diff --git a/drivers/usb/gadget/function/f_cdev.c b/drivers/usb/gadget/function/f_cdev.c
index 9357949a1525..481783ea6968 100644
--- a/drivers/usb/gadget/function/f_cdev.c
+++ b/drivers/usb/gadget/function/f_cdev.c
@@ -1617,6 +1617,7 @@ static long f_cdev_ioctl(struct file *fp, unsigned int cmd,
 	int i = 0;
 	uint32_t val;
 	struct f_cdev *port;
+	unsigned long flags;
 
 	port = fp->private_data;
 	if (!port) {
@@ -1638,11 +1639,13 @@ static long f_cdev_ioctl(struct file *fp, unsigned int cmd,
 		break;
 	case TIOCMGET:
 		pr_debug("TIOCMGET on port(%s)%pK\n", port->name, port);
+		spin_lock_irqsave(&port->port_lock, flags);
 		ret = f_cdev_tiocmget(port);
 		if (ret >= 0) {
 			ret = put_user(ret, (uint32_t *)arg);
 			port->cbits_updated = false;
 		}
+		spin_unlock_irqrestore(&port->port_lock, flags);
 		break;
 	default:
 		pr_err("Received cmd:%d not supported\n", cmd);
@@ -1658,6 +1661,7 @@ static void usb_cser_notify_modem(void *fport, int ctrl_bits)
 	int temp;
 	struct f_cdev *port = fport;
 	struct cserial *cser;
+	unsigned long flags;
 
 	cser = &port->port_usb;
 	if (!port) {
@@ -1672,6 +1676,7 @@ static void usb_cser_notify_modem(void *fport, int ctrl_bits)
 	if (temp == port->cbits_to_modem)
 		return;
 
+	spin_lock_irqsave(&port->port_lock, flags);
 	port->cbits_to_modem = temp;
 	port->cbits_updated = true;
 
@@ -1686,6 +1691,7 @@ static void usb_cser_notify_modem(void *fport, int ctrl_bits)
 			cser->send_modem_ctrl_bits(cser, cbits_to_laptop);
 	}
 
+	spin_unlock_irqrestore(&port->port_lock, flags);
 	wake_up(&port->read_wq);
 }