vacserial.c

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#endif
	if (retval)
		return retval;
	info->flags |= ASYNC_NORMAL_ACTIVE;
	return 0;
}

static int get_async_struct(int line, struct async_struct **ret_info)
{
	struct async_struct *info;
	struct serial_state *sstate;

	sstate = rs_table + line;
	sstate->count++;
	if (sstate->info) {
		*ret_info = sstate->info;
		return 0;
	}
	info = kmalloc(sizeof(struct async_struct), GFP_KERNEL);
	if (!info) {
		sstate->count--;
		return -ENOMEM;
	}
	memset(info, 0, sizeof(struct async_struct));
	init_waitqueue_head(&info->open_wait);
	init_waitqueue_head(&info->close_wait);
	init_waitqueue_head(&info->delta_msr_wait);
	info->magic = SERIAL_MAGIC;
	info->port = sstate->port;
	info->flags = sstate->flags;
	info->xmit_fifo_size = sstate->xmit_fifo_size;
	info->line = line;
	info->tqueue.routine = do_softint;
	info->tqueue.data = info;
	info->state = sstate;
	if (sstate->info) {
		kfree(info);
		*ret_info = sstate->info;
		return 0;
	}
	*ret_info = sstate->info = info;
	return 0;
}

/*
 * This routine is called whenever a serial port is opened.  It
 * enables interrupts for a serial port, linking in its async structure into
 * the IRQ chain.   It also performs the serial-specific
 * initialization for the tty structure.
 */
static int rs_open(struct tty_struct *tty, struct file * filp)
{
	struct async_struct	*info;
	int 			retval, line;
	unsigned long		page;

	MOD_INC_USE_COUNT; 
	line = MINOR(tty->device) - tty->driver.minor_start;
	if ((line < 0) || (line >= NR_PORTS)) {
		MOD_DEC_USE_COUNT; 
		return -ENODEV;
	}
	retval = get_async_struct(line, &info);
	if (retval) {
		MOD_DEC_USE_COUNT;
		return retval;
	}
        tty->driver_data = info;
        info->tty = tty;
	if (serial_paranoia_check(info, tty->device, "rs_open")) {
	        /* MOD_DEC_USE_COUNT; "info->tty" will cause this */ 
		return -ENODEV;
	}

#ifdef SERIAL_DEBUG_OPEN
	baget_printk("rs_open %s%d, count = %d\n", 
		     tty->driver.name, info->line,
		     info->state->count);
#endif
	info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;

	if (!tmp_buf) {
		page = get_free_page(GFP_KERNEL);
		if (!page) {
			/* MOD_DEC_USE_COUNT; "info->tty" will cause this */
			return -ENOMEM;
		}
		if (tmp_buf)
			free_page(page);
		else
			tmp_buf = (unsigned char *) page;
	}

	/*
	 * If the port is the middle of closing, bail out now
	 */
	if (tty_hung_up_p(filp) ||
	    (info->flags & ASYNC_CLOSING)) {
		if (info->flags & ASYNC_CLOSING)
			interruptible_sleep_on(&info->close_wait);
		/* MOD_DEC_USE_COUNT; "info->tty" will cause this */
#ifdef SERIAL_DO_RESTART
		return ((info->flags & ASYNC_HUP_NOTIFY) ?
			-EAGAIN : -ERESTARTSYS);
#else
		return -EAGAIN;
#endif
	}

	/*
	 * Start up serial port
	 */
	retval = startup(info);
	if (retval) {
		/* MOD_DEC_USE_COUNT; "info->tty" will cause this */
		return retval;
	}

	retval = block_til_ready(tty, filp, info);
	if (retval) {
		 /* MOD_DEC_USE_COUNT; "info->tty" will cause this */
#ifdef SERIAL_DEBUG_OPEN
		 baget_printk("rs_open returning after block_til_ready "
			      "with %d\n",
			      retval);
#endif
		 return retval;
	}

	if ((info->state->count == 1) &&
	    (info->flags & ASYNC_SPLIT_TERMIOS)) {
		if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
			*tty->termios = info->state->normal_termios;
		else 
			*tty->termios = info->state->callout_termios;
		change_speed(info);
	}
#ifdef CONFIG_SERIAL_CONSOLE
	if (sercons.cflag && sercons.index == line) {
		tty->termios->c_cflag = sercons.cflag;
		sercons.cflag = 0;
		change_speed(info);
	}
#endif
	info->session = current->session;
	info->pgrp = current->pgrp;

#ifdef SERIAL_DEBUG_OPEN
	baget_printk("rs_open ttys%d successful...", info->line);
#endif
	return 0;
}

/*
 * /proc fs routines....
 */

static inline int line_info(char *buf, struct serial_state *state)
{
	struct async_struct *info = state->info, scr_info;
	int	ret;

	ret = sprintf(buf, "%d: uart:%s port:%X irq:%d",
		      state->line, uart_config[state->type].name, 
		      state->port, state->irq);

	if (!state->port || (state->type == PORT_UNKNOWN)) {
		ret += sprintf(buf+ret, "\n");
		return ret;
	}

	/*
	 * Figure out the current RS-232 lines
	 */
	if (!info) {
		info = &scr_info;	/* This is just for serial_{in,out} */

		info->magic = SERIAL_MAGIC;
		info->port = state->port;
		info->flags = state->flags;
		info->quot = 0;
		info->tty = 0;
	}
	
	if (info->quot) {
		ret += sprintf(buf+ret, " baud:%d",
			       state->baud_base / info->quot);
	}

	ret += sprintf(buf+ret, " tx:%d rx:%d",
		      state->icount.tx, state->icount.rx);

	if (state->icount.frame)
		ret += sprintf(buf+ret, " fe:%d", state->icount.frame);
	
	if (state->icount.parity)
		ret += sprintf(buf+ret, " pe:%d", state->icount.parity);
	
	if (state->icount.brk)
		ret += sprintf(buf+ret, " brk:%d", state->icount.brk);	

	if (state->icount.overrun)
		ret += sprintf(buf+ret, " oe:%d", state->icount.overrun);

	return ret;
}

int rs_read_proc(char *page, char **start, off_t off, int count,
		 int *eof, void *data)
{
	int i, len = 0, l;
	off_t	begin = 0;

	len += sprintf(page, "serinfo:1.0 driver:%s\n", serial_version);
	for (i = 0; i < NR_PORTS && len < 4000; i++) {
                l = line_info(page + len, &rs_table[i]);
                len += l;
 		if (len+begin > off+count)
			goto done;
		if (len+begin < off) {
			begin += len;
			len = 0;
		}
	}
	*eof = 1;
done:
	if (off >= len+begin)
		return 0;
	*start = page + (off-begin);
	return ((count < begin+len-off) ? count : begin+len-off);
}

/*
 * ---------------------------------------------------------------------
 * rs_init() and friends
 *
 * rs_init() is called at boot-time to initialize the serial driver.
 * ---------------------------------------------------------------------
 */

/*
 * This routine prints out the appropriate serial driver version
 * number, and identifies which options were configured into this
 * driver.
 */
static _INLINE_ void show_serial_version(void)
{
 	printk(KERN_INFO "%s version %s with", serial_name, serial_version);
#ifdef CONFIG_SERIAL_SHARE_IRQ
	printk(" SHARE_IRQ");
#endif
#define SERIAL_OPT
#ifdef CONFIG_SERIAL_DETECT_IRQ
	printk(" DETECT_IRQ");
#endif
#ifdef SERIAL_OPT
	printk(" enabled\n");
#else
	printk(" no serial options enabled\n");
#endif
#undef SERIAL_OPT
}


/*
 * This routine is called by rs_init() to initialize a specific serial
 * port.  It determines what type of UART chip this serial port is
 * using: 8250, 16450, 16550, 16550A.  The important question is
 * whether or not this UART is a 16550A or not, since this will
 * determine whether or not we can use its FIFO features or not.
 */

/*
 *  Functionality of this function is reduced: we already know we have a VAC,
 *  but still need to perform some important actions (see code :-).
 */
static void autoconfig(struct serial_state * state)
{
	struct async_struct *info, scr_info; 
	unsigned long flags;

	/* Setting up important parameters */
	state->type = VAC_UART_TYPE;
	state->xmit_fifo_size = uart_config[state->type].dfl_xmit_fifo_size;

	info = &scr_info;       /* This is just for serial_{in,out} */   

	info->magic = SERIAL_MAGIC;
        info->port  = state->port;
        info->flags = state->flags;

        save_flags(flags); cli();

	/* + Flush VAC input fifo */ 
        (void)serial_in(info, VAC_UART_RX);
        (void)serial_in(info, VAC_UART_RX);
        (void)serial_in(info, VAC_UART_RX);
        (void)serial_in(info, VAC_UART_RX);

	/* Disable interrupts */
        serial_outp(info, VAC_UART_INT_MASK, 0);

        restore_flags(flags);
}

int register_serial(struct serial_struct *req);
void unregister_serial(int line);

EXPORT_SYMBOL(register_serial);
EXPORT_SYMBOL(unregister_serial);

/*
 *  Important function for VAC UART check and reanimation.
 */

static void rs_timer(unsigned long dummy)
{
        static unsigned long last_strobe = 0;
        struct async_struct *info;
        unsigned int    i;
        unsigned long flags;

        if ((jiffies - last_strobe) >= RS_STROBE_TIME) {
                for (i=1; i < NR_IRQS; i++) {
                        info = IRQ_ports[i];
                        if (!info)
                                continue;
                        save_flags(flags); cli();
#ifdef CONFIG_SERIAL_SHARE_IRQ
                        if (info->next_port) {
                                do {
                                        serial_out(info, VAC_UART_INT_MASK, 0);
                                        info->IER |= VAC_UART_INT_TX_EMPTY;
                                        serial_out(info, VAC_UART_INT_MASK, 
						   info->IER);
                                        info = info->next_port;
                                } while (info);
				rs_interrupt(i, NULL, NULL);
                        } else
#endif /* CONFIG_SERIAL_SHARE_IRQ */
                                rs_interrupt_single(i, NULL, NULL);
                        restore_flags(flags);
                }
        }
        last_strobe = jiffies;
        mod_timer(&vacs_timer, jiffies + RS_STROBE_TIME);

	/*
	 *  It looks this code for case we share IRQ with console...
	 */

        if (IRQ_ports[0]) {
                save_flags(flags); cli();
#ifdef CONFIG_SERIAL_SHARE_IRQ
                rs_interrupt(0, NULL, NULL);
#else
                rs_interrupt_single(0, NULL, NULL);
#endif
                restore_flags(flags);

                mod_timer(&vacs_timer, jiffies + IRQ_timeout[0] - 2);
        }
}
 
/*
 * The serial driver boot-time initialization code!
 */
int __init rs_init(void)
{
	int i;
	struct serial_state * state;
	extern void atomwide_serial_init (void);
	extern void dualsp_serial_init (void);

#ifdef CONFIG_ATOMWIDE_SERIAL
	atomwide_serial_init ();
#endif
#ifdef CONFIG_DUALSP_SERIAL
	dualsp_serial_init ();
#endif

	init_bh(SERIAL_BH, do_serial_bh);
	init_timer(&vacs_timer);
	vacs_timer.function = rs_timer;
	vacs_timer.expires = 0;

	for (i = 0; i < NR_IRQS; i++) {
		IRQ_ports[i] = 0;
		IRQ_timeout[i] = 0;
	}


/*
 *  It is not a good idea to share interrupts with console,
 *  but it looks we cannot avoid it.
 */
#if 0 

#ifdef CONFIG_SERIAL_CONSOLE
	/*
	 *	The interrupt of the serial console port
	 *	can't be shared.
	 */
	if (sercons.flags & CON_CONSDEV) {
		for(i = 0; i < NR_PORTS; i++)
			if (i != sercons.index &&
			    rs_table[i].irq == rs_table[sercons.index].irq)
				rs_table[i].irq = 0;
	}
#endif

#endif
	show_serial_version();

	/* Initialize the tty_driver structure */
	
	memset(&serial_driver, 0, sizeof(struct tty_driver));
	serial_driver.magic = TTY_DRIVER_MAGIC;
	serial_driver.driver_name = "serial";
	serial_driver.name = "ttyS";
	serial_driver.major = TTY_MAJOR;
	serial_driver.minor_start = 64;
	serial_driver.num = NR_PORTS;
	serial_driver.type = TTY_DRIVER_TYPE_SERIAL;
	serial_driver.subtype = SERIAL_TYPE_NORMAL;
	serial_driver.init_termios = tty_std_termios;
	serial_driver.init_termios.c_cflag =
		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
	serial_driver.flags = TTY_DRIVER_REAL_RAW;
	serial_driver.refcount = &serial_refcount;
	serial_driver.table = serial_table;
	serial_driver.termios = serial_termios;
	serial_driver.termios_locked = serial_termios_locked;

	serial_driver.open = rs_open;
	serial_driver.close = rs_close;
	serial_driver.write = rs_write;
	serial_driver.put_char = rs_put_char;
	serial_driver.flush_chars = rs_flush_chars;
	serial_driver.write_room = rs_write_room;
	serial_driver.chars_in_buffer = rs_chars_in_buffer;
	serial_driver.flush_buffer = rs_flush_buffer;
	serial_driver.ioctl = rs_ioctl;
	serial_driver.throttle = rs_throttle;
	serial_driver.unthrottle = rs_unthrottle;
	serial_driver.send_xchar = rs_send_xchar;
	serial_driver.set_termios = rs_set_termios;
	serial_driver.stop = rs_stop;
	serial_driver.start = rs_start;
	serial_driver.hangup = rs_hangup;
	serial_driver.break_ctl = rs_break;
	serial_driver.wait_until_sent = rs_wait_until_sent;
	serial_driver.read_proc = rs_read_proc;
	
	/*
	 * The callout device is just like normal device except for
	 * major number and the subtype code.
	 */
	callout_driver = serial_driver;
	callout_driver.name = "cua";
	callout_driver.major = TTYAUX_MAJOR;
	callout_driver.subtype = SERIAL_TYPE_CALLOUT;
	callout_driver.read_proc = 0;
	callout_driver.proc_entry = 0;

	if (tty_register_driver(&serial_driver))
		panic("Couldn't register serial driver\n");
	if (tty_register_driver(&callout_driver))
		panic("Couldn't register callout driver\n");
	
	for (i = 0, state = rs_table; i < NR_PORTS; i++,state++) {
		state->magic = SSTATE_MAGIC;
		state->line = i;
		state->type = PORT_UNKNOWN;
		state->custom_divisor = 0;
		state->close_delay = 5*HZ/10;
		state->closing_wait = 30*HZ;
		state->callout_termios = callout_driver.init_termios;
		state->normal_termios = serial_driver.init_termios;
		state->icount.cts = state->icount.dsr = 
			state->icount.rng = state->icount.dcd = 0;
		state->icount.rx = state->icount.tx = 0;
		state->icount.frame = state->icount.parity = 0;
		state->icount.overrun = state->icount.brk = 0;
		state->irq = irq_cannonicalize(state->irq);