master
c 927 lines 24.2 KB
Raw
1 /*
2 * QEMU ALSA audio driver
3 *
4 * Copyright (c) 2005 Vassili Karpov (malc)
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24
25 #include "qemu/osdep.h"
26 #include <alsa/asoundlib.h>
27 #include "qemu/main-loop.h"
28 #include "qemu/module.h"
29 #include "qemu/error-report.h"
30 #include "qemu/audio.h"
31 #include "qom/object.h"
32 #include "trace.h"
33
34 #pragma GCC diagnostic ignored "-Waddress"
35
36 #include "audio_int.h"
37
38 #define TYPE_AUDIO_ALSA "audio-alsa"
39 OBJECT_DECLARE_SIMPLE_TYPE(AudioALSA, AUDIO_ALSA)
40
41 static AudioBackendClass *audio_alsa_parent_class;
42
43 struct AudioALSA {
44 AudioMixengBackend parent_obj;
45 };
46
47
48 struct pollhlp {
49 snd_pcm_t *handle;
50 struct pollfd *pfds;
51 int count;
52 int mask;
53 AudioMixengBackend *s;
54 };
55
56 typedef struct ALSAVoiceOut {
57 HWVoiceOut hw;
58 snd_pcm_t *handle;
59 struct pollhlp pollhlp;
60 } ALSAVoiceOut;
61
62 typedef struct ALSAVoiceIn {
63 HWVoiceIn hw;
64 snd_pcm_t *handle;
65 struct pollhlp pollhlp;
66 } ALSAVoiceIn;
67
68 struct alsa_params_req {
69 int freq;
70 snd_pcm_format_t fmt;
71 int nchannels;
72 };
73
74 struct alsa_params_obt {
75 int freq;
76 AudioFormat fmt;
77 int endianness;
78 int nchannels;
79 snd_pcm_uframes_t samples;
80 };
81
82 static void G_GNUC_PRINTF(2, 3) alsa_logerr(int err, const char *fmt, ...)
83 {
84 va_list ap;
85
86 error_printf("alsa: ");
87 va_start(ap, fmt);
88 error_vprintf(fmt, ap);
89 va_end(ap);
90 error_printf(" Reason: %s", snd_strerror(err));
91 error_printf("\n");
92 }
93
94 static void G_GNUC_PRINTF(3, 4) alsa_logerr2(int err, const char *typ,
95 const char *fmt, ...)
96 {
97 va_list ap;
98
99 error_printf("alsa: Could not initialize %s:", typ);
100 va_start(ap, fmt);
101 error_vprintf(fmt, ap);
102 va_end(ap);
103 error_printf(" Reason: %s", snd_strerror(err));
104 error_printf("\n");
105 }
106
107 static void alsa_fini_poll (struct pollhlp *hlp)
108 {
109 int i;
110 struct pollfd *pfds = hlp->pfds;
111
112 if (pfds) {
113 for (i = 0; i < hlp->count; ++i) {
114 qemu_set_fd_handler (pfds[i].fd, NULL, NULL, NULL);
115 }
116 g_free (pfds);
117 }
118 hlp->pfds = NULL;
119 hlp->count = 0;
120 hlp->handle = NULL;
121 }
122
123 static void alsa_anal_close1 (snd_pcm_t **handlep)
124 {
125 int err = snd_pcm_close (*handlep);
126 if (err) {
127 alsa_logerr(err, "Failed to close PCM handle %p", *handlep);
128 }
129 *handlep = NULL;
130 }
131
132 static void alsa_anal_close (snd_pcm_t **handlep, struct pollhlp *hlp)
133 {
134 alsa_fini_poll (hlp);
135 alsa_anal_close1 (handlep);
136 }
137
138 static int alsa_recover (snd_pcm_t *handle)
139 {
140 int err = snd_pcm_prepare (handle);
141 if (err < 0) {
142 alsa_logerr(err, "Failed to prepare handle %p", handle);
143 return -1;
144 }
145 return 0;
146 }
147
148 static int alsa_resume (snd_pcm_t *handle)
149 {
150 int err = snd_pcm_resume (handle);
151 if (err < 0) {
152 alsa_logerr(err, "Failed to resume handle %p", handle);
153 return -1;
154 }
155 return 0;
156 }
157
158 static void alsa_poll_handler (void *opaque)
159 {
160 int err, count;
161 snd_pcm_state_t state;
162 struct pollhlp *hlp = opaque;
163 unsigned short revents;
164
165 count = poll (hlp->pfds, hlp->count, 0);
166 if (count < 0) {
167 warn_report("alsa_poll_handler: poll %s", strerror(errno));
168 return;
169 }
170
171 if (!count) {
172 return;
173 }
174
175 /* XXX: ALSA example uses initial count, not the one returned by
176 poll, correct? */
177 err = snd_pcm_poll_descriptors_revents (hlp->handle, hlp->pfds,
178 hlp->count, &revents);
179 if (err < 0) {
180 alsa_logerr(err, "snd_pcm_poll_descriptors_revents");
181 return;
182 }
183
184 if (!(revents & hlp->mask)) {
185 trace_alsa_revents(revents);
186 return;
187 }
188
189 state = snd_pcm_state (hlp->handle);
190 switch (state) {
191 case SND_PCM_STATE_SETUP:
192 alsa_recover (hlp->handle);
193 break;
194
195 case SND_PCM_STATE_XRUN:
196 alsa_recover (hlp->handle);
197 break;
198
199 case SND_PCM_STATE_SUSPENDED:
200 alsa_resume (hlp->handle);
201 break;
202
203 case SND_PCM_STATE_PREPARED:
204 audio_run(hlp->s, "alsa run (prepared)");
205 break;
206
207 case SND_PCM_STATE_RUNNING:
208 audio_run(hlp->s, "alsa run (running)");
209 break;
210
211 default:
212 warn_report("alsa: Unexpected state %d", state);
213 }
214 }
215
216 static int alsa_poll_helper (snd_pcm_t *handle, struct pollhlp *hlp, int mask)
217 {
218 int i, count, err;
219 struct pollfd *pfds;
220
221 count = snd_pcm_poll_descriptors_count (handle);
222 if (count <= 0) {
223 warn_report("alsa: Could not initialize poll mode: "
224 "Invalid number of poll descriptors %d", count);
225 return -1;
226 }
227
228 pfds = g_new0(struct pollfd, count);
229
230 err = snd_pcm_poll_descriptors (handle, pfds, count);
231 if (err < 0) {
232 alsa_logerr(err, "Could not initialize poll mode: Could not obtain poll descriptors");
233 g_free (pfds);
234 return -1;
235 }
236
237 for (i = 0; i < count; ++i) {
238 if (pfds[i].events & POLLIN) {
239 qemu_set_fd_handler (pfds[i].fd, alsa_poll_handler, NULL, hlp);
240 }
241 if (pfds[i].events & POLLOUT) {
242 trace_alsa_pollout(i, pfds[i].fd);
243 qemu_set_fd_handler (pfds[i].fd, NULL, alsa_poll_handler, hlp);
244 }
245 trace_alsa_set_handler(pfds[i].events, i, pfds[i].fd, err);
246
247 }
248 hlp->pfds = pfds;
249 hlp->count = count;
250 hlp->handle = handle;
251 hlp->mask = mask;
252 return 0;
253 }
254
255 static int alsa_poll_out (HWVoiceOut *hw)
256 {
257 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
258
259 return alsa_poll_helper (alsa->handle, &alsa->pollhlp, POLLOUT);
260 }
261
262 static int alsa_poll_in (HWVoiceIn *hw)
263 {
264 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
265
266 return alsa_poll_helper (alsa->handle, &alsa->pollhlp, POLLIN);
267 }
268
269 static snd_pcm_format_t aud_to_alsafmt(AudioFormat fmt, bool big_endian)
270 {
271 switch (fmt) {
272 case AUDIO_FORMAT_S8:
273 return SND_PCM_FORMAT_S8;
274
275 case AUDIO_FORMAT_U8:
276 return SND_PCM_FORMAT_U8;
277
278 case AUDIO_FORMAT_S16:
279 return big_endian ? SND_PCM_FORMAT_S16_BE : SND_PCM_FORMAT_S16_LE;
280
281 case AUDIO_FORMAT_U16:
282 return big_endian ? SND_PCM_FORMAT_U16_BE : SND_PCM_FORMAT_U16_LE;
283
284 case AUDIO_FORMAT_S32:
285 return big_endian ? SND_PCM_FORMAT_S32_BE : SND_PCM_FORMAT_S32_LE;
286
287 case AUDIO_FORMAT_U32:
288 return big_endian ? SND_PCM_FORMAT_U32_BE : SND_PCM_FORMAT_U32_LE;
289
290 case AUDIO_FORMAT_F32:
291 return big_endian ? SND_PCM_FORMAT_FLOAT_BE : SND_PCM_FORMAT_FLOAT_LE;
292
293 default:
294 warn_report("alsa: Internal logic error: Bad audio format %d", fmt);
295 return SND_PCM_FORMAT_U8;
296 }
297 }
298
299 static int alsa_to_audfmt (snd_pcm_format_t alsafmt, AudioFormat *fmt,
300 int *endianness)
301 {
302 switch (alsafmt) {
303 case SND_PCM_FORMAT_S8:
304 *endianness = 0;
305 *fmt = AUDIO_FORMAT_S8;
306 break;
307
308 case SND_PCM_FORMAT_U8:
309 *endianness = 0;
310 *fmt = AUDIO_FORMAT_U8;
311 break;
312
313 case SND_PCM_FORMAT_S16_LE:
314 *endianness = 0;
315 *fmt = AUDIO_FORMAT_S16;
316 break;
317
318 case SND_PCM_FORMAT_U16_LE:
319 *endianness = 0;
320 *fmt = AUDIO_FORMAT_U16;
321 break;
322
323 case SND_PCM_FORMAT_S16_BE:
324 *endianness = 1;
325 *fmt = AUDIO_FORMAT_S16;
326 break;
327
328 case SND_PCM_FORMAT_U16_BE:
329 *endianness = 1;
330 *fmt = AUDIO_FORMAT_U16;
331 break;
332
333 case SND_PCM_FORMAT_S32_LE:
334 *endianness = 0;
335 *fmt = AUDIO_FORMAT_S32;
336 break;
337
338 case SND_PCM_FORMAT_U32_LE:
339 *endianness = 0;
340 *fmt = AUDIO_FORMAT_U32;
341 break;
342
343 case SND_PCM_FORMAT_S32_BE:
344 *endianness = 1;
345 *fmt = AUDIO_FORMAT_S32;
346 break;
347
348 case SND_PCM_FORMAT_U32_BE:
349 *endianness = 1;
350 *fmt = AUDIO_FORMAT_U32;
351 break;
352
353 case SND_PCM_FORMAT_FLOAT_LE:
354 *endianness = 0;
355 *fmt = AUDIO_FORMAT_F32;
356 break;
357
358 case SND_PCM_FORMAT_FLOAT_BE:
359 *endianness = 1;
360 *fmt = AUDIO_FORMAT_F32;
361 break;
362
363 default:
364 warn_report("alsa: Unrecognized audio format %d", alsafmt);
365 return -1;
366 }
367
368 return 0;
369 }
370
371 static void alsa_set_threshold (snd_pcm_t *handle, snd_pcm_uframes_t threshold)
372 {
373 int err;
374 snd_pcm_sw_params_t *sw_params;
375
376 snd_pcm_sw_params_alloca (&sw_params);
377
378 err = snd_pcm_sw_params_current (handle, sw_params);
379 if (err < 0) {
380 error_report("alsa: Could not fully initialize DAC");
381 alsa_logerr(err, "Failed to get current software parameters");
382 return;
383 }
384
385 err = snd_pcm_sw_params_set_start_threshold (handle, sw_params, threshold);
386 if (err < 0) {
387 error_report("alsa: Could not fully initialize DAC");
388 alsa_logerr(err, "Failed to set software threshold to %ld", threshold);
389 return;
390 }
391
392 err = snd_pcm_sw_params (handle, sw_params);
393 if (err < 0) {
394 error_report("alsa: Could not fully initialize DAC");
395 alsa_logerr(err, "Failed to set software parameters");
396 return;
397 }
398 }
399
400 static int alsa_open(bool in, struct alsa_params_req *req,
401 struct alsa_params_obt *obt, snd_pcm_t **handlep,
402 Audiodev *dev)
403 {
404 AudiodevAlsaOptions *aopts = &dev->u.alsa;
405 AudiodevAlsaPerDirectionOptions *apdo = in ? aopts->in : aopts->out;
406 snd_pcm_t *handle;
407 snd_pcm_hw_params_t *hw_params;
408 int err;
409 unsigned int freq, nchannels;
410 const char *pcm_name = apdo->dev ?: "default";
411 snd_pcm_uframes_t obt_buffer_size;
412 const char *typ = in ? "ADC" : "DAC";
413 snd_pcm_format_t obtfmt;
414
415 freq = req->freq;
416 nchannels = req->nchannels;
417
418 snd_pcm_hw_params_alloca (&hw_params);
419
420 err = snd_pcm_open (
421 &handle,
422 pcm_name,
423 in ? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK,
424 SND_PCM_NONBLOCK
425 );
426 if (err < 0) {
427 alsa_logerr2(err, typ, "Failed to open `%s'", pcm_name);
428 return -1;
429 }
430
431 err = snd_pcm_hw_params_any (handle, hw_params);
432 if (err < 0) {
433 alsa_logerr2(err, typ, "Failed to initialize hardware parameters");
434 goto err;
435 }
436
437 err = snd_pcm_hw_params_set_access (
438 handle,
439 hw_params,
440 SND_PCM_ACCESS_RW_INTERLEAVED
441 );
442 if (err < 0) {
443 alsa_logerr2(err, typ, "Failed to set access type");
444 goto err;
445 }
446
447 err = snd_pcm_hw_params_set_format (handle, hw_params, req->fmt);
448 if (err < 0) {
449 alsa_logerr2(err, typ, "Failed to set format %d", req->fmt);
450 }
451
452 err = snd_pcm_hw_params_set_rate_near (handle, hw_params, &freq, 0);
453 if (err < 0) {
454 alsa_logerr2(err, typ, "Failed to set frequency %d", req->freq);
455 goto err;
456 }
457
458 err = snd_pcm_hw_params_set_channels_near (
459 handle,
460 hw_params,
461 &nchannels
462 );
463 if (err < 0) {
464 alsa_logerr2(err, typ, "Failed to set number of channels %d", req->nchannels);
465 goto err;
466 }
467
468 if (apdo->buffer_length) {
469 int dir = 0;
470 unsigned int btime = apdo->buffer_length;
471
472 err = snd_pcm_hw_params_set_buffer_time_near(
473 handle, hw_params, &btime, &dir);
474
475 if (err < 0) {
476 alsa_logerr2(err, typ, "Failed to set buffer time to %" PRId32,
477 apdo->buffer_length);
478 goto err;
479 }
480
481 if (apdo->has_buffer_length && btime != apdo->buffer_length) {
482 warn_report("alsa: Requested buffer time %" PRId32 " was rejected, using %u",
483 apdo->buffer_length, btime);
484 }
485 }
486
487 if (apdo->period_length) {
488 int dir = 0;
489 unsigned int ptime = apdo->period_length;
490
491 err = snd_pcm_hw_params_set_period_time_near(handle, hw_params, &ptime,
492 &dir);
493
494 if (err < 0) {
495 alsa_logerr2(err, typ, "Failed to set period time to %" PRId32,
496 apdo->period_length);
497 goto err;
498 }
499
500 if (apdo->has_period_length && ptime != apdo->period_length) {
501 warn_report("alsa: Requested period time %" PRId32 " was rejected, using %d",
502 apdo->period_length, ptime);
503 }
504 }
505
506 err = snd_pcm_hw_params (handle, hw_params);
507 if (err < 0) {
508 alsa_logerr2(err, typ, "Failed to apply audio parameters");
509 goto err;
510 }
511
512 err = snd_pcm_hw_params_get_buffer_size (hw_params, &obt_buffer_size);
513 if (err < 0) {
514 alsa_logerr2(err, typ, "Failed to get buffer size");
515 goto err;
516 }
517
518 err = snd_pcm_hw_params_get_format (hw_params, &obtfmt);
519 if (err < 0) {
520 alsa_logerr2(err, typ, "Failed to get format");
521 goto err;
522 }
523
524 if (alsa_to_audfmt (obtfmt, &obt->fmt, &obt->endianness)) {
525 error_report("alsa: Invalid format was returned %d", obtfmt);
526 goto err;
527 }
528
529 err = snd_pcm_prepare (handle);
530 if (err < 0) {
531 alsa_logerr2(err, typ, "Could not prepare handle %p", handle);
532 goto err;
533 }
534
535 if (!in && aopts->has_threshold && aopts->threshold) {
536 struct audsettings as = { .freq = freq };
537 alsa_set_threshold(
538 handle,
539 audio_buffer_frames(qapi_AudiodevAlsaPerDirectionOptions_base(apdo),
540 &as, aopts->threshold));
541 }
542
543 obt->nchannels = nchannels;
544 obt->freq = freq;
545 obt->samples = obt_buffer_size;
546
547 *handlep = handle;
548
549 trace_alsa_info_params(req->fmt, obtfmt, req->nchannels, obt->nchannels,
550 req->freq, obt->freq);
551 trace_alsa_info_samples(apdo->buffer_length, apdo->period_length, obt->samples);
552
553 return 0;
554
555 err:
556 alsa_anal_close1 (&handle);
557 return -1;
558 }
559
560 static size_t alsa_buffer_get_free(HWVoiceOut *hw)
561 {
562 ALSAVoiceOut *alsa = (ALSAVoiceOut *)hw;
563 snd_pcm_sframes_t avail;
564 size_t alsa_free, generic_free, generic_in_use;
565
566 avail = snd_pcm_avail_update(alsa->handle);
567 if (avail < 0) {
568 if (avail == -EPIPE) {
569 if (!alsa_recover(alsa->handle)) {
570 avail = snd_pcm_avail_update(alsa->handle);
571 }
572 }
573 if (avail < 0) {
574 alsa_logerr(avail, "Could not obtain number of available frames");
575 avail = 0;
576 }
577 }
578
579 alsa_free = avail * hw->info.bytes_per_frame;
580 generic_free = audio_generic_buffer_get_free(hw);
581 generic_in_use = hw->samples * hw->info.bytes_per_frame - generic_free;
582 if (generic_in_use) {
583 /*
584 * This code can only be reached in the unlikely case that
585 * snd_pcm_avail_update() returned a larger number of frames
586 * than snd_pcm_writei() could write. Make sure that all
587 * remaining bytes in the generic buffer can be written.
588 */
589 alsa_free = alsa_free > generic_in_use ? alsa_free - generic_in_use : 0;
590 }
591
592 return alsa_free;
593 }
594
595 static size_t alsa_write(HWVoiceOut *hw, void *buf, size_t len)
596 {
597 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
598 size_t pos = 0;
599 size_t len_frames = len / hw->info.bytes_per_frame;
600
601 while (len_frames) {
602 char *src = advance(buf, pos);
603 snd_pcm_sframes_t written;
604
605 written = snd_pcm_writei(alsa->handle, src, len_frames);
606
607 if (written <= 0) {
608 switch (written) {
609 case 0:
610 trace_alsa_wrote_zero(len_frames);
611 return pos;
612
613 case -EPIPE:
614 if (alsa_recover(alsa->handle)) {
615 alsa_logerr(written, "Failed to write %zu frames", len_frames);
616 return pos;
617 }
618 trace_alsa_xrun_out();
619 continue;
620
621 case -ESTRPIPE:
622 /*
623 * stream is suspended and waiting for an application
624 * recovery
625 */
626 if (alsa_resume(alsa->handle)) {
627 alsa_logerr(written, "Failed to write %zu frames", len_frames);
628 return pos;
629 }
630 trace_alsa_resume_out();
631 continue;
632
633 case -EAGAIN:
634 return pos;
635
636 default:
637 alsa_logerr(written, "Failed to write %zu frames from %p", len_frames, src);
638 return pos;
639 }
640 }
641
642 pos += written * hw->info.bytes_per_frame;
643 if (written < len_frames) {
644 break;
645 }
646 len_frames -= written;
647 }
648
649 return pos;
650 }
651
652 static void alsa_fini_out (HWVoiceOut *hw)
653 {
654 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
655
656 trace_alsa_fini_out();
657 alsa_anal_close (&alsa->handle, &alsa->pollhlp);
658 }
659
660 static int alsa_init_out(HWVoiceOut *hw, struct audsettings *as)
661 {
662 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
663 struct alsa_params_req req;
664 struct alsa_params_obt obt;
665 snd_pcm_t *handle;
666 struct audsettings obt_as;
667 Audiodev *dev = hw->s->dev;
668
669 req.fmt = aud_to_alsafmt (as->fmt, as->big_endian);
670 req.freq = as->freq;
671 req.nchannels = as->nchannels;
672
673 if (alsa_open(0, &req, &obt, &handle, dev)) {
674 return -1;
675 }
676
677 obt_as.freq = obt.freq;
678 obt_as.nchannels = obt.nchannels;
679 obt_as.fmt = obt.fmt;
680 obt_as.big_endian = obt.endianness;
681
682 audio_pcm_init_info (&hw->info, &obt_as);
683 hw->samples = obt.samples;
684
685 alsa->pollhlp.s = hw->s;
686 alsa->handle = handle;
687 return 0;
688 }
689
690 #define VOICE_CTL_PAUSE 0
691 #define VOICE_CTL_PREPARE 1
692 #define VOICE_CTL_START 2
693
694 static int alsa_voice_ctl (snd_pcm_t *handle, const char *typ, int ctl)
695 {
696 int err;
697
698 if (ctl == VOICE_CTL_PAUSE) {
699 err = snd_pcm_drop (handle);
700 if (err < 0) {
701 alsa_logerr(err, "Could not stop %s", typ);
702 return -1;
703 }
704 } else {
705 err = snd_pcm_prepare (handle);
706 if (err < 0) {
707 alsa_logerr(err, "Could not prepare handle for %s", typ);
708 return -1;
709 }
710 if (ctl == VOICE_CTL_START) {
711 err = snd_pcm_start(handle);
712 if (err < 0) {
713 alsa_logerr(err, "Could not start handle for %s", typ);
714 return -1;
715 }
716 }
717 }
718
719 return 0;
720 }
721
722 static void alsa_enable_out(HWVoiceOut *hw, bool enable)
723 {
724 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
725 AudiodevAlsaPerDirectionOptions *apdo = hw->s->dev->u.alsa.out;
726
727 trace_alsa_enable_out(enable);
728
729 if (enable) {
730 bool poll_mode = apdo->try_poll;
731
732 if (poll_mode && alsa_poll_out(hw)) {
733 poll_mode = 0;
734 }
735 hw->poll_mode = poll_mode;
736 alsa_voice_ctl(alsa->handle, "playback", VOICE_CTL_PREPARE);
737 } else {
738 if (hw->poll_mode) {
739 hw->poll_mode = 0;
740 alsa_fini_poll(&alsa->pollhlp);
741 }
742 alsa_voice_ctl(alsa->handle, "playback", VOICE_CTL_PAUSE);
743 }
744 }
745
746 static int alsa_init_in(HWVoiceIn *hw, struct audsettings *as)
747 {
748 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
749 struct alsa_params_req req;
750 struct alsa_params_obt obt;
751 snd_pcm_t *handle;
752 struct audsettings obt_as;
753 Audiodev *dev = hw->s->dev;
754
755 req.fmt = aud_to_alsafmt (as->fmt, as->big_endian);
756 req.freq = as->freq;
757 req.nchannels = as->nchannels;
758
759 if (alsa_open(1, &req, &obt, &handle, dev)) {
760 return -1;
761 }
762
763 obt_as.freq = obt.freq;
764 obt_as.nchannels = obt.nchannels;
765 obt_as.fmt = obt.fmt;
766 obt_as.big_endian = obt.endianness;
767
768 audio_pcm_init_info (&hw->info, &obt_as);
769 hw->samples = obt.samples;
770
771 alsa->pollhlp.s = hw->s;
772 alsa->handle = handle;
773 return 0;
774 }
775
776 static void alsa_fini_in (HWVoiceIn *hw)
777 {
778 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
779
780 alsa_anal_close (&alsa->handle, &alsa->pollhlp);
781 }
782
783 static size_t alsa_read(HWVoiceIn *hw, void *buf, size_t len)
784 {
785 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
786 size_t pos = 0;
787
788 while (len) {
789 void *dst = advance(buf, pos);
790 snd_pcm_sframes_t nread;
791
792 nread = snd_pcm_readi(
793 alsa->handle, dst, len / hw->info.bytes_per_frame);
794
795 if (nread <= 0) {
796 switch (nread) {
797 case 0:
798 trace_alsa_read_zero(len);
799 return pos;
800
801 case -EPIPE:
802 if (alsa_recover(alsa->handle)) {
803 alsa_logerr(nread, "Failed to read %zu frames", len);
804 return pos;
805 }
806 trace_alsa_xrun_in();
807 continue;
808
809 case -EAGAIN:
810 return pos;
811
812 default:
813 alsa_logerr(nread, "Failed to read %zu frames to %p", len, dst);
814 return pos;
815 }
816 }
817
818 pos += nread * hw->info.bytes_per_frame;
819 len -= nread * hw->info.bytes_per_frame;
820 }
821
822 return pos;
823 }
824
825 static void alsa_enable_in(HWVoiceIn *hw, bool enable)
826 {
827 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
828 AudiodevAlsaPerDirectionOptions *apdo = hw->s->dev->u.alsa.in;
829
830 trace_alsa_enable_in(enable);
831
832 if (enable) {
833 bool poll_mode = apdo->try_poll;
834
835 if (poll_mode && alsa_poll_in(hw)) {
836 poll_mode = 0;
837 }
838 hw->poll_mode = poll_mode;
839
840 alsa_voice_ctl(alsa->handle, "capture", VOICE_CTL_START);
841 } else {
842 if (hw->poll_mode) {
843 hw->poll_mode = 0;
844 alsa_fini_poll(&alsa->pollhlp);
845 }
846 alsa_voice_ctl(alsa->handle, "capture", VOICE_CTL_PAUSE);
847 }
848 }
849
850 static void alsa_init_per_direction(AudiodevAlsaPerDirectionOptions *apdo)
851 {
852 if (!apdo->has_try_poll) {
853 apdo->try_poll = false;
854 apdo->has_try_poll = true;
855 }
856 }
857
858 static bool
859 audio_alsa_realize(AudioBackend *abe, Audiodev *dev, Error **errp)
860 {
861 AudiodevAlsaOptions *aopts;
862 assert(dev->driver == AUDIODEV_DRIVER_ALSA);
863
864 aopts = &dev->u.alsa;
865 alsa_init_per_direction(aopts->in);
866 alsa_init_per_direction(aopts->out);
867
868 /* don't set has_* so alsa_open can identify it wasn't set by the user */
869 if (!dev->u.alsa.out->has_period_length) {
870 /* 256 frames assuming 44100Hz */
871 dev->u.alsa.out->period_length = 5805;
872 }
873 if (!dev->u.alsa.out->has_buffer_length) {
874 /* 4096 frames assuming 44100Hz */
875 dev->u.alsa.out->buffer_length = 92880;
876 }
877
878 if (!dev->u.alsa.in->has_period_length) {
879 /* 256 frames assuming 44100Hz */
880 dev->u.alsa.in->period_length = 5805;
881 }
882 if (!dev->u.alsa.in->has_buffer_length) {
883 /* 4096 frames assuming 44100Hz */
884 dev->u.alsa.in->buffer_length = 92880;
885 }
886
887 return audio_alsa_parent_class->realize(abe, dev, errp);
888 }
889
890 static void audio_alsa_class_init(ObjectClass *klass, const void *data)
891 {
892 AudioBackendClass *b = AUDIO_BACKEND_CLASS(klass);
893 AudioMixengBackendClass *k = AUDIO_MIXENG_BACKEND_CLASS(klass);
894
895 audio_alsa_parent_class = AUDIO_BACKEND_CLASS(object_class_get_parent(klass));
896
897 b->realize = audio_alsa_realize;
898 k->max_voices_out = INT_MAX;
899 k->max_voices_in = INT_MAX;
900 k->voice_size_out = sizeof(ALSAVoiceOut);
901 k->voice_size_in = sizeof(ALSAVoiceIn);
902
903 k->init_out = alsa_init_out;
904 k->fini_out = alsa_fini_out;
905 k->write = alsa_write;
906 k->buffer_get_free = alsa_buffer_get_free;
907 k->run_buffer_out = audio_generic_run_buffer_out;
908 k->enable_out = alsa_enable_out;
909
910 k->init_in = alsa_init_in;
911 k->fini_in = alsa_fini_in;
912 k->read = alsa_read;
913 k->run_buffer_in = audio_generic_run_buffer_in;
914 k->enable_in = alsa_enable_in;
915 }
916
917 static const TypeInfo audio_types[] = {
918 {
919 .name = TYPE_AUDIO_ALSA,
920 .parent = TYPE_AUDIO_MIXENG_BACKEND,
921 .instance_size = sizeof(AudioALSA),
922 .class_init = audio_alsa_class_init,
923 },
924 };
925
926 DEFINE_TYPES(audio_types)
927 module_obj(TYPE_AUDIO_ALSA);