Set DTX in Cell Options
* rename field of struct gsm48_cell_options to better match the spec
* add comments with spec references
* add function for setting DTX in cell options struct
* add necessary enum type
Change-Id: I5a8924f57669c951b2e51b663d95f1d360062a54
Reviewed-on: https://gerrit.osmocom.org/39
Reviewed-by: Harald Welte <laforge@gnumonks.org>
Tested-by: Jenkins Builder
diff --git a/src/gsm/gsm48.c b/src/gsm/gsm48.c
index ab62605..8a46f76 100644
--- a/src/gsm/gsm48.c
+++ b/src/gsm/gsm48.c
@@ -25,7 +25,7 @@
#include <stdint.h>
#include <stdio.h>
#include <string.h>
-
+#include <stdbool.h>
#include <arpa/inet.h>
#include <osmocom/core/utils.h>
@@ -358,6 +358,50 @@
return 0;
}
+/*! \brief Set DTX mode in Cell Options IE (3GPP TS 44.018)
+ * \param[in] op Cell Options structure in which DTX parameters will be set
+ * \param[in] full Mode for full-rate channels
+ * \param[in] half Mode for half-rate channels
+ * \param[in] is_bcch Indicates if we should use 10.5.2.3.1 instead of
+ * 10.5.2.3a.2
+ *
+ * There is no space for separate DTX settings for Full and Half rate channels
+ * in BCCH - in this case full setting is used for both and half parameter is
+ * ignored.
+ */
+void gsm48_set_dtx(struct gsm48_cell_options *op, enum gsm48_dtx_mode full,
+ enum gsm48_dtx_mode half, bool is_bcch)
+{
+ if (is_bcch) {
+ switch (full) {
+ case GSM48_DTX_MAY_BE_USED:
+ op->dtx = 0;
+ return;
+ case GSM48_DTX_SHALL_BE_USED:
+ op->dtx = 1;
+ return;
+ case GSM48_DTX_SHALL_NOT_BE_USED:
+ op->dtx = 2;
+ return;
+ }
+ } else {
+ switch (full) {
+ case GSM48_DTX_MAY_BE_USED:
+ op->dtx = (half == GSM48_DTX_SHALL_BE_USED) ? 3 : 0;
+ op->d = (half == GSM48_DTX_SHALL_NOT_BE_USED) ? 0 : 1;
+ return;
+ case GSM48_DTX_SHALL_BE_USED:
+ op->dtx = (half == GSM48_DTX_MAY_BE_USED) ? 3 : 1;
+ op->d = (half == GSM48_DTX_SHALL_BE_USED) ? 1 : 0;
+ return;
+ case GSM48_DTX_SHALL_NOT_BE_USED:
+ op->dtx = 2;
+ op->d = (half == GSM48_DTX_SHALL_BE_USED) ? 1 : 0;
+ return;
+ }
+ }
+}
+
int gsm48_generate_mid_from_tmsi(uint8_t *buf, uint32_t tmsi)
{
uint32_t tmsi_be = htonl(tmsi);
diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map
index e0d9dcb..834e5d6 100644
--- a/src/gsm/libosmogsm.map
+++ b/src/gsm/libosmogsm.map
@@ -162,6 +162,8 @@
gsm48_number_of_paging_subchannels;
gsm48_parse_ra;
gsm48_rr_att_tlvdef;
+gsm48_set_dtx;
+gsm48_dtx_mode;
gsm48_mi_type_name;
gsm48_mcc_mnc_to_bcd;
gsm48_mcc_mnc_from_bcd;