Add prototype version of the A2DP plugin

1 files changed, 358 insertions, 0 deletions

diff --git a/alsa/pcm_a2dp.c b/alsa/pcm_a2dp.c
index e69de29b..90ee7107 100644
--- a/alsa/pcm_a2dp.c
+++ b/alsa/pcm_a2dp.c
@@ -0,0 +1,358 @@
+/*
+ *
+ *  BlueZ - Bluetooth protocol stack for Linux
+ *
+ *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>
+ *
+ *
+ *  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <errno.h>
+#include <malloc.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+
+#include <bluetooth/bluetooth.h>
+#include <bluetooth/rfcomm.h>
+
+#include <alsa/asoundlib.h>
+#include <alsa/pcm_external.h>
+
+#include "sbc.h"
+
+//#define DBG(fmt, arg...)  printf("DEBUG: %s: " fmt "\n" , __FUNCTION__ , ## arg)
+#define DBG(D...)
+
+typedef struct snd_pcm_a2dp {
+	snd_pcm_ioplug_t io;
+	bdaddr_t src;
+	bdaddr_t dst;
+	int sk;
+	sbc_t sbc;
+	snd_pcm_sframes_t num;
+	unsigned char buf[1024];
+	unsigned int len;
+	unsigned int frame_bytes;
+} snd_pcm_a2dp_t;
+
+static int a2dp_start(snd_pcm_ioplug_t *io)
+{
+	snd_pcm_a2dp_t *a2dp = io->private_data;
+
+	DBG("a2dp %p", a2dp);
+
+	a2dp->len = 0;
+
+	return 0;
+}
+
+static int a2dp_stop(snd_pcm_ioplug_t *io)
+{
+	snd_pcm_a2dp_t *a2dp = io->private_data;
+
+	DBG("a2dp %p", a2dp);
+
+	a2dp->len = 0;
+
+	return 0;
+}
+
+static snd_pcm_sframes_t a2dp_pointer(snd_pcm_ioplug_t *io)
+{
+	snd_pcm_a2dp_t *a2dp = io->private_data;
+
+	return a2dp->num;
+}
+
+static snd_pcm_sframes_t a2dp_transfer(snd_pcm_ioplug_t *io,
+			const snd_pcm_channel_area_t *areas,
+			snd_pcm_uframes_t offset, snd_pcm_uframes_t size)
+{
+	snd_pcm_a2dp_t *a2dp = io->private_data;
+	unsigned char *buf;
+	int len;
+
+	buf = (unsigned char *) areas->addr + (areas->first + areas->step * offset) / 8;
+
+	size *= a2dp->frame_bytes;
+
+	len = sbc_encode(&a2dp->sbc, buf, size);
+	if (len <= 0)
+		return len;
+
+	memcpy(a2dp->buf + a2dp->len, a2dp->sbc.data, a2dp->sbc.len);
+	a2dp->len += a2dp->sbc.len;
+
+	if (a2dp->len > 700) {
+		write(a2dp->sk, a2dp->buf, a2dp->len);
+		a2dp->len = 0;
+	}
+
+	a2dp->num += len / a2dp->frame_bytes;
+
+	return len / a2dp->frame_bytes;
+}
+
+static int a2dp_close(snd_pcm_ioplug_t *io)
+{
+	snd_pcm_a2dp_t *a2dp = io->private_data;
+
+	DBG("a2dp %p", a2dp);
+
+	a2dp->len = 0;
+
+	if (a2dp->sk >= 0) {
+		shutdown(a2dp->sk, SHUT_RDWR);
+		sleep(1);
+		close(a2dp->sk);
+	}
+
+	sbc_finish(&a2dp->sbc);
+
+	free(a2dp);
+	return 0;
+}
+
+static int a2dp_params(snd_pcm_ioplug_t *io, snd_pcm_hw_params_t *params)
+{
+	snd_pcm_a2dp_t *a2dp = io->private_data;
+	unsigned int period_bytes;
+
+	DBG("a2dp %p", a2dp);
+
+	a2dp->frame_bytes = (snd_pcm_format_physical_width(io->format) * io->channels) / 8;
+
+	period_bytes = io->period_size * a2dp->frame_bytes;
+
+	DBG("format %s rate %d channels %d", snd_pcm_format_name(io->format),
+					io->rate, io->channels);
+
+	DBG("frame_bytes %d period_byts %d period_size %ld buffer_size %ld",
+		a2dp->frame_bytes, period_bytes, io->period_size, io->buffer_size);
+
+	return 0;
+}
+
+static int a2dp_prepare(snd_pcm_ioplug_t *io)
+{
+	snd_pcm_a2dp_t *a2dp = io->private_data;
+
+	DBG("a2dp %p", a2dp);
+
+	a2dp->sbc.rate = io->rate;
+	a2dp->sbc.channels = io->channels;
+
+	return 0;
+}
+
+static int a2dp_drain(snd_pcm_ioplug_t *io)
+{
+	snd_pcm_a2dp_t *a2dp = io->private_data;
+
+	DBG("a2dp %p", a2dp);
+
+	a2dp->len = 0;
+
+	return 0;
+}
+
+static snd_pcm_ioplug_callback_t a2dp_callback = {
+	.start		= a2dp_start,
+	.stop		= a2dp_stop,
+	.pointer	= a2dp_pointer,
+	.transfer	= a2dp_transfer,
+	.close		= a2dp_close,
+	.hw_params	= a2dp_params,
+	.prepare	= a2dp_prepare,
+	.drain		= a2dp_drain,
+};
+
+static int a2dp_connect(snd_pcm_a2dp_t *a2dp)
+{
+	struct sockaddr_rc addr;
+	int sk;
+
+	DBG("a2dp %p", a2dp);
+
+	sk = socket(PF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM);
+	if (sk < 0)
+		return -errno;
+
+	memset(&addr, 0, sizeof(addr));
+	addr.rc_family = AF_BLUETOOTH;
+	bacpy(&addr.rc_bdaddr, &a2dp->src);
+
+	if (bind(sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
+		close(sk);
+		return -errno;
+	}
+
+	memset(&addr, 0, sizeof(addr));
+	addr.rc_family = AF_BLUETOOTH;
+	bacpy(&addr.rc_bdaddr, &a2dp->dst);
+	addr.rc_channel = 1;
+
+	if (connect(sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
+		close(sk);
+		return -errno;
+	}
+
+	a2dp->sk = sk;
+	return 0;
+}
+
+static int a2dp_constraint(snd_pcm_a2dp_t *a2dp)
+{
+	snd_pcm_ioplug_t *io = &a2dp->io;
+	snd_pcm_access_t access_list[] = {
+		SND_PCM_ACCESS_RW_INTERLEAVED,
+		SND_PCM_ACCESS_MMAP_INTERLEAVED,
+	};
+	unsigned int format[2], channel[2], rate[2];
+	int err;
+
+	DBG("a2dp %p", a2dp);
+
+	err = snd_pcm_ioplug_set_param_list(io, SND_PCM_IOPLUG_HW_ACCESS, 2, access_list);
+	if (err < 0)
+		return err;
+
+	format[0] = SND_PCM_FORMAT_S16_LE;
+
+	err = snd_pcm_ioplug_set_param_list(io, SND_PCM_IOPLUG_HW_FORMAT, 1, format);
+	if (err < 0)
+		return err;
+
+	channel[0] = 1;
+	channel[1] = 2;
+
+	err = snd_pcm_ioplug_set_param_list(io, SND_PCM_IOPLUG_HW_CHANNELS, 2, channel);
+	if (err < 0)
+		return err;
+
+	rate[0] = 44100;
+	rate[1] = 48000;
+
+	err = snd_pcm_ioplug_set_param_list(io, SND_PCM_IOPLUG_HW_RATE, 2, rate);
+	if (err < 0)
+		return err;
+
+	err = snd_pcm_ioplug_set_param_minmax(io, SND_PCM_IOPLUG_HW_PERIOD_BYTES, 2048, 2048);
+	if (err < 0)
+		return err;
+
+	err = snd_pcm_ioplug_set_param_minmax(io, SND_PCM_IOPLUG_HW_PERIODS, 2, 2);
+	if (err < 0)
+		return err;
+
+	sbc_init(&a2dp->sbc, SBC_NULL);
+
+	return 0;
+}
+
+SND_PCM_PLUGIN_DEFINE_FUNC(a2dp)
+{
+	snd_pcm_a2dp_t *a2dp;
+	snd_config_iterator_t i, next;
+	bdaddr_t src, dst;
+	int err;
+
+	DBG("name %s mode %d", name, mode);
+
+	bacpy(&src, BDADDR_ANY);
+	bacpy(&dst, BDADDR_ANY);
+
+	snd_config_for_each(i, next, conf) {
+		snd_config_t *n = snd_config_iterator_entry(i);
+		const char *id, *addr;
+
+		if (snd_config_get_id(n, &id) < 0)
+			continue;
+
+		if (!strcmp(id, "comment") || !strcmp(id, "type"))
+			continue;
+
+		if (!strcmp(id, "bdaddr") || !strcmp(id, "dst")) {
+			if (snd_config_get_string(n, &addr) < 0) {
+				SNDERR("Invalid type for %s", id);
+				return -EINVAL;
+			}
+			str2ba(addr, &dst);
+			continue;
+		}
+
+		if (strcmp(id, "src") == 0) {
+			if (snd_config_get_string(n, &addr) < 0) {
+				SNDERR("Invalid type for %s", id);
+				return -EINVAL;
+			}
+			str2ba(addr, &src);
+			continue;
+		}
+
+		SNDERR("Unknown field %s", id);
+		return -EINVAL;
+	}
+
+	a2dp = malloc(sizeof(*a2dp));
+	if (!a2dp) {
+		SNDERR("Cannot allocate");
+		return -ENOMEM;
+	}
+
+	memset(a2dp, 0, sizeof(*a2dp));
+
+	bacpy(&a2dp->src, &src);
+	bacpy(&a2dp->dst, &dst);
+
+	err = a2dp_connect(a2dp);
+	if (err < 0) {
+		SNDERR("Cannot connect");
+		goto error;
+	}
+
+	a2dp->io.name = "Bluetooth Advanced Audio Distribution";
+	a2dp->io.poll_fd = a2dp->sk;
+	a2dp->io.poll_events = POLLOUT | POLLHUP;
+	a2dp->io.mmap_rw = 0;
+	a2dp->io.callback = &a2dp_callback;
+	a2dp->io.private_data = a2dp;
+
+	err = snd_pcm_ioplug_create(&a2dp->io, name, stream, mode);
+	if (err < 0)
+		goto error;
+
+	err = a2dp_constraint(a2dp);
+	if (err < 0) {
+		snd_pcm_ioplug_delete(&a2dp->io);
+		return err;
+	}
+
+	*pcmp = a2dp->io.pcm;
+	return 0;
+
+error:
+	free(a2dp);
+	return err;
+}
+
+SND_PCM_PLUGIN_SYMBOL(a2dp);