MPG data */
				cx18_mdl_swap(mdl);
			else {
				/* byteswap and process VBI data */
				cx18_process_vbi_data(cx, mdl, s->type);
			}
			return mdl;
		}

		/* return if end of stream */
		if (!test_bit(CX18_F_S_STREAMING, &s->s_flags)) {
			CX18_DEBUG_INFO("EOS %s\n", s->name);
			return NULL;
		}

		/* return if file was opened with O_NONBLOCK */
		if (non_block) {
			*err = -EAGAIN;
			return NULL;
		}

		/* wait for more data to arrive */
		prepare_to_wait(&s->waitq, &wait, TASK_INTERRUPTIBLE);
		/* New buffers might have become available before we were added
		   to the waitqueue */
		if (!atomic_read(&s->q_full.depth))
			schedule();
		finish_wait(&s->waitq, &wait);
		if (signal_pending(current)) {
			/* return if a signal was received */
			CX18_DEBUG_INFO("User stopped %s\n", s->name);
			*err = -EINTR;
			return NULL;
		}
	}
}

static void cx18_setup_sliced_vbi_mdl(struct cx18 *cx)
{
	struct cx18_mdl *mdl = &cx->vbi.sliced_mpeg_mdl;
	struct cx18_buffer *buf = &cx->vbi.sliced_mpeg_buf;
	int idx = cx->vbi.inserted_frame % CX18_VBI_FRAMES;

	buf->buf = cx->vbi.sliced_mpeg_data[idx];
	buf->bytesused = cx->vbi.sliced_mpeg_size[idx];
	buf->readpos = 0;

	mdl->curr_buf = NULL;
	mdl->bytesused = cx->vbi.sliced_mpeg_size[idx];
	mdl->readpos = 0;
}

static size_t cx18_copy_buf_to_user(struct cx18_stream *s,
	struct cx18_buffer *buf, char __user *ubuf, size_t ucount, bool *stop)
{
	struct cx18 *cx = s->cx;
	size_t len = buf->bytesused - buf->readpos;

	*stop = false;
	if (len > ucount)
		len = ucount;
	if (cx->vbi.insert_mpeg && s->type == CX18_ENC_STREAM_TYPE_MPG &&
	    !cx18_raw_vbi(cx) && buf != &cx->vbi.sliced_mpeg_buf) {
		/*
		 * Try to find a good splice point in the PS, just before
		 * an MPEG-2 Program Pack start code, and provide only
		 * up to that point to the user, so it's easy to insert VBI data
		 * the next time around.
		 *
		 * This will not work for an MPEG-2 TS and has only been
		 * verified by analysis to work for an MPEG-2 PS.  Helen Buus
		 * pointed out this works for the CX23416 MPEG-2 DVD compatible
		 * stream, and research indicates both the MPEG 2 SVCD and DVD
		 * stream types use an MPEG-2 PS container.
		 */
		/*
		 * An MPEG-2 Program Stream (PS) is a series of
		 * MPEG-2 Program Packs terminated by an
		 * MPEG Program End Code after the last Program Pack.
		 * A Program Pack may hold a PS System Header packet and any
		 * number of Program Elementary Stream (PES) Packets
		 */
		const char *start = buf->buf + buf->readpos;
		const char *p = start + 1;
		const u8 *q;
		u8 ch = cx->search_pack_header ? 0xba : 0xe0;
		int stuffing, i;

		while (start + len > p) {
			/* Scan for a 0 to find a potential MPEG-2 start code */
			q = memchr(p, 0, start + len - p);
			if (q == NULL)
				break;
			p = q + 1;
			/*
			 * Keep looking if not a
			 * MPEG-2 Pack header start code:  0x00 0x00 0x01 0xba
			 * or MPEG-2 video PES start code: 0x00 0x00 0x01 0xe0
			 */
			if ((char *)q + 15 >= buf->buf + buf->bytesused ||
			    q[1] != 0 || q[2] != 1 || q[3] != ch)
				continue;

			/* If expecting the primary video PES */
			if (!cx->search_pack_header) {
				/* Continue if it couldn't be a PES packet */
				if ((q[6] & 0xc0) != 0x80)
					continue;
				/* Check if a PTS or PTS & DTS follow */
				if (((q[7] & 0xc0) == 0x80 &&  /* PTS only */
				     (q[9] & 0xf0) == 0x20) || /* PTS only */
				    ((q[7] & 0xc0) == 0xc0 &&  /* PTS & DTS */
				     (q[9] & 0xf0) == 0x30)) { /* DTS follows */
					/* Assume we found the video PES hdr */
					ch = 0xba; /* next want a Program Pack*/
					cx->search_pack_header = 1;
					p = q + 9; /* Skip this video PES hdr */
				}
				continue;
			}

			/* We may have found a Program Pack start code */

			/* Get the count of stuffing bytes & verify them */
			stuffing = q[13] & 7;
			/* all stuffing bytes must be 0xff */
			for (i = 0; i < stuffing; i++)
				if (q[14 + i] != 0xff)
					break;
			if (i == stuffing && /* right number of stuffing bytes*/
			    (q[4] & 0xc4) == 0x44 && /* marker check */
			    (q[12] & 3) == 3 &&  /* marker check */
			    q[14 + stuffing] == 0 && /* PES Pack or Sys Hdr */
			    q[15 + stuffing] == 0 &&
			    q[16 + stuffing] == 1) {
				/* We declare we actually found a Program Pack*/
				cx->search_pack_header = 0; /* expect vid PES */
				len = (char *)q - start;
				cx18_setup_sliced_vbi_mdl(cx);
				*stop = true;
				break;
			}
		}
	}
	if (copy_to_user(ubuf, (u8 *)buf->buf + buf->readpos, len)) {
		CX18_DEBUG_WARN("copy %zd bytes to user failed for %s\n",
				len, s->name);
		return -EFAULT;
	}
	buf->readpos += len;
	if (s->type == CX18_ENC_STREAM_TYPE_MPG &&
	    buf != &cx->vbi.sliced_mpeg_buf)
		cx->mpg_data_received += len;
	return len;
}

static size_t cx18_copy_mdl_to_user(struct cx18_stream *s,
		struct cx18_mdl *mdl, char __user *ubuf, size_t ucount)
{
	size_t tot_written = 0;
	int rc;
	bool stop = false;

	if (mdl->curr_buf == NULL)
		mdl->curr_buf = list_first_entry(&mdl->buf_list,
						 struct cx18_buffer, list);

	if (list_entry_is_past_end(mdl->curr_buf, &mdl->buf_list, list)) {
		/*
		 * For some reason we've exhausted the buffers, but the MDL
		 * object still said some data was unread.
		 * Fix that and bail out.
		 */
		mdl->readpos = mdl->bytesused;
		return 0;
	}

	list_for_each_entry_from(mdl->curr_buf, &mdl->buf_list, list) {

		if (mdl->curr_buf->readpos >= mdl->curr_buf->bytesused)
			continue;

		rc = cx18_copy_buf_to_user(s, mdl->curr_buf, ubuf + tot_written,
					   ucount - tot_written, &stop);
		if (rc < 0)
			return rc;
		mdl->readpos += rc;
		tot_written += rc;

		if (stop ||	/* Forced stopping point for VBI insertion */
		    tot_written >= ucount ||	/* Reader request statisfied */
		    mdl->curr_buf->readpos < mdl->curr_buf->bytesused ||
		    mdl->readpos >= mdl->bytesused) /* MDL buffers drained */
			break;
	}
	return tot_written;
}

static ssize_t cx18_read(struct cx18_stream *s, char __user *ubuf,
		size_t tot_count, int non_block)
{
	struct cx18 *cx = s->cx;
	size_t tot_written = 0;
	int single_frame = 0;

	if (atomic_read(&cx->ana_capturing) == 0 && s->id == -1) {
		/* shouldn't happen */
		CX18_DEBUG_WARN("Stream %s not initialized before read\n",
				s->name);
		return -EIO;
	}

	/* Each VBI buffer is one frame, the v4l2 API says that for VBI the
	   frames should arrive one-by-one, so make sure we never output more
	   than one VBI frame at a time */
	if (s->type == CX18_ENC_STREAM_TYPE_VBI && !cx18_raw_vbi(cx))
		single_frame = 1;

	for (;;) {
		struct cx18_mdl *mdl;
		int rc;

		mdl = cx18_get_mdl(s, non_block, &rc);
		/* if there is no data available... */
		if (mdl == NULL) {
			/* if we got data, then return that regardless */
			if (tot_written)
				break;
			/* EOS condition */
			if (rc == 0) {
				clear_bit(CX18_F_S_STREAMOFF, &s->s_flags);
				clear_bit(CX18_F_S_APPL_IO, &s->s_flags);
				cx18_release_stream(s);
			}
			/* set errno */
			return rc;
		}

		rc = cx18_copy_mdl_to_user(s, mdl, ubuf + tot_written,
				tot_count - tot_written);

		if (mdl != &cx->vbi.sliced_mpeg_mdl) {
			if (mdl->readpos == mdl->bytesused)
				cx18_stream_put_mdl_fw(s, mdl);
			else
				cx18_push(s, mdl, &s->q_full);
		} else if (mdl->readpos == mdl->bytesused) {
			int idx = cx->vbi.inserted_frame % CX18_VBI_FRAMES;

			cx->vbi.sliced_mpeg_size[idx] = 0;
			cx->vbi.inserted_frame++;
			cx->vbi_data_inserted += mdl->bytesused;
		}
		if (rc < 0)
			return rc;
		tot_written += rc;

		if (tot_written == tot_count || single_frame)
			break;
	}
	return tot_written;
}

static ssize_t cx18_read_pos(struct cx18_stream *s, char __user *ubuf,
		size_t count, loff_t *pos, int non_block)
{
	ssize_t rc = count ? cx18_read(s, ubuf, count, non_block) : 0;
	struct cx18 *cx = s->cx;

	CX18_DEBUG_HI_FILE("read %zd from %s, got %zd\n", count, s->name, rc);
	if (rc > 0)
		pos += rc;
	return rc;
}

int cx18_start_capture(struct cx18_open_id *id)
{
	struct cx18 *cx = id->cx;
	struct cx18_stream *s = &cx->streams[id->type];
	struct cx18_stream *s_vbi;
	struct cx18_stream *s_idx;

	if (s->type == CX18_ENC_STREAM_TYPE_RAD) {
		/* you cannot read from these stream types. */
		return -EPERM;
	}

	/* Try to claim this stream. */
	if (cx18_claim_stream(id, s->type))
		return -EBUSY;

	/* If capture is already in progress, then we also have to
	   do nothing extra. */
	if (test_bit(CX18_F_S_STREAMOFF, &s->s_flags) ||
	    test_and_set_bit(CX18_F_S_STREAMING, &s->s_flags)) {
		set_bit(CX18_F_S_APPL_IO, &s->s_flags);
		return 0;
	}

	/* Start associated VBI or IDX stream capture if required */
	s_vbi = &cx->streams[CX18_ENC_STREAM_TYPE_VBI];
	s_idx = &cx->streams[CX18_ENC_STREAM_TYPE_IDX];
	if (s->type == CX18_ENC_STREAM_TYPE_MPG) {
		/*
		 * The VBI and IDX streams should have been claimed
		 * automatically, if for internal use, when the MPG stream was
		 * claimed.  We only need to start these streams capturing.
		 */
		if (test_bit(CX18_F_S_INTERNAL_USE, &s_idx->s_flags) &&
		    !test_and_set_bit(CX18_F_S_STREAMING, &s_idx->s_flags)) {
			if (cx18_start_v4l2_encode_stream(s_idx)) {
				CX18_DEBUG_WARN("IDX capture start failed\n");
				clear_bit(CX18_F_S_STREAMING, &s_idx->s_flags);
				goto start_failed;
			}
			CX18_DEBUG_INFO("IDX capture started\n");
		}
		if (test_bit(CX18_F_S_INTERNAL_USE, &s_vbi->s_flags) &&
		    !test_and_set_bit(CX18_F_S_STREAMING, &s_vbi->s_flags)) {
			if (cx18_start_v4l2_encode_stream(s_vbi)) {
				CX18_DEBUG_WARN("VBI capture start failed\n");
				clear_bit(CX18_F_S_STREAMING, &s_vbi->s_flags);
				goto start_failed;
			}
			CX18_DEBUG_INFO("VBI insertion started\n");
		}
	}

	/* Tell the card to start capturing */
	if (!cx18_start_v4l2_encode_stream(s)) {
		/* We're done */
		set_bit(CX18_F_S_APPL_IO, &s->s_flags);
		/* Resume a possibly paused encoder */
		if (test_and_clear_bit(CX18_F_I_ENC_PAUSED, &cx->i_flags))
			cx18_vapi(cx, CX18_CPU_CAPTURE_PAUSE, 1, s->handle);
		return 0;
	}

start_failed:
	CX18_DEBUG_WARN("Failed to start capturing for stream %s\n", s->name);

	/*
	 * The associated VBI and IDX streams for internal use are released
	 * automatically when the MPG stream is released.  We only need to stop
	 * the associated stream.
	 */
	if (s->type == CX18_ENC_STREAM_TYPE_MPG) {
		/* Stop the IDX stream which is always for internal use */
		if (test_bit(CX18_F_S_STREAMING, &s_idx->s_flags)) {
			cx18_stop_v4l2_encode_stream(s_idx, 0);
			clear_bit(CX18_F_S_STREAMING, &s_idx->s_flags);
		}
		/* Stop the VBI stream, if only running for internal use */
		if (test_bit(CX18_F_S_STREAMING, &s_vbi->s_flags) &&
		    !test_bit(CX18_F_S_APPL_IO, &s_vbi->s_flags)) {
			cx18_stop_v4l2_encode_stream(s_vbi, 0);
			clear_bit(CX18_F_S_STREAMING, &s_vbi->s_flags);
		}
	}
	clear_bit(CX18_F_S_STREAMING, &s->s_flags);
	cx18_release_stream(s); /* Also releases associated streams */
	return -EIO;
}

ssize_t cx18_v4l2_read(struct file *filp, char __user *buf, size_t count,
		loff_t *pos)
{
	struct cx18_open_id *id = file2id(filp);
	struct cx18 *cx = id->cx;
	struct cx18_stream *s = &cx->streams[id->type];
	int rc;

	CX18_DEBUG_HI_FILE("read %zd bytes from %s\n", count, s->name);

	mutex_lock(&cx->serialize_lock);
	rc = cx18_start_capture(id);
	mutex_unlock(&cx->serialize_lock);
	if (rc)
		return rc;

	if ((s->vb_type == V4L2_BUF_TYPE_VIDEO_CAPTURE) &&
		(id->type == CX18_ENC_STREAM_TYPE_YUV)) {
		return videobuf_read_stream(&s->vbuf_q, buf, count, pos, 0,
			filp->f_flags & O_NONBLOCK);
	}

	return cx18_read_pos(s, buf, count, pos, filp->f_flags & O_NONBLOCK);
}

__poll_t cx18_v4l2_enc_poll(struct file *filp, poll_table *wait)
{
	__poll_t req_events = poll_requested_events(wait);
	struct cx18_open_id *id = file2id(filp);
	struct cx18 *cx = id->cx;
	struct cx18_stream *s = &cx->streams[id->type];
	int eof = test_bit(CX18_F_S_STREAMOFF, &s->s_flags);
	__poll_t res = 0;

	/* Start a capture if there is none */
	if (!eof && !test_bit(CX18_F_S_STREAMING, &s->s_flags) &&
			(req_events & (EPOLLIN | EPOLLRDNORM))) {
		int rc;

		mutex_lock(&cx->serialize_lock);
		rc = cx18_start_capture(id);
		mutex_unlock(&cx->serialize_lock);
		if (rc) {
			CX18_DEBUG_INFO("Could not start capture for %s (%d)\n",
					s->name, rc);
			return EPOLLERR;
		}
		CX18_DEBUG_FILE("Encoder poll started capture\n");
	}

	if ((s->vb_type == V4L2_BUF_TYPE_VIDEO_CAPTURE) &&
		(id->type == CX18_ENC_STREAM_TYPE_YUV)) {
		__poll_t videobuf_poll = videobuf_poll_stream(filp, &s->vbuf_q, wait);

		if (v4l2_event_pending(&id->fh))
			res |= EPOLLPRI;
		if (eof && videobuf_poll == EPOLLERR)
			return res | EPOLLHUP;
		return res | videobuf_poll;
	}

	/* add stream's waitq to the poll list */
	CX18_DEBUG_HI_FILE("Encoder poll\n");
	if (v4l2_event_pending(&id->fh))
		res |= EPOLLPRI;
	else
		poll_wait(filp, &s->waitq, wait);

	if (atomic_read(&s->q_full.depth))
		return res | EPOLLIN | EPOLLRDNORM;
	if (eof)
		return res | EPOLLHUP;
	return res;
}

int cx18_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct cx18_open_id *id = file->private_data;
	struct cx18 *cx = id->cx;
	struct cx18_stream *s = &cx->streams[id->type];
	int eof = test_bit(CX18_F_S_STREAMOFF, &s->s_flags);

	if ((s->vb_type == V4L2_BUF_TYPE_VIDEO_CAPTURE) &&
		(id->type == CX18_ENC_STREAM_TYPE_YUV)) {

		/* Start a capture if there is none */
		if (!eof && !test_bit(CX18_F_S_STREAMING, &s->s_flags)) {
			int rc;

			mutex_lock(&cx->serialize_lock);
			rc = cx18_start_capture(id);
			mutex_unlock(&cx->serialize_lock);
			if (rc) {
				CX18_DEBUG_INFO(
					"Could not start capture for %s (%d)\n",
					s->name, rc);
				return -EINVAL;
			}
			CX18_DEBUG_FILE("Encoder mmap started capture\n");
		}

		return videobuf_mmap_mapper(&s->vbuf_q, vma);
	}

	return -EINVAL;
}

void cx18_vb_timeout(struct timer_list *t)
{
	struct cx18_stream *s = from_timer(s, t, vb_timeout);
	struct cx18_videobuf_buffer *buf;
	unsigned long flags;

	/* Return all of the buffers in error state, so the vbi/vid inode
	 * can return from blocking.
	 */
	spin_lock_irqsave(&s->vb_lock, flags);
	while (!list_empty(&s->vb_capture)) {
		buf = list_entry(s->vb_capture.next,
			struct cx18_videobuf_buffer, vb.queue);
		list_del(&buf->vb.queue);
		buf->vb.state = VIDEOBUF_ERROR;
		wake_up(&buf->vb.done);
	}
	spin_unlock_irqrestore(&s->vb_lock, flags);
}

void cx18_stop_capture(struct cx18_open_id *id, int gop_end)
{
	struct cx18 *cx = id->cx;
	struct cx18_stream *s = &cx->streams[id->type];
	struct cx18_stream *s_vbi = &cx->streams[CX18_ENC_STREAM_TYPE_VBI];
	struct cx18_stream *s_idx = &cx->streams[CX18_ENC_STREAM_TYPE_IDX];

	CX18_DEBUG_IOCTL("close() of %s\n", s->name);

	/* 'Unclaim' this stream */

	/* Stop capturing */
	if (test_bit(CX18_F_S_STREAMING, &s->s_flags)) {
		CX18_DEBUG_INFO("close stopping capture\n");
		if (id->type == CX18_ENC_STREAM_TYPE_MPG) {
			/* Stop internal use associated VBI and IDX streams */
			if (test_bit(CX18_F_S_STREAMING, &s_vbi->s_flags) &&
			    !test_bit(CX18_F_S_APPL_IO, &s_vbi->s_flags)) {
				CX18_DEBUG_INFO("close stopping embedded VBI capture\n");
				cx18_stop_v4l2_encode_stream(s_vbi, 0);
			}
			if (test_bit(CX18_F_S_STREAMING, &s_idx->s_flags)) {
				CX18_DEBUG_INFO("close stopping IDX capture\n");
				cx18_stop_v4l2_encode_stream(s_idx, 0);
			}
		}
		if (id->type == CX18_ENC_STREAM_TYPE_VBI &&
		    test_bit(CX18_F_S_INTERNAL_USE, &s->s_flags))
			/* Also used internally, don't stop capturing */
			s->id = -1;
		else
			cx18_stop_v4l2_encode_stream(s, gop_end);
	}
	if (!gop_end) {
		clear_bit(CX18_F_S_APPL_IO, &s->s_flags);
		clear_bit(CX18_F_S_STREAMOFF, &s->s_flags);
		cx18_release_stream(s);
	}
}

int cx18_v4l2_close(struct file *filp)
{
	struct v4l2_fh *fh = filp->private_data;
	struct cx18_open_id *id = fh2id(fh);
	struct cx18 *cx = id->cx;
	struct cx18_stream *s = &cx->streams[id->type];

	CX18_DEBUG_IOCTL("close() of %s\n", s->name);

	mutex_lock(&cx->serialize_lock);
	/* Stop radio */
	if (id->type == CX18_ENC_STREAM_TYPE_RAD &&
			v4l2_fh_is_singular_file(filp)) {
		/* Closing radio device, return to TV mode */
		cx18_mute(cx);
		/* Mark that the radio is no longer in use */
		clear_bit(CX18_F_I_RADIO_USER, &cx->i_flags);
		/* Switch tuner to TV */
		cx18_call_all(cx, video, s_std, cx->std);
		/* Select correct audio input (i.e. TV tuner or Line in) */
		cx18_audio_set_io(cx);
		if (atomic_read(&cx->ana_capturing) > 0) {
			/* Undo video mute */
			cx18_vapi(cx, CX18_CPU_SET_VIDEO_MUTE, 2, s->handle,
			    (v4l2_ctrl_g_ctrl(cx->cxhdl.video_mute) |
			    (v4l2_ctrl_g_ctrl(cx->cxhdl.video_mute_yuv) << 8)));
		}
		/* Done! Unmute and continue. */
		cx18_unmute(cx);
	}

	v4l2_fh_del(fh);
	v4l2_fh_exit(fh);

	/* 'Unclaim' this stream */
	if (s->id == id->open_id)
		cx18_stop_capture(id, 0);
	kfree(id);
	mutex_unlock(&cx->serialize_lock);
	return 0;
}

static int cx18_serialized_open(struct cx18_stream *s, struct file *filp)
{
	struct cx18 *cx = s->cx;
	struct cx18_open_id *item;

	CX18_DEBUG_FILE("open %s\n", s->name);

	/* Allocate memory */
	item = kzalloc(sizeof(struct cx18_open_id), GFP_KERNEL);
	if (NULL == item) {
		CX18_DEBUG_WARN("nomem on v4l2 open\n");
		return -ENOMEM;
	}
	v4l2_fh_init(&item->fh, &s->video_dev);

	item->cx = cx;
	item->type = s->type;

	item->open_id = cx->open_id++;
	filp->private_data = &item->fh;
	v4l2_fh_add(&item->fh);

	if (item->type == CX18_ENC_STREAM_TYPE_RAD &&
			v4l2_fh_is_singular_file(filp)) {
		if (!test_bit(CX18_F_I_RADIO_USER, &cx->i_flags)) {
			if (atomic_read(&cx->ana_capturing) > 0) {
				/* switching to radio while capture is
				   in progress is not polite */
				v4l2_fh_del(&item->fh);
				v4l2_fh_exit(&item->fh);
				kfree(item);
				return -EBUSY;
			}
		}

		/* Mark that the radio is being used. */
		set_bit(CX18_F_I_RADIO_USER, &cx->i_flags);
		/* We have the radio */
		cx18_mute(cx);
		/* Switch tuner to radio */
		cx18_call_all(cx, tuner, s_radio);
		/* Select the correct audio input (i.e. radio tuner) */
		cx18_audio_set_io(cx);
		/* Done! Unmute and continue. */
		cx18_unmute(cx);
	}
	return 0;
}

int cx18_v4l2_open(struct file *filp)
{
	int res;
	struct video_device *video_dev = video_devdata(filp);
	struct cx18_stream *s = video_get_drvdata(video_dev);
	struct cx18 *cx = s->cx;

	mutex_lock(&cx->serialize_lock);
	if (cx18_init_on_first_open(cx)) {
		CX18_ERR("Failed to initialize on %s\n",
			 video_device_node_name(video_dev));
		mutex_unlock(&cx->serialize_lock);
		return -ENXIO;
	}
	res = cx18_serialized_open(s, filp);
	mutex_unlock(&cx->serialize_lock);
	return res;
}

void cx18_mute(struct cx18 *cx)
{
	u32 h;
	if (atomic_read(&cx->ana_capturing)) {
		h = cx18_find_handle(cx);
		if (h != CX18_INVALID_TASK_HANDLE)
			cx18_vapi(cx, CX18_CPU_SET_AUDIO_MUTE, 2, h, 1);
		else
			CX18_ERR("Can't find valid task handle for mute\n");
	}
	CX18_DEBUG_INFO("Mute\n");
}

void cx18_unmute(struct cx18 *cx)
{
	u32 h;
	if (atomic_read(&cx->ana_capturing)) {
		h = cx18_find_handle(cx);
		if (h != CX18_INVALID_TASK_HANDLE) {
			cx18_msleep_timeout(100, 0);
			cx18_vapi(cx, CX18_CPU_SET_MISC_PARAMETERS, 2, h, 12);
			cx18_vapi(cx, CX18_CPU_SET_AUDIO_MUTE, 2, h, 0);
		} else
			CX18_ERR("Can't find valid task handle for unmute\n");
	}
	CX18_DEBUG_INFO("Unmute\n");
}