fsm.c

  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
 20int
 21mISDN_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}
 45EXPORT_SYMBOL(mISDN_FsmNew);
 46
 47void
 48mISDN_FsmFree(struct Fsm *fsm)
 49{
 50	kfree((void *) fsm->jumpmatrix);
 51}
 52EXPORT_SYMBOL(mISDN_FsmFree);
 53
 54int
 55mISDN_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}
 83EXPORT_SYMBOL(mISDN_FsmEvent);
 84
 85void
 86mISDN_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}
 93EXPORT_SYMBOL(mISDN_FsmChangeState);
 94
 95static void
 96FsmExpireTimer(struct timer_list *t)
 97{
 98	struct FsmTimer *ft = timer_container_of(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
106void
107mISDN_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}
116EXPORT_SYMBOL(mISDN_FsmInitTimer);
117
118void
119mISDN_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	timer_delete(&ft->tl);
127}
128EXPORT_SYMBOL(mISDN_FsmDelTimer);
129
130int
131mISDN_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}
156EXPORT_SYMBOL(mISDN_FsmAddTimer);
157
158void
159mISDN_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		timer_delete(&ft->tl);
171	ft->event = event;
172	ft->arg = arg;
173	ft->tl.expires = jiffies + (millisec * HZ) / 1000;
174	add_timer(&ft->tl);
175}
176EXPORT_SYMBOL(mISDN_FsmRestartTimer);