dz.c

linux和2410结合开发 用他可以生成2410所需的zImage文件

		info->count = 0;
	}

	if (info->count) {
		restore_flags(flags);
		return;
	}
	info->flags |= DZ_CLOSING;
	/*
	 * Save the termios structure, since this port may have
	 * separate termios for callout and dialin.
	 */
	if (info->flags & DZ_NORMAL_ACTIVE)
		info->normal_termios = *tty->termios;
	if (info->flags & DZ_CALLOUT_ACTIVE)
		info->callout_termios = *tty->termios;
	/*
	 * Now we wait for the transmit buffer to clear; and we notify the line
	 * discipline to only process XON/XOFF characters.
	 */
	tty->closing = 1;

	if (info->closing_wait != DZ_CLOSING_WAIT_NONE)
		tty_wait_until_sent(tty, info->closing_wait);

	/*
	 * At this point we stop accepting input.  To do this, we disable the
	 * receive line status interrupts.
	 */
	shutdown(info);

	if (tty->driver.flush_buffer)
		tty->driver.flush_buffer (tty);
	if (tty->ldisc.flush_buffer)
		tty->ldisc.flush_buffer (tty);
	tty->closing = 0;
	info->event = 0;
	info->tty = 0;

	if (tty->ldisc.num != ldiscs[N_TTY].num) {
		if (tty->ldisc.close)
			tty->ldisc.close(tty);
		tty->ldisc = ldiscs[N_TTY];
		tty->termios->c_line = N_TTY;
		if (tty->ldisc.open)
			tty->ldisc.open(tty);
	}
	if (info->blocked_open) {
		if (info->close_delay) {
			current->state = TASK_INTERRUPTIBLE;
			schedule_timeout(info->close_delay);
		}
		wake_up_interruptible(&info->open_wait);
	}

	info->flags &= ~(DZ_NORMAL_ACTIVE | DZ_CALLOUT_ACTIVE | DZ_CLOSING);
	wake_up_interruptible(&info->close_wait);

	restore_flags(flags);
}

/*
 * dz_hangup () --- called by tty_hangup() when a hangup is signaled.
 */
static void dz_hangup (struct tty_struct *tty)
{
	struct dz_serial *info = (struct dz_serial *) tty->driver_data;
  
	dz_flush_buffer(tty);
	shutdown(info);
	info->event = 0;
	info->count = 0;
	info->flags &= ~(DZ_NORMAL_ACTIVE | DZ_CALLOUT_ACTIVE);
	info->tty = 0;
	wake_up_interruptible(&info->open_wait);
}

/*
 * ------------------------------------------------------------
 * rs_open() and friends
 * ------------------------------------------------------------
 */
static int block_til_ready(struct tty_struct *tty, struct file *filp,
                           struct dz_serial *info)
{
	DECLARE_WAITQUEUE(wait, current); 
	int retval;
	int do_clocal = 0;

	/*
	 * If the device is in the middle of being closed, then block
	 * until it's done, and then try again.
	 */
	if (info->flags & DZ_CLOSING) {
		interruptible_sleep_on(&info->close_wait);
		return -EAGAIN;
	}

	/*
	 * If this is a callout device, then just make sure the normal
	 * device isn't being used.
	 */
	if (tty->driver.subtype == SERIAL_TYPE_CALLOUT) {
		if (info->flags & DZ_NORMAL_ACTIVE)
			return -EBUSY;
    
		if ((info->flags & DZ_CALLOUT_ACTIVE) &&
		    (info->flags & DZ_SESSION_LOCKOUT) &&
		    (info->session != current->session))
			return -EBUSY;
    
		if ((info->flags & DZ_CALLOUT_ACTIVE) &&
		    (info->flags & DZ_PGRP_LOCKOUT) &&
		    (info->pgrp != current->pgrp))
			return -EBUSY;

		info->flags |= DZ_CALLOUT_ACTIVE;
		return 0;
	}

	/*
	 * If non-blocking mode is set, or the port is not enabled, then make
	 * the check up front and then exit.
	 */
	if ((filp->f_flags & O_NONBLOCK) ||
	    (tty->flags & (1 << TTY_IO_ERROR))) {
		if (info->flags & DZ_CALLOUT_ACTIVE)
			return -EBUSY;
		info->flags |= DZ_NORMAL_ACTIVE;

		return 0;
	}

	if (info->flags & DZ_CALLOUT_ACTIVE) {
		if (info->normal_termios.c_cflag & CLOCAL)
			do_clocal = 1;
	} else {
		if (tty->termios->c_cflag & CLOCAL)
		do_clocal = 1;
	}

	/*
	 * Block waiting for the carrier detect and the line to become free
	 * (i.e., not in use by the callout).  While we are in this loop,
	 * info->count is dropped by one, so that dz_close() knows when to free
	 * things.  We restore it upon exit, either normal or abnormal.
	 */
	retval = 0;
	add_wait_queue(&info->open_wait, &wait);

	info->count--;
	info->blocked_open++;
	while (1) {
		set_current_state(TASK_INTERRUPTIBLE);
		if (tty_hung_up_p (filp) || !(info->is_initialized)) {
			retval = -EAGAIN;
			break;
		}
		if (!(info->flags & DZ_CALLOUT_ACTIVE) &&
		    !(info->flags & DZ_CLOSING) && do_clocal)
			break;
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		schedule();
	}
		
	current->state = TASK_RUNNING;
	remove_wait_queue (&info->open_wait, &wait);
	if (!tty_hung_up_p(filp))
		info->count++;
	info->blocked_open--;

	if (retval)
		return retval;
	info->flags |= DZ_NORMAL_ACTIVE;
	return 0;
}

/*
 * This routine is called whenever a serial port is opened.  It
 * enables interrupts for a serial port. It also performs the 
 * serial-specific initialization for the tty structure.
 */
static int dz_open (struct tty_struct *tty, struct file *filp)
{
	struct dz_serial *info;
	int retval, line;

	line = MINOR(tty->device) - tty->driver.minor_start;

	/*
	 * The dz lines for the mouse/keyboard must be opened using their
	 * respective drivers.
	 */
	if ((line < 0) || (line >= DZ_NB_PORT))
		return -ENODEV;

	if ((line == DZ_KEYBOARD) || (line == DZ_MOUSE))
		return -ENODEV;

	info = lines[line];
	info->count++;

	tty->driver_data = info;
	info->tty = tty;

	/*
	 * Start up serial port
	 */
	retval = startup (info);
	if (retval)
		return retval;

	retval = block_til_ready (tty, filp, info);
	if (retval)
		return retval;

	if ((info->count == 1) && (info->flags & DZ_SPLIT_TERMIOS)) {
		if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
			*tty->termios = info->normal_termios;
		else 
			*tty->termios = info->callout_termios;
		change_speed(info);
	}

	info->session = current->session;
	info->pgrp = current->pgrp;

	return 0;
}

static void show_serial_version (void)
{
	printk("%s%s\n", dz_name, dz_version);
}


int __init dz_init(void)
{
	int i, flags;
	struct dz_serial *info;

	/* Setup base handler, and timer table. */
	init_bh(SERIAL_BH, do_serial_bh);

	show_serial_version();

	memset(&serial_driver, 0, sizeof(struct tty_driver));
	serial_driver.magic = TTY_DRIVER_MAGIC;
#if (LINUX_VERSION_CODE > 0x2032D && defined(CONFIG_DEVFS_FS))
	serial_driver.name = "ttyS";
#else
	serial_driver.name = "tts/%d";
#endif
	serial_driver.major = TTY_MAJOR;
	serial_driver.minor_start = 64;
	serial_driver.num = DZ_NB_PORT;
	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 | TTY_DRIVER_NO_DEVFS;
	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 = dz_open;
	serial_driver.close = dz_close;
	serial_driver.write = dz_write;
	serial_driver.flush_chars = dz_flush_chars;
	serial_driver.write_room = dz_write_room;
	serial_driver.chars_in_buffer = dz_chars_in_buffer;
	serial_driver.flush_buffer = dz_flush_buffer;
	serial_driver.ioctl = dz_ioctl;
	serial_driver.throttle = dz_throttle;
	serial_driver.unthrottle = dz_unthrottle;
	serial_driver.send_xchar = dz_send_xchar;
	serial_driver.set_termios = dz_set_termios;
	serial_driver.stop = dz_stop;
	serial_driver.start = dz_start;
	serial_driver.hangup = dz_hangup;

	/*
	 * The callout device is just like normal device except for major
	 * number and the subtype code.
	 */
	callout_driver = serial_driver;
#if (LINUX_VERSION_CODE > 0x2032D && defined(CONFIG_DEVFS_FS))
	callout_driver.name = "cua";
#else
	callout_driver.name = "cua/%d";
#endif
	callout_driver.major = TTYAUX_MAJOR;
	callout_driver.subtype = SERIAL_TYPE_CALLOUT;

	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");

	save_flags(flags); cli();
	for (i=0; i < DZ_NB_PORT;  i++) {
		info = &multi[i]; 
		lines[i] = info;
		info->magic = SERIAL_MAGIC;

		if ((mips_machtype == MACH_DS23100) ||
		    (mips_machtype == MACH_DS5100)) 
			info->port = (unsigned long) KN01_DZ11_BASE;
		else 
			info->port = (unsigned long) KN02_DZ11_BASE;

		info->line = i;
		info->tty = 0;
		info->close_delay = 50;
		info->closing_wait = 3000;
		info->x_char = 0;
		info->event = 0;
		info->count = 0;
		info->blocked_open = 0;
		info->tqueue.routine = do_softint;
		info->tqueue.data = info;
		info->tqueue_hangup.routine = do_serial_hangup;
		info->tqueue_hangup.data = info;
		info->callout_termios = callout_driver.init_termios;
		info->normal_termios = serial_driver.init_termios;
		init_waitqueue_head(&info->open_wait); 
		init_waitqueue_head(&info->close_wait); 

		/*
		 * If we are pointing to address zero then punt - not correctly
		 * set up in setup.c to handle this.
		 */
		if (! info->port)
			return 0;

		printk("ttyS%02d at 0x%08x (irq = %d)\n", info->line,
		       info->port, SERIAL);

		tty_register_devfs(&serial_driver, 0,
		                   serial_driver.minor_start + info->line);
		tty_register_devfs(&callout_driver, 0,
		                   callout_driver.minor_start + info->line);
	}

	/* Reset the chip */
#ifndef CONFIG_SERIAL_CONSOLE
	{
		int tmp;
		dz_out(info, DZ_CSR, DZ_CLR);
		while ((tmp = dz_in(info,DZ_CSR)) & DZ_CLR);
		wbflush();
  
		/* Enable scanning */
		dz_out(info, DZ_CSR, DZ_MSE); 
	}
#endif
  
	/*
	 * Order matters here... the trick is that flags is updated... in
	 * request_irq - to immediatedly obliterate it is unwise.
	 */
	restore_flags(flags);

	if (request_irq(SERIAL, dz_interrupt, SA_INTERRUPT, "DZ", lines[0]))
		panic("Unable to register DZ interrupt\n");
 
	return 0;
}

#ifdef CONFIG_SERIAL_CONSOLE
static void dz_console_put_char (unsigned char ch)
{
	unsigned long flags;
	int  loops = 2500;
	unsigned short tmp = ch;
	/*
	 * this code sends stuff out to serial device - spinning its wheels and
	 * waiting.
	 */

	/* force the issue - point it at lines[3]*/
	dz_console = &multi[CONSOLE_LINE];

	save_and_cli(flags);

	/* spin our wheels */
	while (((dz_in(dz_console, DZ_CSR) & DZ_TRDY) != DZ_TRDY) &&  loops--)
		;
  
	/* Actually transmit the character. */
	dz_out(dz_console, DZ_TDR, tmp);

	restore_flags(flags); 
}

/* 
 * -------------------------------------------------------------------
 * dz_console_print ()
 *
 * dz_console_print is registered for printk.
 * The console must be locked when we get here.
 * ------------------------------------------------------------------- 
 */
static void dz_console_print (struct console *cons, 
			      const char *str, 
			      unsigned int count)
{
#ifdef DEBUG_DZ
	prom_printf((char *)str);
#endif
	while (count--) {
		if (*str == '\n')
			dz_console_put_char('\r');
		dz_console_put_char(*str++);
	}
}

static int dz_console_wait_key(struct console *co)
{
	return 0;
}

static kdev_t dz_console_device(struct console *c)
{
	return MKDEV(TTY_MAJOR, 64 + c->index);
}

static int __init dz_console_setup(struct console *co, char *options)
{
	int baud = 9600;
	int bits = 8;
	int parity = 'n';
	int cflag = CREAD | HUPCL | CLOCAL;
	char *s;
	unsigned short mask,tmp;

	if (options) {
		baud = simple_strtoul(options, NULL, 10);
		s = options;
		while (*s >= '0' && *s <= '9')
			s++;
		if (*s)
			parity = *s++;
		if (*s)
			bits   = *s - '0';
	}

	/*
	 * Now construct a cflag setting.
	 */
	switch (baud) {
	case 1200:
		cflag |= DZ_B1200;
		break;
	case 2400:
		cflag |= DZ_B2400;
		break;
	case 4800:
		cflag |= DZ_B4800;
		break;
	case 9600:
	default:
		cflag |= DZ_B9600;
		break;
	}
	switch (bits) {
	case 7:
		cflag |= DZ_CS7;
		break;
	default:
	case 8:
		cflag |= DZ_CS8;
		break;
	}
	switch (parity) {
	case 'o':
	case 'O':
		cflag |= DZ_PARODD;
		break;
	case 'e':
	case 'E':
		cflag |= DZ_PARENB;
		break;
	}
	co->cflag = cflag;

	/* TOFIX: force to console line */
	dz_console = &multi[CONSOLE_LINE];
	if ((mips_machtype == MACH_DS23100) || (mips_machtype == MACH_DS5100)) 
		dz_console->port = KN01_DZ11_BASE;
	else 
		dz_console->port = KN02_DZ11_BASE; 
	dz_console->line = CONSOLE_LINE;

	dz_out(dz_console, DZ_CSR, DZ_CLR);
	while ((tmp = dz_in(dz_console,DZ_CSR)) & DZ_CLR)
		;

	/* enable scanning */
	dz_out(dz_console, DZ_CSR, DZ_MSE); 

	/*  Set up flags... */
	dz_console->cflags = 0;
	dz_console->cflags |= DZ_B9600;
	dz_console->cflags |= DZ_CS8;
	dz_console->cflags |= DZ_PARENB;
	dz_out(dz_console, DZ_LPR, dz_console->cflags);

	mask = 1 << dz_console->line;
	tmp = dz_in (dz_console, DZ_TCR);		/* read the TX flag */
	if (!(tmp & mask)) {
		tmp |= mask;				/* set the TX flag */
		dz_out (dz_console, DZ_TCR, tmp); 
	}

	return 0;
}

static struct console dz_sercons = {
    name:	"ttyS",
    write:	dz_console_print,
    device:	dz_console_device,
    wait_key:	dz_console_wait_key,
    setup:	dz_console_setup,
    flags:	CON_CONSDEV | CON_PRINTBUFFER,
    index:	CONSOLE_LINE,
};

void __init dz_serial_console_init(void)
{
	register_console(&dz_sercons);
}

#endif /* ifdef CONFIG_SERIAL_CONSOLE */

MODULE_LICENSE("GPL");