Re: [PATCH v2 2/9] serial: core, 8250: set RS485 termination gpio in serial core
From: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Date: 2022-07-04 15:14:18
Also in:
linux-devicetree, linux-serial, lkml
On 04.07.22 11:51, Ilpo Järvinen wrote:
On Sun, 3 Jul 2022, Lino Sanfilippo wrote:quoted
From: Lino Sanfilippo <redacted> 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 <redacted> --- 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.
Ok, I will rebase the next version of my patches on your series then. Regards, Lino _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel