From: Marek Vasut marex@denx.de
[ Upstream commit 3bcea529b295a993b1b05db63f245ae8030c5acf ]
Pull out the GPIO RTS enable and disable handling into separate function. Limit the scope of GPIO RTS toggling only to GPIO emulated RS485 too.
Signed-off-by: Marek Vasut marex@denx.de Cc: Alexandre Torgue alexandre.torgue@foss.st.com Cc: Erwan Le Ray erwan.leray@foss.st.com Cc: Greg Kroah-Hartman gregkh@linuxfoundation.org Cc: Jean Philippe Romain jean-philippe.romain@foss.st.com Cc: Valentin Caron valentin.caron@foss.st.com Cc: linux-arm-kernel@lists.infradead.org Cc: linux-stm32@st-md-mailman.stormreply.com To: linux-serial@vger.kernel.org Link: https://lore.kernel.org/r/20220430162845.244655-1-marex@denx.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/tty/serial/stm32-usart.c | 61 ++++++++++++++++++++------------ 1 file changed, 38 insertions(+), 23 deletions(-)
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index fc166cc2c856..f2cef5f7ae5a 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -325,6 +325,42 @@ static void stm32_usart_tx_interrupt_disable(struct uart_port *port) stm32_usart_clr_bits(port, ofs->cr1, USART_CR1_TXEIE); }
+static void stm32_usart_rs485_rts_enable(struct uart_port *port) +{ + struct stm32_port *stm32_port = to_stm32_port(port); + struct serial_rs485 *rs485conf = &port->rs485; + + if (stm32_port->hw_flow_control || + !(rs485conf->flags & SER_RS485_ENABLED)) + return; + + if (rs485conf->flags & SER_RS485_RTS_ON_SEND) { + mctrl_gpio_set(stm32_port->gpios, + stm32_port->port.mctrl | TIOCM_RTS); + } else { + mctrl_gpio_set(stm32_port->gpios, + stm32_port->port.mctrl & ~TIOCM_RTS); + } +} + +static void stm32_usart_rs485_rts_disable(struct uart_port *port) +{ + struct stm32_port *stm32_port = to_stm32_port(port); + struct serial_rs485 *rs485conf = &port->rs485; + + if (stm32_port->hw_flow_control || + !(rs485conf->flags & SER_RS485_ENABLED)) + return; + + if (rs485conf->flags & SER_RS485_RTS_ON_SEND) { + mctrl_gpio_set(stm32_port->gpios, + stm32_port->port.mctrl & ~TIOCM_RTS); + } else { + mctrl_gpio_set(stm32_port->gpios, + stm32_port->port.mctrl | TIOCM_RTS); + } +} + static void stm32_usart_transmit_chars_pio(struct uart_port *port) { struct stm32_port *stm32_port = to_stm32_port(port); @@ -566,41 +602,20 @@ static void stm32_usart_disable_ms(struct uart_port *port) /* Transmit stop */ static void stm32_usart_stop_tx(struct uart_port *port) { - struct stm32_port *stm32_port = to_stm32_port(port); - struct serial_rs485 *rs485conf = &port->rs485; - stm32_usart_tx_interrupt_disable(port);
- if (rs485conf->flags & SER_RS485_ENABLED) { - if (rs485conf->flags & SER_RS485_RTS_ON_SEND) { - mctrl_gpio_set(stm32_port->gpios, - stm32_port->port.mctrl & ~TIOCM_RTS); - } else { - mctrl_gpio_set(stm32_port->gpios, - stm32_port->port.mctrl | TIOCM_RTS); - } - } + stm32_usart_rs485_rts_disable(port); }
/* There are probably characters waiting to be transmitted. */ static void stm32_usart_start_tx(struct uart_port *port) { - struct stm32_port *stm32_port = to_stm32_port(port); - struct serial_rs485 *rs485conf = &port->rs485; struct circ_buf *xmit = &port->state->xmit;
if (uart_circ_empty(xmit) && !port->x_char) return;
- if (rs485conf->flags & SER_RS485_ENABLED) { - if (rs485conf->flags & SER_RS485_RTS_ON_SEND) { - mctrl_gpio_set(stm32_port->gpios, - stm32_port->port.mctrl | TIOCM_RTS); - } else { - mctrl_gpio_set(stm32_port->gpios, - stm32_port->port.mctrl & ~TIOCM_RTS); - } - } + stm32_usart_rs485_rts_enable(port);
stm32_usart_transmit_chars(port); }