add some utility functions for paging related calculation (TS 05.02)

[osmocom-bb.git] / src / gsm / gsm48.c

diff --git a/src/gsm/gsm48.c b/src/gsm/gsm48.c
index 4645af4..44baec6 100644 (file)
--- a/src/gsm/gsm48.c
+++ b/src/gsm/gsm48.c
@@ -31,6 +31,7 @@
 #include <osmocom/core/utils.h>
 #include <osmocom/gsm/tlv.h>
 #include <osmocom/gsm/gsm48.h>
+#include <osmocom/gsm/gsm0502.h>
 
 #include <osmocom/gsm/protocol/gsm_04_08.h>
 #include <osmocom/gsm/protocol/gsm_08_58.h>
@@ -418,11 +419,10 @@ int gsm48_construct_ra(uint8_t *buf, const struct gprs_ra_id *raid)
 /* From Table 10.5.33 of GSM 04.08 */
 int gsm48_number_of_paging_subchannels(struct gsm48_control_channel_descr *chan_desc)
 {
-       if (chan_desc->ccch_conf == RSL_BCCH_CCCH_CONF_1_C) {
-               return OSMO_MAX(1, (3 - chan_desc->bs_ag_blks_res))
-                       * (chan_desc->bs_pa_mfrms + 2);
-       } else {
-               return (9 - chan_desc->bs_ag_blks_res)
-                       * (chan_desc->bs_pa_mfrms + 2);
-       }
+       unsigned int n_pag_blocks = gsm0502_get_n_pag_blocks(chan_desc);
+
+       if (chan_desc->ccch_conf == RSL_BCCH_CCCH_CONF_1_C)
+               return OSMO_MAX(1, n_pag_blocks) * (chan_desc->bs_pa_mfrms + 2);
+       else
+               return n_pag_blocks * (chan_desc->bs_pa_mfrms + 2);
 }