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/* $Id: isdn_concap.c,v 1.1.4.1 2001/11/20 14:19:34 kai Exp $
*
* Linux ISDN subsystem, protocol encapsulation
*
* This software may be used and distributed according to the terms
* of the GNU General Public License, incorporated herein by reference.
*
*/
/* Stuff to support the concap_proto by isdn4linux. isdn4linux - specific
* stuff goes here. Stuff that depends only on the concap protocol goes to
* another -- protocol specific -- source file.
*
*/
#include <linux/isdn.h>
#include "isdn_x25iface.h"
#include "isdn_net.h"
#include <linux/concap.h>
#include "isdn_concap.h"
/* The following set of device service operations are for encapsulation
protocols that require for reliable datalink semantics. That means:
- before any data is to be submitted the connection must explicitly
be set up.
- after the successful set up of the connection is signalled the
connection is considered to be reliably up.
Auto-dialing ist not compatible with this requirements. Thus, auto-dialing
is completely bypassed.
It might be possible to implement a (non standardized) datalink protocol
that provides a reliable data link service while using some auto dialing
mechanism. Such a protocol would need an auxiliary channel (i.e. user-user-
signaling on the D-channel) while the B-channel is down.
*/
int isdn_concap_dl_data_req(struct concap_proto *concap, struct sk_buff *skb)
{
struct net_device *ndev = concap -> net_dev;
isdn_net_dev *nd = ((isdn_net_local *) ndev->priv)->netdev;
isdn_net_local *lp = isdn_net_get_locked_lp(nd);
IX25DEBUG( "isdn_concap_dl_data_req: %s \n", concap->net_dev->name);
if (!lp) {
IX25DEBUG( "isdn_concap_dl_data_req: %s : isdn_net_send_skb returned %d\n", concap -> net_dev -> name, 1);
return 1;
}
lp->huptimer = 0;
isdn_net_writebuf_skb(lp, skb);
spin_unlock_bh(&lp->xmit_lock);
IX25DEBUG( "isdn_concap_dl_data_req: %s : isdn_net_send_skb returned %d\n", concap -> net_dev -> name, 0);
return 0;
}
int isdn_concap_dl_connect_req(struct concap_proto *concap)
{
struct net_device *ndev = concap -> net_dev;
isdn_net_local *lp = (isdn_net_local *) ndev->priv;
int ret;
IX25DEBUG( "isdn_concap_dl_connect_req: %s \n", ndev -> name);
/* dial ... */
ret = isdn_net_dial_req( lp );
if ( ret ) IX25DEBUG("dialing failed\n");
return ret;
}
int isdn_concap_dl_disconn_req(struct concap_proto *concap)
{
IX25DEBUG( "isdn_concap_dl_disconn_req: %s \n", concap -> net_dev -> name);
isdn_net_hangup( concap -> net_dev );
return 0;
}
struct concap_device_ops isdn_concap_reliable_dl_dops = {
&isdn_concap_dl_data_req,
&isdn_concap_dl_connect_req,
&isdn_concap_dl_disconn_req
};
struct concap_device_ops isdn_concap_demand_dial_dops = {
NULL, /* set this first entry to something like &isdn_net_start_xmit,
but the entry part of the current isdn_net_start_xmit must be
separated first. */
/* no connection control for demand dial semantics */
NULL,
NULL,
};
/* The following should better go into a dedicated source file such that
this sourcefile does not need to include any protocol specific header
files. For now:
*/
struct concap_proto * isdn_concap_new( int encap )
{
switch ( encap ) {
case ISDN_NET_ENCAP_X25IFACE:
return isdn_x25iface_proto_new();
}
return NULL;
}
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