From 3bcea529b295a993b1b05db63f245ae8030c5acf Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Sat, 30 Apr 2022 18:28:44 +0200 Subject: [PATCH] serial: stm32: Factor out GPIO RTS toggling into separate function 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 Cc: Alexandre Torgue Cc: Erwan Le Ray Cc: Greg Kroah-Hartman Cc: Jean Philippe Romain Cc: Valentin Caron 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 --- drivers/tty/serial/stm32-usart.c | 59 ++++++++++++++++++++++++++-------------- 1 file changed, 38 insertions(+), 21 deletions(-) diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index f75691e..224f359 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -442,6 +442,42 @@ 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); @@ -713,43 +749,24 @@ static void stm32_usart_disable_ms(struct uart_port *port) 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; const struct stm32_usart_offsets *ofs = &stm32_port->info->ofs; stm32_usart_tx_interrupt_disable(port); if (stm32_usart_tx_dma_started(stm32_port) && stm32_usart_tx_dma_enabled(stm32_port)) stm32_usart_clr_bits(port, ofs->cr3, USART_CR3_DMAT); - 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); } -- 2.7.4