1/*********************************************************************
2 *
3 * Filename:      ircomm_lmp.c
4 * Version:       1.0
5 * Description:   Interface between IrCOMM and IrLMP
6 * Status:        Stable
7 * Author:        Dag Brattli <dagb@cs.uit.no>
8 * Created at:    Sun Jun  6 20:48:27 1999
9 * Modified at:   Sun Dec 12 13:44:17 1999
10 * Modified by:   Dag Brattli <dagb@cs.uit.no>
11 * Sources:       Previous IrLPT work by Thomas Davis
12 *
13 *     Copyright (c) 1999 Dag Brattli, All Rights Reserved.
14 *     Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
15 *
16 *     This program is free software; you can redistribute it and/or
17 *     modify it under the terms of the GNU General Public License as
18 *     published by the Free Software Foundation; either version 2 of
19 *     the License, or (at your option) any later version.
20 *
21 *     This program is distributed in the hope that it will be useful,
22 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
23 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24 *     GNU General Public License for more details.
25 *
26 *     You should have received a copy of the GNU General Public License
27 *     along with this program; if not, see <http://www.gnu.org/licenses/>.
28 *
29 ********************************************************************/
30
31#include <linux/init.h>
32#include <linux/gfp.h>
33
34#include <net/irda/irda.h>
35#include <net/irda/irlmp.h>
36#include <net/irda/iriap.h>
37#include <net/irda/irda_device.h>	/* struct irda_skb_cb */
38
39#include <net/irda/ircomm_event.h>
40#include <net/irda/ircomm_lmp.h>
41
42
43/*
44 * Function ircomm_lmp_connect_request (self, userdata)
45 *
46 *
47 *
48 */
49static int ircomm_lmp_connect_request(struct ircomm_cb *self,
50				      struct sk_buff *userdata,
51				      struct ircomm_info *info)
52{
53	int ret = 0;
54
55	IRDA_DEBUG(0, "%s()\n", __func__ );
56
57	/* Don't forget to refcount it - should be NULL anyway */
58	if(userdata)
59		skb_get(userdata);
60
61	ret = irlmp_connect_request(self->lsap, info->dlsap_sel,
62				    info->saddr, info->daddr, NULL, userdata);
63	return ret;
64}
65
66/*
67 * Function ircomm_lmp_connect_response (self, skb)
68 *
69 *
70 *
71 */
72static int ircomm_lmp_connect_response(struct ircomm_cb *self,
73				       struct sk_buff *userdata)
74{
75	struct sk_buff *tx_skb;
76
77	IRDA_DEBUG(0, "%s()\n", __func__ );
78
79	/* Any userdata supplied? */
80	if (userdata == NULL) {
81		tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
82		if (!tx_skb)
83			return -ENOMEM;
84
85		/* Reserve space for MUX and LAP header */
86		skb_reserve(tx_skb, LMP_MAX_HEADER);
87	} else {
88		/*
89		 *  Check that the client has reserved enough space for
90		 *  headers
91		 */
92		IRDA_ASSERT(skb_headroom(userdata) >= LMP_MAX_HEADER,
93			    return -1;);
94
95		/* Don't forget to refcount it - should be NULL anyway */
96		skb_get(userdata);
97		tx_skb = userdata;
98	}
99
100	return irlmp_connect_response(self->lsap, tx_skb);
101}
102
103static int ircomm_lmp_disconnect_request(struct ircomm_cb *self,
104					 struct sk_buff *userdata,
105					 struct ircomm_info *info)
106{
107	struct sk_buff *tx_skb;
108	int ret;
109
110	IRDA_DEBUG(0, "%s()\n", __func__ );
111
112	if (!userdata) {
113		tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
114		if (!tx_skb)
115			return -ENOMEM;
116
117		/*  Reserve space for MUX and LAP header */
118		skb_reserve(tx_skb, LMP_MAX_HEADER);
119		userdata = tx_skb;
120	} else {
121		/* Don't forget to refcount it - should be NULL anyway */
122		skb_get(userdata);
123	}
124
125	ret = irlmp_disconnect_request(self->lsap, userdata);
126
127	return ret;
128}
129
130/*
131 * Function ircomm_lmp_flow_control (skb)
132 *
133 *    This function is called when a data frame we have sent to IrLAP has
134 *    been deallocated. We do this to make sure we don't flood IrLAP with
135 *    frames, since we are not using the IrTTP flow control mechanism
136 */
137static void ircomm_lmp_flow_control(struct sk_buff *skb)
138{
139	struct irda_skb_cb *cb;
140	struct ircomm_cb *self;
141	int line;
142
143	IRDA_ASSERT(skb != NULL, return;);
144
145	cb = (struct irda_skb_cb *) skb->cb;
146
147	IRDA_DEBUG(2, "%s()\n", __func__ );
148
149	line = cb->line;
150
151	self = (struct ircomm_cb *) hashbin_lock_find(ircomm, line, NULL);
152	if (!self) {
153		IRDA_DEBUG(2, "%s(), didn't find myself\n", __func__ );
154		return;
155	}
156
157	IRDA_ASSERT(self != NULL, return;);
158	IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
159
160	self->pkt_count--;
161
162	if ((self->pkt_count < 2) && (self->flow_status == FLOW_STOP)) {
163		IRDA_DEBUG(2, "%s(), asking TTY to start again!\n", __func__ );
164		self->flow_status = FLOW_START;
165		if (self->notify.flow_indication)
166			self->notify.flow_indication(self->notify.instance,
167						     self, FLOW_START);
168	}
169}
170
171/*
172 * Function ircomm_lmp_data_request (self, userdata)
173 *
174 *    Send data frame to peer device
175 *
176 */
177static int ircomm_lmp_data_request(struct ircomm_cb *self,
178				   struct sk_buff *skb,
179				   int not_used)
180{
181	struct irda_skb_cb *cb;
182	int ret;
183
184	IRDA_ASSERT(skb != NULL, return -1;);
185
186	cb = (struct irda_skb_cb *) skb->cb;
187
188	cb->line = self->line;
189
190	IRDA_DEBUG(4, "%s(), sending frame\n", __func__ );
191
192	/* Don't forget to refcount it - see ircomm_tty_do_softint() */
193	skb_get(skb);
194
195	skb_orphan(skb);
196	skb->destructor = ircomm_lmp_flow_control;
197
198	if ((self->pkt_count++ > 7) && (self->flow_status == FLOW_START)) {
199		IRDA_DEBUG(2, "%s(), asking TTY to slow down!\n", __func__ );
200		self->flow_status = FLOW_STOP;
201		if (self->notify.flow_indication)
202			self->notify.flow_indication(self->notify.instance,
203						     self, FLOW_STOP);
204	}
205	ret = irlmp_data_request(self->lsap, skb);
206	if (ret) {
207		IRDA_ERROR("%s(), failed\n", __func__);
208		/* irlmp_data_request already free the packet */
209	}
210
211	return ret;
212}
213
214/*
215 * Function ircomm_lmp_data_indication (instance, sap, skb)
216 *
217 *    Incoming data which we must deliver to the state machine, to check
218 *    we are still connected.
219 */
220static int ircomm_lmp_data_indication(void *instance, void *sap,
221				      struct sk_buff *skb)
222{
223	struct ircomm_cb *self = (struct ircomm_cb *) instance;
224
225	IRDA_DEBUG(4, "%s()\n", __func__ );
226
227	IRDA_ASSERT(self != NULL, return -1;);
228	IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return -1;);
229	IRDA_ASSERT(skb != NULL, return -1;);
230
231	ircomm_do_event(self, IRCOMM_LMP_DATA_INDICATION, skb, NULL);
232
233	/* Drop reference count - see ircomm_tty_data_indication(). */
234	dev_kfree_skb(skb);
235
236	return 0;
237}
238
239/*
240 * Function ircomm_lmp_connect_confirm (instance, sap, qos, max_sdu_size,
241 *                                       max_header_size, skb)
242 *
243 *    Connection has been confirmed by peer device
244 *
245 */
246static void ircomm_lmp_connect_confirm(void *instance, void *sap,
247				       struct qos_info *qos,
248				       __u32 max_seg_size,
249				       __u8 max_header_size,
250				       struct sk_buff *skb)
251{
252	struct ircomm_cb *self = (struct ircomm_cb *) instance;
253	struct ircomm_info info;
254
255	IRDA_DEBUG(0, "%s()\n", __func__ );
256
257	IRDA_ASSERT(self != NULL, return;);
258	IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
259	IRDA_ASSERT(skb != NULL, return;);
260	IRDA_ASSERT(qos != NULL, return;);
261
262	info.max_data_size = max_seg_size;
263	info.max_header_size = max_header_size;
264	info.qos = qos;
265
266	ircomm_do_event(self, IRCOMM_LMP_CONNECT_CONFIRM, skb, &info);
267
268	/* Drop reference count - see ircomm_tty_connect_confirm(). */
269	dev_kfree_skb(skb);
270}
271
272/*
273 * Function ircomm_lmp_connect_indication (instance, sap, qos, max_sdu_size,
274 *                                         max_header_size, skb)
275 *
276 *    Peer device wants to make a connection with us
277 *
278 */
279static void ircomm_lmp_connect_indication(void *instance, void *sap,
280					  struct qos_info *qos,
281					  __u32 max_seg_size,
282					  __u8 max_header_size,
283					  struct sk_buff *skb)
284{
285	struct ircomm_cb *self = (struct ircomm_cb *)instance;
286	struct ircomm_info info;
287
288	IRDA_DEBUG(0, "%s()\n", __func__ );
289
290	IRDA_ASSERT(self != NULL, return;);
291	IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
292	IRDA_ASSERT(skb != NULL, return;);
293	IRDA_ASSERT(qos != NULL, return;);
294
295	info.max_data_size = max_seg_size;
296	info.max_header_size = max_header_size;
297	info.qos = qos;
298
299	ircomm_do_event(self, IRCOMM_LMP_CONNECT_INDICATION, skb, &info);
300
301	/* Drop reference count - see ircomm_tty_connect_indication(). */
302	dev_kfree_skb(skb);
303}
304
305/*
306 * Function ircomm_lmp_disconnect_indication (instance, sap, reason, skb)
307 *
308 *    Peer device has closed the connection, or the link went down for some
309 *    other reason
310 */
311static void ircomm_lmp_disconnect_indication(void *instance, void *sap,
312					     LM_REASON reason,
313					     struct sk_buff *skb)
314{
315	struct ircomm_cb *self = (struct ircomm_cb *) instance;
316	struct ircomm_info info;
317
318	IRDA_DEBUG(0, "%s()\n", __func__ );
319
320	IRDA_ASSERT(self != NULL, return;);
321	IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
322
323	info.reason = reason;
324
325	ircomm_do_event(self, IRCOMM_LMP_DISCONNECT_INDICATION, skb, &info);
326
327	/* Drop reference count - see ircomm_tty_disconnect_indication(). */
328	if(skb)
329		dev_kfree_skb(skb);
330}
331/*
332 * Function ircomm_open_lsap (self)
333 *
334 *    Open LSAP. This function will only be used when using "raw" services
335 *
336 */
337int ircomm_open_lsap(struct ircomm_cb *self)
338{
339	notify_t notify;
340
341	IRDA_DEBUG(0, "%s()\n", __func__ );
342
343	/* Register callbacks */
344	irda_notify_init(&notify);
345	notify.data_indication       = ircomm_lmp_data_indication;
346	notify.connect_confirm       = ircomm_lmp_connect_confirm;
347	notify.connect_indication    = ircomm_lmp_connect_indication;
348	notify.disconnect_indication = ircomm_lmp_disconnect_indication;
349	notify.instance = self;
350	strlcpy(notify.name, "IrCOMM", sizeof(notify.name));
351
352	self->lsap = irlmp_open_lsap(LSAP_ANY, &notify, 0);
353	if (!self->lsap) {
354		IRDA_DEBUG(0,"%sfailed to allocate tsap\n", __func__ );
355		return -1;
356	}
357	self->slsap_sel = self->lsap->slsap_sel;
358
359	/*
360	 *  Initialize the call-table for issuing commands
361	 */
362	self->issue.data_request       = ircomm_lmp_data_request;
363	self->issue.connect_request    = ircomm_lmp_connect_request;
364	self->issue.connect_response   = ircomm_lmp_connect_response;
365	self->issue.disconnect_request = ircomm_lmp_disconnect_request;
366
367	return 0;
368}
369