Merge "usb: u_serial: Fix spin lockup issue"

		port->read_started--;

	}

	/* Push from tty to ldisc; without low_latency set this is handled by

	 * a workqueue, so we won't get callbacks and can hold port_lock

	/*

	 * Push from tty to ldisc:

	 * With low_latency set to 0:

	 * this is handled by a workqueue, so we won't get callbacks

	 * (tty->ops->flush_chars i.e. gs_flush_chars) and can hold

	 * port_lock.

	 * With low_latency set to 1:

	 * gs_flush_chars (tty->ops->flush_chars) is called synchronosly

	 * with port_lock held. Hence we need to release it temporarily

	 * to avoid recursive spinlock.

	 */

	if (do_push)

	if (do_push) {

		if (port->port.low_latency)

			spin_unlock(&port->port_lock);

		tty_flip_buffer_push(&port->port);

		if (port->port.low_latency)

			spin_lock(&port->port_lock);

	}

	/* We want our data queue to become empty ASAP, keeping data

	 * in the tty and ldisc (not here).  If we couldn't push any