From: Esben Nielsen <simlo@phys.au.dk>

As previously reported the ArcNet driver didn't work with Preempt and SMB
on.  They do now.  I have changed the locking system from being a global
arcnet lock to being a lock per device.  I used the lock in
dev->hard_start_xmit = arcnet_send_packet.  

Furthermore I added the "CAP mode" encapsulation.  As far as I see it it is
the only encapsulation which actually makes ArcNet usefull over ethernet. 
Previously, the driver just ignored the hardware transmit status, now you
can get hardware acknowledge and excessive nacks back to userspace via a
raw socket.  The capmode.c is nearly just a copy of arc-rawmode.c.  The
difference is that it inserts a ack_tx() handle into the general driver
framework.

Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 25-akpm/drivers/net/arcnet/Kconfig        |   19 +
 25-akpm/drivers/net/arcnet/Makefile       |    1 
 25-akpm/drivers/net/arcnet/arc-rawmode.c  |    9 
 25-akpm/drivers/net/arcnet/arcnet.c       |  253 +++++++++++++++++--------
 25-akpm/drivers/net/arcnet/capmode.c      |  296 ++++++++++++++++++++++++++++++
 25-akpm/drivers/net/arcnet/com20020-isa.c |    1 
 25-akpm/drivers/net/arcnet/com20020.c     |   28 +-
 25-akpm/drivers/net/arcnet/rfc1051.c      |    3 
 25-akpm/drivers/net/arcnet/rfc1201.c      |    2 
 25-akpm/include/linux/arcdevice.h         |   21 +-
 25-akpm/include/linux/com20020.h          |   30 +--
 25-akpm/include/linux/if_arcnet.h         |   14 +
 25-akpm/include/linux/if_ether.h          |    1 
 include/linux/net.h                       |    0 
 14 files changed, 574 insertions(+), 104 deletions(-)

diff -puN drivers/net/arcnet/arcnet.c~arcnet-fixes drivers/net/arcnet/arcnet.c
--- 25/drivers/net/arcnet/arcnet.c~arcnet-fixes	2004-11-21 22:42:30.230086568 -0800
+++ 25-akpm/drivers/net/arcnet/arcnet.c	2004-11-21 22:42:30.254082920 -0800
@@ -53,7 +53,6 @@
 #include <linux/init.h>
 #include <linux/arcdevice.h>
 
-
 /* "do nothing" functions for protocol drivers */
 static void null_rx(struct net_device *dev, int bufnum,
 		    struct archdr *pkthdr, int length);
@@ -69,25 +68,28 @@ static int null_prepare_tx(struct net_de
  * arc_proto_default instead.  It also must not be NULL; if you would like
  * to set it to NULL, set it to &arc_proto_null instead.
  */
-struct ArcProto *arc_proto_map[256], *arc_proto_default, *arc_bcast_proto;
+ struct ArcProto *arc_proto_map[256], *arc_proto_default,
+   *arc_bcast_proto, *arc_raw_proto;
 
 struct ArcProto arc_proto_null =
 {
 	.suffix		= '?',
 	.mtu		= XMTU,
+	.is_ip          = 0,
 	.rx		= null_rx,
 	.build_header	= null_build_header,
 	.prepare_tx	= null_prepare_tx,
+	.continue_tx    = NULL,
+	.ack_tx         = NULL
 };
 
-static spinlock_t arcnet_lock = SPIN_LOCK_UNLOCKED;
-
 /* Exported function prototypes */
 int arcnet_debug = ARCNET_DEBUG;
 
 EXPORT_SYMBOL(arc_proto_map);
 EXPORT_SYMBOL(arc_proto_default);
 EXPORT_SYMBOL(arc_bcast_proto);
+EXPORT_SYMBOL(arc_raw_proto);
 EXPORT_SYMBOL(arc_proto_null);
 EXPORT_SYMBOL(arcnet_unregister_proto);
 EXPORT_SYMBOL(arcnet_debug);
@@ -131,7 +133,7 @@ static int __init arcnet_init(void)
 #endif
 
 	/* initialize the protocol map */
-	arc_proto_default = arc_bcast_proto = &arc_proto_null;
+	arc_raw_proto = arc_proto_default = arc_bcast_proto = &arc_proto_null;
 	for (count = 0; count < 256; count++)
 		arc_proto_map[count] = arc_proto_default;
 
@@ -155,7 +157,8 @@ module_exit(arcnet_exit);
  * Dump the contents of an sk_buff
  */
 #if ARCNET_DEBUG_MAX & D_SKB
-void arcnet_dump_skb(struct net_device *dev, struct sk_buff *skb, char *desc)
+void arcnet_dump_skb(struct net_device *dev,
+		     struct sk_buff *skb, char *desc)
 {
 	int i;
 
@@ -176,18 +179,22 @@ EXPORT_SYMBOL(arcnet_dump_skb);
  * Dump the contents of an ARCnet buffer
  */
 #if (ARCNET_DEBUG_MAX & (D_RX | D_TX))
-void arcnet_dump_packet(struct net_device *dev, int bufnum, char *desc)
+void arcnet_dump_packet(struct net_device *dev, int bufnum, char *desc,
+			int take_arcnet_lock)
 {
 	struct arcnet_local *lp = (struct arcnet_local *) dev->priv;
 	int i, length;
-	unsigned long flags;
+	unsigned long flags = 0;
 	static uint8_t buf[512];
 
 	/* hw.copy_from_card expects IRQ context so take the IRQ lock
 	   to keep it single threaded */
-	spin_lock_irqsave(&arcnet_lock, flags);
+	if(take_arcnet_lock)
+		spin_lock_irqsave(&lp->lock, flags);
+
 	lp->hw.copy_from_card(dev, bufnum, 0, buf, 512);
-	spin_unlock_irqrestore(&arcnet_lock, flags);
+	if(take_arcnet_lock)
+		spin_unlock_irqrestore(&lp->lock, flags);
 
 	/* if the offset[0] byte is nonzero, this is a 256-byte packet */
 	length = (buf[2] ? 256 : 512);
@@ -219,6 +226,8 @@ void arcnet_unregister_proto(struct ArcP
 		arc_proto_default = &arc_proto_null;
 	if (arc_bcast_proto == proto)
 		arc_bcast_proto = arc_proto_default;
+	if (arc_raw_proto == proto)
+		arc_raw_proto = arc_proto_default;
 
 	for (count = 0; count < 256; count++) {
 		if (arc_proto_map[count] == proto)
@@ -261,8 +270,11 @@ static int get_arcbuf(struct net_device 
 	struct arcnet_local *lp = (struct arcnet_local *) dev->priv;
 	int buf = -1, i;
 
-	if (!atomic_dec_and_test(&lp->buf_lock))	/* already in this function */
-		BUGMSG(D_NORMAL, "get_arcbuf: overlap (%d)!\n", lp->buf_lock.counter);
+	if (!atomic_dec_and_test(&lp->buf_lock)) {
+		/* already in this function */
+		BUGMSG(D_NORMAL, "get_arcbuf: overlap (%d)!\n",
+		       lp->buf_lock.counter);
+	}
 	else {			/* we can continue */
 		if (lp->next_buf >= 5)
 			lp->next_buf -= 5;
@@ -312,7 +324,7 @@ void arcdev_setup(struct net_device *dev
 	dev->mtu = choose_mtu();
 
 	dev->addr_len = ARCNET_ALEN;
-	dev->tx_queue_len = 30;
+	dev->tx_queue_len = 100;
 	dev->broadcast[0] = 0x00;	/* for us, broadcasts are address 0 */
 	dev->watchdog_timeo = TX_TIMEOUT;
 
@@ -334,8 +346,16 @@ void arcdev_setup(struct net_device *dev
 
 struct net_device *alloc_arcdev(char *name)
 {
-	return alloc_netdev(sizeof(struct arcnet_local),
-			    name && *name ? name : "arc%d", arcdev_setup);
+	struct net_device *dev;
+
+	dev = alloc_netdev(sizeof(struct arcnet_local),
+			   name && *name ? name : "arc%d", arcdev_setup);
+	if(dev) {
+		struct arcnet_local *lp = (struct arcnet_local *) dev->priv;
+		lp->lock = SPIN_LOCK_UNLOCKED;
+	}
+
+	return dev;
 }
 
 /*
@@ -351,6 +371,8 @@ static int arcnet_open(struct net_device
 	struct arcnet_local *lp = (struct arcnet_local *) dev->priv;
 	int count, newmtu, error;
 
+	BUGMSG(D_INIT,"opened.");
+
 	if (!try_module_get(lp->hw.owner))
 		return -ENODEV;
 
@@ -377,6 +399,8 @@ static int arcnet_open(struct net_device
 	if (newmtu < dev->mtu)
 		dev->mtu = newmtu;
 
+	BUGMSG(D_INIT, "arcnet_open: mtu: %d.\n", dev->mtu);
+
 	/* autodetect the encapsulation for each host. */
 	memset(lp->default_proto, 0, sizeof(lp->default_proto));
 
@@ -390,6 +414,7 @@ static int arcnet_open(struct net_device
 
 	/* initialize buffers */
 	atomic_set(&lp->buf_lock, 1);
+
 	lp->next_buf = lp->first_free_buf = 0;
 	release_arcbuf(dev, 0);
 	release_arcbuf(dev, 1);
@@ -411,17 +436,24 @@ static int arcnet_open(struct net_device
 		BUGMSG(D_NORMAL, "WARNING!  Station address FF may confuse "
 		       "DOS networking programs!\n");
 
-	if (ASTATUS() & RESETflag)
+	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
+	if (ASTATUS() & RESETflag) {
+	  	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
 		ACOMMAND(CFLAGScmd | RESETclear);
+	}
+
 
+	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
 	/* make sure we're ready to receive IRQ's. */
 	AINTMASK(0);
 	udelay(1);		/* give it time to set the mask before
 				 * we reset it again. (may not even be
 				 * necessary)
 				 */
+	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
 	lp->intmask = NORXflag | RECONflag;
 	AINTMASK(lp->intmask);
+	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
 
 	netif_start_queue(dev);
 
@@ -467,32 +499,41 @@ static int arcnet_header(struct sk_buff 
 	       daddr ? *(uint8_t *) daddr : -1,
 	       type, type, len);
 
-	if (len != skb->len)
+	if (skb->len!=0 && len != skb->len)
 		BUGMSG(D_NORMAL, "arcnet_header: Yikes!  skb->len(%d) != len(%d)!\n",
 		       skb->len, len);
 
-	/*
-	 * if the dest addr isn't provided, we can't choose an encapsulation!
-	 * Store the packet type (eg. ETH_P_IP) for now, and we'll push on a
-	 * real header when we do rebuild_header. 
-	 */
-	if (!daddr) {
+
+  	/* Type is host order - ? */
+  	if(type == ETH_P_ARCNET) {
+  		proto = arc_raw_proto;
+  		BUGMSG(D_DEBUG, "arc_raw_proto used. proto='%c'\n",proto->suffix);
+  		_daddr = daddr ? *(uint8_t *) daddr : 0;
+  	}
+	else if (!daddr) {
+		/*
+		 * if the dest addr isn't provided, we can't choose an encapsulation!
+		 * Store the packet type (eg. ETH_P_IP) for now, and we'll push on a
+		 * real header when we do rebuild_header.
+		 */
 		*(uint16_t *) skb_push(skb, 2) = type;
 		if (skb->nh.raw - skb->mac.raw != 2)
 			BUGMSG(D_NORMAL, "arcnet_header: Yikes!  diff (%d) is not 2!\n",
 			       (int)(skb->nh.raw - skb->mac.raw));
 		return -2;	/* return error -- can't transmit yet! */
 	}
-	/* otherwise, we can just add the header as usual. */
-	_daddr = *(uint8_t *) daddr;
-	proto_num = lp->default_proto[_daddr];
-	proto = arc_proto_map[proto_num];
-	BUGMSG(D_DURING, "building header for %02Xh using protocol '%c'\n",
-	       proto_num, proto->suffix);
-	if (proto == &arc_proto_null && arc_bcast_proto != proto) {
-		BUGMSG(D_DURING, "actually, let's use '%c' instead.\n",
-		       arc_bcast_proto->suffix);
-		proto = arc_bcast_proto;
+	else {
+		/* otherwise, we can just add the header as usual. */
+		_daddr = *(uint8_t *) daddr;
+		proto_num = lp->default_proto[_daddr];
+		proto = arc_proto_map[proto_num];
+		BUGMSG(D_DURING, "building header for %02Xh using protocol '%c'\n",
+		       proto_num, proto->suffix);
+		if (proto == &arc_proto_null && arc_bcast_proto != proto) {
+			BUGMSG(D_DURING, "actually, let's use '%c' instead.\n",
+			       arc_bcast_proto->suffix);
+			proto = arc_bcast_proto;
+		}
 	}
 	return proto->build_header(skb, dev, type, _daddr);
 }
@@ -519,6 +560,7 @@ static int arcnet_rebuild_header(struct 
 		return 0;
 	}
 	type = *(uint16_t *) skb_pull(skb, 2);
+	BUGMSG(D_DURING, "rebuild header for protocol %Xh\n", type);
 
 	if (type == ETH_P_IP) {
 #ifdef CONFIG_INET
@@ -555,10 +597,12 @@ static int arcnet_send_packet(struct sk_
 	struct arc_rfc1201 *soft;
 	struct ArcProto *proto;
 	int txbuf;
+	unsigned long flags;
+	int freeskb = 0;
 
 	BUGMSG(D_DURING,
-	       "transmit requested (status=%Xh, txbufs=%d/%d, len=%d)\n",
-	       ASTATUS(), lp->cur_tx, lp->next_tx, skb->len);
+	       "transmit requested (status=%Xh, txbufs=%d/%d, len=%d, protocol %x)\n",
+	       ASTATUS(), lp->cur_tx, lp->next_tx, skb->len,skb->protocol);
 
 	pkt = (struct archdr *) skb->data;
 	soft = &pkt->soft.rfc1201;
@@ -578,38 +622,49 @@ static int arcnet_send_packet(struct sk_
 	/* We're busy transmitting a packet... */
 	netif_stop_queue(dev);
 
+	spin_lock_irqsave(&lp->lock, flags);
 	AINTMASK(0);
 
 	txbuf = get_arcbuf(dev);
 	if (txbuf != -1) {
-		if (proto->prepare_tx(dev, pkt, skb->len, txbuf)) {
-			/* done right away */
+		if (proto->prepare_tx(dev, pkt, skb->len, txbuf) &&
+		    !proto->ack_tx) {
+			/* done right away and we don't want to acknowledge
+			   the package later - forget about it now */
 			lp->stats.tx_bytes += skb->len;
-			dev_kfree_skb(skb);
+			freeskb = 1;
 		} else {
 			/* do it the 'split' way */
 			lp->outgoing.proto = proto;
 			lp->outgoing.skb = skb;
 			lp->outgoing.pkt = pkt;
 
-			if (!proto->continue_tx)
-				BUGMSG(D_NORMAL, "bug! prep_tx==0, but no continue_tx!\n");
-			else if (proto->continue_tx(dev, txbuf)) {
-				BUGMSG(D_NORMAL,
-				       "bug! continue_tx finished the first time! "
-				       "(proto='%c')\n", proto->suffix);
+			if (proto->continue_tx &&
+			    proto->continue_tx(dev, txbuf)) {
+			  BUGMSG(D_NORMAL,
+				 "bug! continue_tx finished the first time! "
+				 "(proto='%c')\n", proto->suffix);
 			}
 		}
 
 		lp->next_tx = txbuf;
-	} else
-		dev_kfree_skb(skb);
+	} else {
+		freeskb = 1;
+	}
 
+	BUGMSG(D_DEBUG, "%s: %d: %s, status: %x\n",__FILE__,__LINE__,__FUNCTION__,ASTATUS());
 	/* make sure we didn't ignore a TX IRQ while we were in here */
 	AINTMASK(0);
-	lp->intmask |= TXFREEflag;
+
+	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
+	lp->intmask |= TXFREEflag|EXCNAKflag;
 	AINTMASK(lp->intmask);
+	BUGMSG(D_DEBUG, "%s: %d: %s, status: %x\n",__FILE__,__LINE__,__FUNCTION__,ASTATUS());
 
+	spin_unlock_irqrestore(&lp->lock, flags);
+	if (freeskb) {
+		dev_kfree_skb(skb);
+	}
 	return 0;		/* no need to try again */
 }
 
@@ -628,7 +683,7 @@ static int go_tx(struct net_device *dev)
 	if (lp->cur_tx != -1 || lp->next_tx == -1)
 		return 0;
 
-	BUGLVL(D_TX) arcnet_dump_packet(dev, lp->next_tx, "go_tx");
+	BUGLVL(D_TX) arcnet_dump_packet(dev, lp->next_tx, "go_tx", 0);
 
 	lp->cur_tx = lp->next_tx;
 	lp->next_tx = -1;
@@ -640,7 +695,8 @@ static int go_tx(struct net_device *dev)
 	lp->stats.tx_packets++;
 	lp->lasttrans_dest = lp->lastload_dest;
 	lp->lastload_dest = 0;
-	lp->intmask |= TXFREEflag;
+	lp->excnak_pending = 0;
+	lp->intmask |= TXFREEflag|EXCNAKflag;
 
 	return 1;
 }
@@ -654,7 +710,7 @@ static void arcnet_timeout(struct net_de
 	int status = ASTATUS();
 	char *msg;
 
-	spin_lock_irqsave(&arcnet_lock, flags);
+	spin_lock_irqsave(&lp->lock, flags);
 	if (status & TXFREEflag) {	/* transmit _DID_ finish */
 		msg = " - missed IRQ?";
 	} else {
@@ -665,12 +721,12 @@ static void arcnet_timeout(struct net_de
 	}
 	lp->stats.tx_errors++;
 
-	/* make sure we didn't miss a TX IRQ */
+	/* make sure we didn't miss a TX or a EXC NAK IRQ */
 	AINTMASK(0);
-	lp->intmask |= TXFREEflag;
+	lp->intmask |= TXFREEflag|EXCNAKflag;
 	AINTMASK(lp->intmask);
 	
-	spin_unlock_irqrestore(&arcnet_lock, flags);
+	spin_unlock_irqrestore(&lp->lock, flags);
 
 	if (jiffies - lp->last_timeout > 10*HZ) {
 		BUGMSG(D_EXTRA, "tx timed out%s (status=%Xh, intmask=%Xh, dest=%02Xh)\n",
@@ -692,18 +748,19 @@ irqreturn_t arcnet_interrupt(int irq, vo
 {
 	struct net_device *dev = dev_id;
 	struct arcnet_local *lp;
-	int recbuf, status, didsomething, boguscount;
+	int recbuf, status, diagstatus, didsomething, boguscount;
+	int retval = IRQ_NONE;
 
 	BUGMSG(D_DURING, "\n");
 
 	BUGMSG(D_DURING, "in arcnet_interrupt\n");
-
-	spin_lock(&arcnet_lock);
 	
 	lp = (struct arcnet_local *) dev->priv;
 	if (!lp)
 		BUG();
 		
+	spin_lock(&lp->lock);
+
 	/*
 	 * RESET flag was enabled - if device is not running, we must clear it right
 	 * away (but nothing else).
@@ -712,7 +769,7 @@ irqreturn_t arcnet_interrupt(int irq, vo
 		if (ASTATUS() & RESETflag)
 			ACOMMAND(CFLAGScmd | RESETclear);
 		AINTMASK(0);
-		spin_unlock(&arcnet_lock);
+		spin_unlock(&lp->lock);
 		return IRQ_HANDLED;
 	}
 
@@ -722,6 +779,10 @@ irqreturn_t arcnet_interrupt(int irq, vo
 	boguscount = 5;
 	do {
 		status = ASTATUS();
+                diagstatus = (status >> 8) & 0xFF;
+
+		BUGMSG(D_DEBUG, "%s: %d: %s: status=%x\n",
+			__FILE__,__LINE__,__FUNCTION__,status);
 		didsomething = 0;
 
 		/*
@@ -761,24 +822,55 @@ irqreturn_t arcnet_interrupt(int irq, vo
 			}
 			didsomething++;
 		}
+
+		if((diagstatus & EXCNAKflag)) {
+			BUGMSG(D_DURING, "EXCNAK IRQ (diagstat=%Xh)\n",
+			       diagstatus);
+
+                        ACOMMAND(NOTXcmd);      /* disable transmit */
+                        lp->excnak_pending = 1;
+
+                        ACOMMAND(EXCNAKclear);
+			lp->intmask &= ~(EXCNAKflag);
+                        didsomething++;
+                }
+
+
 		/* a transmit finished, and we're interested in it. */
 		if ((status & lp->intmask & TXFREEflag) || lp->timed_out) {
-			lp->intmask &= ~TXFREEflag;
+			lp->intmask &= ~(TXFREEflag|EXCNAKflag);
 
 			BUGMSG(D_DURING, "TX IRQ (stat=%Xh)\n", status);
 
-			if (lp->cur_tx != -1 && !(status & TXACKflag) && !lp->timed_out) {
-				if (lp->lasttrans_dest != 0) {
-					BUGMSG(D_EXTRA, "transmit was not acknowledged! "
-					    "(status=%Xh, dest=%02Xh)\n",
-					     status, lp->lasttrans_dest);
-					lp->stats.tx_errors++;
-					lp->stats.tx_carrier_errors++;
-				} else {
-					BUGMSG(D_DURING,
-					       "broadcast was not acknowledged; that's normal "
-					    "(status=%Xh, dest=%02Xh)\n",
-					     status, lp->lasttrans_dest);
+			if (lp->cur_tx != -1 && !lp->timed_out) {
+				if(!(status & TXACKflag)) {
+					if (lp->lasttrans_dest != 0) {
+						BUGMSG(D_EXTRA,
+						       "transmit was not acknowledged! "
+						       "(status=%Xh, dest=%02Xh)\n",
+						       status, lp->lasttrans_dest);
+						lp->stats.tx_errors++;
+						lp->stats.tx_carrier_errors++;
+					} else {
+						BUGMSG(D_DURING,
+						       "broadcast was not acknowledged; that's normal "
+						       "(status=%Xh, dest=%02Xh)\n",
+						       status, lp->lasttrans_dest);
+					}
+				}
+
+				if (lp->outgoing.proto &&
+				    lp->outgoing.proto->ack_tx) {
+				  int ackstatus;
+				  if(status & TXACKflag)
+                                    ackstatus=2;
+                                  else if(lp->excnak_pending)
+                                    ackstatus=1;
+                                  else
+                                    ackstatus=0;
+
+                                  lp->outgoing.proto
+                                    ->ack_tx(dev, ackstatus);
 				}
 			}
 			if (lp->cur_tx != -1)
@@ -798,8 +890,11 @@ irqreturn_t arcnet_interrupt(int irq, vo
 					if (lp->outgoing.proto->continue_tx(dev, txbuf)) {
 						/* that was the last segment */
 						lp->stats.tx_bytes += lp->outgoing.skb->len;
-						dev_kfree_skb_irq(lp->outgoing.skb);
-						lp->outgoing.proto = NULL;
+						if(!lp->outgoing.proto->ack_tx)
+						  {
+						    dev_kfree_skb_irq(lp->outgoing.skb);
+						    lp->outgoing.proto = NULL;
+						  }
 					}
 					lp->next_tx = txbuf;
 				}
@@ -810,7 +905,7 @@ irqreturn_t arcnet_interrupt(int irq, vo
 		}
 		/* now process the received packet, if any */
 		if (recbuf != -1) {
-			BUGLVL(D_RX) arcnet_dump_packet(dev, recbuf, "rx irq");
+			BUGLVL(D_RX) arcnet_dump_packet(dev, recbuf, "rx irq", 0);
 
 			arcnet_rx(dev, recbuf);
 			release_arcbuf(dev, recbuf);
@@ -868,6 +963,10 @@ irqreturn_t arcnet_interrupt(int irq, vo
 
 			BUGMSG(D_DURING, "not recon: clearing counters anyway.\n");
 		}
+
+		if(didsomething) {
+			retval |= IRQ_HANDLED;
+		}
 	}
 	while (--boguscount && didsomething);
 
@@ -880,8 +979,8 @@ irqreturn_t arcnet_interrupt(int irq, vo
 	udelay(1);
 	AINTMASK(lp->intmask);
 	
-	spin_unlock(&arcnet_lock);
-	return IRQ_RETVAL(didsomething);
+	spin_unlock(&lp->lock);
+	return retval;
 }
 
 
@@ -908,7 +1007,7 @@ void arcnet_rx(struct net_device *dev, i
 	}
 
 	/* get the full header, if possible */
-	if (sizeof(pkt.soft) < length)
+	if (sizeof(pkt.soft) <= length)
 		lp->hw.copy_from_card(dev, bufnum, ofs, soft, sizeof(pkt.soft));
 	else {
 		memset(&pkt.soft, 0, sizeof(pkt.soft));
@@ -923,7 +1022,7 @@ void arcnet_rx(struct net_device *dev, i
 	lp->stats.rx_bytes += length + ARC_HDR_SIZE;
 
 	/* call the right receiver for the protocol */
-	if (arc_proto_map[soft->proto] != &arc_proto_null) {
+	if (arc_proto_map[soft->proto]->is_ip) {
 		BUGLVL(D_PROTO) {
 			struct ArcProto
 			*oldp = arc_proto_map[lp->default_proto[pkt.hard.source]],
diff -puN drivers/net/arcnet/arc-rawmode.c~arcnet-fixes drivers/net/arcnet/arc-rawmode.c
--- 25/drivers/net/arcnet/arc-rawmode.c~arcnet-fixes	2004-11-21 22:42:30.232086264 -0800
+++ 25-akpm/drivers/net/arcnet/arc-rawmode.c	2004-11-21 22:42:30.254082920 -0800
@@ -42,7 +42,6 @@ static int build_header(struct sk_buff *
 static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length,
 		      int bufnum);
 
-
 struct ArcProto rawmode_proto =
 {
 	.suffix		= 'r',
@@ -50,6 +49,8 @@ struct ArcProto rawmode_proto =
 	.rx		= rx,
 	.build_header	= build_header,
 	.prepare_tx	= prepare_tx,
+	.continue_tx    = NULL,
+	.ack_tx         = NULL
 };
 
 
@@ -121,7 +122,8 @@ static void rx(struct net_device *dev, i
 
 	BUGLVL(D_SKB) arcnet_dump_skb(dev, skb, "rx");
 
-	skb->protocol = 0;
+	skb->protocol = __constant_htons(ETH_P_ARCNET);
+;
 	netif_rx(skb);
 	dev->last_rx = jiffies;
 }
@@ -190,6 +192,9 @@ static int prepare_tx(struct net_device 
 	} else
 		hard->offset[0] = ofs = 256 - length;
 
+	BUGMSG(D_DURING, "prepare_tx: length=%d ofs=%d\n",
+	       length,ofs);
+
 	lp->hw.copy_to_card(dev, bufnum, 0, hard, ARC_HDR_SIZE);
 	lp->hw.copy_to_card(dev, bufnum, ofs, &pkt->soft, length);
 
diff -puN /dev/null drivers/net/arcnet/capmode.c
--- /dev/null	2003-09-15 06:40:47.000000000 -0700
+++ 25-akpm/drivers/net/arcnet/capmode.c	2004-11-21 22:42:30.256082616 -0800
@@ -0,0 +1,296 @@
+/*
+ * Linux ARCnet driver - "cap mode" packet encapsulation.
+ * It adds sequence numbers to packets for communicating between a user space
+ * application and the driver. After a transmit it sends a packet with protocol
+ * byte 0 back up to the userspace containing the sequence number of the packet
+ * plus the transmit-status on the ArcNet.
+ *
+ * Written 2002-4 by Esben Nielsen, Vestas Wind Systems A/S
+ * Derived from arc-rawmode.c by Avery Pennarun.
+ * arc-rawmode was in turned based on skeleton.c, see below.
+ *
+ * **********************
+ *
+ * The original copyright of skeleton.c was as follows:
+ *
+ * skeleton.c Written 1993 by Donald Becker.
+ * Copyright 1993 United States Government as represented by the
+ * Director, National Security Agency.  This software may only be used
+ * and distributed according to the terms of the GNU General Public License as
+ * modified by SRC, incorporated herein by reference.
+ *
+ * **********************
+ *
+ * For more details, see drivers/net/arcnet.c
+ *
+ * **********************
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/if_arp.h>
+#include <net/arp.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/arcdevice.h>
+
+#define VERSION "arcnet: cap mode (`c') encapsulation support loaded.\n"
+
+
+static void rx(struct net_device *dev, int bufnum,
+	       struct archdr *pkthdr, int length);
+static int build_header(struct sk_buff *skb,
+			struct net_device *dev,
+			unsigned short type,
+			uint8_t daddr);
+static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length,
+		      int bufnum);
+static int ack_tx(struct net_device *dev, int acked);
+
+
+struct ArcProto capmode_proto =
+{
+	'r',
+	XMTU,
+	0,
+       	rx,
+	build_header,
+	prepare_tx,
+	NULL,
+	ack_tx
+};
+
+
+void arcnet_cap_init(void)
+{
+	int count;
+
+	for (count = 1; count <= 8; count++)
+		if (arc_proto_map[count] == arc_proto_default)
+			arc_proto_map[count] = &capmode_proto;
+
+	/* for cap mode, we only set the bcast proto if there's no better one */
+	if (arc_bcast_proto == arc_proto_default)
+		arc_bcast_proto = &capmode_proto;
+
+	arc_proto_default = &capmode_proto;
+	arc_raw_proto = &capmode_proto;
+}
+
+
+#ifdef MODULE
+
+int __init init_module(void)
+{
+	printk(VERSION);
+	arcnet_cap_init();
+	return 0;
+}
+
+void cleanup_module(void)
+{
+	arcnet_unregister_proto(&capmode_proto);
+}
+
+MODULE_LICENSE("GPL");
+#endif				/* MODULE */
+
+
+
+/* packet receiver */
+static void rx(struct net_device *dev, int bufnum,
+	       struct archdr *pkthdr, int length)
+{
+	struct arcnet_local *lp = (struct arcnet_local *) dev->priv;
+	struct sk_buff *skb;
+	struct archdr *pkt = pkthdr;
+	char *pktbuf, *pkthdrbuf;
+	int ofs;
+
+	BUGMSG(D_DURING, "it's a raw(cap) packet (length=%d)\n", length);
+
+	if (length >= MinTU)
+		ofs = 512 - length;
+	else
+		ofs = 256 - length;
+
+	skb = alloc_skb(length + ARC_HDR_SIZE + sizeof(int), GFP_ATOMIC);
+	if (skb == NULL) {
+		BUGMSG(D_NORMAL, "Memory squeeze, dropping packet.\n");
+		lp->stats.rx_dropped++;
+		return;
+	}
+	skb_put(skb, length + ARC_HDR_SIZE + sizeof(int));
+	skb->dev = dev;
+
+	pkt = (struct archdr *) skb->data;
+
+	skb->mac.raw = skb->data;
+	skb_pull(skb, ARC_HDR_SIZE);
+
+	/* up to sizeof(pkt->soft) has already been copied from the card */
+	/* squeeze in an int for the cap encapsulation */
+
+	/* use these variables to be sure we count in bytes, not in
+	   sizeof(struct archdr) */
+	pktbuf=(char*)pkt;
+	pkthdrbuf=(char*)pkthdr;
+	memcpy(pktbuf, pkthdrbuf, ARC_HDR_SIZE+sizeof(pkt->soft.cap.proto));
+	memcpy(pktbuf+ARC_HDR_SIZE+sizeof(pkt->soft.cap.proto)+sizeof(int),
+	       pkthdrbuf+ARC_HDR_SIZE+sizeof(pkt->soft.cap.proto),
+	       sizeof(struct archdr)-ARC_HDR_SIZE-sizeof(pkt->soft.cap.proto));
+
+	if (length > sizeof(pkt->soft))
+		lp->hw.copy_from_card(dev, bufnum, ofs + sizeof(pkt->soft),
+				      pkt->soft.raw + sizeof(pkt->soft)
+				      + sizeof(int),
+				      length - sizeof(pkt->soft));
+
+	BUGLVL(D_SKB) arcnet_dump_skb(dev, skb, "rx");
+
+	skb->protocol = __constant_htons(ETH_P_ARCNET);
+;
+	netif_rx(skb);
+	dev->last_rx = jiffies;
+}
+
+
+/*
+ * Create the ARCnet hard/soft headers for cap mode.
+ * There aren't any soft headers in cap mode - not even the protocol id.
+ */
+static int build_header(struct sk_buff *skb,
+			struct net_device *dev,
+			unsigned short type,
+			uint8_t daddr)
+{
+	int hdr_size = ARC_HDR_SIZE;
+	struct archdr *pkt = (struct archdr *) skb_push(skb, hdr_size);
+
+	BUGMSG(D_PROTO, "Preparing header for cap packet %x.\n",
+	       *((int*)&pkt->soft.cap.cookie[0]));
+	/*
+	 * Set the source hardware address.
+	 *
+	 * This is pretty pointless for most purposes, but it can help in
+	 * debugging.  ARCnet does not allow us to change the source address in
+	 * the actual packet sent)
+	 */
+	pkt->hard.source = *dev->dev_addr;
+
+	/* see linux/net/ethernet/eth.c to see where I got the following */
+
+	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) {
+		/*
+		 * FIXME: fill in the last byte of the dest ipaddr here to better
+		 * comply with RFC1051 in "noarp" mode.
+		 */
+		pkt->hard.dest = 0;
+		return hdr_size;
+	}
+	/* otherwise, just fill it in and go! */
+	pkt->hard.dest = daddr;
+
+	return hdr_size;	/* success */
+}
+
+
+static int prepare_tx(struct net_device *dev, struct archdr *pkt, int length,
+		      int bufnum)
+{
+	struct arcnet_local *lp = (struct arcnet_local *) dev->priv;
+	struct arc_hardware *hard = &pkt->hard;
+	int ofs;
+
+
+	/* hard header is not included in packet length */
+	length -= ARC_HDR_SIZE;
+	/* And neither is the cookie field */
+	length -= sizeof(int);
+
+	BUGMSG(D_DURING, "prepare_tx: txbufs=%d/%d/%d\n",
+	       lp->next_tx, lp->cur_tx, bufnum);
+
+	BUGMSG(D_PROTO, "Sending for cap packet %x.\n",
+	       *((int*)&pkt->soft.cap.cookie[0]));
+
+	if (length > XMTU) {
+		/* should never happen! other people already check for this. */
+		BUGMSG(D_NORMAL, "Bug!  prepare_tx with size %d (> %d)\n",
+		       length, XMTU);
+		length = XMTU;
+	}
+	if (length > MinTU) {
+		hard->offset[0] = 0;
+		hard->offset[1] = ofs = 512 - length;
+	} else if (length > MTU) {
+		hard->offset[0] = 0;
+		hard->offset[1] = ofs = 512 - length - 3;
+	} else
+		hard->offset[0] = ofs = 256 - length;
+
+	BUGMSG(D_DURING, "prepare_tx: length=%d ofs=%d\n",
+	       length,ofs);
+
+	// Copy the arcnet-header + the protocol byte down:
+	lp->hw.copy_to_card(dev, bufnum, 0, hard, ARC_HDR_SIZE);
+	lp->hw.copy_to_card(dev, bufnum, ofs, &pkt->soft.cap.proto,
+			    sizeof(pkt->soft.cap.proto));
+
+	// Skip the extra integer we have written into it as a cookie
+	// but write the rest of the message:
+	lp->hw.copy_to_card(dev, bufnum, ofs+1,
+			    ((unsigned char*)&pkt->soft.cap.mes),length-1);
+
+	lp->lastload_dest = hard->dest;
+
+	return 1;		/* done */
+}
+
+
+static int ack_tx(struct net_device *dev, int acked)
+{
+  struct arcnet_local *lp = (struct arcnet_local *) dev->priv;
+  struct sk_buff *ackskb;
+  struct archdr *ackpkt;
+  int length=sizeof(struct arc_cap);
+
+  BUGMSG(D_DURING, "capmode: ack_tx: protocol: %x: result: %d\n",
+	 lp->outgoing.skb->protocol, acked);
+
+  BUGLVL(D_SKB) arcnet_dump_skb(dev, lp->outgoing.skb, "ack_tx");
+
+  /* Now alloc a skb to send back up through the layers: */
+  ackskb = alloc_skb(length + ARC_HDR_SIZE , GFP_ATOMIC);
+  if (ackskb == NULL) {
+	  BUGMSG(D_NORMAL, "Memory squeeze, can't acknowledge.\n");
+	  goto free_outskb;
+  }
+
+  skb_put(ackskb, length + ARC_HDR_SIZE );
+  ackskb->dev = dev;
+
+  ackpkt = (struct archdr *) ackskb->data;
+
+  ackskb->mac.raw = ackskb->data;
+  /* skb_pull(ackskb, ARC_HDR_SIZE); */
+
+
+  memcpy(ackpkt, lp->outgoing.skb->data, ARC_HDR_SIZE+sizeof(struct arc_cap));
+  ackpkt->soft.cap.proto=0; /* using protocol 0 for acknowledge */
+  ackpkt->soft.cap.mes.ack=acked;
+
+  BUGMSG(D_PROTO, "Ackknowledge for cap packet %x.\n",
+	 *((int*)&ackpkt->soft.cap.cookie[0]));
+
+  ackskb->protocol = __constant_htons(ETH_P_ARCNET);
+
+  BUGLVL(D_SKB) arcnet_dump_skb(dev, ackskb, "ack_tx_recv");
+  netif_rx(ackskb);
+
+ free_outskb:
+  dev_kfree_skb_irq(lp->outgoing.skb);
+  lp->outgoing.proto = NULL; /* We are always finished when in this protocol */
+
+  return 0;
+}
diff -puN drivers/net/arcnet/com20020.c~arcnet-fixes drivers/net/arcnet/com20020.c
--- 25/drivers/net/arcnet/com20020.c~arcnet-fixes	2004-11-21 22:42:30.233086112 -0800
+++ 25-akpm/drivers/net/arcnet/com20020.c	2004-11-21 22:42:30.257082464 -0800
@@ -117,7 +117,7 @@ int com20020_check(struct net_device *de
 	lp->config = 0x21 | (lp->timeout << 3) | (lp->backplane << 2);
 	/* set node ID to 0x42 (but transmitter is disabled, so it's okay) */
 	SETCONF;
-	outb(0x42, ioaddr + 7);
+	outb(0x42, ioaddr + BUS_ALIGN*7);
 
 	status = ASTATUS();
 
@@ -129,7 +129,7 @@ int com20020_check(struct net_device *de
 
 	/* Enable TX */
 	outb(0x39, _CONFIG);
-	outb(inb(ioaddr + 8), ioaddr + 7);
+	outb(inb(ioaddr + BUS_ALIGN*8), ioaddr + BUS_ALIGN*7);
 
 	ACOMMAND(CFLAGScmd | RESETclear | CONFIGclear);
 
@@ -173,7 +173,7 @@ int com20020_found(struct net_device *de
 	dev->set_multicast_list = com20020_set_mc_list;
 
 	if (!dev->dev_addr[0])
-		dev->dev_addr[0] = inb(ioaddr + 8);	/* FIXME: do this some other way! */
+		dev->dev_addr[0] = inb(ioaddr + BUS_ALIGN*8);	/* FIXME: do this some other way! */
 
 	SET_SUBADR(SUB_SETUP1);
 	outb(lp->setup, _XREG);
@@ -188,7 +188,6 @@ int com20020_found(struct net_device *de
 		outb(0x18, _COMMAND);
 	}
 
-
 	lp->config = 0x20 | (lp->timeout << 3) | (lp->backplane << 2) | 1;
 	/* Default 0x38 + register: Node ID */
 	SETCONF;
@@ -235,15 +234,19 @@ int com20020_found(struct net_device *de
 static int com20020_reset(struct net_device *dev, int really_reset)
 {
 	struct arcnet_local *lp = (struct arcnet_local *) dev->priv;
-	short ioaddr = dev->base_addr;
+	u_int ioaddr = dev->base_addr;
 	u_char inbyte;
 
+	BUGMSG(D_DEBUG, "%s: %d: %s: dev: %p, lp: %p, dev->name: %s\n",
+		__FILE__,__LINE__,__FUNCTION__,dev,lp,dev->name);
 	BUGMSG(D_INIT, "Resetting %s (status=%02Xh)\n",
 	       dev->name, ASTATUS());
 
+	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
 	lp->config = TXENcfg | (lp->timeout << 3) | (lp->backplane << 2);
 	/* power-up defaults */
 	SETCONF;
+	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
 
 	if (really_reset) {
 		/* reset the card */
@@ -251,17 +254,22 @@ static int com20020_reset(struct net_dev
 		mdelay(RESETtime * 2);	/* COM20020 seems to be slower sometimes */
 	}
 	/* clear flags & end reset */
+	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
 	ACOMMAND(CFLAGScmd | RESETclear | CONFIGclear);
 
 	/* verify that the ARCnet signature byte is present */
+	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
 
 	com20020_copy_from_card(dev, 0, 0, &inbyte, 1);
+	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
 	if (inbyte != TESTvalue) {
+		BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
 		BUGMSG(D_NORMAL, "reset failed: TESTvalue not present.\n");
 		return 1;
 	}
 	/* enable extended (512-byte) packets */
 	ACOMMAND(CONFIGcmd | EXTconf);
+	BUGMSG(D_DEBUG, "%s: %d: %s\n",__FILE__,__LINE__,__FUNCTION__);
 
 	/* done!  return success. */
 	return 0;
@@ -270,22 +278,24 @@ static int com20020_reset(struct net_dev
 
 static void com20020_setmask(struct net_device *dev, int mask)
 {
-	short ioaddr = dev->base_addr;
+	u_int ioaddr = dev->base_addr;
+	BUGMSG(D_DURING, "Setting mask to %x at %x\n",mask,ioaddr);
 	AINTMASK(mask);
 }
 
 
 static void com20020_command(struct net_device *dev, int cmd)
 {
-	short ioaddr = dev->base_addr;
+	u_int ioaddr = dev->base_addr;
 	ACOMMAND(cmd);
 }
 
 
 static int com20020_status(struct net_device *dev)
 {
-	short ioaddr = dev->base_addr;
-	return ASTATUS();
+	u_int ioaddr = dev->base_addr;
+
+	return ASTATUS() + (ADIAGSTATUS()<<8);
 }
 
 static void com20020_close(struct net_device *dev)
diff -puN drivers/net/arcnet/com20020-isa.c~arcnet-fixes drivers/net/arcnet/com20020-isa.c
--- 25/drivers/net/arcnet/com20020-isa.c~arcnet-fixes	2004-11-21 22:42:30.235085808 -0800
+++ 25-akpm/drivers/net/arcnet/com20020-isa.c	2004-11-21 22:42:30.258082312 -0800
@@ -41,7 +41,6 @@
 
 #include <asm/io.h>
 
-
 #define VERSION "arcnet: COM20020 ISA support (by David Woodhouse et al.)\n"
 
 
diff -puN drivers/net/arcnet/Kconfig~arcnet-fixes drivers/net/arcnet/Kconfig
--- 25/drivers/net/arcnet/Kconfig~arcnet-fixes	2004-11-21 22:42:30.236085656 -0800
+++ 25-akpm/drivers/net/arcnet/Kconfig	2004-11-21 22:42:30.258082312 -0800
@@ -59,6 +59,25 @@ config ARCNET_RAW
 	  to work unless talking to a copy of the same Linux arcnet driver,
 	  but perhaps marginally faster in that case.
 
+config ARCNET_CAP
+	tristate "Enable CAP mode packet interface"
+	depends on ARCNET
+	help
+	  ARCnet "cap mode" packet encapsulation. Used to get the hardware
+          acknowledge back to userspace. After the initial protocol byte every
+          packet is stuffed with an extra 4 byte "cookie" which doesn't
+          actually appear on the network. After transmit the driver will send
+          back a packet with protocol byte 0 containing the status of the
+          transmition:
+             0=no hardware acknowledge
+             1=excessive nak
+             2=transmition accepted by the reciever hardware
+
+          Received packets are also stuffed with the extra 4 bytes but it will
+          be random data.
+
+          Cap only listens to protocol 1-8.
+
 config ARCNET_COM90xx
 	tristate "ARCnet COM90xx (normal) chipset driver"
 	depends on ARCNET
diff -puN drivers/net/arcnet/Makefile~arcnet-fixes drivers/net/arcnet/Makefile
--- 25/drivers/net/arcnet/Makefile~arcnet-fixes	2004-11-21 22:42:30.238085352 -0800
+++ 25-akpm/drivers/net/arcnet/Makefile	2004-11-21 22:42:30.258082312 -0800
@@ -5,6 +5,7 @@ obj-$(CONFIG_ARCNET) += arcnet.o
 obj-$(CONFIG_ARCNET_1201) += rfc1201.o
 obj-$(CONFIG_ARCNET_1051) += rfc1051.o
 obj-$(CONFIG_ARCNET_RAW) += arc-rawmode.o
+obj-$(CONFIG_ARCNET_CAP) += capmode.o
 obj-$(CONFIG_ARCNET_COM90xx) += com90xx.o
 obj-$(CONFIG_ARCNET_COM90xxIO) += com90io.o
 obj-$(CONFIG_ARCNET_RIM_I) += arc-rimi.o
diff -puN drivers/net/arcnet/rfc1051.c~arcnet-fixes drivers/net/arcnet/rfc1051.c
--- 25/drivers/net/arcnet/rfc1051.c~arcnet-fixes	2004-11-21 22:42:30.239085200 -0800
+++ 25-akpm/drivers/net/arcnet/rfc1051.c	2004-11-21 22:42:30.259082160 -0800
@@ -47,9 +47,12 @@ struct ArcProto rfc1051_proto =
 {
 	.suffix		= 's',
 	.mtu		= XMTU - RFC1051_HDR_SIZE,
+	.is_ip          = 1,
 	.rx		= rx,
 	.build_header	= build_header,
 	.prepare_tx	= prepare_tx,
+	.continue_tx    = NULL,
+	.ack_tx         = NULL
 };
 
 
diff -puN drivers/net/arcnet/rfc1201.c~arcnet-fixes drivers/net/arcnet/rfc1201.c
--- 25/drivers/net/arcnet/rfc1201.c~arcnet-fixes	2004-11-21 22:42:30.240085048 -0800
+++ 25-akpm/drivers/net/arcnet/rfc1201.c	2004-11-21 22:42:30.259082160 -0800
@@ -47,10 +47,12 @@ struct ArcProto rfc1201_proto =
 {
 	.suffix		= 'a',
 	.mtu		= 1500,	/* could be more, but some receivers can't handle it... */
+	.is_ip          = 1,    /* This is for sending IP and ARP packages */
 	.rx		= rx,
 	.build_header	= build_header,
 	.prepare_tx	= prepare_tx,
 	.continue_tx	= continue_tx,
+	.ack_tx         = NULL
 };
 
 
diff -puN include/linux/arcdevice.h~arcnet-fixes include/linux/arcdevice.h
--- 25/include/linux/arcdevice.h~arcnet-fixes	2004-11-21 22:42:30.242084744 -0800
+++ 25-akpm/include/linux/arcdevice.h	2004-11-21 22:42:30.260082008 -0800
@@ -25,7 +25,6 @@
 #define bool int
 #endif
 
-
 /*
  * RECON_THRESHOLD is the maximum number of RECON messages to receive
  * within one minute before printing a "cabling problem" warning. The
@@ -74,6 +73,7 @@
 #define D_SKB		1024	/* show skb's                             */
 #define D_SKB_SIZE	2048	/* show skb sizes			  */
 #define D_TIMING	4096	/* show time needed to copy buffers to card */
+#define D_DEBUG         8192    /* Very detailed debug line for line */
 
 #ifndef ARCNET_DEBUG_MAX
 #define ARCNET_DEBUG_MAX (127)	/* change to ~0 if you want detailed debugging */
@@ -135,6 +135,7 @@ extern int arcnet_debug;
 #define TXACKflag       0x02	/* transmitted msg. ackd */
 #define RECONflag       0x04	/* network reconfigured */
 #define TESTflag        0x08	/* test flag */
+#define EXCNAKflag      0x08    /* excesive nak flag */
 #define RESETflag       0x10	/* power-on-reset */
 #define RES1flag        0x20	/* reserved - usually set by jumper */
 #define RES2flag        0x40	/* reserved - usually set by jumper */
@@ -162,6 +163,8 @@ extern int arcnet_debug;
 #define RESETclear      0x08	/* power-on-reset */
 #define CONFIGclear     0x10	/* system reconfigured */
 
+#define EXCNAKclear     0x0E    /* Clear and acknowledge the excive nak bit */
+
 /* flags for "load test flags" command */
 #define TESTload        0x08	/* test flag (diagnostic) */
 
@@ -187,6 +190,7 @@ extern int arcnet_debug;
 struct ArcProto {
 	char suffix;		/* a for RFC1201, e for ether-encap, etc. */
 	int mtu;		/* largest possible packet */
+	int is_ip;              /* This is a ip plugin - not a raw thing */
 
 	void (*rx) (struct net_device * dev, int bufnum,
 		    struct archdr * pkthdr, int length);
@@ -197,9 +201,11 @@ struct ArcProto {
 	int (*prepare_tx) (struct net_device * dev, struct archdr * pkt, int length,
 			   int bufnum);
 	int (*continue_tx) (struct net_device * dev, int bufnum);
+	int (*ack_tx) (struct net_device * dev, int acked);
 };
 
-extern struct ArcProto *arc_proto_map[256], *arc_proto_default, *arc_bcast_proto;
+extern struct ArcProto *arc_proto_map[256], *arc_proto_default,
+	*arc_bcast_proto, *arc_raw_proto;
 extern struct ArcProto arc_proto_null;
 
 
@@ -251,6 +257,10 @@ struct arcnet_local {
 	char *card_name;	/* card ident string */
 	int card_flags;		/* special card features */
 
+
+	/* On preemtive and SMB a lock is needed */
+	spinlock_t lock;
+
 	/*
 	 * Buffer management: an ARCnet card has 4 x 512-byte buffers, each of
 	 * which can be used for either sending or receiving.  The new dynamic
@@ -279,6 +289,8 @@ struct arcnet_local {
 	int num_recons;		/* number of RECONs between first and last. */
 	bool network_down;	/* do we think the network is down? */
 
+	bool excnak_pending;    /* We just got an excesive nak interrupt */
+
 	struct {
 		uint16_t sequence;	/* sequence number (incs with each packet) */
 		uint16_t aborted_seq;
@@ -323,9 +335,10 @@ void arcnet_dump_skb(struct net_device *
 #endif
 
 #if (ARCNET_DEBUG_MAX & D_RX) || (ARCNET_DEBUG_MAX & D_TX)
-void arcnet_dump_packet(struct net_device *dev, int bufnum, char *desc);
+void arcnet_dump_packet(struct net_device *dev, int bufnum, char *desc,
+			int take_arcnet_lock);
 #else
-#define arcnet_dump_packet(dev, bufnum, desc) ;
+#define arcnet_dump_packet(dev, bufnum, desc,take_arcnet_lock) ;
 #endif
 
 void arcnet_unregister_proto(struct ArcProto *proto);
diff -puN include/linux/com20020.h~arcnet-fixes include/linux/com20020.h
--- 25/include/linux/com20020.h~arcnet-fixes	2004-11-21 22:42:30.243084592 -0800
+++ 25-akpm/include/linux/com20020.h	2004-11-21 22:42:30.261081856 -0800
@@ -34,17 +34,24 @@ int com20020_found(struct net_device *de
 #define ARCNET_TOTAL_SIZE 8
 
 /* various register addresses */
-#define _INTMASK  (ioaddr+0)	/* writable */
-#define _STATUS   (ioaddr+0)	/* readable */
-#define _COMMAND  (ioaddr+1)	/* standard arcnet commands */
-#define _DIAGSTAT (ioaddr+1)	/* diagnostic status register */
-#define _ADDR_HI  (ioaddr+2)	/* control registers for IO-mapped memory */
-#define _ADDR_LO  (ioaddr+3)
-#define _MEMDATA  (ioaddr+4)	/* data port for IO-mapped memory */
-#define _SUBADR   (ioaddr+5)	/* the extended port _XREG refers to */
-#define _CONFIG   (ioaddr+6)	/* configuration register */
-#define _XREG     (ioaddr+7)	/* extra registers (indexed by _CONFIG 
-					or _SUBADR) */
+#ifdef CONFIG_SA1100_CT6001
+#define BUS_ALIGN  2  /* 8 bit device on a 16 bit bus - needs padding */
+#else
+#define BUS_ALIGN  1
+#endif
+
+
+#define _INTMASK  (ioaddr+BUS_ALIGN*0)	/* writable */
+#define _STATUS   (ioaddr+BUS_ALIGN*0)	/* readable */
+#define _COMMAND  (ioaddr+BUS_ALIGN*1)	/* standard arcnet commands */
+#define _DIAGSTAT (ioaddr+BUS_ALIGN*1)	/* diagnostic status register */
+#define _ADDR_HI  (ioaddr+BUS_ALIGN*2)	/* control registers for IO-mapped memory */
+#define _ADDR_LO  (ioaddr+BUS_ALIGN*3)
+#define _MEMDATA  (ioaddr+BUS_ALIGN*4)	/* data port for IO-mapped memory */
+#define _SUBADR   (ioaddr+BUS_ALIGN*5)	/* the extended port _XREG refers to */
+#define _CONFIG   (ioaddr+BUS_ALIGN*6)	/* configuration register */
+#define _XREG     (ioaddr+BUS_ALIGN*7)	/* extra registers (indexed by _CONFIG
+  					or _SUBADR) */
 
 /* in the ADDR_HI register */
 #define RDDATAflag	0x80	/* next access is a read (not a write) */
@@ -99,6 +106,7 @@ int com20020_found(struct net_device *de
                   }
 
 #define ASTATUS()	inb(_STATUS)
+#define ADIAGSTATUS()	inb(_DIAGSTAT)
 #define ACOMMAND(cmd)	outb((cmd),_COMMAND)
 #define AINTMASK(msk)	outb((msk),_INTMASK)
 
diff -puN include/linux/if_arcnet.h~arcnet-fixes include/linux/if_arcnet.h
--- 25/include/linux/if_arcnet.h~arcnet-fixes	2004-11-21 22:42:30.245084288 -0800
+++ 25-akpm/include/linux/if_arcnet.h	2004-11-21 22:42:30.261081856 -0800
@@ -23,6 +23,9 @@
  *    These are the defined ARCnet Protocol ID's.
  */
 
+/* CAP mode */
+/* No macro but uses 1-8 */
+
 /* RFC1201 Protocol ID's */
 #define ARC_P_IP		212	/* 0xD4 */
 #define ARC_P_IPV6		196	/* 0xC4: RFC2497 */
@@ -86,6 +89,16 @@ struct arc_eth_encap
 #define ETH_ENCAP_HDR_SIZE 14
 
 
+struct arc_cap
+{
+	uint8_t proto;
+	uint8_t cookie[sizeof(int)];   /* Actually NOT sent over the network */
+	union {
+		uint8_t ack;
+		uint8_t raw[0];		/* 507 bytes */
+	} mes;
+};
+
 /*
  * The data needed by the actual arcnet hardware.
  *
@@ -116,6 +129,7 @@ struct archdr
 	struct arc_rfc1201   rfc1201;
 	struct arc_rfc1051   rfc1051;
 	struct arc_eth_encap eth_encap;
+	struct arc_cap       cap;
 	uint8_t raw[0];		/* 508 bytes				*/
     } soft;
 };
diff -puN include/linux/if_ether.h~arcnet-fixes include/linux/if_ether.h
--- 25/include/linux/if_ether.h~arcnet-fixes	2004-11-21 22:42:30.246084136 -0800
+++ 25-akpm/include/linux/if_ether.h	2004-11-21 22:42:30.262081704 -0800
@@ -91,6 +91,7 @@
 #define ETH_P_IRDA	0x0017		/* Linux-IrDA			*/
 #define ETH_P_ECONET	0x0018		/* Acorn Econet			*/
 #define ETH_P_HDLC	0x0019		/* HDLC frames			*/
+#define ETH_P_ARCNET	0x001A		/* 1A for ArcNet :-)            */
 
 /*
  *	This is an Ethernet frame header.
diff -puN include/linux/net.h~arcnet-fixes include/linux/net.h
_