Messages in this thread | | | Date | Tue, 22 Feb 2022 07:51:39 +0100 | Subject | Re: [PATCH v3 1/9] serial: core: move RS485 configuration tasks from drivers into core | From | Jiri Slaby <> |
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On 22. 02. 22, 2:14, Lino Sanfilippo wrote: > Several drivers that support setting the RS485 configuration via userspace > implement one or more of the following tasks: > > - in case of an invalid RTS configuration (both RTS after send and RTS on > send set or both unset) fall back to enable RTS on send and disable RTS > after send > > - nullify the padding field of the returned serial_rs485 struct > > - copy the configuration into the uart port struct > > - limit RTS delays to 100 ms > > Move these tasks into the serial core to make them generic and to provide > a consistent behaviour among all drivers. > > Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> > --- > drivers/tty/serial/serial_core.c | 29 +++++++++++++++++++++++++++++ > 1 file changed, 29 insertions(+) > > diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c > index 846192a7b4bf..2b3afe038c1c 100644 > --- a/drivers/tty/serial/serial_core.c > +++ b/drivers/tty/serial/serial_core.c > @@ -42,6 +42,11 @@ static struct lock_class_key port_lock_key; > > #define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8) > > +/* > + * Max time with active RTS before/after data is sent. > + */ > +#define RS485_MAX_RTS_DELAY 100 /* msecs */ > + > static void uart_change_speed(struct tty_struct *tty, struct uart_state *state, > struct ktermios *old_termios); > static void uart_wait_until_sent(struct tty_struct *tty, int timeout); > @@ -1282,8 +1287,32 @@ static int uart_set_rs485_config(struct uart_port *port, > if (copy_from_user(&rs485, rs485_user, sizeof(*rs485_user))) > return -EFAULT; > > + /* pick sane settings if the user hasn't */ > + if (!(rs485.flags & SER_RS485_RTS_ON_SEND) == > + !(rs485.flags & SER_RS485_RTS_AFTER_SEND)) { > + pr_warn("invalid RTS setting, using RTS_ON_SEND instead\n");
Can't we have a device prefix here, so that everyone knows what device is affected? Without that, it's not that useful. At least port->name & port->line could be printed. The uart core uses dev_* prints, but prints also line as uport->dev can be NULL sometimes.
Hm, we could introduce uart_print family (to print something like what is in uart_report_port).
thanks, -- js suse labs
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