08fb54dc8c412cbcb04721ca7df9f034ff06dcbf
[linux-3.10.git] / net / irda / ircomm / ircomm_lmp.c
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, write to the Free Software
28  *     Foundation, Inc., 59 Temple Place, Suite 330, Boston,
29  *     MA 02111-1307 USA
30  *
31  ********************************************************************/
32
33 #include <linux/init.h>
34 #include <linux/gfp.h>
35
36 #include <net/irda/irda.h>
37 #include <net/irda/irlmp.h>
38 #include <net/irda/iriap.h>
39 #include <net/irda/irda_device.h>       /* struct irda_skb_cb */
40
41 #include <net/irda/ircomm_event.h>
42 #include <net/irda/ircomm_lmp.h>
43
44
45 /*
46  * Function ircomm_lmp_connect_request (self, userdata)
47  *
48  *
49  *
50  */
51 static int ircomm_lmp_connect_request(struct ircomm_cb *self,
52                                       struct sk_buff *userdata,
53                                       struct ircomm_info *info)
54 {
55         int ret = 0;
56
57         IRDA_DEBUG(0, "%s()\n", __func__ );
58
59         /* Don't forget to refcount it - should be NULL anyway */
60         if(userdata)
61                 skb_get(userdata);
62
63         ret = irlmp_connect_request(self->lsap, info->dlsap_sel,
64                                     info->saddr, info->daddr, NULL, userdata);
65         return ret;
66 }
67
68 /*
69  * Function ircomm_lmp_connect_response (self, skb)
70  *
71  *
72  *
73  */
74 static int ircomm_lmp_connect_response(struct ircomm_cb *self,
75                                        struct sk_buff *userdata)
76 {
77         struct sk_buff *tx_skb;
78         int ret;
79
80         IRDA_DEBUG(0, "%s()\n", __func__ );
81
82         /* Any userdata supplied? */
83         if (userdata == NULL) {
84                 tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
85                 if (!tx_skb)
86                         return -ENOMEM;
87
88                 /* Reserve space for MUX and LAP header */
89                 skb_reserve(tx_skb, LMP_MAX_HEADER);
90         } else {
91                 /*
92                  *  Check that the client has reserved enough space for
93                  *  headers
94                  */
95                 IRDA_ASSERT(skb_headroom(userdata) >= LMP_MAX_HEADER,
96                             return -1;);
97
98                 /* Don't forget to refcount it - should be NULL anyway */
99                 skb_get(userdata);
100                 tx_skb = userdata;
101         }
102
103         ret = irlmp_connect_response(self->lsap, tx_skb);
104
105         return 0;
106 }
107
108 static int ircomm_lmp_disconnect_request(struct ircomm_cb *self,
109                                          struct sk_buff *userdata,
110                                          struct ircomm_info *info)
111 {
112         struct sk_buff *tx_skb;
113         int ret;
114
115         IRDA_DEBUG(0, "%s()\n", __func__ );
116
117         if (!userdata) {
118                 tx_skb = alloc_skb(LMP_MAX_HEADER, GFP_ATOMIC);
119                 if (!tx_skb)
120                         return -ENOMEM;
121
122                 /*  Reserve space for MUX and LAP header */
123                 skb_reserve(tx_skb, LMP_MAX_HEADER);
124                 userdata = tx_skb;
125         } else {
126                 /* Don't forget to refcount it - should be NULL anyway */
127                 skb_get(userdata);
128         }
129
130         ret = irlmp_disconnect_request(self->lsap, userdata);
131
132         return ret;
133 }
134
135 /*
136  * Function ircomm_lmp_flow_control (skb)
137  *
138  *    This function is called when a data frame we have sent to IrLAP has
139  *    been deallocated. We do this to make sure we don't flood IrLAP with
140  *    frames, since we are not using the IrTTP flow control mechanism
141  */
142 static void ircomm_lmp_flow_control(struct sk_buff *skb)
143 {
144         struct irda_skb_cb *cb;
145         struct ircomm_cb *self;
146         int line;
147
148         IRDA_ASSERT(skb != NULL, return;);
149
150         cb = (struct irda_skb_cb *) skb->cb;
151
152         IRDA_DEBUG(2, "%s()\n", __func__ );
153
154         line = cb->line;
155
156         self = (struct ircomm_cb *) hashbin_lock_find(ircomm, line, NULL);
157         if (!self) {
158                 IRDA_DEBUG(2, "%s(), didn't find myself\n", __func__ );
159                 return;
160         }
161
162         IRDA_ASSERT(self != NULL, return;);
163         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
164
165         self->pkt_count--;
166
167         if ((self->pkt_count < 2) && (self->flow_status == FLOW_STOP)) {
168                 IRDA_DEBUG(2, "%s(), asking TTY to start again!\n", __func__ );
169                 self->flow_status = FLOW_START;
170                 if (self->notify.flow_indication)
171                         self->notify.flow_indication(self->notify.instance,
172                                                      self, FLOW_START);
173         }
174 }
175
176 /*
177  * Function ircomm_lmp_data_request (self, userdata)
178  *
179  *    Send data frame to peer device
180  *
181  */
182 static int ircomm_lmp_data_request(struct ircomm_cb *self,
183                                    struct sk_buff *skb,
184                                    int not_used)
185 {
186         struct irda_skb_cb *cb;
187         int ret;
188
189         IRDA_ASSERT(skb != NULL, return -1;);
190
191         cb = (struct irda_skb_cb *) skb->cb;
192
193         cb->line = self->line;
194
195         IRDA_DEBUG(4, "%s(), sending frame\n", __func__ );
196
197         /* Don't forget to refcount it - see ircomm_tty_do_softint() */
198         skb_get(skb);
199
200         skb_orphan(skb);
201         skb->destructor = ircomm_lmp_flow_control;
202
203         if ((self->pkt_count++ > 7) && (self->flow_status == FLOW_START)) {
204                 IRDA_DEBUG(2, "%s(), asking TTY to slow down!\n", __func__ );
205                 self->flow_status = FLOW_STOP;
206                 if (self->notify.flow_indication)
207                         self->notify.flow_indication(self->notify.instance,
208                                                      self, FLOW_STOP);
209         }
210         ret = irlmp_data_request(self->lsap, skb);
211         if (ret) {
212                 IRDA_ERROR("%s(), failed\n", __func__);
213                 /* irlmp_data_request already free the packet */
214         }
215
216         return ret;
217 }
218
219 /*
220  * Function ircomm_lmp_data_indication (instance, sap, skb)
221  *
222  *    Incoming data which we must deliver to the state machine, to check
223  *    we are still connected.
224  */
225 static int ircomm_lmp_data_indication(void *instance, void *sap,
226                                       struct sk_buff *skb)
227 {
228         struct ircomm_cb *self = (struct ircomm_cb *) instance;
229
230         IRDA_DEBUG(4, "%s()\n", __func__ );
231
232         IRDA_ASSERT(self != NULL, return -1;);
233         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return -1;);
234         IRDA_ASSERT(skb != NULL, return -1;);
235
236         ircomm_do_event(self, IRCOMM_LMP_DATA_INDICATION, skb, NULL);
237
238         /* Drop reference count - see ircomm_tty_data_indication(). */
239         dev_kfree_skb(skb);
240
241         return 0;
242 }
243
244 /*
245  * Function ircomm_lmp_connect_confirm (instance, sap, qos, max_sdu_size,
246  *                                       max_header_size, skb)
247  *
248  *    Connection has been confirmed by peer device
249  *
250  */
251 static void ircomm_lmp_connect_confirm(void *instance, void *sap,
252                                        struct qos_info *qos,
253                                        __u32 max_seg_size,
254                                        __u8 max_header_size,
255                                        struct sk_buff *skb)
256 {
257         struct ircomm_cb *self = (struct ircomm_cb *) instance;
258         struct ircomm_info info;
259
260         IRDA_DEBUG(0, "%s()\n", __func__ );
261
262         IRDA_ASSERT(self != NULL, return;);
263         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
264         IRDA_ASSERT(skb != NULL, return;);
265         IRDA_ASSERT(qos != NULL, return;);
266
267         info.max_data_size = max_seg_size;
268         info.max_header_size = max_header_size;
269         info.qos = qos;
270
271         ircomm_do_event(self, IRCOMM_LMP_CONNECT_CONFIRM, skb, &info);
272
273         /* Drop reference count - see ircomm_tty_connect_confirm(). */
274         dev_kfree_skb(skb);
275 }
276
277 /*
278  * Function ircomm_lmp_connect_indication (instance, sap, qos, max_sdu_size,
279  *                                         max_header_size, skb)
280  *
281  *    Peer device wants to make a connection with us
282  *
283  */
284 static void ircomm_lmp_connect_indication(void *instance, void *sap,
285                                           struct qos_info *qos,
286                                           __u32 max_seg_size,
287                                           __u8 max_header_size,
288                                           struct sk_buff *skb)
289 {
290         struct ircomm_cb *self = (struct ircomm_cb *)instance;
291         struct ircomm_info info;
292
293         IRDA_DEBUG(0, "%s()\n", __func__ );
294
295         IRDA_ASSERT(self != NULL, return;);
296         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
297         IRDA_ASSERT(skb != NULL, return;);
298         IRDA_ASSERT(qos != NULL, return;);
299
300         info.max_data_size = max_seg_size;
301         info.max_header_size = max_header_size;
302         info.qos = qos;
303
304         ircomm_do_event(self, IRCOMM_LMP_CONNECT_INDICATION, skb, &info);
305
306         /* Drop reference count - see ircomm_tty_connect_indication(). */
307         dev_kfree_skb(skb);
308 }
309
310 /*
311  * Function ircomm_lmp_disconnect_indication (instance, sap, reason, skb)
312  *
313  *    Peer device has closed the connection, or the link went down for some
314  *    other reason
315  */
316 static void ircomm_lmp_disconnect_indication(void *instance, void *sap,
317                                              LM_REASON reason,
318                                              struct sk_buff *skb)
319 {
320         struct ircomm_cb *self = (struct ircomm_cb *) instance;
321         struct ircomm_info info;
322
323         IRDA_DEBUG(0, "%s()\n", __func__ );
324
325         IRDA_ASSERT(self != NULL, return;);
326         IRDA_ASSERT(self->magic == IRCOMM_MAGIC, return;);
327
328         info.reason = reason;
329
330         ircomm_do_event(self, IRCOMM_LMP_DISCONNECT_INDICATION, skb, &info);
331
332         /* Drop reference count - see ircomm_tty_disconnect_indication(). */
333         if(skb)
334                 dev_kfree_skb(skb);
335 }
336 /*
337  * Function ircomm_open_lsap (self)
338  *
339  *    Open LSAP. This function will only be used when using "raw" services
340  *
341  */
342 int ircomm_open_lsap(struct ircomm_cb *self)
343 {
344         notify_t notify;
345
346         IRDA_DEBUG(0, "%s()\n", __func__ );
347
348         /* Register callbacks */
349         irda_notify_init(&notify);
350         notify.data_indication       = ircomm_lmp_data_indication;
351         notify.connect_confirm       = ircomm_lmp_connect_confirm;
352         notify.connect_indication    = ircomm_lmp_connect_indication;
353         notify.disconnect_indication = ircomm_lmp_disconnect_indication;
354         notify.instance = self;
355         strlcpy(notify.name, "IrCOMM", sizeof(notify.name));
356
357         self->lsap = irlmp_open_lsap(LSAP_ANY, &notify, 0);
358         if (!self->lsap) {
359                 IRDA_DEBUG(0,"%sfailed to allocate tsap\n", __func__ );
360                 return -1;
361         }
362         self->slsap_sel = self->lsap->slsap_sel;
363
364         /*
365          *  Initialize the call-table for issuing commands
366          */
367         self->issue.data_request       = ircomm_lmp_data_request;
368         self->issue.connect_request    = ircomm_lmp_connect_request;
369         self->issue.connect_response   = ircomm_lmp_connect_response;
370         self->issue.disconnect_request = ircomm_lmp_disconnect_request;
371
372         return 0;
373 }