tty_write_lock    910 drivers/tty/tty_io.c 	ret = tty_write_lock(tty, file->f_flags & O_NDELAY);
tty_write_lock   1088 drivers/tty/tty_io.c 	if (tty_write_lock(tty, 0) < 0)
tty_write_lock   2387 drivers/tty/tty_io.c 		if (tty_write_lock(tty, 0) < 0)