mkiss.c

powerpc内核mpc8241linux系统下net驱动程序

{
	switch (s) {
		case END:
			/* drop keeptest bit = VSV */
			if (test_bit(AXF_KEEPTEST, &ax->flags))
				clear_bit(AXF_KEEPTEST, &ax->flags);

			if (!test_and_clear_bit(AXF_ERROR, &ax->flags) && (ax->rcount > 2))
				ax_bump(ax);

			clear_bit(AXF_ESCAPE, &ax->flags);
			ax->rcount = 0;
			return;

		case ESC:
			set_bit(AXF_ESCAPE, &ax->flags);
			return;
		case ESC_ESC:
			if (test_and_clear_bit(AXF_ESCAPE, &ax->flags))
				s = ESC;
			break;
		case ESC_END:
			if (test_and_clear_bit(AXF_ESCAPE, &ax->flags))
				s = END;
			break;
	}

	if (!test_bit(AXF_ERROR, &ax->flags)) {
		if (ax->rcount < ax->buffsize) {
			ax->rbuff[ax->rcount++] = s;
			return;
		}

		ax->rx_over_errors++;
		set_bit(AXF_ERROR, &ax->flags);
	}
}


int ax_set_mac_address(struct device *dev, void *addr)
{
	if (copy_from_user(dev->dev_addr, addr, AX25_ADDR_LEN))
		return -EFAULT;
	return 0;
}

static int ax_set_dev_mac_address(struct device *dev, void *addr)
{
	struct sockaddr *sa = addr;

	memcpy(dev->dev_addr, sa->sa_data, AX25_ADDR_LEN);

	return 0;
}


/* Perform I/O control on an active ax25 channel. */
static int ax25_disp_ioctl(struct tty_struct *tty, void *file, int cmd, void *arg)
{
	struct ax_disp *ax = (struct ax_disp *)tty->disc_data;
	unsigned int tmp;

	/* First make sure we're connected. */
	if (ax == NULL || ax->magic != AX25_MAGIC)
		return -EINVAL;

	switch (cmd) {
	 	case SIOCGIFNAME:
			if (copy_to_user(arg, ax->dev->name, strlen(ax->dev->name) + 1))
				return -EFAULT;
			return 0;

		case SIOCGIFENCAP:
			put_user(4, (int *)arg);
			return 0;

		case SIOCSIFENCAP:
			get_user(tmp, (int *)arg);
	 		ax->mode = tmp;
			ax->dev->addr_len        = AX25_ADDR_LEN;	  /* sizeof an AX.25 addr */
			ax->dev->hard_header_len = AX25_KISS_HEADER_LEN + AX25_MAX_HEADER_LEN + 3;
			ax->dev->type            = ARPHRD_AX25;
			return 0;

		 case SIOCSIFHWADDR:
			return ax_set_mac_address(ax->dev, arg);

		default:
			return -ENOIOCTLCMD;
	}
}

static int ax_open_dev(struct device *dev)
{
	struct ax_disp *ax = (struct ax_disp*)dev->priv;

	if (ax->tty==NULL)
		return -ENODEV;

	return 0;
}

/* Initialize AX25 control device -- register AX25 line discipline */
__initfunc(int mkiss_init_ctrl_dev(void))
{
	int status;

	if (ax25_maxdev < 4) ax25_maxdev = 4; /* Sanity */

	if ((ax25_ctrls = kmalloc(sizeof(void*) * ax25_maxdev, GFP_KERNEL)) == NULL) {
		printk(KERN_ERR "mkiss: Can't allocate ax25_ctrls[] array !  No mkiss available\n");
		return -ENOMEM;
	}

	/* Clear the pointer array, we allocate devices when we need them */
	memset(ax25_ctrls, 0, sizeof(void*) * ax25_maxdev); /* Pointers */

	/* Fill in our line protocol discipline, and register it */
	memset(&ax_ldisc, 0, sizeof(ax_ldisc));
	ax_ldisc.magic  = TTY_LDISC_MAGIC;
	ax_ldisc.name   = "mkiss";
	ax_ldisc.flags  = 0;
	ax_ldisc.open   = ax25_open;
	ax_ldisc.close  = ax25_close;
	ax_ldisc.read   = NULL;
	ax_ldisc.write  = NULL;
	ax_ldisc.ioctl  = (int (*)(struct tty_struct *, struct file *, unsigned int, unsigned long))ax25_disp_ioctl;
	ax_ldisc.poll   = NULL;

	ax_ldisc.receive_buf  = ax25_receive_buf;
	ax_ldisc.receive_room = ax25_receive_room;
	ax_ldisc.write_wakeup = ax25_write_wakeup;

	if ((status = tty_register_ldisc(N_AX25, &ax_ldisc)) != 0)
		printk(KERN_ERR "mkiss: can't register line discipline (err = %d)\n", status);

	mkiss_init();

#ifdef MODULE
	return status;
#else
	/*
	 * Return "not found", so that dev_init() will unlink
	 * the placeholder device entry for us.
	 */
	return ENODEV;
#endif
}


/* Initialize the driver.  Called by network startup. */

static int ax25_init(struct device *dev)
{
	struct ax_disp *ax = (struct ax_disp*)dev->priv;

	static char ax25_bcast[AX25_ADDR_LEN] =
		{'Q'<<1,'S'<<1,'T'<<1,' '<<1,' '<<1,' '<<1,'0'<<1};
	static char ax25_test[AX25_ADDR_LEN] =
		{'L'<<1,'I'<<1,'N'<<1,'U'<<1,'X'<<1,' '<<1,'1'<<1};

	if (ax == NULL)		/* Allocation failed ?? */
		return -ENODEV;

	/* Set up the "AX25 Control Block". (And clear statistics) */
	memset(ax, 0, sizeof (struct ax_disp));
	ax->magic  = AX25_MAGIC;
	ax->dev	   = dev;

	/* Finish setting up the DEVICE info. */
	dev->mtu             = AX_MTU;
	dev->hard_start_xmit = ax_xmit;
	dev->open            = ax_open_dev;
	dev->stop            = ax_close;
	dev->get_stats	     = ax_get_stats;
#ifdef HAVE_SET_MAC_ADDR
	dev->set_mac_address = ax_set_dev_mac_address;
#endif
	dev->hard_header_len = 0;
	dev->addr_len        = 0;
	dev->type            = ARPHRD_AX25;
	dev->tx_queue_len    = 10;

	memcpy(dev->broadcast, ax25_bcast, AX25_ADDR_LEN);
	memcpy(dev->dev_addr,  ax25_test,  AX25_ADDR_LEN);

#if defined(CONFIG_AX25) || defined(CONFIG_AX25_MODULE)
	dev->hard_header     = ax_header;
	dev->rebuild_header  = ax_rebuild_header;
#endif

	dev_init_buffers(dev);

	/* New-style flags. */
	dev->flags      = 0;

	return 0;
}

static int mkiss_open(struct tty_struct *tty, struct file *filp)
{
	struct mkiss_channel *mkiss;
	int chan;

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

	if (chan < 0 || chan >= NR_MKISS)
		return -ENODEV;

	mkiss = &MKISS_Info[chan];

	mkiss->magic =  MKISS_DRIVER_MAGIC;
	mkiss->init  = 1;
	mkiss->tty   = tty;

	tty->driver_data = mkiss;

	tty->termios->c_iflag  = IGNBRK | IGNPAR;
	tty->termios->c_cflag  = B9600 | CS8 | CLOCAL;
	tty->termios->c_cflag &= ~CBAUD;

	return 0;
}

static void mkiss_close(struct tty_struct *tty, struct file * filp)
{
	struct mkiss_channel *mkiss = tty->driver_data;

	if (mkiss == NULL || mkiss->magic != MKISS_DRIVER_MAGIC)
                return;

	mkiss->tty   = NULL;
	mkiss->init  = 0;
	tty->stopped = 0;
}

static int mkiss_write(struct tty_struct *tty, int from_user, const unsigned char *buf, int count)
{
	return 0;
}

static int mkiss_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg)
{
	/* Ignore serial ioctl's */
	switch (cmd) {
		case TCSBRK:
		case TIOCMGET:
		case TIOCMBIS:
		case TIOCMBIC:
		case TIOCMSET:
		case TCSETS:
		case TCSETSF:		/* should flush first, but... */
		case TCSETSW:		/* should wait until flush, but... */
			return 0;
		default:
			return -ENOIOCTLCMD;
	}
}


static void mkiss_dummy(struct tty_struct *tty)
{
	struct mkiss_channel *mkiss = tty->driver_data;

	if (tty == NULL)
		return;

	if (mkiss == NULL)
		return;
}

static void mkiss_dummy2(struct tty_struct *tty, unsigned char ch)
{
	struct mkiss_channel *mkiss = tty->driver_data;

	if (tty == NULL)
		return;

	if (mkiss == NULL)
		return;
}


static int mkiss_write_room(struct tty_struct * tty)
{
	struct mkiss_channel *mkiss = tty->driver_data;

	if (tty == NULL)
		return 0;

	if (mkiss == NULL)
		return 0;

	return 65536;  /* We can handle an infinite amount of data. :-) */
}


static int mkiss_chars_in_buffer(struct tty_struct *tty)
{
	struct mkiss_channel *mkiss = tty->driver_data;

	if (tty == NULL)
		return 0;

	if (mkiss == NULL)
		return 0;

	return 0;
}


static void mkiss_set_termios(struct tty_struct *tty, struct termios *old_termios)
{
	/* we don't do termios */
}

/* ******************************************************************** */
/* * 			Init MKISS driver 			      * */
/* ******************************************************************** */

__initfunc(static int mkiss_init(void))
{
	memset(&mkiss_driver, 0, sizeof(struct tty_driver));

	mkiss_driver.magic       = MKISS_DRIVER_MAGIC;
	mkiss_driver.name        = "mkiss";
	mkiss_driver.major       = MKISS_MAJOR;
	mkiss_driver.minor_start = 0;
	mkiss_driver.num         = NR_MKISS;
	mkiss_driver.type        = TTY_DRIVER_TYPE_SERIAL;
	mkiss_driver.subtype     = MKISS_SERIAL_TYPE_NORMAL;	/* not needed */

	mkiss_driver.init_termios         = tty_std_termios;
	mkiss_driver.init_termios.c_iflag = IGNBRK | IGNPAR;
	mkiss_driver.init_termios.c_cflag = B9600 | CS8 | CLOCAL;

	mkiss_driver.flags           = TTY_DRIVER_REAL_RAW;
	mkiss_driver.refcount        = &mkiss_refcount;
	mkiss_driver.table           = mkiss_table;
	mkiss_driver.termios         = (struct termios **)mkiss_termios;
	mkiss_driver.termios_locked  = (struct termios **)mkiss_termios_locked;

	mkiss_driver.ioctl           = mkiss_ioctl;
	mkiss_driver.open            = mkiss_open;
	mkiss_driver.close           = mkiss_close;
	mkiss_driver.write           = mkiss_write;
	mkiss_driver.write_room      = mkiss_write_room;
	mkiss_driver.chars_in_buffer = mkiss_chars_in_buffer;
	mkiss_driver.set_termios     = mkiss_set_termios;

	/* some unused functions */
	mkiss_driver.flush_buffer = mkiss_dummy;
	mkiss_driver.throttle     = mkiss_dummy;
	mkiss_driver.unthrottle   = mkiss_dummy;
	mkiss_driver.stop         = mkiss_dummy;
	mkiss_driver.start        = mkiss_dummy;
	mkiss_driver.hangup       = mkiss_dummy;
	mkiss_driver.flush_chars  = mkiss_dummy;
	mkiss_driver.put_char     = mkiss_dummy2;

	if (tty_register_driver(&mkiss_driver)) {
		printk(KERN_ERR "mkiss: couldn't register Mkiss device\n");
		return -EIO;
	}

	printk(KERN_INFO "AX.25 Multikiss device enabled\n");

	return 0;
}

#ifdef MODULE
EXPORT_NO_SYMBOLS;

MODULE_PARM(ax25_maxdev, "i");
MODULE_PARM_DESC(ax25_maxdev, "number of MKISS devices");

MODULE_AUTHOR("Hans Albas PE1AYX <[e-mail]>");
MODULE_DESCRIPTION("KISS driver for AX.25 over TTYs");

int init_module(void)
{
	return mkiss_init_ctrl_dev();
}

void cleanup_module(void)
{
	int i;

	if (ax25_ctrls != NULL) {
		for (i = 0; i < ax25_maxdev; i++) {
			if (ax25_ctrls[i]) {
				/*
				 * VSV = if dev->start==0, then device
				 * unregistred while close proc.
				 */
				if (ax25_ctrls[i]->dev.start)
					unregister_netdev(&(ax25_ctrls[i]->dev));

				kfree(ax25_ctrls[i]);
				ax25_ctrls[i] = NULL;
			}
		}

		kfree(ax25_ctrls);
		ax25_ctrls = NULL;
	}

	if ((i = tty_register_ldisc(N_AX25, NULL)))
		printk(KERN_ERR "mkiss: can't unregister line discipline (err = %d)\n", i);

	if (tty_unregister_driver(&mkiss_driver))	/* remove devive */
		printk(KERN_ERR "mkiss: can't unregister MKISS device\n");
}

#endif /* MODULE */