xref: /linux/drivers/isdn/mISDN/fsm.c (revision bd628c1bed7902ec1f24ba0fe70758949146abbe)
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 int
30 mISDN_FsmNew(struct Fsm *fsm,
31 	     struct FsmNode *fnlist, int fncount)
32 {
33 	int i;
34 
35 	fsm->jumpmatrix =
36 		kzalloc(array3_size(sizeof(FSMFNPTR), fsm->state_count,
37 				    fsm->event_count),
38 			GFP_KERNEL);
39 	if (fsm->jumpmatrix == NULL)
40 		return -ENOMEM;
41 
42 	for (i = 0; i < fncount; i++)
43 		if ((fnlist[i].state >= fsm->state_count) ||
44 		    (fnlist[i].event >= fsm->event_count)) {
45 			printk(KERN_ERR
46 			       "mISDN_FsmNew Error: %d st(%ld/%ld) ev(%ld/%ld)\n",
47 			       i, (long)fnlist[i].state, (long)fsm->state_count,
48 			       (long)fnlist[i].event, (long)fsm->event_count);
49 		} else
50 			fsm->jumpmatrix[fsm->state_count * fnlist[i].event +
51 					fnlist[i].state] = (FSMFNPTR) fnlist[i].routine;
52 	return 0;
53 }
54 EXPORT_SYMBOL(mISDN_FsmNew);
55 
56 void
57 mISDN_FsmFree(struct Fsm *fsm)
58 {
59 	kfree((void *) fsm->jumpmatrix);
60 }
61 EXPORT_SYMBOL(mISDN_FsmFree);
62 
63 int
64 mISDN_FsmEvent(struct FsmInst *fi, int event, void *arg)
65 {
66 	FSMFNPTR r;
67 
68 	if ((fi->state >= fi->fsm->state_count) ||
69 	    (event >= fi->fsm->event_count)) {
70 		printk(KERN_ERR
71 		       "mISDN_FsmEvent Error st(%ld/%ld) ev(%d/%ld)\n",
72 		       (long)fi->state, (long)fi->fsm->state_count, event,
73 		       (long)fi->fsm->event_count);
74 		return 1;
75 	}
76 	r = fi->fsm->jumpmatrix[fi->fsm->state_count * event + fi->state];
77 	if (r) {
78 		if (fi->debug)
79 			fi->printdebug(fi, "State %s Event %s",
80 				       fi->fsm->strState[fi->state],
81 				       fi->fsm->strEvent[event]);
82 		r(fi, event, arg);
83 		return 0;
84 	} else {
85 		if (fi->debug)
86 			fi->printdebug(fi, "State %s Event %s no action",
87 				       fi->fsm->strState[fi->state],
88 				       fi->fsm->strEvent[event]);
89 		return 1;
90 	}
91 }
92 EXPORT_SYMBOL(mISDN_FsmEvent);
93 
94 void
95 mISDN_FsmChangeState(struct FsmInst *fi, int newstate)
96 {
97 	fi->state = newstate;
98 	if (fi->debug)
99 		fi->printdebug(fi, "ChangeState %s",
100 			       fi->fsm->strState[newstate]);
101 }
102 EXPORT_SYMBOL(mISDN_FsmChangeState);
103 
104 static void
105 FsmExpireTimer(struct timer_list *t)
106 {
107 	struct FsmTimer *ft = from_timer(ft, t, tl);
108 #if FSM_TIMER_DEBUG
109 	if (ft->fi->debug)
110 		ft->fi->printdebug(ft->fi, "FsmExpireTimer %lx", (long) ft);
111 #endif
112 	mISDN_FsmEvent(ft->fi, ft->event, ft->arg);
113 }
114 
115 void
116 mISDN_FsmInitTimer(struct FsmInst *fi, struct FsmTimer *ft)
117 {
118 	ft->fi = fi;
119 #if FSM_TIMER_DEBUG
120 	if (ft->fi->debug)
121 		ft->fi->printdebug(ft->fi, "mISDN_FsmInitTimer %lx", (long) ft);
122 #endif
123 	timer_setup(&ft->tl, FsmExpireTimer, 0);
124 }
125 EXPORT_SYMBOL(mISDN_FsmInitTimer);
126 
127 void
128 mISDN_FsmDelTimer(struct FsmTimer *ft, int where)
129 {
130 #if FSM_TIMER_DEBUG
131 	if (ft->fi->debug)
132 		ft->fi->printdebug(ft->fi, "mISDN_FsmDelTimer %lx %d",
133 				   (long) ft, where);
134 #endif
135 	del_timer(&ft->tl);
136 }
137 EXPORT_SYMBOL(mISDN_FsmDelTimer);
138 
139 int
140 mISDN_FsmAddTimer(struct FsmTimer *ft,
141 		  int millisec, int event, void *arg, int where)
142 {
143 
144 #if FSM_TIMER_DEBUG
145 	if (ft->fi->debug)
146 		ft->fi->printdebug(ft->fi, "mISDN_FsmAddTimer %lx %d %d",
147 				   (long) ft, millisec, where);
148 #endif
149 
150 	if (timer_pending(&ft->tl)) {
151 		if (ft->fi->debug) {
152 			printk(KERN_WARNING
153 			       "mISDN_FsmAddTimer: timer already active!\n");
154 			ft->fi->printdebug(ft->fi,
155 					   "mISDN_FsmAddTimer already active!");
156 		}
157 		return -1;
158 	}
159 	ft->event = event;
160 	ft->arg = arg;
161 	ft->tl.expires = jiffies + (millisec * HZ) / 1000;
162 	add_timer(&ft->tl);
163 	return 0;
164 }
165 EXPORT_SYMBOL(mISDN_FsmAddTimer);
166 
167 void
168 mISDN_FsmRestartTimer(struct FsmTimer *ft,
169 		      int millisec, int event, void *arg, int where)
170 {
171 
172 #if FSM_TIMER_DEBUG
173 	if (ft->fi->debug)
174 		ft->fi->printdebug(ft->fi, "mISDN_FsmRestartTimer %lx %d %d",
175 				   (long) ft, millisec, where);
176 #endif
177 
178 	if (timer_pending(&ft->tl))
179 		del_timer(&ft->tl);
180 	ft->event = event;
181 	ft->arg = arg;
182 	ft->tl.expires = jiffies + (millisec * HZ) / 1000;
183 	add_timer(&ft->tl);
184 }
185 EXPORT_SYMBOL(mISDN_FsmRestartTimer);
186