patch-2.1.25 linux/drivers/net/sdla_fr.c

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diff -u --recursive --new-file v2.1.24/linux/drivers/net/sdla_fr.c linux/drivers/net/sdla_fr.c
@@ -0,0 +1,1428 @@
+/*****************************************************************************
+* sdla_fr.c	WANPIPE(tm) Multiprotocol WAN Link Driver. Frame relay module.
+*
+* Author:	Gene Kozin	<genek@compuserve.com>
+*
+* Copyright:	(c) 1995-1997 Sangoma Technologies Inc.
+*
+*		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.
+* ============================================================================
+* Jan 02, 1997	Gene Kozin	Initial version.
+*****************************************************************************/
+
+#if	!defined(__KERNEL__) || !defined(MODULE)
+#error	This code MUST be compiled as a kernel module!
+#endif
+
+#include <linux/kernel.h>	/* printk(), and other useful stuff */
+#include <linux/stddef.h>	/* offsetof(), etc. */
+#include <linux/errno.h>	/* return codes */
+#include <linux/string.h>	/* inline memset(), etc. */
+#include <linux/malloc.h>	/* kmalloc(), kfree() */
+#include <linux/router.h>	/* WAN router definitions */
+#include <linux/wanpipe.h>	/* WANPIPE common user API definitions */
+#include <linux/if_arp.h>	/* ARPHRD_* defines */
+#include <asm/byteorder.h>	/* htons(), etc. */
+#include <asm/io.h>		/* for inb(), outb(), etc. */
+
+#define	_GNUC_
+#include <linux/sdla_fr.h>	/* frame relay firmware API definitions */
+
+/****** Defines & Macros ****************************************************/
+
+#define	CMD_OK		0		/* normal firmware return code */
+#define	CMD_TIMEOUT	0xFF		/* firmware command timed out */
+#define	MAX_CMD_RETRY	10		/* max number of firmware retries */
+
+#define	FR_HEADER_LEN	8		/* max encapsulation header size */
+#define	FR_CHANNEL_MTU	1500		/* unfragmented logical channel MTU */
+
+/* Q.922 frame types */
+#define	Q922_UI		0x03		/* Unnumbered Info frame */
+#define	Q922_XID	0xAF		/* ??? */
+
+/****** Data Structures *****************************************************/
+
+/* This is an extention of the 'struct device' we create for each network
+ * interface to keep the rest of channel-specific data.
+ */
+typedef struct fr_channel
+{
+	char name[WAN_IFNAME_SZ+1];	/* interface name, ASCIIZ */
+	unsigned dlci;			/* logical channel number */
+	unsigned cir;			/* committed information rate */
+	char state;			/* channel state */
+	unsigned long state_tick;	/* time of the last state change */
+	sdla_t* card;			/* -> owner */
+	struct enet_statistics ifstats;	/* interface statistics */
+} fr_channel_t;
+
+typedef struct dlci_status
+{
+	unsigned short dlci	PACKED;
+	unsigned char state	PACKED;
+} dlci_status_t;
+
+/****** Function Prototypes *************************************************/
+
+/* WAN link driver entry points. These are called by the WAN router module. */
+static int update (wan_device_t* wandev);
+static int new_if (wan_device_t* wandev, struct device* dev,
+	wanif_conf_t* conf);
+static int del_if (wan_device_t* wandev, struct device* dev);
+
+/* Network device interface */
+static int if_init   (struct device* dev);
+static int if_open   (struct device* dev);
+static int if_close  (struct device* dev);
+static int if_header (struct sk_buff* skb, struct device* dev,
+	unsigned short type, void* daddr, void* saddr, unsigned len);
+static int if_rebuild_hdr (void* hdr, struct device* dev, unsigned long raddr,
+	struct sk_buff* skb);
+static int if_send (struct sk_buff* skb, struct device* dev);
+static struct enet_statistics* if_stats (struct device* dev);
+
+/* Interrupt handlers */
+static void fr502_isr (sdla_t* card);
+static void fr508_isr (sdla_t* card);
+static void fr502_rx_intr (sdla_t* card);
+static void fr508_rx_intr (sdla_t* card);
+static void tx_intr (sdla_t* card);
+static void spur_intr (sdla_t* card);
+
+/* Background polling routines */
+static void wpf_poll (sdla_t* card);
+
+/* Frame relay firmware interface functions */
+static int fr_read_version (sdla_t* card, char* str);
+static int fr_configure (sdla_t* card, fr_conf_t *conf);
+static int fr_set_intr_mode (sdla_t* card, unsigned mode, unsigned mtu);
+static int fr_comm_enable (sdla_t* card);
+static int fr_comm_disable (sdla_t* card);
+static int fr_add_dlci (sdla_t* card, int dlci, int num);
+static int fr_activate_dlci (sdla_t* card, int dlci, int num);
+static int fr_issue_isf (sdla_t* card, int isf);
+static int fr502_send (sdla_t* card, int dlci, int attr, int len, void *buf);
+static int fr508_send (sdla_t* card, int dlci, int attr, int len, void *buf);
+
+/* Firmware asynchronous event handlers */
+static int fr_event (sdla_t* card, int event, fr_mbox_t* mbox);
+static int fr_modem_failure (sdla_t *card, fr_mbox_t* mbox);
+static int fr_dlci_change (sdla_t *card, fr_mbox_t* mbox);
+
+/* Miscellaneous functions */
+static int update_chan_state (struct device* dev);
+static void set_chan_state (struct device* dev, int state);
+static struct device* find_channel (sdla_t* card, unsigned dlci);
+static int is_tx_ready (sdla_t* card);
+static unsigned int dec_to_uint (unsigned char* str, int len);
+static unsigned int hex_to_uint (unsigned char* str, int len);
+
+/****** Public Functions ****************************************************/
+
+/*============================================================================
+ * Frame relay protocol initialization routine.
+ *
+ * This routine is called by the main WANPIPE module during setup.  At this
+ * point adapter is completely initialized and firmware is running.
+ *  o read firmware version (to make sure it's alive)
+ *  o configure adapter
+ *  o initialize protocol-specific fields of the adapter data space.
+ *
+ * Return:	0	o.k.
+ *		< 0	failure.
+ */
+int wpf_init (sdla_t* card, wandev_conf_t* conf)
+{
+	union
+	{
+		char str[80];
+		fr_conf_t cfg;
+	} u;
+
+	/* Verify configuration ID */
+	if (conf->config_id != WANCONFIG_FR)
+	{
+		printk(KERN_INFO "%s: invalid configuration ID %u!\n",
+			card->devname, conf->config_id)
+		;
+		return -EINVAL;
+	}
+
+	/* Initialize protocol-specific fields of adapter data space */
+	switch (card->hw.fwid)
+	{
+	case SFID_FR502:
+		card->mbox  = (void*)(card->hw.dpmbase + FR502_MBOX_OFFS);
+		card->rxmb  = (void*)(card->hw.dpmbase + FR502_RXMB_OFFS);
+		card->flags = (void*)(card->hw.dpmbase + FR502_FLAG_OFFS);
+		card->isr = &fr502_isr;
+		break;
+
+	case SFID_FR508:
+		card->mbox  = (void*)(card->hw.dpmbase + FR508_MBOX_OFFS);
+		card->flags = (void*)(card->hw.dpmbase + FR508_FLAG_OFFS);
+		card->isr = &fr508_isr;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	/* Read firmware version.  Note that when adapter initializes, it
+	 * clears the mailbox, so it may appear that the first command was
+	 * executed successfully when in fact it was merely erased. To work
+	 * around this, we execute the first command twice.
+	 */
+	if (fr_read_version(card, NULL) || fr_read_version(card, u.str))
+		return -EIO
+	;
+	printk(KERN_INFO "%s: running frame relay firmware v%s\n",
+		card->devname, u.str)
+	;
+
+	/* Adjust configuration */
+	conf->mtu = max(min(conf->mtu, 4080), FR_CHANNEL_MTU + FR_HEADER_LEN);
+	conf->bps = min(conf->bps, 2048000);
+
+	/* Configure adapter firmware */
+	memset(&u.cfg, 0, sizeof(u.cfg));
+	u.cfg.mtu	= conf->mtu;
+	u.cfg.t391	= 10;
+	u.cfg.t392	= 15;
+	u.cfg.n391	= 6;
+	u.cfg.n392	= 3;
+	u.cfg.n393	= 4;
+	u.cfg.kbps	= conf->bps / 1000;
+	u.cfg.cir_fwd	= max(min(u.cfg.kbps, 512), 1);
+	u.cfg.cir_bwd = u.cfg.bc_fwd = u.cfg.bc_bwd = u.cfg.cir_fwd;
+	u.cfg.options	= 0x0081;	/* direct Rx, no CIR check */
+	switch (conf->u.fr.signalling)
+	{
+	case WANOPT_FR_Q933:	u.cfg.options |= 0x0200; break;
+	case WANOPT_FR_LMI:	u.cfg.options |= 0x0400; break;
+	}
+	if (conf->station == WANOPT_CPE)
+	{
+		u.cfg.options |= 0x8000;	/* auto config DLCI */
+	}
+	else
+	{
+		u.cfg.station = 1;	/* switch emulation mode */
+		card->u.f.node_dlci = conf->u.fr.dlci ? conf->u.fr.dlci : 16;
+		card->u.f.dlci_num  = max(min(conf->u.fr.dlci_num, 1), 100);
+	}
+	if (conf->clocking == WANOPT_INTERNAL)
+		u.cfg.port |= 0x0001
+	;
+	if (conf->interface == WANOPT_RS232)
+		u.cfg.port |= 0x0002
+	;
+	if (conf->u.fr.t391)
+		u.cfg.t391 = min(conf->u.fr.t391, 30)
+	;
+	if (conf->u.fr.t392)
+		u.cfg.t392 = min(conf->u.fr.t392, 30)
+	;
+	if (conf->u.fr.n391)
+		u.cfg.n391 = min(conf->u.fr.n391, 255)
+	;
+	if (conf->u.fr.n392)
+		u.cfg.n392 = min(conf->u.fr.n392, 10)
+	;
+	if (conf->u.fr.n393)
+		u.cfg.n393 = min(conf->u.fr.n393, 10)
+	;
+
+	if (fr_configure(card, &u.cfg))
+		return -EIO
+	;
+
+	if (card->hw.fwid == SFID_FR508)
+	{
+		fr_buf_info_t* buf_info =
+			(void*)(card->hw.dpmbase + FR508_RXBC_OFFS)
+		;
+
+		card->rxmb =
+			(void*)(buf_info->rse_next -
+			FR_MB_VECTOR + card->hw.dpmbase)
+		;
+		card->u.f.rxmb_base =
+			(void*)(buf_info->rse_base -
+			FR_MB_VECTOR + card->hw.dpmbase)
+		;
+		card->u.f.rxmb_last =
+			(void*)(buf_info->rse_base +
+			(buf_info->rse_num - 1) * sizeof(fr_buf_ctl_t) -
+			FR_MB_VECTOR + card->hw.dpmbase)
+		;
+		card->u.f.rx_base = buf_info->buf_base;
+		card->u.f.rx_top  = buf_info->buf_top;
+	}
+	card->wandev.mtu	= conf->mtu;
+	card->wandev.bps	= conf->bps;
+	card->wandev.interface	= conf->interface;
+	card->wandev.clocking	= conf->clocking;
+	card->wandev.station	= conf->station;
+	card->poll		= &wpf_poll;
+	card->wandev.update	= &update;
+	card->wandev.new_if	= &new_if;
+	card->wandev.del_if	= &del_if;
+	card->wandev.state	= WAN_DISCONNECTED;
+	return 0;
+}
+
+/******* WAN Device Driver Entry Points *************************************/
+
+/*============================================================================
+ * Update device status & statistics.
+ */
+static int update (wan_device_t* wandev)
+{
+/*
+	sdla_t* card = wandev->private;
+*/
+	return 0;
+}
+
+/*============================================================================
+ * Create new logical channel.
+ * This routine is called by the router when ROUTER_IFNEW IOCTL is being
+ * handled.
+ * o parse media- and hardware-specific configuration
+ * o make sure that a new channel can be created
+ * o allocate resources, if necessary
+ * o prepare network device structure for registaration.
+ *
+ * Return:	0	o.k.
+ *		< 0	failure (channel will not be created)
+ */
+static int new_if (wan_device_t* wandev, struct device* dev, wanif_conf_t* conf)
+{
+	sdla_t* card = wandev->private;
+	fr_channel_t* chan;
+	int err = 0;
+
+	if ((conf->name[0] == '\0') || (strlen(conf->name) > WAN_IFNAME_SZ))
+	{
+		printk(KERN_INFO "%s: invalid interface name!\n",
+			card->devname)
+		;
+		return -EINVAL;
+	}
+
+	/* allocate and initialize private data */
+	chan = kmalloc(sizeof(fr_channel_t), GFP_KERNEL);
+	if (chan == NULL)
+		return -ENOMEM
+	;
+	memset(chan, 0, sizeof(fr_channel_t));
+	strcpy(chan->name, conf->name);
+	chan->card = card;
+
+	/* verify media address */
+	if (is_digit(conf->addr[0]))
+	{
+		int dlci = dec_to_uint(conf->addr, 0);
+
+		if (dlci && (dlci <= 4095))
+		{
+			chan->dlci = dlci;
+		}
+		else
+		{
+			printk(KERN_ERR
+				"%s: invalid DLCI %u on interface %s!\n",
+				wandev->name, dlci, chan->name)
+			;
+			err = -EINVAL;
+		}
+	}
+	else
+	{
+		printk(KERN_ERR
+			"%s: invalid media address on interface %s!\n",
+			wandev->name, chan->name)
+		;
+		err = -EINVAL;
+	}
+	if (err)
+	{
+		kfree(chan);
+		return err;
+	}
+
+	/* prepare network device data space for registration */
+	dev->name = chan->name;
+	dev->init = &if_init;
+	dev->priv = chan;
+	return 0;
+}
+
+/*============================================================================
+ * Delete logical channel.
+ */
+static int del_if (wan_device_t* wandev, struct device* dev)
+{
+	if (dev->priv)
+	{
+		kfree(dev->priv);
+		dev->priv = NULL;
+	}
+	return 0;
+}
+
+/****** Network Device Interface ********************************************/
+
+/*============================================================================
+ * Initialize Linux network interface.
+ *
+ * This routine is called only once for each interface, during Linux network
+ * interface registration.  Returning anything but zero will fail interface
+ * registration.
+ */
+static int if_init (struct device* dev)
+{
+	fr_channel_t* chan = dev->priv;
+	sdla_t* card = chan->card;
+	wan_device_t* wandev = &card->wandev;
+	int i;
+
+	/* Initialize device driver entry points */
+	dev->open		= &if_open;
+	dev->stop		= &if_close;
+	dev->hard_header	= &if_header;
+	dev->rebuild_header	= &if_rebuild_hdr;
+	dev->hard_start_xmit	= &if_send;
+	dev->get_stats		= &if_stats;
+
+	/* Initialize media-specific parameters */
+	dev->family		= AF_INET;	/* address family */
+	dev->type		= ARPHRD_DLCI;	/* ARP h/w type */
+	dev->mtu		= FR_CHANNEL_MTU;
+	dev->hard_header_len	= FR_HEADER_LEN;/* media header length */
+	dev->addr_len		= 2;		/* hardware address length */
+	*(unsigned short*)dev->dev_addr = htons(chan->dlci);
+
+	/* Initialize hardware parameters (just for reference) */
+	dev->irq	= wandev->irq;
+	dev->dma	= wandev->dma;
+	dev->base_addr	= wandev->ioport;
+	dev->mem_start	= wandev->maddr;
+	dev->mem_end	= wandev->maddr + wandev->msize - 1;
+
+	/* Initialize socket buffers */
+	for (i = 0; i < DEV_NUMBUFFS; ++i)
+		skb_queue_head_init(&dev->buffs[i])
+	;
+	set_chan_state(dev, WAN_DISCONNECTED);
+	return 0;
+}
+
+/*============================================================================
+ * Open network interface.
+ * o if this is the first open, then enable communications and interrupts.
+ * o prevent module from unloading by incrementing use count
+ *
+ * Return 0 if O.k. or errno.
+ */
+static int if_open (struct device* dev)
+{
+	fr_channel_t* chan = dev->priv;
+	sdla_t* card = chan->card;
+	int err = 0;
+
+	if (dev->start)
+		return -EBUSY		/* only one open is allowed */
+	;
+	if (set_bit(0, (void*)&card->wandev.critical))
+		return -EAGAIN;
+	;
+	if (!card->open_cnt)
+	{
+		if ((fr_comm_enable(card)) ||
+		    (fr_set_intr_mode(card, 0x03, card->wandev.mtu)))
+		{
+			err = -EIO;
+			goto done;
+		}
+		if (card->wandev.station == WANOPT_CPE)
+		{
+			/* CPE: issue full status enquiry */
+			fr_issue_isf(card, FR_ISF_FSE);
+		}
+		else	/* Switch: activate DLCI(s) */
+		{
+			fr_add_dlci(card,
+				card->u.f.node_dlci, card->u.f.dlci_num)
+			;
+			fr_activate_dlci(card,
+				card->u.f.node_dlci, card->u.f.dlci_num)
+			;
+		}
+		wanpipe_set_state(card, WAN_CONNECTED);
+	}
+	dev->mtu = min(dev->mtu, card->wandev.mtu - FR_HEADER_LEN);
+	dev->interrupt = 0;
+	dev->tbusy = 0;
+	dev->start = 1;
+	wanpipe_open(card);
+	update_chan_state(dev);
+
+done:
+	card->wandev.critical = 0;
+	return err;
+}
+
+/*============================================================================
+ * Close network interface.
+ * o if this is the last open, then disable communications and interrupts.
+ * o reset flags.
+ */
+static int if_close (struct device* dev)
+{
+	fr_channel_t* chan = dev->priv;
+	sdla_t* card = chan->card;
+
+	if (set_bit(0, (void*)&card->wandev.critical))
+		return -EAGAIN;
+	;
+	dev->start = 0;
+	wanpipe_close(card);
+	if (!card->open_cnt)
+	{
+		wanpipe_set_state(card, WAN_DISCONNECTED);
+		fr_set_intr_mode(card, 0, 0);
+		fr_comm_disable(card);
+	}
+	card->wandev.critical = 0;
+	return 0;
+}
+
+/*============================================================================
+ * Build media header.
+ * o encapsulate packet according to encapsulation type.
+ *
+ * The trick here is to put packet type (Ethertype) into 'protocol' field of
+ * the socket buffer, so that we don't forget it.  If encapsulation fails,
+ * set skb->protocol to 0 and discard packet later.
+ *
+ * Return:	media header length.
+ */
+static int if_header (struct sk_buff* skb, struct device* dev,
+	unsigned short type, void* daddr, void* saddr, unsigned len)
+{
+	int hdr_len = 0;
+
+	skb->protocol = type;
+	hdr_len = wan_encapsulate(skb, dev);
+	if (hdr_len < 0)
+	{
+		hdr_len = 0;
+		skb->protocol = 0;
+	}
+	skb_push(skb, 1);
+	skb->data[0] = Q922_UI;
+	++hdr_len;
+	return hdr_len;
+}
+
+/*============================================================================
+ * Re-build media header.
+ *
+ * Return:	1	physical address resolved.
+ *		0	physical address not resolved
+ */
+static int if_rebuild_hdr (void* hdr, struct device* dev, unsigned long raddr,
+			   struct sk_buff* skb)
+{
+	fr_channel_t* chan = dev->priv;
+	sdla_t* card = chan->card;
+
+	printk(KERN_INFO "%s: rebuild_header() called for interface %s!\n",
+		card->devname, dev->name)
+	;
+	return 1;
+}
+
+/*============================================================================
+ * Send a packet on a network interface.
+ * o set tbusy flag (marks start of the transmission) to block a timer-based
+ *   transmit from overlapping.
+ * o check link state. If link is not up, then drop the packet.
+ * o check channel status. If it's down then initiate a call.
+ * o pass a packet to corresponding WAN device.
+ * o free socket buffer
+ *
+ * Return:	0	complete (socket buffer must be freed)
+ *		non-0	packet may be re-transmitted (tbusy must be set)
+ *
+ * Notes:
+ * 1. This routine is called either by the protocol stack or by the "net
+ *    bottom half" (with interrupts enabled).
+ * 2. Setting tbusy flag will inhibit further transmit requests from the
+ *    protocol stack and can be used for flow control with protocol layer.
+ */
+static int if_send (struct sk_buff* skb, struct device* dev)
+{
+	fr_channel_t* chan = dev->priv;
+	sdla_t* card = chan->card;
+	int retry = 0;
+
+	if (skb == NULL)
+	{
+		/* If we get here, some higher layer thinks we've missed an
+		 * tx-done interrupt.
+		 */
+#ifdef _DEBUG_
+		printk(KERN_INFO "%s: interface %s got kicked!\n",
+			card->devname, dev->name)
+		;
+#endif
+		dev_tint(dev);
+		return 0;
+	}
+
+	if (set_bit(0, (void*)&card->wandev.critical))
+	{
+#ifdef _DEBUG_
+		printk(KERN_INFO "%s: if_send() hit critical section!\n",
+			card->devname)
+		;
+#endif
+		return 1;
+	}
+
+	if (set_bit(0, (void*)&dev->tbusy))
+	{
+#ifdef _DEBUG_
+		printk(KERN_INFO "%s: Tx collision on interface %s!\n",
+			card->devname, dev->name)
+		;
+#endif
+		++chan->ifstats.collisions;
+		retry = 1;
+	}
+	else if ((card->wandev.state != WAN_CONNECTED) ||
+	    (chan->state != WAN_CONNECTED))
+		++chan->ifstats.tx_dropped
+	;
+	else if (!is_tx_ready(card))
+		retry = 1
+	;
+	else
+	{
+ 		int err = (card->hw.fwid == SFID_FR508) ?
+			fr508_send(card, chan->dlci, 0, skb->len, skb->data) :
+			fr502_send(card, chan->dlci, 0, skb->len, skb->data)
+		;
+		if (err) ++chan->ifstats.tx_errors;
+		else ++chan->ifstats.tx_packets;
+	}
+	if (!retry)
+	{
+		dev_kfree_skb(skb, FREE_WRITE);
+		dev->tbusy = 0;
+	}
+	card->wandev.critical = 0;
+	return retry;
+}
+
+/*============================================================================
+ * Get ethernet-style interface statistics.
+ * Return a pointer to struct enet_statistics.
+ */
+static struct enet_statistics* if_stats (struct device* dev)
+{
+	fr_channel_t* chan = dev->priv;
+
+	return &chan->ifstats;
+}
+
+/****** Interrupt Handlers **************************************************/
+
+/*============================================================================
+ * S502 frame relay interrupt service routine.
+ */
+static void fr502_isr (sdla_t* card)
+{
+	fr502_flags_t* flags = card->flags;
+
+	switch (flags->iflag)
+	{
+	case 0x01:	/* receive interrupt */
+		fr502_rx_intr(card);
+		break;
+
+	case 0x02:	/* transmit interrupt */
+		flags->imask &= ~0x02;
+		tx_intr(card);
+		break;
+
+	default:
+		spur_intr(card);
+	}
+	flags->iflag = 0;
+}
+
+/*============================================================================
+ * S508 frame relay interrupt service routine.
+ */
+static void fr508_isr (sdla_t* card)
+{
+	fr508_flags_t* flags = card->flags;
+	fr_buf_ctl_t* bctl;
+
+	switch (flags->iflag)
+	{
+	case 0x01:	/* receive interrupt */
+		fr508_rx_intr(card);
+		break;
+
+	case 0x02:	/* transmit interrupt */
+		bctl = (void*)(flags->tse_offs - FR_MB_VECTOR +
+			card->hw.dpmbase)
+		;
+		bctl->flag = 0x90;	/* disable further Tx interrupts */
+		tx_intr(card);
+		break;
+
+	default:
+		spur_intr(card);
+	}
+	flags->iflag = 0;
+}
+
+/*============================================================================
+ * Receive interrupt handler.
+ */
+static void fr502_rx_intr (sdla_t* card)
+{
+	fr_mbox_t* mbox = card->rxmb;
+	struct sk_buff* skb;
+	struct device* dev;
+	fr_channel_t* chan;
+	unsigned dlci, len;
+	void* buf;
+
+	sdla_mapmem(&card->hw, FR502_RX_VECTOR);
+	dlci = mbox->cmd.dlci;
+	len  = mbox->cmd.length;
+
+	/* Find network interface for this packet */
+	dev = find_channel(card, dlci);
+	if (dev == NULL)
+	{
+		/* Invalid channel, discard packet */
+		printk(KERN_INFO "%s: receiving on orphaned DLCI %d!\n",
+			card->devname, dlci)
+		;
+		goto rx_done;
+	}
+	chan = dev->priv;
+	if (!dev->start)
+	{
+		++chan->ifstats.rx_dropped;
+		goto rx_done;
+	}
+
+	/* Allocate socket buffer */
+	skb = dev_alloc_skb(len);
+	if (skb == NULL)
+	{
+		printk(KERN_INFO "%s: no socket buffers available!\n",
+			card->devname)
+		;
+		++chan->ifstats.rx_dropped;
+		goto rx_done;
+	}
+
+	/* Copy data to the socket buffer */
+	buf = skb_put(skb, len);
+	memcpy(buf, mbox->data, len);
+	sdla_mapmem(&card->hw, FR_MB_VECTOR);
+
+	/* Decapsulate packet and pass it up the protocol stack */
+	skb->dev = dev;
+	buf = skb_pull(skb, 1);	/* remove hardware header */
+	if (!wan_type_trans(skb, dev))
+	{
+		/* can't decapsulate packet */
+		dev_kfree_skb(skb, FREE_READ);
+		++chan->ifstats.rx_errors;
+	}
+	else
+	{
+		netif_rx(skb);
+		++chan->ifstats.rx_packets;
+	}
+
+rx_done:
+	sdla_mapmem(&card->hw, FR_MB_VECTOR);
+}
+
+/*============================================================================
+ * Receive interrupt handler.
+ */
+static void fr508_rx_intr (sdla_t* card)
+{
+	fr_buf_ctl_t* frbuf = card->rxmb;
+	struct sk_buff* skb;
+	struct device* dev;
+	fr_channel_t* chan;
+	unsigned dlci, len, offs;
+	void* buf;
+
+	if (frbuf->flag != 0x01)
+	{
+		printk(KERN_INFO "%s: corrupted Rx buffer @ 0x%X!\n",
+			card->devname, (unsigned)frbuf)
+		;
+		return;
+	}
+	len  = frbuf->length;
+	dlci = frbuf->dlci;
+	offs = frbuf->offset;
+
+	/* Find network interface for this packet */
+	dev = find_channel(card, dlci);
+	if (dev == NULL)
+	{
+		/* Invalid channel, discard packet */
+		printk(KERN_INFO "%s: receiving on orphaned DLCI %d!\n",
+			card->devname, dlci)
+		;
+		goto rx_done;
+	}
+	chan = dev->priv;
+	if (!dev->start)
+	{
+		++chan->ifstats.rx_dropped;
+		goto rx_done;
+	}
+
+	/* Allocate socket buffer */
+	skb = dev_alloc_skb(len);
+	if (skb == NULL)
+	{
+		printk(KERN_INFO "%s: no socket buffers available!\n",
+			card->devname)
+		;
+		++chan->ifstats.rx_dropped;
+		goto rx_done;
+	}
+
+	/* Copy data to the socket buffer */
+	if ((offs + len) > card->u.f.rx_top)
+	{
+		unsigned tmp = card->u.f.rx_top - offs;
+
+		buf = skb_put(skb, tmp);
+		sdla_peek(&card->hw, offs, buf, tmp);
+		offs = card->u.f.rx_base;
+		len -= tmp;
+	}
+	buf = skb_put(skb, len);
+	sdla_peek(&card->hw, offs, buf, len);
+
+	/* Decapsulate packet and pass it up the protocol stack */
+	skb->dev = dev;
+	buf = skb_pull(skb, 1);	/* remove hardware header */
+	if (!wan_type_trans(skb, dev))
+	{
+		/* can't decapsulate packet */
+		dev_kfree_skb(skb, FREE_READ);
+		++chan->ifstats.rx_errors;
+	}
+	else
+	{
+		netif_rx(skb);
+		++chan->ifstats.rx_packets;
+	}
+
+rx_done:
+	/* Release buffer element and calculate a pointer to the next one */
+	frbuf->flag = 0;
+	card->rxmb = ++frbuf;
+	if ((void*)frbuf > card->u.f.rxmb_last)
+		card->rxmb = card->u.f.rxmb_base
+	;
+}
+
+/*============================================================================
+ * Transmit interrupt handler.
+ * o print a warning
+ * o 
+ * If number of spurious interrupts exceeded some limit, then ???
+ */
+static void tx_intr (sdla_t* card)
+{
+	printk(KERN_INFO "%s: transmit interrupt!\n", card->devname);
+}
+
+/*============================================================================
+ * Spurious interrupt handler.
+ * o print a warning
+ * o 
+ * If number of spurious interrupts exceeded some limit, then ???
+ */
+static void spur_intr (sdla_t* card)
+{
+	printk(KERN_INFO "%s: spurious interrupt!\n", card->devname);
+}
+
+/****** Background Polling Routines  ****************************************/
+
+/*============================================================================
+ * Main polling routine.
+ * This routine is repeatedly called by the WANPIPE 'thead' to allow for
+ * time-dependent housekeeping work.
+ *
+ * o fetch asynchronous network events.
+ *
+ * Notes:
+ * 1. This routine may be called on interrupt context with all interrupts
+ *    enabled. Beware!
+ */
+static void wpf_poll (sdla_t* card)
+{
+	fr502_flags_t* flags = card->flags;
+
+	if (flags->event)
+	{
+		fr_mbox_t* mbox = card->mbox;
+		int err;
+
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		mbox->cmd.command = FR_READ_STATUS;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+		if (err) fr_event(card, err, mbox);
+	}
+}
+
+/****** Frame Relay Firmware-Specific Functions *****************************/
+
+/*============================================================================
+ * Read firmware code version.
+ * o fill string str with firmware version info. 
+ */
+static int fr_read_version (sdla_t* card, char* str)
+{
+	fr_mbox_t* mbox = card->mbox;
+	int retry = MAX_CMD_RETRY;
+	int err;
+
+	do
+	{
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		mbox->cmd.command = FR_READ_CODE_VERSION;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+	}
+	while (err && retry-- && fr_event(card, err, mbox));
+	if (!err && str)
+	{
+		int len = mbox->cmd.length;
+
+		memcpy(str, mbox->data, len);
+	        str[len] = '\0';
+	}
+	return err;
+}
+
+/*============================================================================
+ * Set global configuration.
+ */
+static int fr_configure (sdla_t* card, fr_conf_t *conf)
+{
+	fr_mbox_t* mbox = card->mbox;
+	int retry = MAX_CMD_RETRY;
+	int dlci = card->u.f.node_dlci;
+	int dlci_num = card->u.f.dlci_num;
+	int err, i;
+
+	do
+	{
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		memcpy(mbox->data, conf, sizeof(fr_conf_t));
+		if (dlci_num) for (i = 0; i < dlci_num; ++i)
+			((fr_conf_t*)mbox->data)->dlci[i] = dlci + i
+		;
+		mbox->cmd.command = FR_SET_CONFIG;
+		mbox->cmd.length =
+			sizeof(fr_conf_t) + dlci_num * sizeof(short)
+		;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+	}
+	while (err && retry-- && fr_event(card, err, mbox));
+	return err;
+}
+
+/*============================================================================
+ * Set interrupt mode.
+ */
+static int fr_set_intr_mode (sdla_t* card, unsigned mode, unsigned mtu)
+{
+	fr_mbox_t* mbox = card->mbox;
+	int retry = MAX_CMD_RETRY;
+	int err;
+
+	do
+	{
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		if (card->hw.fwid == SFID_FR502)
+		{
+			fr502_intr_ctl_t* ictl = (void*)mbox->data;
+
+			memset(ictl, 0, sizeof(fr502_intr_ctl_t));
+			ictl->mode   = mode;
+			ictl->tx_len = mtu;
+			mbox->cmd.length = sizeof(fr502_intr_ctl_t);
+		}
+		else
+		{
+			fr508_intr_ctl_t* ictl = (void*)mbox->data;
+
+			memset(ictl, 0, sizeof(fr508_intr_ctl_t));
+			ictl->mode   = mode;
+			ictl->tx_len = mtu;
+			ictl->irq    = card->hw.irq;
+			mbox->cmd.length = sizeof(fr508_intr_ctl_t);
+		}
+		mbox->cmd.command = FR_SET_INTR_MODE;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+	}
+	while (err && retry-- && fr_event(card, err, mbox));
+	return err;
+}
+
+/*============================================================================
+ * Enable communications.
+ */
+static int fr_comm_enable (sdla_t* card)
+{
+	fr_mbox_t* mbox = card->mbox;
+	int retry = MAX_CMD_RETRY;
+	int err;
+
+	do
+	{
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		mbox->cmd.command = FR_COMM_ENABLE;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+	}
+	while (err && retry-- && fr_event(card, err, mbox));
+	return err;
+}
+
+/*============================================================================
+ * Disable communications. 
+ */
+static int fr_comm_disable (sdla_t* card)
+{
+	fr_mbox_t* mbox = card->mbox;
+	int retry = MAX_CMD_RETRY;
+	int err;
+
+	do
+	{
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		mbox->cmd.command = FR_COMM_DISABLE;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+	}
+	while (err && retry-- && fr_event(card, err, mbox));
+	return err;
+}
+
+/*============================================================================
+ * Add DLCI(s) (Access Node only!). 
+ */
+static int fr_add_dlci (sdla_t* card, int dlci, int num)
+{
+	fr_mbox_t* mbox = card->mbox;
+	int retry = MAX_CMD_RETRY;
+	int err, i;
+
+	do
+	{
+		unsigned short* dlci_list = (void*)mbox->data;
+
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		for (i = 0; i < num; ++i)
+			dlci_list[i] = dlci + i
+		;
+		mbox->cmd.length  = num * sizeof(short);
+		mbox->cmd.command = FR_ADD_DLCI;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+	}
+	while (err && retry-- && fr_event(card, err, mbox));
+	return err;
+}
+
+/*============================================================================
+ * Activate DLCI(s) (Access Node only!). 
+ */
+static int fr_activate_dlci (sdla_t* card, int dlci, int num)
+{
+	fr_mbox_t* mbox = card->mbox;
+	int retry = MAX_CMD_RETRY;
+	int err, i;
+
+	do
+	{
+		unsigned short* dlci_list = (void*)mbox->data;
+
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		for (i = 0; i < num; ++i)
+			dlci_list[i] = dlci + i
+		;
+		mbox->cmd.length  = num * sizeof(short);
+		mbox->cmd.command = FR_ACTIVATE_DLCI;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+	}
+	while (err && retry-- && fr_event(card, err, mbox));
+	return err;
+}
+
+/*============================================================================
+ * Issue in-channel signalling frame. 
+ */
+static int fr_issue_isf (sdla_t* card, int isf)
+{
+	fr_mbox_t* mbox = card->mbox;
+	int retry = MAX_CMD_RETRY;
+	int err;
+
+	do
+	{
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		mbox->data[0] = isf;
+		mbox->cmd.length  = 1;
+		mbox->cmd.command = FR_ISSUE_IS_FRAME;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+	}
+	while (err && retry-- && fr_event(card, err, mbox));
+	return err;
+}
+
+/*============================================================================
+ * Send a frame (S502 version). 
+ */
+static int fr502_send (sdla_t* card, int dlci, int attr, int len, void *buf)
+{
+	fr_mbox_t* mbox = card->mbox;
+	int retry = MAX_CMD_RETRY;
+	int err;
+
+	do
+	{
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		memcpy(mbox->data, buf, len);
+		mbox->cmd.dlci    = dlci;
+		mbox->cmd.attr    = attr;
+		mbox->cmd.length  = len;
+		mbox->cmd.command = FR_WRITE;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+	}
+	while (err && retry-- && fr_event(card, err, mbox));
+	return err;
+}
+
+/*============================================================================
+ * Send a frame (S508 version). 
+ */
+static int fr508_send (sdla_t* card, int dlci, int attr, int len, void *buf)
+{
+	fr_mbox_t* mbox = card->mbox;
+	int retry = MAX_CMD_RETRY;
+	int err;
+
+	do
+	{
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		mbox->cmd.dlci    = dlci;
+		mbox->cmd.attr    = attr;
+		mbox->cmd.length  = len;
+		mbox->cmd.command = FR_WRITE;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+	}
+	while (err && retry-- && fr_event(card, err, mbox));
+
+	if (!err)
+	{
+		fr_buf_ctl_t* frbuf = (void*)(*(unsigned long*)mbox->data -
+			FR_MB_VECTOR + card->hw.dpmbase)
+		;
+		unsigned long flags;
+
+		save_flags(flags);
+		cli();
+		sdla_poke(&card->hw, frbuf->offset, buf, len);
+		frbuf->flag = 0x01;
+		restore_flags(flags);
+	}
+	return err;
+}
+
+/****** Firmware Asynchronous Event Handlers ********************************/
+
+/*============================================================================
+ * Main asyncronous event/error handler.
+ *	This routine is called whenever firmware command returns non-zero
+ *	return code.
+ *
+ * Return zero if previous command has to be cancelled.
+ */
+static int fr_event (sdla_t *card, int event, fr_mbox_t* mbox)
+{
+	switch (event)
+	{
+	case FRRES_MODEM_FAILURE:
+		return fr_modem_failure(card, mbox);
+
+	case FRRES_CHANNEL_DOWN:
+		wanpipe_set_state(card, WAN_DISCONNECTED);
+		return 1;
+
+	case FRRES_CHANNEL_UP:
+		wanpipe_set_state(card, WAN_CONNECTED);
+		return 1;
+
+	case FRRES_DLCI_CHANGE:
+		return fr_dlci_change(card, mbox);
+
+	case FRRES_DLCI_MISMATCH:
+		printk(KERN_INFO "%s: DLCI list mismatch!\n", card->devname);
+		return 1;
+
+	case CMD_TIMEOUT:
+		printk(KERN_ERR "%s: command 0x%02X timed out!\n",
+			card->devname, mbox->cmd.command)
+		;
+		break;
+
+	default:
+		printk(KERN_INFO "%s: command 0x%02X returned 0x%02X!\n",
+			card->devname, mbox->cmd.command, event)
+		;
+	}
+	return 0;
+}
+
+/*============================================================================
+ * Handle modem error.
+ *
+ * Return zero if previous command has to be cancelled.
+ */
+static int fr_modem_failure (sdla_t *card, fr_mbox_t* mbox)
+{
+	printk(KERN_INFO "%s: physical link down! (modem error 0x%02X)\n",
+		card->devname, mbox->data[0])
+	;
+	switch (mbox->cmd.command)
+	{
+	case FR_WRITE:
+	case FR_READ:
+		return 0;
+	}
+	return 1;
+}
+
+/*============================================================================
+ * Handle DLCI status change.
+ *
+ * Return zero if previous command has to be cancelled.
+ */
+static int fr_dlci_change (sdla_t *card, fr_mbox_t* mbox)
+{
+	dlci_status_t* status = (void*)mbox->data;
+	int cnt = mbox->cmd.length / sizeof(dlci_status_t);
+
+	for (; cnt; --cnt, ++status)
+	{
+		unsigned short dlci = status->dlci;
+		struct device* dev = find_channel(card, dlci);
+
+		if (status->state & 0x01)
+		{
+			printk(KERN_INFO
+				"%s: DLCI %u has been deleted!\n",
+				card->devname, dlci)
+			;
+			if (dev && dev->start)
+				set_chan_state(dev, WAN_DISCONNECTED)
+			;
+		}
+		else if (status->state & 0x02)
+		{
+			printk(KERN_INFO
+				"%s: DLCI %u becomes active!\n",
+				card->devname, dlci)
+			;
+			if (dev && dev->start)
+				set_chan_state(dev, WAN_CONNECTED)
+			;
+		}
+	}
+	return 1;
+}
+
+/******* Miscellaneous ******************************************************/
+
+/*============================================================================
+ * Update channel state. 
+ */
+static int update_chan_state (struct device* dev)
+{
+	fr_channel_t* chan = dev->priv;
+	sdla_t* card = chan->card;
+	fr_mbox_t* mbox = card->mbox;
+	int retry = MAX_CMD_RETRY;
+	int err;
+
+	do
+	{
+		memset(&mbox->cmd, 0, sizeof(fr_cmd_t));
+		mbox->cmd.command = FR_LIST_ACTIVE_DLCI;
+		err = sdla_exec(mbox) ? mbox->cmd.result : CMD_TIMEOUT;
+	}
+	while (err && retry-- && fr_event(card, err, mbox));
+
+	if (!err)
+	{
+		unsigned short* list = (void*)mbox->data;
+		int cnt = mbox->cmd.length / sizeof(short);
+
+		for (; cnt; --cnt, ++list)
+		{
+			if (*list == chan->dlci)
+			{
+ 				set_chan_state(dev, WAN_CONNECTED);
+				break;
+			}
+		}
+	}
+	return err;
+}
+
+/*============================================================================
+ * Set channel state.
+ */
+static void set_chan_state (struct device* dev, int state)
+{
+	fr_channel_t* chan = dev->priv;
+	sdla_t* card = chan->card;
+	unsigned long flags;
+
+	save_flags(flags);
+	cli();
+	if (chan->state != state)
+	{
+		switch (state)
+		{
+		case WAN_CONNECTED:
+			printk (KERN_INFO "%s: interface %s connected!\n",
+				card->devname, dev->name)
+			;
+			break;
+
+		case WAN_CONNECTING:
+			printk (KERN_INFO "%s: interface %s connecting...\n",
+				card->devname, dev->name)
+			;
+			break;
+
+		case WAN_DISCONNECTED:
+			printk (KERN_INFO "%s: interface %s disconnected!\n",
+				card->devname, dev->name)
+			;
+			break;
+		}
+		chan->state = state;
+	}
+	chan->state_tick = jiffies;
+	restore_flags(flags);
+}
+
+/*============================================================================
+ * Find network device by its channel number.
+ */
+static struct device* find_channel (sdla_t* card, unsigned dlci)
+{
+	struct device* dev;
+
+	for (dev = card->wandev.dev; dev; dev = dev->slave)
+		if (((fr_channel_t*)dev->priv)->dlci == dlci) break
+	;
+	return dev;
+}
+
+/*============================================================================
+ * Check to see if a frame can be sent. If no transmit buffers available,
+ * enable transmit interrupts.
+ *
+ * Return:	1 - Tx buffer(s) available
+ *		0 - no buffers available
+ */
+static int is_tx_ready (sdla_t* card)
+{
+	if (card->hw.fwid == SFID_FR508)
+	{
+		fr508_flags_t* flags = card->flags;
+		unsigned char sb = inb(card->hw.port);
+
+		if (sb & 0x02) return 1;
+		flags->imask |= 0x02;
+	}
+	else
+	{
+		fr502_flags_t* flags = card->flags;
+
+		if (flags->tx_ready) return 1;
+		flags->imask |= 0x02;
+	}
+	return 0;
+}
+
+/*============================================================================
+ * Convert decimal string to unsigned integer.
+ * If len != 0 then only 'len' characters of the string are converted.
+ */
+static unsigned int dec_to_uint (unsigned char* str, int len)
+{
+	unsigned val;
+
+	if (!len) len = strlen(str);
+	for (val = 0; len && is_digit(*str); ++str, --len)
+		val = (val * 10) + (*str - (unsigned)'0')
+	;
+	return val;
+}
+
+/*============================================================================
+ * Convert hex string to unsigned integer.
+ * If len != 0 then only 'len' characters of the string are conferted.
+ */
+static unsigned int hex_to_uint (unsigned char* str, int len)
+{
+	unsigned val, ch;
+
+	if (!len) len = strlen(str);
+	for (val = 0; len; ++str, --len)
+	{
+		ch = *str;
+		if (is_digit(ch))
+			val = (val << 4) + (ch - (unsigned)'0')
+		;
+		else if (is_hex_digit(ch))
+			val = (val << 4) + ((ch & 0xDF) - (unsigned)'A' + 10)
+		;
+		else break;
+	}
+	return val;
+}
+
+/****** End *****************************************************************/
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen, slshen@lbl.gov