From 58362d5be35216f196b4a4d16aa2c6ef938087f0 Mon Sep 17 00:00:00 2001 From: Uwe Kleine-König Date: Sun, 13 Dec 2015 11:30:03 +0100 Subject: serial: imx: implement handshaking using gpios with the mctrl_gpio helper MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Uwe Kleine-König Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/Kconfig | 1 + drivers/tty/serial/imx.c | 89 +++++++++++++++++++++++++++++++++++----------- 2 files changed, 70 insertions(+), 20 deletions(-) (limited to 'drivers') diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 0bdf4d5c7c65..d27a0c62a75f 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -576,6 +576,7 @@ config SERIAL_IMX depends on ARCH_MXC || COMPILE_TEST select SERIAL_CORE select RATIONAL + select SERIAL_MCTRL_GPIO if GPIOLIB help If you have a machine based on a Motorola IMX CPU you can enable its onboard serial port by enabling this option. diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 591f1c26e3e9..9362f54c816c 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -44,6 +44,8 @@ #include #include +#include "serial_mctrl_gpio.h" + /* Register definitions */ #define URXD0 0x0 /* Receiver Register */ #define URTX0 0x40 /* Transmitter Register */ @@ -209,6 +211,8 @@ struct imx_port { struct clk *clk_per; const struct imx_uart_data *devdata; + struct mctrl_gpios *gpios; + /* DMA fields */ unsigned int dma_is_inited:1; unsigned int dma_is_enabled:1; @@ -311,6 +315,26 @@ static void imx_port_ucrs_restore(struct uart_port *port, } #endif +static void imx_port_rts_active(struct imx_port *sport, unsigned long *ucr2) +{ + *ucr2 &= ~UCR2_CTSC; + *ucr2 |= UCR2_CTS; + + mctrl_gpio_set(sport->gpios, sport->port.mctrl | TIOCM_RTS); +} + +static void imx_port_rts_inactive(struct imx_port *sport, unsigned long *ucr2) +{ + *ucr2 &= ~(UCR2_CTSC | UCR2_CTS); + + mctrl_gpio_set(sport->gpios, sport->port.mctrl & ~TIOCM_RTS); +} + +static void imx_port_rts_auto(struct imx_port *sport, unsigned long *ucr2) +{ + *ucr2 |= UCR2_CTSC; +} + /* * interrupts disabled on entry */ @@ -334,9 +358,9 @@ static void imx_stop_tx(struct uart_port *port) readl(port->membase + USR2) & USR2_TXDC) { temp = readl(port->membase + UCR2); if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) - temp &= ~UCR2_CTS; + imx_port_rts_inactive(sport, &temp); else - temp |= UCR2_CTS; + imx_port_rts_active(sport, &temp); writel(temp, port->membase + UCR2); temp = readl(port->membase + UCR4); @@ -378,6 +402,8 @@ static void imx_enable_ms(struct uart_port *port) struct imx_port *sport = (struct imx_port *)port; mod_timer(&sport->timer, jiffies); + + mctrl_gpio_enable_ms(sport->gpios); } static void imx_dma_tx(struct imx_port *sport); @@ -537,14 +563,14 @@ static void imx_start_tx(struct uart_port *port) unsigned long temp; if (port->rs485.flags & SER_RS485_ENABLED) { - /* enable transmitter and shifter empty irq */ temp = readl(port->membase + UCR2); if (port->rs485.flags & SER_RS485_RTS_ON_SEND) - temp &= ~UCR2_CTS; + imx_port_rts_inactive(sport, &temp); else - temp |= UCR2_CTS; + imx_port_rts_active(sport, &temp); writel(temp, port->membase + UCR2); + /* enable transmitter and shifter empty irq */ temp = readl(port->membase + UCR4); temp |= UCR4_TCEN; writel(temp, port->membase + UCR4); @@ -759,9 +785,8 @@ static unsigned int imx_tx_empty(struct uart_port *port) /* * We have a modem side uart, so the meanings of RTS and CTS are inverted. */ -static unsigned int imx_get_mctrl(struct uart_port *port) +static unsigned int imx_get_hwmctrl(struct imx_port *sport) { - struct imx_port *sport = (struct imx_port *)port; unsigned int tmp = TIOCM_DSR; unsigned usr1 = readl(sport->port.membase + USR1); @@ -779,6 +804,16 @@ static unsigned int imx_get_mctrl(struct uart_port *port) return tmp; } +static unsigned int imx_get_mctrl(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + unsigned int ret = imx_get_hwmctrl(sport); + + mctrl_gpio_get(sport->gpios, &ret); + + return ret; +} + static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl) { struct imx_port *sport = (struct imx_port *)port; @@ -801,6 +836,8 @@ static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl) if (mctrl & TIOCM_LOOP) temp |= UTS_LOOP; writel(temp, sport->port.membase + uts_reg(sport)); + + mctrl_gpio_set(sport->gpios, mctrl); } /* @@ -830,7 +867,7 @@ static void imx_mctrl_check(struct imx_port *sport) { unsigned int status, changed; - status = imx_get_mctrl(&sport->port); + status = imx_get_hwmctrl(sport); changed = status ^ sport->old_status; if (changed == 0) @@ -1218,6 +1255,8 @@ static void imx_shutdown(struct uart_port *port) imx_uart_dma_exit(sport); } + mctrl_gpio_disable_ms(sport->gpios); + spin_lock_irqsave(&sport->port.lock, flags); temp = readl(sport->port.membase + UCR2); temp &= ~(UCR2_TXEN); @@ -1295,9 +1334,10 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios, { struct imx_port *sport = (struct imx_port *)port; unsigned long flags; - unsigned int ucr2, old_ucr1, old_ucr2, baud, quot; + unsigned long ucr2, old_ucr1, old_ucr2; + unsigned int baud, quot; unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8; - unsigned int div, ufcr; + unsigned long div, ufcr; unsigned long num, denom; uint64_t tdiv64; @@ -1326,19 +1366,25 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios, * it under manual control and keep transmitter * disabled. */ - if (!(port->rs485.flags & - SER_RS485_RTS_AFTER_SEND)) - ucr2 |= UCR2_CTS; + if (port->rs485.flags & + SER_RS485_RTS_AFTER_SEND) + imx_port_rts_inactive(sport, &ucr2); + else + imx_port_rts_active(sport, &ucr2); } else { - ucr2 |= UCR2_CTSC; + imx_port_rts_auto(sport, &ucr2); } } else { termios->c_cflag &= ~CRTSCTS; } - } else if (port->rs485.flags & SER_RS485_ENABLED) + } else if (port->rs485.flags & SER_RS485_ENABLED) { /* disable transmitter */ - if (!(port->rs485.flags & SER_RS485_RTS_AFTER_SEND)) - ucr2 |= UCR2_CTS; + if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) + imx_port_rts_inactive(sport, &ucr2); + else + imx_port_rts_active(sport, &ucr2); + } + if (termios->c_cflag & CSTOPB) ucr2 |= UCR2_STPB; @@ -1579,11 +1625,10 @@ static int imx_rs485_config(struct uart_port *port, /* disable transmitter */ temp = readl(sport->port.membase + UCR2); - temp &= ~UCR2_CTSC; if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND) - temp &= ~UCR2_CTS; + imx_port_rts_inactive(sport, &temp); else - temp |= UCR2_CTS; + imx_port_rts_active(sport, &temp); writel(temp, sport->port.membase + UCR2); } @@ -1956,6 +2001,10 @@ static int serial_imx_probe(struct platform_device *pdev) sport->timer.function = imx_timeout; sport->timer.data = (unsigned long)sport; + sport->gpios = mctrl_gpio_init(&sport->port, 0); + if (IS_ERR(sport->gpios)) + return PTR_ERR(sport->gpios); + sport->clk_ipg = devm_clk_get(&pdev->dev, "ipg"); if (IS_ERR(sport->clk_ipg)) { ret = PTR_ERR(sport->clk_ipg); -- cgit v1.2.3