alsaaudio.c@ 2564

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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	#include <alsa/asoundlib.h>
25
26	#include "Builtins.h"
27	#include "../../vl_vbox.h"
28	#include "audio.h"
29	#include <iprt/alloc.h>
30
31	#define AUDIO_CAP "alsa"
32	#include "audio_int.h"
33
34	typedef struct ALSAVoiceOut {
35	HWVoiceOut hw;
36	void *pcm_buf;
37	snd_pcm_t *handle;
38	} ALSAVoiceOut;
39
40	typedef struct ALSAVoiceIn {
41	HWVoiceIn hw;
42	snd_pcm_t *handle;
43	void *pcm_buf;
44	} ALSAVoiceIn;
45
46	/* latency = period_size * periods / (rate * bytes_per_frame) */
47
48	static struct {
49	int size_in_usec_in;
50	int size_in_usec_out;
51	const char *pcm_name_in;
52	const char *pcm_name_out;
53	unsigned int buffer_size_in;
54	unsigned int period_size_in;
55	unsigned int buffer_size_out;
56	unsigned int period_size_out;
57	unsigned int threshold;
58
59	int buffer_size_in_overriden;
60	int period_size_in_overriden;
61
62	int buffer_size_out_overriden;
63	int period_size_out_overriden;
64	int verbose;
65	} conf = {
66	#ifdef HIGH_LATENCY
67	INIT_FIELD (.size_in_usec_in =) 1,
68	INIT_FIELD (.size_in_usec_out =) 1,
69	#else
70	INIT_FIELD (.size_in_usec_in =) 0,
71	INIT_FIELD (.size_in_usec_out =) 0,
72	#endif
73	INIT_FIELD (.pcm_name_out =) "default",
74	INIT_FIELD (.pcm_name_in =) "default",
75	#ifdef HIGH_LATENCY
76	INIT_FIELD (.buffer_size_in =) 400000,
77	INIT_FIELD (.period_size_in =) 400000 / 4,
78	INIT_FIELD (.buffer_size_out =) 400000,
79	INIT_FIELD (.period_size_out =) 400000 / 4,
80	#else
81	#define DEFAULT_BUFFER_SIZE 1024
82	#define DEFAULT_PERIOD_SIZE 256
83	INIT_FIELD (.buffer_size_in =) DEFAULT_BUFFER_SIZE * 4,
84	INIT_FIELD (.period_size_in =) DEFAULT_PERIOD_SIZE * 4,
85	INIT_FIELD (.buffer_size_out =) DEFAULT_BUFFER_SIZE,
86	INIT_FIELD (.period_size_out =) DEFAULT_PERIOD_SIZE,
87	#endif
88	INIT_FIELD (.threshold =) 0,
89	INIT_FIELD (.buffer_size_in_overriden =) 0,
90	INIT_FIELD (.period_size_in_overriden =) 0,
91	INIT_FIELD (.buffer_size_out_overriden =) 0,
92	INIT_FIELD (.period_size_out_overriden =) 0,
93	INIT_FIELD (.verbose =) 0
94	};
95
96	struct alsa_params_req {
97	int freq;
98	audfmt_e fmt;
99	int nchannels;
100	unsigned long buffer_size;
101	unsigned long period_size;
102	};
103
104	struct alsa_params_obt {
105	int freq;
106	audfmt_e fmt;
107	int nchannels;
108	snd_pcm_uframes_t samples;
109	};
110
111	static void GCC_FMT_ATTR (2, 3) alsa_logerr (int err, const char *fmt, ...)
112	{
113	va_list ap;
114
115	va_start (ap, fmt);
116	AUD_vlog (AUDIO_CAP, fmt, ap);
117	va_end (ap);
118
119	AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
120	}
121
122	static void GCC_FMT_ATTR (3, 4) alsa_logerr2 (
123	int err,
124	const char *typ,
125	const char *fmt,
126	...
127	)
128	{
129	va_list ap;
130
131	AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
132
133	va_start (ap, fmt);
134	AUD_vlog (AUDIO_CAP, fmt, ap);
135	va_end (ap);
136
137	AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
138	}
139
140	static void alsa_anal_close (snd_pcm_t **handlep)
141	{
142	int err = snd_pcm_close (*handlep);
143	if (err) {
144	alsa_logerr (err, "Failed to close PCM handle %p\n",
145	(void ) handlep);
146	}
147	*handlep = NULL;
148	}
149
150	static int alsa_write (SWVoiceOut sw, void buf, int len)
151	{
152	return audio_pcm_sw_write (sw, buf, len);
153	}
154
155	static int aud_to_alsafmt (audfmt_e fmt)
156	{
157	switch (fmt) {
158	case AUD_FMT_S8:
159	return SND_PCM_FORMAT_S8;
160
161	case AUD_FMT_U8:
162	return SND_PCM_FORMAT_U8;
163
164	case AUD_FMT_S16:
165	return SND_PCM_FORMAT_S16_LE;
166
167	case AUD_FMT_U16:
168	return SND_PCM_FORMAT_U16_LE;
169
170	default:
171	dolog ("Internal logic error: Bad audio format %d\n", fmt);
172	#ifdef DEBUG_AUDIO
173	abort ();
174	#endif
175	return SND_PCM_FORMAT_U8;
176	}
177	}
178
179	static int alsa_to_audfmt (int alsafmt, audfmt_e fmt, int endianness)
180	{
181	switch (alsafmt) {
182	case SND_PCM_FORMAT_S8:
183	*endianness = 0;
184	*fmt = AUD_FMT_S8;
185	break;
186
187	case SND_PCM_FORMAT_U8:
188	*endianness = 0;
189	*fmt = AUD_FMT_U8;
190	break;
191
192	case SND_PCM_FORMAT_S16_LE:
193	*endianness = 0;
194	*fmt = AUD_FMT_S16;
195	break;
196
197	case SND_PCM_FORMAT_U16_LE:
198	*endianness = 0;
199	*fmt = AUD_FMT_U16;
200	break;
201
202	case SND_PCM_FORMAT_S16_BE:
203	*endianness = 1;
204	*fmt = AUD_FMT_S16;
205	break;
206
207	case SND_PCM_FORMAT_U16_BE:
208	*endianness = 1;
209	*fmt = AUD_FMT_U16;
210	break;
211
212	default:
213	dolog ("Unrecognized audio format %d\n", alsafmt);
214	return -1;
215	}
216
217	return 0;
218	}
219
220	#if defined DEBUG_MISMATCHES \|\| defined DEBUG
221	static void alsa_dump_info (struct alsa_params_req *req,
222	struct alsa_params_obt *obt)
223	{
224	dolog ("parameter \| requested value \| obtained value\n");
225	dolog ("format \| %10d \| %10d\n", req->fmt, obt->fmt);
226	dolog ("channels \| %10d \| %10d\n",
227	req->nchannels, obt->nchannels);
228	dolog ("frequency \| %10d \| %10d\n", req->freq, obt->freq);
229	dolog ("============================================\n");
230	dolog ("requested: buffer size %d period size %d\n",
231	req->buffer_size, req->period_size);
232	dolog ("obtained: samples %ld\n", obt->samples);
233	}
234	#endif
235
236	static void alsa_set_threshold (snd_pcm_t *handle, snd_pcm_uframes_t threshold)
237	{
238	int err;
239	snd_pcm_sw_params_t *sw_params;
240
241	snd_pcm_sw_params_alloca (&sw_params);
242
243	err = snd_pcm_sw_params_current (handle, sw_params);
244	if (err < 0) {
245	dolog ("Could not fully initialize DAC\n");
246	alsa_logerr (err, "Failed to get current software parameters\n");
247	return;
248	}
249
250	err = snd_pcm_sw_params_set_start_threshold (handle, sw_params, threshold);
251	if (err < 0) {
252	dolog ("Could not fully initialize DAC\n");
253	alsa_logerr (err, "Failed to set software threshold to %ld\n",
254	threshold);
255	return;
256	}
257
258	err = snd_pcm_sw_params (handle, sw_params);
259	if (err < 0) {
260	dolog ("Could not fully initialize DAC\n");
261	alsa_logerr (err, "Failed to set software parameters\n");
262	return;
263	}
264	}
265
266	static int alsa_open (int in, struct alsa_params_req *req,
267	struct alsa_params_obt obt, snd_pcm_t *handlep)
268	{
269	snd_pcm_t *handle;
270	snd_pcm_hw_params_t *hw_params;
271	int err, dir;
272	unsigned int freq, nchannels;
273	const char *pcm_name = in ? conf.pcm_name_in : conf.pcm_name_out;
274	unsigned int period_size, buffer_size;
275	snd_pcm_uframes_t period_size_f, buffer_size_f;
276	snd_pcm_uframes_t obt_buffer_size, obt_period_size;
277	const char *typ = in ? "ADC" : "DAC";
278
279	freq = req->freq;
280	period_size = req->period_size;
281	buffer_size = req->buffer_size;
282	period_size_f = (snd_pcm_uframes_t)period_size;
283	buffer_size_f = (snd_pcm_uframes_t)buffer_size;
284	nchannels = req->nchannels;
285
286	snd_pcm_hw_params_alloca (&hw_params);
287
288	err = snd_pcm_open (
289	&handle,
290	pcm_name,
291	in ? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK,
292	SND_PCM_NONBLOCK
293	);
294	if (err < 0) {
295	#ifndef VBOX
296	alsa_logerr2 (err, typ, "Failed to open `%s':\n", pcm_name);
297	#else
298	LogRel(("ALSA: Failed to open '%s' as %s\n", pcm_name, typ));
299	#endif
300	return -1;
301	}
302
303	err = snd_pcm_hw_params_any (handle, hw_params);
304	if (err < 0) {
305	#ifndef VBOX
306	alsa_logerr2 (err, typ, "Failed to initialize hardware parameters\n");
307	#else
308	LogRel(("ALSA: Failed to initialize hardware parameters\n"));
309	#endif
310	goto err;
311	}
312
313	err = snd_pcm_hw_params_set_access (
314	handle,
315	hw_params,
316	SND_PCM_ACCESS_RW_INTERLEAVED
317	);
318	if (err < 0) {
319	#ifndef VBOX
320	alsa_logerr2 (err, typ, "Failed to set access type\n");
321	#else
322	LogRel(("ALSA: Failed to set access type\n"));
323	#endif
324	goto err;
325	}
326
327	err = snd_pcm_hw_params_set_format (handle, hw_params, req->fmt);
328	if (err < 0) {
329	#ifndef VBOX
330	alsa_logerr2 (err, typ, "Failed to set format %d\n", req->fmt);
331	#else
332	LogRel(("ALSA: Failed to set format %d\n", req->fmt));
333	#endif
334	goto err;
335	}
336
337	err = snd_pcm_hw_params_set_rate_near (handle, hw_params, &freq, 0);
338	if (err < 0) {
339	#ifndef VBOX
340	alsa_logerr2 (err, typ, "Failed to set frequency %d\n", req->freq);
341	#else
342	LogRel(("ALSA: Failed to set frequency %dHz\n", req->freq));
343	#endif
344	goto err;
345	}
346
347	err = snd_pcm_hw_params_set_channels_near (
348	handle,
349	hw_params,
350	&nchannels
351	);
352	if (err < 0) {
353	#ifndef VBOX
354	alsa_logerr2 (err, typ, "Failed to set number of channels %d\n",
355	req->nchannels);
356	#else
357	LogRel(("ALSA: Failed to set number of channels to %d\n", req->nchannels));
358	#endif
359	goto err;
360	}
361
362	if (nchannels != 1 && nchannels != 2) {
363	#ifndef VBOX
364	alsa_logerr2 (err, typ,
365	"Can not handle obtained number of channels %d\n",
366	nchannels);
367	#else
368	LogRel(("ALSA: Cannot handle obtained number of channels (%d)\n", nchannels));
369	#endif
370	goto err;
371	}
372
373	if (!((in && conf.size_in_usec_in) \|\| (!in && conf.size_in_usec_out))) {
374	if (!buffer_size) {
375	buffer_size = DEFAULT_BUFFER_SIZE;
376	period_size= DEFAULT_PERIOD_SIZE;
377	}
378	}
379
380	if (buffer_size) {
381	if ((in && conf.size_in_usec_in) \|\| (!in && conf.size_in_usec_out)) {
382	if (period_size) {
383	err = snd_pcm_hw_params_set_period_time_near (
384	handle,
385	hw_params,
386	&period_size,
387	0
388	);
389	if (err < 0) {
390	#ifndef VBOX
391	alsa_logerr2 (err, typ,
392	"Failed to set period time %d\n",
393	req->period_size);
394	#else
395	LogRel(("ALSA: Failed to set period time %d\n", req->period_size));
396	#endif
397	goto err;
398	}
399	}
400
401	err = snd_pcm_hw_params_set_buffer_time_near (
402	handle,
403	hw_params,
404	&buffer_size,
405	0
406	);
407
408	if (err < 0) {
409	#ifndef VBOX
410	alsa_logerr2 (err, typ,
411	"Failed to set buffer time %d\n",
412	req->buffer_size);
413	#else
414	LogRel(("ALSA: Failed to set buffer time %d\n", req->buffer_size));
415	#endif
416	goto err;
417	}
418	}
419	else {
420	snd_pcm_uframes_t minval;
421
422	if (period_size_f) {
423	minval = period_size_f;
424	dir = 0;
425
426	err = snd_pcm_hw_params_get_period_size_min (
427	hw_params,
428	&minval,
429	&dir
430	);
431	if (err < 0) {
432	#ifndef VBOX
433	alsa_logerr (
434	err,
435	"Could not get minmal period size for %s\n",
436	typ
437	);
438	#else
439	LogRel(("ALSA: Could not get minimal period size for %s\n", typ));
440	#endif
441	}
442	else {
443	dolog("minimal period size %ld\n", minval);
444	if (period_size_f < minval) {
445	if ((in && conf.period_size_in_overriden)
446	\|\| (!in && conf.period_size_out_overriden)) {
447	dolog ("%s period size(%d) is less "
448	"than minmal period size(%ld)\n",
449	typ,
450	period_size_f,
451	minval);
452	}
453	period_size_f = minval;
454	}
455	}
456
457	#ifndef VBOX
458	err = snd_pcm_hw_params_set_period_size (
459	handle,
460	hw_params,
461	period_size_f,
462	0
463	);
464	#else
465	err = snd_pcm_hw_params_set_period_size_near (
466	handle,
467	hw_params,
468	&period_size_f,
469	0
470	);
471	#endif
472	dolog("PERIOD_SIZE %d\n", period_size_f);
473	if (err < 0) {
474	#ifndef VBOX
475	alsa_logerr2 (err, typ, "Failed to set period size %d\n",
476	period_size_f);
477	#else
478	LogRel(("ALSA: Failed to set period size %d (%s)\n",
479	period_size_f, snd_strerror(err)));
480	#endif
481	goto err;
482	}
483	}
484
485	#ifdef VBOX
486	/* Calculate default buffer size here since it might have been changed
487	* in the _near functions */
488	buffer_size_f = 4 * period_size_f;
489	#endif
490
491	minval = buffer_size_f;
492	err = snd_pcm_hw_params_get_buffer_size_min (
493	hw_params,
494	&minval
495	);
496	if (err < 0) {
497	#ifndef VBOX
498	alsa_logerr (err, "Could not get minmal buffer size for %s\n",
499	typ);
500	#else
501	LogRel(("ALSA: Could not get minimal buffer size for %s\n", typ));
502	#endif
503	}
504	else {
505	if (buffer_size_f < minval) {
506	if ((in && conf.buffer_size_in_overriden)
507	\|\| (!in && conf.buffer_size_out_overriden)) {
508	dolog (
509	"%s buffer size(%d) is less "
510	"than minimal buffer size(%ld)\n",
511	typ,
512	buffer_size_f,
513	minval
514	);
515	}
516	buffer_size_f = minval;
517	}
518	}
519
520	err = snd_pcm_hw_params_set_buffer_size_near (
521	handle,
522	hw_params,
523	&buffer_size_f
524	);
525	dolog("BUFFER_SIZE %d\n", buffer_size_f);
526	if (err < 0) {
527	#ifndef VBOX
528	alsa_logerr2 (err, typ, "Failed to set buffer size %d\n",
529	buffer_size_f);
530	#else
531	LogRel(("ALSA: Failed to set buffer size %d (%s)\n",
532	buffer_size_f, snd_strerror(err)));
533	#endif
534	goto err;
535	}
536	}
537	}
538	else {
539	dolog ("warning: Buffer size is not set\n");
540	}
541
542	err = snd_pcm_hw_params (handle, hw_params);
543	if (err < 0) {
544	#ifndef VBOX
545	alsa_logerr2 (err, typ, "Failed to apply audio parameters\n");
546	#else
547	LogRel(("ALSA: Failed to apply audio parameters\n"));
548	#endif
549	goto err;
550	}
551
552	err = snd_pcm_hw_params_get_buffer_size (hw_params, &obt_buffer_size);
553	if (err < 0) {
554	#ifndef VBOX
555	alsa_logerr2 (err, typ, "Failed to get buffer size\n");
556	#else
557	LogRel(("ALSA: Failed to get buffer size\n"));
558	#endif
559	goto err;
560	}
561
562	#ifdef VBOX
563	dir = 0;
564	err = snd_pcm_hw_params_get_period_size (hw_params, &obt_period_size, &dir);
565	if (err < 0)
566	{
567	LogRel(("ALSA: Failed to get period size\n"));
568	goto err;
569	}
570	LogRel(("ALSA: %s frequency %dHz, period size %ld, buffer size %ld\n",
571	typ, req->freq, obt_period_size, obt_buffer_size));
572	#endif
573
574	err = snd_pcm_prepare (handle);
575	if (err < 0) {
576	alsa_logerr2 (err, typ, "Could not prepare handle %p\n",
577	(void *) handle);
578	goto err;
579	}
580
581	if (!in && conf.threshold) {
582	snd_pcm_uframes_t threshold;
583	int bytes_per_sec;
584
585	bytes_per_sec = freq
586	<< (nchannels == 2)
587	<< (req->fmt == AUD_FMT_S16 \|\| req->fmt == AUD_FMT_U16);
588
589	threshold = (conf.threshold * bytes_per_sec) / 1000;
590	alsa_set_threshold (handle, threshold);
591	}
592
593	obt->fmt = req->fmt;
594	obt->nchannels = nchannels;
595	obt->freq = freq;
596	obt->samples = obt_buffer_size;
597	*handlep = handle;
598
599	#if defined DEBUG_MISMATCHES \|\| defined DEBUG
600	if (obt->fmt != req->fmt \|\|
601	obt->nchannels != req->nchannels \|\|
602	obt->freq != req->freq) {
603	dolog ("Audio paramters mismatch for %s\n", typ);
604	alsa_dump_info (req, obt);
605	}
606	#endif
607
608	#ifdef DEBUG
609	alsa_dump_info (req, obt);
610	#endif
611	return 0;
612
613	err:
614	alsa_anal_close (&handle);
615	return -1;
616	}
617
618	static int alsa_recover (snd_pcm_t *handle)
619	{
620	int err = snd_pcm_prepare (handle);
621	if (err < 0) {
622	alsa_logerr (err, "Failed to prepare handle %p\n",
623	(void *) handle);
624	return -1;
625	}
626	return 0;
627	}
628
629	static snd_pcm_sframes_t alsa_get_avail (snd_pcm_t *handle)
630	{
631	snd_pcm_sframes_t avail;
632
633	avail = snd_pcm_avail_update (handle);
634	if (avail < 0) {
635	if (avail == -EPIPE) {
636	if (!alsa_recover (handle)) {
637	avail = snd_pcm_avail_update (handle);
638	}
639	}
640
641	if (avail < 0) {
642	alsa_logerr (avail,
643	"Could not obtain number of available frames\n");
644	return -1;
645	}
646	}
647
648	return avail;
649	}
650
651	static int alsa_run_out (HWVoiceOut *hw)
652	{
653	ALSAVoiceOut alsa = (ALSAVoiceOut ) hw;
654	int rpos, live, decr;
655	int samples;
656	uint8_t *dst;
657	st_sample_t *src;
658	snd_pcm_sframes_t avail;
659
660	live = audio_pcm_hw_get_live_out (hw);
661	if (!live) {
662	return 0;
663	}
664
665	avail = alsa_get_avail (alsa->handle);
666	if (avail < 0) {
667	dolog ("Could not get number of available playback frames\n");
668	return 0;
669	}
670
671	decr = audio_MIN (live, avail);
672	samples = decr;
673	rpos = hw->rpos;
674	while (samples) {
675	int left_till_end_samples = hw->samples - rpos;
676	int len = audio_MIN (samples, left_till_end_samples);
677	snd_pcm_sframes_t written;
678
679	src = hw->mix_buf + rpos;
680	dst = advance (alsa->pcm_buf, rpos << hw->info.shift);
681
682	hw->clip (dst, src, len);
683
684	while (len) {
685	written = snd_pcm_writei (alsa->handle, dst, len);
686
687	if (written <= 0) {
688	switch (written) {
689	case 0:
690	if (conf.verbose) {
691	dolog ("Failed to write %d frames (wrote zero)\n", len);
692	}
693	goto exit;
694
695	case -EPIPE:
696	if (alsa_recover (alsa->handle)) {
697	alsa_logerr (written, "Failed to write %d frames\n",
698	len);
699	goto exit;
700	}
701	if (conf.verbose) {
702	dolog ("Recovering from playback xrun\n");
703	}
704	continue;
705
706	case -EAGAIN:
707	goto exit;
708
709	default:
710	alsa_logerr (written, "Failed to write %d frames to %p\n",
711	len, dst);
712	goto exit;
713	}
714	}
715
716	rpos = (rpos + written) % hw->samples;
717	samples -= written;
718	len -= written;
719	dst = advance (dst, written << hw->info.shift);
720	src += written;
721	}
722	}
723
724	exit:
725	hw->rpos = rpos;
726	return decr;
727	}
728
729	static void alsa_fini_out (HWVoiceOut *hw)
730	{
731	ALSAVoiceOut alsa = (ALSAVoiceOut ) hw;
732
733	ldebug ("alsa_fini\n");
734	alsa_anal_close (&alsa->handle);
735
736	if (alsa->pcm_buf) {
737	qemu_free (alsa->pcm_buf);
738	alsa->pcm_buf = NULL;
739	}
740	}
741
742	static int alsa_init_out (HWVoiceOut hw, audsettings_t as)
743	{
744	ALSAVoiceOut alsa = (ALSAVoiceOut ) hw;
745	struct alsa_params_req req;
746	struct alsa_params_obt obt;
747	audfmt_e effective_fmt;
748	int endianness;
749	int err;
750	snd_pcm_t *handle;
751	audsettings_t obt_as;
752
753	req.fmt = aud_to_alsafmt (as->fmt);
754	req.freq = as->freq;
755	req.nchannels = as->nchannels;
756	req.period_size = conf.period_size_out;
757	req.buffer_size = conf.buffer_size_out;
758
759	if (alsa_open (0, &req, &obt, &handle)) {
760	return -1;
761	}
762
763	err = alsa_to_audfmt (obt.fmt, &effective_fmt, &endianness);
764	if (err) {
765	alsa_anal_close (&handle);
766	return -1;
767	}
768
769	obt_as.freq = obt.freq;
770	obt_as.nchannels = obt.nchannels;
771	obt_as.fmt = effective_fmt;
772	obt_as.endianness = endianness;
773
774	audio_pcm_init_info (&hw->info, &obt_as);
775	hw->samples = obt.samples;
776
777	alsa->pcm_buf = audio_calloc (AUDIO_FUNC, obt.samples, 1 << hw->info.shift);
778	if (!alsa->pcm_buf) {
779	dolog ("Could not allocate DAC buffer (%d samples, each %d bytes)\n",
780	hw->samples, 1 << hw->info.shift);
781	alsa_anal_close (&handle);
782	return -1;
783	}
784
785	alsa->handle = handle;
786	return 0;
787	}
788
789	static int alsa_voice_ctl (snd_pcm_t handle, const char typ, int pause)
790	{
791	int err;
792
793	if (pause) {
794	err = snd_pcm_drop (handle);
795	if (err < 0) {
796	alsa_logerr (err, "Could not stop %s\n", typ);
797	return -1;
798	}
799	}
800	else {
801	err = snd_pcm_prepare (handle);
802	if (err < 0) {
803	alsa_logerr (err, "Could not prepare handle for %s\n", typ);
804	return -1;
805	}
806	}
807
808	return 0;
809	}
810
811	static int alsa_ctl_out (HWVoiceOut *hw, int cmd, ...)
812	{
813	ALSAVoiceOut alsa = (ALSAVoiceOut ) hw;
814
815	switch (cmd) {
816	case VOICE_ENABLE:
817	ldebug ("enabling voice\n");
818	return alsa_voice_ctl (alsa->handle, "playback", 0);
819
820	case VOICE_DISABLE:
821	ldebug ("disabling voice\n");
822	return alsa_voice_ctl (alsa->handle, "playback", 1);
823	}
824
825	return -1;
826	}
827
828	static int alsa_init_in (HWVoiceIn hw, audsettings_t as)
829	{
830	ALSAVoiceIn alsa = (ALSAVoiceIn ) hw;
831	struct alsa_params_req req;
832	struct alsa_params_obt obt;
833	int endianness;
834	int err;
835	audfmt_e effective_fmt;
836	snd_pcm_t *handle;
837	audsettings_t obt_as;
838
839	req.fmt = aud_to_alsafmt (as->fmt);
840	req.freq = as->freq;
841	req.nchannels = as->nchannels;
842	req.period_size = conf.period_size_in;
843	req.buffer_size = conf.buffer_size_in;
844
845	if (alsa_open (1, &req, &obt, &handle)) {
846	return -1;
847	}
848
849	err = alsa_to_audfmt (obt.fmt, &effective_fmt, &endianness);
850	if (err) {
851	alsa_anal_close (&handle);
852	return -1;
853	}
854
855	obt_as.freq = obt.freq;
856	obt_as.nchannels = obt.nchannels;
857	obt_as.fmt = effective_fmt;
858	obt_as.endianness = endianness;
859
860	audio_pcm_init_info (&hw->info, &obt_as);
861	hw->samples = obt.samples;
862
863	alsa->pcm_buf = audio_calloc (AUDIO_FUNC, hw->samples, 1 << hw->info.shift);
864	if (!alsa->pcm_buf) {
865	dolog ("Could not allocate ADC buffer (%d samples, each %d bytes)\n",
866	hw->samples, 1 << hw->info.shift);
867	alsa_anal_close (&handle);
868	return -1;
869	}
870
871	alsa->handle = handle;
872	return 0;
873	}
874
875	static void alsa_fini_in (HWVoiceIn *hw)
876	{
877	ALSAVoiceIn alsa = (ALSAVoiceIn ) hw;
878
879	alsa_anal_close (&alsa->handle);
880
881	if (alsa->pcm_buf) {
882	qemu_free (alsa->pcm_buf);
883	alsa->pcm_buf = NULL;
884	}
885	}
886
887	static int alsa_run_in (HWVoiceIn *hw)
888	{
889	ALSAVoiceIn alsa = (ALSAVoiceIn ) hw;
890	int hwshift = hw->info.shift;
891	int i;
892	int live = audio_pcm_hw_get_live_in (hw);
893	int dead = hw->samples - live;
894	int decr;
895	struct {
896	int add;
897	int len;
898	} bufs[2];
899
900	snd_pcm_sframes_t avail;
901	snd_pcm_uframes_t read_samples = 0;
902
903	bufs[0].add = hw->wpos;
904	bufs[0].len = 0;
905	bufs[1].add = 0;
906	bufs[1].len = 0;
907
908	if (!dead) {
909	return 0;
910	}
911
912	avail = alsa_get_avail (alsa->handle);
913	if (avail < 0) {
914	dolog ("Could not get number of captured frames\n");
915	return 0;
916	}
917
918	if (!avail && (snd_pcm_state (alsa->handle) == SND_PCM_STATE_PREPARED)) {
919	avail = hw->samples;
920	}
921
922	decr = audio_MIN (dead, avail);
923	if (!decr) {
924	return 0;
925	}
926
927	if (hw->wpos + decr > hw->samples) {
928	bufs[0].len = (hw->samples - hw->wpos);
929	bufs[1].len = (decr - (hw->samples - hw->wpos));
930	}
931	else {
932	bufs[0].len = decr;
933	}
934
935	for (i = 0; i < 2; ++i) {
936	void *src;
937	st_sample_t *dst;
938	snd_pcm_sframes_t nread;
939	snd_pcm_uframes_t len;
940
941	len = bufs[i].len;
942
943	src = advance (alsa->pcm_buf, bufs[i].add << hwshift);
944	dst = hw->conv_buf + bufs[i].add;
945
946	while (len) {
947	nread = snd_pcm_readi (alsa->handle, src, len);
948
949	if (nread <= 0) {
950	switch (nread) {
951	case 0:
952	if (conf.verbose) {
953	dolog ("Failed to read %ld frames (read zero)\n", len);
954	}
955	goto exit;
956
957	case -EPIPE:
958	if (alsa_recover (alsa->handle)) {
959	alsa_logerr (nread, "Failed to read %ld frames\n", len);
960	goto exit;
961	}
962	if (conf.verbose) {
963	dolog ("Recovering from capture xrun\n");
964	}
965	continue;
966
967	case -EAGAIN:
968	goto exit;
969
970	default:
971	alsa_logerr (
972	nread,
973	"Failed to read %ld frames from %p\n",
974	len,
975	src
976	);
977	goto exit;
978	}
979	}
980
981	hw->conv (dst, src, nread, &nominal_volume);
982
983	src = advance (src, nread << hwshift);
984	dst += nread;
985
986	read_samples += nread;
987	len -= nread;
988	}
989	}
990
991	exit:
992	hw->wpos = (hw->wpos + read_samples) % hw->samples;
993	return read_samples;
994	}
995
996	static int alsa_read (SWVoiceIn sw, void buf, int size)
997	{
998	return audio_pcm_sw_read (sw, buf, size);
999	}
1000
1001	static int alsa_ctl_in (HWVoiceIn *hw, int cmd, ...)
1002	{
1003	ALSAVoiceIn alsa = (ALSAVoiceIn ) hw;
1004
1005	switch (cmd) {
1006	case VOICE_ENABLE:
1007	ldebug ("enabling voice\n");
1008	return alsa_voice_ctl (alsa->handle, "capture", 0);
1009
1010	case VOICE_DISABLE:
1011	ldebug ("disabling voice\n");
1012	return alsa_voice_ctl (alsa->handle, "capture", 1);
1013	}
1014
1015	return -1;
1016	}
1017
1018	static void *alsa_audio_init (void)
1019	{
1020	return &conf;
1021	}
1022
1023	static void alsa_audio_fini (void *opaque)
1024	{
1025	(void) opaque;
1026	}
1027
1028	static struct audio_option alsa_options[] = {
1029	{"DAC_SIZE_IN_USEC", AUD_OPT_BOOL, &conf.size_in_usec_out,
1030	"DAC period/buffer size in microseconds (otherwise in frames)", NULL, 0},
1031	{"DAC_PERIOD_SIZE", AUD_OPT_INT, &conf.period_size_out,
1032	"DAC period size", &conf.period_size_out_overriden, 0},
1033	{"DAC_BUFFER_SIZE", AUD_OPT_INT, &conf.buffer_size_out,
1034	"DAC buffer size", &conf.buffer_size_out_overriden, 0},
1035
1036	{"ADC_SIZE_IN_USEC", AUD_OPT_BOOL, &conf.size_in_usec_in,
1037	"ADC period/buffer size in microseconds (otherwise in frames)", NULL, 0},
1038	{"ADC_PERIOD_SIZE", AUD_OPT_INT, &conf.period_size_in,
1039	"ADC period size", &conf.period_size_in_overriden, 0},
1040	{"ADC_BUFFER_SIZE", AUD_OPT_INT, &conf.buffer_size_in,
1041	"ADC buffer size", &conf.buffer_size_in_overriden, 0},
1042
1043	{"THRESHOLD", AUD_OPT_INT, &conf.threshold,
1044	"(undocumented)", NULL, 0},
1045
1046	{"DAC_DEV", AUD_OPT_STR, &conf.pcm_name_out,
1047	"DAC device name (for instance dmix)", NULL, 0},
1048
1049	{"ADC_DEV", AUD_OPT_STR, &conf.pcm_name_in,
1050	"ADC device name", NULL, 0},
1051
1052	{"VERBOSE", AUD_OPT_BOOL, &conf.verbose,
1053	"Behave in a more verbose way", NULL, 0},
1054
1055	{NULL, 0, NULL, NULL, NULL, 0}
1056	};
1057
1058	static struct audio_pcm_ops alsa_pcm_ops = {
1059	alsa_init_out,
1060	alsa_fini_out,
1061	alsa_run_out,
1062	alsa_write,
1063	alsa_ctl_out,
1064
1065	alsa_init_in,
1066	alsa_fini_in,
1067	alsa_run_in,
1068	alsa_read,
1069	alsa_ctl_in
1070	};
1071
1072	struct audio_driver alsa_audio_driver = {
1073	INIT_FIELD (name = ) "alsa",
1074	INIT_FIELD (descr = ) "ALSA http://www.alsa-project.org",
1075	INIT_FIELD (options = ) alsa_options,
1076	INIT_FIELD (init = ) alsa_audio_init,
1077	INIT_FIELD (fini = ) alsa_audio_fini,
1078	INIT_FIELD (pcm_ops = ) &alsa_pcm_ops,
1079	INIT_FIELD (can_be_default = ) 1,
1080	INIT_FIELD (max_voices_out = ) INT_MAX,
1081	INIT_FIELD (max_voices_in = ) INT_MAX,
1082	INIT_FIELD (voice_size_out = ) sizeof (ALSAVoiceOut),
1083	INIT_FIELD (voice_size_in = ) sizeof (ALSAVoiceIn)
1084	};

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source: vbox/trunk/src/VBox/Devices/Audio/alsaaudio.c@ 2564

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