1/*
2 * DSS.1 Finite State Machine
3 * base: ITU-T Rec Q.931
4 *
5 * Copyright (C) 1996 Universidade de Lisboa
6 *
7 * Written by Pedro Roque Marques (roque@di.fc.ul.pt)
8 *
9 * This software may be used and distributed according to the terms of
10 * the GNU General Public License, incorporated herein by reference.
11 */
12
13/*
14 *        TODO: complete the FSM
15 *              move state/event descriptions to a user space logger
16 */
17
18#include <linux/string.h>
19#include <linux/kernel.h>
20
21#include <linux/types.h>
22#include <linux/mm.h>
23#include <linux/skbuff.h>
24
25#include <linux/timer.h>
26#include <asm/io.h>
27
28#include <linux/isdnif.h>
29
30#include "pcbit.h"
31#include "edss1.h"
32#include "layer2.h"
33#include "callbacks.h"
34
35
36const char * const isdn_state_table[] = {
37	"Closed",
38	"Call initiated",
39	"Overlap sending",
40	"Outgoing call proceeding",
41	"NOT DEFINED",
42	"Call delivered",
43	"Call present",
44	"Call received",
45	"Connect request",
46	"Incoming call proceeding",
47	"Active",
48	"Disconnect request",
49	"Disconnect indication",
50	"NOT DEFINED",
51	"NOT DEFINED",
52	"Suspend request",
53	"NOT DEFINED",
54	"Resume request",
55	"NOT DEFINED",
56	"Release Request",
57	"NOT DEFINED",
58	"NOT DEFINED",
59	"NOT DEFINED",
60	"NOT DEFINED",
61	"NOT DEFINED",
62	"Overlap receiving",
63	"Select protocol on B-Channel",
64	"Activate B-channel protocol"
65};
66
67#ifdef DEBUG_ERRS
68static
69struct CauseValue {
70	byte nr;
71	char *descr;
72} cvlist[] = {
73	{0x01, "Unallocated (unassigned) number"},
74	{0x02, "No route to specified transit network"},
75	{0x03, "No route to destination"},
76	{0x04, "Send special information tone"},
77	{0x05, "Misdialled trunk prefix"},
78	{0x06, "Channel unacceptable"},
79	{0x07, "Channel awarded and being delivered in an established channel"},
80	{0x08, "Preemption"},
81	{0x09, "Preemption - circuit reserved for reuse"},
82	{0x10, "Normal call clearing"},
83	{0x11, "User busy"},
84	{0x12, "No user responding"},
85	{0x13, "No answer from user (user alerted)"},
86	{0x14, "Subscriber absent"},
87	{0x15, "Call rejected"},
88	{0x16, "Number changed"},
89	{0x1a, "non-selected user clearing"},
90	{0x1b, "Destination out of order"},
91	{0x1c, "Invalid number format (address incomplete)"},
92	{0x1d, "Facility rejected"},
93	{0x1e, "Response to Status enquiry"},
94	{0x1f, "Normal, unspecified"},
95	{0x22, "No circuit/channel available"},
96	{0x26, "Network out of order"},
97	{0x27, "Permanent frame mode connection out-of-service"},
98	{0x28, "Permanent frame mode connection operational"},
99	{0x29, "Temporary failure"},
100	{0x2a, "Switching equipment congestion"},
101	{0x2b, "Access information discarded"},
102	{0x2c, "Requested circuit/channel not available"},
103	{0x2e, "Precedence call blocked"},
104	{0x2f, "Resource unavailable, unspecified"},
105	{0x31, "Quality of service unavailable"},
106	{0x32, "Requested facility not subscribed"},
107	{0x35, "Outgoing calls barred within CUG"},
108	{0x37, "Incoming calls barred within CUG"},
109	{0x39, "Bearer capability not authorized"},
110	{0x3a, "Bearer capability not presently available"},
111	{0x3e, "Inconsistency in designated outgoing access information and subscriber class"},
112	{0x3f, "Service or option not available, unspecified"},
113	{0x41, "Bearer capability not implemented"},
114	{0x42, "Channel type not implemented"},
115	{0x43, "Requested facility not implemented"},
116	{0x44, "Only restricted digital information bearer capability is available"},
117	{0x4f, "Service or option not implemented"},
118	{0x51, "Invalid call reference value"},
119	{0x52, "Identified channel does not exist"},
120	{0x53, "A suspended call exists, but this call identity does not"},
121	{0x54, "Call identity in use"},
122	{0x55, "No call suspended"},
123	{0x56, "Call having the requested call identity has been cleared"},
124	{0x57, "User not member of CUG"},
125	{0x58, "Incompatible destination"},
126	{0x5a, "Non-existent CUG"},
127	{0x5b, "Invalid transit network selection"},
128	{0x5f, "Invalid message, unspecified"},
129	{0x60, "Mandatory information element is missing"},
130	{0x61, "Message type non-existent or not implemented"},
131	{0x62, "Message not compatible with call state or message type non-existent or not implemented"},
132	{0x63, "Information element/parameter non-existent or not implemented"},
133	{0x64, "Invalid information element contents"},
134	{0x65, "Message not compatible with call state"},
135	{0x66, "Recovery on timer expiry"},
136	{0x67, "Parameter non-existent or not implemented - passed on"},
137	{0x6e, "Message with unrecognized parameter discarded"},
138	{0x6f, "Protocol error, unspecified"},
139	{0x7f, "Interworking, unspecified"}
140};
141
142#endif
143
144static struct isdn_event_desc {
145	unsigned short ev;
146	char *desc;
147} isdn_event_table[] = {
148	{EV_USR_SETUP_REQ,     "CC->L3: Setup Request"},
149	{EV_USR_SETUP_RESP,    "CC->L3: Setup Response"},
150	{EV_USR_PROCED_REQ,    "CC->L3: Proceeding Request"},
151	{EV_USR_RELEASE_REQ,   "CC->L3: Release Request"},
152
153	{EV_NET_SETUP,        "NET->TE: setup "},
154	{EV_NET_CALL_PROC,    "NET->TE: call proceeding"},
155	{EV_NET_SETUP_ACK,    "NET->TE: setup acknowledge (more info needed)"},
156	{EV_NET_CONN,         "NET->TE: connect"},
157	{EV_NET_CONN_ACK,     "NET->TE: connect acknowledge"},
158	{EV_NET_DISC,         "NET->TE: disconnect indication"},
159	{EV_NET_RELEASE,      "NET->TE: release"},
160	{EV_NET_RELEASE_COMP, "NET->TE: release complete"},
161	{EV_NET_SELP_RESP,    "Board: Select B-channel protocol ack"},
162	{EV_NET_ACTV_RESP,    "Board: Activate B-channel protocol ack"},
163	{EV_TIMER,            "Timeout"},
164	{0, "NULL"}
165};
166
167char *strisdnevent(ushort ev)
168{
169	struct isdn_event_desc *entry;
170
171	for (entry = isdn_event_table; entry->ev; entry++)
172		if (entry->ev == ev)
173			break;
174
175	return entry->desc;
176}
177
178/*
179 * Euro ISDN finite state machine
180 */
181
182static struct fsm_timer_entry fsm_timers[] = {
183	{ST_CALL_PROC, 10},
184	{ST_DISC_REQ, 2},
185	{ST_ACTIVE_SELP, 5},
186	{ST_ACTIVE_ACTV, 5},
187	{ST_INCM_PROC, 10},
188	{ST_CONN_REQ, 2},
189	{0xff, 0}
190};
191
192static struct fsm_entry fsm_table[] = {
193/* Connect Phase */
194	/* Outgoing */
195	{ST_NULL, ST_CALL_INIT, EV_USR_SETUP_REQ, cb_out_1},
196
197	{ST_CALL_INIT, ST_OVER_SEND, EV_NET_SETUP_ACK, cb_notdone},
198	{ST_CALL_INIT, ST_CALL_PROC, EV_NET_CALL_PROC, NULL},
199	{ST_CALL_INIT, ST_NULL, EV_NET_DISC, cb_out_2},
200
201	{ST_CALL_PROC, ST_ACTIVE_SELP, EV_NET_CONN, cb_out_2},
202	{ST_CALL_PROC, ST_NULL, EV_NET_DISC, cb_disc_1},
203	{ST_CALL_PROC, ST_DISC_REQ, EV_USR_RELEASE_REQ, cb_disc_2},
204
205	/* Incoming */
206	{ST_NULL, ST_CALL_PRES, EV_NET_SETUP, NULL},
207
208	{ST_CALL_PRES, ST_INCM_PROC, EV_USR_PROCED_REQ, cb_in_1},
209	{ST_CALL_PRES, ST_DISC_REQ, EV_USR_RELEASE_REQ, cb_disc_2},
210
211	{ST_INCM_PROC, ST_CONN_REQ, EV_USR_SETUP_RESP, cb_in_2},
212	{ST_INCM_PROC, ST_DISC_REQ, EV_USR_RELEASE_REQ, cb_disc_2},
213
214	{ST_CONN_REQ, ST_ACTIVE_SELP, EV_NET_CONN_ACK, cb_in_3},
215
216	/* Active */
217	{ST_ACTIVE, ST_NULL, EV_NET_DISC, cb_disc_1},
218	{ST_ACTIVE, ST_DISC_REQ, EV_USR_RELEASE_REQ, cb_disc_2},
219	{ST_ACTIVE, ST_NULL, EV_NET_RELEASE, cb_disc_3},
220
221	/* Disconnect */
222
223	{ST_DISC_REQ, ST_NULL, EV_NET_DISC, cb_disc_1},
224	{ST_DISC_REQ, ST_NULL, EV_NET_RELEASE, cb_disc_3},
225
226	/* protocol selection */
227	{ST_ACTIVE_SELP, ST_ACTIVE_ACTV, EV_NET_SELP_RESP, cb_selp_1},
228	{ST_ACTIVE_SELP, ST_DISC_REQ, EV_USR_RELEASE_REQ, cb_disc_2},
229
230	{ST_ACTIVE_ACTV, ST_ACTIVE, EV_NET_ACTV_RESP, cb_open},
231	{ST_ACTIVE_ACTV, ST_DISC_REQ, EV_USR_RELEASE_REQ, cb_disc_2},
232
233	/* Timers */
234	{ST_CALL_PROC, ST_DISC_REQ, EV_TIMER, cb_disc_2},
235	{ST_DISC_REQ, ST_NULL, EV_TIMER, cb_disc_3},
236	{ST_ACTIVE_SELP, ST_DISC_REQ, EV_TIMER, cb_disc_2},
237	{ST_ACTIVE_ACTV, ST_DISC_REQ, EV_TIMER, cb_disc_2},
238	{ST_INCM_PROC, ST_DISC_REQ, EV_TIMER, cb_disc_2},
239	{ST_CONN_REQ, ST_CONN_REQ, EV_TIMER, cb_in_2},
240
241	{0xff, 0, 0, NULL}
242};
243
244
245static void pcbit_fsm_timer(unsigned long data)
246{
247	struct pcbit_dev *dev;
248	struct pcbit_chan *chan;
249
250	chan = (struct pcbit_chan *) data;
251
252	del_timer(&chan->fsm_timer);
253	chan->fsm_timer.function = NULL;
254
255	dev = chan2dev(chan);
256
257	if (dev == NULL) {
258		printk(KERN_WARNING "pcbit: timer for unknown device\n");
259		return;
260	}
261
262	pcbit_fsm_event(dev, chan, EV_TIMER, NULL);
263}
264
265
266void pcbit_fsm_event(struct pcbit_dev *dev, struct pcbit_chan *chan,
267		     unsigned short event, struct callb_data *data)
268{
269	struct fsm_entry *action;
270	struct fsm_timer_entry *tentry;
271	unsigned long flags;
272
273	spin_lock_irqsave(&dev->lock, flags);
274
275	for (action = fsm_table; action->init != 0xff; action++)
276		if (action->init == chan->fsm_state && action->event == event)
277			break;
278
279	if (action->init == 0xff) {
280
281		spin_unlock_irqrestore(&dev->lock, flags);
282		printk(KERN_DEBUG "fsm error: event %x on state %x\n",
283		       event, chan->fsm_state);
284		return;
285	}
286
287	if (chan->fsm_timer.function) {
288		del_timer(&chan->fsm_timer);
289		chan->fsm_timer.function = NULL;
290	}
291
292	chan->fsm_state = action->final;
293
294	pcbit_state_change(dev, chan, action->init, event, action->final);
295
296	for (tentry = fsm_timers; tentry->init != 0xff; tentry++)
297		if (tentry->init == chan->fsm_state)
298			break;
299
300	if (tentry->init != 0xff) {
301		init_timer(&chan->fsm_timer);
302		chan->fsm_timer.function = &pcbit_fsm_timer;
303		chan->fsm_timer.data = (ulong) chan;
304		chan->fsm_timer.expires = jiffies + tentry->timeout * HZ;
305		add_timer(&chan->fsm_timer);
306	}
307
308	spin_unlock_irqrestore(&dev->lock, flags);
309
310	if (action->callb)
311		action->callb(dev, chan, data);
312
313}
314