mm_state_{gb,iu}_fsm: Improve naming for detach event

The E_(P)MM_IMPLICIT_DETACH event was actually sent and handled when the
UE was considered to be detached, no matter the reason, be it due to
implicit detach, or Detach Request received, etc.
So, let's properly name the event to avoid confusions in the code.

Related: SYS#5389
Change-Id: I224ea9db80b4d96696934cea06349dab036f919b

6 files changed, 18 insertions, 20 deletions

diff --git a/include/osmocom/sgsn/gprs_mm_state_gb_fsm.h b/include/osmocom/sgsn/gprs_mm_state_gb_fsm.h
index 02dcac740..4237c2f94 100644
--- a/include/osmocom/sgsn/gprs_mm_state_gb_fsm.h
+++ b/include/osmocom/sgsn/gprs_mm_state_gb_fsm.h
@@ -14,9 +14,8 @@ enum mm_state_gb_fsm_states {
 
 enum mm_state_gb_fsm_events {
 	E_MM_GPRS_ATTACH,
-	/* E_GPRS_DETACH, TODO: not used */
+	E_MM_GPRS_DETACH,  /* MS becomes detached: due to Detach Req, RAU reject, implicit detach, etc. */
 	E_MM_PDU_RECEPTION,
-	E_MM_IMPLICIT_DETACH, /* = E_MM_CANCEL_LOCATION */
 	E_MM_READY_TIMER_EXPIRY,
 	/* E_FORCE_TO_STANDBY, TODO: not used */
 	/* E_ABNSORMAL_RLC_CONDITION, TODO: not used */
diff --git a/include/osmocom/sgsn/gprs_mm_state_iu_fsm.h b/include/osmocom/sgsn/gprs_mm_state_iu_fsm.h
index 7e11ac97c..6dae759b0 100644
--- a/include/osmocom/sgsn/gprs_mm_state_iu_fsm.h
+++ b/include/osmocom/sgsn/gprs_mm_state_iu_fsm.h
@@ -13,10 +13,9 @@ enum mm_state_iu_fsm_states {
 
 enum mm_state_iu_fsm_events {
 	E_PMM_PS_ATTACH,
-	/* E_PS_DETACH, TODO: not used */
+	E_PMM_PS_DETACH, /* UE becomes detached: due to Detach Req, RAU reject, implicit detach, etc. */
 	E_PMM_PS_CONN_RELEASE,
 	E_PMM_PS_CONN_ESTABLISH,
-	E_PMM_IMPLICIT_DETACH, /* = E_PS_ATTACH_REJECT, E_RAU_REJECT */
 	E_PMM_RA_UPDATE, /* = Serving RNC relocation */
 };
 
diff --git a/src/sgsn/gprs_gmm.c b/src/sgsn/gprs_gmm.c
index f05167f35..edddd2d8f 100644
--- a/src/sgsn/gprs_gmm.c
+++ b/src/sgsn/gprs_gmm.c
@@ -197,10 +197,10 @@ static void mm_ctx_cleanup_free(struct sgsn_mm_ctx *ctx, const char *log_text)
 
 	switch(ctx->ran_type) {
 	case MM_CTX_T_UTRAN_Iu:
-		osmo_fsm_inst_dispatch(ctx->iu.mm_state_fsm, E_PMM_IMPLICIT_DETACH, NULL);
+		osmo_fsm_inst_dispatch(ctx->iu.mm_state_fsm, E_PMM_PS_DETACH, NULL);
 		break;
 	case MM_CTX_T_GERAN_Gb:
-		osmo_fsm_inst_dispatch(ctx->gb.mm_state_fsm, E_MM_IMPLICIT_DETACH, NULL);
+		osmo_fsm_inst_dispatch(ctx->gb.mm_state_fsm, E_MM_GPRS_DETACH, NULL);
 		break;
 	}
 
diff --git a/src/sgsn/gprs_gmm_fsm.c b/src/sgsn/gprs_gmm_fsm.c
index caec5864c..78946b5b1 100644
--- a/src/sgsn/gprs_gmm_fsm.c
+++ b/src/sgsn/gprs_gmm_fsm.c
@@ -199,9 +199,9 @@ void gmm_fsm_allstate_action(struct osmo_fsm_inst *fi, uint32_t event, void *dat
 			gmm_fsm_state_chg(fi, ST_GMM_DEREGISTERED);
 		default:
 			if (mmctx->ran_type == MM_CTX_T_GERAN_Gb)
-				osmo_fsm_inst_dispatch(mmctx->gb.mm_state_fsm, E_MM_IMPLICIT_DETACH, NULL);
+				osmo_fsm_inst_dispatch(mmctx->gb.mm_state_fsm, E_MM_GPRS_DETACH, NULL);
 			else if (mmctx->ran_type == MM_CTX_T_UTRAN_Iu) {
-				osmo_fsm_inst_dispatch(mmctx->iu.mm_state_fsm, E_PMM_IMPLICIT_DETACH, NULL);
+				osmo_fsm_inst_dispatch(mmctx->iu.mm_state_fsm, E_PMM_PS_DETACH, NULL);
 				mmctx->gb.llme = rat_chg->llme;
 			}
 
diff --git a/src/sgsn/gprs_mm_state_gb_fsm.c b/src/sgsn/gprs_mm_state_gb_fsm.c
index f8653f6b0..6e812d31d 100644
--- a/src/sgsn/gprs_mm_state_gb_fsm.c
+++ b/src/sgsn/gprs_mm_state_gb_fsm.c
@@ -71,7 +71,7 @@ static void st_mm_ready(struct osmo_fsm_inst *fi, uint32_t event, void *data)
 	case E_MM_READY_TIMER_EXPIRY:
 		mm_state_gb_fsm_state_chg(fi, ST_MM_STANDBY);
 		break;
-	case E_MM_IMPLICIT_DETACH:
+	case E_MM_GPRS_DETACH:
 		mm_state_gb_fsm_state_chg(fi, ST_MM_IDLE);
 		break;
 	case E_MM_PDU_RECEPTION:
@@ -90,7 +90,7 @@ static void st_mm_standby(struct osmo_fsm_inst *fi, uint32_t event, void *data)
 	case E_MM_PDU_RECEPTION:
 		mm_state_gb_fsm_state_chg(fi, ST_MM_READY);
 		break;
-	case E_MM_IMPLICIT_DETACH:
+	case E_MM_GPRS_DETACH:
 		mm_state_gb_fsm_state_chg(fi, ST_MM_IDLE);
 		break;
 	}
@@ -105,13 +105,13 @@ static struct osmo_fsm_state mm_state_gb_fsm_states[] = {
 		.action = st_mm_idle,
 	},
 	[ST_MM_READY] = {
-		.in_event_mask = X(E_MM_READY_TIMER_EXPIRY) | X(E_MM_RA_UPDATE) | X(E_MM_IMPLICIT_DETACH) | X(E_MM_PDU_RECEPTION),
+		.in_event_mask = X(E_MM_READY_TIMER_EXPIRY) | X(E_MM_RA_UPDATE) | X(E_MM_GPRS_DETACH) | X(E_MM_PDU_RECEPTION),
 		.out_state_mask = X(ST_MM_IDLE) | X(ST_MM_STANDBY),
 		.name = "Ready",
 		.action = st_mm_ready,
 	},
 	[ST_MM_STANDBY] = {
-		.in_event_mask = X(E_MM_PDU_RECEPTION) | X(E_MM_IMPLICIT_DETACH),
+		.in_event_mask = X(E_MM_PDU_RECEPTION) | X(E_MM_GPRS_DETACH),
 		.out_state_mask = X(ST_MM_IDLE) | X(ST_MM_READY),
 		.name = "Standby",
 		.action = st_mm_standby,
@@ -121,7 +121,7 @@ static struct osmo_fsm_state mm_state_gb_fsm_states[] = {
 const struct value_string mm_state_gb_fsm_event_names[] = {
 	OSMO_VALUE_STRING(E_MM_GPRS_ATTACH),
 	OSMO_VALUE_STRING(E_MM_PDU_RECEPTION),
-	OSMO_VALUE_STRING(E_MM_IMPLICIT_DETACH),
+	OSMO_VALUE_STRING(E_MM_GPRS_DETACH),
 	OSMO_VALUE_STRING(E_MM_READY_TIMER_EXPIRY),
 	OSMO_VALUE_STRING(E_MM_RA_UPDATE),
 	{ 0, NULL }
diff --git a/src/sgsn/gprs_mm_state_iu_fsm.c b/src/sgsn/gprs_mm_state_iu_fsm.c
index 3f1336b2a..b1604f83b 100644
--- a/src/sgsn/gprs_mm_state_iu_fsm.c
+++ b/src/sgsn/gprs_mm_state_iu_fsm.c
@@ -61,7 +61,7 @@ static void st_pmm_detached(struct osmo_fsm_inst *fi, uint32_t event, void *data
 	case E_PMM_PS_ATTACH:
 		mm_state_iu_fsm_state_chg(fi, ST_PMM_CONNECTED);
 		break;
-	case E_PMM_IMPLICIT_DETACH:
+	case E_PMM_PS_DETACH:
 		break;
 	}
 }
@@ -75,7 +75,7 @@ static void st_pmm_connected(struct osmo_fsm_inst *fi, uint32_t event, void *dat
 		sgsn_ranap_iu_free(ctx);
 		mm_state_iu_fsm_state_chg(fi, ST_PMM_IDLE);
 		break;
-	case E_PMM_IMPLICIT_DETACH:
+	case E_PMM_PS_DETACH:
 		sgsn_ranap_iu_release_free(ctx, NULL);
 		mm_state_iu_fsm_state_chg(fi, ST_PMM_DETACHED);
 		break;
@@ -98,7 +98,7 @@ static void st_pmm_idle(struct osmo_fsm_inst *fi, uint32_t event, void *data)
 	case E_PMM_PS_CONN_ESTABLISH:
 		mm_state_iu_fsm_state_chg(fi, ST_PMM_CONNECTED);
 		break;
-	case E_PMM_IMPLICIT_DETACH:
+	case E_PMM_PS_DETACH:
 		mm_state_iu_fsm_state_chg(fi, ST_PMM_DETACHED);
 		break;
 	}
@@ -106,7 +106,7 @@ static void st_pmm_idle(struct osmo_fsm_inst *fi, uint32_t event, void *data)
 
 static struct osmo_fsm_state mm_state_iu_fsm_states[] = {
 	[ST_PMM_DETACHED] = {
-		.in_event_mask = X(E_PMM_PS_ATTACH) | X(E_PMM_IMPLICIT_DETACH),
+		.in_event_mask = X(E_PMM_PS_ATTACH) | X(E_PMM_PS_DETACH),
 		.out_state_mask = X(ST_PMM_CONNECTED),
 		.name = "Detached",
 		.action = st_pmm_detached,
@@ -115,14 +115,14 @@ static struct osmo_fsm_state mm_state_iu_fsm_states[] = {
 		.in_event_mask =
 			X(E_PMM_PS_CONN_RELEASE) |
 			X(E_PMM_RA_UPDATE) |
-			X(E_PMM_IMPLICIT_DETACH),
+			X(E_PMM_PS_DETACH),
 		.out_state_mask = X(ST_PMM_DETACHED) | X(ST_PMM_IDLE),
 		.name = "Connected",
 		.action = st_pmm_connected,
 	},
 	[ST_PMM_IDLE] = {
 		.in_event_mask =
-			X(E_PMM_IMPLICIT_DETACH) |
+			X(E_PMM_PS_DETACH) |
 			X(E_PMM_PS_CONN_ESTABLISH) |
 			X(E_PMM_PS_ATTACH),
 		.out_state_mask = X(ST_PMM_DETACHED) | X(ST_PMM_CONNECTED),
@@ -136,7 +136,7 @@ const struct value_string mm_state_iu_fsm_event_names[] = {
 	OSMO_VALUE_STRING(E_PMM_PS_ATTACH),
 	OSMO_VALUE_STRING(E_PMM_PS_CONN_RELEASE),
 	OSMO_VALUE_STRING(E_PMM_PS_CONN_ESTABLISH),
-	OSMO_VALUE_STRING(E_PMM_IMPLICIT_DETACH),
+	OSMO_VALUE_STRING(E_PMM_PS_DETACH),
 	OSMO_VALUE_STRING(E_PMM_RA_UPDATE),
 	{ 0, NULL }
 };