laforge submitted this change.
ASCI: Add group transmit mode support to RR layer
This allows the upper layer to estabish and release connection on the
uplink of a voice group call.
Related: OS#5364
Change-Id: I9b62eef5d877e5d9dcf349717efd2cce28862c58
---
M src/host/layer23/include/osmocom/bb/common/settings.h
M src/host/layer23/include/osmocom/bb/mobile/gsm48_rr.h
M src/host/layer23/src/mobile/gsm48_rr.c
3 files changed, 743 insertions(+), 65 deletions(-)
diff --git a/src/host/layer23/include/osmocom/bb/common/settings.h b/src/host/layer23/include/osmocom/bb/common/settings.h
index c5469c1..884578b 100644
--- a/src/host/layer23/include/osmocom/bb/common/settings.h
+++ b/src/host/layer23/include/osmocom/bb/common/settings.h
@@ -188,6 +188,9 @@
/* Timeout for GSM 03.22 C7 state */
uint8_t any_timeout;
+
+ /* ASCI settings */
+ bool uplink_release_local;
};
struct gsm_settings_abbrev {
diff --git a/src/host/layer23/include/osmocom/bb/mobile/gsm48_rr.h b/src/host/layer23/include/osmocom/bb/mobile/gsm48_rr.h
index 1429fd3..16f7fb3 100644
--- a/src/host/layer23/include/osmocom/bb/mobile/gsm48_rr.h
+++ b/src/host/layer23/include/osmocom/bb/mobile/gsm48_rr.h
@@ -10,6 +10,9 @@
#define T200_DCCH_SHARED 2 /* SDCCH shares SAPI 0 and 3 */
#define T200_ACCH 2 /* SACCH SAPI 3 */
+/* GSM 04.08 RR timers */
+#define GSM_T3128_MS 1, 0 /* Uplink investigation timer. */
+#define GSM_T3130_MS 5, 0 /* Uplink access timeout. */
/* GSM 04.07 9.1.2 */
@@ -221,6 +224,14 @@
struct llist_head notif_list; /* list of received call notifications */
enum gsm48_rr_gstate group_state; /* extension to RR state for group transmit/receive modes */
struct gsm48_rr_cd cd_group; /* channel description of group call channel */
+ bool uplink_free; /* Is set, if uplink is currently free. */
+ uint8_t uic; /* UIC to use for access burst (-1 for BSIC) */
+ bool uplink_access; /* The network wants us to send listener access bursts. */
+ struct osmo_timer_list t_ul_free; /* Uplink free timer. (480ms timer) */
+ struct osmo_timer_list t3128; /* Uplink investigation timer. */
+ struct osmo_timer_list t3130; /* Uplink access timer. */
+ uint8_t uplink_tries; /* Counts number of tries to access the uplink. */
+ uint8_t uplink_counter; /* Counts number of access bursts per 'try'. */
} vgcs;
};
diff --git a/src/host/layer23/src/mobile/gsm48_rr.c b/src/host/layer23/src/mobile/gsm48_rr.c
index c78993b..a515338 100644
--- a/src/host/layer23/src/mobile/gsm48_rr.c
+++ b/src/host/layer23/src/mobile/gsm48_rr.c
@@ -50,6 +50,22 @@
* new_rr_state(rr, GSM48_RR_ST_IDLE) is used to return to IDLE mode or to
* group receive mode, depending on the substate.
*
+ * The Uplink access on group channel:
+ *
+ * If the uplink is busy, wait until it becomes free (Uplink investigation
+ * procedure). Abort, if the procedure times out, if the VGCS UPLINK GRANT
+ * message is recived for a different talker.
+ *
+ * Request uplink using access bursts on TCH until an VGCS UPLINK GRANT is
+ * received. Abort, if it the procedure times out, if the uplink becomes busy,
+ * if the VGCS UPLINK GRANT message references a different frame numer.
+ *
+ * Establish layer 2 with TALKER INDICATION. Abort, if content resolution
+ * mismatches (RR_REL_IND), if link fails (MDL_ERROR), if uplink becomes free.
+ *
+ * Release uplink and wait until uplink becomes free. Abort, if UPLINK RELEASE
+ * is received or if uplink fails.
+ *
* New primitives are invented for group/broadcast calls. They are not
* specified in any recommendation. They are:
*
@@ -132,6 +148,13 @@
static int gsm48_rr_rel_cnf(struct osmocom_ms *ms, struct msgb *msg);
int gsm414_rcv_test(struct osmocom_ms *ms, const struct msgb *msg);
static int gsm48_rr_group_rel(struct osmocom_ms *ms, int cause);
+static int gsm48_rr_uplink_access(struct osmocom_ms *ms, struct msgb *msg);
+static int gsm48_rr_uplink_access_abort(struct osmocom_ms *ms, uint8_t cause);
+static int gsm48_rr_uplink_status(struct osmocom_ms *ms, uint32_t event);
+static int gsm48_match_ra(struct osmocom_ms *ms, struct gsm48_req_ref *ref, uint8_t hist_num);
+static int gsm48_rr_tx_talker_indication(struct osmocom_ms *ms);
+static int gsm48_rr_tx_rand_acc_dedicated(struct osmocom_ms *ms, uint8_t ref, uint16_t offset, int8_t uic);
+static int gsm48_rr_uplink_rel_req(struct osmocom_ms *ms, struct msgb *msg);
/*
* support
@@ -871,6 +894,36 @@
new_rr_state(rr, GSM48_RR_ST_IDLE);
}
+static void timeout_rr_t3128(void *arg)
+{
+ struct gsm48_rrlayer *rr = arg;
+ struct osmocom_ms *ms = rr->ms;
+
+ LOGP(DRR, LOGL_INFO, "timer T3128 has fired\n");
+
+ LOGP(DRR, LOGL_NOTICE, "Failed to access uplink, uplink did not become free.\n");
+ gsm48_rr_uplink_access_abort(ms, RR_REL_CAUSE_UPLINK_BUSY);
+}
+
+static void timeout_rr_t3130(void *arg)
+{
+ struct gsm48_rrlayer *rr = arg;
+ struct osmocom_ms *ms = rr->ms;
+
+ LOGP(DRR, LOGL_INFO, "timer T3130 has fired\n");
+
+ gsm48_rr_uplink_access(ms, NULL);
+}
+
+static void timeout_rr_t_ul_free(void *arg)
+{
+ struct gsm48_rrlayer *rr = arg;
+
+ LOGP(DRR, LOGL_INFO, "uplink free timer has fired\n");
+ rr->vgcs.uplink_free = false;
+ gsm48_rr_uplink_status(rr->ms, GSM48_MM_EVENT_UPLINK_BUSY);
+}
+
static void start_rr_t_meas(struct gsm48_rrlayer *rr, int sec, int micro)
{
rr->t_meas.cb = timeout_rr_meas;
@@ -923,6 +976,33 @@
osmo_timer_schedule(&rr->t3126, sec, micro);
}
+static void start_rr_t3128(struct gsm48_rrlayer *rr, int sec, int micro)
+{
+ LOGP(DRR, LOGL_INFO, "starting T3128 with %d.%03d seconds\n", sec,
+ micro / 1000);
+ rr->vgcs.t3128.cb = timeout_rr_t3128;
+ rr->vgcs.t3128.data = rr;
+ osmo_timer_schedule(&rr->vgcs.t3128, sec, micro);
+}
+
+static void start_rr_t3130(struct gsm48_rrlayer *rr, int sec, int micro)
+{
+ LOGP(DRR, LOGL_INFO, "starting T3130 with %d.%03d seconds\n", sec,
+ micro / 1000);
+ rr->vgcs.t3130.cb = timeout_rr_t3130;
+ rr->vgcs.t3130.data = rr;
+ osmo_timer_schedule(&rr->vgcs.t3130, sec, micro);
+}
+
+static void start_rr_t_ul_free(struct gsm48_rrlayer *rr)
+{
+ if (!osmo_timer_pending(&rr->vgcs.t_ul_free))
+ LOGP(DRR, LOGL_INFO, "starting uplink free timer\n");
+ rr->vgcs.t_ul_free.cb = timeout_rr_t_ul_free;
+ rr->vgcs.t_ul_free.data = rr;
+ osmo_timer_schedule(&rr->vgcs.t_ul_free, 0, 480000);
+}
+
static void stop_rr_t_meas(struct gsm48_rrlayer *rr)
{
if (osmo_timer_pending(&rr->t_meas)) {
@@ -979,6 +1059,30 @@
}
}
+static void stop_rr_t3128(struct gsm48_rrlayer *rr)
+{
+ if (osmo_timer_pending(&rr->vgcs.t3128)) {
+ LOGP(DRR, LOGL_INFO, "stopping pending timer T3128\n");
+ osmo_timer_del(&rr->vgcs.t3128);
+ }
+}
+
+static void stop_rr_t3130(struct gsm48_rrlayer *rr)
+{
+ if (osmo_timer_pending(&rr->vgcs.t3130)) {
+ LOGP(DRR, LOGL_INFO, "stopping pending timer T3130\n");
+ osmo_timer_del(&rr->vgcs.t3130);
+ }
+}
+
+static void stop_rr_t_ul_free(struct gsm48_rrlayer *rr)
+{
+ if (osmo_timer_pending(&rr->vgcs.t_ul_free)) {
+ LOGP(DRR, LOGL_INFO, "stopping pending uplink free timer\n");
+ osmo_timer_del(&rr->vgcs.t_ul_free);
+ }
+}
+
/*
* status
*/
@@ -1612,6 +1716,401 @@
}
/*
+ * VGCS uplink control
+ */
+
+/* Send uplink status to upper layer. */
+static int gsm48_rr_uplink_status(struct osmocom_ms *ms, uint32_t event)
+{
+ struct gsm48_rrlayer *rr = &ms->rrlayer;
+ struct msgb *nmsg;
+
+ if (rr->vgcs.group_state != GSM48_RR_GST_RECEIVE)
+ return -EINVAL;
+
+ /* Send notification of uplink state to MM layer. */
+ LOGP(DRR, LOGL_INFO, "Notify MM layer about uplink state.\n");
+ nmsg = gsm48_mmevent_msgb_alloc(event);
+ if (!nmsg)
+ return -ENOMEM;
+ gsm48_mmevent_msg(rr->ms, nmsg);
+
+ return 0;
+}
+
+/* UPLINK BUSY (9.1.46) */
+static int gsm48_rr_rx_uplink_busy(struct osmocom_ms *ms, struct msgb *msg)
+{
+ struct gsm48_rrlayer *rr = &ms->rrlayer;
+
+ LOGP(DRR, LOGL_INFO, "UPLINK BUSY\n");
+
+ /* Only allow when in some group mode. */
+ if (rr->vgcs.group_state == GSM48_RR_GST_OFF)
+ return 0;
+
+ /* Uplink is busy now. */
+ if (rr->vgcs.uplink_free) {
+ rr->vgcs.uplink_free = false;
+ gsm48_rr_uplink_status(ms, GSM48_MM_EVENT_UPLINK_BUSY);
+ }
+ stop_rr_t_ul_free(rr);
+
+ /* Abort during uplink investigation or access procedure. */
+ if (osmo_timer_pending(&rr->vgcs.t3128) || osmo_timer_pending(&rr->vgcs.t3130)) {
+ LOGP(DRR, LOGL_NOTICE, "Abort uplink access, due to busy uplink.\n");
+ return gsm48_rr_uplink_access_abort(ms, RR_REL_CAUSE_UPLINK_BUSY);
+ }
+
+ return 0;
+}
+
+/* UPLINK FREE (9.1.47) */
+static int gsm48_rr_rx_uplink_free(struct osmocom_ms *ms, struct msgb *msg)
+{
+ struct gsm48_rrlayer *rr = &ms->rrlayer;
+ struct bitvec bv;
+ bool uplink_access = false;
+ uint8_t uic = 0xff;
+ uint8_t *mode;
+
+ bv = (struct bitvec) {
+ .data_len = msgb_l3len(msg),
+ .data = msgb_l3(msg),
+ .cur_bit = 8,
+ };
+
+ /* Uplink Access */
+ if (bitvec_get_bit_high(&bv) == H)
+ uplink_access = true;
+
+ /* UIC */
+ if (bitvec_get_bit_high(&bv) == H)
+ uic = bitvec_get_uint(&bv, 6);
+
+ /* Note: Emergency Indicator not used. */
+
+ /* Do not flood the logging with UPLINK FREE messages. Log only on the fist received message. */
+ if (!osmo_timer_pending(&rr->vgcs.t_ul_free))
+ LOGP(DRR, LOGL_INFO, "UPLINK FREE (uplink access=%s, uic=0x%02x)\n", (uplink_access) ? "true" : "false",
+ uic);
+
+ /* Uplink is free now. */
+ if (!rr->vgcs.uplink_free) {
+ rr->vgcs.uplink_free = true;
+ gsm48_rr_uplink_status(ms, GSM48_MM_EVENT_UPLINK_FREE);
+ }
+ rr->vgcs.uic = uic;
+ rr->vgcs.uplink_access = uplink_access;
+ start_rr_t_ul_free(rr);
+
+ /* We can be in group mode or in dedicated mode. When we are in dedicated mode and we receive UPLINK FREE,
+ * we know that we are actually on a group channel. This is the actual confirm to the UPLINK RELEASE message
+ * on a group channel. We must then release layer 2 locally and indicate channel release toward upper layer.
+ *
+ * When we are in group transmit mode, we return to group receive mode and also release layer 2 locally and
+ * indicate uplink release towards upper layer.
+ *
+ * When we are waiting for a free uplink (T3128 is running), we start uplink access. While accessing the
+ * uplink, we ignore further UPLINK FREE messages.
+ */
+ if (rr->vgcs.group_state != GSM48_RR_GST_OFF) {
+ /* Start uplink access. */
+ if (osmo_timer_pending(&rr->vgcs.t3128)) {
+ /* Stop timer, because uplink is now free. */
+ stop_rr_t3128(rr);
+ rr->vgcs.uplink_tries = 3;
+ return gsm48_rr_uplink_access(ms, NULL);
+ }
+
+ /* Ignore uplink free messages while accessing uplink. */
+ if (osmo_timer_pending(&rr->vgcs.t3130))
+ return 0;
+ }
+
+ /* Any time in group transmit mode or dedicated mode, release on uplink free. */
+ if (rr->state == GSM48_RR_ST_DEDICATED || rr->state == GSM48_RR_ST_REL_PEND) {
+ struct msgb *nmsg;
+
+ LOGP(DRR, LOGL_INFO, "Uplink becomes free, send (local) release to layer 2.\n");
+
+ /* Go into pending release state if not already.
+ * We are already in pending relese state when we release uplink normally.
+ * If we receive UPLINK FREE while we release normally, we abort layer 2. */
+ if (rr->state != GSM48_RR_ST_REL_PEND)
+ new_rr_state(rr, GSM48_RR_ST_REL_PEND);
+
+ /* release message */
+ nmsg = gsm48_l3_msgb_alloc();
+ if (!nmsg)
+ return -ENOMEM;
+ mode = msgb_put(nmsg, 2);
+ mode[0] = RSL_IE_RELEASE_MODE;
+ mode[1] = RSL_REL_LOCAL_END;
+ gsm48_send_rsl_nol3(ms, RSL_MT_REL_REQ, nmsg, 0);
+
+ return 0;
+ }
+
+ return 0;
+}
+
+/* UPLINK RELEASE (9.1.48) */
+static int gsm48_rr_rx_uplink_release(struct osmocom_ms *ms, struct msgb *msg)
+{
+ struct gsm48_rrlayer *rr = &ms->rrlayer;
+ struct gsm48_hdr *gh = msgb_l3(msg);
+ struct gsm48_uplink_release *ur = (struct gsm48_uplink_release *)gh->data;
+ int payload_len = msgb_l3len(msg) - sizeof(*gh) - sizeof(*ur);
+
+ if (payload_len < 0) {
+ LOGP(DRR, LOGL_NOTICE, "Short UPLINK RELEASE message.\n");
+ return -EINVAL;
+ }
+
+ LOGP(DRR, LOGL_INFO, "UPLINK RELEASE with cause 0x%02x\n", ur->rr_cause);
+
+ /* Only allow when in some group mode. */
+ if (rr->vgcs.group_state == GSM48_RR_GST_OFF)
+ return 0;
+
+ if (rr->state == GSM48_RR_ST_DEDICATED && rr->vgcs.group_state == GSM48_RR_GST_TRANSMIT)
+ return gsm48_rr_uplink_access_abort(ms, RR_REL_CAUSE_NORMAL);
+
+ return 0;
+}
+
+/* VGCS UPLINK GRANT (9.1.49) */
+static int gsm48_rr_rx_vgcs_uplink_grant(struct osmocom_ms *ms, struct msgb *msg)
+{
+ struct gsm48_rrlayer *rr = &ms->rrlayer;
+ struct gsm48_sysinfo *s = &ms->cellsel.sel_si;
+ struct gsm_settings *set = &ms->settings;
+ struct gsm0408_vgcs_ul_grant *ug = msgb_l3(msg);
+ int ug_len = msgb_l3len(msg) - sizeof(*ug);
+
+ LOGP(DRR, LOGL_INFO, "VGCS UPLINK GRANT\n");
+
+ if (ug_len < 0) {
+ LOGP(DRR, LOGL_NOTICE, "Short read of VGCS UPLINK GRANT message.\n");
+ return -EINVAL;
+ }
+
+ /* Only allow when in some group mode. */
+ if (rr->vgcs.group_state == GSM48_RR_GST_OFF)
+ return 0;
+
+ /* Uplink is busy now. */
+ if (rr->vgcs.uplink_free) {
+ rr->vgcs.uplink_free = false;
+ gsm48_rr_uplink_status(rr->ms, GSM48_MM_EVENT_UPLINK_BUSY);
+ }
+ stop_rr_t_ul_free(rr);
+
+ /* Abort during uplink investigation or access procedure. */
+ if (osmo_timer_pending(&rr->vgcs.t3128)) {
+ LOGP(DRR, LOGL_NOTICE, "Abort uplink access, other phone accessing the uplink.\n");
+ return gsm48_rr_uplink_access_abort(ms, RR_REL_CAUSE_UPLINK_BUSY);
+ }
+
+ /* We are not waiting for the uplink to be granted. */
+ if (!osmo_timer_pending(&rr->vgcs.t3130))
+ return 0;
+
+ /* Stop timer. */
+ stop_rr_t3130(rr);
+
+ /* Check if message is for our request. */
+ if (!gsm48_match_ra(ms, &ug->req_ref, 5)) {
+ LOGP(DRR, LOGL_NOTICE, "Abort uplink access, other phone gets uplink access granted.\n");
+ return gsm48_rr_uplink_access_abort(ms, RR_REL_CAUSE_UPLINK_BUSY);
+ }
+
+ LOGP(DRR, LOGL_INFO, "Access to uplink has been granted.\n");
+
+ /* Set initial power and timing advance. */
+ rr->cd_now.ind_tx_power = s->ms_txpwr_max_cch;
+ rr->cd_now.ind_ta = ug->ta;
+ LOGP(DRR, LOGL_INFO, "Applying initial ta and tx_power\n");
+ l1ctl_tx_param_req(ms, rr->cd_now.ind_ta - set->alter_delay,
+ (set->alter_tx_power) ? set->alter_tx_power_value : s->ms_txpwr_max_cch);
+
+ /* Turn on transmitter. */
+ rr->cd_now.tch_flags &= ~(L1CTL_TCH_FLAG_RXONLY);
+ gsm48_rr_set_mode(ms, rr->cd_now.chan_nr, rr->cd_now.mode, rr->cd_now.tch_flags);
+
+ /* Complete group transmit mode. */
+ new_rr_state(rr, GSM48_RR_ST_DEDICATED);
+
+ /* Establish layer 2 connection. */
+ return gsm48_rr_tx_talker_indication(ms);
+}
+
+/* send rr uplink release */
+static int gsm48_rr_tx_uplink_release(struct osmocom_ms *ms, uint8_t cause)
+{
+ struct msgb *nmsg;
+ struct gsm48_hdr *gh;
+ struct gsm48_uplink_release *ur;
+
+ LOGP(DRR, LOGL_INFO, "UPLINK RELEASE (cause #%d)\n", cause);
+
+ nmsg = gsm48_l3_msgb_alloc();
+ if (!nmsg)
+ return -ENOMEM;
+ gh = (struct gsm48_hdr *) msgb_put(nmsg, sizeof(*gh));
+ ur = (struct gsm48_uplink_release *) msgb_put(nmsg, sizeof(*ur));
+
+ gh->proto_discr = GSM48_PDISC_RR;
+ gh->msg_type = GSM48_MT_RR_UPLINK_RELEASE;
+ ur->rr_cause = cause;
+
+ return gsm48_send_rsl(ms, RSL_MT_DATA_REQ, nmsg, 0);
+}
+
+/* Start uplink access procedure. (3.3.1.2.1.2) */
+static int gsm48_rr_uplink_access(struct osmocom_ms *ms, struct msgb *msg)
+{
+ struct gsm48_rrlayer *rr = &ms->rrlayer;
+
+ /* store frame number */
+ if (msg) {
+ struct abis_rsl_cchan_hdr *ch = msgb_l2(msg);
+ struct gsm48_req_ref *ref =
+ (struct gsm48_req_ref *) (ch->data + 1);
+
+ if (msgb_l2len(msg) < sizeof(*ch) + sizeof(*ref)) {
+ LOGP(DRR, LOGL_ERROR, "CHAN_CNF too slort\n");
+ return -EINVAL;
+ }
+
+ /* Store to history buffer. */
+ /* shift history and store */
+ memcpy(&(rr->cr_hist[4]), &(rr->cr_hist[3]),
+ sizeof(struct gsm48_cr_hist));
+ memcpy(&(rr->cr_hist[3]), &(rr->cr_hist[2]),
+ sizeof(struct gsm48_cr_hist));
+ memcpy(&(rr->cr_hist[2]), &(rr->cr_hist[1]),
+ sizeof(struct gsm48_cr_hist));
+ memcpy(&(rr->cr_hist[1]), &(rr->cr_hist[0]),
+ sizeof(struct gsm48_cr_hist));
+ rr->cr_hist[0].valid = 1;
+ rr->cr_hist[0].ref.ra = rr->cr_ra;
+ rr->cr_hist[0].ref.t1 = ref->t1;
+ rr->cr_hist[0].ref.t2 = ref->t2;
+ rr->cr_hist[0].ref.t3_low = ref->t3_low;
+ rr->cr_hist[0].ref.t3_high = ref->t3_high;
+ }
+
+ if (!osmo_timer_pending(&rr->vgcs.t3130)) {
+ uint8_t uplink_ref;
+
+ /* Only try up to 3 times. */
+ if (!rr->vgcs.uplink_tries) {
+ LOGP(DRR, LOGL_NOTICE, "Abort uplink access, due uplink access timeout.\n");
+ return gsm48_rr_uplink_access_abort(ms, RR_REL_CAUSE_LINK_FAILURE);
+ }
+
+ LOGP(DRR, LOGL_INFO, "Trying to access uplink.\n");
+
+ rr->vgcs.uplink_tries--;
+
+ /* See Table 9.1.45.1 */
+ uplink_ref = layer23_random();
+ uplink_ref &= 0x1f;
+ uplink_ref |= 0xc0;
+
+ /* store value, mask and history */
+ rr->cr_ra = uplink_ref;
+ rr->cr_hist[4].valid = 0;
+ rr->cr_hist[3].valid = 0;
+ rr->cr_hist[2].valid = 0;
+ rr->cr_hist[1].valid = 0;
+ rr->cr_hist[0].valid = 0;
+
+ /* Reset counter. */
+ rr->vgcs.uplink_counter = 0;
+
+ /* Start T3130. */
+ start_rr_t3130(rr, GSM_T3130_MS);
+ }
+
+ /* Send random access bursts up to 5 times. */
+ if (rr->vgcs.uplink_counter < 5) {
+ int delay_ms;
+
+ /* The first UPLINK ACCESS message shall be delayed between 0..20ms.
+ * Subsequent UPLINK ACCESS messages shall be delayed 100ms + 0..20ms. */
+ delay_ms = (layer23_random() & 0xffff) / 3277;
+ if (rr->vgcs.uplink_counter)
+ delay_ms += 100;
+
+ gsm48_rr_tx_rand_acc_dedicated(ms, rr->cr_ra, delay_ms * 26 / 120, rr->vgcs.uic);
+ rr->vgcs.uplink_counter++;
+ }
+
+ return 0;
+}
+
+/* Whenever uplink access is released or failed for some reason. */
+static int gsm48_rr_uplink_access_abort(struct osmocom_ms *ms, uint8_t cause)
+{
+ struct gsm48_rrlayer *rr = &ms->rrlayer;
+ struct msgb *nmsg;
+ struct gsm48_rr_hdr *nrrh;
+
+ /* Stop group transmit mode timers. */
+ stop_rr_t3128(rr);
+ stop_rr_t3130(rr);
+
+ /* Turn off transmitter. */
+ rr->cd_now.tch_flags |= L1CTL_TCH_FLAG_RXONLY;
+ gsm48_rr_set_mode(ms, rr->cd_now.chan_nr, rr->cd_now.mode, rr->cd_now.tch_flags);
+
+ /* Only return IDLE without changing channel, because we are still in group transmit mode. */
+ new_rr_state(rr, GSM48_RR_ST_IDLE);
+
+ /* Set group state to receive mode. */
+ rr->vgcs.group_state = GSM48_RR_GST_RECEIVE;
+
+ nmsg = gsm48_rr_msgb_alloc(GSM48_RR_UPLINK_REL_IND);
+ if (!nmsg)
+ return -ENOMEM;
+ nrrh = (struct gsm48_rr_hdr *)nmsg->data;
+ nrrh->cause = cause;
+ return gsm48_rr_upmsg(ms, nmsg);
+}
+
+/* send talker indication */
+static int gsm48_rr_tx_talker_indication(struct osmocom_ms *ms)
+{
+ struct gsm48_rrlayer *rr = &ms->rrlayer;
+ struct msgb *nmsg;
+ struct gsm48_hdr *gh;
+ struct gsm48_talker_indication *ti;
+
+ LOGP(DRR, LOGL_INFO, "TALKER INDICATION\n");
+
+ nmsg = gsm48_l3_msgb_alloc();
+ if (!nmsg)
+ return -ENOMEM;
+ gh = (struct gsm48_hdr *) msgb_put(nmsg, sizeof(*gh));
+ ti = (struct gsm48_talker_indication *) msgb_put(nmsg, sizeof(*ti));
+
+ gh->proto_discr = GSM48_PDISC_RR;
+ gh->msg_type = GSM48_MT_RR_TALKER_IND;
+
+ /* classmark 2 */
+ ti->cm2_len = sizeof(ti->cm2);
+ gsm48_rr_enc_cm2(ms, &ti->cm2, rr->cd_now.arfcn);
+ /* mobile identity (Use TMSI if available.) */
+ gsm48_encode_mi_lv(ms, nmsg, GSM_MI_TYPE_TMSI, false);
+
+ /* start establishmnet */
+ return gsm48_send_rsl(ms, RSL_MT_EST_REQ, nmsg, 0);
+}
+
+/*
* random access
*/
@@ -1636,7 +2135,7 @@
&& (!cs->selected || (cs->state != GSM322_C3_CAMPED_NORMALLY
&& cs->state != GSM322_C7_CAMPED_ANY_CELL))) {
LOGP(DRR, LOGL_INFO, "Paging, but not camping, ignore.\n");
- return -EINVAL;
+ return -EINVAL;
}
/* ignore channel request while not camping on a cell */
@@ -3357,7 +3856,7 @@
gsm48_rr_tx_meas_rep(ms);
/* establish */
- LOGP(DRR, LOGL_INFO, "establishing channel in dedicated mode\n");
+ LOGP(DRR, LOGL_INFO, "establishing channel in dedicated/group mode\n");
if (rsl_dec_chan_nr(cd->chan_nr, &ch_type, &ch_subch, &ch_ts) != 0) {
LOGP(DRR, LOGL_ERROR,
@@ -3701,6 +4200,12 @@
struct msgb *nmsg;
struct gsm48_rr_hdr *nrrh;
+ /* Handle on group channel. */
+ if (rr->vgcs.group_state == GSM48_RR_GST_TRANSMIT) {
+ LOGP(DRR, LOGL_INFO, "Returning to group receive mode, due to link release indication.\n");
+ return gsm48_rr_uplink_access_abort(ms, RR_REL_CAUSE_NORMAL);
+ }
+
/* switch back to old channel, if modify/ho failed */
switch (rr->modify_state) {
case GSM48_RR_MOD_ASSIGN:
@@ -3770,6 +4275,9 @@
new_rr_state(rr, GSM48_RR_ST_REL_PEND);
+ /* When we receive a channel release, we are not just releasing the transmit mode. */
+ rr->vgcs.group_state = GSM48_RR_GST_OFF;
+
/* start T3110, so that two DISCs can be sent due to T200 timeout */
start_rr_t3110(rr, 1, 500000);
@@ -4831,6 +5339,16 @@
return 0;
}
+/* send HANDOVER/UPLINK ACCESS burst (9.1.14) */
+static int gsm48_rr_tx_rand_acc_dedicated(struct osmocom_ms *ms, uint8_t ref, uint16_t offset, int8_t uic)
+{
+ struct gsm48_rrlayer *rr = &ms->rrlayer;
+
+ LOGP(DRR, LOGL_INFO, "send access burst on DCCH (ref 0x%02x)\n", ref);
+
+ return l1ctl_tx_rach_req(ms, rr->cd_now.chan_nr, 0x00, ref, 0, offset, uic);
+}
+
/* send all queued messages down to layer 2 */
static int gsm48_rr_dequeue_down(struct osmocom_ms *ms)
{
@@ -4853,17 +5371,27 @@
return 0;
}
-/* channel is resumed in dedicated mode */
+/* Channel is resumed in dedicated mode or uplink is estabished. */
static int gsm48_rr_estab_cnf_dedicated(struct osmocom_ms *ms, struct msgb *msg)
{
struct gsm48_rrlayer *rr = &ms->rrlayer;
+ struct msgb *nmsg;
- LOGP(DRR, LOGL_INFO, "data link is resumed\n");
+ if (rr->vgcs.group_state == GSM48_RR_GST_TRANSMIT) {
+ LOGP(DRR, LOGL_INFO, "data link established on uplink\n");
- /* transmit queued frames during ho / ass transition */
- gsm48_rr_dequeue_down(ms);
+ /* Confirm uplink access. */
+ nmsg = gsm48_rr_msgb_alloc(GSM48_RR_UPLINK_CNF);
+ if (nmsg)
+ gsm48_rr_upmsg(ms, nmsg);
+ } else {
+ LOGP(DRR, LOGL_INFO, "data link is resumed\n");
- rr->modify_state = GSM48_RR_MOD_NONE;
+ /* transmit queued frames during ho / ass transition */
+ gsm48_rr_dequeue_down(ms);
+
+ rr->modify_state = GSM48_RR_MOD_NONE;
+ }
return 0;
}
@@ -5159,6 +5687,9 @@
goto reject;
}
+ /* Initial uplink state. */
+ rr->vgcs.uplink_free = false;
+
/* Set group state to receive mode. */
rr->vgcs.group_state = GSM48_RR_GST_RECEIVE;
@@ -5191,6 +5722,38 @@
struct gsm48_rrlayer *rr = &ms->rrlayer;
struct msgb *nmsg;
struct gsm48_rr_hdr *nrrh;
+ uint8_t *mode;
+
+ /* Stop group receive and transmit timers. */
+ stop_rr_t_ul_free(rr);
+ stop_rr_t3128(rr);
+ stop_rr_t3130(rr);
+
+ if (rr->state == GSM48_RR_ST_DEDICATED || rr->state == GSM48_RR_ST_REL_PEND) {
+ struct msgb *nmsg;
+
+ LOGP(DRR, LOGL_INFO, "Channel lost, send (local) release to layer 2.\n");
+
+ /* Go into group receive mode, so that the channel gets released on LAPD release confirm. */
+ rr->vgcs.group_state = GSM48_RR_GST_RECEIVE;
+ if (rr->state != GSM48_RR_ST_REL_PEND)
+ new_rr_state(rr, GSM48_RR_ST_REL_PEND);
+
+ /* release message */
+ nmsg = gsm48_l3_msgb_alloc();
+ if (!nmsg)
+ return -ENOMEM;
+ mode = msgb_put(nmsg, 2);
+ mode[0] = RSL_IE_RELEASE_MODE;
+ mode[1] = RSL_REL_LOCAL_END;
+ gsm48_send_rsl_nol3(ms, RSL_MT_REL_REQ, nmsg, 0);
+
+ /* release SAPI 3 link, if exits */
+ gsm48_release_sapi3_link(ms);
+
+ /* Wait for LAPD to confirm. Then return idle. */
+ return 0;
+ }
/* Go back to IDLE mode. */
rr->vgcs.group_state = GSM48_RR_GST_OFF;
@@ -5214,6 +5777,21 @@
if (rr->vgcs.group_state == GSM48_RR_GST_OFF)
return 0;
+ if (rr->state == GSM48_RR_ST_CONN_PEND || rr->state == GSM48_RR_ST_DEDICATED) {
+ LOGP(DRR, LOGL_INFO, "Connot release group channel yet, perform uplink release first.\n");
+ gsm48_rr_uplink_rel_req(ms, msg);
+ if (rr->state == GSM48_RR_ST_REL_PEND) {
+ /* Leave the group call state, so that we change to IDLE when we released the uplink. */
+ rr->vgcs.group_state = GSM48_RR_GST_OFF;
+ return 0;
+ }
+ }
+
+ /* Stop group receive and transmit timers. */
+ stop_rr_t_ul_free(rr);
+ stop_rr_t3128(rr);
+ stop_rr_t3130(rr);
+
/* Unset group state. Wait, if release is pending. */
rr->vgcs.group_state = GSM48_RR_GST_OFF;
if (rr->state != GSM48_RR_ST_IDLE) {
@@ -5226,6 +5804,89 @@
return 0;
}
+/* Request uplink in group receive mode. */
+static int gsm48_rr_uplink_req(struct osmocom_ms *ms, struct msgb *msg)
+{
+ struct gsm48_rrlayer *rr = &ms->rrlayer;
+ struct msgb *nmsg;
+ struct gsm48_rr_hdr *nrrh;
+
+ /* Only in group receive mode */
+ if (rr->state != GSM48_RR_ST_IDLE || rr->vgcs.group_state != GSM48_RR_GST_RECEIVE) {
+ LOGP(DRR, LOGL_INFO, "We are not in group receive mode yet, rejecting!\n");
+ nmsg = gsm48_rr_msgb_alloc(GSM48_RR_UPLINK_REL_IND);
+ if (!nmsg)
+ return -ENOMEM;
+ nrrh = (struct gsm48_rr_hdr *)nmsg->data;
+ nrrh->cause = RR_REL_CAUSE_TRY_LATER;
+ return gsm48_rr_upmsg(ms, nmsg);
+ }
+
+ LOGP(DRR, LOGL_INFO, "Changing from group receive mode to group transmit mode.\n");
+
+ /* Enter uplink access procedure. */
+ new_rr_state(rr, GSM48_RR_ST_CONN_PEND);
+
+ /* Set group state to transmit mode. */
+ rr->vgcs.group_state = GSM48_RR_GST_TRANSMIT;
+
+ /* Uplink investigation procedure (3.3.1.2.1.1) */
+ if (!rr->vgcs.uplink_free) {
+ start_rr_t3128(rr, GSM_T3128_MS);
+ return 0;
+ }
+
+ rr->vgcs.uplink_tries = 3;
+ return gsm48_rr_uplink_access(ms, NULL);
+}
+
+/* Leave uplink, also called when leaving group channel. */
+static int gsm48_rr_uplink_rel_req(struct osmocom_ms *ms, struct msgb *msg)
+{
+ struct gsm48_rrlayer *rr = &ms->rrlayer;
+ struct gsm_settings *set = &ms->settings;
+ struct msgb *nmsg;
+ uint8_t *mode;
+
+ /* Only in group transmit mode */
+ if (rr->vgcs.group_state != GSM48_RR_GST_TRANSMIT)
+ return -EINVAL;
+
+ /* Stop group transmit mode timers. */
+ stop_rr_t3128(rr);
+ stop_rr_t3130(rr);
+
+ /* Continue if in dedicated mode, so we release and wait for uplink to become free. */
+ if (rr->state != GSM48_RR_ST_DEDICATED)
+ return 0;
+
+ LOGP(DRR, LOGL_INFO, "Returning from group transmit to group receive mode.\n");
+
+ /* Leave uplink, wait for uplink being free, channel release or channel/link failure. */
+ gsm48_rr_tx_uplink_release(ms, GSM48_RR_CAUSE_LEAVE_GROUP_CA);
+
+ /* Go into release pending mode. */
+ new_rr_state(rr, GSM48_RR_ST_REL_PEND);
+
+ /* Special setting where we release locally. This means we wait for free uplink an then release. */
+ if (set->uplink_release_local) {
+ LOGP(DRR, LOGL_INFO, "Release L2 locally as specified via VTY. Wait for UPLINK FREE.\n");
+ return 0;
+ }
+
+ /* Release dedicated mode. */
+ /* disconnect the main signalling link */
+ nmsg = gsm48_l3_msgb_alloc();
+ if (!nmsg)
+ return -ENOMEM;
+ mode = msgb_put(nmsg, 2);
+ mode[0] = RSL_IE_RELEASE_MODE;
+ mode[1] = RSL_REL_NORMAL;
+ gsm48_send_rsl_nol3(ms, RSL_MT_REL_REQ, nmsg, 0);
+
+ return 0;
+}
+
/* 3.4.2 transfer data in dedicated mode */
static int gsm48_rr_data_req(struct osmocom_ms *ms, struct msgb *msg)
{
@@ -5311,6 +5972,9 @@
case GSM48_MT_RR_CHAN_REL:
rc = gsm48_rr_rx_chan_rel(ms, msg);
break;
+ case GSM48_MT_RR_UPLINK_RELEASE:
+ rc = gsm48_rr_rx_uplink_release(ms, msg);
+ break;
case GSM48_MT_RR_APP_INFO:
LOGP(DRR, LOGL_NOTICE, "APP INFO not supported!\n");
break;
@@ -5427,6 +6091,8 @@
return -EINVAL;
}
switch (sgh->msg_type) {
+ case GSM48_MT_RR_SH_UL_FREE:
+ return gsm48_rr_rx_uplink_free(ms, msg);
case GSM48_MT_RR_SH_FACCH:
return gsm48_rr_rx_notif_facch(ms, msg);
case GSM48_MT_RR_SH_SI10:
@@ -5462,6 +6128,10 @@
}
gh = msgb_l3(msg);
switch (gh->msg_type) {
+ case GSM48_MT_RR_VGCS_UPL_GRANT:
+ return gsm48_rr_rx_vgcs_uplink_grant(ms, msg);
+ case GSM48_MT_RR_UPLINK_BUSY:
+ return gsm48_rr_rx_uplink_busy(ms, msg);
case GSM48_MT_RR_CHAN_REL:
return gsm48_rr_rx_chan_rel_ui(ms, msg);
default:
@@ -5619,6 +6289,12 @@
uint16_t ma[64];
uint8_t ma_len;
+ /* Handle on group channel. */
+ if (rr->vgcs.group_state == GSM48_RR_GST_TRANSMIT) {
+ LOGP(DRR, LOGL_INFO, "Returning to group receive mode, due to link release confirm.\n");
+ return gsm48_rr_uplink_access_abort(ms, RR_REL_CAUSE_NORMAL);
+ }
+
/* switch back to old channel, if modify/ho failed */
switch (rr->modify_state) {
case GSM48_RR_MOD_ASSIGN:
@@ -5717,6 +6393,12 @@
if (rr->modify_state)
return 0;
+ /* Handle on group channel. */
+ if ((link_id & 7) == 0 && rr->vgcs.group_state == GSM48_RR_GST_TRANSMIT) {
+ LOGP(DRR, LOGL_INFO, "Returning to group receive mode, due to link failure.\n");
+ return gsm48_rr_uplink_access_abort(ms, RR_REL_CAUSE_LINK_FAILURE);
+ }
+
/* send abort ind to upper layer */
nmsg = gsm48_rr_msgb_alloc(GSM48_RR_ABORT_IND);
if (!nmsg)
@@ -5979,11 +6661,6 @@
{SBIT(GSM48_RR_ST_DEDICATED),
RSL_MT_SUSP_CONF, gsm48_rr_susp_cnf_dedicated},
-#if 0
- {SBIT(GSM48_RR_ST_DEDICATED),
- RSL_MT_CHAN_CNF, gsm48_rr_rand_acc_cnf_dedicated},
-#endif
-
{SBIT(GSM48_RR_ST_DEDICATED),
RSL_MT_ERROR_IND, gsm48_rr_mdl_error_ind},
};
@@ -6080,11 +6757,24 @@
"%s\n", ms->name, rsl_msg_name(msg_type),
gsm48_rr_state_names[rr->state]);
- if (rr->state == GSM48_RR_ST_CONN_PEND
- && msg_type == RSL_MT_CHAN_CONF) {
- rc = gsm48_rr_tx_rand_acc(ms, msg);
- msgb_free(msg);
- return rc;
+ if (msg_type == RSL_MT_CHAN_CONF) {
+ /* Recevie confirm to get the FN when the access burst was transmitted on VGCS channel. */
+ if (rr->state == GSM48_RR_ST_CONN_PEND && rr->vgcs.group_state == GSM48_RR_GST_TRANSMIT) {
+ rc = gsm48_rr_uplink_access(ms, msg);
+ msgb_free(msg);
+ return rc;
+ }
+ /* Ignore subsequent access bursts in dedicated group transmit mode. */
+ if (rr->state == GSM48_RR_ST_DEDICATED && rr->vgcs.group_state == GSM48_RR_GST_TRANSMIT) {
+ msgb_free(msg);
+ return 0;
+ }
+ /* Recevie confirm to get the FN when the access burst was transmitted on CCCH. */
+ if (rr->state == GSM48_RR_ST_CONN_PEND) {
+ rc = gsm48_rr_tx_rand_acc(ms, msg);
+ msgb_free(msg);
+ return rc;
+ }
}
LOGP(DRSL, LOGL_NOTICE, "RSLms message unhandled\n");
@@ -6144,6 +6834,12 @@
{ALL_STATES,
GSM48_RR_GROUP_REL_REQ, gsm48_rr_group_rel_req},
+ /* NOTE: If not IDLE, it is rejected there. */
+ {ALL_STATES, /* 3.3.1.2 */
+ GSM48_RR_UPLINK_REQ, gsm48_rr_uplink_req},
+
+ {ALL_STATES, /* 3.4.13.4 */
+ GSM48_RR_UPLINK_REL_REQ, gsm48_rr_uplink_rel_req},
};
#define RRDOWNSLLEN \
@@ -6285,6 +6981,9 @@
stop_rr_t3122(rr);
stop_rr_t3124(rr);
stop_rr_t3126(rr);
+ stop_rr_t_ul_free(rr);
+ stop_rr_t3128(rr);
+ stop_rr_t3130(rr);
/* Free pending list entries. */
asci_notif_list_free(rr);
@@ -6331,54 +7030,6 @@
osmo_timer_schedule(&rr->t3124, sec, micro);
}
-/* send HANDOVER ACCESS burst (9.1.14) */
-static int gsm48_rr_tx_hando_access(struct osmocom_ms *ms)
-{
- nmsg = msgb_alloc_headroom(20, 16, "HAND_ACCESS");
- if (!nmsg)
- return -ENOMEM;
- *msgb_put(nmsg, 1) = rr->hando_ref;
- todo burst
- return gsm48_send_rsl(ms, RSL_MT_RAND_ACC_REQ, nmsg, 0);
-}
-
-/* send next channel request in dedicated state */
-static int gsm48_rr_rand_acc_cnf_dedicated(struct osmocom_ms *ms, struct msgb *msg)
-{
- struct gsm48_rrlayer *rr = &ms->rrlayer;
- struct msgb *nmsg;
- int s;
-
- if (rr->modify_state != GSM48_RR_MOD_HANDO) {
- LOGP(DRR, LOGL_NOTICE, "Random access confirm, but not in handover state.\n");
- return 0;
- }
-
- /* send up to four handover access bursts */
- if (rr->hando_acc_left) {
- rr->hando_acc_left--;
- gsm48_rr_tx_hando_access(ms);
- return;
- }
-
- /* start timer for sending next HANDOVER ACCESS bursts afterwards */
- if (!osmo_timer_pending(&rr->t3124)) {
- if (allocated channel is SDCCH)
- start_rr_t3124(rr, GSM_T3124_675);
- else
- start_rr_t3124(rr, GSM_T3124_320);
- }
- if (!rr->n_chan_req) {
- start_rr_t3126(rr, 5, 0); /* TODO improve! */
- return 0;
- }
- rr->n_chan_req--;
-
- /* wait for PHYSICAL INFORMATION message or T3124 timeout */
- return 0;
-
-}
-
#endif
int gsm48_rr_tx_voice(struct osmocom_ms *ms, struct msgb *msg)
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