ISDN: Make the state machine explicit

Add a finite state machine helper module, which is basically copied over
from the hisax driver with a little bit of beautification.

Eventually, all ISDN should be converted to using these routines.

drivers/isdn/i4l/Makefile

@@ -12,6 +12,7 @@ obj-$(CONFIG_ISDN_PPP_BSDCOMP)		+= isdn_bsdcomp.o
 # Multipart objects.
 
 isdn-objs				:= isdn_net.o isdn_net_lib.o \
+					   isdn_fsm.o \
 					   isdn_ciscohdlck.o \
 					   isdn_tty.o isdn_v110.o \
 					   isdn_common.o \

drivers/isdn/i4l/isdn_fsm.c

+/* $Id: fsm.c,v 1.14.6.4 2001/09/23 22:24:47 kai Exp $
+ *
+ * Finite state machine
+ *
+ * Author       Karsten Keil
+ * Copyright    by Karsten Keil      <keil@isdn4linux.de>
+ *              by Kai Germaschewski <kai.germaschewski@gmx.de>
+ * 
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ * Thanks to    Jan den Ouden
+ *              Fritz Elfert
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include "isdn_fsm.h"
+
+int
+fsm_new(struct fsm *fsm)
+{
+	int i;
+	int size = sizeof(fsm_fn) * fsm->st_cnt * fsm->ev_cnt;
+
+	fsm->jumpmatrix = kmalloc(size, GFP_KERNEL);
+	if (!fsm->jumpmatrix)
+		return -ENOMEM;
+
+	memset(fsm->jumpmatrix, 0, size);
+
+	for (i = 0; i < fsm->fn_cnt; i++) {
+		if (fsm->fn_tbl[i].st >= fsm->st_cnt || 
+		    fsm->fn_tbl[i].ev >= fsm->ev_cnt) {
+			printk(KERN_ERR "FsmNew Error line %d st(%d/%d) ev(%d/%d)\n", i,
+			       fsm->fn_tbl[i].st, fsm->st_cnt, 
+			       fsm->fn_tbl[i].ev, fsm->ev_cnt);
+			continue;
+		}
+		fsm->jumpmatrix[fsm->st_cnt * fsm->fn_tbl[i].ev + fsm->fn_tbl[i].st] = fsm->fn_tbl[i].routine;
+	}
+	return 0;
+}
+
+void
+fsm_free(struct fsm *fsm)
+{
+	kfree(fsm->jumpmatrix);
+}
+
+int
+fsm_event(struct fsm_inst *fi, int event, void *arg)
+{
+	fsm_fn fn;
+
+	if (fi->state >= fi->fsm->st_cnt || 
+	    event >= fi->fsm->ev_cnt) {
+		printk(KERN_ERR "FsmEvent Error st(%d/%d) ev(%d/%d)\n",
+		       fi->state, fi->fsm->st_cnt,event, 
+		       fi->fsm->ev_cnt);
+		return -EINVAL;
+	}
+	fn = fi->fsm->jumpmatrix[fi->fsm->st_cnt * event + fi->state];
+	if (!fn) {
+		if (fi->debug)
+			fi->printdebug(fi, "State %s Event %s no routine",
+				       fi->fsm->st_str[fi->state],
+				       fi->fsm->ev_str[event]);
+		return -ESRCH;
+	}
+	if (fi->debug)
+		fi->printdebug(fi, "State %s Event %s",
+			       fi->fsm->st_str[fi->state],
+			       fi->fsm->ev_str[event]);
+
+	fn(fi, event, arg);
+	return 0;
+}
+
+void
+fsm_change_state(struct fsm_inst *fi, int newstate)
+{
+	fi->state = newstate;
+	if (fi->debug)
+		fi->printdebug(fi, "ChangeState %s",
+			       fi->fsm->st_str[newstate]);
+}
+
+#if 0
+static void
+FsmExpireTimer(struct FsmTimer *ft)
+{
+#if FSM_TIMER_DEBUG
+	if (ft->fi->debug)
+		ft->fi->printdebug(ft->fi, "FsmExpireTimer %lx", (long) ft);
+#endif
+	FsmEvent(ft->fi, ft->event, ft->arg);
+}
+
+void
+FsmInitTimer(struct FsmInst *fi, struct FsmTimer *ft)
+{
+	ft->fi = fi;
+	ft->tl.function = (void *) FsmExpireTimer;
+	ft->tl.data = (long) ft;
+#if FSM_TIMER_DEBUG
+	if (ft->fi->debug)
+		ft->fi->printdebug(ft->fi, "FsmInitTimer %lx", (long) ft);
+#endif
+	init_timer(&ft->tl);
+}
+
+void
+FsmDelTimer(struct FsmTimer *ft, int where)
+{
+#if FSM_TIMER_DEBUG
+	if (ft->fi->debug)
+		ft->fi->printdebug(ft->fi, "FsmDelTimer %lx %d", (long) ft, where);
+#endif
+	del_timer(&ft->tl);
+}
+
+int
+FsmAddTimer(struct FsmTimer *ft,
+	    int millisec, int event, void *arg, int where)
+{
+
+#if FSM_TIMER_DEBUG
+	if (ft->fi->debug)
+		ft->fi->printdebug(ft->fi, "FsmAddTimer %lx %d %d",
+			(long) ft, millisec, where);
+#endif
+
+	if (timer_pending(&ft->tl)) {
+		printk(KERN_WARNING "FsmAddTimer: timer already active!\n");
+		ft->fi->printdebug(ft->fi, "FsmAddTimer already active!");
+		return -1;
+	}
+	init_timer(&ft->tl);
+	ft->event = event;
+	ft->arg = arg;
+	ft->tl.expires = jiffies + (millisec * HZ) / 1000;
+	add_timer(&ft->tl);
+	return 0;
+}
+
+void
+FsmRestartTimer(struct FsmTimer *ft,
+	    int millisec, int event, void *arg, int where)
+{
+
+#if FSM_TIMER_DEBUG
+	if (ft->fi->debug)
+		ft->fi->printdebug(ft->fi, "FsmRestartTimer %lx %d %d",
+			(long) ft, millisec, where);
+#endif
+
+	if (timer_pending(&ft->tl))
+		del_timer(&ft->tl);
+	init_timer(&ft->tl);
+	ft->event = event;
+	ft->arg = arg;
+	ft->tl.expires = jiffies + (millisec * HZ) / 1000;
+	add_timer(&ft->tl);
+}
+#endif

drivers/isdn/i4l/isdn_fsm.h

+/* $Id: fsm.h,v 1.3.2.2 2001/09/23 22:24:47 kai Exp $
+ *
+ * Finite state machine
+ *
+ * Author       Karsten Keil
+ * Copyright    by Karsten Keil      <keil@isdn4linux.de>
+ *              by Kai Germaschewski <kai.germaschewski@gmx.de>
+ * 
+ * This software may be used and distributed according to the terms
+ * of the GNU General Public License, incorporated herein by reference.
+ *
+ */
+
+#ifndef __FSM_H__
+#define __FSM_H__
+
+#include <linux/timer.h>
+
+struct fsm_inst;
+
+typedef void (*fsm_fn)(struct fsm_inst *, int, void *);
+
+struct fsm {
+	fsm_fn *jumpmatrix;
+	int st_cnt, ev_cnt, fn_cnt;
+	char **st_str, **ev_str;
+	struct fsm_node *fn_tbl;
+};
+
+struct fsm_inst {
+	struct fsm *fsm;
+	int state;
+	int debug;
+	void *userdata;
+	int userint;
+	void (*printdebug) (struct fsm_inst *, char *, ...);
+};
+
+struct fsm_node {
+	int st, ev;
+	void (*routine) (struct fsm_inst *, int, void *);
+};
+
+struct fsm_timer {
+	struct fsm_inst *fi;
+	struct timer_list tl;
+	int ev;
+	void *arg;
+};
+
+int  fsm_new(struct fsm *fsm);
+void fsm_free(struct fsm *fsm);
+int  fsm_event(struct fsm_inst *fi, int event, void *arg);
+void fsm_change_state(struct fsm_inst *fi, int newstate);
+void fsm_init_timer(struct fsm_inst *fi, struct fsm_timer *ft);
+int  fsm_add_timer(struct fsm_timer *ft, int timeout, int event);
+void fsm_mod_timer(struct fsm_timer *ft, int timeout, int event);
+void fsm_del_timer(struct fsm_timer *ft);
+
+#endif

drivers/isdn/i4l/isdn_net.c

@@ -163,25 +163,6 @@ isdn_net_unreachable(struct net_device *dev, struct sk_buff *skb, char *reason)
 	dst_link_failure(skb);
 }
 
-/*
- * Handle status-messages from ISDN-interfacecard.
- * This function is called from within the main-status-dispatcher
- * isdn_status_callback, which itself is called from the low-level driver.
- * Return: 1 = Event handled, 0 = not for us or unknown Event.
- */
-int
-isdn_net_stat_callback(int idx, isdn_ctrl *c)
-{
-	isdn_net_dev *idev = isdn_slot_idev(idx);
-
-	if (!idev) {
-		HERE;
-		return 0;
-	}
-
-	return isdn_net_handle_event(idev, c->command, c);
-}
-
 static void
 isdn_net_log_skb(struct sk_buff *skb, isdn_net_dev *idev)
 {
@@ -510,7 +491,7 @@ isdn_net_find_icall(int di, int ch, int idx, setup_parm *setup)
 
                 /* check acceptable call types for DOV */
 		dbg_net_icall("n_fi: if='%s', l.msn=%s, l.flags=%#x, l.dstate=%d\n",
-			      idev->name, mlp->msn, mlp->flags, idev->dialstate);
+			      idev->name, mlp->msn, mlp->flags, idev->fi.state);
 
                 my_eaz = isdn_slot_map_eaz2msn(slot, mlp->msn);
                 if (si1 == 1) { /* it's a DOV call, check if we allow it */
@@ -768,4 +749,7 @@ isdn_net_init(void)
 #ifdef CONFIG_ISDN_PPP
 	register_isdn_netif(ISDN_NET_ENCAP_SYNCPPP,    &isdn_ppp_ops);
 #endif
+
+	isdn_net_lib_init();
 }
+

drivers/isdn/i4l/isdn_net.h

@@ -34,6 +34,8 @@
 
 extern void isdn_net_init(void);
 extern void isdn_net_exit(void);
+extern void isdn_net_lib_init(void);
+extern void isdn_net_lib_exit(void);
 extern void isdn_net_hangup_all(void);
 extern int isdn_net_ioctl(struct inode *, struct file *, uint, ulong);
 

include/linux/isdn.h

@@ -16,6 +16,9 @@
 
 #include <linux/ioctl.h>
 
+// FIXME!!!
+#include <../drivers/isdn/i4l/isdn_fsm.h>
+
 #ifdef CONFIG_COBALT_MICRO_SERVER
 /* Save memory */
 #define ISDN_MAX_DRIVERS    2
@@ -367,8 +370,8 @@ typedef struct isdn_net_dev_s {
   int                    exclusive;    /* -1 if non excl./idx to excl chan */
 
   struct timer_list      dial_timer;   /* dial events timer                */
+  struct fsm_inst        fi;           /* call control state machine       */
   int                    dial_event;   /* event in case of timer expiry    */
-  int                    dialstate;    /* State for dialing                */
   int                    dial;         /* # of phone number just dialed    */
   int                    outgoing;     /* Flag: outgoing call              */
   int                    dialretry;    /* Counter for Dialout-retries      */