diff --git a/channels/chan_dahdi.c b/channels/chan_dahdi.c
index 884e97e364..c7f9244741 100644
--- a/channels/chan_dahdi.c
+++ b/channels/chan_dahdi.c
@@ -775,6 +775,10 @@ static struct ast_jb_conf global_jbconf;
 /*! \brief Signaling types that need to use MF detection should be placed in this macro */
 #define NEED_MFDETECT(p) (((p)->sig == SIG_FEATDMF) || ((p)->sig == SIG_FEATDMF_TA) || ((p)->sig == SIG_E911) || ((p)->sig == SIG_FGC_CAMA) || ((p)->sig == SIG_FGC_CAMAMF) || ((p)->sig == SIG_FEATB))
 
+/*! \brief Whether a channel is FXO signaled */
+#define IS_FXO_SIG(p) (((p)->sig == SIG_FXOKS) || ((p)->sig == SIG_FXOLS) || ((p)->sig == SIG_FXOGS))
+#define CHAN_IS_FXO_SIG(sig) (sig == SIG_FXOKS || sig == SIG_FXOLS || sig == SIG_FXOGS)
+
 static const char tdesc[] = "DAHDI Telephony"
 #if defined(HAVE_PRI) || defined(HAVE_SS7) || defined(HAVE_OPENR2)
 	" w/"
@@ -8050,8 +8054,7 @@ static struct ast_frame *dahdi_handle_event(struct ast_channel *ast)
 				break;
 			}
 			/* Otherwise, immediate recall */
-			if ((p->sig == SIG_FXOLS) || (p->sig == SIG_FXOKS) || (p->sig == SIG_FXOGS))
-			{
+			if (IS_FXO_SIG(p)) {
 				/* Make sure it starts ringing */
 				dahdi_set_hook(p->subs[SUB_REAL].dfd, DAHDI_RINGOFF);
 				dahdi_set_hook(p->subs[SUB_REAL].dfd, DAHDI_RING);
@@ -8164,8 +8167,7 @@ static struct ast_frame *dahdi_handle_event(struct ast_channel *ast)
 		if (p->inalarm) break;
 		if (p->oprmode < 0)
 		{
-			if ((p->sig == SIG_FXOLS) || (p->sig == SIG_FXOKS) || (p->sig == SIG_FXOGS))
-			{
+			if (IS_FXO_SIG(p)) {
 				/* Make sure it stops ringing */
 				dahdi_set_hook(p->subs[SUB_REAL].dfd, DAHDI_RINGOFF);
 				tone_zone_play_tone(p->oprpeer->subs[SUB_REAL].dfd, -1);
@@ -9359,7 +9361,7 @@ static int dahdi_write(struct ast_channel *ast, struct ast_frame *frame)
 		return -1;
 	}
 
-	if (p->sig == SIG_FXOLS || p->sig == SIG_FXOKS || p->sig == SIG_FXOGS) {
+	if (IS_FXO_SIG(p)) {
 		struct analog_pvt *analog_p = p->sig_pvt;
 		if (analog_p->callwaitingdeluxepending) {
 			unsigned int mssinceflash = ast_tvdiff_ms(ast_tvnow(), analog_p->flashtime);
@@ -9759,7 +9761,7 @@ static struct ast_channel *dahdi_new(struct dahdi_pvt *i, int state, int startpb
 	if (state == AST_STATE_RING)
 		ast_channel_rings_set(tmp, 1);
 	ast_channel_tech_pvt_set(tmp, i);
-	if ((i->sig == SIG_FXOKS) || (i->sig == SIG_FXOGS) || (i->sig == SIG_FXOLS)) {
+	if (IS_FXO_SIG(i)) {
 		/* Only FXO signalled stuff can be picked up */
 		ast_channel_callgroup_set(tmp, i->callgroup);
 		ast_channel_pickupgroup_set(tmp, i->pickupgroup);
@@ -13125,7 +13127,7 @@ static struct dahdi_pvt *mkintf(int channel, const struct dahdi_chan_conf *conf,
 		}
 		tmp->ringt_base = ringt_base;
 		tmp->firstradio = 0;
-		if ((chan_sig == SIG_FXOKS) || (chan_sig == SIG_FXOLS) || (chan_sig == SIG_FXOGS))
+		if (CHAN_IS_FXO_SIG(chan_sig))
 			tmp->permcallwaiting = conf->chan.callwaiting;
 		else
 			tmp->permcallwaiting = 0;
@@ -18992,7 +18994,7 @@ static int process_dahdi(struct dahdi_chan_conf *confp, const char *cat, struct
 		} else if (!strcasecmp(v->name, "group")) {
 			confp->chan.group = ast_get_group(v->value);
 		} else if (!strcasecmp(v->name, "callgroup")) {
-			if (!((confp->chan.sig == SIG_FXOKS) || (confp->chan.sig == SIG_FXOGS) || (confp->chan.sig == SIG_FXOLS))) {
+			if (!CHAN_IS_FXO_SIG(confp->chan.sig)) {
 				ast_log(LOG_WARNING, "Only FXO signalled channels may belong to a call group\n");
 			}
 			if (!strcasecmp(v->value, "none"))
@@ -19000,7 +19002,7 @@ static int process_dahdi(struct dahdi_chan_conf *confp, const char *cat, struct
 			else
 				confp->chan.callgroup = ast_get_group(v->value);
 		} else if (!strcasecmp(v->name, "pickupgroup")) {
-			if (!((confp->chan.sig == SIG_FXOKS) || (confp->chan.sig == SIG_FXOGS) || (confp->chan.sig == SIG_FXOLS))) {
+			if (!CHAN_IS_FXO_SIG(confp->chan.sig)) {
 				ast_log(LOG_WARNING, "Only FXO signalled channels may belong to a pickup group\n");
 			}
 			if (!strcasecmp(v->value, "none"))
@@ -19008,12 +19010,12 @@ static int process_dahdi(struct dahdi_chan_conf *confp, const char *cat, struct
 			else
 				confp->chan.pickupgroup = ast_get_group(v->value);
 		} else if (!strcasecmp(v->name, "namedcallgroup")) {
-			if (!((confp->chan.sig == SIG_FXOKS) || (confp->chan.sig == SIG_FXOGS) || (confp->chan.sig == SIG_FXOLS))) {
+			if (!CHAN_IS_FXO_SIG(confp->chan.sig)) {
 				ast_log(LOG_WARNING, "Only FXO signalled channels may belong to a named call group\n");
 			}
 			confp->chan.named_callgroups = ast_get_namedgroups(v->value);
 		} else if (!strcasecmp(v->name, "namedpickupgroup")) {
-			if (!((confp->chan.sig == SIG_FXOKS) || (confp->chan.sig == SIG_FXOGS) || (confp->chan.sig == SIG_FXOLS))) {
+			if (!CHAN_IS_FXO_SIG(confp->chan.sig)) {
 				ast_log(LOG_WARNING, "Only FXO signalled channels may belong to a named pickup group\n");
 			}
 			confp->chan.named_pickupgroups = ast_get_namedgroups(v->value);
diff --git a/channels/sig_analog.c b/channels/sig_analog.c
index d45644fa1d..cbedfb2905 100644
--- a/channels/sig_analog.c
+++ b/channels/sig_analog.c
@@ -104,9 +104,13 @@ static const struct {
 	 * way to do this in the dialplan now. */
 };
 
+/*! \brief Whether a channel is FXS signaled */
 #define ISTRUNK(p) ((p->sig == ANALOG_SIG_FXSLS) || (p->sig == ANALOG_SIG_FXSKS) || \
 					(p->sig == ANALOG_SIG_FXSGS))
 
+/*! \brief Whether a channel is FXO signaled */
+#define IS_FXO_SIG(p) (((p)->sig == ANALOG_SIG_FXOKS) || ((p)->sig == ANALOG_SIG_FXOLS) || ((p)->sig == ANALOG_SIG_FXOGS))
+
 enum analog_sigtype analog_str_to_sigtype(const char *name)
 {
 	int i;
@@ -838,7 +842,7 @@ int analog_available(struct analog_pvt *p)
 	}
 
 	/* If it's not an FXO, forget about call wait */
-	if ((p->sig != ANALOG_SIG_FXOKS) && (p->sig != ANALOG_SIG_FXOLS) && (p->sig != ANALOG_SIG_FXOGS)) {
+	if (!IS_FXO_SIG(p)) {
 		return 0;
 	}
 
@@ -3228,7 +3232,7 @@ static struct ast_frame *__analog_handle_event(struct analog_pvt *p, struct ast_
 		analog_get_and_handle_alarms(p);
 		cause_code->ast_cause = AST_CAUSE_NETWORK_OUT_OF_ORDER;
 	case ANALOG_EVENT_ONHOOK:
-		if (p->calledsubscriberheld && (p->sig == ANALOG_SIG_FXOLS || p->sig == ANALOG_SIG_FXOGS || p->sig == ANALOG_SIG_FXOKS) && idx == ANALOG_SUB_REAL) {
+		if (p->calledsubscriberheld && IS_FXO_SIG(p) && idx == ANALOG_SUB_REAL) {
 			ast_debug(4, "Channel state on %s is %d\n", ast_channel_name(ast), ast_channel_state(ast));
 			/* Called Subscriber Held: don't let the called party hang up on an incoming call immediately (if it's the only call). */
 			if (p->subs[ANALOG_SUB_CALLWAIT].owner || p->subs[ANALOG_SUB_THREEWAY].owner) {
@@ -4421,7 +4425,7 @@ void analog_delete(struct analog_pvt *doomed)
 int analog_config_complete(struct analog_pvt *p)
 {
 	/* No call waiting on non FXS channels */
-	if ((p->sig != ANALOG_SIG_FXOKS) && (p->sig != ANALOG_SIG_FXOLS) && (p->sig != ANALOG_SIG_FXOGS)) {
+	if (!IS_FXO_SIG(p)) {
 		p->permcallwaiting = 0;
 	}