Revert "quectel: EC21 needs aux channel to be the first mux channel"

This reverts commit 1868dbf2b3.
Development for this was done on EC21 firmware version
EC21EFAR06A01M4G_BETA0318. It now turns out, that actual release
firmware versions for this modem again need the original mux order with
aux channel as the second mux channel. (We know for sure for firmware
version EC21EFAR06A03M4G.)
We do not know for sure when and for what firmware versions quectel did
the switch back on the mux order, but we suspect that the "BETA"
firmware is the only one with the reversed mux order. This "BETA"
firmware was only given out for development purposes and will not appear
"in the wild", so we revert the patch here and hope for the best.

plugins/quectel.c

@@ -78,27 +78,6 @@ static const uint8_t gsm0710_terminate[] = {
 	0xf9, /* close flag */
 };
 
-enum mux_type {
-	QUECTEL_MUX_TYPE_AUX = 0,
-	QUECTEL_MUX_TYPE_MODEM,
-	QUECTEL_MUX_TYPE_MAX,
-};
-
-struct mux_initialization_data {
-	enum mux_type mux_type;
-	char *chat_debug;
-	const char *n_gsm_key;
-	const char *n_gsm_value;
-};
-
-static const struct mux_initialization_data mux_order_default[] = {
-		{ QUECTEL_MUX_TYPE_MODEM, "Modem: ", "Modem", "/dev/gsmtty1"},
-		{ QUECTEL_MUX_TYPE_AUX, "Aux: ", "Aux", "/dev/gsmtty2"} };
-
-static const struct mux_initialization_data mux_order_ec21[] = {
-		{ QUECTEL_MUX_TYPE_AUX, "Aux: ", "Aux", "/dev/gsmtty1"},
-		{ QUECTEL_MUX_TYPE_MODEM, "Modem: ", "Modem", "/dev/gsmtty2"} };
-
 enum quectel_model {
 	QUECTEL_UNKNOWN,
 	QUECTEL_UC15,
@@ -127,7 +106,6 @@ struct quectel_data {
 	struct l_timeout *init_timeout;
 	size_t init_count;
 	guint init_cmd;
-	const struct mux_initialization_data *mux_order;
 };
 
 struct dbus_hw {
@@ -860,7 +838,6 @@ static GAtChat *create_chat(struct ofono_modem *modem, char *debug)
 static void cmux_gatmux(struct ofono_modem *modem)
 {
 	struct quectel_data *data = ofono_modem_get_data(modem);
-	GAtChat *chat;
 
 	DBG("%p", modem);
 
@@ -876,21 +853,18 @@ static void cmux_gatmux(struct ofono_modem *modem)
 
 	g_at_mux_start(data->mux);
 
-	for (int i = 0; i < QUECTEL_MUX_TYPE_MAX; i++) {
-		chat = create_chat(modem, data->mux_order[i].chat_debug);
-
-		if (!chat) {
-			ofono_error("failed to create %schannel",
-					data->mux_order[i].chat_debug);
-			close_serial(modem);
-			return;
-		}
-
-		if (data->mux_order[i].mux_type == QUECTEL_MUX_TYPE_AUX)
-			data->aux = chat;
-		else
-			data->modem = chat;
+	data->modem = create_chat(modem, "Modem: ");
+	if (!data->modem) {
+		ofono_error("failed to create modem channel");
+		close_serial(modem);
+		return;
+	}
 
+	data->aux = create_chat(modem, "Aux: ");
+	if (!data->aux) {
+		ofono_error("failed to create aux channel");
+		close_serial(modem);
+		return;
 	}
 
 	setup_aux(modem);
@@ -906,9 +880,7 @@ static void mux_ready_cb(struct l_timeout *timeout, void *user_data)
 	DBG("%p", modem);
 
 	/* check if the last (and thus all) virtual gsm tty's are created */
-	ret = stat(ofono_modem_get_string(modem,
-			data->mux_order[QUECTEL_MUX_TYPE_MAX - 1].n_gsm_key),
-			&st);
+	ret = stat(ofono_modem_get_string(modem, "Modem"), &st);
 	if (ret < 0) {
 		if (data->mux_ready_count++ < 5) {
 			/* not ready yet; try again in 100 ms*/
@@ -985,10 +957,8 @@ static void cmux_ngsm(struct ofono_modem *modem)
 	 * the kernel does not yet support mapping the underlying serial device
 	 * to its virtual gsm ttys, so hard-code gsmtty1 gsmtty2 for now
 	 */
-	for (int i = 0; i < QUECTEL_MUX_TYPE_MAX; i++) {
-		ofono_modem_set_string(modem, data->mux_order[i].n_gsm_key,
-					data->mux_order[i].n_gsm_value);
-	}
+	ofono_modem_set_string(modem, "Modem", "/dev/gsmtty1");
+	ofono_modem_set_string(modem, "Aux", "/dev/gsmtty2");
 
 	/* wait for gsmtty devices to appear */
 	if (!l_timeout_create_ms(100, mux_ready_cb, modem, NULL)) {
@@ -1044,8 +1014,6 @@ static void cgmm_cb(int ok, GAtResult *result, void *user_data)
 		return;
 	}
 
-	data->mux_order = mux_order_default;
-
 	if (strcmp(model, "UC15") == 0) {
 		DBG("%p model UC15", modem);
 		data->vendor = OFONO_VENDOR_QUECTEL;
@@ -1062,7 +1030,6 @@ static void cgmm_cb(int ok, GAtResult *result, void *user_data)
 		DBG("%p model EC21", modem);
 		data->vendor = OFONO_VENDOR_QUECTEL;
 		data->model = QUECTEL_EC21;
-		data->mux_order = mux_order_ec21;
 	} else {
 		ofono_warn("%p unknown model: '%s'", modem, model);
 		data->vendor = OFONO_VENDOR_QUECTEL;