|  | /* | 
|  | * QEMU ALSA audio driver | 
|  | * | 
|  | * Copyright (c) 2005 Vassili Karpov (malc) | 
|  | * | 
|  | * Permission is hereby granted, free of charge, to any person obtaining a copy | 
|  | * of this software and associated documentation files (the "Software"), to deal | 
|  | * in the Software without restriction, including without limitation the rights | 
|  | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | 
|  | * copies of the Software, and to permit persons to whom the Software is | 
|  | * furnished to do so, subject to the following conditions: | 
|  | * | 
|  | * The above copyright notice and this permission notice shall be included in | 
|  | * all copies or substantial portions of the Software. | 
|  | * | 
|  | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | 
|  | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | 
|  | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | 
|  | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | 
|  | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | 
|  | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | 
|  | * THE SOFTWARE. | 
|  | */ | 
|  | #include <alsa/asoundlib.h> | 
|  | #include "qemu-common.h" | 
|  | #include "qemu/main-loop.h" | 
|  | #include "audio.h" | 
|  |  | 
|  | #if QEMU_GNUC_PREREQ(4, 3) | 
|  | #pragma GCC diagnostic ignored "-Waddress" | 
|  | #endif | 
|  |  | 
|  | #define AUDIO_CAP "alsa" | 
|  | #include "audio_int.h" | 
|  |  | 
|  | struct pollhlp { | 
|  | snd_pcm_t *handle; | 
|  | struct pollfd *pfds; | 
|  | int count; | 
|  | int mask; | 
|  | }; | 
|  |  | 
|  | typedef struct ALSAVoiceOut { | 
|  | HWVoiceOut hw; | 
|  | int wpos; | 
|  | int pending; | 
|  | void *pcm_buf; | 
|  | snd_pcm_t *handle; | 
|  | struct pollhlp pollhlp; | 
|  | } ALSAVoiceOut; | 
|  |  | 
|  | typedef struct ALSAVoiceIn { | 
|  | HWVoiceIn hw; | 
|  | snd_pcm_t *handle; | 
|  | void *pcm_buf; | 
|  | struct pollhlp pollhlp; | 
|  | } ALSAVoiceIn; | 
|  |  | 
|  | static struct { | 
|  | int size_in_usec_in; | 
|  | int size_in_usec_out; | 
|  | const char *pcm_name_in; | 
|  | const char *pcm_name_out; | 
|  | unsigned int buffer_size_in; | 
|  | unsigned int period_size_in; | 
|  | unsigned int buffer_size_out; | 
|  | unsigned int period_size_out; | 
|  | unsigned int threshold; | 
|  |  | 
|  | int buffer_size_in_overridden; | 
|  | int period_size_in_overridden; | 
|  |  | 
|  | int buffer_size_out_overridden; | 
|  | int period_size_out_overridden; | 
|  | int verbose; | 
|  | } conf = { | 
|  | .buffer_size_out = 4096, | 
|  | .period_size_out = 1024, | 
|  | .pcm_name_out = "default", | 
|  | .pcm_name_in = "default", | 
|  | }; | 
|  |  | 
|  | struct alsa_params_req { | 
|  | int freq; | 
|  | snd_pcm_format_t fmt; | 
|  | int nchannels; | 
|  | int size_in_usec; | 
|  | int override_mask; | 
|  | unsigned int buffer_size; | 
|  | unsigned int period_size; | 
|  | }; | 
|  |  | 
|  | struct alsa_params_obt { | 
|  | int freq; | 
|  | audfmt_e fmt; | 
|  | int endianness; | 
|  | int nchannels; | 
|  | snd_pcm_uframes_t samples; | 
|  | }; | 
|  |  | 
|  | static void GCC_FMT_ATTR (2, 3) alsa_logerr (int err, const char *fmt, ...) | 
|  | { | 
|  | va_list ap; | 
|  |  | 
|  | va_start (ap, fmt); | 
|  | AUD_vlog (AUDIO_CAP, fmt, ap); | 
|  | va_end (ap); | 
|  |  | 
|  | AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err)); | 
|  | } | 
|  |  | 
|  | static void GCC_FMT_ATTR (3, 4) alsa_logerr2 ( | 
|  | int err, | 
|  | const char *typ, | 
|  | const char *fmt, | 
|  | ... | 
|  | ) | 
|  | { | 
|  | va_list ap; | 
|  |  | 
|  | AUD_log (AUDIO_CAP, "Could not initialize %s\n", typ); | 
|  |  | 
|  | va_start (ap, fmt); | 
|  | AUD_vlog (AUDIO_CAP, fmt, ap); | 
|  | va_end (ap); | 
|  |  | 
|  | AUD_log (AUDIO_CAP, "Reason: %s\n", snd_strerror (err)); | 
|  | } | 
|  |  | 
|  | static void alsa_fini_poll (struct pollhlp *hlp) | 
|  | { | 
|  | int i; | 
|  | struct pollfd *pfds = hlp->pfds; | 
|  |  | 
|  | if (pfds) { | 
|  | for (i = 0; i < hlp->count; ++i) { | 
|  | qemu_set_fd_handler (pfds[i].fd, NULL, NULL, NULL); | 
|  | } | 
|  | g_free (pfds); | 
|  | } | 
|  | hlp->pfds = NULL; | 
|  | hlp->count = 0; | 
|  | hlp->handle = NULL; | 
|  | } | 
|  |  | 
|  | static void alsa_anal_close1 (snd_pcm_t **handlep) | 
|  | { | 
|  | int err = snd_pcm_close (*handlep); | 
|  | if (err) { | 
|  | alsa_logerr (err, "Failed to close PCM handle %p\n", *handlep); | 
|  | } | 
|  | *handlep = NULL; | 
|  | } | 
|  |  | 
|  | static void alsa_anal_close (snd_pcm_t **handlep, struct pollhlp *hlp) | 
|  | { | 
|  | alsa_fini_poll (hlp); | 
|  | alsa_anal_close1 (handlep); | 
|  | } | 
|  |  | 
|  | static int alsa_recover (snd_pcm_t *handle) | 
|  | { | 
|  | int err = snd_pcm_prepare (handle); | 
|  | if (err < 0) { | 
|  | alsa_logerr (err, "Failed to prepare handle %p\n", handle); | 
|  | return -1; | 
|  | } | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int alsa_resume (snd_pcm_t *handle) | 
|  | { | 
|  | int err = snd_pcm_resume (handle); | 
|  | if (err < 0) { | 
|  | alsa_logerr (err, "Failed to resume handle %p\n", handle); | 
|  | return -1; | 
|  | } | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void alsa_poll_handler (void *opaque) | 
|  | { | 
|  | int err, count; | 
|  | snd_pcm_state_t state; | 
|  | struct pollhlp *hlp = opaque; | 
|  | unsigned short revents; | 
|  |  | 
|  | count = poll (hlp->pfds, hlp->count, 0); | 
|  | if (count < 0) { | 
|  | dolog ("alsa_poll_handler: poll %s\n", strerror (errno)); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (!count) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | /* XXX: ALSA example uses initial count, not the one returned by | 
|  | poll, correct? */ | 
|  | err = snd_pcm_poll_descriptors_revents (hlp->handle, hlp->pfds, | 
|  | hlp->count, &revents); | 
|  | if (err < 0) { | 
|  | alsa_logerr (err, "snd_pcm_poll_descriptors_revents"); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (!(revents & hlp->mask)) { | 
|  | if (conf.verbose) { | 
|  | dolog ("revents = %d\n", revents); | 
|  | } | 
|  | return; | 
|  | } | 
|  |  | 
|  | state = snd_pcm_state (hlp->handle); | 
|  | switch (state) { | 
|  | case SND_PCM_STATE_SETUP: | 
|  | alsa_recover (hlp->handle); | 
|  | break; | 
|  |  | 
|  | case SND_PCM_STATE_XRUN: | 
|  | alsa_recover (hlp->handle); | 
|  | break; | 
|  |  | 
|  | case SND_PCM_STATE_SUSPENDED: | 
|  | alsa_resume (hlp->handle); | 
|  | break; | 
|  |  | 
|  | case SND_PCM_STATE_PREPARED: | 
|  | audio_run ("alsa run (prepared)"); | 
|  | break; | 
|  |  | 
|  | case SND_PCM_STATE_RUNNING: | 
|  | audio_run ("alsa run (running)"); | 
|  | break; | 
|  |  | 
|  | default: | 
|  | dolog ("Unexpected state %d\n", state); | 
|  | } | 
|  | } | 
|  |  | 
|  | static int alsa_poll_helper (snd_pcm_t *handle, struct pollhlp *hlp, int mask) | 
|  | { | 
|  | int i, count, err; | 
|  | struct pollfd *pfds; | 
|  |  | 
|  | count = snd_pcm_poll_descriptors_count (handle); | 
|  | if (count <= 0) { | 
|  | dolog ("Could not initialize poll mode\n" | 
|  | "Invalid number of poll descriptors %d\n", count); | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | pfds = audio_calloc ("alsa_poll_helper", count, sizeof (*pfds)); | 
|  | if (!pfds) { | 
|  | dolog ("Could not initialize poll mode\n"); | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | err = snd_pcm_poll_descriptors (handle, pfds, count); | 
|  | if (err < 0) { | 
|  | alsa_logerr (err, "Could not initialize poll mode\n" | 
|  | "Could not obtain poll descriptors\n"); | 
|  | g_free (pfds); | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | for (i = 0; i < count; ++i) { | 
|  | if (pfds[i].events & POLLIN) { | 
|  | err = qemu_set_fd_handler (pfds[i].fd, alsa_poll_handler, | 
|  | NULL, hlp); | 
|  | } | 
|  | if (pfds[i].events & POLLOUT) { | 
|  | if (conf.verbose) { | 
|  | dolog ("POLLOUT %d %d\n", i, pfds[i].fd); | 
|  | } | 
|  | err = qemu_set_fd_handler (pfds[i].fd, NULL, | 
|  | alsa_poll_handler, hlp); | 
|  | } | 
|  | if (conf.verbose) { | 
|  | dolog ("Set handler events=%#x index=%d fd=%d err=%d\n", | 
|  | pfds[i].events, i, pfds[i].fd, err); | 
|  | } | 
|  |  | 
|  | if (err) { | 
|  | dolog ("Failed to set handler events=%#x index=%d fd=%d err=%d\n", | 
|  | pfds[i].events, i, pfds[i].fd, err); | 
|  |  | 
|  | while (i--) { | 
|  | qemu_set_fd_handler (pfds[i].fd, NULL, NULL, NULL); | 
|  | } | 
|  | g_free (pfds); | 
|  | return -1; | 
|  | } | 
|  | } | 
|  | hlp->pfds = pfds; | 
|  | hlp->count = count; | 
|  | hlp->handle = handle; | 
|  | hlp->mask = mask; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int alsa_poll_out (HWVoiceOut *hw) | 
|  | { | 
|  | ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw; | 
|  |  | 
|  | return alsa_poll_helper (alsa->handle, &alsa->pollhlp, POLLOUT); | 
|  | } | 
|  |  | 
|  | static int alsa_poll_in (HWVoiceIn *hw) | 
|  | { | 
|  | ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw; | 
|  |  | 
|  | return alsa_poll_helper (alsa->handle, &alsa->pollhlp, POLLIN); | 
|  | } | 
|  |  | 
|  | static int alsa_write (SWVoiceOut *sw, void *buf, int len) | 
|  | { | 
|  | return audio_pcm_sw_write (sw, buf, len); | 
|  | } | 
|  |  | 
|  | static snd_pcm_format_t aud_to_alsafmt (audfmt_e fmt, int endianness) | 
|  | { | 
|  | switch (fmt) { | 
|  | case AUD_FMT_S8: | 
|  | return SND_PCM_FORMAT_S8; | 
|  |  | 
|  | case AUD_FMT_U8: | 
|  | return SND_PCM_FORMAT_U8; | 
|  |  | 
|  | case AUD_FMT_S16: | 
|  | if (endianness) { | 
|  | return SND_PCM_FORMAT_S16_BE; | 
|  | } | 
|  | else { | 
|  | return SND_PCM_FORMAT_S16_LE; | 
|  | } | 
|  |  | 
|  | case AUD_FMT_U16: | 
|  | if (endianness) { | 
|  | return SND_PCM_FORMAT_U16_BE; | 
|  | } | 
|  | else { | 
|  | return SND_PCM_FORMAT_U16_LE; | 
|  | } | 
|  |  | 
|  | case AUD_FMT_S32: | 
|  | if (endianness) { | 
|  | return SND_PCM_FORMAT_S32_BE; | 
|  | } | 
|  | else { | 
|  | return SND_PCM_FORMAT_S32_LE; | 
|  | } | 
|  |  | 
|  | case AUD_FMT_U32: | 
|  | if (endianness) { | 
|  | return SND_PCM_FORMAT_U32_BE; | 
|  | } | 
|  | else { | 
|  | return SND_PCM_FORMAT_U32_LE; | 
|  | } | 
|  |  | 
|  | default: | 
|  | dolog ("Internal logic error: Bad audio format %d\n", fmt); | 
|  | #ifdef DEBUG_AUDIO | 
|  | abort (); | 
|  | #endif | 
|  | return SND_PCM_FORMAT_U8; | 
|  | } | 
|  | } | 
|  |  | 
|  | static int alsa_to_audfmt (snd_pcm_format_t alsafmt, audfmt_e *fmt, | 
|  | int *endianness) | 
|  | { | 
|  | switch (alsafmt) { | 
|  | case SND_PCM_FORMAT_S8: | 
|  | *endianness = 0; | 
|  | *fmt = AUD_FMT_S8; | 
|  | break; | 
|  |  | 
|  | case SND_PCM_FORMAT_U8: | 
|  | *endianness = 0; | 
|  | *fmt = AUD_FMT_U8; | 
|  | break; | 
|  |  | 
|  | case SND_PCM_FORMAT_S16_LE: | 
|  | *endianness = 0; | 
|  | *fmt = AUD_FMT_S16; | 
|  | break; | 
|  |  | 
|  | case SND_PCM_FORMAT_U16_LE: | 
|  | *endianness = 0; | 
|  | *fmt = AUD_FMT_U16; | 
|  | break; | 
|  |  | 
|  | case SND_PCM_FORMAT_S16_BE: | 
|  | *endianness = 1; | 
|  | *fmt = AUD_FMT_S16; | 
|  | break; | 
|  |  | 
|  | case SND_PCM_FORMAT_U16_BE: | 
|  | *endianness = 1; | 
|  | *fmt = AUD_FMT_U16; | 
|  | break; | 
|  |  | 
|  | case SND_PCM_FORMAT_S32_LE: | 
|  | *endianness = 0; | 
|  | *fmt = AUD_FMT_S32; | 
|  | break; | 
|  |  | 
|  | case SND_PCM_FORMAT_U32_LE: | 
|  | *endianness = 0; | 
|  | *fmt = AUD_FMT_U32; | 
|  | break; | 
|  |  | 
|  | case SND_PCM_FORMAT_S32_BE: | 
|  | *endianness = 1; | 
|  | *fmt = AUD_FMT_S32; | 
|  | break; | 
|  |  | 
|  | case SND_PCM_FORMAT_U32_BE: | 
|  | *endianness = 1; | 
|  | *fmt = AUD_FMT_U32; | 
|  | break; | 
|  |  | 
|  | default: | 
|  | dolog ("Unrecognized audio format %d\n", alsafmt); | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void alsa_dump_info (struct alsa_params_req *req, | 
|  | struct alsa_params_obt *obt, | 
|  | snd_pcm_format_t obtfmt) | 
|  | { | 
|  | dolog ("parameter | requested value | obtained value\n"); | 
|  | dolog ("format    |      %10d |     %10d\n", req->fmt, obtfmt); | 
|  | dolog ("channels  |      %10d |     %10d\n", | 
|  | req->nchannels, obt->nchannels); | 
|  | dolog ("frequency |      %10d |     %10d\n", req->freq, obt->freq); | 
|  | dolog ("============================================\n"); | 
|  | dolog ("requested: buffer size %d period size %d\n", | 
|  | req->buffer_size, req->period_size); | 
|  | dolog ("obtained: samples %ld\n", obt->samples); | 
|  | } | 
|  |  | 
|  | static void alsa_set_threshold (snd_pcm_t *handle, snd_pcm_uframes_t threshold) | 
|  | { | 
|  | int err; | 
|  | snd_pcm_sw_params_t *sw_params; | 
|  |  | 
|  | snd_pcm_sw_params_alloca (&sw_params); | 
|  |  | 
|  | err = snd_pcm_sw_params_current (handle, sw_params); | 
|  | if (err < 0) { | 
|  | dolog ("Could not fully initialize DAC\n"); | 
|  | alsa_logerr (err, "Failed to get current software parameters\n"); | 
|  | return; | 
|  | } | 
|  |  | 
|  | err = snd_pcm_sw_params_set_start_threshold (handle, sw_params, threshold); | 
|  | if (err < 0) { | 
|  | dolog ("Could not fully initialize DAC\n"); | 
|  | alsa_logerr (err, "Failed to set software threshold to %ld\n", | 
|  | threshold); | 
|  | return; | 
|  | } | 
|  |  | 
|  | err = snd_pcm_sw_params (handle, sw_params); | 
|  | if (err < 0) { | 
|  | dolog ("Could not fully initialize DAC\n"); | 
|  | alsa_logerr (err, "Failed to set software parameters\n"); | 
|  | return; | 
|  | } | 
|  | } | 
|  |  | 
|  | static int alsa_open (int in, struct alsa_params_req *req, | 
|  | struct alsa_params_obt *obt, snd_pcm_t **handlep) | 
|  | { | 
|  | snd_pcm_t *handle; | 
|  | snd_pcm_hw_params_t *hw_params; | 
|  | int err; | 
|  | int size_in_usec; | 
|  | unsigned int freq, nchannels; | 
|  | const char *pcm_name = in ? conf.pcm_name_in : conf.pcm_name_out; | 
|  | snd_pcm_uframes_t obt_buffer_size; | 
|  | const char *typ = in ? "ADC" : "DAC"; | 
|  | snd_pcm_format_t obtfmt; | 
|  |  | 
|  | freq = req->freq; | 
|  | nchannels = req->nchannels; | 
|  | size_in_usec = req->size_in_usec; | 
|  |  | 
|  | snd_pcm_hw_params_alloca (&hw_params); | 
|  |  | 
|  | err = snd_pcm_open ( | 
|  | &handle, | 
|  | pcm_name, | 
|  | in ? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK, | 
|  | SND_PCM_NONBLOCK | 
|  | ); | 
|  | if (err < 0) { | 
|  | alsa_logerr2 (err, typ, "Failed to open `%s':\n", pcm_name); | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | err = snd_pcm_hw_params_any (handle, hw_params); | 
|  | if (err < 0) { | 
|  | alsa_logerr2 (err, typ, "Failed to initialize hardware parameters\n"); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | err = snd_pcm_hw_params_set_access ( | 
|  | handle, | 
|  | hw_params, | 
|  | SND_PCM_ACCESS_RW_INTERLEAVED | 
|  | ); | 
|  | if (err < 0) { | 
|  | alsa_logerr2 (err, typ, "Failed to set access type\n"); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | err = snd_pcm_hw_params_set_format (handle, hw_params, req->fmt); | 
|  | if (err < 0 && conf.verbose) { | 
|  | alsa_logerr2 (err, typ, "Failed to set format %d\n", req->fmt); | 
|  | } | 
|  |  | 
|  | err = snd_pcm_hw_params_set_rate_near (handle, hw_params, &freq, 0); | 
|  | if (err < 0) { | 
|  | alsa_logerr2 (err, typ, "Failed to set frequency %d\n", req->freq); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | err = snd_pcm_hw_params_set_channels_near ( | 
|  | handle, | 
|  | hw_params, | 
|  | &nchannels | 
|  | ); | 
|  | if (err < 0) { | 
|  | alsa_logerr2 (err, typ, "Failed to set number of channels %d\n", | 
|  | req->nchannels); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | if (nchannels != 1 && nchannels != 2) { | 
|  | alsa_logerr2 (err, typ, | 
|  | "Can not handle obtained number of channels %d\n", | 
|  | nchannels); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | if (req->buffer_size) { | 
|  | unsigned long obt; | 
|  |  | 
|  | if (size_in_usec) { | 
|  | int dir = 0; | 
|  | unsigned int btime = req->buffer_size; | 
|  |  | 
|  | err = snd_pcm_hw_params_set_buffer_time_near ( | 
|  | handle, | 
|  | hw_params, | 
|  | &btime, | 
|  | &dir | 
|  | ); | 
|  | obt = btime; | 
|  | } | 
|  | else { | 
|  | snd_pcm_uframes_t bsize = req->buffer_size; | 
|  |  | 
|  | err = snd_pcm_hw_params_set_buffer_size_near ( | 
|  | handle, | 
|  | hw_params, | 
|  | &bsize | 
|  | ); | 
|  | obt = bsize; | 
|  | } | 
|  | if (err < 0) { | 
|  | alsa_logerr2 (err, typ, "Failed to set buffer %s to %d\n", | 
|  | size_in_usec ? "time" : "size", req->buffer_size); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | if ((req->override_mask & 2) && (obt - req->buffer_size)) | 
|  | dolog ("Requested buffer %s %u was rejected, using %lu\n", | 
|  | size_in_usec ? "time" : "size", req->buffer_size, obt); | 
|  | } | 
|  |  | 
|  | if (req->period_size) { | 
|  | unsigned long obt; | 
|  |  | 
|  | if (size_in_usec) { | 
|  | int dir = 0; | 
|  | unsigned int ptime = req->period_size; | 
|  |  | 
|  | err = snd_pcm_hw_params_set_period_time_near ( | 
|  | handle, | 
|  | hw_params, | 
|  | &ptime, | 
|  | &dir | 
|  | ); | 
|  | obt = ptime; | 
|  | } | 
|  | else { | 
|  | int dir = 0; | 
|  | snd_pcm_uframes_t psize = req->period_size; | 
|  |  | 
|  | err = snd_pcm_hw_params_set_period_size_near ( | 
|  | handle, | 
|  | hw_params, | 
|  | &psize, | 
|  | &dir | 
|  | ); | 
|  | obt = psize; | 
|  | } | 
|  |  | 
|  | if (err < 0) { | 
|  | alsa_logerr2 (err, typ, "Failed to set period %s to %d\n", | 
|  | size_in_usec ? "time" : "size", req->period_size); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | if (((req->override_mask & 1) && (obt - req->period_size))) | 
|  | dolog ("Requested period %s %u was rejected, using %lu\n", | 
|  | size_in_usec ? "time" : "size", req->period_size, obt); | 
|  | } | 
|  |  | 
|  | err = snd_pcm_hw_params (handle, hw_params); | 
|  | if (err < 0) { | 
|  | alsa_logerr2 (err, typ, "Failed to apply audio parameters\n"); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | err = snd_pcm_hw_params_get_buffer_size (hw_params, &obt_buffer_size); | 
|  | if (err < 0) { | 
|  | alsa_logerr2 (err, typ, "Failed to get buffer size\n"); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | err = snd_pcm_hw_params_get_format (hw_params, &obtfmt); | 
|  | if (err < 0) { | 
|  | alsa_logerr2 (err, typ, "Failed to get format\n"); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | if (alsa_to_audfmt (obtfmt, &obt->fmt, &obt->endianness)) { | 
|  | dolog ("Invalid format was returned %d\n", obtfmt); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | err = snd_pcm_prepare (handle); | 
|  | if (err < 0) { | 
|  | alsa_logerr2 (err, typ, "Could not prepare handle %p\n", handle); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | if (!in && conf.threshold) { | 
|  | snd_pcm_uframes_t threshold; | 
|  | int bytes_per_sec; | 
|  |  | 
|  | bytes_per_sec = freq << (nchannels == 2); | 
|  |  | 
|  | switch (obt->fmt) { | 
|  | case AUD_FMT_S8: | 
|  | case AUD_FMT_U8: | 
|  | break; | 
|  |  | 
|  | case AUD_FMT_S16: | 
|  | case AUD_FMT_U16: | 
|  | bytes_per_sec <<= 1; | 
|  | break; | 
|  |  | 
|  | case AUD_FMT_S32: | 
|  | case AUD_FMT_U32: | 
|  | bytes_per_sec <<= 2; | 
|  | break; | 
|  | } | 
|  |  | 
|  | threshold = (conf.threshold * bytes_per_sec) / 1000; | 
|  | alsa_set_threshold (handle, threshold); | 
|  | } | 
|  |  | 
|  | obt->nchannels = nchannels; | 
|  | obt->freq = freq; | 
|  | obt->samples = obt_buffer_size; | 
|  |  | 
|  | *handlep = handle; | 
|  |  | 
|  | if (conf.verbose && | 
|  | (obtfmt != req->fmt || | 
|  | obt->nchannels != req->nchannels || | 
|  | obt->freq != req->freq)) { | 
|  | dolog ("Audio parameters for %s\n", typ); | 
|  | alsa_dump_info (req, obt, obtfmt); | 
|  | } | 
|  |  | 
|  | #ifdef DEBUG | 
|  | alsa_dump_info (req, obt, obtfmt); | 
|  | #endif | 
|  | return 0; | 
|  |  | 
|  | err: | 
|  | alsa_anal_close1 (&handle); | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | static snd_pcm_sframes_t alsa_get_avail (snd_pcm_t *handle) | 
|  | { | 
|  | snd_pcm_sframes_t avail; | 
|  |  | 
|  | avail = snd_pcm_avail_update (handle); | 
|  | if (avail < 0) { | 
|  | if (avail == -EPIPE) { | 
|  | if (!alsa_recover (handle)) { | 
|  | avail = snd_pcm_avail_update (handle); | 
|  | } | 
|  | } | 
|  |  | 
|  | if (avail < 0) { | 
|  | alsa_logerr (avail, | 
|  | "Could not obtain number of available frames\n"); | 
|  | return -1; | 
|  | } | 
|  | } | 
|  |  | 
|  | return avail; | 
|  | } | 
|  |  | 
|  | static void alsa_write_pending (ALSAVoiceOut *alsa) | 
|  | { | 
|  | HWVoiceOut *hw = &alsa->hw; | 
|  |  | 
|  | while (alsa->pending) { | 
|  | int left_till_end_samples = hw->samples - alsa->wpos; | 
|  | int len = audio_MIN (alsa->pending, left_till_end_samples); | 
|  | char *src = advance (alsa->pcm_buf, alsa->wpos << hw->info.shift); | 
|  |  | 
|  | while (len) { | 
|  | snd_pcm_sframes_t written; | 
|  |  | 
|  | written = snd_pcm_writei (alsa->handle, src, len); | 
|  |  | 
|  | if (written <= 0) { | 
|  | switch (written) { | 
|  | case 0: | 
|  | if (conf.verbose) { | 
|  | dolog ("Failed to write %d frames (wrote zero)\n", len); | 
|  | } | 
|  | return; | 
|  |  | 
|  | case -EPIPE: | 
|  | if (alsa_recover (alsa->handle)) { | 
|  | alsa_logerr (written, "Failed to write %d frames\n", | 
|  | len); | 
|  | return; | 
|  | } | 
|  | if (conf.verbose) { | 
|  | dolog ("Recovering from playback xrun\n"); | 
|  | } | 
|  | continue; | 
|  |  | 
|  | case -ESTRPIPE: | 
|  | /* stream is suspended and waiting for an | 
|  | application recovery */ | 
|  | if (alsa_resume (alsa->handle)) { | 
|  | alsa_logerr (written, "Failed to write %d frames\n", | 
|  | len); | 
|  | return; | 
|  | } | 
|  | if (conf.verbose) { | 
|  | dolog ("Resuming suspended output stream\n"); | 
|  | } | 
|  | continue; | 
|  |  | 
|  | case -EAGAIN: | 
|  | return; | 
|  |  | 
|  | default: | 
|  | alsa_logerr (written, "Failed to write %d frames from %p\n", | 
|  | len, src); | 
|  | return; | 
|  | } | 
|  | } | 
|  |  | 
|  | alsa->wpos = (alsa->wpos + written) % hw->samples; | 
|  | alsa->pending -= written; | 
|  | len -= written; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | static int alsa_run_out (HWVoiceOut *hw, int live) | 
|  | { | 
|  | ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw; | 
|  | int decr; | 
|  | snd_pcm_sframes_t avail; | 
|  |  | 
|  | avail = alsa_get_avail (alsa->handle); | 
|  | if (avail < 0) { | 
|  | dolog ("Could not get number of available playback frames\n"); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | decr = audio_MIN (live, avail); | 
|  | decr = audio_pcm_hw_clip_out (hw, alsa->pcm_buf, decr, alsa->pending); | 
|  | alsa->pending += decr; | 
|  | alsa_write_pending (alsa); | 
|  | return decr; | 
|  | } | 
|  |  | 
|  | static void alsa_fini_out (HWVoiceOut *hw) | 
|  | { | 
|  | ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw; | 
|  |  | 
|  | ldebug ("alsa_fini\n"); | 
|  | alsa_anal_close (&alsa->handle, &alsa->pollhlp); | 
|  |  | 
|  | if (alsa->pcm_buf) { | 
|  | g_free (alsa->pcm_buf); | 
|  | alsa->pcm_buf = NULL; | 
|  | } | 
|  | } | 
|  |  | 
|  | static int alsa_init_out (HWVoiceOut *hw, struct audsettings *as) | 
|  | { | 
|  | ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw; | 
|  | struct alsa_params_req req; | 
|  | struct alsa_params_obt obt; | 
|  | snd_pcm_t *handle; | 
|  | struct audsettings obt_as; | 
|  |  | 
|  | req.fmt = aud_to_alsafmt (as->fmt, as->endianness); | 
|  | req.freq = as->freq; | 
|  | req.nchannels = as->nchannels; | 
|  | req.period_size = conf.period_size_out; | 
|  | req.buffer_size = conf.buffer_size_out; | 
|  | req.size_in_usec = conf.size_in_usec_out; | 
|  | req.override_mask = | 
|  | (conf.period_size_out_overridden ? 1 : 0) | | 
|  | (conf.buffer_size_out_overridden ? 2 : 0); | 
|  |  | 
|  | if (alsa_open (0, &req, &obt, &handle)) { | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | obt_as.freq = obt.freq; | 
|  | obt_as.nchannels = obt.nchannels; | 
|  | obt_as.fmt = obt.fmt; | 
|  | obt_as.endianness = obt.endianness; | 
|  |  | 
|  | audio_pcm_init_info (&hw->info, &obt_as); | 
|  | hw->samples = obt.samples; | 
|  |  | 
|  | alsa->pcm_buf = audio_calloc (AUDIO_FUNC, obt.samples, 1 << hw->info.shift); | 
|  | if (!alsa->pcm_buf) { | 
|  | dolog ("Could not allocate DAC buffer (%d samples, each %d bytes)\n", | 
|  | hw->samples, 1 << hw->info.shift); | 
|  | alsa_anal_close1 (&handle); | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | alsa->handle = handle; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | #define VOICE_CTL_PAUSE 0 | 
|  | #define VOICE_CTL_PREPARE 1 | 
|  | #define VOICE_CTL_START 2 | 
|  |  | 
|  | static int alsa_voice_ctl (snd_pcm_t *handle, const char *typ, int ctl) | 
|  | { | 
|  | int err; | 
|  |  | 
|  | if (ctl == VOICE_CTL_PAUSE) { | 
|  | err = snd_pcm_drop (handle); | 
|  | if (err < 0) { | 
|  | alsa_logerr (err, "Could not stop %s\n", typ); | 
|  | return -1; | 
|  | } | 
|  | } | 
|  | else { | 
|  | err = snd_pcm_prepare (handle); | 
|  | if (err < 0) { | 
|  | alsa_logerr (err, "Could not prepare handle for %s\n", typ); | 
|  | return -1; | 
|  | } | 
|  | if (ctl == VOICE_CTL_START) { | 
|  | err = snd_pcm_start(handle); | 
|  | if (err < 0) { | 
|  | alsa_logerr (err, "Could not start handle for %s\n", typ); | 
|  | return -1; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int alsa_ctl_out (HWVoiceOut *hw, int cmd, ...) | 
|  | { | 
|  | ALSAVoiceOut *alsa = (ALSAVoiceOut *) hw; | 
|  |  | 
|  | switch (cmd) { | 
|  | case VOICE_ENABLE: | 
|  | { | 
|  | va_list ap; | 
|  | int poll_mode; | 
|  |  | 
|  | va_start (ap, cmd); | 
|  | poll_mode = va_arg (ap, int); | 
|  | va_end (ap); | 
|  |  | 
|  | ldebug ("enabling voice\n"); | 
|  | if (poll_mode && alsa_poll_out (hw)) { | 
|  | poll_mode = 0; | 
|  | } | 
|  | hw->poll_mode = poll_mode; | 
|  | return alsa_voice_ctl (alsa->handle, "playback", VOICE_CTL_PREPARE); | 
|  | } | 
|  |  | 
|  | case VOICE_DISABLE: | 
|  | ldebug ("disabling voice\n"); | 
|  | if (hw->poll_mode) { | 
|  | hw->poll_mode = 0; | 
|  | alsa_fini_poll (&alsa->pollhlp); | 
|  | } | 
|  | return alsa_voice_ctl (alsa->handle, "playback", VOICE_CTL_PAUSE); | 
|  | } | 
|  |  | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | static int alsa_init_in (HWVoiceIn *hw, struct audsettings *as) | 
|  | { | 
|  | ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw; | 
|  | struct alsa_params_req req; | 
|  | struct alsa_params_obt obt; | 
|  | snd_pcm_t *handle; | 
|  | struct audsettings obt_as; | 
|  |  | 
|  | req.fmt = aud_to_alsafmt (as->fmt, as->endianness); | 
|  | req.freq = as->freq; | 
|  | req.nchannels = as->nchannels; | 
|  | req.period_size = conf.period_size_in; | 
|  | req.buffer_size = conf.buffer_size_in; | 
|  | req.size_in_usec = conf.size_in_usec_in; | 
|  | req.override_mask = | 
|  | (conf.period_size_in_overridden ? 1 : 0) | | 
|  | (conf.buffer_size_in_overridden ? 2 : 0); | 
|  |  | 
|  | if (alsa_open (1, &req, &obt, &handle)) { | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | obt_as.freq = obt.freq; | 
|  | obt_as.nchannels = obt.nchannels; | 
|  | obt_as.fmt = obt.fmt; | 
|  | obt_as.endianness = obt.endianness; | 
|  |  | 
|  | audio_pcm_init_info (&hw->info, &obt_as); | 
|  | hw->samples = obt.samples; | 
|  |  | 
|  | alsa->pcm_buf = audio_calloc (AUDIO_FUNC, hw->samples, 1 << hw->info.shift); | 
|  | if (!alsa->pcm_buf) { | 
|  | dolog ("Could not allocate ADC buffer (%d samples, each %d bytes)\n", | 
|  | hw->samples, 1 << hw->info.shift); | 
|  | alsa_anal_close1 (&handle); | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | alsa->handle = handle; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void alsa_fini_in (HWVoiceIn *hw) | 
|  | { | 
|  | ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw; | 
|  |  | 
|  | alsa_anal_close (&alsa->handle, &alsa->pollhlp); | 
|  |  | 
|  | if (alsa->pcm_buf) { | 
|  | g_free (alsa->pcm_buf); | 
|  | alsa->pcm_buf = NULL; | 
|  | } | 
|  | } | 
|  |  | 
|  | static int alsa_run_in (HWVoiceIn *hw) | 
|  | { | 
|  | ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw; | 
|  | int hwshift = hw->info.shift; | 
|  | int i; | 
|  | int live = audio_pcm_hw_get_live_in (hw); | 
|  | int dead = hw->samples - live; | 
|  | int decr; | 
|  | struct { | 
|  | int add; | 
|  | int len; | 
|  | } bufs[2] = { | 
|  | { .add = hw->wpos, .len = 0 }, | 
|  | { .add = 0,        .len = 0 } | 
|  | }; | 
|  | snd_pcm_sframes_t avail; | 
|  | snd_pcm_uframes_t read_samples = 0; | 
|  |  | 
|  | if (!dead) { | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | avail = alsa_get_avail (alsa->handle); | 
|  | if (avail < 0) { | 
|  | dolog ("Could not get number of captured frames\n"); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (!avail) { | 
|  | snd_pcm_state_t state; | 
|  |  | 
|  | state = snd_pcm_state (alsa->handle); | 
|  | switch (state) { | 
|  | case SND_PCM_STATE_PREPARED: | 
|  | avail = hw->samples; | 
|  | break; | 
|  | case SND_PCM_STATE_SUSPENDED: | 
|  | /* stream is suspended and waiting for an application recovery */ | 
|  | if (alsa_resume (alsa->handle)) { | 
|  | dolog ("Failed to resume suspended input stream\n"); | 
|  | return 0; | 
|  | } | 
|  | if (conf.verbose) { | 
|  | dolog ("Resuming suspended input stream\n"); | 
|  | } | 
|  | break; | 
|  | default: | 
|  | if (conf.verbose) { | 
|  | dolog ("No frames available and ALSA state is %d\n", state); | 
|  | } | 
|  | return 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | decr = audio_MIN (dead, avail); | 
|  | if (!decr) { | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (hw->wpos + decr > hw->samples) { | 
|  | bufs[0].len = (hw->samples - hw->wpos); | 
|  | bufs[1].len = (decr - (hw->samples - hw->wpos)); | 
|  | } | 
|  | else { | 
|  | bufs[0].len = decr; | 
|  | } | 
|  |  | 
|  | for (i = 0; i < 2; ++i) { | 
|  | void *src; | 
|  | struct st_sample *dst; | 
|  | snd_pcm_sframes_t nread; | 
|  | snd_pcm_uframes_t len; | 
|  |  | 
|  | len = bufs[i].len; | 
|  |  | 
|  | src = advance (alsa->pcm_buf, bufs[i].add << hwshift); | 
|  | dst = hw->conv_buf + bufs[i].add; | 
|  |  | 
|  | while (len) { | 
|  | nread = snd_pcm_readi (alsa->handle, src, len); | 
|  |  | 
|  | if (nread <= 0) { | 
|  | switch (nread) { | 
|  | case 0: | 
|  | if (conf.verbose) { | 
|  | dolog ("Failed to read %ld frames (read zero)\n", len); | 
|  | } | 
|  | goto exit; | 
|  |  | 
|  | case -EPIPE: | 
|  | if (alsa_recover (alsa->handle)) { | 
|  | alsa_logerr (nread, "Failed to read %ld frames\n", len); | 
|  | goto exit; | 
|  | } | 
|  | if (conf.verbose) { | 
|  | dolog ("Recovering from capture xrun\n"); | 
|  | } | 
|  | continue; | 
|  |  | 
|  | case -EAGAIN: | 
|  | goto exit; | 
|  |  | 
|  | default: | 
|  | alsa_logerr ( | 
|  | nread, | 
|  | "Failed to read %ld frames from %p\n", | 
|  | len, | 
|  | src | 
|  | ); | 
|  | goto exit; | 
|  | } | 
|  | } | 
|  |  | 
|  | hw->conv (dst, src, nread); | 
|  |  | 
|  | src = advance (src, nread << hwshift); | 
|  | dst += nread; | 
|  |  | 
|  | read_samples += nread; | 
|  | len -= nread; | 
|  | } | 
|  | } | 
|  |  | 
|  | exit: | 
|  | hw->wpos = (hw->wpos + read_samples) % hw->samples; | 
|  | return read_samples; | 
|  | } | 
|  |  | 
|  | static int alsa_read (SWVoiceIn *sw, void *buf, int size) | 
|  | { | 
|  | return audio_pcm_sw_read (sw, buf, size); | 
|  | } | 
|  |  | 
|  | static int alsa_ctl_in (HWVoiceIn *hw, int cmd, ...) | 
|  | { | 
|  | ALSAVoiceIn *alsa = (ALSAVoiceIn *) hw; | 
|  |  | 
|  | switch (cmd) { | 
|  | case VOICE_ENABLE: | 
|  | { | 
|  | va_list ap; | 
|  | int poll_mode; | 
|  |  | 
|  | va_start (ap, cmd); | 
|  | poll_mode = va_arg (ap, int); | 
|  | va_end (ap); | 
|  |  | 
|  | ldebug ("enabling voice\n"); | 
|  | if (poll_mode && alsa_poll_in (hw)) { | 
|  | poll_mode = 0; | 
|  | } | 
|  | hw->poll_mode = poll_mode; | 
|  |  | 
|  | return alsa_voice_ctl (alsa->handle, "capture", VOICE_CTL_START); | 
|  | } | 
|  |  | 
|  | case VOICE_DISABLE: | 
|  | ldebug ("disabling voice\n"); | 
|  | if (hw->poll_mode) { | 
|  | hw->poll_mode = 0; | 
|  | alsa_fini_poll (&alsa->pollhlp); | 
|  | } | 
|  | return alsa_voice_ctl (alsa->handle, "capture", VOICE_CTL_PAUSE); | 
|  | } | 
|  |  | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | static void *alsa_audio_init (void) | 
|  | { | 
|  | return &conf; | 
|  | } | 
|  |  | 
|  | static void alsa_audio_fini (void *opaque) | 
|  | { | 
|  | (void) opaque; | 
|  | } | 
|  |  | 
|  | static struct audio_option alsa_options[] = { | 
|  | { | 
|  | .name        = "DAC_SIZE_IN_USEC", | 
|  | .tag         = AUD_OPT_BOOL, | 
|  | .valp        = &conf.size_in_usec_out, | 
|  | .descr       = "DAC period/buffer size in microseconds (otherwise in frames)" | 
|  | }, | 
|  | { | 
|  | .name        = "DAC_PERIOD_SIZE", | 
|  | .tag         = AUD_OPT_INT, | 
|  | .valp        = &conf.period_size_out, | 
|  | .descr       = "DAC period size (0 to go with system default)", | 
|  | .overriddenp = &conf.period_size_out_overridden | 
|  | }, | 
|  | { | 
|  | .name        = "DAC_BUFFER_SIZE", | 
|  | .tag         = AUD_OPT_INT, | 
|  | .valp        = &conf.buffer_size_out, | 
|  | .descr       = "DAC buffer size (0 to go with system default)", | 
|  | .overriddenp = &conf.buffer_size_out_overridden | 
|  | }, | 
|  | { | 
|  | .name        = "ADC_SIZE_IN_USEC", | 
|  | .tag         = AUD_OPT_BOOL, | 
|  | .valp        = &conf.size_in_usec_in, | 
|  | .descr       = | 
|  | "ADC period/buffer size in microseconds (otherwise in frames)" | 
|  | }, | 
|  | { | 
|  | .name        = "ADC_PERIOD_SIZE", | 
|  | .tag         = AUD_OPT_INT, | 
|  | .valp        = &conf.period_size_in, | 
|  | .descr       = "ADC period size (0 to go with system default)", | 
|  | .overriddenp = &conf.period_size_in_overridden | 
|  | }, | 
|  | { | 
|  | .name        = "ADC_BUFFER_SIZE", | 
|  | .tag         = AUD_OPT_INT, | 
|  | .valp        = &conf.buffer_size_in, | 
|  | .descr       = "ADC buffer size (0 to go with system default)", | 
|  | .overriddenp = &conf.buffer_size_in_overridden | 
|  | }, | 
|  | { | 
|  | .name        = "THRESHOLD", | 
|  | .tag         = AUD_OPT_INT, | 
|  | .valp        = &conf.threshold, | 
|  | .descr       = "(undocumented)" | 
|  | }, | 
|  | { | 
|  | .name        = "DAC_DEV", | 
|  | .tag         = AUD_OPT_STR, | 
|  | .valp        = &conf.pcm_name_out, | 
|  | .descr       = "DAC device name (for instance dmix)" | 
|  | }, | 
|  | { | 
|  | .name        = "ADC_DEV", | 
|  | .tag         = AUD_OPT_STR, | 
|  | .valp        = &conf.pcm_name_in, | 
|  | .descr       = "ADC device name" | 
|  | }, | 
|  | { | 
|  | .name        = "VERBOSE", | 
|  | .tag         = AUD_OPT_BOOL, | 
|  | .valp        = &conf.verbose, | 
|  | .descr       = "Behave in a more verbose way" | 
|  | }, | 
|  | { /* End of list */ } | 
|  | }; | 
|  |  | 
|  | static struct audio_pcm_ops alsa_pcm_ops = { | 
|  | .init_out = alsa_init_out, | 
|  | .fini_out = alsa_fini_out, | 
|  | .run_out  = alsa_run_out, | 
|  | .write    = alsa_write, | 
|  | .ctl_out  = alsa_ctl_out, | 
|  |  | 
|  | .init_in  = alsa_init_in, | 
|  | .fini_in  = alsa_fini_in, | 
|  | .run_in   = alsa_run_in, | 
|  | .read     = alsa_read, | 
|  | .ctl_in   = alsa_ctl_in, | 
|  | }; | 
|  |  | 
|  | struct audio_driver alsa_audio_driver = { | 
|  | .name           = "alsa", | 
|  | .descr          = "ALSA http://www.alsa-project.org", | 
|  | .options        = alsa_options, | 
|  | .init           = alsa_audio_init, | 
|  | .fini           = alsa_audio_fini, | 
|  | .pcm_ops        = &alsa_pcm_ops, | 
|  | .can_be_default = 1, | 
|  | .max_voices_out = INT_MAX, | 
|  | .max_voices_in  = INT_MAX, | 
|  | .voice_size_out = sizeof (ALSAVoiceOut), | 
|  | .voice_size_in  = sizeof (ALSAVoiceIn) | 
|  | }; |