diff --git a/[refs] b/[refs]
index d573909688b6..c06cb3d67ce7 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c0f5ecee4e741667b2493c742b60b6218d40b3aa
+refs/heads/master: 3f8bc5e4da29c7e05edeca6b475abb4fb01a5a13
diff --git a/trunk/drivers/usb/serial/qcserial.c b/trunk/drivers/usb/serial/qcserial.c
index 24662547dc5b..59b32b782126 100644
--- a/trunk/drivers/usb/serial/qcserial.c
+++ b/trunk/drivers/usb/serial/qcserial.c
@@ -197,12 +197,15 @@ static int qcprobe(struct usb_serial *serial, const struct usb_device_id *id)
 
 	if (is_gobi1k) {
 		/* Gobi 1K USB layout:
-		 * 0: serial port (doesn't respond)
+		 * 0: DM/DIAG (use libqcdm from ModemManager for communication)
 		 * 1: serial port (doesn't respond)
 		 * 2: AT-capable modem port
 		 * 3: QMI/net
 		 */
-		if (ifnum == 2)
+		if (ifnum == 0) {
+			dev_dbg(dev, "Gobi 1K DM/DIAG interface found\n");
+			altsetting = 1;
+		} else if (ifnum == 2)
 			dev_dbg(dev, "Modem port found\n");
 		else
 			altsetting = -1;