[PATCH] 2.6 Generic HDLC update

The attached patch updates generic HDLC:
- fixed some carrier-related problems (Cisco HDLC and FR links could
  report valid link when no carrier was detected at startup).
- fixed kbuild problems with wanxl firmware (building kernel in separate
  tree). $(src)/wanxlfw.inc is now wanxlfw.inc_shipped.

drivers/net/wan/Makefile

@@ -61,6 +61,9 @@ obj-$(CONFIG_C101)		+= c101.o
 obj-$(CONFIG_WANXL)		+= wanxl.o
 obj-$(CONFIG_PCI200SYN)		+= pci200syn.o
 
+clean-files := wanxlfw.inc
+$(obj)/wanxl.o:	$(obj)/wanxlfw.inc
+
 ifeq ($(CONFIG_WANXL_BUILD_FIRMWARE),y)
 ifeq ($(ARCH),m68k)
   AS68K = $(AS)
@@ -72,12 +75,12 @@ endif
 
 quiet_cmd_build_wanxlfw = BLD FW  $@
       cmd_build_wanxlfw = \
-	$(CPP) -Wp,-MD,$(depfile) -Iinclude $(obj)/wanxlfw.S | $(AS68K) -m68360 -o $(obj)/wanxlfw.o; \
+	$(CPP) -Wp,-MD,$(depfile) -I$(srctree)/include $< | $(AS68K) -m68360 -o $(obj)/wanxlfw.o; \
 	$(LD68K) --oformat binary -Ttext 0x1000 $(obj)/wanxlfw.o -o $(obj)/wanxlfw.bin; \
 	hexdump -ve '"\n" 16/1 "0x%02X,"' $(obj)/wanxlfw.bin | sed 's/0x  ,//g;1s/^/static u8 firmware[]={/;$$s/,$$/\n};\n/' >$(obj)/wanxlfw.inc; \
 	rm -f $(obj)/wanxlfw.bin $(obj)/wanxlfw.o
 
-$(obj)/wanxlfw.inc:	$(obj)/wanxlfw.S
+$(obj)/wanxlfw.inc:	$(src)/wanxlfw.S
 	$(call if_changed_dep,build_wanxlfw)
 targets += wanxlfw.inc
 endif

drivers/net/wan/c101.c

@@ -379,8 +379,6 @@ static int __init c101_run(unsigned long irq, unsigned long winbase)
 		return result;
 	}
 
-	/* XXX: are we OK with having that done when card is already up? */
-
 	sca_init_sync_port(card); /* Set up C101 memory */
 	hdlc_set_carrier(!(sca_in(MSCI1_OFFSET + ST3, card) & ST3_DCD), dev);
 

drivers/net/wan/hdlc_cisco.c

@@ -180,7 +180,8 @@ static int cisco_rx(struct sk_buff *skb)
 
 		case CISCO_KEEPALIVE_REQ:
 			hdlc->state.cisco.rxseq = ntohl(cisco_data->par1);
-			if (ntohl(cisco_data->par2)==hdlc->state.cisco.txseq) {
+			if (hdlc->state.cisco.request_sent &&
+			    ntohl(cisco_data->par2)==hdlc->state.cisco.txseq) {
 				hdlc->state.cisco.last_poll = jiffies;
 				if (!hdlc->state.cisco.up) {
 					u32 sec, min, hrs, days;
@@ -192,9 +193,10 @@ static int cisco_rx(struct sk_buff *skb)
 					       "uptime %ud%uh%um%us)\n",
 					       dev->name, days, hrs,
 					       min, sec);
-				}
+					netif_carrier_on(dev);
 					hdlc->state.cisco.up = 1;
 				}
+			}
 
 			dev_kfree_skb_any(skb);
 			return NET_RX_SUCCESS;
@@ -219,17 +221,18 @@ static void cisco_timer(unsigned long arg)
 	struct net_device *dev = (struct net_device *)arg;
 	hdlc_device *hdlc = dev_to_hdlc(dev);
 
-	if (hdlc->state.cisco.up && jiffies - hdlc->state.cisco.last_poll >=
-	    hdlc->state.cisco.settings.timeout * HZ) {
+	if (hdlc->state.cisco.up &&
+	    time_after(jiffies, hdlc->state.cisco.last_poll +
+		       hdlc->state.cisco.settings.timeout * HZ)) {
 		hdlc->state.cisco.up = 0;
 		printk(KERN_INFO "%s: Link down\n", dev->name);
-		if (netif_carrier_ok(dev))
 		netif_carrier_off(dev);
 	}
 
 	cisco_keepalive_send(dev, CISCO_KEEPALIVE_REQ,
 			     ++hdlc->state.cisco.txseq,
 			     hdlc->state.cisco.rxseq);
+	hdlc->state.cisco.request_sent = 1;
 	hdlc->state.cisco.timer.expires = jiffies +
 		hdlc->state.cisco.settings.interval * HZ;
 	hdlc->state.cisco.timer.function = cisco_timer;
@@ -242,8 +245,8 @@ static void cisco_timer(unsigned long arg)
 static void cisco_start(struct net_device *dev)
 {
 	hdlc_device *hdlc = dev_to_hdlc(dev);
-	hdlc->state.cisco.last_poll = 0;
 	hdlc->state.cisco.up = 0;
+	hdlc->state.cisco.request_sent = 0;
 	hdlc->state.cisco.txseq = hdlc->state.cisco.rxseq = 0;
 
 	init_timer(&hdlc->state.cisco.timer);
@@ -257,9 +260,12 @@ static void cisco_start(struct net_device *dev)
 
 static void cisco_stop(struct net_device *dev)
 {
-	del_timer_sync(&dev_to_hdlc(dev)->state.cisco.timer);
+	hdlc_device *hdlc = dev_to_hdlc(dev);
+	del_timer_sync(&hdlc->state.cisco.timer);
 	if (netif_carrier_ok(dev))
 		netif_carrier_off(dev);
+	hdlc->state.cisco.up = 0;
+	hdlc->state.cisco.request_sent = 0;
 }
 
 

drivers/net/wan/hdlc_fr.c

@@ -584,7 +584,8 @@ static void fr_timer(unsigned long arg)
 	u32 list;
 
 	if (hdlc->state.fr.settings.dce)
-		reliable = (jiffies - hdlc->state.fr.last_poll <
+		reliable = hdlc->state.fr.request &&
+			time_before(jiffies, hdlc->state.fr.last_poll +
 				    hdlc->state.fr.settings.t392 * HZ);
 	else {
 		hdlc->state.fr.last_errors <<= 1; /* Shift the list */
@@ -617,6 +618,7 @@ static void fr_timer(unsigned long arg)
 
 		fr_lmi_send(dev, hdlc->state.fr.n391cnt == 0);
 
+		hdlc->state.fr.last_poll = jiffies;
 		hdlc->state.fr.request = 1;
 		hdlc->state.fr.timer.expires = jiffies +
 			hdlc->state.fr.settings.t391 * HZ;
@@ -689,6 +691,7 @@ static int fr_lmi_recv(struct net_device *dev, struct sk_buff *skb)
 			       dev->name, reptype);
 			return 1;
 		}
+		hdlc->state.fr.last_poll = jiffies;
 	}
 
 	error = 0;
@@ -728,7 +731,12 @@ static int fr_lmi_recv(struct net_device *dev, struct sk_buff *skb)
 
 	/* DTE */
 
-	if (reptype != LMI_FULLREP || error)
+	hdlc->state.fr.request = 0; /* got response, no request pending */
+
+	if (error)
+		return 0;
+
+	if (reptype != LMI_FULLREP)
 		return 0;
 
 	stat_len = 3;
@@ -829,9 +837,6 @@ static int fr_rx(struct sk_buff *skb)
 			if (fr_lmi_recv(ndev, skb))
 				goto rx_error;
 			else {
-				/* No request pending */
-				hdlc->state.fr.request = 0;
-				hdlc->state.fr.last_poll = jiffies;
 				dev_kfree_skb_any(skb);
 				return NET_RX_SUCCESS;
 			}
@@ -946,9 +951,6 @@ static void fr_start(struct net_device *dev)
 	printk(KERN_DEBUG "fr_start\n");
 #endif
 	if (hdlc->state.fr.settings.lmi != LMI_NONE) {
-		if (netif_carrier_ok(dev))
-			netif_carrier_off(dev);
-		hdlc->state.fr.last_poll = 0;
 		hdlc->state.fr.reliable = 0;
 		hdlc->state.fr.dce_changed = 1;
 		hdlc->state.fr.request = 0;

drivers/net/wan/hdlc_generic.c

@@ -15,6 +15,11 @@
  *	* X.25
  *
  * Use sethdlc utility to set line parameters, protocol and PVCs
+ *
+ * How does it work:
+ * - proto.open(), close(), start(), stop() calls are serialized.
+ *   The order is: open, [ start, stop ... ] close ...
+ * - proto.start() and stop() are called with spin_lock_irq held.
  */
 
 #include <linux/config.h>
@@ -33,7 +38,7 @@
 #include <linux/hdlc.h>
 
 
-static const char* version = "HDLC support module revision 1.16";
+static const char* version = "HDLC support module revision 1.17";
 
 #undef DEBUG_LINK
 
@@ -69,51 +74,75 @@ static int hdlc_rcv(struct sk_buff *skb, struct net_device *dev,
 
 
 
+static void __hdlc_set_carrier_on(struct net_device *dev)
+{
+	hdlc_device *hdlc = dev_to_hdlc(dev);
+	if (hdlc->proto.start)
+		return hdlc->proto.start(dev);
+#ifdef DEBUG_LINK
+	if (netif_carrier_ok(dev))
+		printk(KERN_ERR "hdlc_set_carrier_on(): already on\n");
+#endif
+	netif_carrier_on(dev);
+}
+
+
+
+static void __hdlc_set_carrier_off(struct net_device *dev)
+{
+	hdlc_device *hdlc = dev_to_hdlc(dev);
+	if (hdlc->proto.stop)
+		return hdlc->proto.stop(dev);
+
+#ifdef DEBUG_LINK
+	if (!netif_carrier_ok(dev))
+		printk(KERN_ERR "hdlc_set_carrier_off(): already off\n");
+#endif
+	netif_carrier_off(dev);
+}
+
+
+
 void hdlc_set_carrier(int on, struct net_device *dev)
 {
 	hdlc_device *hdlc = dev_to_hdlc(dev);
+	unsigned long flags;
 	on = on ? 1 : 0;
 
 #ifdef DEBUG_LINK
 	printk(KERN_DEBUG "hdlc_set_carrier %i\n", on);
 #endif
 
-	spin_lock_irq(&hdlc->state_lock);
+	spin_lock_irqsave(&hdlc->state_lock, flags);
 
 	if (hdlc->carrier == on)
 		goto carrier_exit; /* no change in DCD line level */
 
-	printk(KERN_INFO "%s: carrier %s\n", dev->name,
-	       on ? "ON" : "off");
+#ifdef DEBUG_LINK
+	printk(KERN_INFO "%s: carrier %s\n", dev->name, on ? "ON" : "off");
+#endif
 	hdlc->carrier = on;
 
 	if (!hdlc->open)
 		goto carrier_exit;
 
-	if (hdlc->carrier) {
-		if (hdlc->proto.start)
-			hdlc->proto.start(dev);
-		else if (!netif_carrier_ok(dev))
-			netif_carrier_on(dev);
+	if (hdlc->carrier)
+		__hdlc_set_carrier_on(dev);
+	else
+		__hdlc_set_carrier_off(dev);
 
-	} else { /* no carrier */
-		if (hdlc->proto.stop)
-			hdlc->proto.stop(dev);
-		else if (netif_carrier_ok(dev))
-			netif_carrier_off(dev);
-	}
-
- carrier_exit:
-	spin_unlock_irq(&hdlc->state_lock);
+carrier_exit:
+	spin_unlock_irqrestore(&hdlc->state_lock, flags);
 }
 
 
+
 /* Must be called by hardware driver when HDLC device is being opened */
 int hdlc_open(struct net_device *dev)
 {
 	hdlc_device *hdlc = dev_to_hdlc(dev);
 #ifdef DEBUG_LINK
-	printk(KERN_DEBUG "hdlc_open carrier %i open %i\n",
+	printk(KERN_DEBUG "hdlc_open() carrier %i open %i\n",
 	       hdlc->carrier, hdlc->open);
 #endif
 
@@ -128,14 +157,8 @@ int hdlc_open(struct net_device *dev)
 
 	spin_lock_irq(&hdlc->state_lock);
 
-	if (hdlc->carrier) {
-		if (hdlc->proto.start)
-			hdlc->proto.start(dev);
-		else if (!netif_carrier_ok(dev))
-			netif_carrier_on(dev);
-
-	} else if (netif_carrier_ok(dev))
-		netif_carrier_off(dev);
+	if (hdlc->carrier)
+		__hdlc_set_carrier_on(dev);
 
 	hdlc->open = 1;
 
@@ -150,15 +173,15 @@ void hdlc_close(struct net_device *dev)
 {
 	hdlc_device *hdlc = dev_to_hdlc(dev);
 #ifdef DEBUG_LINK
-	printk(KERN_DEBUG "hdlc_close carrier %i open %i\n",
+	printk(KERN_DEBUG "hdlc_close() carrier %i open %i\n",
 	       hdlc->carrier, hdlc->open);
 #endif
 
 	spin_lock_irq(&hdlc->state_lock);
 
 	hdlc->open = 0;
-	if (hdlc->carrier && hdlc->proto.stop)
-		hdlc->proto.stop(dev);
+	if (hdlc->carrier)
+		__hdlc_set_carrier_off(dev);
 
 	spin_unlock_irq(&hdlc->state_lock);
 
@@ -257,25 +280,7 @@ struct net_device *alloc_hdlcdev(void *priv)
 
 int register_hdlc_device(struct net_device *dev)
 {
-	int result;
-	hdlc_device *hdlc = dev_to_hdlc(dev);
-
-	dev->get_stats = hdlc_get_stats;
-	dev->change_mtu = hdlc_change_mtu;
-	dev->mtu = HDLC_MAX_MTU;
-
-	dev->type = ARPHRD_RAWHDLC;
-	dev->hard_header_len = 16;
-
-	dev->flags = IFF_POINTOPOINT | IFF_NOARP;
-
-	hdlc->proto.id = -1;
-	hdlc->proto.detach = NULL;
-	hdlc->carrier = 1;
-	hdlc->open = 0;
-	spin_lock_init(&hdlc->state_lock);
-
-	result = dev_alloc_name(dev, "hdlc%d");
+	int result = dev_alloc_name(dev, "hdlc%d");
 	if (result < 0)
 		return result;
 
@@ -283,6 +288,9 @@ int register_hdlc_device(struct net_device *dev)
 	if (result != 0)
 		return -EIO;
 
+	if (netif_carrier_ok(dev))
+		netif_carrier_off(dev); /* no carrier until DCD goes up */
+
 	return 0;
 }
 

include/linux/hdlc.h

@@ -134,7 +134,7 @@ typedef struct hdlc_device_struct {
 			int dce_pvc_count;
 
 			struct timer_list timer;
-			int last_poll;
+			unsigned long last_poll;
 			int reliable;
 			int dce_changed;
 			int request;
@@ -149,8 +149,9 @@ typedef struct hdlc_device_struct {
 			cisco_proto settings;
 
 			struct timer_list timer;
-			int last_poll;
+			unsigned long last_poll;
 			int up;
+			int request_sent;
 			u32 txseq; /* TX sequence number */
 			u32 rxseq; /* RX sequence number */
 		}cisco;