Since commit edc6afc54968 ("tty: switch to ktermios and new framework")
termios speed is no longer stored only in c_cflag member but also in new
additional c_ispeed and c_ospeed members. If BOTHER flag is set in c_cflag
then termios speed is stored only in these new members.
Since commit 027b57170bf8 ("serial: core: Fix initializing and restoring
termios speed") termios speed is available also in struct console.
So properly restore also c_ispeed and c_ospeed members after suspend to fix
restoring termios speed which is not represented by Bnnn constant.
Fixes: 4516d50aabed ("serial: 8250: Use canary to restart console after suspend")
Signed-off-by: Pali Rohár <[email protected]>
---
drivers/tty/serial/8250/8250_port.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 39b35a61958c..441f317c55af 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -3314,8 +3314,13 @@ static void serial8250_console_restore(struct uart_8250_port *up)
unsigned int baud, quot, frac = 0;
termios.c_cflag = port->cons->cflag;
- if (port->state->port.tty && termios.c_cflag == 0)
+ termios.c_ispeed = port->cons->ispeed;
+ termios.c_ospeed = port->cons->ospeed;
+ if (port->state->port.tty && termios.c_cflag == 0) {
termios.c_cflag = port->state->port.tty->termios.c_cflag;
+ termios.c_ispeed = port->state->port.tty->termios.c_ispeed;
+ termios.c_ospeed = port->state->port.tty->termios.c_ospeed;
+ }
baud = serial8250_get_baud_rate(port, &termios, NULL);
quot = serial8250_get_divisor(port, baud, &frac);
--
2.20.1
On 24. 09. 22, 12:43, Pali Rohár wrote:
> Since commit edc6afc54968 ("tty: switch to ktermios and new framework")
> termios speed is no longer stored only in c_cflag member but also in new
> additional c_ispeed and c_ospeed members. If BOTHER flag is set in c_cflag
> then termios speed is stored only in these new members.
>
> Since commit 027b57170bf8 ("serial: core: Fix initializing and restoring
> termios speed") termios speed is available also in struct console.
>
> So properly restore also c_ispeed and c_ospeed members after suspend to fix
> restoring termios speed which is not represented by Bnnn constant.
>
> Fixes: 4516d50aabed ("serial: 8250: Use canary to restart console after suspend")
> Signed-off-by: Pali Rohár <[email protected]>
> ---
> drivers/tty/serial/8250/8250_port.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
> index 39b35a61958c..441f317c55af 100644
> --- a/drivers/tty/serial/8250/8250_port.c
> +++ b/drivers/tty/serial/8250/8250_port.c
> @@ -3314,8 +3314,13 @@ static void serial8250_console_restore(struct uart_8250_port *up)
> unsigned int baud, quot, frac = 0;
>
> termios.c_cflag = port->cons->cflag;
> - if (port->state->port.tty && termios.c_cflag == 0)
> + termios.c_ispeed = port->cons->ispeed;
> + termios.c_ospeed = port->cons->ospeed;
> + if (port->state->port.tty && termios.c_cflag == 0) {
I don't currently know how safe it is to assume port->state->port.tty
cannot change between the test above and the dereferences below.
In anyway, you should cache it as it is used 4 times now. It would make
the code definitely more readable.
> termios.c_cflag = port->state->port.tty->termios.c_cflag;
> + termios.c_ispeed = port->state->port.tty->termios.c_ispeed;
> + termios.c_ospeed = port->state->port.tty->termios.c_ospeed;
> + }
>
> baud = serial8250_get_baud_rate(port, &termios, NULL);
> quot = serial8250_get_divisor(port, baud, &frac);
--
js
suse labs