xref: /openbmc/linux/drivers/isdn/mISDN/fsm.c (revision 8dde5715)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * finite state machine implementation
4  *
5  * Author       Karsten Keil <kkeil@novell.com>
6  *
7  * Thanks to    Jan den Ouden
8  *              Fritz Elfert
9  * Copyright 2008  by Karsten Keil <kkeil@novell.com>
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/string.h>
16 #include "fsm.h"
17 
18 #define FSM_TIMER_DEBUG 0
19 
20 int
21 mISDN_FsmNew(struct Fsm *fsm,
22 	     struct FsmNode *fnlist, int fncount)
23 {
24 	int i;
25 
26 	fsm->jumpmatrix =
27 		kzalloc(array3_size(sizeof(FSMFNPTR), fsm->state_count,
28 				    fsm->event_count),
29 			GFP_KERNEL);
30 	if (fsm->jumpmatrix == NULL)
31 		return -ENOMEM;
32 
33 	for (i = 0; i < fncount; i++)
34 		if ((fnlist[i].state >= fsm->state_count) ||
35 		    (fnlist[i].event >= fsm->event_count)) {
36 			printk(KERN_ERR
37 			       "mISDN_FsmNew Error: %d st(%ld/%ld) ev(%ld/%ld)\n",
38 			       i, (long)fnlist[i].state, (long)fsm->state_count,
39 			       (long)fnlist[i].event, (long)fsm->event_count);
40 		} else
41 			fsm->jumpmatrix[fsm->state_count * fnlist[i].event +
42 					fnlist[i].state] = (FSMFNPTR) fnlist[i].routine;
43 	return 0;
44 }
45 EXPORT_SYMBOL(mISDN_FsmNew);
46 
47 void
48 mISDN_FsmFree(struct Fsm *fsm)
49 {
50 	kfree((void *) fsm->jumpmatrix);
51 }
52 EXPORT_SYMBOL(mISDN_FsmFree);
53 
54 int
55 mISDN_FsmEvent(struct FsmInst *fi, int event, void *arg)
56 {
57 	FSMFNPTR r;
58 
59 	if ((fi->state >= fi->fsm->state_count) ||
60 	    (event >= fi->fsm->event_count)) {
61 		printk(KERN_ERR
62 		       "mISDN_FsmEvent Error st(%ld/%ld) ev(%d/%ld)\n",
63 		       (long)fi->state, (long)fi->fsm->state_count, event,
64 		       (long)fi->fsm->event_count);
65 		return 1;
66 	}
67 	r = fi->fsm->jumpmatrix[fi->fsm->state_count * event + fi->state];
68 	if (r) {
69 		if (fi->debug)
70 			fi->printdebug(fi, "State %s Event %s",
71 				       fi->fsm->strState[fi->state],
72 				       fi->fsm->strEvent[event]);
73 		r(fi, event, arg);
74 		return 0;
75 	} else {
76 		if (fi->debug)
77 			fi->printdebug(fi, "State %s Event %s no action",
78 				       fi->fsm->strState[fi->state],
79 				       fi->fsm->strEvent[event]);
80 		return 1;
81 	}
82 }
83 EXPORT_SYMBOL(mISDN_FsmEvent);
84 
85 void
86 mISDN_FsmChangeState(struct FsmInst *fi, int newstate)
87 {
88 	fi->state = newstate;
89 	if (fi->debug)
90 		fi->printdebug(fi, "ChangeState %s",
91 			       fi->fsm->strState[newstate]);
92 }
93 EXPORT_SYMBOL(mISDN_FsmChangeState);
94 
95 static void
96 FsmExpireTimer(struct timer_list *t)
97 {
98 	struct FsmTimer *ft = from_timer(ft, t, tl);
99 #if FSM_TIMER_DEBUG
100 	if (ft->fi->debug)
101 		ft->fi->printdebug(ft->fi, "FsmExpireTimer %lx", (long) ft);
102 #endif
103 	mISDN_FsmEvent(ft->fi, ft->event, ft->arg);
104 }
105 
106 void
107 mISDN_FsmInitTimer(struct FsmInst *fi, struct FsmTimer *ft)
108 {
109 	ft->fi = fi;
110 #if FSM_TIMER_DEBUG
111 	if (ft->fi->debug)
112 		ft->fi->printdebug(ft->fi, "mISDN_FsmInitTimer %lx", (long) ft);
113 #endif
114 	timer_setup(&ft->tl, FsmExpireTimer, 0);
115 }
116 EXPORT_SYMBOL(mISDN_FsmInitTimer);
117 
118 void
119 mISDN_FsmDelTimer(struct FsmTimer *ft, int where)
120 {
121 #if FSM_TIMER_DEBUG
122 	if (ft->fi->debug)
123 		ft->fi->printdebug(ft->fi, "mISDN_FsmDelTimer %lx %d",
124 				   (long) ft, where);
125 #endif
126 	del_timer(&ft->tl);
127 }
128 EXPORT_SYMBOL(mISDN_FsmDelTimer);
129 
130 int
131 mISDN_FsmAddTimer(struct FsmTimer *ft,
132 		  int millisec, int event, void *arg, int where)
133 {
134 
135 #if FSM_TIMER_DEBUG
136 	if (ft->fi->debug)
137 		ft->fi->printdebug(ft->fi, "mISDN_FsmAddTimer %lx %d %d",
138 				   (long) ft, millisec, where);
139 #endif
140 
141 	if (timer_pending(&ft->tl)) {
142 		if (ft->fi->debug) {
143 			printk(KERN_WARNING
144 			       "mISDN_FsmAddTimer: timer already active!\n");
145 			ft->fi->printdebug(ft->fi,
146 					   "mISDN_FsmAddTimer already active!");
147 		}
148 		return -1;
149 	}
150 	ft->event = event;
151 	ft->arg = arg;
152 	ft->tl.expires = jiffies + (millisec * HZ) / 1000;
153 	add_timer(&ft->tl);
154 	return 0;
155 }
156 EXPORT_SYMBOL(mISDN_FsmAddTimer);
157 
158 void
159 mISDN_FsmRestartTimer(struct FsmTimer *ft,
160 		      int millisec, int event, void *arg, int where)
161 {
162 
163 #if FSM_TIMER_DEBUG
164 	if (ft->fi->debug)
165 		ft->fi->printdebug(ft->fi, "mISDN_FsmRestartTimer %lx %d %d",
166 				   (long) ft, millisec, where);
167 #endif
168 
169 	if (timer_pending(&ft->tl))
170 		del_timer(&ft->tl);
171 	ft->event = event;
172 	ft->arg = arg;
173 	ft->tl.expires = jiffies + (millisec * HZ) / 1000;
174 	add_timer(&ft->tl);
175 }
176 EXPORT_SYMBOL(mISDN_FsmRestartTimer);
177