1 /* $Id: isdn_concap.c,v 1.1.4.1 2001/11/20 14:19:34 kai Exp $
2 *
3 * Linux ISDN subsystem, protocol encapsulation
4 *
5 * This software may be used and distributed according to the terms
6 * of the GNU General Public License, incorporated herein by reference.
7 *
8 */
9
10 /* Stuff to support the concap_proto by isdn4linux. isdn4linux - specific
11 * stuff goes here. Stuff that depends only on the concap protocol goes to
12 * another -- protocol specific -- source file.
13 *
14 */
15
16
17 #include <linux/isdn.h>
18 #include "isdn_x25iface.h"
19 #include "isdn_net.h"
20 #include <linux/concap.h>
21 #include "isdn_concap.h"
22
23
24 /* The following set of device service operations are for encapsulation
25 protocols that require for reliable datalink semantics. That means:
26
27 - before any data is to be submitted the connection must explicitly
28 be set up.
29 - after the successful set up of the connection is signalled the
30 connection is considered to be reliably up.
31
32 Auto-dialing ist not compatible with this requirements. Thus, auto-dialing
33 is completely bypassed.
34
35 It might be possible to implement a (non standardized) datalink protocol
36 that provides a reliable data link service while using some auto dialing
37 mechanism. Such a protocol would need an auxiliary channel (i.e. user-user-
38 signaling on the D-channel) while the B-channel is down.
39 */
40
41
isdn_concap_dl_data_req(struct concap_proto * concap,struct sk_buff * skb)42 int isdn_concap_dl_data_req(struct concap_proto *concap, struct sk_buff *skb)
43 {
44 struct net_device *ndev = concap -> net_dev;
45 isdn_net_dev *nd = ((isdn_net_local *) ndev->priv)->netdev;
46 isdn_net_local *lp = isdn_net_get_locked_lp(nd);
47
48 IX25DEBUG( "isdn_concap_dl_data_req: %s \n", concap->net_dev->name);
49 if (!lp) {
50 IX25DEBUG( "isdn_concap_dl_data_req: %s : isdn_net_send_skb returned %d\n", concap -> net_dev -> name, 1);
51 return 1;
52 }
53 lp->huptimer = 0;
54 isdn_net_writebuf_skb(lp, skb);
55 spin_unlock_bh(&lp->xmit_lock);
56 IX25DEBUG( "isdn_concap_dl_data_req: %s : isdn_net_send_skb returned %d\n", concap -> net_dev -> name, 0);
57 return 0;
58 }
59
60
isdn_concap_dl_connect_req(struct concap_proto * concap)61 int isdn_concap_dl_connect_req(struct concap_proto *concap)
62 {
63 struct net_device *ndev = concap -> net_dev;
64 isdn_net_local *lp = (isdn_net_local *) ndev->priv;
65 int ret;
66 IX25DEBUG( "isdn_concap_dl_connect_req: %s \n", ndev -> name);
67
68 /* dial ... */
69 ret = isdn_net_dial_req( lp );
70 if ( ret ) IX25DEBUG("dialing failed\n");
71 return ret;
72 }
73
isdn_concap_dl_disconn_req(struct concap_proto * concap)74 int isdn_concap_dl_disconn_req(struct concap_proto *concap)
75 {
76 IX25DEBUG( "isdn_concap_dl_disconn_req: %s \n", concap -> net_dev -> name);
77
78 isdn_net_hangup( concap -> net_dev );
79 return 0;
80 }
81
82 struct concap_device_ops isdn_concap_reliable_dl_dops = {
83 &isdn_concap_dl_data_req,
84 &isdn_concap_dl_connect_req,
85 &isdn_concap_dl_disconn_req
86 };
87
88 struct concap_device_ops isdn_concap_demand_dial_dops = {
89 NULL, /* set this first entry to something like &isdn_net_start_xmit,
90 but the entry part of the current isdn_net_start_xmit must be
91 separated first. */
92 /* no connection control for demand dial semantics */
93 NULL,
94 NULL,
95 };
96
97 /* The following should better go into a dedicated source file such that
98 this sourcefile does not need to include any protocol specific header
99 files. For now:
100 */
isdn_concap_new(int encap)101 struct concap_proto * isdn_concap_new( int encap )
102 {
103 switch ( encap ) {
104 case ISDN_NET_ENCAP_X25IFACE:
105 return isdn_x25iface_proto_new();
106 }
107 return NULL;
108 }
109