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25#include "qemu/osdep.h"
26#include <alsa/asoundlib.h>
27#include "qemu/main-loop.h"
28#include "qemu/module.h"
29#include "audio.h"
30#include "trace.h"
31
32#pragma GCC diagnostic ignored "-Waddress"
33
34#define AUDIO_CAP "alsa"
35#include "audio_int.h"
36
37#define DEBUG_ALSA 0
38
39struct pollhlp {
40 snd_pcm_t *handle;
41 struct pollfd *pfds;
42 int count;
43 int mask;
44 AudioState *s;
45};
46
47typedef struct ALSAVoiceOut {
48 HWVoiceOut hw;
49 snd_pcm_t *handle;
50 struct pollhlp pollhlp;
51 Audiodev *dev;
52} ALSAVoiceOut;
53
54typedef struct ALSAVoiceIn {
55 HWVoiceIn hw;
56 snd_pcm_t *handle;
57 struct pollhlp pollhlp;
58 Audiodev *dev;
59} ALSAVoiceIn;
60
61struct alsa_params_req {
62 int freq;
63 snd_pcm_format_t fmt;
64 int nchannels;
65};
66
67struct alsa_params_obt {
68 int freq;
69 AudioFormat fmt;
70 int endianness;
71 int nchannels;
72 snd_pcm_uframes_t samples;
73};
74
75static void G_GNUC_PRINTF (2, 3) alsa_logerr (int err, const char *fmt, ...)
76{
77 va_list ap;
78
79 va_start (ap, fmt);
80 AUD_vlog (AUDIO_CAP, fmt, ap);
81 va_end (ap);
82
83 AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
84}
85
86static void G_GNUC_PRINTF (3, 4) alsa_logerr2 (
87 int err,
88 const char *typ,
89 const char *fmt,
90 ...
91 )
92{
93 va_list ap;
94
95 AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
96
97 va_start (ap, fmt);
98 AUD_vlog (AUDIO_CAP, fmt, ap);
99 va_end (ap);
100
101 AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
102}
103
104static void alsa_fini_poll (struct pollhlp *hlp)
105{
106 int i;
107 struct pollfd *pfds = hlp->pfds;
108
109 if (pfds) {
110 for (i = 0; i < hlp->count; ++i) {
111 qemu_set_fd_handler (pfds[i].fd, NULL, NULL, NULL);
112 }
113 g_free (pfds);
114 }
115 hlp->pfds = NULL;
116 hlp->count = 0;
117 hlp->handle = NULL;
118}
119
120static void alsa_anal_close1 (snd_pcm_t **handlep)
121{
122 int err = snd_pcm_close (*handlep);
123 if (err) {
124 alsa_logerr (err, "Failed to close PCM handle %p\n", *handlep);
125 }
126 *handlep = NULL;
127}
128
129static void alsa_anal_close (snd_pcm_t **handlep, struct pollhlp *hlp)
130{
131 alsa_fini_poll (hlp);
132 alsa_anal_close1 (handlep);
133}
134
135static int alsa_recover (snd_pcm_t *handle)
136{
137 int err = snd_pcm_prepare (handle);
138 if (err < 0) {
139 alsa_logerr (err, "Failed to prepare handle %p\n", handle);
140 return -1;
141 }
142 return 0;
143}
144
145static int alsa_resume (snd_pcm_t *handle)
146{
147 int err = snd_pcm_resume (handle);
148 if (err < 0) {
149 alsa_logerr (err, "Failed to resume handle %p\n", handle);
150 return -1;
151 }
152 return 0;
153}
154
155static void alsa_poll_handler (void *opaque)
156{
157 int err, count;
158 snd_pcm_state_t state;
159 struct pollhlp *hlp = opaque;
160 unsigned short revents;
161
162 count = poll (hlp->pfds, hlp->count, 0);
163 if (count < 0) {
164 dolog ("alsa_poll_handler: poll %s\n", strerror (errno));
165 return;
166 }
167
168 if (!count) {
169 return;
170 }
171
172
173
174 err = snd_pcm_poll_descriptors_revents (hlp->handle, hlp->pfds,
175 hlp->count, &revents);
176 if (err < 0) {
177 alsa_logerr (err, "snd_pcm_poll_descriptors_revents");
178 return;
179 }
180
181 if (!(revents & hlp->mask)) {
182 trace_alsa_revents(revents);
183 return;
184 }
185
186 state = snd_pcm_state (hlp->handle);
187 switch (state) {
188 case SND_PCM_STATE_SETUP:
189 alsa_recover (hlp->handle);
190 break;
191
192 case SND_PCM_STATE_XRUN:
193 alsa_recover (hlp->handle);
194 break;
195
196 case SND_PCM_STATE_SUSPENDED:
197 alsa_resume (hlp->handle);
198 break;
199
200 case SND_PCM_STATE_PREPARED:
201 audio_run(hlp->s, "alsa run (prepared)");
202 break;
203
204 case SND_PCM_STATE_RUNNING:
205 audio_run(hlp->s, "alsa run (running)");
206 break;
207
208 default:
209 dolog ("Unexpected state %d\n", state);
210 }
211}
212
213static int alsa_poll_helper (snd_pcm_t *handle, struct pollhlp *hlp, int mask)
214{
215 int i, count, err;
216 struct pollfd *pfds;
217
218 count = snd_pcm_poll_descriptors_count (handle);
219 if (count <= 0) {
220 dolog ("Could not initialize poll mode\n"
221 "Invalid number of poll descriptors %d\n", count);
222 return -1;
223 }
224
225 pfds = g_new0(struct pollfd, count);
226
227 err = snd_pcm_poll_descriptors (handle, pfds, count);
228 if (err < 0) {
229 alsa_logerr (err, "Could not initialize poll mode\n"
230 "Could not obtain poll descriptors\n");
231 g_free (pfds);
232 return -1;
233 }
234
235 for (i = 0; i < count; ++i) {
236 if (pfds[i].events & POLLIN) {
237 qemu_set_fd_handler (pfds[i].fd, alsa_poll_handler, NULL, hlp);
238 }
239 if (pfds[i].events & POLLOUT) {
240 trace_alsa_pollout(i, pfds[i].fd);
241 qemu_set_fd_handler (pfds[i].fd, NULL, alsa_poll_handler, hlp);
242 }
243 trace_alsa_set_handler(pfds[i].events, i, pfds[i].fd, err);
244
245 }
246 hlp->pfds = pfds;
247 hlp->count = count;
248 hlp->handle = handle;
249 hlp->mask = mask;
250 return 0;
251}
252
253static int alsa_poll_out (HWVoiceOut *hw)
254{
255 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
256
257 return alsa_poll_helper (alsa->handle, &alsa->pollhlp, POLLOUT);
258}
259
260static int alsa_poll_in (HWVoiceIn *hw)
261{
262 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
263
264 return alsa_poll_helper (alsa->handle, &alsa->pollhlp, POLLIN);
265}
266
267static snd_pcm_format_t aud_to_alsafmt (AudioFormat fmt, int endianness)
268{
269 switch (fmt) {
270 case AUDIO_FORMAT_S8:
271 return SND_PCM_FORMAT_S8;
272
273 case AUDIO_FORMAT_U8:
274 return SND_PCM_FORMAT_U8;
275
276 case AUDIO_FORMAT_S16:
277 if (endianness) {
278 return SND_PCM_FORMAT_S16_BE;
279 } else {
280 return SND_PCM_FORMAT_S16_LE;
281 }
282
283 case AUDIO_FORMAT_U16:
284 if (endianness) {
285 return SND_PCM_FORMAT_U16_BE;
286 } else {
287 return SND_PCM_FORMAT_U16_LE;
288 }
289
290 case AUDIO_FORMAT_S32:
291 if (endianness) {
292 return SND_PCM_FORMAT_S32_BE;
293 } else {
294 return SND_PCM_FORMAT_S32_LE;
295 }
296
297 case AUDIO_FORMAT_U32:
298 if (endianness) {
299 return SND_PCM_FORMAT_U32_BE;
300 } else {
301 return SND_PCM_FORMAT_U32_LE;
302 }
303
304 case AUDIO_FORMAT_F32:
305 if (endianness) {
306 return SND_PCM_FORMAT_FLOAT_BE;
307 } else {
308 return SND_PCM_FORMAT_FLOAT_LE;
309 }
310
311 default:
312 dolog ("Internal logic error: Bad audio format %d\n", fmt);
313#ifdef DEBUG_AUDIO
314 abort ();
315#endif
316 return SND_PCM_FORMAT_U8;
317 }
318}
319
320static int alsa_to_audfmt (snd_pcm_format_t alsafmt, AudioFormat *fmt,
321 int *endianness)
322{
323 switch (alsafmt) {
324 case SND_PCM_FORMAT_S8:
325 *endianness = 0;
326 *fmt = AUDIO_FORMAT_S8;
327 break;
328
329 case SND_PCM_FORMAT_U8:
330 *endianness = 0;
331 *fmt = AUDIO_FORMAT_U8;
332 break;
333
334 case SND_PCM_FORMAT_S16_LE:
335 *endianness = 0;
336 *fmt = AUDIO_FORMAT_S16;
337 break;
338
339 case SND_PCM_FORMAT_U16_LE:
340 *endianness = 0;
341 *fmt = AUDIO_FORMAT_U16;
342 break;
343
344 case SND_PCM_FORMAT_S16_BE:
345 *endianness = 1;
346 *fmt = AUDIO_FORMAT_S16;
347 break;
348
349 case SND_PCM_FORMAT_U16_BE:
350 *endianness = 1;
351 *fmt = AUDIO_FORMAT_U16;
352 break;
353
354 case SND_PCM_FORMAT_S32_LE:
355 *endianness = 0;
356 *fmt = AUDIO_FORMAT_S32;
357 break;
358
359 case SND_PCM_FORMAT_U32_LE:
360 *endianness = 0;
361 *fmt = AUDIO_FORMAT_U32;
362 break;
363
364 case SND_PCM_FORMAT_S32_BE:
365 *endianness = 1;
366 *fmt = AUDIO_FORMAT_S32;
367 break;
368
369 case SND_PCM_FORMAT_U32_BE:
370 *endianness = 1;
371 *fmt = AUDIO_FORMAT_U32;
372 break;
373
374 case SND_PCM_FORMAT_FLOAT_LE:
375 *endianness = 0;
376 *fmt = AUDIO_FORMAT_F32;
377 break;
378
379 case SND_PCM_FORMAT_FLOAT_BE:
380 *endianness = 1;
381 *fmt = AUDIO_FORMAT_F32;
382 break;
383
384 default:
385 dolog ("Unrecognized audio format %d\n", alsafmt);
386 return -1;
387 }
388
389 return 0;
390}
391
392static void alsa_dump_info (struct alsa_params_req *req,
393 struct alsa_params_obt *obt,
394 snd_pcm_format_t obtfmt,
395 AudiodevAlsaPerDirectionOptions *apdo)
396{
397 dolog("parameter | requested value | obtained value\n");
398 dolog("format | %10d | %10d\n", req->fmt, obtfmt);
399 dolog("channels | %10d | %10d\n",
400 req->nchannels, obt->nchannels);
401 dolog("frequency | %10d | %10d\n", req->freq, obt->freq);
402 dolog("============================================\n");
403 dolog("requested: buffer len %" PRId32 " period len %" PRId32 "\n",
404 apdo->buffer_length, apdo->period_length);
405 dolog("obtained: samples %ld\n", obt->samples);
406}
407
408static void alsa_set_threshold (snd_pcm_t *handle, snd_pcm_uframes_t threshold)
409{
410 int err;
411 snd_pcm_sw_params_t *sw_params;
412
413 snd_pcm_sw_params_alloca (&sw_params);
414
415 err = snd_pcm_sw_params_current (handle, sw_params);
416 if (err < 0) {
417 dolog ("Could not fully initialize DAC\n");
418 alsa_logerr (err, "Failed to get current software parameters\n");
419 return;
420 }
421
422 err = snd_pcm_sw_params_set_start_threshold (handle, sw_params, threshold);
423 if (err < 0) {
424 dolog ("Could not fully initialize DAC\n");
425 alsa_logerr (err, "Failed to set software threshold to %ld\n",
426 threshold);
427 return;
428 }
429
430 err = snd_pcm_sw_params (handle, sw_params);
431 if (err < 0) {
432 dolog ("Could not fully initialize DAC\n");
433 alsa_logerr (err, "Failed to set software parameters\n");
434 return;
435 }
436}
437
438static int alsa_open(bool in, struct alsa_params_req *req,
439 struct alsa_params_obt *obt, snd_pcm_t **handlep,
440 Audiodev *dev)
441{
442 AudiodevAlsaOptions *aopts = &dev->u.alsa;
443 AudiodevAlsaPerDirectionOptions *apdo = in ? aopts->in : aopts->out;
444 snd_pcm_t *handle;
445 snd_pcm_hw_params_t *hw_params;
446 int err;
447 unsigned int freq, nchannels;
448 const char *pcm_name = apdo->dev ?: "default";
449 snd_pcm_uframes_t obt_buffer_size;
450 const char *typ = in ? "ADC" : "DAC";
451 snd_pcm_format_t obtfmt;
452
453 freq = req->freq;
454 nchannels = req->nchannels;
455
456 snd_pcm_hw_params_alloca (&hw_params);
457
458 err = snd_pcm_open (
459 &handle,
460 pcm_name,
461 in ? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK,
462 SND_PCM_NONBLOCK
463 );
464 if (err < 0) {
465 alsa_logerr2 (err, typ, "Failed to open `%s':\n", pcm_name);
466 return -1;
467 }
468
469 err = snd_pcm_hw_params_any (handle, hw_params);
470 if (err < 0) {
471 alsa_logerr2 (err, typ, "Failed to initialize hardware parameters\n");
472 goto err;
473 }
474
475 err = snd_pcm_hw_params_set_access (
476 handle,
477 hw_params,
478 SND_PCM_ACCESS_RW_INTERLEAVED
479 );
480 if (err < 0) {
481 alsa_logerr2 (err, typ, "Failed to set access type\n");
482 goto err;
483 }
484
485 err = snd_pcm_hw_params_set_format (handle, hw_params, req->fmt);
486 if (err < 0) {
487 alsa_logerr2 (err, typ, "Failed to set format %d\n", req->fmt);
488 }
489
490 err = snd_pcm_hw_params_set_rate_near (handle, hw_params, &freq, 0);
491 if (err < 0) {
492 alsa_logerr2 (err, typ, "Failed to set frequency %d\n", req->freq);
493 goto err;
494 }
495
496 err = snd_pcm_hw_params_set_channels_near (
497 handle,
498 hw_params,
499 &nchannels
500 );
501 if (err < 0) {
502 alsa_logerr2 (err, typ, "Failed to set number of channels %d\n",
503 req->nchannels);
504 goto err;
505 }
506
507 if (apdo->buffer_length) {
508 int dir = 0;
509 unsigned int btime = apdo->buffer_length;
510
511 err = snd_pcm_hw_params_set_buffer_time_near(
512 handle, hw_params, &btime, &dir);
513
514 if (err < 0) {
515 alsa_logerr2(err, typ, "Failed to set buffer time to %" PRId32 "\n",
516 apdo->buffer_length);
517 goto err;
518 }
519
520 if (apdo->has_buffer_length && btime != apdo->buffer_length) {
521 dolog("Requested buffer time %" PRId32
522 " was rejected, using %u\n", apdo->buffer_length, btime);
523 }
524 }
525
526 if (apdo->period_length) {
527 int dir = 0;
528 unsigned int ptime = apdo->period_length;
529
530 err = snd_pcm_hw_params_set_period_time_near(handle, hw_params, &ptime,
531 &dir);
532
533 if (err < 0) {
534 alsa_logerr2(err, typ, "Failed to set period time to %" PRId32 "\n",
535 apdo->period_length);
536 goto err;
537 }
538
539 if (apdo->has_period_length && ptime != apdo->period_length) {
540 dolog("Requested period time %" PRId32 " was rejected, using %d\n",
541 apdo->period_length, ptime);
542 }
543 }
544
545 err = snd_pcm_hw_params (handle, hw_params);
546 if (err < 0) {
547 alsa_logerr2 (err, typ, "Failed to apply audio parameters\n");
548 goto err;
549 }
550
551 err = snd_pcm_hw_params_get_buffer_size (hw_params, &obt_buffer_size);
552 if (err < 0) {
553 alsa_logerr2 (err, typ, "Failed to get buffer size\n");
554 goto err;
555 }
556
557 err = snd_pcm_hw_params_get_format (hw_params, &obtfmt);
558 if (err < 0) {
559 alsa_logerr2 (err, typ, "Failed to get format\n");
560 goto err;
561 }
562
563 if (alsa_to_audfmt (obtfmt, &obt->fmt, &obt->endianness)) {
564 dolog ("Invalid format was returned %d\n", obtfmt);
565 goto err;
566 }
567
568 err = snd_pcm_prepare (handle);
569 if (err < 0) {
570 alsa_logerr2 (err, typ, "Could not prepare handle %p\n", handle);
571 goto err;
572 }
573
574 if (!in && aopts->has_threshold && aopts->threshold) {
575 struct audsettings as = { .freq = freq };
576 alsa_set_threshold(
577 handle,
578 audio_buffer_frames(qapi_AudiodevAlsaPerDirectionOptions_base(apdo),
579 &as, aopts->threshold));
580 }
581
582 obt->nchannels = nchannels;
583 obt->freq = freq;
584 obt->samples = obt_buffer_size;
585
586 *handlep = handle;
587
588 if (DEBUG_ALSA || obtfmt != req->fmt ||
589 obt->nchannels != req->nchannels || obt->freq != req->freq) {
590 dolog ("Audio parameters for %s\n", typ);
591 alsa_dump_info(req, obt, obtfmt, apdo);
592 }
593
594 return 0;
595
596 err:
597 alsa_anal_close1 (&handle);
598 return -1;
599}
600
601static size_t alsa_buffer_get_free(HWVoiceOut *hw)
602{
603 ALSAVoiceOut *alsa = (ALSAVoiceOut *)hw;
604 snd_pcm_sframes_t avail;
605 size_t alsa_free, generic_free, generic_in_use;
606
607 avail = snd_pcm_avail_update(alsa->handle);
608 if (avail < 0) {
609 if (avail == -EPIPE) {
610 if (!alsa_recover(alsa->handle)) {
611 avail = snd_pcm_avail_update(alsa->handle);
612 }
613 }
614 if (avail < 0) {
615 alsa_logerr(avail,
616 "Could not obtain number of available frames\n");
617 avail = 0;
618 }
619 }
620
621 alsa_free = avail * hw->info.bytes_per_frame;
622 generic_free = audio_generic_buffer_get_free(hw);
623 generic_in_use = hw->samples * hw->info.bytes_per_frame - generic_free;
624 if (generic_in_use) {
625
626
627
628
629
630
631 alsa_free = alsa_free > generic_in_use ? alsa_free - generic_in_use : 0;
632 }
633
634 return alsa_free;
635}
636
637static size_t alsa_write(HWVoiceOut *hw, void *buf, size_t len)
638{
639 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
640 size_t pos = 0;
641 size_t len_frames = len / hw->info.bytes_per_frame;
642
643 while (len_frames) {
644 char *src = advance(buf, pos);
645 snd_pcm_sframes_t written;
646
647 written = snd_pcm_writei(alsa->handle, src, len_frames);
648
649 if (written <= 0) {
650 switch (written) {
651 case 0:
652 trace_alsa_wrote_zero(len_frames);
653 return pos;
654
655 case -EPIPE:
656 if (alsa_recover(alsa->handle)) {
657 alsa_logerr(written, "Failed to write %zu frames\n",
658 len_frames);
659 return pos;
660 }
661 trace_alsa_xrun_out();
662 continue;
663
664 case -ESTRPIPE:
665
666
667
668
669 if (alsa_resume(alsa->handle)) {
670 alsa_logerr(written, "Failed to write %zu frames\n",
671 len_frames);
672 return pos;
673 }
674 trace_alsa_resume_out();
675 continue;
676
677 case -EAGAIN:
678 return pos;
679
680 default:
681 alsa_logerr(written, "Failed to write %zu frames from %p\n",
682 len, src);
683 return pos;
684 }
685 }
686
687 pos += written * hw->info.bytes_per_frame;
688 if (written < len_frames) {
689 break;
690 }
691 len_frames -= written;
692 }
693
694 return pos;
695}
696
697static void alsa_fini_out (HWVoiceOut *hw)
698{
699 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
700
701 ldebug ("alsa_fini\n");
702 alsa_anal_close (&alsa->handle, &alsa->pollhlp);
703}
704
705static int alsa_init_out(HWVoiceOut *hw, struct audsettings *as,
706 void *drv_opaque)
707{
708 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
709 struct alsa_params_req req;
710 struct alsa_params_obt obt;
711 snd_pcm_t *handle;
712 struct audsettings obt_as;
713 Audiodev *dev = drv_opaque;
714
715 req.fmt = aud_to_alsafmt (as->fmt, as->endianness);
716 req.freq = as->freq;
717 req.nchannels = as->nchannels;
718
719 if (alsa_open(0, &req, &obt, &handle, dev)) {
720 return -1;
721 }
722
723 obt_as.freq = obt.freq;
724 obt_as.nchannels = obt.nchannels;
725 obt_as.fmt = obt.fmt;
726 obt_as.endianness = obt.endianness;
727
728 audio_pcm_init_info (&hw->info, &obt_as);
729 hw->samples = obt.samples;
730
731 alsa->pollhlp.s = hw->s;
732 alsa->handle = handle;
733 alsa->dev = dev;
734 return 0;
735}
736
737#define VOICE_CTL_PAUSE 0
738#define VOICE_CTL_PREPARE 1
739#define VOICE_CTL_START 2
740
741static int alsa_voice_ctl (snd_pcm_t *handle, const char *typ, int ctl)
742{
743 int err;
744
745 if (ctl == VOICE_CTL_PAUSE) {
746 err = snd_pcm_drop (handle);
747 if (err < 0) {
748 alsa_logerr (err, "Could not stop %s\n", typ);
749 return -1;
750 }
751 } else {
752 err = snd_pcm_prepare (handle);
753 if (err < 0) {
754 alsa_logerr (err, "Could not prepare handle for %s\n", typ);
755 return -1;
756 }
757 if (ctl == VOICE_CTL_START) {
758 err = snd_pcm_start(handle);
759 if (err < 0) {
760 alsa_logerr (err, "Could not start handle for %s\n", typ);
761 return -1;
762 }
763 }
764 }
765
766 return 0;
767}
768
769static void alsa_enable_out(HWVoiceOut *hw, bool enable)
770{
771 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
772 AudiodevAlsaPerDirectionOptions *apdo = alsa->dev->u.alsa.out;
773
774 if (enable) {
775 bool poll_mode = apdo->try_poll;
776
777 ldebug("enabling voice\n");
778 if (poll_mode && alsa_poll_out(hw)) {
779 poll_mode = 0;
780 }
781 hw->poll_mode = poll_mode;
782 alsa_voice_ctl(alsa->handle, "playback", VOICE_CTL_PREPARE);
783 } else {
784 ldebug("disabling voice\n");
785 if (hw->poll_mode) {
786 hw->poll_mode = 0;
787 alsa_fini_poll(&alsa->pollhlp);
788 }
789 alsa_voice_ctl(alsa->handle, "playback", VOICE_CTL_PAUSE);
790 }
791}
792
793static int alsa_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque)
794{
795 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
796 struct alsa_params_req req;
797 struct alsa_params_obt obt;
798 snd_pcm_t *handle;
799 struct audsettings obt_as;
800 Audiodev *dev = drv_opaque;
801
802 req.fmt = aud_to_alsafmt (as->fmt, as->endianness);
803 req.freq = as->freq;
804 req.nchannels = as->nchannels;
805
806 if (alsa_open(1, &req, &obt, &handle, dev)) {
807 return -1;
808 }
809
810 obt_as.freq = obt.freq;
811 obt_as.nchannels = obt.nchannels;
812 obt_as.fmt = obt.fmt;
813 obt_as.endianness = obt.endianness;
814
815 audio_pcm_init_info (&hw->info, &obt_as);
816 hw->samples = obt.samples;
817
818 alsa->pollhlp.s = hw->s;
819 alsa->handle = handle;
820 alsa->dev = dev;
821 return 0;
822}
823
824static void alsa_fini_in (HWVoiceIn *hw)
825{
826 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
827
828 alsa_anal_close (&alsa->handle, &alsa->pollhlp);
829}
830
831static size_t alsa_read(HWVoiceIn *hw, void *buf, size_t len)
832{
833 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
834 size_t pos = 0;
835
836 while (len) {
837 void *dst = advance(buf, pos);
838 snd_pcm_sframes_t nread;
839
840 nread = snd_pcm_readi(
841 alsa->handle, dst, len / hw->info.bytes_per_frame);
842
843 if (nread <= 0) {
844 switch (nread) {
845 case 0:
846 trace_alsa_read_zero(len);
847 return pos;
848
849 case -EPIPE:
850 if (alsa_recover(alsa->handle)) {
851 alsa_logerr(nread, "Failed to read %zu frames\n", len);
852 return pos;
853 }
854 trace_alsa_xrun_in();
855 continue;
856
857 case -EAGAIN:
858 return pos;
859
860 default:
861 alsa_logerr(nread, "Failed to read %zu frames to %p\n",
862 len, dst);
863 return pos;
864 }
865 }
866
867 pos += nread * hw->info.bytes_per_frame;
868 len -= nread * hw->info.bytes_per_frame;
869 }
870
871 return pos;
872}
873
874static void alsa_enable_in(HWVoiceIn *hw, bool enable)
875{
876 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
877 AudiodevAlsaPerDirectionOptions *apdo = alsa->dev->u.alsa.in;
878
879 if (enable) {
880 bool poll_mode = apdo->try_poll;
881
882 ldebug("enabling voice\n");
883 if (poll_mode && alsa_poll_in(hw)) {
884 poll_mode = 0;
885 }
886 hw->poll_mode = poll_mode;
887
888 alsa_voice_ctl(alsa->handle, "capture", VOICE_CTL_START);
889 } else {
890 ldebug ("disabling voice\n");
891 if (hw->poll_mode) {
892 hw->poll_mode = 0;
893 alsa_fini_poll(&alsa->pollhlp);
894 }
895 alsa_voice_ctl(alsa->handle, "capture", VOICE_CTL_PAUSE);
896 }
897}
898
899static void alsa_init_per_direction(AudiodevAlsaPerDirectionOptions *apdo)
900{
901 if (!apdo->has_try_poll) {
902 apdo->try_poll = false;
903 apdo->has_try_poll = true;
904 }
905}
906
907static void *alsa_audio_init(Audiodev *dev, Error **errp)
908{
909 AudiodevAlsaOptions *aopts;
910 assert(dev->driver == AUDIODEV_DRIVER_ALSA);
911
912 aopts = &dev->u.alsa;
913 alsa_init_per_direction(aopts->in);
914 alsa_init_per_direction(aopts->out);
915
916
917 if (!dev->u.alsa.out->has_period_length) {
918
919 dev->u.alsa.out->period_length = 5805;
920 }
921 if (!dev->u.alsa.out->has_buffer_length) {
922
923 dev->u.alsa.out->buffer_length = 92880;
924 }
925
926 if (!dev->u.alsa.in->has_period_length) {
927
928 dev->u.alsa.in->period_length = 5805;
929 }
930 if (!dev->u.alsa.in->has_buffer_length) {
931
932 dev->u.alsa.in->buffer_length = 92880;
933 }
934
935 return dev;
936}
937
938static void alsa_audio_fini (void *opaque)
939{
940}
941
942static struct audio_pcm_ops alsa_pcm_ops = {
943 .init_out = alsa_init_out,
944 .fini_out = alsa_fini_out,
945 .write = alsa_write,
946 .buffer_get_free = alsa_buffer_get_free,
947 .run_buffer_out = audio_generic_run_buffer_out,
948 .enable_out = alsa_enable_out,
949
950 .init_in = alsa_init_in,
951 .fini_in = alsa_fini_in,
952 .read = alsa_read,
953 .run_buffer_in = audio_generic_run_buffer_in,
954 .enable_in = alsa_enable_in,
955};
956
957static struct audio_driver alsa_audio_driver = {
958 .name = "alsa",
959 .descr = "ALSA http://www.alsa-project.org",
960 .init = alsa_audio_init,
961 .fini = alsa_audio_fini,
962 .pcm_ops = &alsa_pcm_ops,
963 .max_voices_out = INT_MAX,
964 .max_voices_in = INT_MAX,
965 .voice_size_out = sizeof (ALSAVoiceOut),
966 .voice_size_in = sizeof (ALSAVoiceIn)
967};
968
969static void register_audio_alsa(void)
970{
971 audio_driver_register(&alsa_audio_driver);
972}
973type_init(register_audio_alsa);
974
