diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c
index f2c4bb709747..84f8c106e5e9 100644
--- a/drivers/usb/serial/mos7840.c
+++ b/drivers/usb/serial/mos7840.c
@@ -222,7 +222,6 @@ struct moschip_port {
 	__u8 shadowMCR;		/* last MCR value received */
 	char open;
 	char open_ports;
-	char zombie;
 	wait_queue_head_t wait_chase;	/* for handling sleeping while waiting for chase to finish */
 	wait_queue_head_t delta_msr_wait;	/* for handling sleeping while waiting for msr change to happen */
 	int delta_msr_cond;
@@ -674,14 +673,7 @@ static void mos7840_interrupt_callback(struct urb *urb)
 					wreg = MODEM_STATUS_REGISTER;
 					break;
 				}
-				spin_lock(&mos7840_port->pool_lock);
-				if (!mos7840_port->zombie) {
-					rv = mos7840_get_reg(mos7840_port, wval, wreg, &Data);
-				} else {
-					spin_unlock(&mos7840_port->pool_lock);
-					return;
-				}
-				spin_unlock(&mos7840_port->pool_lock);
+				rv = mos7840_get_reg(mos7840_port, wval, wreg, &Data);
 			}
 		}
 	}
@@ -2598,9 +2590,6 @@ static void mos7840_disconnect(struct usb_serial *serial)
 	for (i = 0; i < serial->num_ports; ++i) {
 		mos7840_port = mos7840_get_port_private(serial->port[i]);
 		if (mos7840_port) {
-			spin_lock_irqsave(&mos7840_port->pool_lock, flags);
-			mos7840_port->zombie = 1;
-			spin_unlock_irqrestore(&mos7840_port->pool_lock, flags);
 			usb_kill_urb(mos7840_port->control_urb);
 		}
 	}