[gsm48] Add generation of ASSIGNMENT COMMAND to the 0408 utils
Add code to generate an assignment command for a given lchan. It
is expected that the lchan is modified already and the mode will
be picked up from their. Currently only the mandantory items
are supported.
diff --git a/openbsc/src/gsm_04_08_utils.c b/openbsc/src/gsm_04_08_utils.c
index ef9e59c..358212f 100644
--- a/openbsc/src/gsm_04_08_utils.c
+++ b/openbsc/src/gsm_04_08_utils.c
@@ -482,3 +482,35 @@
return rsl_encryption_cmd(msg);
}
+/* Chapter 9.1.2: Assignment Command */
+int gsm48_send_rr_ass_cmd(struct gsm_lchan *lchan, u_int8_t power_command)
+{
+ struct msgb *msg = gsm48_msgb_alloc();
+ struct gsm48_hdr *gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh));
+ struct gsm48_ass_cmd *ass =
+ (struct gsm48_ass_cmd *) msgb_put(msg, sizeof(*ass));
+ u_int16_t arfcn = lchan->ts->trx->arfcn & 0x3ff;
+
+ DEBUGP(DRR, "-> ASSIGNMENT COMMAND tch_mode=0x%02x\n", lchan->tch_mode);
+
+ msg->lchan = lchan;
+ gh->proto_discr = GSM48_PDISC_RR;
+ gh->msg_type = GSM48_MT_RR_ASS_CMD;
+
+ /*
+ * fill the channel information element, this code
+ * should probably be shared with rsl_rx_chan_rqd(),
+ * gsm48_tx_chan_mode_modify. But beware that 10.5.2.5
+ * 10.5.2.5.a have slightly different semantic for
+ * the chan_desc. But as long as multi-slot configurations
+ * are not used we seem to be fine.
+ */
+ ass->chan_desc.chan_nr = lchan2chan_nr(lchan);
+ ass->chan_desc.h0.tsc = lchan->ts->trx->bts->tsc;
+ ass->chan_desc.h0.h = 0;
+ ass->chan_desc.h0.arfcn_high = arfcn >> 8;
+ ass->chan_desc.h0.arfcn_low = arfcn & 0xff;
+ ass->power_command = power_command;
+
+ return gsm48_sendmsg(msg, NULL);
+}