/* * * BlueZ - Bluetooth protocol stack for Linux * * Copyright (C) 2006-2007 Nokia Corporation * Copyright (C) 2004-2009 Marcel Holtmann * * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * */ #ifdef HAVE_CONFIG_H #include #endif #include #include #include #include #include #include #include #include #include #include #include #include "ipc.h" #include "sbc.h" #include "rtp.h" //#define ENABLE_DEBUG #define UINT_SECS_MAX (UINT_MAX / 1000000 - 1) #define MIN_PERIOD_TIME 1 #define BUFFER_SIZE 2048 #ifdef ENABLE_DEBUG #define DBG(fmt, arg...) printf("DEBUG: %s: " fmt "\n" , __FUNCTION__ , ## arg) #else #define DBG(fmt, arg...) #endif #ifndef SOL_SCO #define SOL_SCO 17 #endif #ifndef SCO_TXBUFS #define SCO_TXBUFS 0x03 #endif #ifndef SCO_RXBUFS #define SCO_RXBUFS 0x04 #endif #ifndef MIN # define MIN(x, y) ((x) < (y) ? (x) : (y)) #endif #ifndef MAX # define MAX(x, y) ((x) > (y) ? (x) : (y)) #endif #define MAX_BITPOOL 64 #define MIN_BITPOOL 2 /* adapted from glibc sys/time.h timersub() macro */ #define priv_timespecsub(a, b, result) \ do { \ (result)->tv_sec = (a)->tv_sec - (b)->tv_sec; \ (result)->tv_nsec = (a)->tv_nsec - (b)->tv_nsec; \ if ((result)->tv_nsec < 0) { \ --(result)->tv_sec; \ (result)->tv_nsec += 1000000000; \ } \ } while (0) struct bluetooth_a2dp { sbc_capabilities_t sbc_capabilities; sbc_t sbc; /* Codec data */ int sbc_initialized; /* Keep track if the encoder is initialized */ unsigned int codesize; /* SBC codesize */ int samples; /* Number of encoded samples */ uint8_t buffer[BUFFER_SIZE]; /* Codec transfer buffer */ unsigned int count; /* Codec transfer buffer counter */ int nsamples; /* Cumulative number of codec samples */ uint16_t seq_num; /* Cumulative packet sequence */ int frame_count; /* Current frames in buffer*/ }; struct bluetooth_alsa_config { char device[18]; /* Address of the remote Device */ int has_device; uint8_t transport; /* Requested transport */ int has_transport; uint16_t rate; int has_rate; uint8_t channel_mode; /* A2DP only */ int has_channel_mode; uint8_t allocation_method; /* A2DP only */ int has_allocation_method; uint8_t subbands; /* A2DP only */ int has_subbands; uint8_t block_length; /* A2DP only */ int has_block_length; uint8_t bitpool; /* A2DP only */ int has_bitpool; int autoconnect; }; struct bluetooth_data { snd_pcm_ioplug_t io; struct bluetooth_alsa_config alsa_config; /* ALSA resource file parameters */ volatile snd_pcm_sframes_t hw_ptr; int transport; /* chosen transport SCO or AD2P */ unsigned int link_mtu; /* MTU for selected transport channel */ volatile struct pollfd stream; /* Audio stream filedescriptor */ struct pollfd server; /* Audio daemon filedescriptor */ uint8_t buffer[BUFFER_SIZE]; /* Encoded transfer buffer */ unsigned int count; /* Transfer buffer counter */ struct bluetooth_a2dp a2dp; /* A2DP data */ pthread_t hw_thread; /* Makes virtual hw pointer move */ int pipefd[2]; /* Inter thread communication */ int stopped; sig_atomic_t reset; /* Request XRUN handling */ }; static int audioservice_send(int sk, const bt_audio_msg_header_t *msg); static int audioservice_expect(int sk, bt_audio_msg_header_t *outmsg, int expected_type); static int bluetooth_start(snd_pcm_ioplug_t *io) { DBG("bluetooth_start %p", io); return 0; } static int bluetooth_stop(snd_pcm_ioplug_t *io) { DBG("bluetooth_stop %p", io); return 0; } static void *playback_hw_thread(void *param) { struct bluetooth_data *data = param; unsigned int prev_periods; double period_time; struct timespec start; struct pollfd fds[2]; int poll_timeout; data->server.events = POLLIN; /* note: only errors for data->stream.events */ fds[0] = data->server; fds[1] = data->stream; prev_periods = 0; period_time = 1000000.0 * data->io.period_size / data->io.rate; if (period_time > (int) (MIN_PERIOD_TIME * 1000)) poll_timeout = (int) (period_time / 1000.0f); else poll_timeout = MIN_PERIOD_TIME; clock_gettime(CLOCK_MONOTONIC, &start); while (1) { unsigned int dtime, periods; struct timespec cur, delta; int ret; if (data->stopped) goto iter_sleep; if (data->reset) { DBG("Handle XRUN in hw-thread."); data->reset = 0; clock_gettime(CLOCK_MONOTONIC, &start); prev_periods = 0; } clock_gettime(CLOCK_MONOTONIC, &cur); priv_timespecsub(&cur, &start, &delta); dtime = delta.tv_sec * 1000000 + delta.tv_nsec / 1000; periods = 1.0 * dtime / period_time; if (periods > prev_periods) { char c = 'w'; int frags = periods - prev_periods, n; data->hw_ptr += frags * data->io.period_size; data->hw_ptr %= data->io.buffer_size; for (n = 0; n < frags; n++) { /* Notify user that hardware pointer * has moved * */ if (write(data->pipefd[1], &c, 1) < 0) pthread_testcancel(); } /* Reset point of reference to avoid too big values * that wont fit an unsigned int */ if ((unsigned int) delta.tv_sec < UINT_SECS_MAX) prev_periods = periods; else { prev_periods = 0; clock_gettime(CLOCK_MONOTONIC, &start); } } iter_sleep: /* sleep up to one period interval */ ret = poll(fds, 2, poll_timeout); if (ret < 0) { SNDERR("poll error: %s (%d)", strerror(errno), errno); if (errno != EINTR) break; } else if (ret > 0) { ret = (fds[0].revents) ? 0 : 1; SNDERR("poll fd %d revents %d", ret, fds[ret].revents); if (fds[ret].revents & (POLLERR | POLLHUP | POLLNVAL)) break; } /* Offer opportunity to be canceled by main thread */ pthread_testcancel(); } data->hw_thread = 0; pthread_exit(NULL); } static int bluetooth_playback_start(snd_pcm_ioplug_t *io) { struct bluetooth_data *data = io->private_data; int err; DBG("%p", io); data->stopped = 0; if (data->hw_thread) return 0; err = pthread_create(&data->hw_thread, 0, playback_hw_thread, data); return -err; } static int bluetooth_playback_stop(snd_pcm_ioplug_t *io) { struct bluetooth_data *data = io->private_data; DBG("%p", io); data->stopped = 1; return 0; } static snd_pcm_sframes_t bluetooth_pointer(snd_pcm_ioplug_t *io) { struct bluetooth_data *data = io->private_data; return data->hw_ptr; } static void bluetooth_exit(struct bluetooth_data *data) { struct bluetooth_a2dp *a2dp = &data->a2dp; if (data->server.fd >= 0) bt_audio_service_close(data->server.fd); if (data->stream.fd >= 0) close(data->stream.fd); if (data->hw_thread) { pthread_cancel(data->hw_thread); pthread_join(data->hw_thread, 0); } if (a2dp->sbc_initialized) sbc_finish(&a2dp->sbc); if (data->pipefd[0] > 0) close(data->pipefd[0]); if (data->pipefd[1] > 0) close(data->pipefd[1]); free(data); } static int bluetooth_close(snd_pcm_ioplug_t *io) { struct bluetooth_data *data = io->private_data; DBG("%p", io); bluetooth_exit(data); return 0; } static int bluetooth_prepare(snd_pcm_ioplug_t *io) { struct bluetooth_data *data = io->private_data; char c = 'w'; char buf[BT_SUGGESTED_BUFFER_SIZE]; struct bt_start_stream_req *req = (void *) buf; struct bt_start_stream_rsp *rsp = (void *) buf; struct bt_new_stream_ind *ind = (void *) buf; uint32_t period_count = io->buffer_size / io->period_size; int opt_name, err; struct timeval t = { 0, period_count }; DBG("Preparing with io->period_size=%lu io->buffer_size=%lu", io->period_size, io->buffer_size); data->reset = 0; /* As we're gonna receive messages on the server socket, we have to stop the hw thread that is polling on it, if any */ if (data->hw_thread) { pthread_cancel(data->hw_thread); pthread_join(data->hw_thread, 0); data->hw_thread = 0; } if (io->stream == SND_PCM_STREAM_PLAYBACK) /* If not null for playback, xmms doesn't display time * correctly */ data->hw_ptr = 0; else /* ALSA library is really picky on the fact hw_ptr is not null. * If it is, capture won't start */ data->hw_ptr = io->period_size; /* send start */ memset(req, 0, BT_SUGGESTED_BUFFER_SIZE); req->h.type = BT_REQUEST; req->h.name = BT_START_STREAM; req->h.length = sizeof(*req); err = audioservice_send(data->server.fd, &req->h); if (err < 0) return err; rsp->h.length = sizeof(*rsp); err = audioservice_expect(data->server.fd, &rsp->h, BT_START_STREAM); if (err < 0) return err; ind->h.length = sizeof(*ind); err = audioservice_expect(data->server.fd, &ind->h, BT_NEW_STREAM); if (err < 0) return err; if (data->stream.fd >= 0) close(data->stream.fd); data->stream.fd = bt_audio_service_get_data_fd(data->server.fd); if (data->stream.fd < 0) { return -errno; } if (data->transport == BT_CAPABILITIES_TRANSPORT_A2DP) { opt_name = (io->stream == SND_PCM_STREAM_PLAYBACK) ? SO_SNDTIMEO : SO_RCVTIMEO; if (setsockopt(data->stream.fd, SOL_SOCKET, opt_name, &t, sizeof(t)) < 0) return -errno; } else { opt_name = (io->stream == SND_PCM_STREAM_PLAYBACK) ? SCO_TXBUFS : SCO_RXBUFS; if (setsockopt(data->stream.fd, SOL_SCO, opt_name, &period_count, sizeof(period_count)) == 0) return 0; opt_name = (io->stream == SND_PCM_STREAM_PLAYBACK) ? SO_SNDBUF : SO_RCVBUF; if (setsockopt(data->stream.fd, SOL_SCO, opt_name, &period_count, sizeof(period_count)) == 0) return 0; /* FIXME : handle error codes */ } /* wake up any client polling at us */ err = write(data->pipefd[1], &c, 1); if (err < 0) return err; return 0; } static int bluetooth_hsp_hw_params(snd_pcm_ioplug_t *io, snd_pcm_hw_params_t *params) { struct bluetooth_data *data = io->private_data; char buf[BT_SUGGESTED_BUFFER_SIZE]; struct bt_set_configuration_req *req = (void *) buf; struct bt_set_configuration_rsp *rsp = (void *) buf; int err; DBG("Preparing with io->period_size=%lu io->buffer_size=%lu", io->period_size, io->buffer_size); memset(req, 0, BT_SUGGESTED_BUFFER_SIZE); req->h.type = BT_REQUEST; req->h.name = BT_SET_CONFIGURATION; req->h.length = sizeof(*req); strncpy(req->device, data->alsa_config.device, 18); req->codec.transport = BT_CAPABILITIES_TRANSPORT_SCO; req->codec.length = sizeof(pcm_capabilities_t); req->access_mode = (io->stream == SND_PCM_STREAM_PLAYBACK ? BT_CAPABILITIES_ACCESS_MODE_WRITE : BT_CAPABILITIES_ACCESS_MODE_READ); req->h.length += req->codec.length - sizeof(req->codec); err = audioservice_send(data->server.fd, &req->h); if (err < 0) return err; rsp->h.length = sizeof(*rsp); err = audioservice_expect(data->server.fd, &rsp->h, BT_SET_CONFIGURATION); if (err < 0) return err; data->transport = rsp->transport; data->link_mtu = rsp->link_mtu; return 0; } static uint8_t default_bitpool(uint8_t freq, uint8_t mode) { switch (freq) { case BT_SBC_SAMPLING_FREQ_16000: case BT_SBC_SAMPLING_FREQ_32000: return 53; case BT_SBC_SAMPLING_FREQ_44100: switch (mode) { case BT_A2DP_CHANNEL_MODE_MONO: case BT_A2DP_CHANNEL_MODE_DUAL_CHANNEL: return 31; case BT_A2DP_CHANNEL_MODE_STEREO: case BT_A2DP_CHANNEL_MODE_JOINT_STEREO: return 53; default: DBG("Invalid channel mode %u", mode); return 53; } case BT_SBC_SAMPLING_FREQ_48000: switch (mode) { case BT_A2DP_CHANNEL_MODE_MONO: case BT_A2DP_CHANNEL_MODE_DUAL_CHANNEL: return 29; case BT_A2DP_CHANNEL_MODE_STEREO: case BT_A2DP_CHANNEL_MODE_JOINT_STEREO: return 51; default: DBG("Invalid channel mode %u", mode); return 51; } default: DBG("Invalid sampling freq %u", freq); return 53; } } static int bluetooth_a2dp_init(struct bluetooth_data *data, snd_pcm_hw_params_t *params) { struct bluetooth_alsa_config *cfg = &data->alsa_config; sbc_capabilities_t *cap = &data->a2dp.sbc_capabilities; unsigned int max_bitpool, min_bitpool, rate, channels; int dir; snd_pcm_hw_params_get_rate(params, &rate, &dir); snd_pcm_hw_params_get_channels(params, &channels); switch (rate) { case 48000: cap->frequency = BT_SBC_SAMPLING_FREQ_48000; break; case 44100: cap->frequency = BT_SBC_SAMPLING_FREQ_44100; break; case 32000: cap->frequency = BT_SBC_SAMPLING_FREQ_32000; break; case 16000: cap->frequency = BT_SBC_SAMPLING_FREQ_16000; break; default: DBG("Rate %d not supported", rate); return -1; } if (cfg->has_channel_mode) cap->channel_mode = cfg->channel_mode; else if (channels == 2) { if (cap->channel_mode & BT_A2DP_CHANNEL_MODE_JOINT_STEREO) cap->channel_mode = BT_A2DP_CHANNEL_MODE_JOINT_STEREO; else if (cap->channel_mode & BT_A2DP_CHANNEL_MODE_STEREO) cap->channel_mode = BT_A2DP_CHANNEL_MODE_STEREO; else if (cap->channel_mode & BT_A2DP_CHANNEL_MODE_DUAL_CHANNEL) cap->channel_mode = BT_A2DP_CHANNEL_MODE_DUAL_CHANNEL; } else { if (cap->channel_mode & BT_A2DP_CHANNEL_MODE_MONO) cap->channel_mode = BT_A2DP_CHANNEL_MODE_MONO; } if (!cap->channel_mode) { DBG("No supported channel modes"); return -1; } if (cfg->has_block_length) cap->block_length = cfg->block_length; else if (cap->block_length & BT_A2DP_BLOCK_LENGTH_16) cap->block_length = BT_A2DP_BLOCK_LENGTH_16; else if (cap->block_length & BT_A2DP_BLOCK_LENGTH_12) cap->block_length = BT_A2DP_BLOCK_LENGTH_12; else if (cap->block_length & BT_A2DP_BLOCK_LENGTH_8) cap->block_length = BT_A2DP_BLOCK_LENGTH_8; else if (cap->block_length & BT_A2DP_BLOCK_LENGTH_4) cap->block_length = BT_A2DP_BLOCK_LENGTH_4; else { DBG("No supported block lengths"); return -1; } if (cfg->has_subbands) cap->subbands = cfg->subbands; if (cap->subbands & BT_A2DP_SUBBANDS_8) cap->subbands = BT_A2DP_SUBBANDS_8; else if (cap->subbands & BT_A2DP_SUBBANDS_4) cap->subbands = BT_A2DP_SUBBANDS_4; else { DBG("No supported subbands"); return -1; } if (cfg->has_allocation_method) cap->allocation_method = cfg->allocation_method; if (cap->allocation_method & BT_A2DP_ALLOCATION_LOUDNESS) cap->allocation_method = BT_A2DP_ALLOCATION_LOUDNESS; else if (cap->allocation_method & BT_A2DP_ALLOCATION_SNR) cap->allocation_method = BT_A2DP_ALLOCATION_SNR; if (cfg->has_bitpool) min_bitpool = max_bitpool = cfg->bitpool; else { min_bitpool = MAX(MIN_BITPOOL, cap->min_bitpool); max_bitpool = MIN(default_bitpool(cap->frequency, cap->channel_mode), cap->max_bitpool); } cap->min_bitpool = min_bitpool; cap->max_bitpool = max_bitpool; return 0; } static void bluetooth_a2dp_setup(struct bluetooth_a2dp *a2dp) { sbc_capabilities_t active_capabilities = a2dp->sbc_capabilities; if (a2dp->sbc_initialized) sbc_reinit(&a2dp->sbc, 0); else sbc_init(&a2dp->sbc, 0); a2dp->sbc_initialized = 1; if (active_capabilities.frequency & BT_SBC_SAMPLING_FREQ_16000) a2dp->sbc.frequency = SBC_FREQ_16000; if (active_capabilities.frequency & BT_SBC_SAMPLING_FREQ_32000) a2dp->sbc.frequency = SBC_FREQ_32000; if (active_capabilities.frequency & BT_SBC_SAMPLING_FREQ_44100) a2dp->sbc.frequency = SBC_FREQ_44100; if (active_capabilities.frequency & BT_SBC_SAMPLING_FREQ_48000) a2dp->sbc.frequency = SBC_FREQ_48000; if (active_capabilities.channel_mode & BT_A2DP_CHANNEL_MODE_MONO) a2dp->sbc.mode = SBC_MODE_MONO; if (active_capabilities.channel_mode & BT_A2DP_CHANNEL_MODE_DUAL_CHANNEL) a2dp->sbc.mode = SBC_MODE_DUAL_CHANNEL; if (active_capabilities.channel_mode & BT_A2DP_CHANNEL_MODE_STEREO) a2dp->sbc.mode = SBC_MODE_STEREO; if (active_capabilities.channel_mode & BT_A2DP_CHANNEL_MODE_JOINT_STEREO) a2dp->sbc.mode = SBC_MODE_JOINT_STEREO; a2dp->sbc.allocation = active_capabilities.allocation_method == BT_A2DP_ALLOCATION_SNR ? SBC_AM_SNR : SBC_AM_LOUDNESS; switch (active_capabilities.subbands) { case BT_A2DP_SUBBANDS_4: a2dp->sbc.subbands = SBC_SB_4; break; case BT_A2DP_SUBBANDS_8: a2dp->sbc.subbands = SBC_SB_8; break; } switch (active_capabilities.block_length) { case BT_A2DP_BLOCK_LENGTH_4: a2dp->sbc.blocks = SBC_BLK_4; break; case BT_A2DP_BLOCK_LENGTH_8: a2dp->sbc.blocks = SBC_BLK_8; break; case BT_A2DP_BLOCK_LENGTH_12: a2dp->sbc.blocks = SBC_BLK_12; break; case BT_A2DP_BLOCK_LENGTH_16: a2dp->sbc.blocks = SBC_BLK_16; break; } a2dp->sbc.bitpool = active_capabilities.max_bitpool; a2dp->codesize = sbc_get_codesize(&a2dp->sbc); a2dp->count = sizeof(struct rtp_header) + sizeof(struct rtp_payload); } static int bluetooth_a2dp_hw_params(snd_pcm_ioplug_t *io, snd_pcm_hw_params_t *params) { struct bluetooth_data *data = io->private_data; struct bluetooth_a2dp *a2dp = &data->a2dp; char buf[BT_SUGGESTED_BUFFER_SIZE]; struct bt_set_configuration_req *req = (void *) buf; struct bt_set_configuration_rsp *rsp = (void *) buf; int err; DBG("Preparing with io->period_size=%lu io->buffer_size=%lu", io->period_size, io->buffer_size); err = bluetooth_a2dp_init(data, params); if (err < 0) return err; memset(req, 0, BT_SUGGESTED_BUFFER_SIZE); req->h.type = BT_REQUEST; req->h.name = BT_SET_CONFIGURATION; req->h.length = sizeof(*req); strncpy(req->device, data->alsa_config.device, 18); memcpy(&req->codec, &a2dp->sbc_capabilities, sizeof(a2dp->sbc_capabilities)); req->codec.transport = BT_CAPABILITIES_TRANSPORT_A2DP; req->codec.length = sizeof(a2dp->sbc_capabilities); req->access_mode = (io->stream == SND_PCM_STREAM_PLAYBACK ? BT_CAPABILITIES_ACCESS_MODE_WRITE : BT_CAPABILITIES_ACCESS_MODE_READ); req->h.length += req->codec.length - sizeof(req->codec); err = audioservice_send(data->server.fd, &req->h); if (err < 0) return err; rsp->h.length = sizeof(*rsp); err = audioservice_expect(data->server.fd, &rsp->h, BT_SET_CONFIGURATION); if (err < 0) return err; data->transport = rsp->transport; data->link_mtu = rsp->link_mtu; /* Setup SBC encoder now we agree on parameters */ bluetooth_a2dp_setup(a2dp); DBG("\tallocation=%u\n\tsubbands=%u\n\tblocks=%u\n\tbitpool=%u\n", a2dp->sbc.allocation, a2dp->sbc.subbands, a2dp->sbc.blocks, a2dp->sbc.bitpool); return 0; } static int bluetooth_poll_descriptors(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int space) { struct bluetooth_data *data = io->private_data; assert(io); if (space < 1) return 0; pfd[0].fd = data->stream.fd; pfd[0].events = POLLIN; pfd[0].revents = 0; return 1; } static int bluetooth_poll_revents(snd_pcm_ioplug_t *io ATTRIBUTE_UNUSED, struct pollfd *pfds, unsigned int nfds, unsigned short *revents) { assert(pfds && nfds == 1 && revents); *revents = pfds[0].revents; return 0; } static int bluetooth_playback_poll_descriptors_count(snd_pcm_ioplug_t *io) { return 2; } static int bluetooth_playback_poll_descriptors(snd_pcm_ioplug_t *io, struct pollfd *pfd, unsigned int space) { struct bluetooth_data *data = io->private_data; DBG(""); assert(data->pipefd[0] >= 0); if (space < 2) return 0; pfd[0].fd = data->pipefd[0]; pfd[0].events = POLLIN; pfd[0].revents = 0; pfd[1].fd = data->stream.fd; pfd[1].events = POLLERR | POLLHUP | POLLNVAL; pfd[1].revents = 0; return 2; } static int bluetooth_playback_poll_revents(snd_pcm_ioplug_t *io, struct pollfd *pfds, unsigned int nfds, unsigned short *revents) { static char buf[1]; int ret; DBG(""); assert(pfds); assert(nfds == 2); assert(revents); assert(pfds[0].fd >= 0); assert(pfds[1].fd >= 0); if (io->state != SND_PCM_STATE_PREPARED) ret = read(pfds[0].fd, buf, 1); if (pfds[1].revents & (POLLERR | POLLHUP | POLLNVAL)) io->state = SND_PCM_STATE_DISCONNECTED; *revents = (pfds[0].revents & POLLIN) ? POLLOUT : 0; return 0; } static snd_pcm_sframes_t bluetooth_hsp_read(snd_pcm_ioplug_t *io, const snd_pcm_channel_area_t *areas, snd_pcm_uframes_t offset, snd_pcm_uframes_t size) { struct bluetooth_data *data = io->private_data; snd_pcm_uframes_t frames_to_write, ret; unsigned char *buff; unsigned int frame_size = 0; int nrecv; DBG("areas->step=%u areas->first=%u offset=%lu size=%lu io->nonblock=%u", areas->step, areas->first, offset, size, io->nonblock); frame_size = areas->step / 8; if (data->count > 0) goto proceed; nrecv = recv(data->stream.fd, data->buffer, data->link_mtu, io->nonblock ? MSG_DONTWAIT : 0); if (nrecv < 0) { ret = (errno == EPIPE) ? -EIO : -errno; goto done; } if ((unsigned int) nrecv != data->link_mtu) { ret = -EIO; SNDERR(strerror(-ret)); goto done; } /* Increment hardware transmition pointer */ data->hw_ptr = (data->hw_ptr + data->link_mtu / frame_size) % io->buffer_size; proceed: buff = (unsigned char *) areas->addr + (areas->first + areas->step * offset) / 8; if ((data->count + size * frame_size) <= data->link_mtu) frames_to_write = size; else frames_to_write = (data->link_mtu - data->count) / frame_size; memcpy(buff, data->buffer + data->count, frame_size * frames_to_write); data->count += (frame_size * frames_to_write); data->count %= data->link_mtu; /* Return written frames count */ ret = frames_to_write; done: DBG("returning %lu", ret); return ret; } static snd_pcm_sframes_t bluetooth_hsp_write(snd_pcm_ioplug_t *io, const snd_pcm_channel_area_t *areas, snd_pcm_uframes_t offset, snd_pcm_uframes_t size) { struct bluetooth_data *data = io->private_data; snd_pcm_sframes_t ret = 0; snd_pcm_uframes_t frames_to_read; uint8_t *buff; int rsend, frame_size; DBG("areas->step=%u areas->first=%u offset=%lu, size=%lu io->nonblock=%u", areas->step, areas->first, offset, size, io->nonblock); if (io->hw_ptr > io->appl_ptr) { ret = bluetooth_playback_stop(io); if (ret == 0) ret = -EPIPE; goto done; } frame_size = areas->step / 8; if ((data->count + size * frame_size) <= data->link_mtu) frames_to_read = size; else frames_to_read = (data->link_mtu - data->count) / frame_size; DBG("count=%d frames_to_read=%lu", data->count, frames_to_read); /* Ready for more data */ buff = (uint8_t *) areas->addr + (areas->first + areas->step * offset) / 8; memcpy(data->buffer + data->count, buff, frame_size * frames_to_read); /* Remember we have some frames in the pipe now */ data->count += frames_to_read * frame_size; if (data->count != data->link_mtu) { ret = frames_to_read; goto done; } rsend = send(data->stream.fd, data->buffer, data->link_mtu, io->nonblock ? MSG_DONTWAIT : 0); if (rsend > 0) { /* Reset count pointer */ data->count = 0; ret = frames_to_read; } else if (rsend < 0) ret = (errno == EPIPE) ? -EIO : -errno; else ret = -EIO; done: DBG("returning %ld", ret); return ret; } static snd_pcm_sframes_t bluetooth_a2dp_read(snd_pcm_ioplug_t *io, const snd_pcm_channel_area_t *areas, snd_pcm_uframes_t offset, snd_pcm_uframes_t size) { snd_pcm_uframes_t ret = 0; return ret; } static int avdtp_write(struct bluetooth_data *data) { int ret = 0; struct rtp_header *header; struct rtp_payload *payload; struct bluetooth_a2dp *a2dp = &data->a2dp; header = (void *) a2dp->buffer; payload = (void *) (a2dp->buffer + sizeof(*header)); memset(a2dp->buffer, 0, sizeof(*header) + sizeof(*payload)); payload->frame_count = a2dp->frame_count; header->v = 2; header->pt = 1; header->sequence_number = htons(a2dp->seq_num); header->timestamp = htonl(a2dp->nsamples); header->ssrc = htonl(1); ret = send(data->stream.fd, a2dp->buffer, a2dp->count, MSG_DONTWAIT); if (ret < 0) { DBG("send returned %d errno %s.", ret, strerror(errno)); ret = -errno; } /* Reset buffer of data to send */ a2dp->count = sizeof(struct rtp_header) + sizeof(struct rtp_payload); a2dp->frame_count = 0; a2dp->samples = 0; a2dp->seq_num++; return ret; } static snd_pcm_sframes_t bluetooth_a2dp_write(snd_pcm_ioplug_t *io, const snd_pcm_channel_area_t *areas, snd_pcm_uframes_t offset, snd_pcm_uframes_t size) { struct bluetooth_data *data = io->private_data; struct bluetooth_a2dp *a2dp = &data->a2dp; snd_pcm_sframes_t ret = 0; unsigned int bytes_left; int frame_size, encoded; size_t written; uint8_t *buff; DBG("areas->step=%u areas->first=%u offset=%lu size=%lu", areas->step, areas->first, offset, size); DBG("hw_ptr=%lu appl_ptr=%lu diff=%lu", io->hw_ptr, io->appl_ptr, io->appl_ptr - io->hw_ptr); /* Calutate starting pointers */ frame_size = areas->step / 8; bytes_left = size * frame_size; buff = (uint8_t *) areas->addr + (areas->first + areas->step * (offset)) / 8; /* Check for underrun */ if (io->hw_ptr > io->appl_ptr) { ret = bluetooth_playback_stop(io); if (ret == 0) ret = -EPIPE; data->reset = 1; return ret; } /* Check if we should autostart */ if (io->state == SND_PCM_STATE_PREPARED) { snd_pcm_sw_params_t *swparams; snd_pcm_uframes_t threshold; snd_pcm_sw_params_malloc(&swparams); if (!snd_pcm_sw_params_current(io->pcm, swparams) && !snd_pcm_sw_params_get_start_threshold(swparams, &threshold)) { if (io->appl_ptr >= threshold) { ret = snd_pcm_start(io->pcm); if (ret != 0) return ret; } } snd_pcm_sw_params_free(swparams); } /* Check if we have any left over data from the last write */ if (data->count > 0 && (bytes_left - data->count) >= a2dp->codesize) { int additional_bytes_needed = a2dp->codesize - data->count; memcpy(data->buffer + data->count, buff, additional_bytes_needed); /* Enough data to encode (sbc wants 1k blocks) */ encoded = sbc_encode(&a2dp->sbc, data->buffer, a2dp->codesize, a2dp->buffer + a2dp->count, sizeof(a2dp->buffer) - a2dp->count, &written); if (encoded <= 0) { DBG("Encoding error %d", encoded); goto done; } /* Increment a2dp buffers */ a2dp->count += written; a2dp->frame_count++; a2dp->samples += encoded / frame_size; a2dp->nsamples += encoded / frame_size; /* No space left for another frame then send */ if (a2dp->count + written >= data->link_mtu) { avdtp_write(data); DBG("sending packet %d, count %d, link_mtu %u", a2dp->seq_num, a2dp->count, data->link_mtu); } /* Increment up buff pointer to take into account * the data processed */ buff += additional_bytes_needed; bytes_left -= additional_bytes_needed; /* Since data has been process mark it as zero */ data->count = 0; } /* Process this buffer in full chunks */ while (bytes_left >= a2dp->codesize) { /* Enough data to encode (sbc wants 1k blocks) */ encoded = sbc_encode(&a2dp->sbc, buff, a2dp->codesize, a2dp->buffer + a2dp->count, sizeof(a2dp->buffer) - a2dp->count, &written); if (encoded <= 0) { DBG("Encoding error %d", encoded); goto done; } /* Increment up buff pointer to take into account * the data processed */ buff += a2dp->codesize; bytes_left -= a2dp->codesize; /* Increment a2dp buffers */ a2dp->count += written; a2dp->frame_count++; a2dp->samples += encoded / frame_size; a2dp->nsamples += encoded / frame_size; /* No space left for another frame then send */ if (a2dp->count + written >= data->link_mtu) { avdtp_write(data); DBG("sending packet %d, count %d, link_mtu %u", a2dp->seq_num, a2dp->count, data->link_mtu); } } /* Copy the extra to our temp buffer for the next write */ if (bytes_left > 0) { memcpy(data->buffer + data->count, buff, bytes_left); data->count += bytes_left; bytes_left = 0; } done: DBG("returning %ld", size - bytes_left / frame_size); return size - bytes_left / frame_size; } static int bluetooth_playback_delay(snd_pcm_ioplug_t *io, snd_pcm_sframes_t *delayp) { DBG(""); /* This updates io->hw_ptr value using pointer() function */ snd_pcm_hwsync(io->pcm); *delayp = io->appl_ptr - io->hw_ptr; if ((io->state == SND_PCM_STATE_RUNNING) && (*delayp < 0)) { io->callback->stop(io); io->state = SND_PCM_STATE_XRUN; *delayp = 0; } /* This should never fail, ALSA API is really not prepared to handle a non zero return value */ return 0; } static snd_pcm_ioplug_callback_t bluetooth_hsp_playback = { .start = bluetooth_playback_start, .stop = bluetooth_playback_stop, .pointer = bluetooth_pointer, .close = bluetooth_close, .hw_params = bluetooth_hsp_hw_params, .prepare = bluetooth_prepare, .transfer = bluetooth_hsp_write, .poll_descriptors_count = bluetooth_playback_poll_descriptors_count, .poll_descriptors = bluetooth_playback_poll_descriptors, .poll_revents = bluetooth_playback_poll_revents, .delay = bluetooth_playback_delay, }; static snd_pcm_ioplug_callback_t bluetooth_hsp_capture = { .start = bluetooth_start, .stop = bluetooth_stop, .pointer = bluetooth_pointer, .close = bluetooth_close, .hw_params = bluetooth_hsp_hw_params, .prepare = bluetooth_prepare, .transfer = bluetooth_hsp_read, .poll_descriptors = bluetooth_poll_descriptors, .poll_revents = bluetooth_poll_revents, }; static snd_pcm_ioplug_callback_t bluetooth_a2dp_playback = { .start = bluetooth_playback_start, .stop = bluetooth_playback_stop, .pointer = bluetooth_pointer, .close = bluetooth_close, .hw_params = bluetooth_a2dp_hw_params, .prepare = bluetooth_prepare, .transfer = bluetooth_a2dp_write, .poll_descriptors_count = bluetooth_playback_poll_descriptors_count, .poll_descriptors = bluetooth_playback_poll_descriptors, .poll_revents = bluetooth_playback_poll_revents, .delay = bluetooth_playback_delay, }; static snd_pcm_ioplug_callback_t bluetooth_a2dp_capture = { .start = bluetooth_start, .stop = bluetooth_stop, .pointer = bluetooth_pointer, .close = bluetooth_close, .hw_params = bluetooth_a2dp_hw_params, .prepare = bluetooth_prepare, .transfer = bluetooth_a2dp_read, .poll_descriptors = bluetooth_poll_descriptors, .poll_revents = bluetooth_poll_revents, }; #define ARRAY_NELEMS(a) (sizeof((a)) / sizeof((a)[0])) static int bluetooth_hsp_hw_constraint(snd_pcm_ioplug_t *io) { struct bluetooth_data *data = io->private_data; snd_pcm_access_t access_list[] = { SND_PCM_ACCESS_RW_INTERLEAVED, /* Mmap access is really useless fo this driver, but we * support it because some pieces of software out there * insist on using it */ SND_PCM_ACCESS_MMAP_INTERLEAVED }; unsigned int format_list[] = { SND_PCM_FORMAT_S16 }; int err; /* access type */ err = snd_pcm_ioplug_set_param_list(io, SND_PCM_IOPLUG_HW_ACCESS, ARRAY_NELEMS(access_list), access_list); if (err < 0) return err; /* supported formats */ err = snd_pcm_ioplug_set_param_list(io, SND_PCM_IOPLUG_HW_FORMAT, ARRAY_NELEMS(format_list), format_list); if (err < 0) return err; /* supported channels */ err = snd_pcm_ioplug_set_param_minmax(io, SND_PCM_IOPLUG_HW_CHANNELS, 1, 1); if (err < 0) return err; /* supported rate */ err = snd_pcm_ioplug_set_param_minmax(io, SND_PCM_IOPLUG_HW_RATE, 8000, 8000); if (err < 0) return err; /* supported block size */ err = snd_pcm_ioplug_set_param_minmax(io, SND_PCM_IOPLUG_HW_PERIOD_BYTES, data->link_mtu, data->link_mtu); if (err < 0) return err; err = snd_pcm_ioplug_set_param_minmax(io, SND_PCM_IOPLUG_HW_PERIODS, 2, 200); if (err < 0) return err; return 0; } static int bluetooth_a2dp_hw_constraint(snd_pcm_ioplug_t *io) { struct bluetooth_data *data = io->private_data; struct bluetooth_a2dp *a2dp = &data->a2dp; struct bluetooth_alsa_config *cfg = &data->alsa_config; snd_pcm_access_t access_list[] = { SND_PCM_ACCESS_RW_INTERLEAVED, /* Mmap access is really useless fo this driver, but we * support it because some pieces of software out there * insist on using it */ SND_PCM_ACCESS_MMAP_INTERLEAVED }; unsigned int format_list[] = { SND_PCM_FORMAT_S16 }; unsigned int rate_list[4]; unsigned int rate_count; int err, min_channels, max_channels; unsigned int period_list[] = { 2048, 4096, /* e.g. 23.2msec/period (stereo 16bit at 44.1kHz) */ 8192 }; /* access type */ err = snd_pcm_ioplug_set_param_list(io, SND_PCM_IOPLUG_HW_ACCESS, ARRAY_NELEMS(access_list), access_list); if (err < 0) return err; /* supported formats */ err = snd_pcm_ioplug_set_param_list(io, SND_PCM_IOPLUG_HW_FORMAT, ARRAY_NELEMS(format_list), format_list); if (err < 0) return err; /* supported channels */ if (cfg->has_channel_mode) a2dp->sbc_capabilities.channel_mode = cfg->channel_mode; if (a2dp->sbc_capabilities.channel_mode & BT_A2DP_CHANNEL_MODE_MONO) min_channels = 1; else min_channels = 2; if (a2dp->sbc_capabilities.channel_mode & (~BT_A2DP_CHANNEL_MODE_MONO)) max_channels = 2; else max_channels = 1; err = snd_pcm_ioplug_set_param_minmax(io, SND_PCM_IOPLUG_HW_CHANNELS, min_channels, max_channels); if (err < 0) return err; /* supported buffer sizes * (can be used as 3*8192, 6*4096, 12*2048, ...) */ err = snd_pcm_ioplug_set_param_minmax(io, SND_PCM_IOPLUG_HW_BUFFER_BYTES, 8192*3, 8192*3); if (err < 0) return err; /* supported block sizes: */ err = snd_pcm_ioplug_set_param_list(io, SND_PCM_IOPLUG_HW_PERIOD_BYTES, ARRAY_NELEMS(period_list), period_list); if (err < 0) return err; /* supported rates */ rate_count = 0; if (cfg->has_rate) { rate_list[rate_count] = cfg->rate; rate_count++; } else { if (a2dp->sbc_capabilities.frequency & BT_SBC_SAMPLING_FREQ_16000) { rate_list[rate_count] = 16000; rate_count++; } if (a2dp->sbc_capabilities.frequency & BT_SBC_SAMPLING_FREQ_32000) { rate_list[rate_count] = 32000; rate_count++; } if (a2dp->sbc_capabilities.frequency & BT_SBC_SAMPLING_FREQ_44100) { rate_list[rate_count] = 44100; rate_count++; } if (a2dp->sbc_capabilities.frequency & BT_SBC_SAMPLING_FREQ_48000) { rate_list[rate_count] = 48000; rate_count++; } } err = snd_pcm_ioplug_set_param_list(io, SND_PCM_IOPLUG_HW_RATE, rate_count, rate_list); if (err < 0) return err; return 0; } static int bluetooth_parse_config(snd_config_t *conf, struct bluetooth_alsa_config *bt_config) { snd_config_iterator_t i, next; memset(bt_config, 0, sizeof(struct bluetooth_alsa_config)); /* Set defaults */ bt_config->autoconnect = 1; snd_config_for_each(i, next, conf) { snd_config_t *n = snd_config_iterator_entry(i); const char *id, *value; if (snd_config_get_id(n, &id) < 0) continue; if (strcmp(id, "comment") == 0 || strcmp(id, "type") == 0) continue; if (strcmp(id, "autoconnect") == 0) { int b; b = snd_config_get_bool(n); if (b < 0) { SNDERR("Invalid type for %s", id); return -EINVAL; } bt_config->autoconnect = b; continue; } if (strcmp(id, "device") == 0 || strcmp(id, "bdaddr") == 0) { if (snd_config_get_string(n, &value) < 0) { SNDERR("Invalid type for %s", id); return -EINVAL; } bt_config->has_device = 1; strncpy(bt_config->device, value, 18); continue; } if (strcmp(id, "profile") == 0) { if (snd_config_get_string(n, &value) < 0) { SNDERR("Invalid type for %s", id); return -EINVAL; } if (strcmp(value, "auto") == 0) { bt_config->transport = BT_CAPABILITIES_TRANSPORT_ANY; bt_config->has_transport = 1; } else if (strcmp(value, "voice") == 0 || strcmp(value, "hfp") == 0) { bt_config->transport = BT_CAPABILITIES_TRANSPORT_SCO; bt_config->has_transport = 1; } else if (strcmp(value, "hifi") == 0 || strcmp(value, "a2dp") == 0) { bt_config->transport = BT_CAPABILITIES_TRANSPORT_A2DP; bt_config->has_transport = 1; } continue; } if (strcmp(id, "rate") == 0) { if (snd_config_get_string(n, &value) < 0) { SNDERR("Invalid type for %s", id); return -EINVAL; } bt_config->rate = atoi(value); bt_config->has_rate = 1; continue; } if (strcmp(id, "mode") == 0) { if (snd_config_get_string(n, &value) < 0) { SNDERR("Invalid type for %s", id); return -EINVAL; } if (strcmp(value, "mono") == 0) { bt_config->channel_mode = BT_A2DP_CHANNEL_MODE_MONO; bt_config->has_channel_mode = 1; } else if (strcmp(value, "dual") == 0) { bt_config->channel_mode = BT_A2DP_CHANNEL_MODE_DUAL_CHANNEL; bt_config->has_channel_mode = 1; } else if (strcmp(value, "stereo") == 0) { bt_config->channel_mode = BT_A2DP_CHANNEL_MODE_STEREO; bt_config->has_channel_mode = 1; } else if (strcmp(value, "joint") == 0) { bt_config->channel_mode = BT_A2DP_CHANNEL_MODE_JOINT_STEREO; bt_config->has_channel_mode = 1; } continue; } if (strcmp(id, "allocation") == 0) { if (snd_config_get_string(n, &value) < 0) { SNDERR("Invalid type for %s", id); return -EINVAL; } if (strcmp(value, "loudness") == 0) { bt_config->allocation_method = BT_A2DP_ALLOCATION_LOUDNESS; bt_config->has_allocation_method = 1; } else if (strcmp(value, "snr") == 0) { bt_config->allocation_method = BT_A2DP_ALLOCATION_SNR; bt_config->has_allocation_method = 1; } continue; } if (strcmp(id, "subbands") == 0) { if (snd_config_get_string(n, &value) < 0) { SNDERR("Invalid type for %s", id); return -EINVAL; } bt_config->subbands = atoi(value); bt_config->has_subbands = 1; continue; } if (strcmp(id, "blocks") == 0) { if (snd_config_get_string(n, &value) < 0) { SNDERR("Invalid type for %s", id); return -EINVAL; } bt_config->block_length = atoi(value); bt_config->has_block_length = 1; continue; } if (strcmp(id, "bitpool") == 0) { if (snd_config_get_string(n, &value) < 0) { SNDERR("Invalid type for %s", id); return -EINVAL; } bt_config->bitpool = atoi(value); bt_config->has_bitpool = 1; continue; } SNDERR("Unknown field %s", id); return -EINVAL; } return 0; } static int audioservice_send(int sk, const bt_audio_msg_header_t *msg) { int err; uint16_t length; length = msg->length ? msg->length : BT_SUGGESTED_BUFFER_SIZE; DBG("sending %s:%s", bt_audio_strtype(msg->type), bt_audio_strname(msg->name)); if (send(sk, msg, length, 0) > 0) err = 0; else { err = -errno; SNDERR("Error sending data to audio service: %s(%d)", strerror(errno), errno); } return err; } static int audioservice_recv(int sk, bt_audio_msg_header_t *inmsg) { int err; ssize_t ret; const char *type, *name; uint16_t length; length = inmsg->length ? inmsg->length : BT_SUGGESTED_BUFFER_SIZE; DBG("trying to receive msg from audio service..."); ret = recv(sk, inmsg, length, 0); if (ret < 0) { err = -errno; SNDERR("Error receiving IPC data from bluetoothd: %s (%d)", strerror(errno), errno); } else if ((size_t) ret < sizeof(bt_audio_msg_header_t)) { SNDERR("Too short (%d bytes) IPC packet from bluetoothd", ret); err = -EINVAL; } else { type = bt_audio_strtype(inmsg->type); name = bt_audio_strname(inmsg->name); if (type && name) { DBG("Received %s - %s", type, name); err = 0; } else { err = -EINVAL; SNDERR("Bogus message type %d - name %d" " received from audio service", inmsg->type, inmsg->name); } } return err; } static int audioservice_expect(int sk, bt_audio_msg_header_t *rsp, int expected_name) { bt_audio_error_t *error; int err = audioservice_recv(sk, rsp); if (err != 0) return err; if (rsp->name != expected_name) { err = -EINVAL; SNDERR("Bogus message %s received while %s was expected", bt_audio_strname(rsp->name), bt_audio_strname(expected_name)); } if (rsp->type == BT_ERROR) { error = (void *) rsp; SNDERR("%s failed : %s(%d)", bt_audio_strname(rsp->name), strerror(error->posix_errno), error->posix_errno); return -error->posix_errno; } return err; } static int bluetooth_parse_capabilities(struct bluetooth_data *data, struct bt_get_capabilities_rsp *rsp) { int bytes_left = rsp->h.length - sizeof(*rsp); codec_capabilities_t *codec = (void *) rsp->data; data->transport = codec->transport; if (codec->transport != BT_CAPABILITIES_TRANSPORT_A2DP) return 0; while (bytes_left > 0) { if (codec->type == BT_A2DP_CODEC_SBC) break; bytes_left -= codec->length; codec = (void *) codec + codec->length; } if (bytes_left <= 0 || codec->length != sizeof(data->a2dp.sbc_capabilities)) return -EINVAL; memcpy(&data->a2dp.sbc_capabilities, codec, codec->length); return 0; } static int bluetooth_init(struct bluetooth_data *data, snd_pcm_stream_t stream, snd_config_t *conf) { int sk, err; struct bluetooth_alsa_config *alsa_conf = &data->alsa_config; char buf[BT_SUGGESTED_BUFFER_SIZE]; struct bt_get_capabilities_req *req = (void *) buf; struct bt_get_capabilities_rsp *rsp = (void *) buf; memset(data, 0, sizeof(struct bluetooth_data)); err = bluetooth_parse_config(conf, alsa_conf); if (err < 0) return err; data->server.fd = -1; data->stream.fd = -1; sk = bt_audio_service_open(); if (sk <= 0) { err = -errno; goto failed; } data->server.fd = sk; data->server.events = POLLIN; data->pipefd[0] = -1; data->pipefd[1] = -1; if (pipe(data->pipefd) < 0) { err = -errno; goto failed; } if (fcntl(data->pipefd[0], F_SETFL, O_NONBLOCK) < 0) { err = -errno; goto failed; } if (fcntl(data->pipefd[1], F_SETFL, O_NONBLOCK) < 0) { err = -errno; goto failed; } memset(req, 0, BT_SUGGESTED_BUFFER_SIZE); req->h.type = BT_REQUEST; req->h.name = BT_GET_CAPABILITIES; req->h.length = sizeof(*req); if (alsa_conf->autoconnect) req->flags |= BT_FLAG_AUTOCONNECT; strncpy(req->device, alsa_conf->device, 18); if (alsa_conf->has_transport) req->transport = alsa_conf->transport; else req->transport = BT_CAPABILITIES_TRANSPORT_ANY; err = audioservice_send(data->server.fd, &req->h); if (err < 0) goto failed; rsp->h.length = 0; err = audioservice_expect(data->server.fd, &rsp->h, BT_GET_CAPABILITIES); if (err < 0) goto failed; bluetooth_parse_capabilities(data, rsp); return 0; failed: if (sk >= 0) bt_audio_service_close(sk); return err; } SND_PCM_PLUGIN_DEFINE_FUNC(bluetooth); SND_PCM_PLUGIN_DEFINE_FUNC(bluetooth) { struct bluetooth_data *data; int err; DBG("Bluetooth PCM plugin (%s)", stream == SND_PCM_STREAM_PLAYBACK ? "Playback" : "Capture"); data = malloc(sizeof(struct bluetooth_data)); if (!data) { err = -ENOMEM; goto error; } err = bluetooth_init(data, stream, conf); if (err < 0) goto error; data->io.version = SND_PCM_IOPLUG_VERSION; data->io.name = "Bluetooth Audio Device"; data->io.mmap_rw = 0; /* No direct mmap communication */ data->io.private_data = data; if (data->transport == BT_CAPABILITIES_TRANSPORT_A2DP) data->io.callback = stream == SND_PCM_STREAM_PLAYBACK ? &bluetooth_a2dp_playback : &bluetooth_a2dp_capture; else data->io.callback = stream == SND_PCM_STREAM_PLAYBACK ? &bluetooth_hsp_playback : &bluetooth_hsp_capture; err = snd_pcm_ioplug_create(&data->io, name, stream, mode); if (err < 0) goto error; if (data->transport == BT_CAPABILITIES_TRANSPORT_A2DP) err = bluetooth_a2dp_hw_constraint(&data->io); else err = bluetooth_hsp_hw_constraint(&data->io); if (err < 0) { snd_pcm_ioplug_delete(&data->io); goto error; } *pcmp = data->io.pcm; return 0; error: bluetooth_exit(data); return err; } SND_PCM_PLUGIN_SYMBOL(bluetooth);