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/* $Id: isdn_concap.c,v 1.1.2.2 2004/01/12 22:37:19 keil 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. */ static 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; } static 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; } static 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 }; /* 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; } |