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6#include "fsm.h"
7#include <linux/module.h>
8#include <linux/slab.h>
9#include <linux/timer.h>
10
11MODULE_AUTHOR("(C) 2000 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
12MODULE_DESCRIPTION("Finite state machine helper functions");
13MODULE_LICENSE("GPL");
14
15fsm_instance *
16init_fsm(char *name, const char **state_names, const char **event_names, int nr_states,
17 int nr_events, const fsm_node *tmpl, int tmpl_len, gfp_t order)
18{
19 int i;
20 fsm_instance *this;
21 fsm_function_t *m;
22 fsm *f;
23
24 this = kzalloc(sizeof(fsm_instance), order);
25 if (this == NULL) {
26 printk(KERN_WARNING
27 "fsm(%s): init_fsm: Couldn't alloc instance\n", name);
28 return NULL;
29 }
30 strlcpy(this->name, name, sizeof(this->name));
31 init_waitqueue_head(&this->wait_q);
32
33 f = kzalloc(sizeof(fsm), order);
34 if (f == NULL) {
35 printk(KERN_WARNING
36 "fsm(%s): init_fsm: Couldn't alloc fsm\n", name);
37 kfree_fsm(this);
38 return NULL;
39 }
40 f->nr_events = nr_events;
41 f->nr_states = nr_states;
42 f->event_names = event_names;
43 f->state_names = state_names;
44 this->f = f;
45
46 m = kcalloc(nr_states*nr_events, sizeof(fsm_function_t), order);
47 if (m == NULL) {
48 printk(KERN_WARNING
49 "fsm(%s): init_fsm: Couldn't alloc jumptable\n", name);
50 kfree_fsm(this);
51 return NULL;
52 }
53 f->jumpmatrix = m;
54
55 for (i = 0; i < tmpl_len; i++) {
56 if ((tmpl[i].cond_state >= nr_states) ||
57 (tmpl[i].cond_event >= nr_events) ) {
58 printk(KERN_ERR
59 "fsm(%s): init_fsm: Bad template l=%d st(%ld/%ld) ev(%ld/%ld)\n",
60 name, i, (long)tmpl[i].cond_state, (long)f->nr_states,
61 (long)tmpl[i].cond_event, (long)f->nr_events);
62 kfree_fsm(this);
63 return NULL;
64 } else
65 m[nr_states * tmpl[i].cond_event + tmpl[i].cond_state] =
66 tmpl[i].function;
67 }
68 return this;
69}
70
71void
72kfree_fsm(fsm_instance *this)
73{
74 if (this) {
75 if (this->f) {
76 kfree(this->f->jumpmatrix);
77 kfree(this->f);
78 }
79 kfree(this);
80 } else
81 printk(KERN_WARNING
82 "fsm: kfree_fsm called with NULL argument\n");
83}
84
85#if FSM_DEBUG_HISTORY
86void
87fsm_print_history(fsm_instance *fi)
88{
89 int idx = 0;
90 int i;
91
92 if (fi->history_size >= FSM_HISTORY_SIZE)
93 idx = fi->history_index;
94
95 printk(KERN_DEBUG "fsm(%s): History:\n", fi->name);
96 for (i = 0; i < fi->history_size; i++) {
97 int e = fi->history[idx].event;
98 int s = fi->history[idx++].state;
99 idx %= FSM_HISTORY_SIZE;
100 if (e == -1)
101 printk(KERN_DEBUG " S=%s\n",
102 fi->f->state_names[s]);
103 else
104 printk(KERN_DEBUG " S=%s E=%s\n",
105 fi->f->state_names[s],
106 fi->f->event_names[e]);
107 }
108 fi->history_size = fi->history_index = 0;
109}
110
111void
112fsm_record_history(fsm_instance *fi, int state, int event)
113{
114 fi->history[fi->history_index].state = state;
115 fi->history[fi->history_index++].event = event;
116 fi->history_index %= FSM_HISTORY_SIZE;
117 if (fi->history_size < FSM_HISTORY_SIZE)
118 fi->history_size++;
119}
120#endif
121
122const char *
123fsm_getstate_str(fsm_instance *fi)
124{
125 int st = atomic_read(&fi->state);
126 if (st >= fi->f->nr_states)
127 return "Invalid";
128 return fi->f->state_names[st];
129}
130
131static void
132fsm_expire_timer(fsm_timer *this)
133{
134#if FSM_TIMER_DEBUG
135 printk(KERN_DEBUG "fsm(%s): Timer %p expired\n",
136 this->fi->name, this);
137#endif
138 fsm_event(this->fi, this->expire_event, this->event_arg);
139}
140
141void
142fsm_settimer(fsm_instance *fi, fsm_timer *this)
143{
144 this->fi = fi;
145 this->tl.function = (void *)fsm_expire_timer;
146 this->tl.data = (long)this;
147#if FSM_TIMER_DEBUG
148 printk(KERN_DEBUG "fsm(%s): Create timer %p\n", fi->name,
149 this);
150#endif
151 init_timer(&this->tl);
152}
153
154void
155fsm_deltimer(fsm_timer *this)
156{
157#if FSM_TIMER_DEBUG
158 printk(KERN_DEBUG "fsm(%s): Delete timer %p\n", this->fi->name,
159 this);
160#endif
161 del_timer(&this->tl);
162}
163
164int
165fsm_addtimer(fsm_timer *this, int millisec, int event, void *arg)
166{
167
168#if FSM_TIMER_DEBUG
169 printk(KERN_DEBUG "fsm(%s): Add timer %p %dms\n",
170 this->fi->name, this, millisec);
171#endif
172
173 init_timer(&this->tl);
174 this->tl.function = (void *)fsm_expire_timer;
175 this->tl.data = (long)this;
176 this->expire_event = event;
177 this->event_arg = arg;
178 this->tl.expires = jiffies + (millisec * HZ) / 1000;
179 add_timer(&this->tl);
180 return 0;
181}
182
183
184void
185fsm_modtimer(fsm_timer *this, int millisec, int event, void *arg)
186{
187
188#if FSM_TIMER_DEBUG
189 printk(KERN_DEBUG "fsm(%s): Restart timer %p %dms\n",
190 this->fi->name, this, millisec);
191#endif
192
193 del_timer(&this->tl);
194 init_timer(&this->tl);
195 this->tl.function = (void *)fsm_expire_timer;
196 this->tl.data = (long)this;
197 this->expire_event = event;
198 this->event_arg = arg;
199 this->tl.expires = jiffies + (millisec * HZ) / 1000;
200 add_timer(&this->tl);
201}
202
203EXPORT_SYMBOL(init_fsm);
204EXPORT_SYMBOL(kfree_fsm);
205EXPORT_SYMBOL(fsm_settimer);
206EXPORT_SYMBOL(fsm_deltimer);
207EXPORT_SYMBOL(fsm_addtimer);
208EXPORT_SYMBOL(fsm_modtimer);
209EXPORT_SYMBOL(fsm_getstate_str);
210
211#if FSM_DEBUG_HISTORY
212EXPORT_SYMBOL(fsm_print_history);
213EXPORT_SYMBOL(fsm_record_history);
214#endif
215
