Commit 3f582b8c authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Greg Kroah-Hartman

serial: fix termios settings in open

Move termios initialization in open into uart_dtr_rts to make sure
it always gets called when necessary. Based on a suggestion from
Alan Cox.

Alan writes:
Ok this sort of makes sense. Something isn't getting initialised and both
getty and minicom will do a termios set which is sorting it out.
This is occurring because the generic block_til_ready sets
ASYNCB_NORMAL_ACTIVE so the termios updating gets skipped.

This patch should cure it and then we can think about doing it more
elegantly by getting the serial layer to use tty_port_open, kfifo and
the like and removing the tons of repeated crap in all the drivers.
Signed-off-by: default avatarArnd Bergmann <>
Reported-by: default avatarTony Luck <>
Cc: Alan Cox <>
Cc: Tony Luck <>
Signed-off-by: default avatarGreg Kroah-Hartman <>
parent 74c21077
......@@ -1520,8 +1520,16 @@ static void uart_dtr_rts(struct tty_port *port, int onoff)
struct uart_state *state = container_of(port, struct uart_state, port);
struct uart_port *uport = state->uart_port;
if (onoff)
if (onoff) {
uart_set_mctrl(uport, TIOCM_DTR | TIOCM_RTS);
* If this is the first open to succeed,
* adjust things to suit.
if (!test_and_set_bit(ASYNCB_NORMAL_ACTIVE, &port->flags))
uart_update_termios(port->tty, state);
uart_clear_mctrl(uport, TIOCM_DTR | TIOCM_RTS);
......@@ -1636,15 +1644,6 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
if (retval == 0)
retval = tty_port_block_til_ready(port, tty, filp);
* If this is the first open to succeed, adjust things to suit.
if (retval == 0 && !(port->flags & ASYNC_NORMAL_ACTIVE)) {
set_bit(ASYNCB_NORMAL_ACTIVE, &port->flags);
uart_update_termios(tty, state);
return retval;
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