[mirror_ubuntu-artful-kernel.git] / drivers / tty / serial / serial_ks8695.c

/*
 *  Driver for KS8695 serial ports
 *
 *  Based on drivers/serial/serial_amba.c, by Kam Lee.
 *
 *  Copyright 2002-2005 Micrel Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 */
#include <linux/module.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/serial.h>
#include <linux/console.h>
#include <linux/sysrq.h>
#include <linux/device.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/mach/irq.h>

#include <mach/regs-uart.h>
#include <mach/regs-irq.h>

#if defined(CONFIG_SERIAL_KS8695_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif

#include <linux/serial_core.h>


#define SERIAL_KS8695_MAJOR	204
#define SERIAL_KS8695_MINOR	16
#define SERIAL_KS8695_DEVNAME	"ttyAM"

#define SERIAL_KS8695_NR	1

/*
 * Access macros for the KS8695 UART
 */
#define UART_GET_CHAR(p)	(__raw_readl((p)->membase + KS8695_URRB) & 0xFF)
#define UART_PUT_CHAR(p, c)	__raw_writel((c), (p)->membase + KS8695_URTH)
#define UART_GET_FCR(p)		__raw_readl((p)->membase + KS8695_URFC)
#define UART_PUT_FCR(p, c)	__raw_writel((c), (p)->membase + KS8695_URFC)
#define UART_GET_MSR(p)		__raw_readl((p)->membase + KS8695_URMS)
#define UART_GET_LSR(p)		__raw_readl((p)->membase + KS8695_URLS)
#define UART_GET_LCR(p)		__raw_readl((p)->membase + KS8695_URLC)
#define UART_PUT_LCR(p, c)	__raw_writel((c), (p)->membase + KS8695_URLC)
#define UART_GET_MCR(p)		__raw_readl((p)->membase + KS8695_URMC)
#define UART_PUT_MCR(p, c)	__raw_writel((c), (p)->membase + KS8695_URMC)
#define UART_GET_BRDR(p)	__raw_readl((p)->membase + KS8695_URBD)
#define UART_PUT_BRDR(p, c)	__raw_writel((c), (p)->membase + KS8695_URBD)

#define KS8695_CLR_TX_INT()	__raw_writel(1 << KS8695_IRQ_UART_TX, KS8695_IRQ_VA + KS8695_INTST)

#define UART_DUMMY_LSR_RX	0x100
#define UART_PORT_SIZE		(KS8695_USR - KS8695_URRB + 4)

static inline int tx_enabled(struct uart_port *port)
{
	return port->unused[0] & 1;
}

static inline int rx_enabled(struct uart_port *port)
{
	return port->unused[0] & 2;
}

static inline int ms_enabled(struct uart_port *port)
{
	return port->unused[0] & 4;
}

static inline void ms_enable(struct uart_port *port, int enabled)
{
	if(enabled)
		port->unused[0] |= 4;
	else
		port->unused[0] &= ~4;
}

static inline void rx_enable(struct uart_port *port, int enabled)
{
	if(enabled)
		port->unused[0] |= 2;
	else
		port->unused[0] &= ~2;
}

static inline void tx_enable(struct uart_port *port, int enabled)
{
	if(enabled)
		port->unused[0] |= 1;
	else
		port->unused[0] &= ~1;
}


#ifdef SUPPORT_SYSRQ
static struct console ks8695_console;
#endif

static void ks8695uart_stop_tx(struct uart_port *port)
{
	if (tx_enabled(port)) {
		/* use disable_irq_nosync() and not disable_irq() to avoid self
		 * imposed deadlock by not waiting for irq handler to end,
		 * since this ks8695uart_stop_tx() is called from interrupt context.
		 */
		disable_irq_nosync(KS8695_IRQ_UART_TX);
		tx_enable(port, 0);
	}
}

static void ks8695uart_start_tx(struct uart_port *port)
{
	if (!tx_enabled(port)) {
		enable_irq(KS8695_IRQ_UART_TX);
		tx_enable(port, 1);
	}
}

static void ks8695uart_stop_rx(struct uart_port *port)
{
	if (rx_enabled(port)) {
		disable_irq(KS8695_IRQ_UART_RX);
		rx_enable(port, 0);
	}
}

static void ks8695uart_enable_ms(struct uart_port *port)
{
	if (!ms_enabled(port)) {
		enable_irq(KS8695_IRQ_UART_MODEM_STATUS);
		ms_enable(port,1);
	}
}

static void ks8695uart_disable_ms(struct uart_port *port)
{
	if (ms_enabled(port)) {
		disable_irq(KS8695_IRQ_UART_MODEM_STATUS);
		ms_enable(port,0);
	}
}

static irqreturn_t ks8695uart_rx_chars(int irq, void *dev_id)
{
	struct uart_port *port = dev_id;
	unsigned int status, ch, lsr, flg, max_count = 256;

	status = UART_GET_LSR(port);		/* clears pending LSR interrupts */
	while ((status & URLS_URDR) && max_count--) {
		ch = UART_GET_CHAR(port);
		flg = TTY_NORMAL;

		port->icount.rx++;

		/*
		 * Note that the error handling code is
		 * out of the main execution path
		 */
		lsr = UART_GET_LSR(port) | UART_DUMMY_LSR_RX;
		if (unlikely(lsr & (URLS_URBI | URLS_URPE | URLS_URFE | URLS_URROE))) {
			if (lsr & URLS_URBI) {
				lsr &= ~(URLS_URFE | URLS_URPE);
				port->icount.brk++;
				if (uart_handle_break(port))
					goto ignore_char;
			}
			if (lsr & URLS_URPE)
				port->icount.parity++;
			if (lsr & URLS_URFE)
				port->icount.frame++;
			if (lsr & URLS_URROE)
				port->icount.overrun++;

			lsr &= port->read_status_mask;

			if (lsr & URLS_URBI)
				flg = TTY_BREAK;
			else if (lsr & URLS_URPE)
				flg = TTY_PARITY;
			else if (lsr & URLS_URFE)
				flg = TTY_FRAME;
		}

		if (uart_handle_sysrq_char(port, ch))
			goto ignore_char;

		uart_insert_char(port, lsr, URLS_URROE, ch, flg);

ignore_char:
		status = UART_GET_LSR(port);
	}
	tty_flip_buffer_push(&port->state->port);

	return IRQ_HANDLED;
}


static irqreturn_t ks8695uart_tx_chars(int irq, void *dev_id)
{
	struct uart_port *port = dev_id;
	struct circ_buf *xmit = &port->state->xmit;
	unsigned int count;

	if (port->x_char) {
		KS8695_CLR_TX_INT();
		UART_PUT_CHAR(port, port->x_char);
		port->icount.tx++;
		port->x_char = 0;
		return IRQ_HANDLED;
	}

	if (uart_tx_stopped(port) || uart_circ_empty(xmit)) {
		ks8695uart_stop_tx(port);
		return IRQ_HANDLED;
	}

	count = 16;	/* fifo size */
	while (!uart_circ_empty(xmit) && (count-- > 0)) {
		KS8695_CLR_TX_INT();
		UART_PUT_CHAR(port, xmit->buf[xmit->tail]);

		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
		port->icount.tx++;
	}

	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
		uart_write_wakeup(port);

	if (uart_circ_empty(xmit))
		ks8695uart_stop_tx(port);

	return IRQ_HANDLED;
}

static irqreturn_t ks8695uart_modem_status(int irq, void *dev_id)
{
	struct uart_port *port = dev_id;
	unsigned int status;

	/*
	 * clear modem interrupt by reading MSR
	 */
	status = UART_GET_MSR(port);

	if (status & URMS_URDDCD)
		uart_handle_dcd_change(port, status & URMS_URDDCD);

	if (status & URMS_URDDST)
		port->icount.dsr++;

	if (status & URMS_URDCTS)
		uart_handle_cts_change(port, status & URMS_URDCTS);

	if (status & URMS_URTERI)
		port->icount.rng++;

	wake_up_interruptible(&port->state->port.delta_msr_wait);

	return IRQ_HANDLED;
}

static unsigned int ks8695uart_tx_empty(struct uart_port *port)
{
	return (UART_GET_LSR(port) & URLS_URTE) ? TIOCSER_TEMT : 0;
}

static unsigned int ks8695uart_get_mctrl(struct uart_port *port)
{
	unsigned int result = 0;
	unsigned int status;

	status = UART_GET_MSR(port);
	if (status & URMS_URDCD)
		result |= TIOCM_CAR;
	if (status & URMS_URDSR)
		result |= TIOCM_DSR;
	if (status & URMS_URCTS)
		result |= TIOCM_CTS;
	if (status & URMS_URRI)
		result |= TIOCM_RI;

	return result;
}

static void ks8695uart_set_mctrl(struct uart_port *port, u_int mctrl)
{
	unsigned int mcr;

	mcr = UART_GET_MCR(port);
	if (mctrl & TIOCM_RTS)
		mcr |= URMC_URRTS;
	else
		mcr &= ~URMC_URRTS;

	if (mctrl & TIOCM_DTR)
		mcr |= URMC_URDTR;
	else
		mcr &= ~URMC_URDTR;

	UART_PUT_MCR(port, mcr);
}

static void ks8695uart_break_ctl(struct uart_port *port, int break_state)
{
	unsigned int lcr;

	lcr = UART_GET_LCR(port);

	if (break_state == -1)
		lcr |= URLC_URSBC;
	else
		lcr &= ~URLC_URSBC;

	UART_PUT_LCR(port, lcr);
}

static int ks8695uart_startup(struct uart_port *port)
{
	int retval;

	set_irq_flags(KS8695_IRQ_UART_TX, IRQF_VALID | IRQF_NOAUTOEN);
	tx_enable(port, 0);
	rx_enable(port, 1);
	ms_enable(port, 1);

	/*
	 * Allocate the IRQ
	 */
	retval = request_irq(KS8695_IRQ_UART_TX, ks8695uart_tx_chars, 0, "UART TX", port);
	if (retval)
		goto err_tx;

	retval = request_irq(KS8695_IRQ_UART_RX, ks8695uart_rx_chars, 0, "UART RX", port);
	if (retval)
		goto err_rx;

	retval = request_irq(KS8695_IRQ_UART_LINE_STATUS, ks8695uart_rx_chars, 0, "UART LineStatus", port);
	if (retval)
		goto err_ls;

	retval = request_irq(KS8695_IRQ_UART_MODEM_STATUS, ks8695uart_modem_status, 0, "UART ModemStatus", port);
	if (retval)
		goto err_ms;

	return 0;

err_ms:
	free_irq(KS8695_IRQ_UART_LINE_STATUS, port);
err_ls:
	free_irq(KS8695_IRQ_UART_RX, port);
err_rx:
	free_irq(KS8695_IRQ_UART_TX, port);
err_tx:
	return retval;
}

static void ks8695uart_shutdown(struct uart_port *port)
{
	/*
	 * Free the interrupt
	 */
	free_irq(KS8695_IRQ_UART_RX, port);
	free_irq(KS8695_IRQ_UART_TX, port);
	free_irq(KS8695_IRQ_UART_MODEM_STATUS, port);
	free_irq(KS8695_IRQ_UART_LINE_STATUS, port);

	/* disable break condition and fifos */
	UART_PUT_LCR(port, UART_GET_LCR(port) & ~URLC_URSBC);
	UART_PUT_FCR(port, UART_GET_FCR(port) & ~URFC_URFE);
}

static void ks8695uart_set_termios(struct uart_port *port, struct ktermios *termios, struct ktermios *old)
{
	unsigned int lcr, fcr = 0;
	unsigned long flags;
	unsigned int baud, quot;

	/*
	 * Ask the core to calculate the divisor for us.
	 */
	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
	quot = uart_get_divisor(port, baud);

	switch (termios->c_cflag & CSIZE) {
	case CS5:
		lcr = URCL_5;
		break;
	case CS6:
		lcr = URCL_6;
		break;
	case CS7:
		lcr = URCL_7;
		break;
	default:
		lcr = URCL_8;
		break;
	}

	/* stop bits */
	if (termios->c_cflag & CSTOPB)
		lcr |= URLC_URSB;

	/* parity */
	if (termios->c_cflag & PARENB) {
		if (termios->c_cflag & CMSPAR) {	/* Mark or Space parity */
			if (termios->c_cflag & PARODD)
				lcr |= URPE_MARK;
			else
				lcr |= URPE_SPACE;
		}
		else if (termios->c_cflag & PARODD)
			lcr |= URPE_ODD;
		else
			lcr |= URPE_EVEN;
	}

	if (port->fifosize > 1)
		fcr = URFC_URFRT_8 | URFC_URTFR | URFC_URRFR | URFC_URFE;

	spin_lock_irqsave(&port->lock, flags);

	/*
	 * Update the per-port timeout.
	 */
	uart_update_timeout(port, termios->c_cflag, baud);

	port->read_status_mask = URLS_URROE;
	if (termios->c_iflag & INPCK)
		port->read_status_mask |= (URLS_URFE | URLS_URPE);
	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
		port->read_status_mask |= URLS_URBI;

	/*
	 * Characters to ignore
	 */
	port->ignore_status_mask = 0;
	if (termios->c_iflag & IGNPAR)
		port->ignore_status_mask |= (URLS_URFE | URLS_URPE);
	if (termios->c_iflag & IGNBRK) {
		port->ignore_status_mask |= URLS_URBI;
		/*
		 * If we're ignoring parity and break indicators,
		 * ignore overruns too (for real raw support).
		 */
		if (termios->c_iflag & IGNPAR)
			port->ignore_status_mask |= URLS_URROE;
	}

	/*
	 * Ignore all characters if CREAD is not set.
	 */
	if ((termios->c_cflag & CREAD) == 0)
		port->ignore_status_mask |= UART_DUMMY_LSR_RX;

	/* first, disable everything */
	if (UART_ENABLE_MS(port, termios->c_cflag))
		ks8695uart_enable_ms(port);
	else
		ks8695uart_disable_ms(port);

	/* Set baud rate */
	UART_PUT_BRDR(port, quot);

	UART_PUT_LCR(port, lcr);
	UART_PUT_FCR(port, fcr);

	spin_unlock_irqrestore(&port->lock, flags);
}

static const char *ks8695uart_type(struct uart_port *port)
{
	return port->type == PORT_KS8695 ? "KS8695" : NULL;
}

/*
 * Release the memory region(s) being used by 'port'
 */
static void ks8695uart_release_port(struct uart_port *port)
{
	release_mem_region(port->mapbase, UART_PORT_SIZE);
}

/*
 * Request the memory region(s) being used by 'port'
 */
static int ks8695uart_request_port(struct uart_port *port)
{
	return request_mem_region(port->mapbase, UART_PORT_SIZE,
			"serial_ks8695") != NULL ? 0 : -EBUSY;
}

/*
 * Configure/autoconfigure the port.
 */
static void ks8695uart_config_port(struct uart_port *port, int flags)
{
	if (flags & UART_CONFIG_TYPE) {
		port->type = PORT_KS8695;
		ks8695uart_request_port(port);
	}
}

/*
 * verify the new serial_struct (for TIOCSSERIAL).
 */
static int ks8695uart_verify_port(struct uart_port *port, struct serial_struct *ser)
{
	int ret = 0;

	if (ser->type != PORT_UNKNOWN && ser->type != PORT_KS8695)
		ret = -EINVAL;
	if (ser->irq != port->irq)
		ret = -EINVAL;
	if (ser->baud_base < 9600)
		ret = -EINVAL;
	return ret;
}

static struct uart_ops ks8695uart_pops = {
	.tx_empty	= ks8695uart_tx_empty,
	.set_mctrl	= ks8695uart_set_mctrl,
	.get_mctrl	= ks8695uart_get_mctrl,
	.stop_tx	= ks8695uart_stop_tx,
	.start_tx	= ks8695uart_start_tx,
	.stop_rx	= ks8695uart_stop_rx,
	.enable_ms	= ks8695uart_enable_ms,
	.break_ctl	= ks8695uart_break_ctl,
	.startup	= ks8695uart_startup,
	.shutdown	= ks8695uart_shutdown,
	.set_termios	= ks8695uart_set_termios,
	.type		= ks8695uart_type,
	.release_port	= ks8695uart_release_port,
	.request_port	= ks8695uart_request_port,
	.config_port	= ks8695uart_config_port,
	.verify_port	= ks8695uart_verify_port,
};

static struct uart_port ks8695uart_ports[SERIAL_KS8695_NR] = {
	{
		.membase	= KS8695_UART_VA,
		.mapbase	= KS8695_UART_PA,
		.iotype		= SERIAL_IO_MEM,
		.irq		= KS8695_IRQ_UART_TX,
		.uartclk	= KS8695_CLOCK_RATE * 16,
		.fifosize	= 16,
		.ops		= &ks8695uart_pops,
		.flags		= ASYNC_BOOT_AUTOCONF,
		.line		= 0,
	}
};

#ifdef CONFIG_SERIAL_KS8695_CONSOLE
static void ks8695_console_putchar(struct uart_port *port, int ch)
{
	while (!(UART_GET_LSR(port) & URLS_URTHRE))
		barrier();

	UART_PUT_CHAR(port, ch);
}

static void ks8695_console_write(struct console *co, const char *s, u_int count)
{
	struct uart_port *port = ks8695uart_ports + co->index;

	uart_console_write(port, s, count, ks8695_console_putchar);
}

static void __init ks8695_console_get_options(struct uart_port *port, int *baud, int *parity, int *bits)
{
	unsigned int lcr;

	lcr = UART_GET_LCR(port);

	switch (lcr & URLC_PARITY) {
		case URPE_ODD:
			*parity = 'o';
			break;
		case URPE_EVEN:
			*parity = 'e';
			break;
		default:
			*parity = 'n';
	}

	switch (lcr & URLC_URCL) {
		case URCL_5:
			*bits = 5;
			break;
		case URCL_6:
			*bits = 6;
			break;
		case URCL_7:
			*bits = 7;
			break;
		default:
			*bits = 8;
	}

	*baud = port->uartclk / (UART_GET_BRDR(port) & 0x0FFF);
	*baud /= 16;
	*baud &= 0xFFFFFFF0;
}

static int __init ks8695_console_setup(struct console *co, char *options)
{
	struct uart_port *port;
	int baud = 115200;
	int bits = 8;
	int parity = 'n';
	int flow = 'n';

	/*
	 * Check whether an invalid uart number has been specified, and
	 * if so, search for the first available port that does have
	 * console support.
	 */
	port = uart_get_console(ks8695uart_ports, SERIAL_KS8695_NR, co);

	if (options)
		uart_parse_options(options, &baud, &parity, &bits, &flow);
	else
		ks8695_console_get_options(port, &baud, &parity, &bits);

	return uart_set_options(port, co, baud, parity, bits, flow);
}

static struct uart_driver ks8695_reg;

static struct console ks8695_console = {
	.name		= SERIAL_KS8695_DEVNAME,
	.write		= ks8695_console_write,
	.device		= uart_console_device,
	.setup		= ks8695_console_setup,
	.flags		= CON_PRINTBUFFER,
	.index		= -1,
	.data		= &ks8695_reg,
};

static int __init ks8695_console_init(void)
{
	add_preferred_console(SERIAL_KS8695_DEVNAME, 0, NULL);
	register_console(&ks8695_console);
	return 0;
}

console_initcall(ks8695_console_init);

#define KS8695_CONSOLE	&ks8695_console
#else
#define KS8695_CONSOLE	NULL
#endif

static struct uart_driver ks8695_reg = {
	.owner			= THIS_MODULE,
	.driver_name		= "serial_ks8695",
	.dev_name		= SERIAL_KS8695_DEVNAME,
	.major			= SERIAL_KS8695_MAJOR,
	.minor			= SERIAL_KS8695_MINOR,
	.nr			= SERIAL_KS8695_NR,
	.cons			= KS8695_CONSOLE,
};

static int __init ks8695uart_init(void)
{
	int i, ret;

	printk(KERN_INFO "Serial: Micrel KS8695 UART driver\n");

	ret = uart_register_driver(&ks8695_reg);
	if (ret)
		return ret;

	for (i = 0; i < SERIAL_KS8695_NR; i++)
		uart_add_one_port(&ks8695_reg, &ks8695uart_ports[0]);

	return 0;
}

static void __exit ks8695uart_exit(void)
{
	int i;

	for (i = 0; i < SERIAL_KS8695_NR; i++)
		uart_remove_one_port(&ks8695_reg, &ks8695uart_ports[0]);
	uart_unregister_driver(&ks8695_reg);
}

module_init(ks8695uart_init);
module_exit(ks8695uart_exit);

MODULE_DESCRIPTION("KS8695 serial port driver");
MODULE_AUTHOR("Micrel Inc.");
MODULE_LICENSE("GPL");
Commit	Line	Data
2c7ee6ab	1	/*
2c7ee6ab AV	2	* Driver for KS8695 serial ports
	3	*
	4	* Based on drivers/serial/serial_amba.c, by Kam Lee.
	5	*
	6	* Copyright 2002-2005 Micrel Inc.
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	*/
	14	#include <linux/module.h>
	15	#include <linux/tty.h>
ee160a38	16	#include <linux/tty_flip.h>
2c7ee6ab AV	17	#include <linux/ioport.h>
	18	#include <linux/init.h>
	19	#include <linux/serial.h>
	20	#include <linux/console.h>
	21	#include <linux/sysrq.h>
	22	#include <linux/device.h>
	23
	24	#include <asm/io.h>
	25	#include <asm/irq.h>
	26	#include <asm/mach/irq.h>
	27
a09e64fb RK	28	#include <mach/regs-uart.h>
a09e64fb RK	29	#include <mach/regs-irq.h>
2c7ee6ab AV	30
	31	#if defined(CONFIG_SERIAL_KS8695_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
	32	#define SUPPORT_SYSRQ
	33	#endif
	34
	35	#include <linux/serial_core.h>
	36
	37
	38	#define SERIAL_KS8695_MAJOR 204
	39	#define SERIAL_KS8695_MINOR 16
	40	#define SERIAL_KS8695_DEVNAME "ttyAM"
	41
	42	#define SERIAL_KS8695_NR 1
	43
	44	/*
	45	* Access macros for the KS8695 UART
	46	*/
	47	#define UART_GET_CHAR(p) (__raw_readl((p)->membase + KS8695_URRB) & 0xFF)
	48	#define UART_PUT_CHAR(p, c) __raw_writel((c), (p)->membase + KS8695_URTH)
	49	#define UART_GET_FCR(p) __raw_readl((p)->membase + KS8695_URFC)
	50	#define UART_PUT_FCR(p, c) __raw_writel((c), (p)->membase + KS8695_URFC)
	51	#define UART_GET_MSR(p) __raw_readl((p)->membase + KS8695_URMS)
	52	#define UART_GET_LSR(p) __raw_readl((p)->membase + KS8695_URLS)
	53	#define UART_GET_LCR(p) __raw_readl((p)->membase + KS8695_URLC)
	54	#define UART_PUT_LCR(p, c) __raw_writel((c), (p)->membase + KS8695_URLC)
	55	#define UART_GET_MCR(p) __raw_readl((p)->membase + KS8695_URMC)
	56	#define UART_PUT_MCR(p, c) __raw_writel((c), (p)->membase + KS8695_URMC)
	57	#define UART_GET_BRDR(p) __raw_readl((p)->membase + KS8695_URBD)
	58	#define UART_PUT_BRDR(p, c) __raw_writel((c), (p)->membase + KS8695_URBD)
	59
	60	#define KS8695_CLR_TX_INT() __raw_writel(1 << KS8695_IRQ_UART_TX, KS8695_IRQ_VA + KS8695_INTST)
	61
	62	#define UART_DUMMY_LSR_RX 0x100
	63	#define UART_PORT_SIZE (KS8695_USR - KS8695_URRB + 4)
	64
457cd4f5 DH	65	static inline int tx_enabled(struct uart_port *port)
	66	{
	67	return port->unused[0] & 1;
	68	}
	69
	70	static inline int rx_enabled(struct uart_port *port)
	71	{
	72	return port->unused[0] & 2;
	73	}
	74
	75	static inline int ms_enabled(struct uart_port *port)
	76	{
	77	return port->unused[0] & 4;
	78	}
	79
	80	static inline void ms_enable(struct uart_port *port, int enabled)
	81	{
	82	if(enabled)
	83	port->unused[0] \|= 4;
	84	else
	85	port->unused[0] &= ~4;
	86	}
	87
	88	static inline void rx_enable(struct uart_port *port, int enabled)
	89	{
	90	if(enabled)
	91	port->unused[0] \|= 2;
	92	else
	93	port->unused[0] &= ~2;
	94	}
	95
	96	static inline void tx_enable(struct uart_port *port, int enabled)
	97	{
	98	if(enabled)
	99	port->unused[0] \|= 1;
	100	else
	101	port->unused[0] &= ~1;
	102	}
2c7ee6ab AV	103
	104
	105	#ifdef SUPPORT_SYSRQ
	106	static struct console ks8695_console;
	107	#endif
	108
	109	static void ks8695uart_stop_tx(struct uart_port *port)
	110	{
	111	if (tx_enabled(port)) {
c47a830c DH	112	/* use disable_irq_nosync() and not disable_irq() to avoid self
	113	* imposed deadlock by not waiting for irq handler to end,
	114	* since this ks8695uart_stop_tx() is called from interrupt context.
	115	*/
	116	disable_irq_nosync(KS8695_IRQ_UART_TX);
457cd4f5	117	tx_enable(port, 0);
2c7ee6ab AV	118	}
	119	}
	120
	121	static void ks8695uart_start_tx(struct uart_port *port)
	122	{
	123	if (!tx_enabled(port)) {
	124	enable_irq(KS8695_IRQ_UART_TX);
457cd4f5	125	tx_enable(port, 1);
2c7ee6ab AV	126	}
	127	}
	128
	129	static void ks8695uart_stop_rx(struct uart_port *port)
	130	{
	131	if (rx_enabled(port)) {
	132	disable_irq(KS8695_IRQ_UART_RX);
457cd4f5	133	rx_enable(port, 0);
2c7ee6ab AV	134	}
	135	}
	136
	137	static void ks8695uart_enable_ms(struct uart_port *port)
	138	{
457cd4f5 DH	139	if (!ms_enabled(port)) {
	140	enable_irq(KS8695_IRQ_UART_MODEM_STATUS);
	141	ms_enable(port,1);
	142	}
2c7ee6ab AV	143	}
	144
	145	static void ks8695uart_disable_ms(struct uart_port *port)
	146	{
457cd4f5 DH	147	if (ms_enabled(port)) {
	148	disable_irq(KS8695_IRQ_UART_MODEM_STATUS);
	149	ms_enable(port,0);
	150	}
2c7ee6ab AV	151	}
	152
	153	static irqreturn_t ks8695uart_rx_chars(int irq, void *dev_id)
	154	{
	155	struct uart_port *port = dev_id;
2c7ee6ab AV	156	unsigned int status, ch, lsr, flg, max_count = 256;
	157
	158	status = UART_GET_LSR(port); /* clears pending LSR interrupts */
	159	while ((status & URLS_URDR) && max_count--) {
	160	ch = UART_GET_CHAR(port);
	161	flg = TTY_NORMAL;
	162
	163	port->icount.rx++;
	164
	165	/*
	166	* Note that the error handling code is
	167	* out of the main execution path
	168	*/
	169	lsr = UART_GET_LSR(port) \| UART_DUMMY_LSR_RX;
	170	if (unlikely(lsr & (URLS_URBI \| URLS_URPE \| URLS_URFE \| URLS_URROE))) {
	171	if (lsr & URLS_URBI) {
	172	lsr &= ~(URLS_URFE \| URLS_URPE);
	173	port->icount.brk++;
	174	if (uart_handle_break(port))
	175	goto ignore_char;
	176	}
	177	if (lsr & URLS_URPE)
	178	port->icount.parity++;
	179	if (lsr & URLS_URFE)
	180	port->icount.frame++;
	181	if (lsr & URLS_URROE)
	182	port->icount.overrun++;
	183
	184	lsr &= port->read_status_mask;
	185
	186	if (lsr & URLS_URBI)
	187	flg = TTY_BREAK;
	188	else if (lsr & URLS_URPE)
	189	flg = TTY_PARITY;
	190	else if (lsr & URLS_URFE)
	191	flg = TTY_FRAME;
	192	}
	193
	194	if (uart_handle_sysrq_char(port, ch))
	195	goto ignore_char;
	196
	197	uart_insert_char(port, lsr, URLS_URROE, ch, flg);
	198
	199	ignore_char:
	200	status = UART_GET_LSR(port);
	201	}
2e124b4a	202	tty_flip_buffer_push(&port->state->port);
2c7ee6ab AV	203
	204	return IRQ_HANDLED;
	205	}
	206
	207
	208	static irqreturn_t ks8695uart_tx_chars(int irq, void *dev_id)
	209	{
	210	struct uart_port *port = dev_id;
ebd2c8f6	211	struct circ_buf *xmit = &port->state->xmit;
2c7ee6ab AV	212	unsigned int count;
	213
	214	if (port->x_char) {
	215	KS8695_CLR_TX_INT();
	216	UART_PUT_CHAR(port, port->x_char);
	217	port->icount.tx++;
	218	port->x_char = 0;
	219	return IRQ_HANDLED;
	220	}
	221
	222	if (uart_tx_stopped(port) \|\| uart_circ_empty(xmit)) {
	223	ks8695uart_stop_tx(port);
	224	return IRQ_HANDLED;
	225	}
	226
	227	count = 16; /* fifo size */
	228	while (!uart_circ_empty(xmit) && (count-- > 0)) {
	229	KS8695_CLR_TX_INT();
	230	UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
	231
	232	xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
	233	port->icount.tx++;
	234	}
	235
	236	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
	237	uart_write_wakeup(port);
	238
	239	if (uart_circ_empty(xmit))
	240	ks8695uart_stop_tx(port);
	241
	242	return IRQ_HANDLED;
	243	}
	244
	245	static irqreturn_t ks8695uart_modem_status(int irq, void *dev_id)
	246	{
	247	struct uart_port *port = dev_id;
	248	unsigned int status;
	249
	250	/*
	251	* clear modem interrupt by reading MSR
	252	*/
	253	status = UART_GET_MSR(port);
	254
	255	if (status & URMS_URDDCD)
	256	uart_handle_dcd_change(port, status & URMS_URDDCD);
	257
	258	if (status & URMS_URDDST)
	259	port->icount.dsr++;
	260
	261	if (status & URMS_URDCTS)
	262	uart_handle_cts_change(port, status & URMS_URDCTS);
	263
	264	if (status & URMS_URTERI)
	265	port->icount.rng++;
	266
bdc04e31	267	wake_up_interruptible(&port->state->port.delta_msr_wait);
2c7ee6ab AV	268
	269	return IRQ_HANDLED;
	270	}
	271
	272	static unsigned int ks8695uart_tx_empty(struct uart_port *port)
	273	{
	274	return (UART_GET_LSR(port) & URLS_URTE) ? TIOCSER_TEMT : 0;
	275	}
	276
	277	static unsigned int ks8695uart_get_mctrl(struct uart_port *port)
	278	{
	279	unsigned int result = 0;
	280	unsigned int status;
	281
	282	status = UART_GET_MSR(port);
	283	if (status & URMS_URDCD)
	284	result \|= TIOCM_CAR;
	285	if (status & URMS_URDSR)
	286	result \|= TIOCM_DSR;
	287	if (status & URMS_URCTS)
	288	result \|= TIOCM_CTS;
	289	if (status & URMS_URRI)
	290	result \|= TIOCM_RI;
	291
	292	return result;
	293	}
	294
	295	static void ks8695uart_set_mctrl(struct uart_port *port, u_int mctrl)
	296	{
	297	unsigned int mcr;
	298
	299	mcr = UART_GET_MCR(port);
	300	if (mctrl & TIOCM_RTS)
	301	mcr \|= URMC_URRTS;
	302	else
	303	mcr &= ~URMC_URRTS;
	304
	305	if (mctrl & TIOCM_DTR)
	306	mcr \|= URMC_URDTR;
	307	else
	308	mcr &= ~URMC_URDTR;
	309
	310	UART_PUT_MCR(port, mcr);
	311	}
	312
	313	static void ks8695uart_break_ctl(struct uart_port *port, int break_state)
	314	{
	315	unsigned int lcr;
	316
	317	lcr = UART_GET_LCR(port);
	318
	319	if (break_state == -1)
	320	lcr \|= URLC_URSBC;
	321	else
	322	lcr &= ~URLC_URSBC;
	323
	324	UART_PUT_LCR(port, lcr);
	325	}
	326
	327	static int ks8695uart_startup(struct uart_port *port)
	328	{
	329	int retval;
	330
	331	set_irq_flags(KS8695_IRQ_UART_TX, IRQF_VALID \| IRQF_NOAUTOEN);
457cd4f5 DH	332	tx_enable(port, 0);
	333	rx_enable(port, 1);
	334	ms_enable(port, 1);
2c7ee6ab AV	335
	336	/*
	337	* Allocate the IRQ
	338	*/
9cfb5c05	339	retval = request_irq(KS8695_IRQ_UART_TX, ks8695uart_tx_chars, 0, "UART TX", port);
2c7ee6ab AV	340	if (retval)
	341	goto err_tx;
	342
9cfb5c05	343	retval = request_irq(KS8695_IRQ_UART_RX, ks8695uart_rx_chars, 0, "UART RX", port);
2c7ee6ab AV	344	if (retval)
	345	goto err_rx;
	346
9cfb5c05	347	retval = request_irq(KS8695_IRQ_UART_LINE_STATUS, ks8695uart_rx_chars, 0, "UART LineStatus", port);
2c7ee6ab	348	if (retval)
e45c7a43	349	goto err_ls;
2c7ee6ab	350
9cfb5c05	351	retval = request_irq(KS8695_IRQ_UART_MODEM_STATUS, ks8695uart_modem_status, 0, "UART ModemStatus", port);
2c7ee6ab	352	if (retval)
e45c7a43	353	goto err_ms;
2c7ee6ab AV	354
	355	return 0;
	356
	357	err_ms:
	358	free_irq(KS8695_IRQ_UART_LINE_STATUS, port);
	359	err_ls:
	360	free_irq(KS8695_IRQ_UART_RX, port);
	361	err_rx:
	362	free_irq(KS8695_IRQ_UART_TX, port);
	363	err_tx:
	364	return retval;
	365	}
	366
	367	static void ks8695uart_shutdown(struct uart_port *port)
	368	{
	369	/*
	370	* Free the interrupt
	371	*/
	372	free_irq(KS8695_IRQ_UART_RX, port);
	373	free_irq(KS8695_IRQ_UART_TX, port);
	374	free_irq(KS8695_IRQ_UART_MODEM_STATUS, port);
	375	free_irq(KS8695_IRQ_UART_LINE_STATUS, port);
	376
	377	/* disable break condition and fifos */
	378	UART_PUT_LCR(port, UART_GET_LCR(port) & ~URLC_URSBC);
	379	UART_PUT_FCR(port, UART_GET_FCR(port) & ~URFC_URFE);
	380	}
	381
	382	static void ks8695uart_set_termios(struct uart_port port, struct ktermios termios, struct ktermios *old)
	383	{
	384	unsigned int lcr, fcr = 0;
	385	unsigned long flags;
	386	unsigned int baud, quot;
	387
	388	/*
	389	* Ask the core to calculate the divisor for us.
	390	*/
	391	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
	392	quot = uart_get_divisor(port, baud);
	393
	394	switch (termios->c_cflag & CSIZE) {
	395	case CS5:
	396	lcr = URCL_5;
	397	break;
	398	case CS6:
	399	lcr = URCL_6;
	400	break;
	401	case CS7:
	402	lcr = URCL_7;
	403	break;
	404	default:
	405	lcr = URCL_8;
	406	break;
	407	}
	408
	409	/* stop bits */
	410	if (termios->c_cflag & CSTOPB)
	411	lcr \|= URLC_URSB;
	412
	413	/* parity */
	414	if (termios->c_cflag & PARENB) {
	415	if (termios->c_cflag & CMSPAR) { /* Mark or Space parity */
	416	if (termios->c_cflag & PARODD)
	417	lcr \|= URPE_MARK;
418	else
419	lcr \|= URPE_SPACE;
420	}
421	else if (termios->c_cflag & PARODD)
422	lcr \|= URPE_ODD;
423	else
424	lcr \|= URPE_EVEN;
425	}
426
427	if (port->fifosize > 1)
428	fcr = URFC_URFRT_8 \| URFC_URTFR \| URFC_URRFR \| URFC_URFE;
429
430	spin_lock_irqsave(&port->lock, flags);
431
432	/*
433	* Update the per-port timeout.
434	*/
435	uart_update_timeout(port, termios->c_cflag, baud);
436
437	port->read_status_mask = URLS_URROE;
438	if (termios->c_iflag & INPCK)
439	port->read_status_mask \|= (URLS_URFE \| URLS_URPE);
ef8b9ddc	440	if (termios->c_iflag & (IGNBRK \| BRKINT \| PARMRK))
2c7ee6ab AV	441	port->read_status_mask \|= URLS_URBI;
	442
	443	/*
	444	* Characters to ignore
	445	*/
	446	port->ignore_status_mask = 0;
	447	if (termios->c_iflag & IGNPAR)
	448	port->ignore_status_mask \|= (URLS_URFE \| URLS_URPE);
	449	if (termios->c_iflag & IGNBRK) {
	450	port->ignore_status_mask \|= URLS_URBI;
	451	/*
	452	* If we're ignoring parity and break indicators,
	453	* ignore overruns too (for real raw support).
	454	*/
	455	if (termios->c_iflag & IGNPAR)
	456	port->ignore_status_mask \|= URLS_URROE;
	457	}
	458
	459	/*
	460	* Ignore all characters if CREAD is not set.
	461	*/
	462	if ((termios->c_cflag & CREAD) == 0)
	463	port->ignore_status_mask \|= UART_DUMMY_LSR_RX;
	464
	465	/* first, disable everything */
	466	if (UART_ENABLE_MS(port, termios->c_cflag))
	467	ks8695uart_enable_ms(port);
	468	else
	469	ks8695uart_disable_ms(port);
	470
	471	/* Set baud rate */
	472	UART_PUT_BRDR(port, quot);
	473
	474	UART_PUT_LCR(port, lcr);
	475	UART_PUT_FCR(port, fcr);
	476
	477	spin_unlock_irqrestore(&port->lock, flags);
	478	}
	479
	480	static const char ks8695uart_type(struct uart_port port)
	481	{
	482	return port->type == PORT_KS8695 ? "KS8695" : NULL;
	483	}
	484
	485	/*
	486	* Release the memory region(s) being used by 'port'
	487	*/
	488	static void ks8695uart_release_port(struct uart_port *port)
	489	{
	490	release_mem_region(port->mapbase, UART_PORT_SIZE);
	491	}
	492
	493	/*
	494	* Request the memory region(s) being used by 'port'
	495	*/
	496	static int ks8695uart_request_port(struct uart_port *port)
	497	{
	498	return request_mem_region(port->mapbase, UART_PORT_SIZE,
	499	"serial_ks8695") != NULL ? 0 : -EBUSY;
	500	}
	501
	502	/*
	503	* Configure/autoconfigure the port.
	504	*/
505	static void ks8695uart_config_port(struct uart_port *port, int flags)
506	{
507	if (flags & UART_CONFIG_TYPE) {
508	port->type = PORT_KS8695;
509	ks8695uart_request_port(port);
510	}
511	}
512
513	/*
514	* verify the new serial_struct (for TIOCSSERIAL).
515	*/
516	static int ks8695uart_verify_port(struct uart_port port, struct serial_struct ser)
517	{
518	int ret = 0;
519
520	if (ser->type != PORT_UNKNOWN && ser->type != PORT_KS8695)
521	ret = -EINVAL;
522	if (ser->irq != port->irq)
523	ret = -EINVAL;
524	if (ser->baud_base < 9600)
525	ret = -EINVAL;
526	return ret;
527	}
528
529	static struct uart_ops ks8695uart_pops = {
530	.tx_empty = ks8695uart_tx_empty,
531	.set_mctrl = ks8695uart_set_mctrl,
532	.get_mctrl = ks8695uart_get_mctrl,
533	.stop_tx = ks8695uart_stop_tx,
534	.start_tx = ks8695uart_start_tx,
535	.stop_rx = ks8695uart_stop_rx,
536	.enable_ms = ks8695uart_enable_ms,
537	.break_ctl = ks8695uart_break_ctl,
538	.startup = ks8695uart_startup,
539	.shutdown = ks8695uart_shutdown,
540	.set_termios = ks8695uart_set_termios,
541	.type = ks8695uart_type,
542	.release_port = ks8695uart_release_port,
543	.request_port = ks8695uart_request_port,
544	.config_port = ks8695uart_config_port,
545	.verify_port = ks8695uart_verify_port,
546	};
547
548	static struct uart_port ks8695uart_ports[SERIAL_KS8695_NR] = {
549	{
d19bd836 AB	550	.membase = KS8695_UART_VA,
d19bd836 AB	551	.mapbase = KS8695_UART_PA,
2c7ee6ab AV	552	.iotype = SERIAL_IO_MEM,
2c7ee6ab AV	553	.irq = KS8695_IRQ_UART_TX,
0a51810a	554	.uartclk = KS8695_CLOCK_RATE * 16,
2c7ee6ab AV	555	.fifosize = 16,
	556	.ops = &ks8695uart_pops,
	557	.flags = ASYNC_BOOT_AUTOCONF,
	558	.line = 0,
	559	}
	560	};
	561
	562	#ifdef CONFIG_SERIAL_KS8695_CONSOLE
	563	static void ks8695_console_putchar(struct uart_port *port, int ch)
	564	{
	565	while (!(UART_GET_LSR(port) & URLS_URTHRE))
	566	barrier();
	567
	568	UART_PUT_CHAR(port, ch);
	569	}
	570
	571	static void ks8695_console_write(struct console co, const char s, u_int count)
	572	{
	573	struct uart_port *port = ks8695uart_ports + co->index;
	574
	575	uart_console_write(port, s, count, ks8695_console_putchar);
	576	}
	577
	578	static void __init ks8695_console_get_options(struct uart_port port, int baud, int parity, int bits)
	579	{
	580	unsigned int lcr;
	581
	582	lcr = UART_GET_LCR(port);
	583
	584	switch (lcr & URLC_PARITY) {
	585	case URPE_ODD:
	586	*parity = 'o';
	587	break;
	588	case URPE_EVEN:
	589	*parity = 'e';
	590	break;
	591	default:
	592	*parity = 'n';
	593	}
	594
	595	switch (lcr & URLC_URCL) {
	596	case URCL_5:
	597	*bits = 5;
	598	break;
	599	case URCL_6:
	600	*bits = 6;
	601	break;
	602	case URCL_7:
	603	*bits = 7;
	604	break;
	605	default:
	606	*bits = 8;
	607	}
	608
	609	*baud = port->uartclk / (UART_GET_BRDR(port) & 0x0FFF);
	610	*baud /= 16;
	611	*baud &= 0xFFFFFFF0;
	612	}
	613
	614	static int __init ks8695_console_setup(struct console co, char options)
	615	{
	616	struct uart_port *port;
	617	int baud = 115200;
	618	int bits = 8;
619	int parity = 'n';
620	int flow = 'n';
621
622	/*
623	* Check whether an invalid uart number has been specified, and
624	* if so, search for the first available port that does have
625	* console support.
626	*/
627	port = uart_get_console(ks8695uart_ports, SERIAL_KS8695_NR, co);
628
629	if (options)
630	uart_parse_options(options, &baud, &parity, &bits, &flow);
631	else
632	ks8695_console_get_options(port, &baud, &parity, &bits);
633
634	return uart_set_options(port, co, baud, parity, bits, flow);
635	}
636
486cab2b	637	static struct uart_driver ks8695_reg;
2c7ee6ab AV	638
	639	static struct console ks8695_console = {
	640	.name = SERIAL_KS8695_DEVNAME,
	641	.write = ks8695_console_write,
	642	.device = uart_console_device,
	643	.setup = ks8695_console_setup,
	644	.flags = CON_PRINTBUFFER,
	645	.index = -1,
	646	.data = &ks8695_reg,
	647	};
	648
	649	static int __init ks8695_console_init(void)
	650	{
0ad70740	651	add_preferred_console(SERIAL_KS8695_DEVNAME, 0, NULL);
2c7ee6ab AV	652	register_console(&ks8695_console);
	653	return 0;
	654	}
	655
	656	console_initcall(ks8695_console_init);
	657
	658	#define KS8695_CONSOLE &ks8695_console
	659	#else
	660	#define KS8695_CONSOLE NULL
	661	#endif
	662
	663	static struct uart_driver ks8695_reg = {
	664	.owner = THIS_MODULE,
	665	.driver_name = "serial_ks8695",
	666	.dev_name = SERIAL_KS8695_DEVNAME,
	667	.major = SERIAL_KS8695_MAJOR,
	668	.minor = SERIAL_KS8695_MINOR,
	669	.nr = SERIAL_KS8695_NR,
	670	.cons = KS8695_CONSOLE,
	671	};
	672
	673	static int __init ks8695uart_init(void)
	674	{
	675	int i, ret;
	676
	677	printk(KERN_INFO "Serial: Micrel KS8695 UART driver\n");
	678
	679	ret = uart_register_driver(&ks8695_reg);
	680	if (ret)
	681	return ret;
	682
	683	for (i = 0; i < SERIAL_KS8695_NR; i++)
	684	uart_add_one_port(&ks8695_reg, &ks8695uart_ports[0]);
	685
	686	return 0;
	687	}
	688
	689	static void __exit ks8695uart_exit(void)
	690	{
	691	int i;
	692
	693	for (i = 0; i < SERIAL_KS8695_NR; i++)
	694	uart_remove_one_port(&ks8695_reg, &ks8695uart_ports[0]);
	695	uart_unregister_driver(&ks8695_reg);
	696	}
	697
	698	module_init(ks8695uart_init);
	699	module_exit(ks8695uart_exit);
	700
	701	MODULE_DESCRIPTION("KS8695 serial port driver");
	702	MODULE_AUTHOR("Micrel Inc.");
	703	MODULE_LICENSE("GPL");