[WIP] mobile: integrate V.110 TA from libosmoisdnfixeria/csd_demo

Change-Id: I4a09c0ec72410dd3855b9818cf10598729d6cf8a
Depends: libosmocore.git I5716bd6fd0201ee7a7a29e72f775972cd374082f

6 files changed, 83 insertions, 23 deletions

diff --git a/src/host/layer23/configure.ac b/src/host/layer23/configure.ac
index b4eb8604..7fb8bf16 100644
--- a/src/host/layer23/configure.ac
+++ b/src/host/layer23/configure.ac
@@ -45,6 +45,7 @@ dnl checks for libraries
 PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 1.5.0)
 PKG_CHECK_MODULES(LIBOSMOVTY, libosmovty >= 0.10.0)
 PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm)
+PKG_CHECK_MODULES(LIBOSMOISDN, libosmoisdn)
 PKG_CHECK_MODULES(LIBOSMOCODEC, libosmocodec)
 PKG_CHECK_MODULES(LIBOSMOGPRSRLCMAC, libosmo-gprs-rlcmac)
 PKG_CHECK_MODULES(LIBOSMOGPRSLLC, libosmo-gprs-llc)
diff --git a/src/host/layer23/include/osmocom/bb/mobile/tch.h b/src/host/layer23/include/osmocom/bb/mobile/tch.h
index 4963f174..820f0fb4 100644
--- a/src/host/layer23/include/osmocom/bb/mobile/tch.h
+++ b/src/host/layer23/include/osmocom/bb/mobile/tch.h
@@ -9,12 +9,15 @@ int tch_send_voice_msg(struct osmocom_ms *ms, struct msgb *msg);
 int tch_send_voice_frame(struct osmocom_ms *ms, const struct gsm_data_frame *frame);
 
 int tch_soft_uart_alloc(struct osmocom_ms *ms);
-int tch_soft_uart_rx_from_l1(struct osmocom_ms *ms, struct msgb *msg);
-int tch_soft_uart_tx_to_l1(struct osmocom_ms *ms);
+int tch_v110_ta_alloc(struct osmocom_ms *ms);
+
+int tch_csd_rx_from_l1(struct osmocom_ms *ms, struct msgb *msg);
+int tch_csd_tx_to_l1(struct osmocom_ms *ms);
 
 struct tch_csd_sock_state;
 
 struct tch_csd_sock_state *tch_csd_sock_init(void *ctx, const char *sock_path);
 void tch_csd_sock_exit(struct tch_csd_sock_state *state);
+void tch_csd_sock_conn_cb(struct tch_csd_sock_state *state, bool connected);
 int tch_csd_sock_send(struct tch_csd_sock_state *state, struct msgb *msg);
 int tch_csd_sock_recv(struct tch_csd_sock_state *state, struct msgb *msg);
diff --git a/src/host/layer23/src/mobile/Makefile.am b/src/host/layer23/src/mobile/Makefile.am
index 3583aef2..ddfa13e6 100644
--- a/src/host/layer23/src/mobile/Makefile.am
+++ b/src/host/layer23/src/mobile/Makefile.am
@@ -8,6 +8,7 @@ AM_CFLAGS = \
 	$(LIBOSMOCORE_CFLAGS) \
 	$(LIBOSMOVTY_CFLAGS) \
 	$(LIBOSMOGSM_CFLAGS) \
+	$(LIBOSMOISDN_CFLAGS) \
 	$(LIBOSMOGPRSRLCMAC_CFLAGS) \
 	$(LIBOSMOGPRSLLC_CFLAGS) \
 	$(LIBOSMOGPRSSNDCP_CFLAGS) \
@@ -46,6 +47,7 @@ mobile_LDADD = \
 	$(LIBOSMOCORE_LIBS) \
 	$(LIBOSMOVTY_LIBS) \
 	$(LIBOSMOGSM_LIBS) \
+	$(LIBOSMOISDN_LIBS) \
 	$(LIBOSMOGPRSRLCMAC_LIBS) \
 	$(LIBOSMOGPRSLLC_LIBS) \
 	$(LIBOSMOGPRSSNDCP_LIBS) \
diff --git a/src/host/layer23/src/mobile/tch.c b/src/host/layer23/src/mobile/tch.c
index 4e366327..7ea7f638 100644
--- a/src/host/layer23/src/mobile/tch.c
+++ b/src/host/layer23/src/mobile/tch.c
@@ -45,8 +45,8 @@ static int tch_recv_data(struct osmocom_ms *ms, struct msgb *msg)
 		/* Send data frame back */
 		return tch_send_voice_msg(ms, msg);
 	case TCH_DATA_IOH_UNIX_SOCK:
-		tch_soft_uart_rx_from_l1(ms, msg);
-		tch_soft_uart_tx_to_l1(ms);
+		tch_csd_rx_from_l1(ms, msg);
+		tch_csd_tx_to_l1(ms);
 		msgb_free(msg);
 		break;
 	case TCH_DATA_IOH_NONE:
@@ -173,6 +173,7 @@ int tch_init(struct osmocom_ms *ms)
 	ms->l1_entity.l1_traffic_ind = &tch_recv_data;
 
 	tch_soft_uart_alloc(ms);
+	tch_v110_ta_alloc(ms);
 
 	return 0;
 }
diff --git a/src/host/layer23/src/mobile/tch_csd.c b/src/host/layer23/src/mobile/tch_csd.c
index 1e7ddf6c..7c8914c5 100644
--- a/src/host/layer23/src/mobile/tch_csd.c
+++ b/src/host/layer23/src/mobile/tch_csd.c
@@ -25,7 +25,9 @@
 
 #include <osmocom/gsm/protocol/gsm_08_58.h>
 #include <osmocom/gsm/gsm44021.h>
+
 #include <osmocom/isdn/v110.h>
+#include <osmocom/isdn/v110_ta.h>
 
 #include <osmocom/bb/common/logging.h>
 #include <osmocom/bb/common/osmocom_data.h>
@@ -71,6 +73,7 @@ const struct csd_v110_lchan_desc csd_v110_lchan_desc[256] = {
 /* FIXME: store this in struct osmocom_ms */
 static struct tch_csd_sock_state *g_sock_state;
 static struct osmo_soft_uart *g_suart;
+static struct osmo_v110_ta *g_ta;
 
 static void tch_soft_uart_rx_cb(void *priv, struct msgb *msg, unsigned int flags)
 {
@@ -118,6 +121,46 @@ int tch_soft_uart_alloc(struct osmocom_ms *ms)
 	return 0;
 }
 
+/*************************************************************************************/
+
+static void tch_v110_ta_rx_cb(void *priv, const ubit_t *buf, size_t buf_size)
+{
+	/* XXX: we're assuming async call here */
+	osmo_soft_uart_rx_ubits(g_suart, buf, buf_size);
+}
+
+static void tch_v110_ta_tx_cb(void *priv, ubit_t *buf, size_t buf_size)
+{
+	/* XXX: we're assuming async call here */
+	osmo_soft_uart_tx_ubits(g_suart, buf, buf_size);
+}
+
+static void tch_v110_ta_status_update_cb(void *priv, unsigned int status)
+{
+	LOGP(DL1C, LOGL_DEBUG, "%s(): [status=0x%08x]\n", __func__, status);
+	/* TODO: update status lines of the soft-UART */
+}
+
+int tch_v110_ta_alloc(struct osmocom_ms *ms)
+{
+	const struct osmo_v110_ta_cfg cfg = {
+		/* FIXME: take the exact rate from BCap */
+		.rate = OSMO_V110_SYNC_RA1_9600,
+		.priv = ms,
+		.rx_cb = &tch_v110_ta_rx_cb,
+		.tx_cb = &tch_v110_ta_tx_cb,
+		.status_update_cb = &tch_v110_ta_status_update_cb,
+	};
+
+	g_ta = osmo_v110_ta_alloc(ms, "csd_v110_ta", &cfg);
+	if (g_ta == NULL)
+		return -ENOMEM;
+
+	return 0;
+}
+
+/*************************************************************************************/
+
 static void swap_words(uint8_t *data, size_t data_len)
 {
 	/* swap bytes in words */
@@ -130,7 +173,7 @@ static void swap_words(uint8_t *data, size_t data_len)
 	}
 }
 
-int tch_soft_uart_rx_from_l1(struct osmocom_ms *ms, struct msgb *msg)
+int tch_csd_rx_from_l1(struct osmocom_ms *ms, struct msgb *msg)
 {
 	const struct gsm48_rr_cd *cd = &ms->rrlayer.cd_now;
 	const struct csd_v110_frame_desc *desc;
@@ -161,17 +204,17 @@ int tch_soft_uart_rx_from_l1(struct osmocom_ms *ms, struct msgb *msg)
 	for (unsigned int i = 0; i < desc->num_blocks; i++) {
 		struct osmo_v110_decoded_frame df;
 
-		if (desc->num_bits == 60) {
+		if (desc->num_bits == 60)
 			osmo_csd_12k_6k_decode_frame(&df, &data[i * 60], 60);
-			/* feed D-bits (D1..D48) into the soft-UART */
-			osmo_soft_uart_rx_ubits(g_suart, &df.d_bits[0], 48);
-		} else { /* desc->num_bits == 36 */
+		else /* desc->num_bits == 36 */
 			osmo_csd_3k6_decode_frame(&df, &data[i * 36], 36);
-			/* feed D-bits (D1..D24) into the soft-UART */
-			osmo_soft_uart_rx_ubits(g_suart, &df.d_bits[0], 24);
-		}
 
-		/* XXX: what do we do with S-/X-/E-bits? */
+		/* FIXME: properly set E1/E2/E3 depending on data rate */
+		df.e_bits[0] = 0;
+		df.e_bits[1] = 1;
+		df.e_bits[2] = 1;
+
+		osmo_v110_ta_frame_in(g_ta, &df);
 	}
 
 	osmo_soft_uart_flush_rx(g_suart);
@@ -179,7 +222,7 @@ int tch_soft_uart_rx_from_l1(struct osmocom_ms *ms, struct msgb *msg)
 	return 0;
 }
 
-int tch_soft_uart_tx_to_l1(struct osmocom_ms *ms)
+int tch_csd_tx_to_l1(struct osmocom_ms *ms)
 {
 	const struct gsm48_rr_cd *cd = &ms->rrlayer.cd_now;
 	const struct csd_v110_frame_desc *desc;
@@ -196,18 +239,18 @@ int tch_soft_uart_tx_to_l1(struct osmocom_ms *ms)
 	for (unsigned int i = 0; i < desc->num_blocks; i++) {
 		struct osmo_v110_decoded_frame df;
 
-		/* init all bits to 1 */
-		memset(&df, 0x01, sizeof(df));
+		if (osmo_v110_ta_frame_out(g_ta, &df) != 0)
+			memset(&df, 0x01, sizeof(df));
+
+		/* set E7 to binary 0 in every 4-th frame
+		 * (as per 3GPP TS 44.021, subclause 10.2.1)
+		 * FIXME: properly handle desc->num_blocks == 2 */
+		df.e_bits[6] = (i > 0);
 
-		if (desc->num_bits == 60) {
-			/* pull D-bits (D1..D48) out of the soft-UART */
-			osmo_soft_uart_tx_ubits(g_suart, &df.d_bits[0], 48);
+		if (desc->num_bits == 60)
 			osmo_csd_12k_6k_encode_frame(&data[i * 60], 60, &df);
-		} else { /* desc->num_bits == 36 */
-			/* pull D-bits (D1..D24) out of the soft-UART */
-			osmo_soft_uart_tx_ubits(g_suart, &df.d_bits[0], 24);
+		else /* desc->num_bits == 36 */
 			osmo_csd_3k6_encode_frame(&data[i * 36], 36, &df);
-		}
 	}
 
 	nmsg = msgb_alloc_headroom(33 + 64, 64, __func__);
@@ -229,3 +272,10 @@ int tch_soft_uart_tx_to_l1(struct osmocom_ms *ms)
 
 	return gsm48_rr_tx_traffic(ms, nmsg);
 }
+
+void tch_csd_sock_conn_cb(struct tch_csd_sock_state *state, bool connected)
+{
+	osmo_v110_ta_set_circuit(g_ta, OSMO_V110_TA_C_108, connected);
+}
+
+/* TODO: call osmo_v110_ta_sync_ind() */
diff --git a/src/host/layer23/src/mobile/tch_csd_sock.c b/src/host/layer23/src/mobile/tch_csd_sock.c
index c5cde6cb..fcf95868 100644
--- a/src/host/layer23/src/mobile/tch_csd_sock.c
+++ b/src/host/layer23/src/mobile/tch_csd_sock.c
@@ -90,6 +90,7 @@ static int tch_csd_sock_read(struct osmo_fd *bfd)
 close:
 	msgb_free(msg);
 	tch_csd_sock_close(state);
+	tch_csd_sock_conn_cb(state, false);
 	return -1;
 }
 
@@ -175,6 +176,8 @@ static int tch_csd_sock_accept(struct osmo_fd *bfd, unsigned int flags)
 
 	LOGP(DMOB, LOGL_NOTICE, "TCH CSD sock got a connection\n");
 
+	tch_csd_sock_conn_cb(state, true);
+
 	return 0;
 }