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
24 #include "qemu/osdep.h"
25 #include <alsa/asoundlib.h>
26 #include "qemu-common.h"
27 #include "qemu/main-loop.h"
31 #if QEMU_GNUC_PREREQ(4, 3)
32 #pragma GCC diagnostic ignored "-Waddress"
35 #define AUDIO_CAP "alsa"
36 #include "audio_int.h"
38 typedef struct ALSAConf {
41 const char *pcm_name_in;
42 const char *pcm_name_out;
43 unsigned int buffer_size_in;
44 unsigned int period_size_in;
45 unsigned int buffer_size_out;
46 unsigned int period_size_out;
47 unsigned int threshold;
49 int buffer_size_in_overridden;
50 int period_size_in_overridden;
52 int buffer_size_out_overridden;
53 int period_size_out_overridden;
64 typedef struct ALSAVoiceOut {
70 struct pollhlp pollhlp;
73 typedef struct ALSAVoiceIn {
77 struct pollhlp pollhlp;
80 struct alsa_params_req {
86 unsigned int buffer_size;
87 unsigned int period_size;
90 struct alsa_params_obt {
95 snd_pcm_uframes_t samples;
98 static void GCC_FMT_ATTR (2, 3) alsa_logerr (int err, const char *fmt, ...)
103 AUD_vlog (AUDIO_CAP, fmt, ap);
106 AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
109 static void GCC_FMT_ATTR (3, 4) alsa_logerr2 (
118 AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ);
121 AUD_vlog (AUDIO_CAP, fmt, ap);
124 AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err));
127 static void alsa_fini_poll (struct pollhlp *hlp)
130 struct pollfd *pfds = hlp->pfds;
133 for (i = 0; i < hlp->count; ++i) {
134 qemu_set_fd_handler (pfds[i].fd, NULL, NULL, NULL);
143 static void alsa_anal_close1 (snd_pcm_t **handlep)
145 int err = snd_pcm_close (*handlep);
147 alsa_logerr (err, "Failed to close PCM handle %p\n", *handlep);
152 static void alsa_anal_close (snd_pcm_t **handlep, struct pollhlp *hlp)
154 alsa_fini_poll (hlp);
155 alsa_anal_close1 (handlep);
158 static int alsa_recover (snd_pcm_t *handle)
160 int err = snd_pcm_prepare (handle);
162 alsa_logerr (err, "Failed to prepare handle %p\n", handle);
168 static int alsa_resume (snd_pcm_t *handle)
170 int err = snd_pcm_resume (handle);
172 alsa_logerr (err, "Failed to resume handle %p\n", handle);
178 static void alsa_poll_handler (void *opaque)
181 snd_pcm_state_t state;
182 struct pollhlp *hlp = opaque;
183 unsigned short revents;
185 count = poll (hlp->pfds, hlp->count, 0);
187 dolog ("alsa_poll_handler: poll %s\n", strerror (errno));
195 /* XXX: ALSA example uses initial count, not the one returned by
197 err = snd_pcm_poll_descriptors_revents (hlp->handle, hlp->pfds,
198 hlp->count, &revents);
200 alsa_logerr (err, "snd_pcm_poll_descriptors_revents");
204 if (!(revents & hlp->mask)) {
205 trace_alsa_revents(revents);
209 state = snd_pcm_state (hlp->handle);
211 case SND_PCM_STATE_SETUP:
212 alsa_recover (hlp->handle);
215 case SND_PCM_STATE_XRUN:
216 alsa_recover (hlp->handle);
219 case SND_PCM_STATE_SUSPENDED:
220 alsa_resume (hlp->handle);
223 case SND_PCM_STATE_PREPARED:
224 audio_run ("alsa run (prepared)");
227 case SND_PCM_STATE_RUNNING:
228 audio_run ("alsa run (running)");
232 dolog ("Unexpected state %d\n", state);
236 static int alsa_poll_helper (snd_pcm_t *handle, struct pollhlp *hlp, int mask)
241 count = snd_pcm_poll_descriptors_count (handle);
243 dolog ("Could not initialize poll mode\n"
244 "Invalid number of poll descriptors %d\n", count);
248 pfds = audio_calloc ("alsa_poll_helper", count, sizeof (*pfds));
250 dolog ("Could not initialize poll mode\n");
254 err = snd_pcm_poll_descriptors (handle, pfds, count);
256 alsa_logerr (err, "Could not initialize poll mode\n"
257 "Could not obtain poll descriptors\n");
262 for (i = 0; i < count; ++i) {
263 if (pfds[i].events & POLLIN) {
264 qemu_set_fd_handler (pfds[i].fd, alsa_poll_handler, NULL, hlp);
266 if (pfds[i].events & POLLOUT) {
267 trace_alsa_pollout(i, pfds[i].fd);
268 qemu_set_fd_handler (pfds[i].fd, NULL, alsa_poll_handler, hlp);
270 trace_alsa_set_handler(pfds[i].events, i, pfds[i].fd, err);
275 hlp->handle = handle;
280 static int alsa_poll_out (HWVoiceOut *hw)
282 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
284 return alsa_poll_helper (alsa->handle, &alsa->pollhlp, POLLOUT);
287 static int alsa_poll_in (HWVoiceIn *hw)
289 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
291 return alsa_poll_helper (alsa->handle, &alsa->pollhlp, POLLIN);
294 static int alsa_write (SWVoiceOut *sw, void *buf, int len)
296 return audio_pcm_sw_write (sw, buf, len);
299 static snd_pcm_format_t aud_to_alsafmt (audfmt_e fmt, int endianness)
303 return SND_PCM_FORMAT_S8;
306 return SND_PCM_FORMAT_U8;
310 return SND_PCM_FORMAT_S16_BE;
313 return SND_PCM_FORMAT_S16_LE;
318 return SND_PCM_FORMAT_U16_BE;
321 return SND_PCM_FORMAT_U16_LE;
326 return SND_PCM_FORMAT_S32_BE;
329 return SND_PCM_FORMAT_S32_LE;
334 return SND_PCM_FORMAT_U32_BE;
337 return SND_PCM_FORMAT_U32_LE;
341 dolog ("Internal logic error: Bad audio format %d\n", fmt);
345 return SND_PCM_FORMAT_U8;
349 static int alsa_to_audfmt (snd_pcm_format_t alsafmt, audfmt_e *fmt,
353 case SND_PCM_FORMAT_S8:
358 case SND_PCM_FORMAT_U8:
363 case SND_PCM_FORMAT_S16_LE:
368 case SND_PCM_FORMAT_U16_LE:
373 case SND_PCM_FORMAT_S16_BE:
378 case SND_PCM_FORMAT_U16_BE:
383 case SND_PCM_FORMAT_S32_LE:
388 case SND_PCM_FORMAT_U32_LE:
393 case SND_PCM_FORMAT_S32_BE:
398 case SND_PCM_FORMAT_U32_BE:
404 dolog ("Unrecognized audio format %d\n", alsafmt);
411 static void alsa_dump_info (struct alsa_params_req *req,
412 struct alsa_params_obt *obt,
413 snd_pcm_format_t obtfmt)
415 dolog ("parameter | requested value | obtained value\n");
416 dolog ("format | %10d | %10d\n", req->fmt, obtfmt);
417 dolog ("channels | %10d | %10d\n",
418 req->nchannels, obt->nchannels);
419 dolog ("frequency | %10d | %10d\n", req->freq, obt->freq);
420 dolog ("============================================\n");
421 dolog ("requested: buffer size %d period size %d\n",
422 req->buffer_size, req->period_size);
423 dolog ("obtained: samples %ld\n", obt->samples);
426 static void alsa_set_threshold (snd_pcm_t *handle, snd_pcm_uframes_t threshold)
429 snd_pcm_sw_params_t *sw_params;
431 snd_pcm_sw_params_alloca (&sw_params);
433 err = snd_pcm_sw_params_current (handle, sw_params);
435 dolog ("Could not fully initialize DAC\n");
436 alsa_logerr (err, "Failed to get current software parameters\n");
440 err = snd_pcm_sw_params_set_start_threshold (handle, sw_params, threshold);
442 dolog ("Could not fully initialize DAC\n");
443 alsa_logerr (err, "Failed to set software threshold to %ld\n",
448 err = snd_pcm_sw_params (handle, sw_params);
450 dolog ("Could not fully initialize DAC\n");
451 alsa_logerr (err, "Failed to set software parameters\n");
456 static int alsa_open (int in, struct alsa_params_req *req,
457 struct alsa_params_obt *obt, snd_pcm_t **handlep,
461 snd_pcm_hw_params_t *hw_params;
464 unsigned int freq, nchannels;
465 const char *pcm_name = in ? conf->pcm_name_in : conf->pcm_name_out;
466 snd_pcm_uframes_t obt_buffer_size;
467 const char *typ = in ? "ADC" : "DAC";
468 snd_pcm_format_t obtfmt;
471 nchannels = req->nchannels;
472 size_in_usec = req->size_in_usec;
474 snd_pcm_hw_params_alloca (&hw_params);
479 in ? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK,
483 alsa_logerr2 (err, typ, "Failed to open `%s':\n", pcm_name);
487 err = snd_pcm_hw_params_any (handle, hw_params);
489 alsa_logerr2 (err, typ, "Failed to initialize hardware parameters\n");
493 err = snd_pcm_hw_params_set_access (
496 SND_PCM_ACCESS_RW_INTERLEAVED
499 alsa_logerr2 (err, typ, "Failed to set access type\n");
503 err = snd_pcm_hw_params_set_format (handle, hw_params, req->fmt);
505 alsa_logerr2 (err, typ, "Failed to set format %d\n", req->fmt);
508 err = snd_pcm_hw_params_set_rate_near (handle, hw_params, &freq, 0);
510 alsa_logerr2 (err, typ, "Failed to set frequency %d\n", req->freq);
514 err = snd_pcm_hw_params_set_channels_near (
520 alsa_logerr2 (err, typ, "Failed to set number of channels %d\n",
525 if (nchannels != 1 && nchannels != 2) {
526 alsa_logerr2 (err, typ,
527 "Can not handle obtained number of channels %d\n",
532 if (req->buffer_size) {
537 unsigned int btime = req->buffer_size;
539 err = snd_pcm_hw_params_set_buffer_time_near (
548 snd_pcm_uframes_t bsize = req->buffer_size;
550 err = snd_pcm_hw_params_set_buffer_size_near (
558 alsa_logerr2 (err, typ, "Failed to set buffer %s to %d\n",
559 size_in_usec ? "time" : "size", req->buffer_size);
563 if ((req->override_mask & 2) && (obt - req->buffer_size))
564 dolog ("Requested buffer %s %u was rejected, using %lu\n",
565 size_in_usec ? "time" : "size", req->buffer_size, obt);
568 if (req->period_size) {
573 unsigned int ptime = req->period_size;
575 err = snd_pcm_hw_params_set_period_time_near (
585 snd_pcm_uframes_t psize = req->period_size;
587 err = snd_pcm_hw_params_set_period_size_near (
597 alsa_logerr2 (err, typ, "Failed to set period %s to %d\n",
598 size_in_usec ? "time" : "size", req->period_size);
602 if (((req->override_mask & 1) && (obt - req->period_size)))
603 dolog ("Requested period %s %u was rejected, using %lu\n",
604 size_in_usec ? "time" : "size", req->period_size, obt);
607 err = snd_pcm_hw_params (handle, hw_params);
609 alsa_logerr2 (err, typ, "Failed to apply audio parameters\n");
613 err = snd_pcm_hw_params_get_buffer_size (hw_params, &obt_buffer_size);
615 alsa_logerr2 (err, typ, "Failed to get buffer size\n");
619 err = snd_pcm_hw_params_get_format (hw_params, &obtfmt);
621 alsa_logerr2 (err, typ, "Failed to get format\n");
625 if (alsa_to_audfmt (obtfmt, &obt->fmt, &obt->endianness)) {
626 dolog ("Invalid format was returned %d\n", obtfmt);
630 err = snd_pcm_prepare (handle);
632 alsa_logerr2 (err, typ, "Could not prepare handle %p\n", handle);
636 if (!in && conf->threshold) {
637 snd_pcm_uframes_t threshold;
640 bytes_per_sec = freq << (nchannels == 2);
658 threshold = (conf->threshold * bytes_per_sec) / 1000;
659 alsa_set_threshold (handle, threshold);
662 obt->nchannels = nchannels;
664 obt->samples = obt_buffer_size;
668 if (obtfmt != req->fmt ||
669 obt->nchannels != req->nchannels ||
670 obt->freq != req->freq) {
671 dolog ("Audio parameters for %s\n", typ);
672 alsa_dump_info (req, obt, obtfmt);
676 alsa_dump_info (req, obt, obtfmt);
681 alsa_anal_close1 (&handle);
685 static snd_pcm_sframes_t alsa_get_avail (snd_pcm_t *handle)
687 snd_pcm_sframes_t avail;
689 avail = snd_pcm_avail_update (handle);
691 if (avail == -EPIPE) {
692 if (!alsa_recover (handle)) {
693 avail = snd_pcm_avail_update (handle);
699 "Could not obtain number of available frames\n");
707 static void alsa_write_pending (ALSAVoiceOut *alsa)
709 HWVoiceOut *hw = &alsa->hw;
711 while (alsa->pending) {
712 int left_till_end_samples = hw->samples - alsa->wpos;
713 int len = audio_MIN (alsa->pending, left_till_end_samples);
714 char *src = advance (alsa->pcm_buf, alsa->wpos << hw->info.shift);
717 snd_pcm_sframes_t written;
719 written = snd_pcm_writei (alsa->handle, src, len);
724 trace_alsa_wrote_zero(len);
728 if (alsa_recover (alsa->handle)) {
729 alsa_logerr (written, "Failed to write %d frames\n",
733 trace_alsa_xrun_out();
737 /* stream is suspended and waiting for an
738 application recovery */
739 if (alsa_resume (alsa->handle)) {
740 alsa_logerr (written, "Failed to write %d frames\n",
744 trace_alsa_resume_out();
751 alsa_logerr (written, "Failed to write %d frames from %p\n",
757 alsa->wpos = (alsa->wpos + written) % hw->samples;
758 alsa->pending -= written;
764 static int alsa_run_out (HWVoiceOut *hw, int live)
766 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
768 snd_pcm_sframes_t avail;
770 avail = alsa_get_avail (alsa->handle);
772 dolog ("Could not get number of available playback frames\n");
776 decr = audio_MIN (live, avail);
777 decr = audio_pcm_hw_clip_out (hw, alsa->pcm_buf, decr, alsa->pending);
778 alsa->pending += decr;
779 alsa_write_pending (alsa);
783 static void alsa_fini_out (HWVoiceOut *hw)
785 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
787 ldebug ("alsa_fini\n");
788 alsa_anal_close (&alsa->handle, &alsa->pollhlp);
790 g_free(alsa->pcm_buf);
791 alsa->pcm_buf = NULL;
794 static int alsa_init_out(HWVoiceOut *hw, struct audsettings *as,
797 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
798 struct alsa_params_req req;
799 struct alsa_params_obt obt;
801 struct audsettings obt_as;
802 ALSAConf *conf = drv_opaque;
804 req.fmt = aud_to_alsafmt (as->fmt, as->endianness);
806 req.nchannels = as->nchannels;
807 req.period_size = conf->period_size_out;
808 req.buffer_size = conf->buffer_size_out;
809 req.size_in_usec = conf->size_in_usec_out;
811 (conf->period_size_out_overridden ? 1 : 0) |
812 (conf->buffer_size_out_overridden ? 2 : 0);
814 if (alsa_open (0, &req, &obt, &handle, conf)) {
818 obt_as.freq = obt.freq;
819 obt_as.nchannels = obt.nchannels;
820 obt_as.fmt = obt.fmt;
821 obt_as.endianness = obt.endianness;
823 audio_pcm_init_info (&hw->info, &obt_as);
824 hw->samples = obt.samples;
826 alsa->pcm_buf = audio_calloc(__func__, obt.samples, 1 << hw->info.shift);
827 if (!alsa->pcm_buf) {
828 dolog ("Could not allocate DAC buffer (%d samples, each %d bytes)\n",
829 hw->samples, 1 << hw->info.shift);
830 alsa_anal_close1 (&handle);
834 alsa->handle = handle;
835 alsa->pollhlp.conf = conf;
839 #define VOICE_CTL_PAUSE 0
840 #define VOICE_CTL_PREPARE 1
841 #define VOICE_CTL_START 2
843 static int alsa_voice_ctl (snd_pcm_t *handle, const char *typ, int ctl)
847 if (ctl == VOICE_CTL_PAUSE) {
848 err = snd_pcm_drop (handle);
850 alsa_logerr (err, "Could not stop %s\n", typ);
855 err = snd_pcm_prepare (handle);
857 alsa_logerr (err, "Could not prepare handle for %s\n", typ);
860 if (ctl == VOICE_CTL_START) {
861 err = snd_pcm_start(handle);
863 alsa_logerr (err, "Could not start handle for %s\n", typ);
872 static int alsa_ctl_out (HWVoiceOut *hw, int cmd, ...)
874 ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw;
883 poll_mode = va_arg (ap, int);
886 ldebug ("enabling voice\n");
887 if (poll_mode && alsa_poll_out (hw)) {
890 hw->poll_mode = poll_mode;
891 return alsa_voice_ctl (alsa->handle, "playback", VOICE_CTL_PREPARE);
895 ldebug ("disabling voice\n");
898 alsa_fini_poll (&alsa->pollhlp);
900 return alsa_voice_ctl (alsa->handle, "playback", VOICE_CTL_PAUSE);
906 static int alsa_init_in(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque)
908 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
909 struct alsa_params_req req;
910 struct alsa_params_obt obt;
912 struct audsettings obt_as;
913 ALSAConf *conf = drv_opaque;
915 req.fmt = aud_to_alsafmt (as->fmt, as->endianness);
917 req.nchannels = as->nchannels;
918 req.period_size = conf->period_size_in;
919 req.buffer_size = conf->buffer_size_in;
920 req.size_in_usec = conf->size_in_usec_in;
922 (conf->period_size_in_overridden ? 1 : 0) |
923 (conf->buffer_size_in_overridden ? 2 : 0);
925 if (alsa_open (1, &req, &obt, &handle, conf)) {
929 obt_as.freq = obt.freq;
930 obt_as.nchannels = obt.nchannels;
931 obt_as.fmt = obt.fmt;
932 obt_as.endianness = obt.endianness;
934 audio_pcm_init_info (&hw->info, &obt_as);
935 hw->samples = obt.samples;
937 alsa->pcm_buf = audio_calloc(__func__, hw->samples, 1 << hw->info.shift);
938 if (!alsa->pcm_buf) {
939 dolog ("Could not allocate ADC buffer (%d samples, each %d bytes)\n",
940 hw->samples, 1 << hw->info.shift);
941 alsa_anal_close1 (&handle);
945 alsa->handle = handle;
946 alsa->pollhlp.conf = conf;
950 static void alsa_fini_in (HWVoiceIn *hw)
952 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
954 alsa_anal_close (&alsa->handle, &alsa->pollhlp);
956 g_free(alsa->pcm_buf);
957 alsa->pcm_buf = NULL;
960 static int alsa_run_in (HWVoiceIn *hw)
962 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
963 int hwshift = hw->info.shift;
965 int live = audio_pcm_hw_get_live_in (hw);
966 int dead = hw->samples - live;
972 { .add = hw->wpos, .len = 0 },
973 { .add = 0, .len = 0 }
975 snd_pcm_sframes_t avail;
976 snd_pcm_uframes_t read_samples = 0;
982 avail = alsa_get_avail (alsa->handle);
984 dolog ("Could not get number of captured frames\n");
989 snd_pcm_state_t state;
991 state = snd_pcm_state (alsa->handle);
993 case SND_PCM_STATE_PREPARED:
996 case SND_PCM_STATE_SUSPENDED:
997 /* stream is suspended and waiting for an application recovery */
998 if (alsa_resume (alsa->handle)) {
999 dolog ("Failed to resume suspended input stream\n");
1002 trace_alsa_resume_in();
1005 trace_alsa_no_frames(state);
1010 decr = audio_MIN (dead, avail);
1015 if (hw->wpos + decr > hw->samples) {
1016 bufs[0].len = (hw->samples - hw->wpos);
1017 bufs[1].len = (decr - (hw->samples - hw->wpos));
1023 for (i = 0; i < 2; ++i) {
1025 struct st_sample *dst;
1026 snd_pcm_sframes_t nread;
1027 snd_pcm_uframes_t len;
1031 src = advance (alsa->pcm_buf, bufs[i].add << hwshift);
1032 dst = hw->conv_buf + bufs[i].add;
1035 nread = snd_pcm_readi (alsa->handle, src, len);
1040 trace_alsa_read_zero(len);
1044 if (alsa_recover (alsa->handle)) {
1045 alsa_logerr (nread, "Failed to read %ld frames\n", len);
1048 trace_alsa_xrun_in();
1057 "Failed to read %ld frames from %p\n",
1065 hw->conv (dst, src, nread);
1067 src = advance (src, nread << hwshift);
1070 read_samples += nread;
1076 hw->wpos = (hw->wpos + read_samples) % hw->samples;
1077 return read_samples;
1080 static int alsa_read (SWVoiceIn *sw, void *buf, int size)
1082 return audio_pcm_sw_read (sw, buf, size);
1085 static int alsa_ctl_in (HWVoiceIn *hw, int cmd, ...)
1087 ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw;
1096 poll_mode = va_arg (ap, int);
1099 ldebug ("enabling voice\n");
1100 if (poll_mode && alsa_poll_in (hw)) {
1103 hw->poll_mode = poll_mode;
1105 return alsa_voice_ctl (alsa->handle, "capture", VOICE_CTL_START);
1109 ldebug ("disabling voice\n");
1110 if (hw->poll_mode) {
1112 alsa_fini_poll (&alsa->pollhlp);
1114 return alsa_voice_ctl (alsa->handle, "capture", VOICE_CTL_PAUSE);
1120 static ALSAConf glob_conf = {
1121 .buffer_size_out = 4096,
1122 .period_size_out = 1024,
1123 .pcm_name_out = "default",
1124 .pcm_name_in = "default",
1127 static void *alsa_audio_init (void)
1129 ALSAConf *conf = g_malloc(sizeof(ALSAConf));
1134 static void alsa_audio_fini (void *opaque)
1139 static struct audio_option alsa_options[] = {
1141 .name = "DAC_SIZE_IN_USEC",
1142 .tag = AUD_OPT_BOOL,
1143 .valp = &glob_conf.size_in_usec_out,
1144 .descr = "DAC period/buffer size in microseconds (otherwise in frames)"
1147 .name = "DAC_PERIOD_SIZE",
1149 .valp = &glob_conf.period_size_out,
1150 .descr = "DAC period size (0 to go with system default)",
1151 .overriddenp = &glob_conf.period_size_out_overridden
1154 .name = "DAC_BUFFER_SIZE",
1156 .valp = &glob_conf.buffer_size_out,
1157 .descr = "DAC buffer size (0 to go with system default)",
1158 .overriddenp = &glob_conf.buffer_size_out_overridden
1161 .name = "ADC_SIZE_IN_USEC",
1162 .tag = AUD_OPT_BOOL,
1163 .valp = &glob_conf.size_in_usec_in,
1165 "ADC period/buffer size in microseconds (otherwise in frames)"
1168 .name = "ADC_PERIOD_SIZE",
1170 .valp = &glob_conf.period_size_in,
1171 .descr = "ADC period size (0 to go with system default)",
1172 .overriddenp = &glob_conf.period_size_in_overridden
1175 .name = "ADC_BUFFER_SIZE",
1177 .valp = &glob_conf.buffer_size_in,
1178 .descr = "ADC buffer size (0 to go with system default)",
1179 .overriddenp = &glob_conf.buffer_size_in_overridden
1182 .name = "THRESHOLD",
1184 .valp = &glob_conf.threshold,
1185 .descr = "(undocumented)"
1190 .valp = &glob_conf.pcm_name_out,
1191 .descr = "DAC device name (for instance dmix)"
1196 .valp = &glob_conf.pcm_name_in,
1197 .descr = "ADC device name"
1199 { /* End of list */ }
1202 static struct audio_pcm_ops alsa_pcm_ops = {
1203 .init_out = alsa_init_out,
1204 .fini_out = alsa_fini_out,
1205 .run_out = alsa_run_out,
1206 .write = alsa_write,
1207 .ctl_out = alsa_ctl_out,
1209 .init_in = alsa_init_in,
1210 .fini_in = alsa_fini_in,
1211 .run_in = alsa_run_in,
1213 .ctl_in = alsa_ctl_in,
1216 static struct audio_driver alsa_audio_driver = {
1218 .descr = "ALSA http://www.alsa-project.org",
1219 .options = alsa_options,
1220 .init = alsa_audio_init,
1221 .fini = alsa_audio_fini,
1222 .pcm_ops = &alsa_pcm_ops,
1223 .can_be_default = 1,
1224 .max_voices_out = INT_MAX,
1225 .max_voices_in = INT_MAX,
1226 .voice_size_out = sizeof (ALSAVoiceOut),
1227 .voice_size_in = sizeof (ALSAVoiceIn)
1230 static void register_audio_alsa(void)
1232 audio_driver_register(&alsa_audio_driver);
1234 type_init(register_audio_alsa);