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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
#include "vl.h"
26

    
27
#define AUDIO_CAP "alsa"
28
#include "audio_int.h"
29

    
30
typedef struct ALSAVoiceOut {
31
    HWVoiceOut hw;
32
    void *pcm_buf;
33
    snd_pcm_t *handle;
34
} ALSAVoiceOut;
35

    
36
typedef struct ALSAVoiceIn {
37
    HWVoiceIn hw;
38
    snd_pcm_t *handle;
39
    void *pcm_buf;
40
} ALSAVoiceIn;
41

    
42
static struct {
43
    int size_in_usec_in;
44
    int size_in_usec_out;
45
    const char *pcm_name_in;
46
    const char *pcm_name_out;
47
    unsigned int buffer_size_in;
48
    unsigned int period_size_in;
49
    unsigned int buffer_size_out;
50
    unsigned int period_size_out;
51
    unsigned int threshold;
52

    
53
    int buffer_size_in_overriden;
54
    int period_size_in_overriden;
55

    
56
    int buffer_size_out_overriden;
57
    int period_size_out_overriden;
58
    int verbose;
59
} conf = {
60
#ifdef HIGH_LATENCY
61
    .size_in_usec_in = 1,
62
    .size_in_usec_out = 1,
63
#endif
64
    .pcm_name_out = "hw:0,0",
65
    .pcm_name_in = "hw:0,0",
66
#ifdef HIGH_LATENCY
67
    .buffer_size_in = 400000,
68
    .period_size_in = 400000 / 4,
69
    .buffer_size_out = 400000,
70
    .period_size_out = 400000 / 4,
71
#else
72
#define DEFAULT_BUFFER_SIZE 1024
73
#define DEFAULT_PERIOD_SIZE 256
74
    .buffer_size_in = DEFAULT_BUFFER_SIZE * 4,
75
    .period_size_in = DEFAULT_PERIOD_SIZE * 4,
76
    .buffer_size_out = DEFAULT_BUFFER_SIZE,
77
    .period_size_out = DEFAULT_PERIOD_SIZE,
78
    .buffer_size_in_overriden = 0,
79
    .buffer_size_out_overriden = 0,
80
    .period_size_in_overriden = 0,
81
    .period_size_out_overriden = 0,
82
#endif
83
    .threshold = 0,
84
    .verbose = 0
85
};
86

    
87
struct alsa_params_req {
88
    int freq;
89
    audfmt_e fmt;
90
    int nchannels;
91
    unsigned int buffer_size;
92
    unsigned int period_size;
93
};
94

    
95
struct alsa_params_obt {
96
    int freq;
97
    audfmt_e fmt;
98
    int nchannels;
99
    snd_pcm_uframes_t samples;
100
};
101

    
102
static void GCC_FMT_ATTR (2, 3) alsa_logerr (int err, const char *fmt, ...)
103
{
104
    va_list ap;
105

    
106
    va_start (ap, fmt);
107
    AUD_vlog (AUDIO_CAP, fmt, ap);
108
    va_end (ap);
109

    
110
    AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
111
}
112

    
113
static void GCC_FMT_ATTR (3, 4) alsa_logerr2 (
114
    int err,
115
    const char *typ,
116
    const char *fmt,
117
    ...
118
    )
119
{
120
    va_list ap;
121

    
122
    AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
123

    
124
    va_start (ap, fmt);
125
    AUD_vlog (AUDIO_CAP, fmt, ap);
126
    va_end (ap);
127

    
128
    AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
129
}
130

    
131
static void alsa_anal_close (snd_pcm_t **handlep)
132
{
133
    int err = snd_pcm_close (*handlep);
134
    if (err) {
135
        alsa_logerr (err, "Failed to close PCM handle %p\n", *handlep);
136
    }
137
    *handlep = NULL;
138
}
139

    
140
static int alsa_write (SWVoiceOut *sw, void *buf, int len)
141
{
142
    return audio_pcm_sw_write (sw, buf, len);
143
}
144

    
145
static int aud_to_alsafmt (audfmt_e fmt)
146
{
147
    switch (fmt) {
148
    case AUD_FMT_S8:
149
        return SND_PCM_FORMAT_S8;
150

    
151
    case AUD_FMT_U8:
152
        return SND_PCM_FORMAT_U8;
153

    
154
    case AUD_FMT_S16:
155
        return SND_PCM_FORMAT_S16_LE;
156

    
157
    case AUD_FMT_U16:
158
        return SND_PCM_FORMAT_U16_LE;
159

    
160
    default:
161
        dolog ("Internal logic error: Bad audio format %d\n", fmt);
162
#ifdef DEBUG_AUDIO
163
        abort ();
164
#endif
165
        return SND_PCM_FORMAT_U8;
166
    }
167
}
168

    
169
static int alsa_to_audfmt (int alsafmt, audfmt_e *fmt, int *endianness)
170
{
171
    switch (alsafmt) {
172
    case SND_PCM_FORMAT_S8:
173
        *endianness = 0;
174
        *fmt = AUD_FMT_S8;
175
        break;
176

    
177
    case SND_PCM_FORMAT_U8:
178
        *endianness = 0;
179
        *fmt = AUD_FMT_U8;
180
        break;
181

    
182
    case SND_PCM_FORMAT_S16_LE:
183
        *endianness = 0;
184
        *fmt = AUD_FMT_S16;
185
        break;
186

    
187
    case SND_PCM_FORMAT_U16_LE:
188
        *endianness = 0;
189
        *fmt = AUD_FMT_U16;
190
        break;
191

    
192
    case SND_PCM_FORMAT_S16_BE:
193
        *endianness = 1;
194
        *fmt = AUD_FMT_S16;
195
        break;
196

    
197
    case SND_PCM_FORMAT_U16_BE:
198
        *endianness = 1;
199
        *fmt = AUD_FMT_U16;
200
        break;
201

    
202
    default:
203
        dolog ("Unrecognized audio format %d\n", alsafmt);
204
        return -1;
205
    }
206

    
207
    return 0;
208
}
209

    
210
#if defined DEBUG_MISMATCHES || defined DEBUG
211
static void alsa_dump_info (struct alsa_params_req *req,
212
                            struct alsa_params_obt *obt)
213
{
214
    dolog ("parameter | requested value | obtained value\n");
215
    dolog ("format    |      %10d |     %10d\n", req->fmt, obt->fmt);
216
    dolog ("channels  |      %10d |     %10d\n",
217
           req->nchannels, obt->nchannels);
218
    dolog ("frequency |      %10d |     %10d\n", req->freq, obt->freq);
219
    dolog ("============================================\n");
220
    dolog ("requested: buffer size %d period size %d\n",
221
           req->buffer_size, req->period_size);
222
    dolog ("obtained: samples %ld\n", obt->samples);
223
}
224
#endif
225

    
226
static void alsa_set_threshold (snd_pcm_t *handle, snd_pcm_uframes_t threshold)
227
{
228
    int err;
229
    snd_pcm_sw_params_t *sw_params;
230

    
231
    snd_pcm_sw_params_alloca (&sw_params);
232

    
233
    err = snd_pcm_sw_params_current (handle, sw_params);
234
    if (err < 0) {
235
        dolog ("Could not fully initialize DAC\n");
236
        alsa_logerr (err, "Failed to get current software parameters\n");
237
        return;
238
    }
239

    
240
    err = snd_pcm_sw_params_set_start_threshold (handle, sw_params, threshold);
241
    if (err < 0) {
242
        dolog ("Could not fully initialize DAC\n");
243
        alsa_logerr (err, "Failed to set software threshold to %ld\n",
244
                     threshold);
245
        return;
246
    }
247

    
248
    err = snd_pcm_sw_params (handle, sw_params);
249
    if (err < 0) {
250
        dolog ("Could not fully initialize DAC\n");
251
        alsa_logerr (err, "Failed to set software parameters\n");
252
        return;
253
    }
254
}
255

    
256
static int alsa_open (int in, struct alsa_params_req *req,
257
                      struct alsa_params_obt *obt, snd_pcm_t **handlep)
258
{
259
    snd_pcm_t *handle;
260
    snd_pcm_hw_params_t *hw_params;
261
    int err, freq, nchannels;
262
    const char *pcm_name = in ? conf.pcm_name_in : conf.pcm_name_out;
263
    unsigned int period_size, buffer_size;
264
    snd_pcm_uframes_t obt_buffer_size;
265
    const char *typ = in ? "ADC" : "DAC";
266

    
267
    freq = req->freq;
268
    period_size = req->period_size;
269
    buffer_size = req->buffer_size;
270
    nchannels = req->nchannels;
271

    
272
    snd_pcm_hw_params_alloca (&hw_params);
273

    
274
    err = snd_pcm_open (
275
        &handle,
276
        pcm_name,
277
        in ? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK,
278
        SND_PCM_NONBLOCK
279
        );
280
    if (err < 0) {
281
        alsa_logerr2 (err, typ, "Failed to open `%s':\n", pcm_name);
282
        return -1;
283
    }
284

    
285
    err = snd_pcm_hw_params_any (handle, hw_params);
286
    if (err < 0) {
287
        alsa_logerr2 (err, typ, "Failed to initialize hardware parameters\n");
288
        goto err;
289
    }
290

    
291
    err = snd_pcm_hw_params_set_access (
292
        handle,
293
        hw_params,
294
        SND_PCM_ACCESS_RW_INTERLEAVED
295
        );
296
    if (err < 0) {
297
        alsa_logerr2 (err, typ, "Failed to set access type\n");
298
        goto err;
299
    }
300

    
301
    err = snd_pcm_hw_params_set_format (handle, hw_params, req->fmt);
302
    if (err < 0) {
303
        alsa_logerr2 (err, typ, "Failed to set format %d\n", req->fmt);
304
        goto err;
305
    }
306

    
307
    err = snd_pcm_hw_params_set_rate_near (handle, hw_params, &freq, 0);
308
    if (err < 0) {
309
        alsa_logerr2 (err, typ, "Failed to set frequency %d\n", req->freq);
310
        goto err;
311
    }
312

    
313
    err = snd_pcm_hw_params_set_channels_near (
314
        handle,
315
        hw_params,
316
        &nchannels
317
        );
318
    if (err < 0) {
319
        alsa_logerr2 (err, typ, "Failed to set number of channels %d\n",
320
                      req->nchannels);
321
        goto err;
322
    }
323

    
324
    if (nchannels != 1 && nchannels != 2) {
325
        alsa_logerr2 (err, typ,
326
                      "Can not handle obtained number of channels %d\n",
327
                      nchannels);
328
        goto err;
329
    }
330

    
331
    if (!((in && conf.size_in_usec_in) || (!in && conf.size_in_usec_out))) {
332
        if (!buffer_size) {
333
            buffer_size = DEFAULT_BUFFER_SIZE;
334
            period_size= DEFAULT_PERIOD_SIZE;
335
        }
336
    }
337

    
338
    if (buffer_size) {
339
        if ((in && conf.size_in_usec_in) || (!in && conf.size_in_usec_out)) {
340
            if (period_size) {
341
                err = snd_pcm_hw_params_set_period_time_near (
342
                    handle,
343
                    hw_params,
344
                    &period_size,
345
                    0
346
                    );
347
                if (err < 0) {
348
                    alsa_logerr2 (err, typ,
349
                                  "Failed to set period time %d\n",
350
                                  req->period_size);
351
                    goto err;
352
                }
353
            }
354

    
355
            err = snd_pcm_hw_params_set_buffer_time_near (
356
                handle,
357
                hw_params,
358
                &buffer_size,
359
                0
360
                );
361

    
362
            if (err < 0) {
363
                alsa_logerr2 (err, typ,
364
                              "Failed to set buffer time %d\n",
365
                              req->buffer_size);
366
                goto err;
367
            }
368
        }
369
        else {
370
            int dir;
371
            snd_pcm_uframes_t minval;
372

    
373
            if (period_size) {
374
                minval = period_size;
375
                dir = 0;
376

    
377
                err = snd_pcm_hw_params_get_period_size_min (
378
                    hw_params,
379
                    &minval,
380
                    &dir
381
                    );
382
                if (err < 0) {
383
                    alsa_logerr (
384
                        err,
385
                        "Could not get minmal period size for %s\n",
386
                        typ
387
                        );
388
                }
389
                else {
390
                    if (period_size < minval) {
391
                        if ((in && conf.period_size_in_overriden)
392
                            || (!in && conf.period_size_out_overriden)) {
393
                            dolog ("%s period size(%d) is less "
394
                                   "than minmal period size(%ld)\n",
395
                                   typ,
396
                                   period_size,
397
                                   minval);
398
                        }
399
                        period_size = minval;
400
                    }
401
                }
402

    
403
                err = snd_pcm_hw_params_set_period_size (
404
                    handle,
405
                    hw_params,
406
                    period_size,
407
                    0
408
                    );
409
                if (err < 0) {
410
                    alsa_logerr2 (err, typ, "Failed to set period size %d\n",
411
                                  req->period_size);
412
                    goto err;
413
                }
414
            }
415

    
416
            minval = buffer_size;
417
            err = snd_pcm_hw_params_get_buffer_size_min (
418
                hw_params,
419
                &minval
420
                );
421
            if (err < 0) {
422
                alsa_logerr (err, "Could not get minmal buffer size for %s\n",
423
                             typ);
424
            }
425
            else {
426
                if (buffer_size < minval) {
427
                    if ((in && conf.buffer_size_in_overriden)
428
                        || (!in && conf.buffer_size_out_overriden)) {
429
                        dolog (
430
                            "%s buffer size(%d) is less "
431
                            "than minimal buffer size(%ld)\n",
432
                            typ,
433
                            buffer_size,
434
                            minval
435
                            );
436
                    }
437
                    buffer_size = minval;
438
                }
439
            }
440

    
441
            err = snd_pcm_hw_params_set_buffer_size (
442
                handle,
443
                hw_params,
444
                buffer_size
445
                );
446
            if (err < 0) {
447
                alsa_logerr2 (err, typ, "Failed to set buffer size %d\n",
448
                              req->buffer_size);
449
                goto err;
450
            }
451
        }
452
    }
453
    else {
454
        dolog ("warning: Buffer size is not set\n");
455
    }
456

    
457
    err = snd_pcm_hw_params (handle, hw_params);
458
    if (err < 0) {
459
        alsa_logerr2 (err, typ, "Failed to apply audio parameters\n");
460
        goto err;
461
    }
462

    
463
    err = snd_pcm_hw_params_get_buffer_size (hw_params, &obt_buffer_size);
464
    if (err < 0) {
465
        alsa_logerr2 (err, typ, "Failed to get buffer size\n");
466
        goto err;
467
    }
468

    
469
    err = snd_pcm_prepare (handle);
470
    if (err < 0) {
471
        alsa_logerr2 (err, typ, "Could not prepare handle %p\n", handle);
472
        goto err;
473
    }
474

    
475
    if (!in && conf.threshold) {
476
        snd_pcm_uframes_t threshold;
477
        int bytes_per_sec;
478

    
479
        bytes_per_sec = freq
480
            << (nchannels == 2)
481
            << (req->fmt == AUD_FMT_S16 || req->fmt == AUD_FMT_U16);
482

    
483
        threshold = (conf.threshold * bytes_per_sec) / 1000;
484
        alsa_set_threshold (handle, threshold);
485
    }
486

    
487
    obt->fmt = req->fmt;
488
    obt->nchannels = nchannels;
489
    obt->freq = freq;
490
    obt->samples = obt_buffer_size;
491
    *handlep = handle;
492

    
493
#if defined DEBUG_MISMATCHES || defined DEBUG
494
    if (obt->fmt != req->fmt ||
495
        obt->nchannels != req->nchannels ||
496
        obt->freq != req->freq) {
497
        dolog ("Audio paramters mismatch for %s\n", typ);
498
        alsa_dump_info (req, obt);
499
    }
500
#endif
501

    
502
#ifdef DEBUG
503
    alsa_dump_info (req, obt);
504
#endif
505
    return 0;
506

    
507
 err:
508
    alsa_anal_close (&handle);
509
    return -1;
510
}
511

    
512
static int alsa_recover (snd_pcm_t *handle)
513
{
514
    int err = snd_pcm_prepare (handle);
515
    if (err < 0) {
516
        alsa_logerr (err, "Failed to prepare handle %p\n", handle);
517
        return -1;
518
    }
519
    return 0;
520
}
521

    
522
static snd_pcm_sframes_t alsa_get_avail (snd_pcm_t *handle)
523
{
524
    snd_pcm_sframes_t avail;
525

    
526
    avail = snd_pcm_avail_update (handle);
527
    if (avail < 0) {
528
        if (avail == -EPIPE) {
529
            if (!alsa_recover (handle)) {
530
                avail = snd_pcm_avail_update (handle);
531
            }
532
        }
533

    
534
        if (avail < 0) {
535
            alsa_logerr (avail,
536
                         "Could not obtain number of available frames\n");
537
            return -1;
538
        }
539
    }
540

    
541
    return avail;
542
}
543

    
544
static int alsa_run_out (HWVoiceOut *hw)
545
{
546
    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
547
    int rpos, live, decr;
548
    int samples;
549
    uint8_t *dst;
550
    st_sample_t *src;
551
    snd_pcm_sframes_t avail;
552

    
553
    live = audio_pcm_hw_get_live_out (hw);
554
    if (!live) {
555
        return 0;
556
    }
557

    
558
    avail = alsa_get_avail (alsa->handle);
559
    if (avail < 0) {
560
        dolog ("Could not get number of available playback frames\n");
561
        return 0;
562
    }
563

    
564
    decr = audio_MIN (live, avail);
565
    samples = decr;
566
    rpos = hw->rpos;
567
    while (samples) {
568
        int left_till_end_samples = hw->samples - rpos;
569
        int len = audio_MIN (samples, left_till_end_samples);
570
        snd_pcm_sframes_t written;
571

    
572
        src = hw->mix_buf + rpos;
573
        dst = advance (alsa->pcm_buf, rpos << hw->info.shift);
574

    
575
        hw->clip (dst, src, len);
576

    
577
        while (len) {
578
            written = snd_pcm_writei (alsa->handle, dst, len);
579

    
580
            if (written <= 0) {
581
                switch (written) {
582
                case 0:
583
                    if (conf.verbose) {
584
                        dolog ("Failed to write %d frames (wrote zero)\n", len);
585
                    }
586
                    goto exit;
587

    
588
                case -EPIPE:
589
                    if (alsa_recover (alsa->handle)) {
590
                        alsa_logerr (written, "Failed to write %d frames\n",
591
                                     len);
592
                        goto exit;
593
                    }
594
                    if (conf.verbose) {
595
                        dolog ("Recovering from playback xrun\n");
596
                    }
597
                    continue;
598

    
599
                case -EAGAIN:
600
                    goto exit;
601

    
602
                default:
603
                    alsa_logerr (written, "Failed to write %d frames to %p\n",
604
                                 len, dst);
605
                    goto exit;
606
                }
607
            }
608

    
609
            mixeng_clear (src, written);
610
            rpos = (rpos + written) % hw->samples;
611
            samples -= written;
612
            len -= written;
613
            dst = advance (dst, written << hw->info.shift);
614
            src += written;
615
        }
616
    }
617

    
618
 exit:
619
    hw->rpos = rpos;
620
    return decr;
621
}
622

    
623
static void alsa_fini_out (HWVoiceOut *hw)
624
{
625
    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
626

    
627
    ldebug ("alsa_fini\n");
628
    alsa_anal_close (&alsa->handle);
629

    
630
    if (alsa->pcm_buf) {
631
        qemu_free (alsa->pcm_buf);
632
        alsa->pcm_buf = NULL;
633
    }
634
}
635

    
636
static int alsa_init_out (HWVoiceOut *hw, audsettings_t *as)
637
{
638
    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
639
    struct alsa_params_req req;
640
    struct alsa_params_obt obt;
641
    audfmt_e effective_fmt;
642
    int endianness;
643
    int err;
644
    snd_pcm_t *handle;
645
    audsettings_t obt_as;
646

    
647
    req.fmt = aud_to_alsafmt (as->fmt);
648
    req.freq = as->freq;
649
    req.nchannels = as->nchannels;
650
    req.period_size = conf.period_size_out;
651
    req.buffer_size = conf.buffer_size_out;
652

    
653
    if (alsa_open (0, &req, &obt, &handle)) {
654
        return -1;
655
    }
656

    
657
    err = alsa_to_audfmt (obt.fmt, &effective_fmt, &endianness);
658
    if (err) {
659
        alsa_anal_close (&handle);
660
        return -1;
661
    }
662

    
663
    obt_as.freq = obt.freq;
664
    obt_as.nchannels = obt.nchannels;
665
    obt_as.fmt = effective_fmt;
666

    
667
    audio_pcm_init_info (
668
        &hw->info,
669
        &obt_as,
670
        audio_need_to_swap_endian (endianness)
671
        );
672
    hw->samples = obt.samples;
673

    
674
    alsa->pcm_buf = audio_calloc (AUDIO_FUNC, obt.samples, 1 << hw->info.shift);
675
    if (!alsa->pcm_buf) {
676
        dolog ("Could not allocate DAC buffer (%d samples, each %d bytes)\n",
677
               hw->samples, 1 << hw->info.shift);
678
        alsa_anal_close (&handle);
679
        return -1;
680
    }
681

    
682
    alsa->handle = handle;
683
    return 0;
684
}
685

    
686
static int alsa_voice_ctl (snd_pcm_t *handle, const char *typ, int pause)
687
{
688
    int err;
689

    
690
    if (pause) {
691
        err = snd_pcm_drop (handle);
692
        if (err < 0) {
693
            alsa_logerr (err, "Could not stop %s\n", typ);
694
            return -1;
695
        }
696
    }
697
    else {
698
        err = snd_pcm_prepare (handle);
699
        if (err < 0) {
700
            alsa_logerr (err, "Could not prepare handle for %s\n", typ);
701
            return -1;
702
        }
703
    }
704

    
705
    return 0;
706
}
707

    
708
static int alsa_ctl_out (HWVoiceOut *hw, int cmd, ...)
709
{
710
    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
711

    
712
    switch (cmd) {
713
    case VOICE_ENABLE:
714
        ldebug ("enabling voice\n");
715
        return alsa_voice_ctl (alsa->handle, "playback", 0);
716

    
717
    case VOICE_DISABLE:
718
        ldebug ("disabling voice\n");
719
        return alsa_voice_ctl (alsa->handle, "playback", 1);
720
    }
721

    
722
    return -1;
723
}
724

    
725
static int alsa_init_in (HWVoiceIn *hw, audsettings_t *as)
726
{
727
    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
728
    struct alsa_params_req req;
729
    struct alsa_params_obt obt;
730
    int endianness;
731
    int err;
732
    audfmt_e effective_fmt;
733
    snd_pcm_t *handle;
734
    audsettings_t obt_as;
735

    
736
    req.fmt = aud_to_alsafmt (as->fmt);
737
    req.freq = as->freq;
738
    req.nchannels = as->nchannels;
739
    req.period_size = conf.period_size_in;
740
    req.buffer_size = conf.buffer_size_in;
741

    
742
    if (alsa_open (1, &req, &obt, &handle)) {
743
        return -1;
744
    }
745

    
746
    err = alsa_to_audfmt (obt.fmt, &effective_fmt, &endianness);
747
    if (err) {
748
        alsa_anal_close (&handle);
749
        return -1;
750
    }
751

    
752
    obt_as.freq = obt.freq;
753
    obt_as.nchannels = obt.nchannels;
754
    obt_as.fmt = effective_fmt;
755

    
756
    audio_pcm_init_info (
757
        &hw->info,
758
        &obt_as,
759
        audio_need_to_swap_endian (endianness)
760
        );
761
    hw->samples = obt.samples;
762

    
763
    alsa->pcm_buf = audio_calloc (AUDIO_FUNC, hw->samples, 1 << hw->info.shift);
764
    if (!alsa->pcm_buf) {
765
        dolog ("Could not allocate ADC buffer (%d samples, each %d bytes)\n",
766
               hw->samples, 1 << hw->info.shift);
767
        alsa_anal_close (&handle);
768
        return -1;
769
    }
770

    
771
    alsa->handle = handle;
772
    return 0;
773
}
774

    
775
static void alsa_fini_in (HWVoiceIn *hw)
776
{
777
    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
778

    
779
    alsa_anal_close (&alsa->handle);
780

    
781
    if (alsa->pcm_buf) {
782
        qemu_free (alsa->pcm_buf);
783
        alsa->pcm_buf = NULL;
784
    }
785
}
786

    
787
static int alsa_run_in (HWVoiceIn *hw)
788
{
789
    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
790
    int hwshift = hw->info.shift;
791
    int i;
792
    int live = audio_pcm_hw_get_live_in (hw);
793
    int dead = hw->samples - live;
794
    int decr;
795
    struct {
796
        int add;
797
        int len;
798
    } bufs[2] = {
799
        { hw->wpos, 0 },
800
        { 0, 0 }
801
    };
802
    snd_pcm_sframes_t avail;
803
    snd_pcm_uframes_t read_samples = 0;
804

    
805
    if (!dead) {
806
        return 0;
807
    }
808

    
809
    avail = alsa_get_avail (alsa->handle);
810
    if (avail < 0) {
811
        dolog ("Could not get number of captured frames\n");
812
        return 0;
813
    }
814

    
815
    if (!avail && (snd_pcm_state (alsa->handle) == SND_PCM_STATE_PREPARED)) {
816
        avail = hw->samples;
817
    }
818

    
819
    decr = audio_MIN (dead, avail);
820
    if (!decr) {
821
        return 0;
822
    }
823

    
824
    if (hw->wpos + decr > hw->samples) {
825
        bufs[0].len = (hw->samples - hw->wpos);
826
        bufs[1].len = (decr - (hw->samples - hw->wpos));
827
    }
828
    else {
829
        bufs[0].len = decr;
830
    }
831

    
832
    for (i = 0; i < 2; ++i) {
833
        void *src;
834
        st_sample_t *dst;
835
        snd_pcm_sframes_t nread;
836
        snd_pcm_uframes_t len;
837

    
838
        len = bufs[i].len;
839

    
840
        src = advance (alsa->pcm_buf, bufs[i].add << hwshift);
841
        dst = hw->conv_buf + bufs[i].add;
842

    
843
        while (len) {
844
            nread = snd_pcm_readi (alsa->handle, src, len);
845

    
846
            if (nread <= 0) {
847
                switch (nread) {
848
                case 0:
849
                    if (conf.verbose) {
850
                        dolog ("Failed to read %ld frames (read zero)\n", len);
851
                    }
852
                    goto exit;
853

    
854
                case -EPIPE:
855
                    if (alsa_recover (alsa->handle)) {
856
                        alsa_logerr (nread, "Failed to read %ld frames\n", len);
857
                        goto exit;
858
                    }
859
                    if (conf.verbose) {
860
                        dolog ("Recovering from capture xrun\n");
861
                    }
862
                    continue;
863

    
864
                case -EAGAIN:
865
                    goto exit;
866

    
867
                default:
868
                    alsa_logerr (
869
                        nread,
870
                        "Failed to read %ld frames from %p\n",
871
                        len,
872
                        src
873
                        );
874
                    goto exit;
875
                }
876
            }
877

    
878
            hw->conv (dst, src, nread, &nominal_volume);
879

    
880
            src = advance (src, nread << hwshift);
881
            dst += nread;
882

    
883
            read_samples += nread;
884
            len -= nread;
885
        }
886
    }
887

    
888
 exit:
889
    hw->wpos = (hw->wpos + read_samples) % hw->samples;
890
    return read_samples;
891
}
892

    
893
static int alsa_read (SWVoiceIn *sw, void *buf, int size)
894
{
895
    return audio_pcm_sw_read (sw, buf, size);
896
}
897

    
898
static int alsa_ctl_in (HWVoiceIn *hw, int cmd, ...)
899
{
900
    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
901

    
902
    switch (cmd) {
903
    case VOICE_ENABLE:
904
        ldebug ("enabling voice\n");
905
        return alsa_voice_ctl (alsa->handle, "capture", 0);
906

    
907
    case VOICE_DISABLE:
908
        ldebug ("disabling voice\n");
909
        return alsa_voice_ctl (alsa->handle, "capture", 1);
910
    }
911

    
912
    return -1;
913
}
914

    
915
static void *alsa_audio_init (void)
916
{
917
    return &conf;
918
}
919

    
920
static void alsa_audio_fini (void *opaque)
921
{
922
    (void) opaque;
923
}
924

    
925
static struct audio_option alsa_options[] = {
926
    {"DAC_SIZE_IN_USEC", AUD_OPT_BOOL, &conf.size_in_usec_out,
927
     "DAC period/buffer size in microseconds (otherwise in frames)", NULL, 0},
928
    {"DAC_PERIOD_SIZE", AUD_OPT_INT, &conf.period_size_out,
929
     "DAC period size", &conf.period_size_out_overriden, 0},
930
    {"DAC_BUFFER_SIZE", AUD_OPT_INT, &conf.buffer_size_out,
931
     "DAC buffer size", &conf.buffer_size_out_overriden, 0},
932

    
933
    {"ADC_SIZE_IN_USEC", AUD_OPT_BOOL, &conf.size_in_usec_in,
934
     "ADC period/buffer size in microseconds (otherwise in frames)", NULL, 0},
935
    {"ADC_PERIOD_SIZE", AUD_OPT_INT, &conf.period_size_in,
936
     "ADC period size", &conf.period_size_in_overriden, 0},
937
    {"ADC_BUFFER_SIZE", AUD_OPT_INT, &conf.buffer_size_in,
938
     "ADC buffer size", &conf.buffer_size_in_overriden, 0},
939

    
940
    {"THRESHOLD", AUD_OPT_INT, &conf.threshold,
941
     "(undocumented)", NULL, 0},
942

    
943
    {"DAC_DEV", AUD_OPT_STR, &conf.pcm_name_out,
944
     "DAC device name (for instance dmix)", NULL, 0},
945

    
946
    {"ADC_DEV", AUD_OPT_STR, &conf.pcm_name_in,
947
     "ADC device name", NULL, 0},
948

    
949
    {"VERBOSE", AUD_OPT_BOOL, &conf.verbose,
950
     "Behave in a more verbose way", NULL, 0},
951

    
952
    {NULL, 0, NULL, NULL, NULL, 0}
953
};
954

    
955
static struct audio_pcm_ops alsa_pcm_ops = {
956
    alsa_init_out,
957
    alsa_fini_out,
958
    alsa_run_out,
959
    alsa_write,
960
    alsa_ctl_out,
961

    
962
    alsa_init_in,
963
    alsa_fini_in,
964
    alsa_run_in,
965
    alsa_read,
966
    alsa_ctl_in
967
};
968

    
969
struct audio_driver alsa_audio_driver = {
970
    INIT_FIELD (name           = ) "alsa",
971
    INIT_FIELD (descr          = ) "ALSA http://www.alsa-project.org",
972
    INIT_FIELD (options        = ) alsa_options,
973
    INIT_FIELD (init           = ) alsa_audio_init,
974
    INIT_FIELD (fini           = ) alsa_audio_fini,
975
    INIT_FIELD (pcm_ops        = ) &alsa_pcm_ops,
976
    INIT_FIELD (can_be_default = ) 1,
977
    INIT_FIELD (max_voices_out = ) INT_MAX,
978
    INIT_FIELD (max_voices_in  = ) INT_MAX,
979
    INIT_FIELD (voice_size_out = ) sizeof (ALSAVoiceOut),
980
    INIT_FIELD (voice_size_in  = ) sizeof (ALSAVoiceIn)
981
};