uart_send_xchar 720 drivers/tty/serial/serial_core.c uart_send_xchar(tty, STOP_CHAR(tty)); uart_send_xchar 749 drivers/tty/serial/serial_core.c uart_send_xchar(tty, START_CHAR(tty)); uart_send_xchar 2476 drivers/tty/serial/serial_core.c .send_xchar = uart_send_xchar,