On Sun, 3 Jul 2022, Lino Sanfilippo wrote: > From: Lino Sanfilippo <l.sanfilippo@xxxxxxxxxx> > > In serial8250_em485_config() the termination GPIO is set with the uart_port > spinlock held. This is an issue if setting the GPIO line can sleep (e.g. > since the concerning GPIO expander is connected via SPI or I2C). > > Fix this by setting the termination line outside of the uart_port spinlock > in the serial core and using gpiod_set_value_cansleep() which instead of > gpiod_set_value() allows to sleep. > > Beside fixing the termination GPIO line setting for the 8250 driver this > change also makes setting the termination GPIO generic for all UART > drivers. > > Signed-off-by: Lino Sanfilippo <l.sanfilippo@xxxxxxxxxx> > --- > drivers/tty/serial/8250/8250_port.c | 3 --- > drivers/tty/serial/serial_core.c | 12 ++++++++++++ > 2 files changed, 12 insertions(+), 3 deletions(-) > > diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c > index ed2a606f2da7..72252d956f17 100644 > --- a/drivers/tty/serial/8250/8250_port.c > +++ b/drivers/tty/serial/8250/8250_port.c > @@ -676,9 +676,6 @@ int serial8250_em485_config(struct uart_port *port, struct ktermios *termios, > rs485->flags &= ~SER_RS485_RTS_AFTER_SEND; > } > > - gpiod_set_value(port->rs485_term_gpio, > - rs485->flags & SER_RS485_TERMINATE_BUS); > - I sent a series to make .rs485_supported per uart_port and properly set SER_RS485_TERMINATE_BUS according to DT config. With that series added first, SER_RS485_TERMINATE_BUS should also be removed from serial8250_em485_supported so that serial core can properly manage it all. -- i.
