1 /*
2 * oxfw_stream.c - a part of driver for OXFW970/971 based devices
3 *
4 * Copyright (c) 2014 Takashi Sakamoto
5 *
6 * Licensed under the terms of the GNU General Public License, version 2.
7 */
8
9 #include "oxfw.h"
10 #include <linux/delay.h>
11
12 #define AVC_GENERIC_FRAME_MAXIMUM_BYTES 512
13 #define CALLBACK_TIMEOUT 200
14
15 /*
16 * According to datasheet of Oxford Semiconductor:
17 * OXFW970: 32.0/44.1/48.0/96.0 Khz, 8 audio channels I/O
18 * OXFW971: 32.0/44.1/48.0/88.2/96.0/192.0 kHz, 16 audio channels I/O, MIDI I/O
19 */
20 static const unsigned int oxfw_rate_table[] = {
21 [0] = 32000,
22 [1] = 44100,
23 [2] = 48000,
24 [3] = 88200,
25 [4] = 96000,
26 [5] = 192000,
27 };
28
29 /*
30 * See Table 5.7 – Sampling frequency for Multi-bit Audio
31 * in AV/C Stream Format Information Specification 1.1 (Apr 2005, 1394TA)
32 */
33 static const unsigned int avc_stream_rate_table[] = {
34 [0] = 0x02,
35 [1] = 0x03,
36 [2] = 0x04,
37 [3] = 0x0a,
38 [4] = 0x05,
39 [5] = 0x07,
40 };
41
set_rate(struct snd_oxfw * oxfw,unsigned int rate)42 static int set_rate(struct snd_oxfw *oxfw, unsigned int rate)
43 {
44 int err;
45
46 err = avc_general_set_sig_fmt(oxfw->unit, rate,
47 AVC_GENERAL_PLUG_DIR_IN, 0);
48 if (err < 0)
49 goto end;
50
51 if (oxfw->has_output)
52 err = avc_general_set_sig_fmt(oxfw->unit, rate,
53 AVC_GENERAL_PLUG_DIR_OUT, 0);
54 end:
55 return err;
56 }
57
set_stream_format(struct snd_oxfw * oxfw,struct amdtp_stream * s,unsigned int rate,unsigned int pcm_channels)58 static int set_stream_format(struct snd_oxfw *oxfw, struct amdtp_stream *s,
59 unsigned int rate, unsigned int pcm_channels)
60 {
61 u8 **formats;
62 struct snd_oxfw_stream_formation formation;
63 enum avc_general_plug_dir dir;
64 unsigned int len;
65 int i, err;
66
67 if (s == &oxfw->tx_stream) {
68 formats = oxfw->tx_stream_formats;
69 dir = AVC_GENERAL_PLUG_DIR_OUT;
70 } else {
71 formats = oxfw->rx_stream_formats;
72 dir = AVC_GENERAL_PLUG_DIR_IN;
73 }
74
75 /* Seek stream format for requirements. */
76 for (i = 0; i < SND_OXFW_STREAM_FORMAT_ENTRIES; i++) {
77 err = snd_oxfw_stream_parse_format(formats[i], &formation);
78 if (err < 0)
79 return err;
80
81 if ((formation.rate == rate) && (formation.pcm == pcm_channels))
82 break;
83 }
84 if (i == SND_OXFW_STREAM_FORMAT_ENTRIES)
85 return -EINVAL;
86
87 /* If assumed, just change rate. */
88 if (oxfw->assumed)
89 return set_rate(oxfw, rate);
90
91 /* Calculate format length. */
92 len = 5 + formats[i][4] * 2;
93
94 err = avc_stream_set_format(oxfw->unit, dir, 0, formats[i], len);
95 if (err < 0)
96 return err;
97
98 /* Some requests just after changing format causes freezing. */
99 msleep(100);
100
101 return 0;
102 }
103
stop_stream(struct snd_oxfw * oxfw,struct amdtp_stream * stream)104 static void stop_stream(struct snd_oxfw *oxfw, struct amdtp_stream *stream)
105 {
106 amdtp_stream_pcm_abort(stream);
107 amdtp_stream_stop(stream);
108
109 if (stream == &oxfw->tx_stream)
110 cmp_connection_break(&oxfw->out_conn);
111 else
112 cmp_connection_break(&oxfw->in_conn);
113 }
114
start_stream(struct snd_oxfw * oxfw,struct amdtp_stream * stream,unsigned int rate,unsigned int pcm_channels)115 static int start_stream(struct snd_oxfw *oxfw, struct amdtp_stream *stream,
116 unsigned int rate, unsigned int pcm_channels)
117 {
118 u8 **formats;
119 struct cmp_connection *conn;
120 struct snd_oxfw_stream_formation formation;
121 unsigned int i, midi_ports;
122 int err;
123
124 if (stream == &oxfw->rx_stream) {
125 formats = oxfw->rx_stream_formats;
126 conn = &oxfw->in_conn;
127 } else {
128 formats = oxfw->tx_stream_formats;
129 conn = &oxfw->out_conn;
130 }
131
132 /* Get stream format */
133 for (i = 0; i < SND_OXFW_STREAM_FORMAT_ENTRIES; i++) {
134 if (formats[i] == NULL)
135 break;
136
137 err = snd_oxfw_stream_parse_format(formats[i], &formation);
138 if (err < 0)
139 goto end;
140 if (rate != formation.rate)
141 continue;
142 if (pcm_channels == 0 || pcm_channels == formation.pcm)
143 break;
144 }
145 if (i == SND_OXFW_STREAM_FORMAT_ENTRIES) {
146 err = -EINVAL;
147 goto end;
148 }
149
150 pcm_channels = formation.pcm;
151 midi_ports = formation.midi * 8;
152
153 /* The stream should have one pcm channels at least */
154 if (pcm_channels == 0) {
155 err = -EINVAL;
156 goto end;
157 }
158 err = amdtp_am824_set_parameters(stream, rate, pcm_channels, midi_ports,
159 false);
160 if (err < 0)
161 goto end;
162
163 err = cmp_connection_establish(conn,
164 amdtp_stream_get_max_payload(stream));
165 if (err < 0)
166 goto end;
167
168 err = amdtp_stream_start(stream,
169 conn->resources.channel,
170 conn->speed);
171 if (err < 0) {
172 cmp_connection_break(conn);
173 goto end;
174 }
175
176 /* Wait first packet */
177 if (!amdtp_stream_wait_callback(stream, CALLBACK_TIMEOUT)) {
178 stop_stream(oxfw, stream);
179 err = -ETIMEDOUT;
180 }
181 end:
182 return err;
183 }
184
check_connection_used_by_others(struct snd_oxfw * oxfw,struct amdtp_stream * stream)185 static int check_connection_used_by_others(struct snd_oxfw *oxfw,
186 struct amdtp_stream *stream)
187 {
188 struct cmp_connection *conn;
189 bool used;
190 int err;
191
192 if (stream == &oxfw->tx_stream)
193 conn = &oxfw->out_conn;
194 else
195 conn = &oxfw->in_conn;
196
197 err = cmp_connection_check_used(conn, &used);
198 if ((err >= 0) && used && !amdtp_stream_running(stream)) {
199 dev_err(&oxfw->unit->device,
200 "Connection established by others: %cPCR[%d]\n",
201 (conn->direction == CMP_OUTPUT) ? 'o' : 'i',
202 conn->pcr_index);
203 err = -EBUSY;
204 }
205
206 return err;
207 }
208
snd_oxfw_stream_init_simplex(struct snd_oxfw * oxfw,struct amdtp_stream * stream)209 int snd_oxfw_stream_init_simplex(struct snd_oxfw *oxfw,
210 struct amdtp_stream *stream)
211 {
212 struct cmp_connection *conn;
213 enum cmp_direction c_dir;
214 enum amdtp_stream_direction s_dir;
215 int err;
216
217 if (stream == &oxfw->tx_stream) {
218 conn = &oxfw->out_conn;
219 c_dir = CMP_OUTPUT;
220 s_dir = AMDTP_IN_STREAM;
221 } else {
222 conn = &oxfw->in_conn;
223 c_dir = CMP_INPUT;
224 s_dir = AMDTP_OUT_STREAM;
225 }
226
227 err = cmp_connection_init(conn, oxfw->unit, c_dir, 0);
228 if (err < 0)
229 goto end;
230
231 err = amdtp_am824_init(stream, oxfw->unit, s_dir, CIP_NONBLOCKING);
232 if (err < 0) {
233 amdtp_stream_destroy(stream);
234 cmp_connection_destroy(conn);
235 goto end;
236 }
237
238 /*
239 * OXFW starts to transmit packets with non-zero dbc.
240 * OXFW postpone transferring packets till handling any asynchronous
241 * packets. As a result, next isochronous packet includes more data
242 * blocks than IEC 61883-6 defines.
243 */
244 if (stream == &oxfw->tx_stream) {
245 oxfw->tx_stream.flags |= CIP_JUMBO_PAYLOAD;
246 if (oxfw->wrong_dbs)
247 oxfw->tx_stream.flags |= CIP_WRONG_DBS;
248 }
249 end:
250 return err;
251 }
252
snd_oxfw_stream_start_simplex(struct snd_oxfw * oxfw,struct amdtp_stream * stream,unsigned int rate,unsigned int pcm_channels)253 int snd_oxfw_stream_start_simplex(struct snd_oxfw *oxfw,
254 struct amdtp_stream *stream,
255 unsigned int rate, unsigned int pcm_channels)
256 {
257 struct amdtp_stream *opposite;
258 struct snd_oxfw_stream_formation formation;
259 enum avc_general_plug_dir dir;
260 unsigned int substreams, opposite_substreams;
261 int err = 0;
262
263 if (stream == &oxfw->tx_stream) {
264 substreams = oxfw->capture_substreams;
265 opposite = &oxfw->rx_stream;
266 opposite_substreams = oxfw->playback_substreams;
267 dir = AVC_GENERAL_PLUG_DIR_OUT;
268 } else {
269 substreams = oxfw->playback_substreams;
270 opposite_substreams = oxfw->capture_substreams;
271
272 if (oxfw->has_output)
273 opposite = &oxfw->rx_stream;
274 else
275 opposite = NULL;
276
277 dir = AVC_GENERAL_PLUG_DIR_IN;
278 }
279
280 if (substreams == 0)
281 goto end;
282
283 /*
284 * Considering JACK/FFADO streaming:
285 * TODO: This can be removed hwdep functionality becomes popular.
286 */
287 err = check_connection_used_by_others(oxfw, stream);
288 if (err < 0)
289 goto end;
290
291 /* packet queueing error */
292 if (amdtp_streaming_error(stream))
293 stop_stream(oxfw, stream);
294
295 err = snd_oxfw_stream_get_current_formation(oxfw, dir, &formation);
296 if (err < 0)
297 goto end;
298 if (rate == 0)
299 rate = formation.rate;
300 if (pcm_channels == 0)
301 pcm_channels = formation.pcm;
302
303 if ((formation.rate != rate) || (formation.pcm != pcm_channels)) {
304 if (opposite != NULL) {
305 err = check_connection_used_by_others(oxfw, opposite);
306 if (err < 0)
307 goto end;
308 stop_stream(oxfw, opposite);
309 }
310 stop_stream(oxfw, stream);
311
312 err = set_stream_format(oxfw, stream, rate, pcm_channels);
313 if (err < 0) {
314 dev_err(&oxfw->unit->device,
315 "fail to set stream format: %d\n", err);
316 goto end;
317 }
318
319 /* Start opposite stream if needed. */
320 if (opposite && !amdtp_stream_running(opposite) &&
321 (opposite_substreams > 0)) {
322 err = start_stream(oxfw, opposite, rate, 0);
323 if (err < 0) {
324 dev_err(&oxfw->unit->device,
325 "fail to restart stream: %d\n", err);
326 goto end;
327 }
328 }
329 }
330
331 /* Start requested stream. */
332 if (!amdtp_stream_running(stream)) {
333 err = start_stream(oxfw, stream, rate, pcm_channels);
334 if (err < 0)
335 dev_err(&oxfw->unit->device,
336 "fail to start stream: %d\n", err);
337 }
338 end:
339 return err;
340 }
341
snd_oxfw_stream_stop_simplex(struct snd_oxfw * oxfw,struct amdtp_stream * stream)342 void snd_oxfw_stream_stop_simplex(struct snd_oxfw *oxfw,
343 struct amdtp_stream *stream)
344 {
345 if (((stream == &oxfw->tx_stream) && (oxfw->capture_substreams > 0)) ||
346 ((stream == &oxfw->rx_stream) && (oxfw->playback_substreams > 0)))
347 return;
348
349 stop_stream(oxfw, stream);
350 }
351
352 /*
353 * This function should be called before starting the stream or after stopping
354 * the streams.
355 */
snd_oxfw_stream_destroy_simplex(struct snd_oxfw * oxfw,struct amdtp_stream * stream)356 void snd_oxfw_stream_destroy_simplex(struct snd_oxfw *oxfw,
357 struct amdtp_stream *stream)
358 {
359 struct cmp_connection *conn;
360
361 if (stream == &oxfw->tx_stream)
362 conn = &oxfw->out_conn;
363 else
364 conn = &oxfw->in_conn;
365
366 amdtp_stream_destroy(stream);
367 cmp_connection_destroy(conn);
368 }
369
snd_oxfw_stream_update_simplex(struct snd_oxfw * oxfw,struct amdtp_stream * stream)370 void snd_oxfw_stream_update_simplex(struct snd_oxfw *oxfw,
371 struct amdtp_stream *stream)
372 {
373 struct cmp_connection *conn;
374
375 if (stream == &oxfw->tx_stream)
376 conn = &oxfw->out_conn;
377 else
378 conn = &oxfw->in_conn;
379
380 if (cmp_connection_update(conn) < 0)
381 stop_stream(oxfw, stream);
382 else
383 amdtp_stream_update(stream);
384 }
385
snd_oxfw_stream_get_current_formation(struct snd_oxfw * oxfw,enum avc_general_plug_dir dir,struct snd_oxfw_stream_formation * formation)386 int snd_oxfw_stream_get_current_formation(struct snd_oxfw *oxfw,
387 enum avc_general_plug_dir dir,
388 struct snd_oxfw_stream_formation *formation)
389 {
390 u8 *format;
391 unsigned int len;
392 int err;
393
394 len = AVC_GENERIC_FRAME_MAXIMUM_BYTES;
395 format = kmalloc(len, GFP_KERNEL);
396 if (format == NULL)
397 return -ENOMEM;
398
399 err = avc_stream_get_format_single(oxfw->unit, dir, 0, format, &len);
400 if (err < 0)
401 goto end;
402 if (len < 3) {
403 err = -EIO;
404 goto end;
405 }
406
407 err = snd_oxfw_stream_parse_format(format, formation);
408 end:
409 kfree(format);
410 return err;
411 }
412
413 /*
414 * See Table 6.16 - AM824 Stream Format
415 * Figure 6.19 - format_information field for AM824 Compound
416 * in AV/C Stream Format Information Specification 1.1 (Apr 2005, 1394TA)
417 * Also 'Clause 12 AM824 sequence adaption layers' in IEC 61883-6:2005
418 */
snd_oxfw_stream_parse_format(u8 * format,struct snd_oxfw_stream_formation * formation)419 int snd_oxfw_stream_parse_format(u8 *format,
420 struct snd_oxfw_stream_formation *formation)
421 {
422 unsigned int i, e, channels, type;
423
424 memset(formation, 0, sizeof(struct snd_oxfw_stream_formation));
425
426 /*
427 * this module can support a hierarchy combination that:
428 * Root: Audio and Music (0x90)
429 * Level 1: AM824 Compound (0x40)
430 */
431 if ((format[0] != 0x90) || (format[1] != 0x40))
432 return -ENOSYS;
433
434 /* check the sampling rate */
435 for (i = 0; i < ARRAY_SIZE(avc_stream_rate_table); i++) {
436 if (format[2] == avc_stream_rate_table[i])
437 break;
438 }
439 if (i == ARRAY_SIZE(avc_stream_rate_table))
440 return -ENOSYS;
441
442 formation->rate = oxfw_rate_table[i];
443
444 for (e = 0; e < format[4]; e++) {
445 channels = format[5 + e * 2];
446 type = format[6 + e * 2];
447
448 switch (type) {
449 /* IEC 60958 Conformant, currently handled as MBLA */
450 case 0x00:
451 /* Multi Bit Linear Audio (Raw) */
452 case 0x06:
453 formation->pcm += channels;
454 break;
455 /* MIDI Conformant */
456 case 0x0d:
457 formation->midi = channels;
458 break;
459 /* IEC 61937-3 to 7 */
460 case 0x01:
461 case 0x02:
462 case 0x03:
463 case 0x04:
464 case 0x05:
465 /* Multi Bit Linear Audio */
466 case 0x07: /* DVD-Audio */
467 case 0x0c: /* High Precision */
468 /* One Bit Audio */
469 case 0x08: /* (Plain) Raw */
470 case 0x09: /* (Plain) SACD */
471 case 0x0a: /* (Encoded) Raw */
472 case 0x0b: /* (Encoded) SACD */
473 /* SMPTE Time-Code conformant */
474 case 0x0e:
475 /* Sample Count */
476 case 0x0f:
477 /* Anciliary Data */
478 case 0x10:
479 /* Synchronization Stream (Stereo Raw audio) */
480 case 0x40:
481 /* Don't care */
482 case 0xff:
483 default:
484 return -ENOSYS; /* not supported */
485 }
486 }
487
488 if (formation->pcm > AM824_MAX_CHANNELS_FOR_PCM ||
489 formation->midi > AM824_MAX_CHANNELS_FOR_MIDI)
490 return -ENOSYS;
491
492 return 0;
493 }
494
495 static int
assume_stream_formats(struct snd_oxfw * oxfw,enum avc_general_plug_dir dir,unsigned int pid,u8 * buf,unsigned int * len,u8 ** formats)496 assume_stream_formats(struct snd_oxfw *oxfw, enum avc_general_plug_dir dir,
497 unsigned int pid, u8 *buf, unsigned int *len,
498 u8 **formats)
499 {
500 struct snd_oxfw_stream_formation formation;
501 unsigned int i, eid;
502 int err;
503
504 /* get format at current sampling rate */
505 err = avc_stream_get_format_single(oxfw->unit, dir, pid, buf, len);
506 if (err < 0) {
507 dev_err(&oxfw->unit->device,
508 "fail to get current stream format for isoc %s plug %d:%d\n",
509 (dir == AVC_GENERAL_PLUG_DIR_IN) ? "in" : "out",
510 pid, err);
511 goto end;
512 }
513
514 /* parse and set stream format */
515 eid = 0;
516 err = snd_oxfw_stream_parse_format(buf, &formation);
517 if (err < 0)
518 goto end;
519
520 formats[eid] = kmemdup(buf, *len, GFP_KERNEL);
521 if (formats[eid] == NULL) {
522 err = -ENOMEM;
523 goto end;
524 }
525
526 /* apply the format for each available sampling rate */
527 for (i = 0; i < ARRAY_SIZE(oxfw_rate_table); i++) {
528 if (formation.rate == oxfw_rate_table[i])
529 continue;
530
531 err = avc_general_inquiry_sig_fmt(oxfw->unit,
532 oxfw_rate_table[i],
533 dir, pid);
534 if (err < 0)
535 continue;
536
537 eid++;
538 formats[eid] = kmemdup(buf, *len, GFP_KERNEL);
539 if (formats[eid] == NULL) {
540 err = -ENOMEM;
541 goto end;
542 }
543 formats[eid][2] = avc_stream_rate_table[i];
544 }
545
546 err = 0;
547 oxfw->assumed = true;
548 end:
549 return err;
550 }
551
fill_stream_formats(struct snd_oxfw * oxfw,enum avc_general_plug_dir dir,unsigned short pid)552 static int fill_stream_formats(struct snd_oxfw *oxfw,
553 enum avc_general_plug_dir dir,
554 unsigned short pid)
555 {
556 u8 *buf, **formats;
557 unsigned int len, eid = 0;
558 struct snd_oxfw_stream_formation dummy;
559 int err;
560
561 buf = kmalloc(AVC_GENERIC_FRAME_MAXIMUM_BYTES, GFP_KERNEL);
562 if (buf == NULL)
563 return -ENOMEM;
564
565 if (dir == AVC_GENERAL_PLUG_DIR_OUT)
566 formats = oxfw->tx_stream_formats;
567 else
568 formats = oxfw->rx_stream_formats;
569
570 /* get first entry */
571 len = AVC_GENERIC_FRAME_MAXIMUM_BYTES;
572 err = avc_stream_get_format_list(oxfw->unit, dir, 0, buf, &len, 0);
573 if (err == -ENOSYS) {
574 /* LIST subfunction is not implemented */
575 len = AVC_GENERIC_FRAME_MAXIMUM_BYTES;
576 err = assume_stream_formats(oxfw, dir, pid, buf, &len,
577 formats);
578 goto end;
579 } else if (err < 0) {
580 dev_err(&oxfw->unit->device,
581 "fail to get stream format %d for isoc %s plug %d:%d\n",
582 eid, (dir == AVC_GENERAL_PLUG_DIR_IN) ? "in" : "out",
583 pid, err);
584 goto end;
585 }
586
587 /* LIST subfunction is implemented */
588 while (eid < SND_OXFW_STREAM_FORMAT_ENTRIES) {
589 /* The format is too short. */
590 if (len < 3) {
591 err = -EIO;
592 break;
593 }
594
595 /* parse and set stream format */
596 err = snd_oxfw_stream_parse_format(buf, &dummy);
597 if (err < 0)
598 break;
599
600 formats[eid] = kmemdup(buf, len, GFP_KERNEL);
601 if (formats[eid] == NULL) {
602 err = -ENOMEM;
603 break;
604 }
605
606 /* get next entry */
607 len = AVC_GENERIC_FRAME_MAXIMUM_BYTES;
608 err = avc_stream_get_format_list(oxfw->unit, dir, 0,
609 buf, &len, ++eid);
610 /* No entries remained. */
611 if (err == -EINVAL) {
612 err = 0;
613 break;
614 } else if (err < 0) {
615 dev_err(&oxfw->unit->device,
616 "fail to get stream format %d for isoc %s plug %d:%d\n",
617 eid, (dir == AVC_GENERAL_PLUG_DIR_IN) ? "in" :
618 "out",
619 pid, err);
620 break;
621 }
622 }
623 end:
624 kfree(buf);
625 return err;
626 }
627
snd_oxfw_stream_discover(struct snd_oxfw * oxfw)628 int snd_oxfw_stream_discover(struct snd_oxfw *oxfw)
629 {
630 u8 plugs[AVC_PLUG_INFO_BUF_BYTES];
631 struct snd_oxfw_stream_formation formation;
632 u8 *format;
633 unsigned int i;
634 int err;
635
636 /* the number of plugs for isoc in/out, ext in/out */
637 err = avc_general_get_plug_info(oxfw->unit, 0x1f, 0x07, 0x00, plugs);
638 if (err < 0) {
639 dev_err(&oxfw->unit->device,
640 "fail to get info for isoc/external in/out plugs: %d\n",
641 err);
642 goto end;
643 } else if ((plugs[0] == 0) && (plugs[1] == 0)) {
644 err = -ENOSYS;
645 goto end;
646 }
647
648 /* use oPCR[0] if exists */
649 if (plugs[1] > 0) {
650 err = fill_stream_formats(oxfw, AVC_GENERAL_PLUG_DIR_OUT, 0);
651 if (err < 0)
652 goto end;
653
654 for (i = 0; i < SND_OXFW_STREAM_FORMAT_ENTRIES; i++) {
655 format = oxfw->tx_stream_formats[i];
656 if (format == NULL)
657 continue;
658 err = snd_oxfw_stream_parse_format(format, &formation);
659 if (err < 0)
660 continue;
661
662 /* Add one MIDI port. */
663 if (formation.midi > 0)
664 oxfw->midi_input_ports = 1;
665 }
666
667 oxfw->has_output = true;
668 }
669
670 /* use iPCR[0] if exists */
671 if (plugs[0] > 0) {
672 err = fill_stream_formats(oxfw, AVC_GENERAL_PLUG_DIR_IN, 0);
673 if (err < 0)
674 goto end;
675
676 for (i = 0; i < SND_OXFW_STREAM_FORMAT_ENTRIES; i++) {
677 format = oxfw->rx_stream_formats[i];
678 if (format == NULL)
679 continue;
680 err = snd_oxfw_stream_parse_format(format, &formation);
681 if (err < 0)
682 continue;
683
684 /* Add one MIDI port. */
685 if (formation.midi > 0)
686 oxfw->midi_output_ports = 1;
687 }
688 }
689 end:
690 return err;
691 }
692
snd_oxfw_stream_lock_changed(struct snd_oxfw * oxfw)693 void snd_oxfw_stream_lock_changed(struct snd_oxfw *oxfw)
694 {
695 oxfw->dev_lock_changed = true;
696 wake_up(&oxfw->hwdep_wait);
697 }
698
snd_oxfw_stream_lock_try(struct snd_oxfw * oxfw)699 int snd_oxfw_stream_lock_try(struct snd_oxfw *oxfw)
700 {
701 int err;
702
703 spin_lock_irq(&oxfw->lock);
704
705 /* user land lock this */
706 if (oxfw->dev_lock_count < 0) {
707 err = -EBUSY;
708 goto end;
709 }
710
711 /* this is the first time */
712 if (oxfw->dev_lock_count++ == 0)
713 snd_oxfw_stream_lock_changed(oxfw);
714 err = 0;
715 end:
716 spin_unlock_irq(&oxfw->lock);
717 return err;
718 }
719
snd_oxfw_stream_lock_release(struct snd_oxfw * oxfw)720 void snd_oxfw_stream_lock_release(struct snd_oxfw *oxfw)
721 {
722 spin_lock_irq(&oxfw->lock);
723
724 if (WARN_ON(oxfw->dev_lock_count <= 0))
725 goto end;
726 if (--oxfw->dev_lock_count == 0)
727 snd_oxfw_stream_lock_changed(oxfw);
728 end:
729 spin_unlock_irq(&oxfw->lock);
730 }
731
