serial: imx: implement handshaking using gpios with the mctrl_gpio helper (58362d5b) · Commits · e / devices / android_kernel_teracube_emerald

drivers/tty/serial/Kconfig

+1 −0

Original line number	Original line	Diff line number	Diff line
	@@ -576,6 +576,7 @@ config SERIAL_IMX
	depends on ARCH_MXC \|\| COMPILE_TEST		depends on ARCH_MXC \|\| COMPILE_TEST
	select SERIAL_CORE		select SERIAL_CORE
	select RATIONAL		select RATIONAL
			select SERIAL_MCTRL_GPIO if GPIOLIB
	help		help
	If you have a machine based on a Motorola IMX CPU you		If you have a machine based on a Motorola IMX CPU you
	can enable its onboard serial port by enabling this option.		can enable its onboard serial port by enabling this option.

drivers/tty/serial/imx.c

+69 −20

Original line number	Original line	Diff line number	Diff line
	@@ -44,6 +44,8 @@
	#include <linux/platform_data/serial-imx.h>		#include <linux/platform_data/serial-imx.h>
	#include <linux/platform_data/dma-imx.h>		#include <linux/platform_data/dma-imx.h>

			#include "serial_mctrl_gpio.h"

	/* Register definitions */		/* Register definitions */
	#define URXD0 0x0 /* Receiver Register */		#define URXD0 0x0 /* Receiver Register */
	#define URTX0 0x40 /* Transmitter Register */		#define URTX0 0x40 /* Transmitter Register */
	@@ -209,6 +211,8 @@ struct imx_port {
	struct clk *clk_per;		struct clk *clk_per;
	const struct imx_uart_data *devdata;		const struct imx_uart_data *devdata;

			struct mctrl_gpios *gpios;

	/* DMA fields */		/* DMA fields */
	unsigned int dma_is_inited:1;		unsigned int dma_is_inited:1;
	unsigned int dma_is_enabled:1;		unsigned int dma_is_enabled:1;
	@@ -311,6 +315,26 @@ static void imx_port_ucrs_restore(struct uart_port *port,
	}		}
	#endif		#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		* interrupts disabled on entry
	*/		*/
	@@ -334,9 +358,9 @@ static void imx_stop_tx(struct uart_port *port)
	readl(port->membase + USR2) & USR2_TXDC) {		readl(port->membase + USR2) & USR2_TXDC) {
	temp = readl(port->membase + UCR2);		temp = readl(port->membase + UCR2);
	if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND)		if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND)
	temp &= ~UCR2_CTS;		imx_port_rts_inactive(sport, &temp);
	else		else
	temp \|= UCR2_CTS;		imx_port_rts_active(sport, &temp);
	writel(temp, port->membase + UCR2);		writel(temp, port->membase + UCR2);

	temp = readl(port->membase + UCR4);		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;		struct imx_port sport = (struct imx_port )port;

	mod_timer(&sport->timer, jiffies);		mod_timer(&sport->timer, jiffies);

			mctrl_gpio_enable_ms(sport->gpios);
	}		}

	static void imx_dma_tx(struct imx_port *sport);		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;		unsigned long temp;

	if (port->rs485.flags & SER_RS485_ENABLED) {		if (port->rs485.flags & SER_RS485_ENABLED) {
	/* enable transmitter and shifter empty irq */
	temp = readl(port->membase + UCR2);		temp = readl(port->membase + UCR2);
	if (port->rs485.flags & SER_RS485_RTS_ON_SEND)		if (port->rs485.flags & SER_RS485_RTS_ON_SEND)
	temp &= ~UCR2_CTS;		imx_port_rts_inactive(sport, &temp);
	else		else
	temp \|= UCR2_CTS;		imx_port_rts_active(sport, &temp);
	writel(temp, port->membase + UCR2);		writel(temp, port->membase + UCR2);

			/* enable transmitter and shifter empty irq */
	temp = readl(port->membase + UCR4);		temp = readl(port->membase + UCR4);
	temp \|= UCR4_TCEN;		temp \|= UCR4_TCEN;
	writel(temp, port->membase + UCR4);		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.		* 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 int tmp = TIOCM_DSR;
	unsigned usr1 = readl(sport->port.membase + USR1);		unsigned usr1 = readl(sport->port.membase + USR1);

	@@ -779,6 +804,16 @@ static unsigned int imx_get_mctrl(struct uart_port *port)
	return tmp;		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)		static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl)
	{		{
	struct imx_port sport = (struct imx_port )port;		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)		if (mctrl & TIOCM_LOOP)
	temp \|= UTS_LOOP;		temp \|= UTS_LOOP;
	writel(temp, sport->port.membase + uts_reg(sport));		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;		unsigned int status, changed;

	status = imx_get_mctrl(&sport->port);		status = imx_get_hwmctrl(sport);
	changed = status ^ sport->old_status;		changed = status ^ sport->old_status;

	if (changed == 0)		if (changed == 0)
	@@ -1218,6 +1255,8 @@ static void imx_shutdown(struct uart_port *port)
	imx_uart_dma_exit(sport);		imx_uart_dma_exit(sport);
	}		}

			mctrl_gpio_disable_ms(sport->gpios);

	spin_lock_irqsave(&sport->port.lock, flags);		spin_lock_irqsave(&sport->port.lock, flags);
	temp = readl(sport->port.membase + UCR2);		temp = readl(sport->port.membase + UCR2);
	temp &= ~(UCR2_TXEN);		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;		struct imx_port sport = (struct imx_port )port;
	unsigned long flags;		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 old_csize = old ? old->c_cflag & CSIZE : CS8;
	unsigned int div, ufcr;		unsigned long div, ufcr;
	unsigned long num, denom;		unsigned long num, denom;
	uint64_t tdiv64;		uint64_t tdiv64;

	@@ -1326,19 +1366,25 @@ imx_set_termios(struct uart_port port, struct ktermios termios,
	* it under manual control and keep transmitter		* it under manual control and keep transmitter
	* disabled.		* disabled.
	*/		*/
	if (!(port->rs485.flags &		if (port->rs485.flags &
	SER_RS485_RTS_AFTER_SEND))		SER_RS485_RTS_AFTER_SEND)
	ucr2 \|= UCR2_CTS;		imx_port_rts_inactive(sport, &ucr2);
			else
			imx_port_rts_active(sport, &ucr2);
	} else {		} else {
	ucr2 \|= UCR2_CTSC;		imx_port_rts_auto(sport, &ucr2);
	}		}
	} else {		} else {
	termios->c_cflag &= ~CRTSCTS;		termios->c_cflag &= ~CRTSCTS;
	}		}
	} else if (port->rs485.flags & SER_RS485_ENABLED)		} else if (port->rs485.flags & SER_RS485_ENABLED) {
	/* disable transmitter */		/* disable transmitter */
	if (!(port->rs485.flags & SER_RS485_RTS_AFTER_SEND))		if (port->rs485.flags & SER_RS485_RTS_AFTER_SEND)
	ucr2 \|= UCR2_CTS;		imx_port_rts_inactive(sport, &ucr2);
			else
			imx_port_rts_active(sport, &ucr2);
			}


	if (termios->c_cflag & CSTOPB)		if (termios->c_cflag & CSTOPB)
	ucr2 \|= UCR2_STPB;		ucr2 \|= UCR2_STPB;
	@@ -1579,11 +1625,10 @@ static int imx_rs485_config(struct uart_port *port,

	/* disable transmitter */		/* disable transmitter */
	temp = readl(sport->port.membase + UCR2);		temp = readl(sport->port.membase + UCR2);
	temp &= ~UCR2_CTSC;
	if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND)		if (rs485conf->flags & SER_RS485_RTS_AFTER_SEND)
	temp &= ~UCR2_CTS;		imx_port_rts_inactive(sport, &temp);
	else		else
	temp \|= UCR2_CTS;		imx_port_rts_active(sport, &temp);
	writel(temp, sport->port.membase + UCR2);		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.function = imx_timeout;
	sport->timer.data = (unsigned long)sport;		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");		sport->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
	if (IS_ERR(sport->clk_ipg)) {		if (IS_ERR(sport->clk_ipg)) {
	ret = PTR_ERR(sport->clk_ipg);		ret = PTR_ERR(sport->clk_ipg);