hdlcdrv.c

linux-2.4.29操作系统的源码

		return;
	}
	if ((--s->hdlctx.slotcnt) > 0)
		return;
	s->hdlctx.slotcnt = s->ch_params.slottime;
	if ((random_num() % 256) > s->ch_params.ppersist)
		return;
	start_tx(dev, s);
}

/* --------------------------------------------------------------------- */
/*
 * ===================== network driver interface =========================
 */

static inline int hdlcdrv_paranoia_check(struct net_device *dev,
					const char *routine)
{
	if (!dev || !dev->priv || 
	    ((struct hdlcdrv_state *)dev->priv)->magic != HDLCDRV_MAGIC) {
		printk(KERN_ERR "hdlcdrv: bad magic number for hdlcdrv_state "
		       "struct in routine %s\n", routine);
		return 1;
	}
	return 0;
}

/* --------------------------------------------------------------------- */

static int hdlcdrv_send_packet(struct sk_buff *skb, struct net_device *dev)
{
	struct hdlcdrv_state *sm;

	if (hdlcdrv_paranoia_check(dev, "hdlcdrv_send_packet"))
		return 0;
	sm = (struct hdlcdrv_state *)dev->priv;
	if (skb->data[0] != 0) {
		do_kiss_params(sm, skb->data, skb->len);
		dev_kfree_skb(skb);
		return 0;
	}
	if (sm->skb)
		return -1;
	netif_stop_queue(dev);
	sm->skb = skb;
	return 0;
}

/* --------------------------------------------------------------------- */

static int hdlcdrv_set_mac_address(struct net_device *dev, void *addr)
{
	struct sockaddr *sa = (struct sockaddr *)addr;

	/* addr is an AX.25 shifted ASCII mac address */
	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len); 
	return 0;                                         
}

/* --------------------------------------------------------------------- */

static struct net_device_stats *hdlcdrv_get_stats(struct net_device *dev)
{
	struct hdlcdrv_state *sm;

	if (hdlcdrv_paranoia_check(dev, "hdlcdrv_get_stats"))
		return NULL;
	sm = (struct hdlcdrv_state *)dev->priv;
	/* 
	 * Get the current statistics.  This may be called with the
	 * card open or closed. 
	 */
	return &sm->stats;
}

/* --------------------------------------------------------------------- */
/*
 * Open/initialize the board. This is called (in the current kernel)
 * sometime after booting when the 'ifconfig' program is run.
 *
 * This routine should set everything up anew at each open, even
 * registers that "should" only need to be set once at boot, so that
 * there is non-reboot way to recover if something goes wrong.
 */

static int hdlcdrv_open(struct net_device *dev)
{
	struct hdlcdrv_state *s;
	int i;

	if (hdlcdrv_paranoia_check(dev, "hdlcdrv_open"))
		return -EINVAL;
	s = (struct hdlcdrv_state *)dev->priv;

	if (!s->ops || !s->ops->open)
		return -ENODEV;

	/*
	 * initialise some variables
	 */
	s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
	s->hdlcrx.in_hdlc_rx = 0;
	s->hdlcrx.rx_state = 0;
	
	s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
	s->hdlctx.in_hdlc_tx = 0;
	s->hdlctx.tx_state = 1;
	s->hdlctx.numflags = 0;
	s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
	s->hdlctx.ptt = 0;
	s->hdlctx.slotcnt = s->ch_params.slottime;
	s->hdlctx.calibrate = 0;

	i = s->ops->open(dev);
	if (i)
		return i;
	netif_start_queue(dev);
	return 0;
}

/* --------------------------------------------------------------------- */
/* 
 * The inverse routine to hdlcdrv_open(). 
 */

static int hdlcdrv_close(struct net_device *dev)
{
	struct hdlcdrv_state *s;
	int i = 0;

	if (hdlcdrv_paranoia_check(dev, "hdlcdrv_close"))
		return -EINVAL;
	s = (struct hdlcdrv_state *)dev->priv;

	if (s->ops && s->ops->close)
		i = s->ops->close(dev);
	if (s->skb)
		dev_kfree_skb(s->skb);
	s->skb = NULL;
	return i;
}

/* --------------------------------------------------------------------- */

static int hdlcdrv_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
	struct hdlcdrv_state *s;
	struct hdlcdrv_ioctl bi;
		
	if (hdlcdrv_paranoia_check(dev, "hdlcdrv_ioctl"))
		return -EINVAL;
	s = (struct hdlcdrv_state *)dev->priv;

	if (cmd != SIOCDEVPRIVATE) {
		if (s->ops && s->ops->ioctl)
			return s->ops->ioctl(dev, ifr, &bi, cmd);
		return -ENOIOCTLCMD;
	}
	if (copy_from_user(&bi, ifr->ifr_data, sizeof(bi)))
		return -EFAULT;

	switch (bi.cmd) {
	default:
		if (s->ops && s->ops->ioctl)
			return s->ops->ioctl(dev, ifr, &bi, cmd);
		return -ENOIOCTLCMD;

	case HDLCDRVCTL_GETCHANNELPAR:
		bi.data.cp.tx_delay = s->ch_params.tx_delay;
		bi.data.cp.tx_tail = s->ch_params.tx_tail;
		bi.data.cp.slottime = s->ch_params.slottime;
		bi.data.cp.ppersist = s->ch_params.ppersist;
		bi.data.cp.fulldup = s->ch_params.fulldup;
		break;

	case HDLCDRVCTL_SETCHANNELPAR:
		if (!capable(CAP_NET_ADMIN))
			return -EACCES;
		s->ch_params.tx_delay = bi.data.cp.tx_delay;
		s->ch_params.tx_tail = bi.data.cp.tx_tail;
		s->ch_params.slottime = bi.data.cp.slottime;
		s->ch_params.ppersist = bi.data.cp.ppersist;
		s->ch_params.fulldup = bi.data.cp.fulldup;
		s->hdlctx.slotcnt = 1;
		return 0;
		
	case HDLCDRVCTL_GETMODEMPAR:
		bi.data.mp.iobase = dev->base_addr;
		bi.data.mp.irq = dev->irq;
		bi.data.mp.dma = dev->dma;
		bi.data.mp.dma2 = s->ptt_out.dma2;
		bi.data.mp.seriobase = s->ptt_out.seriobase;
		bi.data.mp.pariobase = s->ptt_out.pariobase;
		bi.data.mp.midiiobase = s->ptt_out.midiiobase;
		break;

	case HDLCDRVCTL_SETMODEMPAR:
		if ((!capable(CAP_SYS_RAWIO)) || netif_running(dev))
			return -EACCES;
		dev->base_addr = bi.data.mp.iobase;
		dev->irq = bi.data.mp.irq;
		dev->dma = bi.data.mp.dma;
		s->ptt_out.dma2 = bi.data.mp.dma2;
		s->ptt_out.seriobase = bi.data.mp.seriobase;
		s->ptt_out.pariobase = bi.data.mp.pariobase;
		s->ptt_out.midiiobase = bi.data.mp.midiiobase;
		return 0;	
	
	case HDLCDRVCTL_GETSTAT:
		bi.data.cs.ptt = hdlcdrv_ptt(s);
		bi.data.cs.dcd = s->hdlcrx.dcd;
		bi.data.cs.ptt_keyed = s->ptt_keyed;
		bi.data.cs.tx_packets = s->stats.tx_packets;
		bi.data.cs.tx_errors = s->stats.tx_errors;
		bi.data.cs.rx_packets = s->stats.rx_packets;
		bi.data.cs.rx_errors = s->stats.rx_errors;
		break;		

	case HDLCDRVCTL_OLDGETSTAT:
		bi.data.ocs.ptt = hdlcdrv_ptt(s);
		bi.data.ocs.dcd = s->hdlcrx.dcd;
		bi.data.ocs.ptt_keyed = s->ptt_keyed;
		break;		

	case HDLCDRVCTL_CALIBRATE:
		if(!capable(CAP_SYS_RAWIO))
			return -EPERM;
		s->hdlctx.calibrate = bi.data.calibrate * s->par.bitrate / 16;
		return 0;

	case HDLCDRVCTL_GETSAMPLES:
#ifndef HDLCDRV_DEBUG
		return -EPERM;
#else /* HDLCDRV_DEBUG */
		if (s->bitbuf_channel.rd == s->bitbuf_channel.wr) 
			return -EAGAIN;
		bi.data.bits = 
			s->bitbuf_channel.buffer[s->bitbuf_channel.rd];
		s->bitbuf_channel.rd = (s->bitbuf_channel.rd+1) %
			sizeof(s->bitbuf_channel.buffer);
		break;
#endif /* HDLCDRV_DEBUG */
				
	case HDLCDRVCTL_GETBITS:
#ifndef HDLCDRV_DEBUG
		return -EPERM;
#else /* HDLCDRV_DEBUG */
		if (s->bitbuf_hdlc.rd == s->bitbuf_hdlc.wr) 
			return -EAGAIN;
		bi.data.bits = 
			s->bitbuf_hdlc.buffer[s->bitbuf_hdlc.rd];
		s->bitbuf_hdlc.rd = (s->bitbuf_hdlc.rd+1) %
			sizeof(s->bitbuf_hdlc.buffer);
		break;		
#endif /* HDLCDRV_DEBUG */

	case HDLCDRVCTL_DRIVERNAME:
		if (s->ops && s->ops->drvname) {
			strncpy(bi.data.drivername, s->ops->drvname, 
				sizeof(bi.data.drivername));
			break;
		}
		bi.data.drivername[0] = '\0';
		break;
		
	}
	if (copy_to_user(ifr->ifr_data, &bi, sizeof(bi)))
		return -EFAULT;
	return 0;

}

/* --------------------------------------------------------------------- */

/*
 * Check for a network adaptor of this type, and return '0' if one exists.
 * If dev->base_addr == 0, probe all likely locations.
 * If dev->base_addr == 1, always return failure.
 * If dev->base_addr == 2, allocate space for the device and return success
 * (detachable devices only).
 */
static int hdlcdrv_probe(struct net_device *dev)
{
	const struct hdlcdrv_channel_params dflt_ch_params = { 
		20, 2, 10, 40, 0 
	};
	struct hdlcdrv_state *s;

	if (!dev)
		return -ENXIO;
	/*
	 * not a real probe! only initialize data structures
	 */
	s = (struct hdlcdrv_state *)dev->priv;
	/*
	 * initialize the hdlcdrv_state struct
	 */
	s->ch_params = dflt_ch_params;
	s->ptt_keyed = 0;

	spin_lock_init(&s->hdlcrx.hbuf.lock);
	s->hdlcrx.hbuf.rd = s->hdlcrx.hbuf.wr = 0;
	s->hdlcrx.in_hdlc_rx = 0;
	s->hdlcrx.rx_state = 0;
	
	spin_lock_init(&s->hdlctx.hbuf.lock);
	s->hdlctx.hbuf.rd = s->hdlctx.hbuf.wr = 0;
	s->hdlctx.in_hdlc_tx = 0;
	s->hdlctx.tx_state = 1;
	s->hdlctx.numflags = 0;
	s->hdlctx.bitstream = s->hdlctx.bitbuf = s->hdlctx.numbits = 0;
	s->hdlctx.ptt = 0;
	s->hdlctx.slotcnt = s->ch_params.slottime;
	s->hdlctx.calibrate = 0;

#ifdef HDLCDRV_DEBUG
	s->bitbuf_channel.rd = s->bitbuf_channel.wr = 0;
	s->bitbuf_channel.shreg = 0x80;

	s->bitbuf_hdlc.rd = s->bitbuf_hdlc.wr = 0;
	s->bitbuf_hdlc.shreg = 0x80;
#endif /* HDLCDRV_DEBUG */

	/*
	 * initialize the device struct
	 */
	dev->open = hdlcdrv_open;
	dev->stop = hdlcdrv_close;
	dev->do_ioctl = hdlcdrv_ioctl;
	dev->hard_start_xmit = hdlcdrv_send_packet;
	dev->get_stats = hdlcdrv_get_stats;

	/* Fill in the fields of the device structure */

	s->skb = NULL;
	
#if defined(CONFIG_AX25) || defined(CONFIG_AX25_MODULE)
	dev->hard_header = ax25_encapsulate;
	dev->rebuild_header = ax25_rebuild_header;
#else /* CONFIG_AX25 || CONFIG_AX25_MODULE */
	dev->hard_header = NULL;
	dev->rebuild_header = NULL;
#endif /* CONFIG_AX25 || CONFIG_AX25_MODULE */
	dev->set_mac_address = hdlcdrv_set_mac_address;
	
	dev->type = ARPHRD_AX25;           /* AF_AX25 device */
	dev->hard_header_len = AX25_MAX_HEADER_LEN + AX25_BPQ_HEADER_LEN;
	dev->mtu = AX25_DEF_PACLEN;        /* eth_mtu is the default */
	dev->addr_len = AX25_ADDR_LEN;     /* sizeof an ax.25 address */
	memcpy(dev->broadcast, ax25_bcast, AX25_ADDR_LEN);
	memcpy(dev->dev_addr, ax25_nocall, AX25_ADDR_LEN);
	dev->tx_queue_len = 16;

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

	return 0;
}

/* --------------------------------------------------------------------- */

int hdlcdrv_register_hdlcdrv(struct net_device *dev, const struct hdlcdrv_ops *ops,
			     unsigned int privsize, char *ifname,
			     unsigned int baseaddr, unsigned int irq, 
			     unsigned int dma) 
{
	struct hdlcdrv_state *s;

	if (!dev || !ops)
		return -EACCES;
	if (privsize < sizeof(struct hdlcdrv_state))
		privsize = sizeof(struct hdlcdrv_state);
	memset(dev, 0, sizeof(struct net_device));
	if (!(s = dev->priv = kmalloc(privsize, GFP_KERNEL)))
		return -ENOMEM;
	/*
	 * initialize part of the hdlcdrv_state struct
	 */
	memset(s, 0, privsize);
	s->magic = HDLCDRV_MAGIC;
	strncpy(dev->name, ifname, sizeof(dev->name));
	s->ops = ops;
	/*
	 * initialize part of the device struct
	 */
	dev->if_port = 0;
	dev->init = hdlcdrv_probe;
	dev->base_addr = baseaddr;
	dev->irq = irq;
	dev->dma = dma;
	if (register_netdev(dev)) {
		printk(KERN_WARNING "hdlcdrv: cannot register net "
		       "device %s\n", dev->name);
		kfree(dev->priv);
		return -ENXIO;
	}
	MOD_INC_USE_COUNT;
	return 0;
}

/* --------------------------------------------------------------------- */

int hdlcdrv_unregister_hdlcdrv(struct net_device *dev) 
{
	struct hdlcdrv_state *s;

	if (!dev)
		return -EINVAL;
	if (!(s = (struct hdlcdrv_state *)dev->priv))
		return -EINVAL;
	if (s->magic != HDLCDRV_MAGIC)
		return -EINVAL;
	if (s->ops->close)
		s->ops->close(dev);
	unregister_netdev(dev);
	kfree(s);
	MOD_DEC_USE_COUNT;
	return 0;
}

/* --------------------------------------------------------------------- */

EXPORT_SYMBOL(hdlcdrv_receiver);
EXPORT_SYMBOL(hdlcdrv_transmitter);
EXPORT_SYMBOL(hdlcdrv_arbitrate);
EXPORT_SYMBOL(hdlcdrv_register_hdlcdrv);
EXPORT_SYMBOL(hdlcdrv_unregister_hdlcdrv);

/* --------------------------------------------------------------------- */

static int __init hdlcdrv_init_driver(void)
{
	printk(KERN_INFO "hdlcdrv: (C) 1996-2000 Thomas Sailer HB9JNX/AE4WA\n");
	printk(KERN_INFO "hdlcdrv: version 0.8 compiled " __TIME__ " " __DATE__ "\n");
	return 0;
}

/* --------------------------------------------------------------------- */

static void __exit hdlcdrv_cleanup_driver(void)
{
	printk(KERN_INFO "hdlcdrv: cleanup\n");
}

/* --------------------------------------------------------------------- */

MODULE_AUTHOR("Thomas M. Sailer, [e-mail], [e-mail]");
MODULE_DESCRIPTION("Packet Radio network interface HDLC encoder/decoder");
MODULE_LICENSE("GPL");
module_init(hdlcdrv_init_driver);
module_exit(hdlcdrv_cleanup_driver);

/* --------------------------------------------------------------------- */