mobile: init/deinit GAPK I/O based on CC transaction events

Change-Id: I28f87f6a6de673611aa02a24e8985aee23d4498b
Related: OS#4396

4 files changed, 230 insertions, 114 deletions

diff --git a/src/host/layer23/src/mobile/app_mobile.c b/src/host/layer23/src/mobile/app_mobile.c
index e2ef56a1..453990ee 100644
--- a/src/host/layer23/src/mobile/app_mobile.c
+++ b/src/host/layer23/src/mobile/app_mobile.c
@@ -42,7 +42,6 @@
 #include <osmocom/bb/mobile/app_mobile.h>
 #include <osmocom/bb/mobile/mncc.h>
 #include <osmocom/bb/mobile/tch.h>
-#include <osmocom/bb/mobile/gapk_io.h>
 #include <osmocom/bb/mobile/primitives.h>
 
 #include <osmocom/vty/vty.h>
@@ -82,10 +81,7 @@ int mobile_work(struct osmocom_ms *ms)
 		w |= gsm322_cs_dequeue(ms);
 		w |= gsm_sim_job_dequeue(ms);
 		w |= mncc_dequeue(ms);
-#ifdef WITH_GAPK_IO
-		if (ms->gapk_io != NULL)
-			w |= gapk_io_serve_ms(ms);
-#endif
+		w |= tch_serve_ms(ms);
 		if (w)
 			work = 1;
 	} while (w);
@@ -200,12 +196,6 @@ int mobile_exit(struct osmocom_ms *ms, int force)
 		return -EBUSY;
 	}
 
-#ifdef WITH_GAPK_IO
-	/* Clean up GAPK state, if preset */
-	if (ms->gapk_io != NULL)
-		gapk_io_clean_up_ms(ms);
-#endif
-
 	gsm322_exit(ms);
 	gsm48_mm_exit(ms);
 	gsm48_rr_exit(ms);
@@ -494,11 +484,6 @@ int l23_app_init(void)
 	l23_app_exit = _mobile_app_exit;
 	osmo_gps_init();
 
-#ifdef WITH_GAPK_IO
-	/* Init GAPK audio I/O */
-	gapk_io_init();
-#endif
-
 	osmo_signal_register_handler(SS_GLOBAL, &global_signal_cb, NULL);
 	osmo_signal_register_handler(SS_L1CTL, &mobile_signal_cb, NULL);
 	osmo_signal_register_handler(SS_L1CTL, &gsm322_l1_signal, NULL);
diff --git a/src/host/layer23/src/mobile/gapk_io.c b/src/host/layer23/src/mobile/gapk_io.c
index 9a97639d..3dab46df 100644
--- a/src/host/layer23/src/mobile/gapk_io.c
+++ b/src/host/layer23/src/mobile/gapk_io.c
@@ -316,29 +316,26 @@ error:
  * processing queues (chains), and deallocates the memory.
  * Should be called when a voice call is finished...
  */
-int gapk_io_clean_up_ms(struct osmocom_ms *ms)
+void gapk_io_state_free(struct gapk_io_state *state)
 {
 	struct msgb *msg;
 
-	if (ms->gapk_io == NULL)
-		return 0;
+	if (state == NULL)
+		return;
 
 	/* Flush TCH frame I/O buffers */
-	while ((msg = msgb_dequeue(&ms->gapk_io->tch_dl_fb)))
+	while ((msg = msgb_dequeue(&state->tch_dl_fb)))
 		msgb_free(msg);
-	while ((msg = msgb_dequeue(&ms->gapk_io->tch_ul_fb)))
+	while ((msg = msgb_dequeue(&state->tch_ul_fb)))
 		msgb_free(msg);
 
 	/* Destroy both audio I/O chains */
-	if (ms->gapk_io->pq_source)
-		osmo_gapk_pq_destroy(ms->gapk_io->pq_source);
-	if (ms->gapk_io->pq_sink)
-		osmo_gapk_pq_destroy(ms->gapk_io->pq_sink);
-
-	talloc_free(ms->gapk_io);
-	ms->gapk_io = NULL;
+	if (state->pq_source != NULL)
+		osmo_gapk_pq_destroy(state->pq_source);
+	if (state->pq_sink != NULL)
+		osmo_gapk_pq_destroy(state->pq_sink);
 
-	return 0;
+	talloc_free(state);
 }
 
 /**
@@ -386,31 +383,31 @@ static enum osmo_gapk_format_type phy_fmt_pick_ti(enum osmo_gapk_codec_type code
  * and prepares both processing queues (chains).
  * Should be called when a voice call is initiated...
  */
-int gapk_io_init_ms(struct osmocom_ms *ms, enum osmo_gapk_codec_type codec)
+struct gapk_io_state *
+gapk_io_state_alloc(struct osmocom_ms *ms,
+		    enum osmo_gapk_codec_type codec)
 {
 	const struct osmo_gapk_format_desc *phy_fmt_desc;
 	const struct osmo_gapk_codec_desc *codec_desc;
-	struct gsm_settings *set = &ms->settings;
+	const struct gsm_settings *set = &ms->settings;
 	enum osmo_gapk_format_type phy_fmt;
 	struct gapk_io_state *state;
 	int rc = 0;
 
 	LOGP(DGAPK, LOGL_NOTICE, "Initialize GAPK I/O\n");
 
-	OSMO_ASSERT(ms->gapk_io == NULL);
-
 	/* Make sure that the chosen codec has description */
 	codec_desc = osmo_gapk_codec_get_from_type(codec);
 	if (codec_desc == NULL) {
 		LOGP(DGAPK, LOGL_ERROR, "Invalid codec type 0x%02x\n", codec);
-		return -EINVAL;
+		return NULL;
 	}
 
 	/* Make sure that the chosen codec is supported */
 	if (codec_desc->codec_encode == NULL || codec_desc->codec_decode == NULL) {
 		LOGP(DGAPK, LOGL_ERROR,
 		     "Codec '%s' is not supported by GAPK\n", codec_desc->name);
-		return -ENOTSUP;
+		return NULL;
 	}
 
 	switch (set->tch_voice.io_format) {
@@ -423,20 +420,20 @@ int gapk_io_init_ms(struct osmocom_ms *ms, enum osmo_gapk_codec_type codec)
 	default:
 		LOGP(DGAPK, LOGL_ERROR, "Unhandled I/O format %s\n",
 		     tch_voice_io_format_name(set->tch_voice.io_format));
-		return -ENOTSUP;
+		return NULL;
 	}
 
 	phy_fmt_desc = osmo_gapk_fmt_get_from_type(phy_fmt);
 	if (phy_fmt_desc == NULL) {
 		LOGP(DGAPK, LOGL_ERROR, "Failed to pick the PHY specific "
 		     "frame format for codec '%s'\n", codec_desc->name);
-		return -EINVAL;
+		return NULL;
 	}
 
 	state = talloc_zero(ms, struct gapk_io_state);
 	if (state == NULL) {
 		LOGP(DGAPK, LOGL_ERROR, "Failed to allocate memory\n");
-		return -ENOMEM;
+		return NULL;
 	}
 
 	/* Init TCH frame I/O buffers */
@@ -469,76 +466,41 @@ int gapk_io_init_ms(struct osmocom_ms *ms, enum osmo_gapk_codec_type codec)
 		talloc_free(state);
 
 		LOGP(DGAPK, LOGL_ERROR, "Failed to initialize GAPK I/O\n");
-		return rc;
+		return NULL;
 	}
 
-	/* Init pointers */
-	ms->gapk_io = state;
-
 	LOGP(DGAPK, LOGL_NOTICE,
 	     "GAPK I/O initialized for MS '%s', codec '%s'\n",
 	     ms->name, codec_desc->name);
 
-	return 0;
+	return state;
 }
 
-/**
- * Wrapper around gapk_io_init_ms(), that maps both
- * given GSM 04.08 channel type (HR/FR) and channel
- * mode to a codec from 'osmo_gapk_codec_type' enum,
- * checks if a mapped codec is supported by GAPK,
- * and finally calls the wrapped function.
- */
-int gapk_io_init_ms_chan(struct osmocom_ms *ms,
-			 uint8_t ch_type, uint8_t ch_mode)
+/* gapk_io_init_ms() wrapper, selecting a codec based on channel mode and rate */
+struct gapk_io_state *
+gapk_io_state_alloc_mode_rate(struct osmocom_ms *ms,
+			      enum gsm48_chan_mode ch_mode,
+			      bool full_rate)
 {
 	enum osmo_gapk_codec_type codec;
 
-	/* Map GSM 04.08 channel mode to GAPK codec type */
 	switch (ch_mode) {
 	case GSM48_CMODE_SPEECH_V1: /* FR or HR */
-		if (ch_type == RSL_CHAN_Bm_ACCHs)
-			codec = CODEC_FR;
-		else
-			codec = CODEC_HR;
+		codec = full_rate ? CODEC_FR : CODEC_HR;
 		break;
-
 	case GSM48_CMODE_SPEECH_EFR:
 		codec = CODEC_EFR;
 		break;
-
 	case GSM48_CMODE_SPEECH_AMR:
 		codec = CODEC_AMR;
 		break;
-
-	/* Signalling or CSD, do nothing */
-	case GSM48_CMODE_DATA_14k5:
-	case GSM48_CMODE_DATA_12k0:
-	case GSM48_CMODE_DATA_6k0:
-	case GSM48_CMODE_DATA_3k6:
-	case GSM48_CMODE_SIGN:
-		return 0;
 	default:
 		LOGP(DGAPK, LOGL_ERROR, "Unhandled channel mode 0x%02x (%s)\n",
 		     ch_mode, get_value_string(gsm48_chan_mode_names, ch_mode));
-		return -EINVAL;
+		return NULL;
 	}
 
-	return gapk_io_init_ms(ms, codec);
-}
-
-/**
- * Performs basic initialization of GAPK library,
- * setting the talloc root context and a logging category.
- * Should be called during the application initialization...
- */
-void gapk_io_init(void)
-{
-	/* Init logging subsystem */
-	osmo_gapk_log_init(DGAPK);
-
-	/* Make RAWPCM format info easy to access */
-	rawpcm_fmt = osmo_gapk_fmt_get_from_type(FMT_RAWPCM_S16LE);
+	return gapk_io_state_alloc(ms, codec);
 }
 
 void gapk_io_enqueue_dl(struct gapk_io_state *state, struct msgb *msg)
@@ -554,9 +516,8 @@ void gapk_io_enqueue_dl(struct gapk_io_state *state, struct msgb *msg)
 }
 
 /* Serves both UL/DL TCH frame I/O buffers */
-int gapk_io_serve_ms(struct osmocom_ms *ms)
+int gapk_io_serve_ms(struct osmocom_ms *ms, struct gapk_io_state *state)
 {
-	struct gapk_io_state *state = ms->gapk_io;
 	int work = 0;
 
 	/**
@@ -596,3 +557,16 @@ int gapk_io_serve_ms(struct osmocom_ms *ms)
 
 	return work;
 }
+
+/**
+ * Performs basic initialization of GAPK library,
+ * setting the talloc root context and a logging category.
+ */
+static __attribute__((constructor)) void gapk_io_init(void)
+{
+	/* Init logging subsystem */
+	osmo_gapk_log_init(DGAPK);
+
+	/* Make RAWPCM format info easy to access */
+	rawpcm_fmt = osmo_gapk_fmt_get_from_type(FMT_RAWPCM_S16LE);
+}
diff --git a/src/host/layer23/src/mobile/gsm48_rr.c b/src/host/layer23/src/mobile/gsm48_rr.c
index 46a143cd..4d879d6f 100644
--- a/src/host/layer23/src/mobile/gsm48_rr.c
+++ b/src/host/layer23/src/mobile/gsm48_rr.c
@@ -125,7 +125,6 @@
 #include <osmocom/bb/common/utils.h>
 #include <osmocom/bb/common/settings.h>
 
-#include <osmocom/bb/mobile/gapk_io.h>
 #include <osmocom/bb/mobile/vty.h>
 #include <osmocom/bb/mobile/gsm48_rr.h>
 
@@ -515,10 +514,6 @@ static void new_rr_state(struct gsm48_rrlayer *rr, int state)
 		memset(&rr->cd_now, 0, sizeof(rr->cd_now));
 		/* reset ciphering */
 		rr->cipher_on = 0;
-#ifdef WITH_GAPK_IO
-		/* clean-up GAPK state */
-		gapk_io_clean_up_ms(rr->ms);
-#endif
 		/* reset audio mode */
 		/* tell cell selection process to return to idle mode
 		 * NOTE: this must be sent unbuffered, because it will
@@ -573,10 +568,6 @@ static void new_rr_state(struct gsm48_rrlayer *rr, int state)
 		gsm48_rr_render_ma(ms, &rr->cd_now, ma, &ma_len);
 		/* activate channel */
 		gsm48_rr_activate_channel(ms, &rr->cd_now, ma, ma_len);
-#ifdef WITH_GAPK_IO
-		/* clean-up GAPK state */
-		gapk_io_clean_up_ms(rr->ms);
-#endif
 		return;
 	}
 }
@@ -4432,15 +4423,6 @@ static int gsm48_rr_set_mode(struct osmocom_ms *ms, uint8_t chan_nr, uint8_t mod
 	 && ch_type != RSL_CHAN_Lm_ACCHs)
 		return -ENOTSUP;
 
-#ifdef WITH_GAPK_IO
-	/* Poke GAPK audio back-end, if it is chosen */
-	if (ms->settings.tch_voice.io_handler == TCH_VOICE_IOH_GAPK) {
-		int rc = gapk_io_init_ms_chan(ms, ch_type, mode);
-		if (rc)
-			return rc;
-	}
-#endif
-
 	/* Apply indicated channel mode */
 	LOGP(DRR, LOGL_INFO, "setting TCH mode to %s, audio mode to %d, tch flags to %d\n",
 	     get_value_string(gsm48_chan_mode_names, mode), rr->audio_mode, tch_flags);
@@ -4984,12 +4966,6 @@ static int gsm48_rr_rx_ass_cmd(struct osmocom_ms *ms, struct msgb *msg)
 	if (cause)
 		return gsm48_rr_tx_ass_fail(ms, cause, RSL_MT_DATA_REQ);
 
-#ifdef WITH_GAPK_IO
-	/* Poke GAPK audio back-end, if it is chosen */
-	if (ms->settings.tch_voice.io_handler == TCH_VOICE_IOH_GAPK)
-		gapk_io_init_ms_chan(ms, ch_type, cda->mode);
-#endif
-
 #ifdef TEST_FREQUENCY_MOD
 	LOGP(DRR, LOGL_INFO, " TESTING: frequency modify ASS.CMD\n");
 	before_time = 1;
diff --git a/src/host/layer23/src/mobile/tch.c b/src/host/layer23/src/mobile/tch.c
index f6530fba..0b9142e3 100644
--- a/src/host/layer23/src/mobile/tch.c
+++ b/src/host/layer23/src/mobile/tch.c
@@ -1,7 +1,7 @@
 /*
  * (C) 2010 by Andreas Eversberg <jolly@eversberg.eu>
  * (C) 2017-2018 by Vadim Yanitskiy <axilirator@gmail.com>
- * (C) 2022 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
+ * (C) 2022-2024 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
  *
  * All Rights Reserved
  *
@@ -21,8 +21,10 @@
 #include <errno.h>
 
 #include <osmocom/core/msgb.h>
+#include <osmocom/core/signal.h>
 #include <osmocom/codec/codec.h>
 
+#include <osmocom/gsm/protocol/gsm_04_08.h>
 #include <osmocom/gsm/protocol/gsm_08_58.h>
 
 #include <osmocom/bb/common/logging.h>
@@ -31,6 +33,7 @@
 #include <osmocom/bb/mobile/gapk_io.h>
 #include <osmocom/bb/mobile/mncc.h>
 #include <osmocom/bb/mobile/mncc_sock.h>
+#include <osmocom/bb/mobile/transaction.h>
 #include <osmocom/bb/mobile/tch.h>
 
 /* Forward a Downlink voice frame to the external MNCC handler */
@@ -76,7 +79,9 @@ exit_free:
 /* Receive a Downlink voice frame from the lower layers */
 static int tch_recv_voice(struct osmocom_ms *ms, struct msgb *msg)
 {
-	switch (ms->settings.tch_voice.io_handler) {
+	struct tch_state *state = ms->tch_state;
+
+	switch (state->voice.handler) {
 	case TCH_VOICE_IOH_LOOPBACK:
 		/* Remove the DL info header */
 		msgb_pull_to_l2(msg);
@@ -87,8 +92,8 @@ static int tch_recv_voice(struct osmocom_ms *ms, struct msgb *msg)
 	case TCH_VOICE_IOH_GAPK:
 #ifdef WITH_GAPK_IO
 		/* Enqueue a frame to the DL TCH buffer */
-		if (ms->gapk_io != NULL)
-			gapk_io_enqueue_dl(ms->gapk_io, msg);
+		if (state->voice.gapk_io != NULL)
+			gapk_io_enqueue_dl(state->voice.gapk_io, msg);
 		else
 			msgb_free(msg);
 		break;
@@ -102,6 +107,25 @@ static int tch_recv_voice(struct osmocom_ms *ms, struct msgb *msg)
 	return 0;
 }
 
+/* Receive a Downlink traffic (voice/data) frame from the lower layers */
+static int tch_recv_cb(struct osmocom_ms *ms, struct msgb *msg)
+{
+	struct tch_state *state = ms->tch_state;
+	int rc = 0;
+
+	if (state == NULL) {
+		msgb_free(msg);
+		return 0;
+	}
+
+	if (state->is_voice)
+		rc = tch_recv_voice(ms, msg);
+	else /* TODO: tch_recv_data() */
+		msgb_free(msg);
+
+	return rc;
+}
+
 /* Send an Uplink voice frame to the lower layers */
 int tch_send_voice_msg(struct osmocom_ms *ms, struct msgb *msg)
 {
@@ -142,10 +166,167 @@ int tch_send_voice_frame(struct osmocom_ms *ms, const struct gsm_data_frame *fra
 	return tch_send_voice_msg(ms, nmsg);
 }
 
+int tch_serve_ms(struct osmocom_ms *ms)
+{
+	struct tch_state *state = ms->tch_state;
+
+	if (state == NULL)
+		return 0;
+	if (state->is_voice) {
+#ifdef WITH_GAPK_IO
+		if (state->voice.handler == TCH_VOICE_IOH_GAPK)
+			return gapk_io_serve_ms(ms, state->voice.gapk_io);
+#endif
+	}
+
+	return 0;
+}
+
+static int tch_state_init_voice(struct osmocom_ms *ms,
+				struct tch_voice_state *state)
+{
+	const struct gsm48_rr_cd *cd = &ms->rrlayer.cd_now;
+
+	switch (state->handler) {
+#ifdef WITH_GAPK_IO
+	case TCH_VOICE_IOH_GAPK:
+		if ((cd->chan_nr & RSL_CHAN_NR_MASK) == RSL_CHAN_Bm_ACCHs)
+			state->gapk_io = gapk_io_state_alloc_mode_rate(ms, cd->mode, true);
+		else /* RSL_CHAN_Lm_ACCHs */
+			state->gapk_io = gapk_io_state_alloc_mode_rate(ms, cd->mode, false);
+		if (state->gapk_io == NULL)
+			return -1;
+		break;
+#endif
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static void tch_state_free_voice(struct tch_voice_state *state)
+{
+	switch (state->handler) {
+#ifdef WITH_GAPK_IO
+	case TCH_VOICE_IOH_GAPK:
+		gapk_io_state_free(state->gapk_io);
+		break;
+#endif
+	default:
+		break;
+	}
+}
+
+static void tch_trans_cstate_active_cb(struct gsm_trans *trans)
+{
+	struct osmocom_ms *ms = trans->ms;
+	struct tch_state *state;
+	enum gsm48_chan_mode ch_mode;
+
+	if (ms->tch_state != NULL)
+		return; /* TODO: handle modify? */
+
+	state = talloc_zero(ms, struct tch_state);
+	OSMO_ASSERT(state != NULL);
+
+	ch_mode = ms->rrlayer.cd_now.mode;
+	switch (ch_mode) {
+	case GSM48_CMODE_SPEECH_V1:
+	case GSM48_CMODE_SPEECH_EFR:
+	case GSM48_CMODE_SPEECH_AMR:
+		state->is_voice = true;
+		state->voice.handler = ms->settings.tch_voice.io_handler;
+		if (tch_state_init_voice(ms, &state->voice) != 0)
+			goto exit_free;
+		break;
+	case GSM48_CMODE_DATA_14k5:
+	case GSM48_CMODE_DATA_12k0:
+	case GSM48_CMODE_DATA_6k0:
+	case GSM48_CMODE_DATA_3k6:
+#if 0
+		state->is_voice = false;
+		state->data.handler = ms->settings.tch_data.io_handler;
+		/* TODO: tch_state_init_data() */
+		if (tch_state_init_data(ms, &state->data) != 0)
+			goto exit_free;
+		break;
+#endif
+	case GSM48_CMODE_SIGN:
+	default:
+		LOGP(DL1C, LOGL_ERROR, "Unhandled channel mode %s\n",
+		     get_value_string(gsm48_chan_mode_names, ch_mode));
+exit_free:
+		talloc_free(state);
+		return;
+	}
+
+	ms->tch_state = state;
+}
+
+static void tch_trans_free_cb(struct gsm_trans *trans)
+{
+	struct osmocom_ms *ms = trans->ms;
+	struct tch_state *state = ms->tch_state;
+
+	if (state == NULL)
+		return;
+	if (state->is_voice)
+		tch_state_free_voice(&state->voice);
+#if 0
+	else /* TODO: tch_state_free_data() */
+		tch_state_free_data(&state->data);
+#endif
+
+	talloc_free(state);
+	ms->tch_state = NULL;
+}
+
+static void tch_trans_state_chg_cb(struct gsm_trans *trans)
+{
+	switch (trans->cc.state) {
+	case GSM_CSTATE_ACTIVE:
+		tch_trans_cstate_active_cb(trans);
+		break;
+	case GSM_CSTATE_NULL:
+		tch_trans_free_cb(trans);
+		break;
+	}
+}
+
+/* a call-back for CC (Call Control) transaction related events */
+static int tch_trans_signal_cb(unsigned int subsys, unsigned int signal,
+			       void *handler_data, void *signal_data)
+{
+	struct gsm_trans *trans = signal_data;
+
+	OSMO_ASSERT(subsys == SS_L23_TRANS);
+	OSMO_ASSERT(trans != NULL);
+
+	/* we only care about CC transactions here */
+	if (trans->protocol != GSM48_PDISC_CC)
+		return 0;
+
+	switch ((enum osmobb_l23_trans_sig)signal) {
+	case S_L23_CC_TRANS_ALLOC:
+		break;
+	case S_L23_CC_TRANS_FREE:
+		tch_trans_free_cb(trans);
+		break;
+	case S_L23_CC_TRANS_STATE_CHG:
+		tch_trans_state_chg_cb(trans);
+		break;
+	}
+
+	return 0;
+}
+
 /* Initialize the TCH router */
 int tch_init(struct osmocom_ms *ms)
 {
-	ms->l1_entity.l1_traffic_ind = tch_recv_voice;
+	ms->l1_entity.l1_traffic_ind = &tch_recv_cb;
+
+	osmo_signal_register_handler(SS_L23_TRANS, &tch_trans_signal_cb, ms);
 
 	return 0;
 }