diff options
Diffstat (limited to 'drivers/tty/serial/stm32-usart.c')
| -rw-r--r-- | drivers/tty/serial/stm32-usart.c | 74 |
1 files changed, 67 insertions, 7 deletions
diff --git a/drivers/tty/serial/stm32-usart.c b/drivers/tty/serial/stm32-usart.c index 5e93e8d40f59..8602ff357321 100644 --- a/drivers/tty/serial/stm32-usart.c +++ b/drivers/tty/serial/stm32-usart.c @@ -31,6 +31,7 @@ #include <linux/tty_flip.h> #include <linux/tty.h> +#include "serial_mctrl_gpio.h" #include "stm32-usart.h" static void stm32_stop_tx(struct uart_port *port); @@ -158,9 +159,7 @@ static int stm32_init_rs485(struct uart_port *port, if (!pdev->dev.of_node) return -ENODEV; - uart_get_rs485_mode(&pdev->dev, rs485conf); - - return 0; + return uart_get_rs485_mode(port); } static int stm32_pending_rx(struct uart_port *port, u32 *sr, int *last_res, @@ -510,12 +509,29 @@ static void stm32_set_mctrl(struct uart_port *port, unsigned int mctrl) stm32_set_bits(port, ofs->cr3, USART_CR3_RTSE); else stm32_clr_bits(port, ofs->cr3, USART_CR3_RTSE); + + mctrl_gpio_set(stm32_port->gpios, mctrl); } static unsigned int stm32_get_mctrl(struct uart_port *port) { + struct stm32_port *stm32_port = to_stm32_port(port); + unsigned int ret; + /* This routine is used to get signals of: DCD, DSR, RI, and CTS */ - return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; + ret = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS; + + return mctrl_gpio_get(stm32_port->gpios, &ret); +} + +static void stm32_enable_ms(struct uart_port *port) +{ + mctrl_gpio_enable_ms(to_stm32_port(port)->gpios); +} + +static void stm32_disable_ms(struct uart_port *port) +{ + mctrl_gpio_disable_ms(to_stm32_port(port)->gpios); } /* Transmit stop */ @@ -626,6 +642,9 @@ static void stm32_shutdown(struct uart_port *port) u32 val, isr; int ret; + /* Disable modem control interrupts */ + stm32_disable_ms(port); + val = USART_CR1_TXEIE | USART_CR1_TE; val |= stm32_port->cr1_irq | USART_CR1_RE; val |= BIT(cfg->uart_enable_bit); @@ -764,6 +783,12 @@ static void stm32_set_termios(struct uart_port *port, struct ktermios *termios, cr3 |= USART_CR3_CTSE | USART_CR3_RTSE; } + /* Handle modem control interrupts */ + if (UART_ENABLE_MS(port, termios->c_cflag)) + stm32_enable_ms(port); + else + stm32_disable_ms(port); + usartdiv = DIV_ROUND_CLOSEST(port->uartclk, baud); /* @@ -898,6 +923,7 @@ static const struct uart_ops stm32_uart_ops = { .throttle = stm32_throttle, .unthrottle = stm32_unthrottle, .stop_rx = stm32_stop_rx, + .enable_ms = stm32_enable_ms, .break_ctl = stm32_break_ctl, .startup = stm32_startup, .shutdown = stm32_shutdown, @@ -931,7 +957,9 @@ static int stm32_init_port(struct stm32_port *stm32port, port->rs485_config = stm32_config_rs485; - stm32_init_rs485(port, pdev); + ret = stm32_init_rs485(port, pdev); + if (ret) + return ret; if (stm32port->info->cfg.has_wakeup) { stm32port->wakeirq = platform_get_irq(pdev, 1); @@ -960,11 +988,32 @@ static int stm32_init_port(struct stm32_port *stm32port, stm32port->port.uartclk = clk_get_rate(stm32port->clk); if (!stm32port->port.uartclk) { - clk_disable_unprepare(stm32port->clk); ret = -EINVAL; + goto err_clk; + } + + stm32port->gpios = mctrl_gpio_init(&stm32port->port, 0); + if (IS_ERR(stm32port->gpios)) { + ret = PTR_ERR(stm32port->gpios); + goto err_clk; + } + + /* Both CTS/RTS gpios and "st,hw-flow-ctrl" should not be specified */ + if (stm32port->hw_flow_control) { + if (mctrl_gpio_to_gpiod(stm32port->gpios, UART_GPIO_CTS) || + mctrl_gpio_to_gpiod(stm32port->gpios, UART_GPIO_RTS)) { + dev_err(&pdev->dev, "Conflicting RTS/CTS config\n"); + ret = -EINVAL; + goto err_clk; + } } return ret; + +err_clk: + clk_disable_unprepare(stm32port->clk); + + return ret; } static struct stm32_port *stm32_of_get_stm32_port(struct platform_device *pdev) @@ -1375,7 +1424,18 @@ static int __maybe_unused stm32_serial_suspend(struct device *dev) else stm32_serial_enable_wakeup(port, false); - pinctrl_pm_select_sleep_state(dev); + /* + * When "no_console_suspend" is enabled, keep the pinctrl default state + * and rely on bootloader stage to restore this state upon resume. + * Otherwise, apply the idle or sleep states depending on wakeup + * capabilities. + */ + if (console_suspend_enabled || !uart_console(port)) { + if (device_may_wakeup(dev)) + pinctrl_pm_select_idle_state(dev); + else + pinctrl_pm_select_sleep_state(dev); + } return 0; } |