AMR: WIPlaforge/trau

Change-Id: I09e3c6cc8139d7be042278775b8de0b223513d53

3 files changed, 258 insertions, 75 deletions

diff --git a/contrib/trau2rtp/trau2rtp.c b/contrib/trau2rtp/trau2rtp.c
index fc9462d..7a29f4c 100644
--- a/contrib/trau2rtp/trau2rtp.c
+++ b/contrib/trau2rtp/trau2rtp.c
@@ -35,7 +35,7 @@ const int g_remote_port = 9000;
 const int g_local_port = 8000;
 
 /* codec; can be OSMO_TRAU16_FT_FR or OSMO_TRAU16_FT_EFR */
-const enum osmo_trau_frame_type g_ftype = OSMO_TRAU16_FT_EFR;
+const enum osmo_trau_frame_type g_ftype = OSMO_TRAU16_FT_AMR;
 
 /***********************************************************************
  * END CONFIGURATION
@@ -114,21 +114,35 @@ static void sync_frame_out_cb(void *user_data, const ubit_t *bits, unsigned int
 	if (g_local_loop) {
 		/* Mirror back to other sub-slot */
 		struct sc_state *peer = opposite_schan(sc);
-		if (peer) {
-			struct msgb *msg = msgb_alloc(2*40*8, "mirror");
+		if (!peer)
+			return;
+
+		struct msgb *msg = msgb_alloc(2*40*8, "mirror");
+
+		if (fr.type == OSMO_TRAU16_FT_AMR) {
+			//fr.c_bits[12-1] = FIXME; /* Req/Ind flag; use from UL */
+			fr.c_bits[13-1] = 1; /* UFT: no errors */
+			memset(&fr.c_bits[14-1], 0, 3); /* Config_Prot: no TFO */
+			memset(&fr.c_bits[17-1], 0, 2); /* Message_No: no TFO */
+			fr.c_bits[19-1] = 1; /* Reserved */
+			fr.c_bits[20-1] = 1; /* Reserved */
+
+		} else {
 			fr.c_bits[12-1] = 1; /* C12 = good u-link frame */
 			memset(&fr.c_bits[13-1], 1, 3); /* C13..C15: spare  */
 			fr.c_bits[16-1] = 1; /* C16 = SP[eech]; no DTX */
 			memset(&fr.c_bits[6-1], 0, 6); /* C6..C11: tie alignment */
-			fr.dir = OSMO_TRAU_DIR_DL;
-			rc = osmo_trau_frame_encode(msgb_data(msg), 2*40*8, &fr);
-			OSMO_ASSERT(rc >= 0);
-			msgb_put(msg, rc);
-			osmo_i460_mux_enqueue(peer->i460_sc, msg);
 		}
+		fr.dir = OSMO_TRAU_DIR_DL;
+		rc = osmo_trau_frame_encode(msgb_data(msg), 2*40*8, &fr);
+		OSMO_ASSERT(rc >= 0);
+		msgb_put(msg, rc);
+		osmo_i460_mux_enqueue(peer->i460_sc, msg);
 	} else {
 		/* Convert to RTP */
-		if (fr.type != OSMO_TRAU16_FT_FR && fr.type != OSMO_TRAU16_FT_EFR)
+		if (fr.type != OSMO_TRAU16_FT_FR &&
+		    fr.type != OSMO_TRAU16_FT_EFR &&
+		    fr.type != OSMO_TRAU16_FT_AMR)
 			goto skip;
 
 		uint8_t rtpbuf[35];
diff --git a/include/osmocom/trau/trau_rtp.h b/include/osmocom/trau/trau_rtp.h
index f02d43e..33a6705 100644
--- a/include/osmocom/trau/trau_rtp.h
+++ b/include/osmocom/trau/trau_rtp.h
@@ -24,6 +24,11 @@
 
 struct osmo_trau2rtp_state {
 	enum osmo_trau_frame_type type;
+	struct {
+		enum osmo_amr_type last_cmi;
+		enum osmo_amr_type last_cmr;
+		bool cmi_cmr_phase;
+	} amr;
 };
 
 
diff --git a/src/trau/trau_rtp_conv.c b/src/trau/trau_rtp_conv.c
index ebbdbef..84b1cad 100644
--- a/src/trau/trau_rtp_conv.c
+++ b/src/trau/trau_rtp_conv.c
@@ -26,6 +26,7 @@
 
 #include <osmocom/core/crc8gen.h>
 #include <osmocom/codec/codec.h>
+#include <osmocom/netif/amr.h>
 
 #include <osmocom/trau/trau_frame.h>
 #include <osmocom/trau/trau_rtp.h>
@@ -489,103 +490,199 @@ static int rtp2trau_efr(struct osmo_trau_frame *tf, const uint8_t *data, size_t
 	return 0;
 }
 
-#if 0
-static inline memcpy_inc(uint8_t *out, const uint8_t *in, size_t len, unsigned int *idx)
+/* memcpy + increment index */
+static inline void memcpy_inc(uint8_t *out, const uint8_t *in, size_t len, unsigned int *idx)
 {
-	memcpy_inc(out, in, len);
+	memcpy(out, in, len);
 	*idx += len;
 }
 
+#define S_FROM_D(sbits, dbits, d_from, d_to, idx)  \
+	memcpy_inc(sbits + idx, dbits + (d_from-1), d_to - (d_from-1), &idx)
+
+/* extract the AMR s-bits (codec parameters) from the TRAU frame D-bits */
 static int amr_speech_extract_sbits(ubit_t *s_bits, const struct osmo_trau_frame *tf,
-				    enum osmo_amr_mode mode)
+				    enum osmo_amr_type mode)
 {
 	unsigned int s_idx = 0;
 
 	switch (mode) {
 	case AMR_4_75:
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 44, 67 - 44, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 67, 92 - 67, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 108 - 95, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 111, 132 - 111, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 135, 148 - 135, &s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  45,  67, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  68,  92, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  96, 108, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 112, 132, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 136, 148, s_idx);
 		break;
 	case AMR_5_15:
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 46, 96 - 46, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 69, 92 - 69, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 114 - 95, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 117, 136 - 117, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 139, 158 - 139, &s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  47,  69, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  70,  92, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  96, 114, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 118, 136, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 140, 158, s_idx);
 		break;
 	case AMR_5_90:
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 41, 67 - 41, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 67, 92 - 67, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 116 - 95, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 119, 144 - 119, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 147, 168 - 147, &s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  42,  67, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  68,  92, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  96, 116, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 120, 144, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 148, 168, s_idx);
 		break;
 	case AMR_6_70:
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 37, 63 - 37, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 63, 92 - 63, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 120 - 95, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 123, 152 - 123, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 155, 180 - 155, &s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  38,  63, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  64,  92, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  96, 120, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 124, 152, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 156, 180, s_idx);
 		break;
 	case AMR_7_40:
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 34, 60 - 34, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 60, 92 - 60, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 124 - 95, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 127, 159 - 127, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 162, 191 - 162, &s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  35,  60, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  61,  92, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  96, 124, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 128, 159, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 163, 191, s_idx);
 		break;
 	case AMR_7_95:
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 31, 58 - 31, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 58, 92 - 58, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 127 - 95, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 130, 164 - 130, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 167, 199 - 167, &s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  32,  58, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  59,  92, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  96, 127, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 131, 164, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 168, 199, s_idx);
 		break;
 	case AMR_10_2:
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 20, 46 - 20, &s_idx);	/* D21..D46 */
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 46, 92 - 46, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 95, 138 - 95, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 141, 187 - 141, &s_idx);
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 190, 233 - 190, &s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  21,  46, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  47,  92, s_idx);
+		S_FROM_D(s_bits, tf->d_bits,  96, 138, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 142, 187, s_idx);
+		S_FROM_D(s_bits, tf->d_bits, 191, 233, s_idx);
 		break;
 	case AMR_12_2:
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 0, 38 - 0, &s_idx);	/* D1..D38 */
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 38, 91 - 38, &s_idx);	/* D39..D91 */
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 94, 144 - 94, &s_idx);	/* D95..D144 */
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 147, 200 - 147, &s_idx);/* D148..D200 */
-		memcpy_inc(s_bits + s_idx, tf->d_bits + 203, 253 - 203, &s_idx);/* D204..D253 */
+		S_FROM_D(s_bits, tf->d_bits,   1,  38, s_idx);  /* D1..D38 */
+		S_FROM_D(s_bits, tf->d_bits,  39,  91, s_idx);	/* D39..D91 */
+		S_FROM_D(s_bits, tf->d_bits,  95, 144, s_idx);	/* D95..D144 */
+		S_FROM_D(s_bits, tf->d_bits, 148, 200, s_idx);	/* D148..D200 */
+		S_FROM_D(s_bits, tf->d_bits, 204, 253, s_idx);	/* D204..D253 */
+		break;
+	default:
+		osmo_panic("unknown AMR speech mode: %u", mode);
 		break;
 	}
 
 	return s_idx;
 }
 
+#define D_FROM_S(dbits, sbits, d_from, d_to, idx)  \
+	memcpy_inc(dbits + (d_from-1), sbits + idx, d_to - (d_from-1), &idx)
+
+/* encode the AMR TRAU frame D-bits from the s-bits (codec parameters) */
+static int amr_speech_encode_sbits(struct osmo_trau_frame *tf, const ubit_t *s_bits, enum osmo_amr_type mode)
+{
+	unsigned int s_idx = 0;
+
+	switch (mode) {
+	case AMR_4_75:
+		D_FROM_S(tf->d_bits, s_bits,  45,  67, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  68,  92, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  96, 108, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 112, 132, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 136, 148, s_idx);
+		break;
+	case AMR_5_15:
+		D_FROM_S(tf->d_bits, s_bits,  47,  69, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  70,  92, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  96, 114, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 118, 136, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 140, 158, s_idx);
+		break;
+	case AMR_5_90:
+		D_FROM_S(tf->d_bits, s_bits,  42,  67, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  68,  92, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  96, 116, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 124, 152, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 156, 180, s_idx);
+		break;
+	case AMR_6_70:
+		D_FROM_S(tf->d_bits, s_bits,  38,  63, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  64,  92, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  96, 120, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 124, 152, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 156, 180, s_idx);
+		break;
+	case AMR_7_40:
+		D_FROM_S(tf->d_bits, s_bits,  35,  60, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  61,  92, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  96, 124, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 128, 159, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 163, 191, s_idx);
+		break;
+	case AMR_7_95:
+		D_FROM_S(tf->d_bits, s_bits,  32,  58, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  59,  92, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  96, 127, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 131, 164, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 168, 199, s_idx);
+		break;
+	case AMR_10_2:
+		D_FROM_S(tf->d_bits, s_bits,  21,  46, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  47,  92, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  96, 138, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 142, 187, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 191, 233, s_idx);
+		break;
+	case AMR_12_2:
+		D_FROM_S(tf->d_bits, s_bits,   1,  38, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  39,  91, s_idx);
+		D_FROM_S(tf->d_bits, s_bits,  95, 144, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 148, 200, s_idx);
+		D_FROM_S(tf->d_bits, s_bits, 204, 253, s_idx);
+	default:
+		osmo_panic("unknown AMR speech mode: %u", mode);
+		break;
+	}
+}
+
+/* Frame_Classification as per TS 48.060 Section 5.5.1.2.1 */
+enum amr_frame_class {
+	AMR_FCLS_SPEECH_GOOD		= 3,
+	AMR_FCLS_SPEECH_DEGRADED	= 2,
+	AMR_FCLS_SPEECH_BAD		= 1,
+	AMR_FCLS_NO_SPEECH		= 0,
+};
+
 /* TS 48.060 Section 5.5.1.2.2 */
-static int trau2rtp_16(uint8_t *out, const struct osmo_trau_frame *tf, enum osmo_amr_mode last_cmi)
+static int trau2rtp_16(uint8_t *out, const struct osmo_trau_frame *tf, struct osmo_trau2rtp_state *st)
 {
-	enum osmo_amr_mode mode = last_cmi;
-	uint8_t frame_class = tf->c_bits[21] << 1 | tf->c_bits[20];
-	uint8_t cmr_cmi = tf->c_bits[23] << 2 | tf->c_bits[24] << 1 | tf->cb_bits[25];
+	uint8_t frame_class = (tf->c_bits[21-1] << 1) | tf->c_bits[20-1];
+	uint8_t cmr_cmi = (tf->c_bits[23-1] << 2) | (tf->c_bits[24-1] << 1) | tf->c_bits[25-1];
+	ubit_t rif = tf->c_bits[12-1]; /* Request (1) or Indication (0) Flag */
+	uint8_t tac_pac = (tf->c_bits[6-1] << 5) | (tf->c_bits[7-1] << 4) | (tf->c_bits[8-1] << 3) |
+			  (tf->c_bits[9-1] << 2) | (tf->c_bits[10-1] << 1) | tf->c_bits[11-1];
 	uint8_t no_speech_cls;
-	uint8_t s_bits[242];
-	uint8_t d_bits[242];
-	unsigned int s_idx = 0;
-	ubit_t rif = FIXME;
+	uint8_t s_bits[244];
+	uint8_t d_bits[244];
+	bool bad_frame = false;
+	int n_sbits = 0;
 
 	if (tf->type != OSMO_TRAU16_FT_AMR)
 		return -EINVAL;
 
-	if (rif == 0)
-		mode = cmr_cmi;
+	if (rif == 0) {
+		/* peer (BTS) tells us CMI */
+		st->amr.last_cmi = cmr_cmi;
+	} else {
+		/* peer (BTS) tells us CMR */
+		st->amr.last_cmr = cmr_cmi;
+	}
+
+	if (tac_pac == 0x3d) {
+		/* FIXME: BTS requests us to invert CMI/CMR phase in downlink */
+	}
 
 	switch (frame_class) {
-	case 0: // no speech
-		no_speech_cls = tf->d_bits[32] << 2 | tf->d_bits[33] << 1 | tf->d_bits[34];
-		cmi_abs = tf->d_bits[35] << 2 | tf->d_bits[36] < 1 || tf->d_bits[37];
-		cmr_abs = tf->d_bits[38] << 2 | tf->d_bits[39] < 1 || tf->d_bits[40];
+	case AMR_FCLS_NO_SPEECH:
+		no_speech_cls = (tf->d_bits[32-1] << 2) | (tf->d_bits[33-1] << 1) | tf->d_bits[34-1];
+		st->amr.last_cmi = (tf->d_bits[35-1] << 2) | (tf->d_bits[36-1] < 1) || tf->d_bits[37-1];
+		st->amr.last_cmr = (tf->d_bits[38-1] << 2) | (tf->d_bits[39-1] < 1) || tf->d_bits[40-1];
 		switch (no_speech_cls) {
 		case 7: // sid first
 			break;
@@ -597,25 +694,89 @@ static int trau2rtp_16(uint8_t *out, const struct osmo_trau_frame *tf, enum osmo
 			break;
 		case 0: // no_data
 			break;
+		/* TOOD: PAB to be treated as PAC */
+		/* TODO: Time Alignment Extension (TAE) */
 		}
 		break;
-	case 1: // speech bad
+	case AMR_FCLS_SPEECH_BAD:
+		bad_frame = true;
 		break;
-	case 2:
-	case 3:
+	case AMR_FCLS_SPEECH_GOOD:
+	case AMR_FCLS_SPEECH_DEGRADED:
 		/* Extract the s-bits from the TRAU frame */
-		amr_speech_extract_sbits(s_bits, tf, mode);
+		n_sbits = amr_speech_extract_sbits(s_bits, tf, st->amr.last_cmi);
 		/* Convert the s-bits to d-bits */
-		osmo_amr_s_to_d(d_bits, s_bits, mode);
+		osmo_amr_s_to_d(d_bits, s_bits, n_sbits, st->amr.last_cmi);
 		break;
 	}
+
+	/* generate octet-aligned RTP AMR header / RFC4867 */
+	struct amr_hdr *amrh = (struct amr_hdr *) out;
+	amrh->pad1 = 0;
+	amrh->cmr = st->amr.last_cmr;
+	amrh->pad2 = 0;
+	amrh->q = !bad_frame;
+	amrh->ft = st->amr.last_cmi;
+	amrh->f = 0;
+
+	/* return number of bytes generated */
+	return osmo_ubit2pbit(out + sizeof(*amrh), d_bits, n_sbits) + sizeof(*amrh);
+}
+
+static int rtp2trau_amr(struct osmo_trau_frame *tf, const uint8_t *data, size_t data_len,
+			struct osmo_trau2rtp_state *st)
+{
+	struct amr_hdr *amrh = (struct amr_hdr *) data;
+	ubit_t s_bits[244];
+
+	if (data_len < sizeof(*amrh))
+		return -EIO;
+
+	if (data_len > FIXME)
+		data_len = FIXM;
+
+	/* C1..C5: AMR */
+	tf->c_bits[1-1] = 0;
+	tf->c_bits[2-1] = 0;
+	tf->c_bits[3-1] = 1;
+	tf->c_bits[4-1] = 1;
+	tf->c_bits[5-1] = 0;
+
+	/* C6..C11: TAF: TAC / PAC */
+	memset(&tf->c_bits[6-1], 0, 6);
+
+
+	//tf->c_bits[12-1] = ; /* RIF */
+	tf->c_bits[13-1] = 1; /* UFE */
+	memset(&tf->c_bits[14-1], 0, 3); /* Config_Prot */
+	memset(&tf->c_bits[17-1], 0, 3); /* Message_No */
+	tf->c_bits[19-1] = 1; /* spare */
+	tf->c_bits[20-1] = 1; /* spare */
+
+#if 0
+	tf->c_bits[21-1]
+	tf->c_bits[22-1]
+
+	/* CMI (RIF=0) or CMR (RIF=1) */
+	tf->c_bits[23-1]
+	tf->c_bits[24-1]
+	tf->c_bits[25-1]
+#endif
+
+	/* TODO: convert s-bits to d-bits */
+	osmo_pbit2ubit(s_bits, data + sizeof(*amrh), data_len-sizeof(*amrh));
+	amr_speech_encode_sbits(tf, s_bits, mode)
+
+	/* TODO: compute CRC */
+
+	return 0;
 }
 
-int trau2rtp_amr(uint8_t *out, const struct osmo_trau_frame *tf, enum osmo_amr_mode last_cmi))
+int trau2rtp_amr(uint8_t *out, size_t out_len, const struct osmo_trau_frame *tf, struct osmo_trau2rtp_state *st)
 {
 	switch (tf->type) {
 	case OSMO_TRAU16_FT_AMR:
-		return trau2rtp_16(out, tf, last_cmi);
+		return trau2rtp_16(out, tf, st);
 	case OSMO_TRAU8_AMR_LOW:
 	case OSMO_TRAU8_AMR_6k7:
 	case OSMO_TRAU8_AMR_7k4:
@@ -623,7 +784,6 @@ int trau2rtp_amr(uint8_t *out, const struct osmo_trau_frame *tf, enum osmo_amr_m
 		return -EINVAL;
 	}
 }
-#endif
 
 int osmo_trau2rtp(uint8_t *out, size_t out_len, const struct osmo_trau_frame *tf,
 		  struct osmo_trau2rtp_state *st)
@@ -635,6 +795,8 @@ int osmo_trau2rtp(uint8_t *out, size_t out_len, const struct osmo_trau_frame *tf
 		return trau2rtp_efr(out, out_len, tf);
 	case OSMO_TRAU16_FT_HR:
 		return trau2rtp_hr16(out, out_len, tf);
+	case OSMO_TRAU16_FT_AMR:
+		return trau2rtp_amr(out, out_len, tf, st);
 	default:
 		return -EINVAL;
 	}
@@ -650,6 +812,8 @@ int osmo_rtp2trau(struct osmo_trau_frame *tf, const uint8_t *rtp, size_t rtp_len
 		return rtp2trau_efr(tf, rtp, rtp_len);
 	case OSMO_TRAU16_FT_HR:
 		return rtp2trau_hr16(tf, rtp, rtp_len);
+	case OSMO_TRAU16_FT_AMR:
+		//return rtp2trau_amr(tf, rtp, rtp_len, st);
 	default:
 		return -EINVAL;
 	}