2 * QEMU ALSA audio driver
4 * Copyright (c) 2005 Vassili Karpov (malc)
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:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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
25 #include "qemu/osdep.h"
26 #include <alsa/asoundlib.h>
27 #include "qemu/main-loop.h"
28 #include "qemu/module.h"
32 #pragma GCC diagnostic ignored "-Waddress"
34 #define AUDIO_CAP "alsa"
35 #include "audio_int.h"
45 typedef struct ALSAVoiceOut
{
48 struct pollhlp pollhlp
;
52 typedef struct ALSAVoiceIn
{
55 struct pollhlp pollhlp
;
59 struct alsa_params_req
{
65 struct alsa_params_obt
{
70 snd_pcm_uframes_t samples
;
73 static void GCC_FMT_ATTR (2, 3) alsa_logerr (int err
, const char *fmt
, ...)
78 AUD_vlog (AUDIO_CAP
, fmt
, ap
);
81 AUD_log (AUDIO_CAP
, "Reason: %s\n", snd_strerror (err
));
84 static void GCC_FMT_ATTR (3, 4) alsa_logerr2 (
93 AUD_log (AUDIO_CAP
, "Could not initialize %s\n", typ
);
96 AUD_vlog (AUDIO_CAP
, fmt
, ap
);
99 AUD_log (AUDIO_CAP
, "Reason: %s\n", snd_strerror (err
));
102 static void alsa_fini_poll (struct pollhlp
*hlp
)
105 struct pollfd
*pfds
= hlp
->pfds
;
108 for (i
= 0; i
< hlp
->count
; ++i
) {
109 qemu_set_fd_handler (pfds
[i
].fd
, NULL
, NULL
, NULL
);
118 static void alsa_anal_close1 (snd_pcm_t
**handlep
)
120 int err
= snd_pcm_close (*handlep
);
122 alsa_logerr (err
, "Failed to close PCM handle %p\n", *handlep
);
127 static void alsa_anal_close (snd_pcm_t
**handlep
, struct pollhlp
*hlp
)
129 alsa_fini_poll (hlp
);
130 alsa_anal_close1 (handlep
);
133 static int alsa_recover (snd_pcm_t
*handle
)
135 int err
= snd_pcm_prepare (handle
);
137 alsa_logerr (err
, "Failed to prepare handle %p\n", handle
);
143 static int alsa_resume (snd_pcm_t
*handle
)
145 int err
= snd_pcm_resume (handle
);
147 alsa_logerr (err
, "Failed to resume handle %p\n", handle
);
153 static void alsa_poll_handler (void *opaque
)
156 snd_pcm_state_t state
;
157 struct pollhlp
*hlp
= opaque
;
158 unsigned short revents
;
160 count
= poll (hlp
->pfds
, hlp
->count
, 0);
162 dolog ("alsa_poll_handler: poll %s\n", strerror (errno
));
170 /* XXX: ALSA example uses initial count, not the one returned by
172 err
= snd_pcm_poll_descriptors_revents (hlp
->handle
, hlp
->pfds
,
173 hlp
->count
, &revents
);
175 alsa_logerr (err
, "snd_pcm_poll_descriptors_revents");
179 if (!(revents
& hlp
->mask
)) {
180 trace_alsa_revents(revents
);
184 state
= snd_pcm_state (hlp
->handle
);
186 case SND_PCM_STATE_SETUP
:
187 alsa_recover (hlp
->handle
);
190 case SND_PCM_STATE_XRUN
:
191 alsa_recover (hlp
->handle
);
194 case SND_PCM_STATE_SUSPENDED
:
195 alsa_resume (hlp
->handle
);
198 case SND_PCM_STATE_PREPARED
:
199 audio_run(hlp
->s
, "alsa run (prepared)");
202 case SND_PCM_STATE_RUNNING
:
203 audio_run(hlp
->s
, "alsa run (running)");
207 dolog ("Unexpected state %d\n", state
);
211 static int alsa_poll_helper (snd_pcm_t
*handle
, struct pollhlp
*hlp
, int mask
)
216 count
= snd_pcm_poll_descriptors_count (handle
);
218 dolog ("Could not initialize poll mode\n"
219 "Invalid number of poll descriptors %d\n", count
);
223 pfds
= audio_calloc ("alsa_poll_helper", count
, sizeof (*pfds
));
225 dolog ("Could not initialize poll mode\n");
229 err
= snd_pcm_poll_descriptors (handle
, pfds
, count
);
231 alsa_logerr (err
, "Could not initialize poll mode\n"
232 "Could not obtain poll descriptors\n");
237 for (i
= 0; i
< count
; ++i
) {
238 if (pfds
[i
].events
& POLLIN
) {
239 qemu_set_fd_handler (pfds
[i
].fd
, alsa_poll_handler
, NULL
, hlp
);
241 if (pfds
[i
].events
& POLLOUT
) {
242 trace_alsa_pollout(i
, pfds
[i
].fd
);
243 qemu_set_fd_handler (pfds
[i
].fd
, NULL
, alsa_poll_handler
, hlp
);
245 trace_alsa_set_handler(pfds
[i
].events
, i
, pfds
[i
].fd
, err
);
250 hlp
->handle
= handle
;
255 static int alsa_poll_out (HWVoiceOut
*hw
)
257 ALSAVoiceOut
*alsa
= (ALSAVoiceOut
*) hw
;
259 return alsa_poll_helper (alsa
->handle
, &alsa
->pollhlp
, POLLOUT
);
262 static int alsa_poll_in (HWVoiceIn
*hw
)
264 ALSAVoiceIn
*alsa
= (ALSAVoiceIn
*) hw
;
266 return alsa_poll_helper (alsa
->handle
, &alsa
->pollhlp
, POLLIN
);
269 static snd_pcm_format_t
aud_to_alsafmt (AudioFormat fmt
, int endianness
)
272 case AUDIO_FORMAT_S8
:
273 return SND_PCM_FORMAT_S8
;
275 case AUDIO_FORMAT_U8
:
276 return SND_PCM_FORMAT_U8
;
278 case AUDIO_FORMAT_S16
:
280 return SND_PCM_FORMAT_S16_BE
;
283 return SND_PCM_FORMAT_S16_LE
;
286 case AUDIO_FORMAT_U16
:
288 return SND_PCM_FORMAT_U16_BE
;
291 return SND_PCM_FORMAT_U16_LE
;
294 case AUDIO_FORMAT_S32
:
296 return SND_PCM_FORMAT_S32_BE
;
299 return SND_PCM_FORMAT_S32_LE
;
302 case AUDIO_FORMAT_U32
:
304 return SND_PCM_FORMAT_U32_BE
;
307 return SND_PCM_FORMAT_U32_LE
;
311 dolog ("Internal logic error: Bad audio format %d\n", fmt
);
315 return SND_PCM_FORMAT_U8
;
319 static int alsa_to_audfmt (snd_pcm_format_t alsafmt
, AudioFormat
*fmt
,
323 case SND_PCM_FORMAT_S8
:
325 *fmt
= AUDIO_FORMAT_S8
;
328 case SND_PCM_FORMAT_U8
:
330 *fmt
= AUDIO_FORMAT_U8
;
333 case SND_PCM_FORMAT_S16_LE
:
335 *fmt
= AUDIO_FORMAT_S16
;
338 case SND_PCM_FORMAT_U16_LE
:
340 *fmt
= AUDIO_FORMAT_U16
;
343 case SND_PCM_FORMAT_S16_BE
:
345 *fmt
= AUDIO_FORMAT_S16
;
348 case SND_PCM_FORMAT_U16_BE
:
350 *fmt
= AUDIO_FORMAT_U16
;
353 case SND_PCM_FORMAT_S32_LE
:
355 *fmt
= AUDIO_FORMAT_S32
;
358 case SND_PCM_FORMAT_U32_LE
:
360 *fmt
= AUDIO_FORMAT_U32
;
363 case SND_PCM_FORMAT_S32_BE
:
365 *fmt
= AUDIO_FORMAT_S32
;
368 case SND_PCM_FORMAT_U32_BE
:
370 *fmt
= AUDIO_FORMAT_U32
;
374 dolog ("Unrecognized audio format %d\n", alsafmt
);
381 static void alsa_dump_info (struct alsa_params_req
*req
,
382 struct alsa_params_obt
*obt
,
383 snd_pcm_format_t obtfmt
,
384 AudiodevAlsaPerDirectionOptions
*apdo
)
386 dolog("parameter | requested value | obtained value\n");
387 dolog("format | %10d | %10d\n", req
->fmt
, obtfmt
);
388 dolog("channels | %10d | %10d\n",
389 req
->nchannels
, obt
->nchannels
);
390 dolog("frequency | %10d | %10d\n", req
->freq
, obt
->freq
);
391 dolog("============================================\n");
392 dolog("requested: buffer len %" PRId32
" period len %" PRId32
"\n",
393 apdo
->buffer_length
, apdo
->period_length
);
394 dolog("obtained: samples %ld\n", obt
->samples
);
397 static void alsa_set_threshold (snd_pcm_t
*handle
, snd_pcm_uframes_t threshold
)
400 snd_pcm_sw_params_t
*sw_params
;
402 snd_pcm_sw_params_alloca (&sw_params
);
404 err
= snd_pcm_sw_params_current (handle
, sw_params
);
406 dolog ("Could not fully initialize DAC\n");
407 alsa_logerr (err
, "Failed to get current software parameters\n");
411 err
= snd_pcm_sw_params_set_start_threshold (handle
, sw_params
, threshold
);
413 dolog ("Could not fully initialize DAC\n");
414 alsa_logerr (err
, "Failed to set software threshold to %ld\n",
419 err
= snd_pcm_sw_params (handle
, sw_params
);
421 dolog ("Could not fully initialize DAC\n");
422 alsa_logerr (err
, "Failed to set software parameters\n");
427 static int alsa_open(bool in
, struct alsa_params_req
*req
,
428 struct alsa_params_obt
*obt
, snd_pcm_t
**handlep
,
431 AudiodevAlsaOptions
*aopts
= &dev
->u
.alsa
;
432 AudiodevAlsaPerDirectionOptions
*apdo
= in
? aopts
->in
: aopts
->out
;
434 snd_pcm_hw_params_t
*hw_params
;
436 unsigned int freq
, nchannels
;
437 const char *pcm_name
= apdo
->has_dev
? apdo
->dev
: "default";
438 snd_pcm_uframes_t obt_buffer_size
;
439 const char *typ
= in
? "ADC" : "DAC";
440 snd_pcm_format_t obtfmt
;
443 nchannels
= req
->nchannels
;
445 snd_pcm_hw_params_alloca (&hw_params
);
450 in
? SND_PCM_STREAM_CAPTURE
: SND_PCM_STREAM_PLAYBACK
,
454 alsa_logerr2 (err
, typ
, "Failed to open `%s':\n", pcm_name
);
458 err
= snd_pcm_hw_params_any (handle
, hw_params
);
460 alsa_logerr2 (err
, typ
, "Failed to initialize hardware parameters\n");
464 err
= snd_pcm_hw_params_set_access (
467 SND_PCM_ACCESS_RW_INTERLEAVED
470 alsa_logerr2 (err
, typ
, "Failed to set access type\n");
474 err
= snd_pcm_hw_params_set_format (handle
, hw_params
, req
->fmt
);
476 alsa_logerr2 (err
, typ
, "Failed to set format %d\n", req
->fmt
);
479 err
= snd_pcm_hw_params_set_rate_near (handle
, hw_params
, &freq
, 0);
481 alsa_logerr2 (err
, typ
, "Failed to set frequency %d\n", req
->freq
);
485 err
= snd_pcm_hw_params_set_channels_near (
491 alsa_logerr2 (err
, typ
, "Failed to set number of channels %d\n",
496 if (nchannels
!= 1 && nchannels
!= 2) {
497 alsa_logerr2 (err
, typ
,
498 "Can not handle obtained number of channels %d\n",
503 if (apdo
->buffer_length
) {
505 unsigned int btime
= apdo
->buffer_length
;
507 err
= snd_pcm_hw_params_set_buffer_time_near(
508 handle
, hw_params
, &btime
, &dir
);
511 alsa_logerr2(err
, typ
, "Failed to set buffer time to %" PRId32
"\n",
512 apdo
->buffer_length
);
516 if (apdo
->has_buffer_length
&& btime
!= apdo
->buffer_length
) {
517 dolog("Requested buffer time %" PRId32
518 " was rejected, using %u\n", apdo
->buffer_length
, btime
);
522 if (apdo
->period_length
) {
524 unsigned int ptime
= apdo
->period_length
;
526 err
= snd_pcm_hw_params_set_period_time_near(handle
, hw_params
, &ptime
,
530 alsa_logerr2(err
, typ
, "Failed to set period time to %" PRId32
"\n",
531 apdo
->period_length
);
535 if (apdo
->has_period_length
&& ptime
!= apdo
->period_length
) {
536 dolog("Requested period time %" PRId32
" was rejected, using %d\n",
537 apdo
->period_length
, ptime
);
541 err
= snd_pcm_hw_params (handle
, hw_params
);
543 alsa_logerr2 (err
, typ
, "Failed to apply audio parameters\n");
547 err
= snd_pcm_hw_params_get_buffer_size (hw_params
, &obt_buffer_size
);
549 alsa_logerr2 (err
, typ
, "Failed to get buffer size\n");
553 err
= snd_pcm_hw_params_get_format (hw_params
, &obtfmt
);
555 alsa_logerr2 (err
, typ
, "Failed to get format\n");
559 if (alsa_to_audfmt (obtfmt
, &obt
->fmt
, &obt
->endianness
)) {
560 dolog ("Invalid format was returned %d\n", obtfmt
);
564 err
= snd_pcm_prepare (handle
);
566 alsa_logerr2 (err
, typ
, "Could not prepare handle %p\n", handle
);
570 if (!in
&& aopts
->has_threshold
&& aopts
->threshold
) {
571 struct audsettings as
= { .freq
= freq
};
574 audio_buffer_frames(qapi_AudiodevAlsaPerDirectionOptions_base(apdo
),
575 &as
, aopts
->threshold
));
578 obt
->nchannels
= nchannels
;
580 obt
->samples
= obt_buffer_size
;
584 if (obtfmt
!= req
->fmt
||
585 obt
->nchannels
!= req
->nchannels
||
586 obt
->freq
!= req
->freq
) {
587 dolog ("Audio parameters for %s\n", typ
);
588 alsa_dump_info(req
, obt
, obtfmt
, apdo
);
592 alsa_dump_info(req
, obt
, obtfmt
, pdo
);
597 alsa_anal_close1 (&handle
);
601 static size_t alsa_write(HWVoiceOut
*hw
, void *buf
, size_t len
)
603 ALSAVoiceOut
*alsa
= (ALSAVoiceOut
*) hw
;
605 size_t len_frames
= len
>> hw
->info
.shift
;
608 char *src
= advance(buf
, pos
);
609 snd_pcm_sframes_t written
;
611 written
= snd_pcm_writei(alsa
->handle
, src
, len_frames
);
616 trace_alsa_wrote_zero(len_frames
);
620 if (alsa_recover(alsa
->handle
)) {
621 alsa_logerr(written
, "Failed to write %zu frames\n",
625 trace_alsa_xrun_out();
630 * stream is suspended and waiting for an application
633 if (alsa_resume(alsa
->handle
)) {
634 alsa_logerr(written
, "Failed to write %zu frames\n",
638 trace_alsa_resume_out();
645 alsa_logerr(written
, "Failed to write %zu frames from %p\n",
651 pos
+= written
<< hw
->info
.shift
;
652 if (written
< len_frames
) {
655 len_frames
-= written
;
661 static void alsa_fini_out (HWVoiceOut
*hw
)
663 ALSAVoiceOut
*alsa
= (ALSAVoiceOut
*) hw
;
665 ldebug ("alsa_fini\n");
666 alsa_anal_close (&alsa
->handle
, &alsa
->pollhlp
);
669 static int alsa_init_out(HWVoiceOut
*hw
, struct audsettings
*as
,
672 ALSAVoiceOut
*alsa
= (ALSAVoiceOut
*) hw
;
673 struct alsa_params_req req
;
674 struct alsa_params_obt obt
;
676 struct audsettings obt_as
;
677 Audiodev
*dev
= drv_opaque
;
679 req
.fmt
= aud_to_alsafmt (as
->fmt
, as
->endianness
);
681 req
.nchannels
= as
->nchannels
;
683 if (alsa_open(0, &req
, &obt
, &handle
, dev
)) {
687 obt_as
.freq
= obt
.freq
;
688 obt_as
.nchannels
= obt
.nchannels
;
689 obt_as
.fmt
= obt
.fmt
;
690 obt_as
.endianness
= obt
.endianness
;
692 audio_pcm_init_info (&hw
->info
, &obt_as
);
693 hw
->samples
= obt
.samples
;
695 alsa
->pollhlp
.s
= hw
->s
;
696 alsa
->handle
= handle
;
701 #define VOICE_CTL_PAUSE 0
702 #define VOICE_CTL_PREPARE 1
703 #define VOICE_CTL_START 2
705 static int alsa_voice_ctl (snd_pcm_t
*handle
, const char *typ
, int ctl
)
709 if (ctl
== VOICE_CTL_PAUSE
) {
710 err
= snd_pcm_drop (handle
);
712 alsa_logerr (err
, "Could not stop %s\n", typ
);
717 err
= snd_pcm_prepare (handle
);
719 alsa_logerr (err
, "Could not prepare handle for %s\n", typ
);
722 if (ctl
== VOICE_CTL_START
) {
723 err
= snd_pcm_start(handle
);
725 alsa_logerr (err
, "Could not start handle for %s\n", typ
);
734 static void alsa_enable_out(HWVoiceOut
*hw
, bool enable
)
736 ALSAVoiceOut
*alsa
= (ALSAVoiceOut
*) hw
;
737 AudiodevAlsaPerDirectionOptions
*apdo
= alsa
->dev
->u
.alsa
.out
;
740 bool poll_mode
= apdo
->try_poll
;
742 ldebug("enabling voice\n");
743 if (poll_mode
&& alsa_poll_out(hw
)) {
746 hw
->poll_mode
= poll_mode
;
747 alsa_voice_ctl(alsa
->handle
, "playback", VOICE_CTL_PREPARE
);
749 ldebug("disabling voice\n");
752 alsa_fini_poll(&alsa
->pollhlp
);
754 alsa_voice_ctl(alsa
->handle
, "playback", VOICE_CTL_PAUSE
);
758 static int alsa_init_in(HWVoiceIn
*hw
, struct audsettings
*as
, void *drv_opaque
)
760 ALSAVoiceIn
*alsa
= (ALSAVoiceIn
*) hw
;
761 struct alsa_params_req req
;
762 struct alsa_params_obt obt
;
764 struct audsettings obt_as
;
765 Audiodev
*dev
= drv_opaque
;
767 req
.fmt
= aud_to_alsafmt (as
->fmt
, as
->endianness
);
769 req
.nchannels
= as
->nchannels
;
771 if (alsa_open(1, &req
, &obt
, &handle
, dev
)) {
775 obt_as
.freq
= obt
.freq
;
776 obt_as
.nchannels
= obt
.nchannels
;
777 obt_as
.fmt
= obt
.fmt
;
778 obt_as
.endianness
= obt
.endianness
;
780 audio_pcm_init_info (&hw
->info
, &obt_as
);
781 hw
->samples
= obt
.samples
;
783 alsa
->pollhlp
.s
= hw
->s
;
784 alsa
->handle
= handle
;
789 static void alsa_fini_in (HWVoiceIn
*hw
)
791 ALSAVoiceIn
*alsa
= (ALSAVoiceIn
*) hw
;
793 alsa_anal_close (&alsa
->handle
, &alsa
->pollhlp
);
796 static size_t alsa_read(HWVoiceIn
*hw
, void *buf
, size_t len
)
798 ALSAVoiceIn
*alsa
= (ALSAVoiceIn
*) hw
;
802 void *dst
= advance(buf
, pos
);
803 snd_pcm_sframes_t nread
;
805 nread
= snd_pcm_readi(alsa
->handle
, dst
, len
>> hw
->info
.shift
);
810 trace_alsa_read_zero(len
);
814 if (alsa_recover(alsa
->handle
)) {
815 alsa_logerr(nread
, "Failed to read %zu frames\n", len
);
818 trace_alsa_xrun_in();
825 alsa_logerr(nread
, "Failed to read %zu frames to %p\n",
831 pos
+= nread
<< hw
->info
.shift
;
832 len
-= nread
<< hw
->info
.shift
;
838 static void alsa_enable_in(HWVoiceIn
*hw
, bool enable
)
840 ALSAVoiceIn
*alsa
= (ALSAVoiceIn
*) hw
;
841 AudiodevAlsaPerDirectionOptions
*apdo
= alsa
->dev
->u
.alsa
.in
;
844 bool poll_mode
= apdo
->try_poll
;
846 ldebug("enabling voice\n");
847 if (poll_mode
&& alsa_poll_in(hw
)) {
850 hw
->poll_mode
= poll_mode
;
852 alsa_voice_ctl(alsa
->handle
, "capture", VOICE_CTL_START
);
854 ldebug ("disabling voice\n");
857 alsa_fini_poll(&alsa
->pollhlp
);
859 alsa_voice_ctl(alsa
->handle
, "capture", VOICE_CTL_PAUSE
);
863 static void alsa_init_per_direction(AudiodevAlsaPerDirectionOptions
*apdo
)
865 if (!apdo
->has_try_poll
) {
866 apdo
->try_poll
= true;
867 apdo
->has_try_poll
= true;
871 static void *alsa_audio_init(Audiodev
*dev
)
873 AudiodevAlsaOptions
*aopts
;
874 assert(dev
->driver
== AUDIODEV_DRIVER_ALSA
);
876 aopts
= &dev
->u
.alsa
;
877 alsa_init_per_direction(aopts
->in
);
878 alsa_init_per_direction(aopts
->out
);
881 * need to define them, as otherwise alsa produces no sound
882 * doesn't set has_* so alsa_open can identify it wasn't set by the user
884 if (!dev
->u
.alsa
.out
->has_period_length
) {
885 /* 1024 frames assuming 44100Hz */
886 dev
->u
.alsa
.out
->period_length
= 1024 * 1000000 / 44100;
888 if (!dev
->u
.alsa
.out
->has_buffer_length
) {
889 /* 4096 frames assuming 44100Hz */
890 dev
->u
.alsa
.out
->buffer_length
= 4096ll * 1000000 / 44100;
894 * OptsVisitor sets unspecified optional fields to zero, but do not depend
897 if (!dev
->u
.alsa
.in
->has_period_length
) {
898 dev
->u
.alsa
.in
->period_length
= 0;
900 if (!dev
->u
.alsa
.in
->has_buffer_length
) {
901 dev
->u
.alsa
.in
->buffer_length
= 0;
907 static void alsa_audio_fini (void *opaque
)
911 static struct audio_pcm_ops alsa_pcm_ops
= {
912 .init_out
= alsa_init_out
,
913 .fini_out
= alsa_fini_out
,
915 .enable_out
= alsa_enable_out
,
917 .init_in
= alsa_init_in
,
918 .fini_in
= alsa_fini_in
,
920 .enable_in
= alsa_enable_in
,
923 static struct audio_driver alsa_audio_driver
= {
925 .descr
= "ALSA http://www.alsa-project.org",
926 .init
= alsa_audio_init
,
927 .fini
= alsa_audio_fini
,
928 .pcm_ops
= &alsa_pcm_ops
,
930 .max_voices_out
= INT_MAX
,
931 .max_voices_in
= INT_MAX
,
932 .voice_size_out
= sizeof (ALSAVoiceOut
),
933 .voice_size_in
= sizeof (ALSAVoiceIn
)
936 static void register_audio_alsa(void)
938 audio_driver_register(&alsa_audio_driver
);
940 type_init(register_audio_alsa
);