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charset="utf-8" From: Bartosz Golaszewski Since commit 1f2bcb8c8ccd ("gpio: protect the descriptor label with SRCU") gpiod_set_consumer_name() calls synchronize_srcu() which led to a "sleeping in atomic context" smatch warning. This function (along with gpiod_get/put() and all other GPIO APIs apart from gpiod_get/set_value() and gpiod_direction_input/output()) should have never been called with a spinlock taken. We're only fixing this now as GPIOLIB has been rebuilt to use SRCU for access serialization which uncovered this problem. Move the calls to gpiod_get/put() outside the spinlock critical section. Reported-by: Dan Carpenter Closes: https://lore.kernel.org/linux-gpio/deee1438-efc1-47c4-8d80-0ab2cf01= d60a@moroto.mountain/ Signed-off-by: Bartosz Golaszewski Reviewed-by: Linus Walleij --- drivers/tty/serial/st-asc.c | 40 ++++++++++++++++++++----------------- 1 file changed, 22 insertions(+), 18 deletions(-) diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c index bbb5595d7e24..52a20277df98 100644 --- a/drivers/tty/serial/st-asc.c +++ b/drivers/tty/serial/st-asc.c @@ -467,6 +467,7 @@ static void asc_set_termios(struct uart_port *port, str= uct ktermios *termios, struct asc_port *ascport =3D to_asc_port(port); struct gpio_desc *gpiod; unsigned int baud; + bool manual_rts; u32 ctrl_val; tcflag_t cflag; unsigned long flags; @@ -517,26 +518,12 @@ static void asc_set_termios(struct uart_port *port, s= truct ktermios *termios, ctrl_val |=3D ASC_CTL_CTSENABLE; =20 /* If flow-control selected, stop handling RTS manually */ - if (ascport->rts) { - devm_gpiod_put(port->dev, ascport->rts); - ascport->rts =3D NULL; - - pinctrl_select_state(ascport->pinctrl, - ascport->states[DEFAULT]); - } + if (ascport->rts) + manual_rts =3D false; } else { /* If flow-control disabled, it's safe to handle RTS manually */ - if (!ascport->rts && ascport->states[NO_HW_FLOWCTRL]) { - pinctrl_select_state(ascport->pinctrl, - ascport->states[NO_HW_FLOWCTRL]); - - gpiod =3D devm_gpiod_get(port->dev, "rts", GPIOD_OUT_LOW); - if (!IS_ERR(gpiod)) { - gpiod_set_consumer_name(gpiod, - port->dev->of_node->name); - ascport->rts =3D gpiod; - } - } + if (!ascport->rts && ascport->states[NO_HW_FLOWCTRL]) + manual_rts =3D true; } =20 if ((baud < 19200) && !ascport->force_m1) { @@ -595,6 +582,23 @@ static void asc_set_termios(struct uart_port *port, st= ruct ktermios *termios, asc_out(port, ASC_CTL, (ctrl_val | ASC_CTL_RUN)); =20 uart_port_unlock_irqrestore(port, flags); + + if (manual_rts) { + pinctrl_select_state(ascport->pinctrl, + ascport->states[NO_HW_FLOWCTRL]); + + gpiod =3D devm_gpiod_get(port->dev, "rts", GPIOD_OUT_LOW); + if (!IS_ERR(gpiod)) { + gpiod_set_consumer_name(gpiod, + port->dev->of_node->name); + ascport->rts =3D gpiod; + } else { + devm_gpiod_put(port->dev, ascport->rts); + ascport->rts =3D NULL; + pinctrl_select_state(ascport->pinctrl, + ascport->states[DEFAULT]); + } + } } =20 static const char *asc_type(struct uart_port *port) --=20 2.40.1