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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 "qemu-common.h"
26
#include "audio.h"
27

    
28
#define AUDIO_CAP "alsa"
29
#include "audio_int.h"
30

    
31
typedef struct ALSAVoiceOut {
32
    HWVoiceOut hw;
33
    void *pcm_buf;
34
    snd_pcm_t *handle;
35
} ALSAVoiceOut;
36

    
37
typedef struct ALSAVoiceIn {
38
    HWVoiceIn hw;
39
    snd_pcm_t *handle;
40
    void *pcm_buf;
41
} ALSAVoiceIn;
42

    
43
static struct {
44
    int size_in_usec_in;
45
    int size_in_usec_out;
46
    const char *pcm_name_in;
47
    const char *pcm_name_out;
48
    unsigned int buffer_size_in;
49
    unsigned int period_size_in;
50
    unsigned int buffer_size_out;
51
    unsigned int period_size_out;
52
    unsigned int threshold;
53

    
54
    int buffer_size_in_overridden;
55
    int period_size_in_overridden;
56

    
57
    int buffer_size_out_overridden;
58
    int period_size_out_overridden;
59
    int verbose;
60
} conf = {
61
    .pcm_name_out = "default",
62
    .pcm_name_in = "default",
63
};
64

    
65
struct alsa_params_req {
66
    int freq;
67
    snd_pcm_format_t fmt;
68
    int nchannels;
69
    int size_in_usec;
70
    unsigned int buffer_size;
71
    unsigned int period_size;
72
};
73

    
74
struct alsa_params_obt {
75
    int freq;
76
    audfmt_e fmt;
77
    int endianness;
78
    int nchannels;
79
    snd_pcm_uframes_t samples;
80
};
81

    
82
static void GCC_FMT_ATTR (2, 3) alsa_logerr (int err, const char *fmt, ...)
83
{
84
    va_list ap;
85

    
86
    va_start (ap, fmt);
87
    AUD_vlog (AUDIO_CAP, fmt, ap);
88
    va_end (ap);
89

    
90
    AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
91
}
92

    
93
static void GCC_FMT_ATTR (3, 4) alsa_logerr2 (
94
    int err,
95
    const char *typ,
96
    const char *fmt,
97
    ...
98
    )
99
{
100
    va_list ap;
101

    
102
    AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
103

    
104
    va_start (ap, fmt);
105
    AUD_vlog (AUDIO_CAP, fmt, ap);
106
    va_end (ap);
107

    
108
    AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
109
}
110

    
111
static void alsa_anal_close (snd_pcm_t **handlep)
112
{
113
    int err = snd_pcm_close (*handlep);
114
    if (err) {
115
        alsa_logerr (err, "Failed to close PCM handle %p\n", *handlep);
116
    }
117
    *handlep = NULL;
118
}
119

    
120
static int alsa_write (SWVoiceOut *sw, void *buf, int len)
121
{
122
    return audio_pcm_sw_write (sw, buf, len);
123
}
124

    
125
static snd_pcm_format_t aud_to_alsafmt (audfmt_e fmt)
126
{
127
    switch (fmt) {
128
    case AUD_FMT_S8:
129
        return SND_PCM_FORMAT_S8;
130

    
131
    case AUD_FMT_U8:
132
        return SND_PCM_FORMAT_U8;
133

    
134
    case AUD_FMT_S16:
135
        return SND_PCM_FORMAT_S16_LE;
136

    
137
    case AUD_FMT_U16:
138
        return SND_PCM_FORMAT_U16_LE;
139

    
140
    case AUD_FMT_S32:
141
        return SND_PCM_FORMAT_S32_LE;
142

    
143
    case AUD_FMT_U32:
144
        return SND_PCM_FORMAT_U32_LE;
145

    
146
    default:
147
        dolog ("Internal logic error: Bad audio format %d\n", fmt);
148
#ifdef DEBUG_AUDIO
149
        abort ();
150
#endif
151
        return SND_PCM_FORMAT_U8;
152
    }
153
}
154

    
155
static int alsa_to_audfmt (snd_pcm_format_t alsafmt, audfmt_e *fmt,
156
                           int *endianness)
157
{
158
    switch (alsafmt) {
159
    case SND_PCM_FORMAT_S8:
160
        *endianness = 0;
161
        *fmt = AUD_FMT_S8;
162
        break;
163

    
164
    case SND_PCM_FORMAT_U8:
165
        *endianness = 0;
166
        *fmt = AUD_FMT_U8;
167
        break;
168

    
169
    case SND_PCM_FORMAT_S16_LE:
170
        *endianness = 0;
171
        *fmt = AUD_FMT_S16;
172
        break;
173

    
174
    case SND_PCM_FORMAT_U16_LE:
175
        *endianness = 0;
176
        *fmt = AUD_FMT_U16;
177
        break;
178

    
179
    case SND_PCM_FORMAT_S16_BE:
180
        *endianness = 1;
181
        *fmt = AUD_FMT_S16;
182
        break;
183

    
184
    case SND_PCM_FORMAT_U16_BE:
185
        *endianness = 1;
186
        *fmt = AUD_FMT_U16;
187
        break;
188

    
189
    case SND_PCM_FORMAT_S32_LE:
190
        *endianness = 0;
191
        *fmt = AUD_FMT_S32;
192
        break;
193

    
194
    case SND_PCM_FORMAT_U32_LE:
195
        *endianness = 0;
196
        *fmt = AUD_FMT_U32;
197
        break;
198

    
199
    case SND_PCM_FORMAT_S32_BE:
200
        *endianness = 1;
201
        *fmt = AUD_FMT_S32;
202
        break;
203

    
204
    case SND_PCM_FORMAT_U32_BE:
205
        *endianness = 1;
206
        *fmt = AUD_FMT_U32;
207
        break;
208

    
209
    default:
210
        dolog ("Unrecognized audio format %d\n", alsafmt);
211
        return -1;
212
    }
213

    
214
    return 0;
215
}
216

    
217
static void alsa_dump_info (struct alsa_params_req *req,
218
                            struct alsa_params_obt *obt)
219
{
220
    dolog ("parameter | requested value | obtained value\n");
221
    dolog ("format    |      %10d |     %10d\n", req->fmt, obt->fmt);
222
    dolog ("channels  |      %10d |     %10d\n",
223
           req->nchannels, obt->nchannels);
224
    dolog ("frequency |      %10d |     %10d\n", req->freq, obt->freq);
225
    dolog ("============================================\n");
226
    dolog ("requested: buffer size %d period size %d\n",
227
           req->buffer_size, req->period_size);
228
    dolog ("obtained: samples %ld\n", obt->samples);
229
}
230

    
231
static void alsa_set_threshold (snd_pcm_t *handle, snd_pcm_uframes_t threshold)
232
{
233
    int err;
234
    snd_pcm_sw_params_t *sw_params;
235

    
236
    snd_pcm_sw_params_alloca (&sw_params);
237

    
238
    err = snd_pcm_sw_params_current (handle, sw_params);
239
    if (err < 0) {
240
        dolog ("Could not fully initialize DAC\n");
241
        alsa_logerr (err, "Failed to get current software parameters\n");
242
        return;
243
    }
244

    
245
    err = snd_pcm_sw_params_set_start_threshold (handle, sw_params, threshold);
246
    if (err < 0) {
247
        dolog ("Could not fully initialize DAC\n");
248
        alsa_logerr (err, "Failed to set software threshold to %ld\n",
249
                     threshold);
250
        return;
251
    }
252

    
253
    err = snd_pcm_sw_params (handle, sw_params);
254
    if (err < 0) {
255
        dolog ("Could not fully initialize DAC\n");
256
        alsa_logerr (err, "Failed to set software parameters\n");
257
        return;
258
    }
259
}
260

    
261
static int alsa_open (int in, struct alsa_params_req *req,
262
                      struct alsa_params_obt *obt, snd_pcm_t **handlep)
263
{
264
    snd_pcm_t *handle;
265
    snd_pcm_hw_params_t *hw_params;
266
    int err;
267
    int size_in_usec;
268
    unsigned int freq, nchannels;
269
    const char *pcm_name = in ? conf.pcm_name_in : conf.pcm_name_out;
270
    snd_pcm_uframes_t obt_buffer_size;
271
    const char *typ = in ? "ADC" : "DAC";
272
    snd_pcm_format_t obtfmt;
273

    
274
    freq = req->freq;
275
    nchannels = req->nchannels;
276
    size_in_usec = req->size_in_usec;
277

    
278
    snd_pcm_hw_params_alloca (&hw_params);
279

    
280
    err = snd_pcm_open (
281
        &handle,
282
        pcm_name,
283
        in ? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK,
284
        SND_PCM_NONBLOCK
285
        );
286
    if (err < 0) {
287
        alsa_logerr2 (err, typ, "Failed to open `%s':\n", pcm_name);
288
        return -1;
289
    }
290

    
291
    err = snd_pcm_hw_params_any (handle, hw_params);
292
    if (err < 0) {
293
        alsa_logerr2 (err, typ, "Failed to initialize hardware parameters\n");
294
        goto err;
295
    }
296

    
297
    err = snd_pcm_hw_params_set_access (
298
        handle,
299
        hw_params,
300
        SND_PCM_ACCESS_RW_INTERLEAVED
301
        );
302
    if (err < 0) {
303
        alsa_logerr2 (err, typ, "Failed to set access type\n");
304
        goto err;
305
    }
306

    
307
    err = snd_pcm_hw_params_set_format (handle, hw_params, req->fmt);
308
    if (err < 0 && conf.verbose) {
309
        alsa_logerr2 (err, typ, "Failed to set format %d\n", req->fmt);
310
    }
311

    
312
    err = snd_pcm_hw_params_set_rate_near (handle, hw_params, &freq, 0);
313
    if (err < 0) {
314
        alsa_logerr2 (err, typ, "Failed to set frequency %d\n", req->freq);
315
        goto err;
316
    }
317

    
318
    err = snd_pcm_hw_params_set_channels_near (
319
        handle,
320
        hw_params,
321
        &nchannels
322
        );
323
    if (err < 0) {
324
        alsa_logerr2 (err, typ, "Failed to set number of channels %d\n",
325
                      req->nchannels);
326
        goto err;
327
    }
328

    
329
    if (nchannels != 1 && nchannels != 2) {
330
        alsa_logerr2 (err, typ,
331
                      "Can not handle obtained number of channels %d\n",
332
                      nchannels);
333
        goto err;
334
    }
335

    
336
    if (req->buffer_size) {
337
        if (size_in_usec) {
338
            int dir = 0;
339
            unsigned int btime = req->buffer_size;
340

    
341
            err = snd_pcm_hw_params_set_buffer_time_near (
342
                handle,
343
                hw_params,
344
                &btime,
345
                &dir
346
                );
347
        }
348
        else {
349
            snd_pcm_uframes_t bsize = req->buffer_size;
350

    
351
            err = snd_pcm_hw_params_set_buffer_size_near (
352
                handle,
353
                hw_params,
354
                &bsize
355
                );
356
        }
357
        if (err < 0) {
358
            alsa_logerr2 (err, typ, "Failed to set buffer %s to %d\n",
359
                          size_in_usec ? "time" : "size", req->buffer_size);
360
            goto err;
361
        }
362
    }
363

    
364
    if (req->period_size) {
365
        if (size_in_usec) {
366
            int dir = 0;
367
            unsigned int ptime = req->period_size;
368

    
369
            err = snd_pcm_hw_params_set_period_time_near (
370
                handle,
371
                hw_params,
372
                &ptime,
373
                &dir
374
                );
375
        }
376
        else {
377
            snd_pcm_uframes_t psize = req->period_size;
378

    
379
            err = snd_pcm_hw_params_set_buffer_size_near (
380
                handle,
381
                hw_params,
382
                &psize
383
                );
384
        }
385

    
386
        if (err < 0) {
387
            alsa_logerr2 (err, typ, "Failed to set period %s to %d\n",
388
                          size_in_usec ? "time" : "size", req->period_size);
389
            goto err;
390
        }
391
    }
392

    
393
    err = snd_pcm_hw_params (handle, hw_params);
394
    if (err < 0) {
395
        alsa_logerr2 (err, typ, "Failed to apply audio parameters\n");
396
        goto err;
397
    }
398

    
399
    err = snd_pcm_hw_params_get_buffer_size (hw_params, &obt_buffer_size);
400
    if (err < 0) {
401
        alsa_logerr2 (err, typ, "Failed to get buffer size\n");
402
        goto err;
403
    }
404

    
405
    err = snd_pcm_hw_params_get_format (hw_params, &obtfmt);
406
    if (err < 0) {
407
        alsa_logerr2 (err, typ, "Failed to get format\n");
408
        goto err;
409
    }
410

    
411
    if (alsa_to_audfmt (obtfmt, &obt->fmt, &obt->endianness)) {
412
        dolog ("Invalid format was returned %d\n", obtfmt);
413
        goto err;
414
    }
415

    
416
    err = snd_pcm_prepare (handle);
417
    if (err < 0) {
418
        alsa_logerr2 (err, typ, "Could not prepare handle %p\n", handle);
419
        goto err;
420
    }
421

    
422
    if (!in && conf.threshold) {
423
        snd_pcm_uframes_t threshold;
424
        int bytes_per_sec;
425

    
426
        bytes_per_sec = freq << (nchannels == 2);
427

    
428
        switch (obt->fmt) {
429
        case AUD_FMT_S8:
430
        case AUD_FMT_U8:
431
            break;
432

    
433
        case AUD_FMT_S16:
434
        case AUD_FMT_U16:
435
            bytes_per_sec <<= 1;
436
            break;
437

    
438
        case AUD_FMT_S32:
439
        case AUD_FMT_U32:
440
            bytes_per_sec <<= 2;
441
            break;
442
        }
443

    
444
        threshold = (conf.threshold * bytes_per_sec) / 1000;
445
        alsa_set_threshold (handle, threshold);
446
    }
447

    
448
    obt->nchannels = nchannels;
449
    obt->freq = freq;
450
    obt->samples = obt_buffer_size;
451

    
452
    *handlep = handle;
453

    
454
    if (conf.verbose &&
455
        (obt->fmt != req->fmt ||
456
         obt->nchannels != req->nchannels ||
457
         obt->freq != req->freq)) {
458
        dolog ("Audio paramters for %s\n", typ);
459
        alsa_dump_info (req, obt);
460
    }
461

    
462
#ifdef DEBUG
463
    alsa_dump_info (req, obt);
464
#endif
465
    return 0;
466

    
467
 err:
468
    alsa_anal_close (&handle);
469
    return -1;
470
}
471

    
472
static int alsa_recover (snd_pcm_t *handle)
473
{
474
    int err = snd_pcm_prepare (handle);
475
    if (err < 0) {
476
        alsa_logerr (err, "Failed to prepare handle %p\n", handle);
477
        return -1;
478
    }
479
    return 0;
480
}
481

    
482
static snd_pcm_sframes_t alsa_get_avail (snd_pcm_t *handle)
483
{
484
    snd_pcm_sframes_t avail;
485

    
486
    avail = snd_pcm_avail_update (handle);
487
    if (avail < 0) {
488
        if (avail == -EPIPE) {
489
            if (!alsa_recover (handle)) {
490
                avail = snd_pcm_avail_update (handle);
491
            }
492
        }
493

    
494
        if (avail < 0) {
495
            alsa_logerr (avail,
496
                         "Could not obtain number of available frames\n");
497
            return -1;
498
        }
499
    }
500

    
501
    return avail;
502
}
503

    
504
static int alsa_run_out (HWVoiceOut *hw)
505
{
506
    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
507
    int rpos, live, decr;
508
    int samples;
509
    uint8_t *dst;
510
    st_sample_t *src;
511
    snd_pcm_sframes_t avail;
512

    
513
    live = audio_pcm_hw_get_live_out (hw);
514
    if (!live) {
515
        return 0;
516
    }
517

    
518
    avail = alsa_get_avail (alsa->handle);
519
    if (avail < 0) {
520
        dolog ("Could not get number of available playback frames\n");
521
        return 0;
522
    }
523

    
524
    decr = audio_MIN (live, avail);
525
    samples = decr;
526
    rpos = hw->rpos;
527
    while (samples) {
528
        int left_till_end_samples = hw->samples - rpos;
529
        int len = audio_MIN (samples, left_till_end_samples);
530
        snd_pcm_sframes_t written;
531

    
532
        src = hw->mix_buf + rpos;
533
        dst = advance (alsa->pcm_buf, rpos << hw->info.shift);
534

    
535
        hw->clip (dst, src, len);
536

    
537
        while (len) {
538
            written = snd_pcm_writei (alsa->handle, dst, len);
539

    
540
            if (written <= 0) {
541
                switch (written) {
542
                case 0:
543
                    if (conf.verbose) {
544
                        dolog ("Failed to write %d frames (wrote zero)\n", len);
545
                    }
546
                    goto exit;
547

    
548
                case -EPIPE:
549
                    if (alsa_recover (alsa->handle)) {
550
                        alsa_logerr (written, "Failed to write %d frames\n",
551
                                     len);
552
                        goto exit;
553
                    }
554
                    if (conf.verbose) {
555
                        dolog ("Recovering from playback xrun\n");
556
                    }
557
                    continue;
558

    
559
                case -EAGAIN:
560
                    goto exit;
561

    
562
                default:
563
                    alsa_logerr (written, "Failed to write %d frames to %p\n",
564
                                 len, dst);
565
                    goto exit;
566
                }
567
            }
568

    
569
            rpos = (rpos + written) % hw->samples;
570
            samples -= written;
571
            len -= written;
572
            dst = advance (dst, written << hw->info.shift);
573
            src += written;
574
        }
575
    }
576

    
577
 exit:
578
    hw->rpos = rpos;
579
    return decr;
580
}
581

    
582
static void alsa_fini_out (HWVoiceOut *hw)
583
{
584
    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
585

    
586
    ldebug ("alsa_fini\n");
587
    alsa_anal_close (&alsa->handle);
588

    
589
    if (alsa->pcm_buf) {
590
        qemu_free (alsa->pcm_buf);
591
        alsa->pcm_buf = NULL;
592
    }
593
}
594

    
595
static int alsa_init_out (HWVoiceOut *hw, audsettings_t *as)
596
{
597
    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
598
    struct alsa_params_req req;
599
    struct alsa_params_obt obt;
600
    snd_pcm_t *handle;
601
    audsettings_t obt_as;
602

    
603
    req.fmt = aud_to_alsafmt (as->fmt);
604
    req.freq = as->freq;
605
    req.nchannels = as->nchannels;
606
    req.period_size = conf.period_size_out;
607
    req.buffer_size = conf.buffer_size_out;
608
    req.size_in_usec = conf.size_in_usec_in;
609

    
610
    if (alsa_open (0, &req, &obt, &handle)) {
611
        return -1;
612
    }
613

    
614
    obt_as.freq = obt.freq;
615
    obt_as.nchannels = obt.nchannels;
616
    obt_as.fmt = obt.fmt;
617
    obt_as.endianness = obt.endianness;
618

    
619
    audio_pcm_init_info (&hw->info, &obt_as);
620
    hw->samples = obt.samples;
621

    
622
    alsa->pcm_buf = audio_calloc (AUDIO_FUNC, obt.samples, 1 << hw->info.shift);
623
    if (!alsa->pcm_buf) {
624
        dolog ("Could not allocate DAC buffer (%d samples, each %d bytes)\n",
625
               hw->samples, 1 << hw->info.shift);
626
        alsa_anal_close (&handle);
627
        return -1;
628
    }
629

    
630
    alsa->handle = handle;
631
    return 0;
632
}
633

    
634
static int alsa_voice_ctl (snd_pcm_t *handle, const char *typ, int pause)
635
{
636
    int err;
637

    
638
    if (pause) {
639
        err = snd_pcm_drop (handle);
640
        if (err < 0) {
641
            alsa_logerr (err, "Could not stop %s\n", typ);
642
            return -1;
643
        }
644
    }
645
    else {
646
        err = snd_pcm_prepare (handle);
647
        if (err < 0) {
648
            alsa_logerr (err, "Could not prepare handle for %s\n", typ);
649
            return -1;
650
        }
651
    }
652

    
653
    return 0;
654
}
655

    
656
static int alsa_ctl_out (HWVoiceOut *hw, int cmd, ...)
657
{
658
    ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
659

    
660
    switch (cmd) {
661
    case VOICE_ENABLE:
662
        ldebug ("enabling voice\n");
663
        return alsa_voice_ctl (alsa->handle, "playback", 0);
664

    
665
    case VOICE_DISABLE:
666
        ldebug ("disabling voice\n");
667
        return alsa_voice_ctl (alsa->handle, "playback", 1);
668
    }
669

    
670
    return -1;
671
}
672

    
673
static int alsa_init_in (HWVoiceIn *hw, audsettings_t *as)
674
{
675
    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
676
    struct alsa_params_req req;
677
    struct alsa_params_obt obt;
678
    snd_pcm_t *handle;
679
    audsettings_t obt_as;
680

    
681
    req.fmt = aud_to_alsafmt (as->fmt);
682
    req.freq = as->freq;
683
    req.nchannels = as->nchannels;
684
    req.period_size = conf.period_size_in;
685
    req.buffer_size = conf.buffer_size_in;
686
    req.size_in_usec = conf.size_in_usec_in;
687

    
688
    if (alsa_open (1, &req, &obt, &handle)) {
689
        return -1;
690
    }
691

    
692
    obt_as.freq = obt.freq;
693
    obt_as.nchannels = obt.nchannels;
694
    obt_as.fmt = obt.fmt;
695
    obt_as.endianness = obt.endianness;
696

    
697
    audio_pcm_init_info (&hw->info, &obt_as);
698
    hw->samples = obt.samples;
699

    
700
    alsa->pcm_buf = audio_calloc (AUDIO_FUNC, hw->samples, 1 << hw->info.shift);
701
    if (!alsa->pcm_buf) {
702
        dolog ("Could not allocate ADC buffer (%d samples, each %d bytes)\n",
703
               hw->samples, 1 << hw->info.shift);
704
        alsa_anal_close (&handle);
705
        return -1;
706
    }
707

    
708
    alsa->handle = handle;
709
    return 0;
710
}
711

    
712
static void alsa_fini_in (HWVoiceIn *hw)
713
{
714
    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
715

    
716
    alsa_anal_close (&alsa->handle);
717

    
718
    if (alsa->pcm_buf) {
719
        qemu_free (alsa->pcm_buf);
720
        alsa->pcm_buf = NULL;
721
    }
722
}
723

    
724
static int alsa_run_in (HWVoiceIn *hw)
725
{
726
    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
727
    int hwshift = hw->info.shift;
728
    int i;
729
    int live = audio_pcm_hw_get_live_in (hw);
730
    int dead = hw->samples - live;
731
    int decr;
732
    struct {
733
        int add;
734
        int len;
735
    } bufs[2] = {
736
        { hw->wpos, 0 },
737
        { 0, 0 }
738
    };
739
    snd_pcm_sframes_t avail;
740
    snd_pcm_uframes_t read_samples = 0;
741

    
742
    if (!dead) {
743
        return 0;
744
    }
745

    
746
    avail = alsa_get_avail (alsa->handle);
747
    if (avail < 0) {
748
        dolog ("Could not get number of captured frames\n");
749
        return 0;
750
    }
751

    
752
    if (!avail && (snd_pcm_state (alsa->handle) == SND_PCM_STATE_PREPARED)) {
753
        avail = hw->samples;
754
    }
755

    
756
    decr = audio_MIN (dead, avail);
757
    if (!decr) {
758
        return 0;
759
    }
760

    
761
    if (hw->wpos + decr > hw->samples) {
762
        bufs[0].len = (hw->samples - hw->wpos);
763
        bufs[1].len = (decr - (hw->samples - hw->wpos));
764
    }
765
    else {
766
        bufs[0].len = decr;
767
    }
768

    
769
    for (i = 0; i < 2; ++i) {
770
        void *src;
771
        st_sample_t *dst;
772
        snd_pcm_sframes_t nread;
773
        snd_pcm_uframes_t len;
774

    
775
        len = bufs[i].len;
776

    
777
        src = advance (alsa->pcm_buf, bufs[i].add << hwshift);
778
        dst = hw->conv_buf + bufs[i].add;
779

    
780
        while (len) {
781
            nread = snd_pcm_readi (alsa->handle, src, len);
782

    
783
            if (nread <= 0) {
784
                switch (nread) {
785
                case 0:
786
                    if (conf.verbose) {
787
                        dolog ("Failed to read %ld frames (read zero)\n", len);
788
                    }
789
                    goto exit;
790

    
791
                case -EPIPE:
792
                    if (alsa_recover (alsa->handle)) {
793
                        alsa_logerr (nread, "Failed to read %ld frames\n", len);
794
                        goto exit;
795
                    }
796
                    if (conf.verbose) {
797
                        dolog ("Recovering from capture xrun\n");
798
                    }
799
                    continue;
800

    
801
                case -EAGAIN:
802
                    goto exit;
803

    
804
                default:
805
                    alsa_logerr (
806
                        nread,
807
                        "Failed to read %ld frames from %p\n",
808
                        len,
809
                        src
810
                        );
811
                    goto exit;
812
                }
813
            }
814

    
815
            hw->conv (dst, src, nread, &nominal_volume);
816

    
817
            src = advance (src, nread << hwshift);
818
            dst += nread;
819

    
820
            read_samples += nread;
821
            len -= nread;
822
        }
823
    }
824

    
825
 exit:
826
    hw->wpos = (hw->wpos + read_samples) % hw->samples;
827
    return read_samples;
828
}
829

    
830
static int alsa_read (SWVoiceIn *sw, void *buf, int size)
831
{
832
    return audio_pcm_sw_read (sw, buf, size);
833
}
834

    
835
static int alsa_ctl_in (HWVoiceIn *hw, int cmd, ...)
836
{
837
    ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
838

    
839
    switch (cmd) {
840
    case VOICE_ENABLE:
841
        ldebug ("enabling voice\n");
842
        return alsa_voice_ctl (alsa->handle, "capture", 0);
843

    
844
    case VOICE_DISABLE:
845
        ldebug ("disabling voice\n");
846
        return alsa_voice_ctl (alsa->handle, "capture", 1);
847
    }
848

    
849
    return -1;
850
}
851

    
852
static void *alsa_audio_init (void)
853
{
854
    return &conf;
855
}
856

    
857
static void alsa_audio_fini (void *opaque)
858
{
859
    (void) opaque;
860
}
861

    
862
static struct audio_option alsa_options[] = {
863
    {"DAC_SIZE_IN_USEC", AUD_OPT_BOOL, &conf.size_in_usec_out,
864
     "DAC period/buffer size in microseconds (otherwise in frames)", NULL, 0},
865
    {"DAC_PERIOD_SIZE", AUD_OPT_INT, &conf.period_size_out,
866
     "DAC period size (0 to go with system default)",
867
     &conf.period_size_out_overridden, 0},
868
    {"DAC_BUFFER_SIZE", AUD_OPT_INT, &conf.buffer_size_out,
869
     "DAC buffer size (0 to go with system default)",
870
     &conf.buffer_size_out_overridden, 0},
871

    
872
    {"ADC_SIZE_IN_USEC", AUD_OPT_BOOL, &conf.size_in_usec_in,
873
     "ADC period/buffer size in microseconds (otherwise in frames)", NULL, 0},
874
    {"ADC_PERIOD_SIZE", AUD_OPT_INT, &conf.period_size_in,
875
     "ADC period size (0 to go with system default)",
876
     &conf.period_size_in_overridden, 0},
877
    {"ADC_BUFFER_SIZE", AUD_OPT_INT, &conf.buffer_size_in,
878
     "ADC buffer size (0 to go with system default)",
879
     &conf.buffer_size_in_overridden, 0},
880

    
881
    {"THRESHOLD", AUD_OPT_INT, &conf.threshold,
882
     "(undocumented)", NULL, 0},
883

    
884
    {"DAC_DEV", AUD_OPT_STR, &conf.pcm_name_out,
885
     "DAC device name (for instance dmix)", NULL, 0},
886

    
887
    {"ADC_DEV", AUD_OPT_STR, &conf.pcm_name_in,
888
     "ADC device name", NULL, 0},
889

    
890
    {"VERBOSE", AUD_OPT_BOOL, &conf.verbose,
891
     "Behave in a more verbose way", NULL, 0},
892

    
893
    {NULL, 0, NULL, NULL, NULL, 0}
894
};
895

    
896
static struct audio_pcm_ops alsa_pcm_ops = {
897
    alsa_init_out,
898
    alsa_fini_out,
899
    alsa_run_out,
900
    alsa_write,
901
    alsa_ctl_out,
902

    
903
    alsa_init_in,
904
    alsa_fini_in,
905
    alsa_run_in,
906
    alsa_read,
907
    alsa_ctl_in
908
};
909

    
910
struct audio_driver alsa_audio_driver = {
911
    INIT_FIELD (name           = ) "alsa",
912
    INIT_FIELD (descr          = ) "ALSA http://www.alsa-project.org",
913
    INIT_FIELD (options        = ) alsa_options,
914
    INIT_FIELD (init           = ) alsa_audio_init,
915
    INIT_FIELD (fini           = ) alsa_audio_fini,
916
    INIT_FIELD (pcm_ops        = ) &alsa_pcm_ops,
917
    INIT_FIELD (can_be_default = ) 1,
918
    INIT_FIELD (max_voices_out = ) INT_MAX,
919
    INIT_FIELD (max_voices_in  = ) INT_MAX,
920
    INIT_FIELD (voice_size_out = ) sizeof (ALSAVoiceOut),
921
    INIT_FIELD (voice_size_in  = ) sizeof (ALSAVoiceIn)
922
};