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5
6#include "fsm.h"
7#include <linux/module.h>
8#include <linux/timer.h>
9
10MODULE_AUTHOR("(C) 2000 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
11MODULE_DESCRIPTION("Finite state machine helper functions");
12MODULE_LICENSE("GPL");
13
14fsm_instance *
15init_fsm(char *name, const char **state_names, const char **event_names, int nr_states,
16 int nr_events, const fsm_node *tmpl, int tmpl_len, gfp_t order)
17{
18 int i;
19 fsm_instance *this;
20 fsm_function_t *m;
21 fsm *f;
22
23 this = kzalloc(sizeof(fsm_instance), order);
24 if (this == NULL) {
25 printk(KERN_WARNING
26 "fsm(%s): init_fsm: Couldn't alloc instance\n", name);
27 return NULL;
28 }
29 strlcpy(this->name, name, sizeof(this->name));
30
31 f = kzalloc(sizeof(fsm), order);
32 if (f == NULL) {
33 printk(KERN_WARNING
34 "fsm(%s): init_fsm: Couldn't alloc fsm\n", name);
35 kfree_fsm(this);
36 return NULL;
37 }
38 f->nr_events = nr_events;
39 f->nr_states = nr_states;
40 f->event_names = event_names;
41 f->state_names = state_names;
42 this->f = f;
43
44 m = kcalloc(nr_states*nr_events, sizeof(fsm_function_t), order);
45 if (m == NULL) {
46 printk(KERN_WARNING
47 "fsm(%s): init_fsm: Couldn't alloc jumptable\n", name);
48 kfree_fsm(this);
49 return NULL;
50 }
51 f->jumpmatrix = m;
52
53 for (i = 0; i < tmpl_len; i++) {
54 if ((tmpl[i].cond_state >= nr_states) ||
55 (tmpl[i].cond_event >= nr_events) ) {
56 printk(KERN_ERR
57 "fsm(%s): init_fsm: Bad template l=%d st(%ld/%ld) ev(%ld/%ld)\n",
58 name, i, (long)tmpl[i].cond_state, (long)f->nr_states,
59 (long)tmpl[i].cond_event, (long)f->nr_events);
60 kfree_fsm(this);
61 return NULL;
62 } else
63 m[nr_states * tmpl[i].cond_event + tmpl[i].cond_state] =
64 tmpl[i].function;
65 }
66 return this;
67}
68
69void
70kfree_fsm(fsm_instance *this)
71{
72 if (this) {
73 if (this->f) {
74 kfree(this->f->jumpmatrix);
75 kfree(this->f);
76 }
77 kfree(this);
78 } else
79 printk(KERN_WARNING
80 "fsm: kfree_fsm called with NULL argument\n");
81}
82
83#if FSM_DEBUG_HISTORY
84void
85fsm_print_history(fsm_instance *fi)
86{
87 int idx = 0;
88 int i;
89
90 if (fi->history_size >= FSM_HISTORY_SIZE)
91 idx = fi->history_index;
92
93 printk(KERN_DEBUG "fsm(%s): History:\n", fi->name);
94 for (i = 0; i < fi->history_size; i++) {
95 int e = fi->history[idx].event;
96 int s = fi->history[idx++].state;
97 idx %= FSM_HISTORY_SIZE;
98 if (e == -1)
99 printk(KERN_DEBUG " S=%s\n",
100 fi->f->state_names[s]);
101 else
102 printk(KERN_DEBUG " S=%s E=%s\n",
103 fi->f->state_names[s],
104 fi->f->event_names[e]);
105 }
106 fi->history_size = fi->history_index = 0;
107}
108
109void
110fsm_record_history(fsm_instance *fi, int state, int event)
111{
112 fi->history[fi->history_index].state = state;
113 fi->history[fi->history_index++].event = event;
114 fi->history_index %= FSM_HISTORY_SIZE;
115 if (fi->history_size < FSM_HISTORY_SIZE)
116 fi->history_size++;
117}
118#endif
119
120const char *
121fsm_getstate_str(fsm_instance *fi)
122{
123 int st = atomic_read(&fi->state);
124 if (st >= fi->f->nr_states)
125 return "Invalid";
126 return fi->f->state_names[st];
127}
128
129static void
130fsm_expire_timer(fsm_timer *this)
131{
132#if FSM_TIMER_DEBUG
133 printk(KERN_DEBUG "fsm(%s): Timer %p expired\n",
134 this->fi->name, this);
135#endif
136 fsm_event(this->fi, this->expire_event, this->event_arg);
137}
138
139void
140fsm_settimer(fsm_instance *fi, fsm_timer *this)
141{
142 this->fi = fi;
143 this->tl.function = (void *)fsm_expire_timer;
144 this->tl.data = (long)this;
145#if FSM_TIMER_DEBUG
146 printk(KERN_DEBUG "fsm(%s): Create timer %p\n", fi->name,
147 this);
148#endif
149 init_timer(&this->tl);
150}
151
152void
153fsm_deltimer(fsm_timer *this)
154{
155#if FSM_TIMER_DEBUG
156 printk(KERN_DEBUG "fsm(%s): Delete timer %p\n", this->fi->name,
157 this);
158#endif
159 del_timer(&this->tl);
160}
161
162int
163fsm_addtimer(fsm_timer *this, int millisec, int event, void *arg)
164{
165
166#if FSM_TIMER_DEBUG
167 printk(KERN_DEBUG "fsm(%s): Add timer %p %dms\n",
168 this->fi->name, this, millisec);
169#endif
170
171 init_timer(&this->tl);
172 this->tl.function = (void *)fsm_expire_timer;
173 this->tl.data = (long)this;
174 this->expire_event = event;
175 this->event_arg = arg;
176 this->tl.expires = jiffies + (millisec * HZ) / 1000;
177 add_timer(&this->tl);
178 return 0;
179}
180
181
182void
183fsm_modtimer(fsm_timer *this, int millisec, int event, void *arg)
184{
185
186#if FSM_TIMER_DEBUG
187 printk(KERN_DEBUG "fsm(%s): Restart timer %p %dms\n",
188 this->fi->name, this, millisec);
189#endif
190
191 del_timer(&this->tl);
192 init_timer(&this->tl);
193 this->tl.function = (void *)fsm_expire_timer;
194 this->tl.data = (long)this;
195 this->expire_event = event;
196 this->event_arg = arg;
197 this->tl.expires = jiffies + (millisec * HZ) / 1000;
198 add_timer(&this->tl);
199}
200
201EXPORT_SYMBOL(init_fsm);
202EXPORT_SYMBOL(kfree_fsm);
203EXPORT_SYMBOL(fsm_settimer);
204EXPORT_SYMBOL(fsm_deltimer);
205EXPORT_SYMBOL(fsm_addtimer);
206EXPORT_SYMBOL(fsm_modtimer);
207EXPORT_SYMBOL(fsm_getstate_str);
208
209#if FSM_DEBUG_HISTORY
210EXPORT_SYMBOL(fsm_print_history);
211EXPORT_SYMBOL(fsm_record_history);
212#endif
213
