Skip to content
Snippets Groups Projects
Select Git revision
  • b3e112bcc19abd8e9657dca34a87316786e096f3
  • vme-testing default
  • ci-test
  • master
  • remoteproc
  • am625-sk-ov5640
  • pcal6534-upstreaming
  • lps22df-upstreaming
  • msc-upstreaming
  • imx8mp
  • iio/noa1305
  • vme-next
  • vme-next-4.14-rc4
  • v4.14-rc4
  • v4.14-rc3
  • v4.14-rc2
  • v4.14-rc1
  • v4.13
  • vme-next-4.13-rc7
  • v4.13-rc7
  • v4.13-rc6
  • v4.13-rc5
  • v4.13-rc4
  • v4.13-rc3
  • v4.13-rc2
  • v4.13-rc1
  • v4.12
  • v4.12-rc7
  • v4.12-rc6
  • v4.12-rc5
  • v4.12-rc4
  • v4.12-rc3
32 results

m32r_sio.c

Blame
  • m32r_sio.c 27.67 KiB
    /*
     *  m32r_sio.c
     *
     *  Driver for M32R serial ports
     *
     *  Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
     *  Based on drivers/serial/8250.c.
     *
     *  Copyright (C) 2001  Russell King.
     *  Copyright (C) 2004  Hirokazu Takata <takata at linux-m32r.org>
     *
     * 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.
     */
    
    /*
     * A note about mapbase / membase
     *
     *  mapbase is the physical address of the IO port.  Currently, we don't
     *  support this very well, and it may well be dropped from this driver
     *  in future.  As such, mapbase should be NULL.
     *
     *  membase is an 'ioremapped' cookie.  This is compatible with the old
     *  serial.c driver, and is currently the preferred form.
     */
    #include <linux/config.h>
    
    #if defined(CONFIG_SERIAL_M32R_SIO_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
    #define SUPPORT_SYSRQ
    #endif
    
    #include <linux/module.h>
    #include <linux/tty.h>
    #include <linux/ioport.h>
    #include <linux/init.h>
    #include <linux/console.h>
    #include <linux/sysrq.h>
    #include <linux/serial.h>
    #include <linux/serialP.h>
    #include <linux/delay.h>
    
    #include <asm/m32r.h>
    #include <asm/io.h>
    #include <asm/irq.h>
    
    #define PORT_M32R_BASE	PORT_M32R_SIO
    #define PORT_INDEX(x)	(x - PORT_M32R_BASE + 1)
    #define BAUD_RATE	115200
    
    #include <linux/serial_core.h>
    #include "m32r_sio.h"
    #include "m32r_sio_reg.h"
    
    /*
     * Debugging.
     */
    #if 0
    #define DEBUG_AUTOCONF(fmt...)	printk(fmt)
    #else
    #define DEBUG_AUTOCONF(fmt...)	do { } while (0)
    #endif
    
    #if 0
    #define DEBUG_INTR(fmt...)	printk(fmt)
    #else
    #define DEBUG_INTR(fmt...)	do { } while (0)
    #endif
    
    #define PASS_LIMIT	256
    
    /*
     * We default to IRQ0 for the "no irq" hack.   Some
     * machine types want others as well - they're free
     * to redefine this in their header file.
     */
    #define is_real_interrupt(irq)	((irq) != 0)
    
    #include <asm/serial.h>
    
    /* Standard COM flags */
    #define STD_COM_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST)
    
    /*
     * SERIAL_PORT_DFNS tells us about built-in ports that have no
     * standard enumeration mechanism.   Platforms that can find all
     * serial ports via mechanisms like ACPI or PCI need not supply it.
     */
    #undef SERIAL_PORT_DFNS
    #if defined(CONFIG_PLAT_USRV)
    
    #define SERIAL_PORT_DFNS						\
           /* UART  CLK     PORT   IRQ            FLAGS */			\
    	{ 0, BASE_BAUD, 0x3F8, PLD_IRQ_UART0, STD_COM_FLAGS }, /* ttyS0 */ \
    	{ 0, BASE_BAUD, 0x2F8, PLD_IRQ_UART1, STD_COM_FLAGS }, /* ttyS1 */
    
    #else /* !CONFIG_PLAT_USRV */
    
    #if defined(CONFIG_SERIAL_M32R_PLDSIO)
    #define SERIAL_PORT_DFNS						\
    	{ 0, BASE_BAUD, ((unsigned long)PLD_ESIO0CR), PLD_IRQ_SIO0_RCV,	\
    	  STD_COM_FLAGS }, /* ttyS0 */
    #else
    #define SERIAL_PORT_DFNS						\
    	{ 0, BASE_BAUD, M32R_SIO_OFFSET, M32R_IRQ_SIO0_R,		\
    	  STD_COM_FLAGS }, /* ttyS0 */
    #endif
    
    #endif /* !CONFIG_PLAT_USRV */
    
    static struct old_serial_port old_serial_port[] = {
    	SERIAL_PORT_DFNS	/* defined in asm/serial.h */
    };
    
    #define UART_NR	ARRAY_SIZE(old_serial_port)
    
    struct uart_sio_port {
    	struct uart_port	port;
    	struct timer_list	timer;		/* "no irq" timer */
    	struct list_head	list;		/* ports on this IRQ */
    	unsigned short		rev;
    	unsigned char		acr;
    	unsigned char		ier;
    	unsigned char		lcr;
    	unsigned char		mcr_mask;	/* mask of user bits */
    	unsigned char		mcr_force;	/* mask of forced bits */
    	unsigned char		lsr_break_flag;
    
    	/*
    	 * We provide a per-port pm hook.
    	 */
    	void			(*pm)(struct uart_port *port,
    				      unsigned int state, unsigned int old);
    };
    
    struct irq_info {
    	spinlock_t		lock;
    	struct list_head	*head;
    };
    
    static struct irq_info irq_lists[NR_IRQS];
    
    /*
     * Here we define the default xmit fifo size used for each type of UART.
     */
    static const struct serial_uart_config uart_config[] = {
    	[PORT_UNKNOWN] = {
    		.name			= "unknown",
    		.dfl_xmit_fifo_size	= 1,
    		.flags			= 0,
    	},
    	[PORT_INDEX(PORT_M32R_SIO)] = {
    		.name			= "M32RSIO",
    		.dfl_xmit_fifo_size	= 1,
    		.flags			= 0,
    	},
    };
    
    #ifdef CONFIG_SERIAL_M32R_PLDSIO
    
    #define __sio_in(x) inw((unsigned long)(x))
    #define __sio_out(v,x) outw((v),(unsigned long)(x))
    
    static inline void sio_set_baud_rate(unsigned long baud)
    {
    	unsigned short sbaud;
    	sbaud = (boot_cpu_data.bus_clock / (baud * 4))-1;
    	__sio_out(sbaud, PLD_ESIO0BAUR);
    }
    
    static void sio_reset(void)
    {
    	unsigned short tmp;
    
    	tmp = __sio_in(PLD_ESIO0RXB);
    	tmp = __sio_in(PLD_ESIO0RXB);
    	tmp = __sio_in(PLD_ESIO0CR);
    	sio_set_baud_rate(BAUD_RATE);
    	__sio_out(0x0300, PLD_ESIO0CR);
    	__sio_out(0x0003, PLD_ESIO0CR);
    }
    
    static void sio_init(void)
    {
    	unsigned short tmp;
    
    	tmp = __sio_in(PLD_ESIO0RXB);
    	tmp = __sio_in(PLD_ESIO0RXB);
    	tmp = __sio_in(PLD_ESIO0CR);
    	__sio_out(0x0300, PLD_ESIO0CR);
    	__sio_out(0x0003, PLD_ESIO0CR);
    }
    
    static void sio_error(int *status)
    {
    	printk("SIO0 error[%04x]\n", *status);
    	do {
    		sio_init();
    	} while ((*status = __sio_in(PLD_ESIO0CR)) != 3);
    }
    
    #else /* not CONFIG_SERIAL_M32R_PLDSIO */
    
    #define __sio_in(x) inl(x)
    #define __sio_out(v,x) outl((v),(x))
    
    static inline void sio_set_baud_rate(unsigned long baud)
    {
    	unsigned long i, j;
    
    	i = boot_cpu_data.bus_clock / (baud * 16);
    	j = (boot_cpu_data.bus_clock - (i * baud * 16)) / baud;
    	i -= 1;
    	j = (j + 1) >> 1;
    
    	__sio_out(i, M32R_SIO0_BAUR_PORTL);
    	__sio_out(j, M32R_SIO0_RBAUR_PORTL);
    }
    
    static void sio_reset(void)
    {
    	__sio_out(0x00000300, M32R_SIO0_CR_PORTL);	/* init status */
    	__sio_out(0x00000800, M32R_SIO0_MOD1_PORTL);	/* 8bit        */
    	__sio_out(0x00000080, M32R_SIO0_MOD0_PORTL);	/* 1stop non   */
    	sio_set_baud_rate(BAUD_RATE);
    	__sio_out(0x00000000, M32R_SIO0_TRCR_PORTL);
    	__sio_out(0x00000003, M32R_SIO0_CR_PORTL);	/* RXCEN */
    }
    
    static void sio_init(void)
    {
    	unsigned int tmp;
    
    	tmp = __sio_in(M32R_SIO0_RXB_PORTL);
    	tmp = __sio_in(M32R_SIO0_RXB_PORTL);
    	tmp = __sio_in(M32R_SIO0_STS_PORTL);
    	__sio_out(0x00000003, M32R_SIO0_CR_PORTL);
    }
    
    static void sio_error(int *status)
    {
    	printk("SIO0 error[%04x]\n", *status);
    	do {
    		sio_init();
    	} while ((*status = __sio_in(M32R_SIO0_CR_PORTL)) != 3);
    }
    
    #endif /* CONFIG_SERIAL_M32R_PLDSIO */
    
    static _INLINE_ unsigned int sio_in(struct uart_sio_port *up, int offset)
    {
    	return __sio_in(up->port.iobase + offset);
    }
    
    static _INLINE_ void sio_out(struct uart_sio_port *up, int offset, int value)
    {
    	__sio_out(value, up->port.iobase + offset);
    }
    
    static _INLINE_ unsigned int serial_in(struct uart_sio_port *up, int offset)
    {
    	if (!offset)
    		return 0;
    
    	return __sio_in(offset);
    }
    
    static _INLINE_ void
    serial_out(struct uart_sio_port *up, int offset, int value)
    {
    	if (!offset)
    		return;
    
    	__sio_out(value, offset);
    }
    
    static void m32r_sio_stop_tx(struct uart_port *port, unsigned int tty_stop)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    
    	if (up->ier & UART_IER_THRI) {
    		up->ier &= ~UART_IER_THRI;
    		serial_out(up, UART_IER, up->ier);
    	}
    }
    
    static void m32r_sio_start_tx(struct uart_port *port, unsigned int tty_start)
    {
    #ifdef CONFIG_SERIAL_M32R_PLDSIO
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    	struct circ_buf *xmit = &up->port.info->xmit;
    
    	if (!(up->ier & UART_IER_THRI)) {
    		up->ier |= UART_IER_THRI;
    		serial_out(up, UART_IER, up->ier);
    		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
    		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
    		up->port.icount.tx++;
    	}
    	while((serial_in(up, UART_LSR) & UART_EMPTY) != UART_EMPTY);
    #else
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    
    	if (!(up->ier & UART_IER_THRI)) {
    		up->ier |= UART_IER_THRI;
    		serial_out(up, UART_IER, up->ier);
    	}
    #endif
    }
    
    static void m32r_sio_stop_rx(struct uart_port *port)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    
    	up->ier &= ~UART_IER_RLSI;
    	up->port.read_status_mask &= ~UART_LSR_DR;
    	serial_out(up, UART_IER, up->ier);
    }
    
    static void m32r_sio_enable_ms(struct uart_port *port)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    
    	up->ier |= UART_IER_MSI;
    	serial_out(up, UART_IER, up->ier);
    }
    
    static _INLINE_ void receive_chars(struct uart_sio_port *up, int *status,
    	struct pt_regs *regs)
    {
    	struct tty_struct *tty = up->port.info->tty;
    	unsigned char ch;
    	int max_count = 256;
    
    	do {
    		if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) {
    			tty->flip.work.func((void *)tty);
    			if (tty->flip.count >= TTY_FLIPBUF_SIZE)
    				return; // if TTY_DONT_FLIP is set
    		}
    		ch = sio_in(up, SIORXB);
    		*tty->flip.char_buf_ptr = ch;
    		*tty->flip.flag_buf_ptr = TTY_NORMAL;
    		up->port.icount.rx++;
    
    		if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
    				       UART_LSR_FE | UART_LSR_OE))) {
    			/*
    			 * For statistics only
    			 */
    			if (*status & UART_LSR_BI) {
    				*status &= ~(UART_LSR_FE | UART_LSR_PE);
    				up->port.icount.brk++;
    				/*
    				 * We do the SysRQ and SAK checking
    				 * here because otherwise the break
    				 * may get masked by ignore_status_mask
    				 * or read_status_mask.
    				 */
    				if (uart_handle_break(&up->port))
    					goto ignore_char;
    			} else if (*status & UART_LSR_PE)
    				up->port.icount.parity++;
    			else if (*status & UART_LSR_FE)
    				up->port.icount.frame++;
    			if (*status & UART_LSR_OE)
    				up->port.icount.overrun++;
    
    			/*
    			 * Mask off conditions which should be ingored.
    			 */
    			*status &= up->port.read_status_mask;
    
    			if (up->port.line == up->port.cons->index) {
    				/* Recover the break flag from console xmit */
    				*status |= up->lsr_break_flag;
    				up->lsr_break_flag = 0;
    			}
    
    			if (*status & UART_LSR_BI) {
    				DEBUG_INTR("handling break....");
    				*tty->flip.flag_buf_ptr = TTY_BREAK;
    			} else if (*status & UART_LSR_PE)
    				*tty->flip.flag_buf_ptr = TTY_PARITY;
    			else if (*status & UART_LSR_FE)
    				*tty->flip.flag_buf_ptr = TTY_FRAME;
    		}
    		if (uart_handle_sysrq_char(&up->port, ch, regs))
    			goto ignore_char;
    		if ((*status & up->port.ignore_status_mask) == 0) {
    			tty->flip.flag_buf_ptr++;
    			tty->flip.char_buf_ptr++;
    			tty->flip.count++;
    		}
    		if ((*status & UART_LSR_OE) &&
    		    tty->flip.count < TTY_FLIPBUF_SIZE) {
    			/*
    			 * Overrun is special, since it's reported
    			 * immediately, and doesn't affect the current
    			 * character.
    			 */
    			*tty->flip.flag_buf_ptr = TTY_OVERRUN;
    			tty->flip.flag_buf_ptr++;
    			tty->flip.char_buf_ptr++;
    			tty->flip.count++;
    		}
    	ignore_char:
    		*status = serial_in(up, UART_LSR);
    	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
    	tty_flip_buffer_push(tty);
    }
    
    static _INLINE_ void transmit_chars(struct uart_sio_port *up)
    {
    	struct circ_buf *xmit = &up->port.info->xmit;
    	int count;
    
    	if (up->port.x_char) {
    #ifndef CONFIG_SERIAL_M32R_PLDSIO	/* XXX */
    		serial_out(up, UART_TX, up->port.x_char);
    #endif
    		up->port.icount.tx++;
    		up->port.x_char = 0;
    		return;
    	}
    	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
    		m32r_sio_stop_tx(&up->port, 0);
    		return;
    	}
    
    	count = up->port.fifosize;
    	do {
    		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
    		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
    		up->port.icount.tx++;
    		if (uart_circ_empty(xmit))
    			break;
    		while (!serial_in(up, UART_LSR) & UART_LSR_THRE);
    
    	} while (--count > 0);
    
    	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
    		uart_write_wakeup(&up->port);
    
    	DEBUG_INTR("THRE...");
    
    	if (uart_circ_empty(xmit))
    		m32r_sio_stop_tx(&up->port, 0);
    }
    
    /*
     * This handles the interrupt from one port.
     */
    static inline void m32r_sio_handle_port(struct uart_sio_port *up,
    	unsigned int status, struct pt_regs *regs)
    {
    	DEBUG_INTR("status = %x...", status);
    
    	if (status & 0x04)
    		receive_chars(up, &status, regs);
    	if (status & 0x01)
    		transmit_chars(up);
    }
    
    /*
     * This is the serial driver's interrupt routine.
     *
     * Arjan thinks the old way was overly complex, so it got simplified.
     * Alan disagrees, saying that need the complexity to handle the weird
     * nature of ISA shared interrupts.  (This is a special exception.)
     *
     * In order to handle ISA shared interrupts properly, we need to check
     * that all ports have been serviced, and therefore the ISA interrupt
     * line has been de-asserted.
     *
     * This means we need to loop through all ports. checking that they
     * don't have an interrupt pending.
     */
    static irqreturn_t m32r_sio_interrupt(int irq, void *dev_id,
    	struct pt_regs *regs)
    {
    	struct irq_info *i = dev_id;
    	struct list_head *l, *end = NULL;
    	int pass_counter = 0;
    
    	DEBUG_INTR("m32r_sio_interrupt(%d)...", irq);
    
    #ifdef CONFIG_SERIAL_M32R_PLDSIO
    //	if (irq == PLD_IRQ_SIO0_SND)
    //		irq = PLD_IRQ_SIO0_RCV;
    #else
    	if (irq == M32R_IRQ_SIO0_S)
    		irq = M32R_IRQ_SIO0_R;
    #endif
    
    	spin_lock(&i->lock);
    
    	l = i->head;
    	do {
    		struct uart_sio_port *up;
    		unsigned int sts;
    
    		up = list_entry(l, struct uart_sio_port, list);
    
    		sts = sio_in(up, SIOSTS);
    		if (sts & 0x5) {
    			spin_lock(&up->port.lock);
    			m32r_sio_handle_port(up, sts, regs);
    			spin_unlock(&up->port.lock);
    
    			end = NULL;
    		} else if (end == NULL)
    			end = l;
    
    		l = l->next;
    
    		if (l == i->head && pass_counter++ > PASS_LIMIT) {
    			if (sts & 0xe0)
    				sio_error(&sts);
    			break;
    		}
    	} while (l != end);
    
    	spin_unlock(&i->lock);
    
    	DEBUG_INTR("end.\n");
    
    	return IRQ_HANDLED;
    }
    
    /*
     * To support ISA shared interrupts, we need to have one interrupt
     * handler that ensures that the IRQ line has been deasserted
     * before returning.  Failing to do this will result in the IRQ
     * line being stuck active, and, since ISA irqs are edge triggered,
     * no more IRQs will be seen.
     */
    static void serial_do_unlink(struct irq_info *i, struct uart_sio_port *up)
    {
    	spin_lock_irq(&i->lock);
    
    	if (!list_empty(i->head)) {
    		if (i->head == &up->list)
    			i->head = i->head->next;
    		list_del(&up->list);
    	} else {
    		BUG_ON(i->head != &up->list);
    		i->head = NULL;
    	}
    
    	spin_unlock_irq(&i->lock);
    }
    
    static int serial_link_irq_chain(struct uart_sio_port *up)
    {
    	struct irq_info *i = irq_lists + up->port.irq;
    	int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? SA_SHIRQ : 0;
    
    	spin_lock_irq(&i->lock);
    
    	if (i->head) {
    		list_add(&up->list, i->head);
    		spin_unlock_irq(&i->lock);
    
    		ret = 0;
    	} else {
    		INIT_LIST_HEAD(&up->list);
    		i->head = &up->list;
    		spin_unlock_irq(&i->lock);
    
    		ret = request_irq(up->port.irq, m32r_sio_interrupt,
    				  irq_flags, "SIO0-RX", i);
    		ret |= request_irq(up->port.irq + 1, m32r_sio_interrupt,
    				  irq_flags, "SIO0-TX", i);
    		if (ret < 0)
    			serial_do_unlink(i, up);
    	}
    
    	return ret;
    }
    
    static void serial_unlink_irq_chain(struct uart_sio_port *up)
    {
    	struct irq_info *i = irq_lists + up->port.irq;
    
    	BUG_ON(i->head == NULL);
    
    	if (list_empty(i->head)) {
    		free_irq(up->port.irq, i);
    		free_irq(up->port.irq + 1, i);
    	}
    
    	serial_do_unlink(i, up);
    }
    
    /*
     * This function is used to handle ports that do not have an interrupt.
     */
    static void m32r_sio_timeout(unsigned long data)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)data;
    	unsigned int timeout;
    	unsigned int sts;
    
    	sts = sio_in(up, SIOSTS);
    	if (sts & 0x5) {
    		spin_lock(&up->port.lock);
    		m32r_sio_handle_port(up, sts, NULL);
    		spin_unlock(&up->port.lock);
    	}
    
    	timeout = up->port.timeout;
    	timeout = timeout > 6 ? (timeout / 2 - 2) : 1;
    	mod_timer(&up->timer, jiffies + timeout);
    }
    
    static unsigned int m32r_sio_tx_empty(struct uart_port *port)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    	unsigned long flags;
    	unsigned int ret;
    
    	spin_lock_irqsave(&up->port.lock, flags);
    	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
    	spin_unlock_irqrestore(&up->port.lock, flags);
    
    	return ret;
    }
    
    static unsigned int m32r_sio_get_mctrl(struct uart_port *port)
    {
    	return 0;
    }
    
    static void m32r_sio_set_mctrl(struct uart_port *port, unsigned int mctrl)
    {
    
    }
    
    static void m32r_sio_break_ctl(struct uart_port *port, int break_state)
    {
    
    }
    
    static int m32r_sio_startup(struct uart_port *port)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    	int retval;
    
    	sio_init();
    
    	/*
    	 * If the "interrupt" for this port doesn't correspond with any
    	 * hardware interrupt, we use a timer-based system.  The original
    	 * driver used to do this with IRQ0.
    	 */
    	if (!is_real_interrupt(up->port.irq)) {
    		unsigned int timeout = up->port.timeout;
    
    		timeout = timeout > 6 ? (timeout / 2 - 2) : 1;
    
    		up->timer.data = (unsigned long)up;
    		mod_timer(&up->timer, jiffies + timeout);
    	} else {
    		retval = serial_link_irq_chain(up);
    		if (retval)
    			return retval;
    	}
    
    	/*
    	 * Finally, enable interrupts.  Note: Modem status interrupts
    	 * are set via set_termios(), which will be occurring imminently
    	 * anyway, so we don't enable them here.
    	 * - M32R_SIO: 0x0c
    	 * - M32R_PLDSIO: 0x04
    	 */
    	up->ier = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI;
    	sio_out(up, SIOTRCR, up->ier);
    
    	/*
    	 * And clear the interrupt registers again for luck.
    	 */
    	sio_reset();
    
    	return 0;
    }
    
    static void m32r_sio_shutdown(struct uart_port *port)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    
    	/*
    	 * Disable interrupts from this port
    	 */
    	up->ier = 0;
    	sio_out(up, SIOTRCR, 0);
    
    	/*
    	 * Disable break condition and FIFOs
    	 */
    
    	sio_init();
    
    	if (!is_real_interrupt(up->port.irq))
    		del_timer_sync(&up->timer);
    	else
    		serial_unlink_irq_chain(up);
    }
    
    static unsigned int m32r_sio_get_divisor(struct uart_port *port,
    	unsigned int baud)
    {
    	return uart_get_divisor(port, baud);
    }
    
    static void m32r_sio_set_termios(struct uart_port *port,
    	struct termios *termios, struct termios *old)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    	unsigned char cval = 0;
    	unsigned long flags;
    	unsigned int baud, quot;
    
    	switch (termios->c_cflag & CSIZE) {
    	case CS5:
    		cval = UART_LCR_WLEN5;
    		break;
    	case CS6:
    		cval = UART_LCR_WLEN6;
    		break;
    	case CS7:
    		cval = UART_LCR_WLEN7;
    		break;
    	default:
    	case CS8:
    		cval = UART_LCR_WLEN8;
    		break;
    	}
    
    	if (termios->c_cflag & CSTOPB)
    		cval |= UART_LCR_STOP;
    	if (termios->c_cflag & PARENB)
    		cval |= UART_LCR_PARITY;
    	if (!(termios->c_cflag & PARODD))
    		cval |= UART_LCR_EPAR;
    #ifdef CMSPAR
    	if (termios->c_cflag & CMSPAR)
    		cval |= UART_LCR_SPAR;
    #endif
    
    	/*
    	 * Ask the core to calculate the divisor for us.
    	 */
    #ifdef CONFIG_SERIAL_M32R_PLDSIO
    	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/4);
    #else
    	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
    #endif
    	quot = m32r_sio_get_divisor(port, baud);
    
    	/*
    	 * Ok, we're now changing the port state.  Do it with
    	 * interrupts disabled.
    	 */
    	spin_lock_irqsave(&up->port.lock, flags);
    
    	sio_set_baud_rate(baud);
    
    	/*
    	 * Update the per-port timeout.
    	 */
    	uart_update_timeout(port, termios->c_cflag, baud);
    
    	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
    	if (termios->c_iflag & INPCK)
    		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
    	if (termios->c_iflag & (BRKINT | PARMRK))
    		up->port.read_status_mask |= UART_LSR_BI;
    
    	/*
    	 * Characteres to ignore
    	 */
    	up->port.ignore_status_mask = 0;
    	if (termios->c_iflag & IGNPAR)
    		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
    	if (termios->c_iflag & IGNBRK) {
    		up->port.ignore_status_mask |= UART_LSR_BI;
    		/*
    		 * If we're ignoring parity and break indicators,
    		 * ignore overruns too (for real raw support).
    		 */
    		if (termios->c_iflag & IGNPAR)
    			up->port.ignore_status_mask |= UART_LSR_OE;
    	}
    
    	/*
    	 * ignore all characters if CREAD is not set
    	 */
    	if ((termios->c_cflag & CREAD) == 0)
    		up->port.ignore_status_mask |= UART_LSR_DR;
    
    	/*
    	 * CTS flow control flag and modem status interrupts
    	 */
    	up->ier &= ~UART_IER_MSI;
    	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
    		up->ier |= UART_IER_MSI;
    
    	serial_out(up, UART_IER, up->ier);
    
    	up->lcr = cval;					/* Save LCR */
    	spin_unlock_irqrestore(&up->port.lock, flags);
    }
    
    static void m32r_sio_pm(struct uart_port *port, unsigned int state,
    	unsigned int oldstate)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    
    	if (up->pm)
    		up->pm(port, state, oldstate);
    }
    
    /*
     * Resource handling.  This is complicated by the fact that resources
     * depend on the port type.  Maybe we should be claiming the standard
     * 8250 ports, and then trying to get other resources as necessary?
     */
    static int
    m32r_sio_request_std_resource(struct uart_sio_port *up, struct resource **res)
    {
    	unsigned int size = 8 << up->port.regshift;
    #ifndef CONFIG_SERIAL_M32R_PLDSIO
    	unsigned long start;
    #endif
    	int ret = 0;
    
    	switch (up->port.iotype) {
    	case UPIO_MEM:
    		if (up->port.mapbase) {
    #ifdef CONFIG_SERIAL_M32R_PLDSIO
    			*res = request_mem_region(up->port.mapbase, size, "serial");
    #else
    			start = up->port.mapbase;
    			*res = request_mem_region(start, size, "serial");
    #endif
    			if (!*res)
    				ret = -EBUSY;
    		}
    		break;
    
    	case UPIO_PORT:
    		*res = request_region(up->port.iobase, size, "serial");
    		if (!*res)
    			ret = -EBUSY;
    		break;
    	}
    	return ret;
    }
    
    static void m32r_sio_release_port(struct uart_port *port)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    	unsigned long start, offset = 0, size = 0;
    
    	size <<= up->port.regshift;
    
    	switch (up->port.iotype) {
    	case UPIO_MEM:
    		if (up->port.mapbase) {
    			/*
    			 * Unmap the area.
    			 */
    			iounmap(up->port.membase);
    			up->port.membase = NULL;
    
    			start = up->port.mapbase;
    
    			if (size)
    				release_mem_region(start + offset, size);
    			release_mem_region(start, 8 << up->port.regshift);
    		}
    		break;
    
    	case UPIO_PORT:
    		start = up->port.iobase;
    
    		if (size)
    			release_region(start + offset, size);
    		release_region(start + offset, 8 << up->port.regshift);
    		break;
    
    	default:
    		break;
    	}
    }
    
    static int m32r_sio_request_port(struct uart_port *port)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    	struct resource *res = NULL;
    	int ret = 0;
    
    	ret = m32r_sio_request_std_resource(up, &res);
    
    	/*
    	 * If we have a mapbase, then request that as well.
    	 */
    	if (ret == 0 && up->port.flags & UPF_IOREMAP) {
    		int size = res->end - res->start + 1;
    
    		up->port.membase = ioremap(up->port.mapbase, size);
    		if (!up->port.membase)
    			ret = -ENOMEM;
    	}
    
    	if (ret < 0) {
    		if (res)
    			release_resource(res);
    	}
    
    	return ret;
    }
    
    static void m32r_sio_config_port(struct uart_port *port, int flags)
    {
    	struct uart_sio_port *up = (struct uart_sio_port *)port;
    
    	spin_lock_irqsave(&up->port.lock, flags);
    
    	up->port.type = (PORT_M32R_SIO - PORT_M32R_BASE + 1);
    	up->port.fifosize = uart_config[up->port.type].dfl_xmit_fifo_size;
    
    	spin_unlock_irqrestore(&up->port.lock, flags);
    }
    
    static int
    m32r_sio_verify_port(struct uart_port *port, struct serial_struct *ser)
    {
    	if (ser->irq >= NR_IRQS || ser->irq < 0 ||
    	    ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
    	    ser->type >= ARRAY_SIZE(uart_config))
    		return -EINVAL;
    	return 0;
    }
    
    static const char *
    m32r_sio_type(struct uart_port *port)
    {
    	int type = port->type;
    
    	if (type >= ARRAY_SIZE(uart_config))
    		type = 0;
    	return uart_config[type].name;
    }
    
    static struct uart_ops m32r_sio_pops = {
    	.tx_empty	= m32r_sio_tx_empty,
    	.set_mctrl	= m32r_sio_set_mctrl,
    	.get_mctrl	= m32r_sio_get_mctrl,
    	.stop_tx	= m32r_sio_stop_tx,
    	.start_tx	= m32r_sio_start_tx,
    	.stop_rx	= m32r_sio_stop_rx,
    	.enable_ms	= m32r_sio_enable_ms,
    	.break_ctl	= m32r_sio_break_ctl,
    	.startup	= m32r_sio_startup,
    	.shutdown	= m32r_sio_shutdown,
    	.set_termios	= m32r_sio_set_termios,
    	.pm		= m32r_sio_pm,
    	.type		= m32r_sio_type,
    	.release_port	= m32r_sio_release_port,
    	.request_port	= m32r_sio_request_port,
    	.config_port	= m32r_sio_config_port,
    	.verify_port	= m32r_sio_verify_port,
    };
    
    static struct uart_sio_port m32r_sio_ports[UART_NR];
    
    static void __init m32r_sio_init_ports(void)
    {
    	struct uart_sio_port *up;
    	static int first = 1;
    	int i;
    
    	if (!first)
    		return;
    	first = 0;
    
    	for (i = 0, up = m32r_sio_ports; i < ARRAY_SIZE(old_serial_port);
    	     i++, up++) {
    		up->port.iobase   = old_serial_port[i].port;
    		up->port.irq      = irq_canonicalize(old_serial_port[i].irq);
    		up->port.uartclk  = old_serial_port[i].baud_base * 16;
    		up->port.flags    = old_serial_port[i].flags;
    		up->port.membase  = old_serial_port[i].iomem_base;
    		up->port.iotype   = old_serial_port[i].io_type;
    		up->port.regshift = old_serial_port[i].iomem_reg_shift;
    		up->port.ops      = &m32r_sio_pops;
    	}
    }
    
    static void __init m32r_sio_register_ports(struct uart_driver *drv)
    {
    	int i;
    
    	m32r_sio_init_ports();
    
    	for (i = 0; i < UART_NR; i++) {
    		struct uart_sio_port *up = &m32r_sio_ports[i];
    
    		up->port.line = i;
    		up->port.ops = &m32r_sio_pops;
    		init_timer(&up->timer);
    		up->timer.function = m32r_sio_timeout;
    
    		/*
    		 * ALPHA_KLUDGE_MCR needs to be killed.
    		 */
    		up->mcr_mask = ~ALPHA_KLUDGE_MCR;
    		up->mcr_force = ALPHA_KLUDGE_MCR;
    
    		uart_add_one_port(drv, &up->port);
    	}
    }
    
    #ifdef CONFIG_SERIAL_M32R_SIO_CONSOLE
    
    /*
     *	Wait for transmitter & holding register to empty
     */
    static inline void wait_for_xmitr(struct uart_sio_port *up)
    {
    	unsigned int status, tmout = 10000;
    
    	/* Wait up to 10ms for the character(s) to be sent. */
    	do {
    		status = sio_in(up, SIOSTS);
    
    		if (--tmout == 0)
    			break;
    		udelay(1);
    	} while ((status & UART_EMPTY) != UART_EMPTY);
    
    	/* Wait up to 1s for flow control if necessary */
    	if (up->port.flags & UPF_CONS_FLOW) {
    		tmout = 1000000;
    		while (--tmout)
    			udelay(1);
    	}
    }
    
    /*
     *	Print a string to the serial port trying not to disturb
     *	any possible real use of the port...
     *
     *	The console_lock must be held when we get here.
     */
    static void m32r_sio_console_write(struct console *co, const char *s,
    	unsigned int count)
    {
    	struct uart_sio_port *up = &m32r_sio_ports[co->index];
    	unsigned int ier;
    	int i;
    
    	/*
    	 *	First save the UER then disable the interrupts
    	 */
    	ier = sio_in(up, SIOTRCR);
    	sio_out(up, SIOTRCR, 0);
    
    	/*
    	 *	Now, do each character
    	 */
    	for (i = 0; i < count; i++, s++) {
    		wait_for_xmitr(up);
    
    		/*
    		 *	Send the character out.
    		 *	If a LF, also do CR...
    		 */
    		sio_out(up, SIOTXB, *s);
    
    		if (*s == 10) {
    			wait_for_xmitr(up);
    			sio_out(up, SIOTXB, 13);
    		}
    	}
    
    	/*
    	 *	Finally, wait for transmitter to become empty
    	 *	and restore the IER
    	 */
    	wait_for_xmitr(up);
    	sio_out(up, SIOTRCR, ier);
    }
    
    static int __init m32r_sio_console_setup(struct console *co, char *options)
    {
    	struct uart_port *port;
    	int baud = 9600;
    	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.
    	 */
    	if (co->index >= UART_NR)
    		co->index = 0;
    	port = &m32r_sio_ports[co->index].port;
    
    	/*
    	 * Temporary fix.
    	 */
    	spin_lock_init(&port->lock);
    
    	if (options)
    		uart_parse_options(options, &baud, &parity, &bits, &flow);
    
    	return uart_set_options(port, co, baud, parity, bits, flow);
    }
    
    extern struct uart_driver m32r_sio_reg;
    static struct console m32r_sio_console = {
    	.name		= "ttyS",
    	.write		= m32r_sio_console_write,
    	.device		= uart_console_device,
    	.setup		= m32r_sio_console_setup,
    	.flags		= CON_PRINTBUFFER,
    	.index		= -1,
    	.data		= &m32r_sio_reg,
    };
    
    static int __init m32r_sio_console_init(void)
    {
    	sio_reset();
    	sio_init();
    	m32r_sio_init_ports();
    	register_console(&m32r_sio_console);
    	return 0;
    }
    console_initcall(m32r_sio_console_init);
    
    #define M32R_SIO_CONSOLE	&m32r_sio_console
    #else
    #define M32R_SIO_CONSOLE	NULL
    #endif
    
    static struct uart_driver m32r_sio_reg = {
    	.owner			= THIS_MODULE,
    	.driver_name		= "sio",
    	.devfs_name		= "tts/",
    	.dev_name		= "ttyS",
    	.major			= TTY_MAJOR,
    	.minor			= 64,
    	.nr			= UART_NR,
    	.cons			= M32R_SIO_CONSOLE,
    };
    
    /**
     *	m32r_sio_suspend_port - suspend one serial port
     *	@line: serial line number
     *
     *	Suspend one serial port.
     */
    void m32r_sio_suspend_port(int line)
    {
    	uart_suspend_port(&m32r_sio_reg, &m32r_sio_ports[line].port);
    }
    
    /**
     *	m32r_sio_resume_port - resume one serial port
     *	@line: serial line number
     *
     *	Resume one serial port.
     */
    void m32r_sio_resume_port(int line)
    {
    	uart_resume_port(&m32r_sio_reg, &m32r_sio_ports[line].port);
    }
    
    static int __init m32r_sio_init(void)
    {
    	int ret, i;
    
    	printk(KERN_INFO "Serial: M32R SIO driver $Revision: 1.11 $ ");
    
    	for (i = 0; i < NR_IRQS; i++)
    		spin_lock_init(&irq_lists[i].lock);
    
    	ret = uart_register_driver(&m32r_sio_reg);
    	if (ret >= 0)
    		m32r_sio_register_ports(&m32r_sio_reg);
    
    	return ret;
    }
    
    static void __exit m32r_sio_exit(void)
    {
    	int i;
    
    	for (i = 0; i < UART_NR; i++)
    		uart_remove_one_port(&m32r_sio_reg, &m32r_sio_ports[i].port);
    
    	uart_unregister_driver(&m32r_sio_reg);
    }
    
    module_init(m32r_sio_init);
    module_exit(m32r_sio_exit);
    
    EXPORT_SYMBOL(m32r_sio_suspend_port);
    EXPORT_SYMBOL(m32r_sio_resume_port);
    
    MODULE_LICENSE("GPL");
    MODULE_DESCRIPTION("Generic M32R SIO serial driver $Revision: 1.11 $");