1 /*
2  * finite state machine implementation
3  *
4  * Author       Karsten Keil <kkeil@novell.com>
5  *
6  * Thanks to    Jan den Ouden
7  *              Fritz Elfert
8  * Copyright 2008  by Karsten Keil <kkeil@novell.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  */
20 
21 #include <linux/kernel.h>
22 #include <linux/slab.h>
23 #include <linux/module.h>
24 #include <linux/string.h>
25 #include "fsm.h"
26 
27 #define FSM_TIMER_DEBUG 0
28 
29 void
mISDN_FsmNew(struct Fsm * fsm,struct FsmNode * fnlist,int fncount)30 mISDN_FsmNew(struct Fsm *fsm,
31 	     struct FsmNode *fnlist, int fncount)
32 {
33 	int i;
34 
35 	fsm->jumpmatrix = kzalloc(sizeof(FSMFNPTR) * fsm->state_count *
36 				  fsm->event_count, GFP_KERNEL);
37 
38 	for (i = 0; i < fncount; i++)
39 		if ((fnlist[i].state >= fsm->state_count) ||
40 		    (fnlist[i].event >= fsm->event_count)) {
41 			printk(KERN_ERR
42 			       "mISDN_FsmNew Error: %d st(%ld/%ld) ev(%ld/%ld)\n",
43 			       i, (long)fnlist[i].state, (long)fsm->state_count,
44 			       (long)fnlist[i].event, (long)fsm->event_count);
45 		} else
46 			fsm->jumpmatrix[fsm->state_count * fnlist[i].event +
47 					fnlist[i].state] = (FSMFNPTR) fnlist[i].routine;
48 }
49 EXPORT_SYMBOL(mISDN_FsmNew);
50 
51 void
mISDN_FsmFree(struct Fsm * fsm)52 mISDN_FsmFree(struct Fsm *fsm)
53 {
54 	kfree((void *) fsm->jumpmatrix);
55 }
56 EXPORT_SYMBOL(mISDN_FsmFree);
57 
58 int
mISDN_FsmEvent(struct FsmInst * fi,int event,void * arg)59 mISDN_FsmEvent(struct FsmInst *fi, int event, void *arg)
60 {
61 	FSMFNPTR r;
62 
63 	if ((fi->state >= fi->fsm->state_count) ||
64 	    (event >= fi->fsm->event_count)) {
65 		printk(KERN_ERR
66 		       "mISDN_FsmEvent Error st(%ld/%ld) ev(%d/%ld)\n",
67 		       (long)fi->state, (long)fi->fsm->state_count, event,
68 		       (long)fi->fsm->event_count);
69 		return 1;
70 	}
71 	r = fi->fsm->jumpmatrix[fi->fsm->state_count * event + fi->state];
72 	if (r) {
73 		if (fi->debug)
74 			fi->printdebug(fi, "State %s Event %s",
75 				       fi->fsm->strState[fi->state],
76 				       fi->fsm->strEvent[event]);
77 		r(fi, event, arg);
78 		return 0;
79 	} else {
80 		if (fi->debug)
81 			fi->printdebug(fi, "State %s Event %s no action",
82 				       fi->fsm->strState[fi->state],
83 				       fi->fsm->strEvent[event]);
84 		return 1;
85 	}
86 }
87 EXPORT_SYMBOL(mISDN_FsmEvent);
88 
89 void
mISDN_FsmChangeState(struct FsmInst * fi,int newstate)90 mISDN_FsmChangeState(struct FsmInst *fi, int newstate)
91 {
92 	fi->state = newstate;
93 	if (fi->debug)
94 		fi->printdebug(fi, "ChangeState %s",
95 			       fi->fsm->strState[newstate]);
96 }
97 EXPORT_SYMBOL(mISDN_FsmChangeState);
98 
99 static void
FsmExpireTimer(struct FsmTimer * ft)100 FsmExpireTimer(struct FsmTimer *ft)
101 {
102 #if FSM_TIMER_DEBUG
103 	if (ft->fi->debug)
104 		ft->fi->printdebug(ft->fi, "FsmExpireTimer %lx", (long) ft);
105 #endif
106 	mISDN_FsmEvent(ft->fi, ft->event, ft->arg);
107 }
108 
109 void
mISDN_FsmInitTimer(struct FsmInst * fi,struct FsmTimer * ft)110 mISDN_FsmInitTimer(struct FsmInst *fi, struct FsmTimer *ft)
111 {
112 	ft->fi = fi;
113 	ft->tl.function = (void *) FsmExpireTimer;
114 	ft->tl.data = (long) ft;
115 #if FSM_TIMER_DEBUG
116 	if (ft->fi->debug)
117 		ft->fi->printdebug(ft->fi, "mISDN_FsmInitTimer %lx", (long) ft);
118 #endif
119 	init_timer(&ft->tl);
120 }
121 EXPORT_SYMBOL(mISDN_FsmInitTimer);
122 
123 void
mISDN_FsmDelTimer(struct FsmTimer * ft,int where)124 mISDN_FsmDelTimer(struct FsmTimer *ft, int where)
125 {
126 #if FSM_TIMER_DEBUG
127 	if (ft->fi->debug)
128 		ft->fi->printdebug(ft->fi, "mISDN_FsmDelTimer %lx %d",
129 				   (long) ft, where);
130 #endif
131 	del_timer(&ft->tl);
132 }
133 EXPORT_SYMBOL(mISDN_FsmDelTimer);
134 
135 int
mISDN_FsmAddTimer(struct FsmTimer * ft,int millisec,int event,void * arg,int where)136 mISDN_FsmAddTimer(struct FsmTimer *ft,
137 		  int millisec, int event, void *arg, int where)
138 {
139 
140 #if FSM_TIMER_DEBUG
141 	if (ft->fi->debug)
142 		ft->fi->printdebug(ft->fi, "mISDN_FsmAddTimer %lx %d %d",
143 				   (long) ft, millisec, where);
144 #endif
145 
146 	if (timer_pending(&ft->tl)) {
147 		if (ft->fi->debug) {
148 			printk(KERN_WARNING
149 			       "mISDN_FsmAddTimer: timer already active!\n");
150 			ft->fi->printdebug(ft->fi,
151 					   "mISDN_FsmAddTimer already active!");
152 		}
153 		return -1;
154 	}
155 	init_timer(&ft->tl);
156 	ft->event = event;
157 	ft->arg = arg;
158 	ft->tl.expires = jiffies + (millisec * HZ) / 1000;
159 	add_timer(&ft->tl);
160 	return 0;
161 }
162 EXPORT_SYMBOL(mISDN_FsmAddTimer);
163 
164 void
mISDN_FsmRestartTimer(struct FsmTimer * ft,int millisec,int event,void * arg,int where)165 mISDN_FsmRestartTimer(struct FsmTimer *ft,
166 		      int millisec, int event, void *arg, int where)
167 {
168 
169 #if FSM_TIMER_DEBUG
170 	if (ft->fi->debug)
171 		ft->fi->printdebug(ft->fi, "mISDN_FsmRestartTimer %lx %d %d",
172 				   (long) ft, millisec, where);
173 #endif
174 
175 	if (timer_pending(&ft->tl))
176 		del_timer(&ft->tl);
177 	init_timer(&ft->tl);
178 	ft->event = event;
179 	ft->arg = arg;
180 	ft->tl.expires = jiffies + (millisec * HZ) / 1000;
181 	add_timer(&ft->tl);
182 }
183 EXPORT_SYMBOL(mISDN_FsmRestartTimer);
184