bssmap: State correct speech codec in ASSIGNMENT COMPLETE

Correctly compute the TS 48.008 "speech mode" (codec) for AMR on TCH/F.

There are way too many different ways how to express a given voice
codec.  There are two different schemes in TS 48.008 alone, plus one
on TS 48.058 and one in 04.08 / 44.018.  Let's avoid unneeded
conversion (that we might get wrong) and avoid storing information in
a sub-struct of the lchan if we can simply derive it from the lchan
at the time we need it.

Also, move BSSAP related encoding/conversion functions closer to the
user (osmo_bsc_bssap), rather than in libbsc.

Without this patch, TCH/F with AMR was erroneously reported as TCH/H
with AMR in the BSSMAP ASSIGNMENT COMPLETE.  After this patch, it's
reported correctly.

Change-Id: I6feebfae77fdc93a7ce333a25dd9b9267c5a4a2e
Related: OS#3094
Related: OS#3095
Related: OS#3096

1 files changed, 2 insertions, 91 deletions

diff --git a/src/libbsc/bsc_api.c b/src/libbsc/bsc_api.c
index 748245342..142efef02 100644
--- a/src/libbsc/bsc_api.c
+++ b/src/libbsc/bsc_api.c
@@ -50,89 +50,6 @@ static void handle_release(struct gsm_subscriber_connection *conn, struct bsc_ap
 static void handle_chan_ack(struct gsm_subscriber_connection *conn, struct bsc_api *bsc, struct  gsm_lchan *lchan);
 static void handle_chan_nack(struct gsm_subscriber_connection *conn, struct bsc_api *bsc, struct  gsm_lchan *lchan);
 
-/* GSM 08.08 3.2.2.33 */
-uint8_t lchan_to_chosen_channel(struct gsm_lchan *lchan)
-{
-	uint8_t channel_mode = 0, channel = 0;
-
-	switch (lchan->tch_mode) {
-	case GSM48_CMODE_SPEECH_V1:
-	case GSM48_CMODE_SPEECH_EFR:
-	case GSM48_CMODE_SPEECH_AMR:
-		channel_mode = 0x9;
-		break;
-	case GSM48_CMODE_SIGN:
-		channel_mode = 0x8;
-		break;
-	case GSM48_CMODE_DATA_14k5:
-		channel_mode = 0xe;
-		break;
-	case GSM48_CMODE_DATA_12k0:
-		channel_mode = 0xb;
-		break;
-	case GSM48_CMODE_DATA_6k0:
-		channel_mode = 0xc;
-		break;
-	case GSM48_CMODE_DATA_3k6:
-		channel_mode = 0xd;
-		break;
-	}
-
-	switch (lchan->type) {
-	case GSM_LCHAN_NONE:
-		channel = 0x0;
-		break;
-	case GSM_LCHAN_SDCCH:
-		channel = 0x1;
-		break;
-	case GSM_LCHAN_TCH_F:
-		channel = 0x8;
-		break;
-	case GSM_LCHAN_TCH_H:
-		channel = 0x9;
-		break;
-	case GSM_LCHAN_UNKNOWN:
-	default:
-		LOGP(DMSC, LOGL_ERROR, "Unknown lchan type: %p\n", lchan);
-		break;
-	}
-
-	return channel_mode << 4 | channel;
-}
-
-uint8_t chan_mode_to_speech(struct gsm_lchan *lchan)
-{
-	int mode = 0;
-
-	switch (lchan->tch_mode) {
-	case GSM48_CMODE_SPEECH_V1:
-		mode = 1;
-		break;
-	case GSM48_CMODE_SPEECH_EFR:
-		mode = 0x11;
-		break;
-	case GSM48_CMODE_SPEECH_AMR:
-		mode = 0x21;
-		break;
-	case GSM48_CMODE_SIGN:
-	case GSM48_CMODE_DATA_14k5:
-	case GSM48_CMODE_DATA_12k0:
-	case GSM48_CMODE_DATA_6k0:
-	case GSM48_CMODE_DATA_3k6:
-	default:
-		LOGP(DMSC, LOGL_ERROR, "Using non speech mode: %d\n", mode);
-		return 0;
-		break;
-	}
-
-	/* assume to always do AMR HR on any TCH type */
-	if (lchan->type == GSM_LCHAN_TCH_H ||
-	    lchan->tch_mode == GSM48_CMODE_SPEECH_AMR)
-		mode |= 0x4;
-
-        return mode;
-}
-
 /*! \brief Determine and apply AMR multi-rate configuration to lchan
  *  Determine which AMR multi-rate configuration to use and apply it to
  *  the lchan (so it can be communicated to BTS and MS during channel
@@ -470,10 +387,7 @@ static void handle_ass_compl(struct gsm_subscriber_connection *conn,
 	if (is_ipaccess_bts(conn_get_bts(conn)) && conn->lchan->tch_mode != GSM48_CMODE_SIGN)
 		rsl_ipacc_crcx(conn->lchan);
 
-	api->assign_compl(conn, gh->data[0],
-			  lchan_to_chosen_channel(conn->lchan),
-			  conn->lchan->encr.alg_id,
-			  chan_mode_to_speech(conn->lchan));
+	api->assign_compl(conn, gh->data[0]);
 }
 
 static void handle_ass_fail(struct gsm_subscriber_connection *conn,
@@ -673,10 +587,7 @@ static void dispatch_dtap(struct gsm_subscriber_connection *conn,
 						 GSM0808_CAUSE_NO_RADIO_RESOURCE_AVAILABLE,
 						 NULL);
 			} else if (rc >= 0) {
-				api->assign_compl(conn, 0,
-						  lchan_to_chosen_channel(conn->lchan),
-						  conn->lchan->encr.alg_id,
-						  chan_mode_to_speech(conn->lchan));
+				api->assign_compl(conn, 0);
 			}
 			break;
 		case GSM48_MT_RR_CLSM_CHG: