summaryrefslogblamecommitdiffstats
path: root/drivers/isdn/mISDN/layer2.c
blob: 68a4815167293300825eb2003f3c7d9d2596f379 (plain) (tree)
1
2
3
4
5
6
7
8
9
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
                                        




                                                     

   
                          
                       
                 


                   
                    



































                                            

                    




                             
                                              





















                                 

                      








                                             
                             



                                     
 
                          



                      

                                                                  
 








































                                                                     

                                                                    



















                                                              
                                            

                                        

                                                                    









                                                    

                                                                 









































                                                                          
                                            














































                                                                               








                                                    


                                                                            





                                                                           


                                                                           



                                                          



                                                 

                                                                 
                                            
                                                  























































                                                                        
                                                                    

































































































































                                                                        
                                                        

 
          
















                                                                       
          







                                                      
          











                                                                
          











                                                       
          














                                                  

                                                                                    




                                           

                                                                 


















































                                                                              

                                                                             


                               
                                  

























































































































































































































































































































































































































































                                                                            
                                                             





















                                                           
           













                                                                 

                                                                            

                       
                                  






















































                                                                               
                                                                    
                                                                     















































                                                                  
                                                                   




                                                                            
                                                                   
































































































                                                                            
                                                                           






































                                                                  
                                                  







                                                                            
                                                             






                                                                            
                                                                  








                                                         
                                                  










                                                                            
                                           









                                                         
                                                  















                                                                            
                                                  



















                                                                            
                                                  











                                                                            
                                    








                                                 



                                              










                                                                            

                                            
                                           

                                          




                                                                                
         

                                             










































                                                                             
                                                                       





































































































                                                                            
                                                               












                                                          
                                                              















                                                   
                                                              












                                                   
                                                          































































































































                                                              









                                                









                                                           
                                                           

                                                        




                                                           

  


















                                                                                

                                                                       




                                        
                                              

                                                                              

                                                                       



                                                               
                                              

                                                                             
                                                                                







































                                                                         

                                                                       









                                                                             
                                              

                                   


                                                                              





                                                                               
                                                                            
         











                                                                  
                                                                          





















                                                                       
                                                          
                                                              
                                                                                  

                                                            
                                                            
                                                                
                                                            

                                                                       
                                          




                                                            
                                                             
                                                                    
                                          
                      





                                                            


                                                                 
                                            













                                                

                                                                











                                                                              

                                                                  















                                                                      
                               

                                                                  
                                                                    










                                                                          

                                                           






                                                                        
                                                         











                                                                            
                                                                           
                   



















                                                           
                                








                                                                   
                              













                                                                              
                                








                                                                   
                              





















                                                                              
                                 









                                             
                                                 
                                              



















                                                
                                                        















                                                               
                





                                           





                                                                   
                 





                                            








                                            
// SPDX-License-Identifier: GPL-2.0-only
/*
 *
 * Author	Karsten Keil <kkeil@novell.com>
 *
 * Copyright 2008  by Karsten Keil <kkeil@novell.com>
 */

#include <linux/mISDNif.h>
#include <linux/slab.h>
#include "core.h"
#include "fsm.h"
#include "layer2.h"

static u_int *debug;

static
struct Fsm l2fsm = {NULL, 0, 0, NULL, NULL};

static char *strL2State[] =
{
	"ST_L2_1",
	"ST_L2_2",
	"ST_L2_3",
	"ST_L2_4",
	"ST_L2_5",
	"ST_L2_6",
	"ST_L2_7",
	"ST_L2_8",
};

enum {
	EV_L2_UI,
	EV_L2_SABME,
	EV_L2_DISC,
	EV_L2_DM,
	EV_L2_UA,
	EV_L2_FRMR,
	EV_L2_SUPER,
	EV_L2_I,
	EV_L2_DL_DATA,
	EV_L2_ACK_PULL,
	EV_L2_DL_UNITDATA,
	EV_L2_DL_ESTABLISH_REQ,
	EV_L2_DL_RELEASE_REQ,
	EV_L2_MDL_ASSIGN,
	EV_L2_MDL_REMOVE,
	EV_L2_MDL_ERROR,
	EV_L1_DEACTIVATE,
	EV_L2_T200,
	EV_L2_T203,
	EV_L2_T200I,
	EV_L2_T203I,
	EV_L2_SET_OWN_BUSY,
	EV_L2_CLEAR_OWN_BUSY,
	EV_L2_FRAME_ERROR,
};

#define L2_EVENT_COUNT (EV_L2_FRAME_ERROR + 1)

static char *strL2Event[] =
{
	"EV_L2_UI",
	"EV_L2_SABME",
	"EV_L2_DISC",
	"EV_L2_DM",
	"EV_L2_UA",
	"EV_L2_FRMR",
	"EV_L2_SUPER",
	"EV_L2_I",
	"EV_L2_DL_DATA",
	"EV_L2_ACK_PULL",
	"EV_L2_DL_UNITDATA",
	"EV_L2_DL_ESTABLISH_REQ",
	"EV_L2_DL_RELEASE_REQ",
	"EV_L2_MDL_ASSIGN",
	"EV_L2_MDL_REMOVE",
	"EV_L2_MDL_ERROR",
	"EV_L1_DEACTIVATE",
	"EV_L2_T200",
	"EV_L2_T203",
	"EV_L2_T200I",
	"EV_L2_T203I",
	"EV_L2_SET_OWN_BUSY",
	"EV_L2_CLEAR_OWN_BUSY",
	"EV_L2_FRAME_ERROR",
};

static void
l2m_debug(struct FsmInst *fi, char *fmt, ...)
{
	struct layer2 *l2 = fi->userdata;
	struct va_format vaf;
	va_list va;

	if (!(*debug & DEBUG_L2_FSM))
		return;

	va_start(va, fmt);

	vaf.fmt = fmt;
	vaf.va = &va;

	printk(KERN_DEBUG "%s l2 (sapi %d tei %d): %pV\n",
	       mISDNDevName4ch(&l2->ch), l2->sapi, l2->tei, &vaf);

	va_end(va);
}

inline u_int
l2headersize(struct layer2 *l2, int ui)
{
	return ((test_bit(FLG_MOD128, &l2->flag) && (!ui)) ? 2 : 1) +
		(test_bit(FLG_LAPD, &l2->flag) ? 2 : 1);
}

inline u_int
l2addrsize(struct layer2 *l2)
{
	return test_bit(FLG_LAPD, &l2->flag) ? 2 : 1;
}

static u_int
l2_newid(struct layer2 *l2)
{
	u_int	id;

	id = l2->next_id++;
	if (id == 0x7fff)
		l2->next_id = 1;
	id <<= 16;
	id |= l2->tei << 8;
	id |= l2->sapi;
	return id;
}

static void
l2up(struct layer2 *l2, u_int prim, struct sk_buff *skb)
{
	int	err;

	if (!l2->up)
		return;
	mISDN_HEAD_PRIM(skb) = prim;
	mISDN_HEAD_ID(skb) = (l2->ch.nr << 16) | l2->ch.addr;
	err = l2->up->send(l2->up, skb);
	if (err) {
		printk(KERN_WARNING "%s: dev %s err=%d\n", __func__,
		       mISDNDevName4ch(&l2->ch), err);
		dev_kfree_skb(skb);
	}
}

static void
l2up_create(struct layer2 *l2, u_int prim, int len, void *arg)
{
	struct sk_buff	*skb;
	struct mISDNhead *hh;
	int		err;

	if (!l2->up)
		return;
	skb = mI_alloc_skb(len, GFP_ATOMIC);
	if (!skb)
		return;
	hh = mISDN_HEAD_P(skb);
	hh->prim = prim;
	hh->id = (l2->ch.nr << 16) | l2->ch.addr;
	if (len)
		skb_put_data(skb, arg, len);
	err = l2->up->send(l2->up, skb);
	if (err) {
		printk(KERN_WARNING "%s: dev %s err=%d\n", __func__,
		       mISDNDevName4ch(&l2->ch), err);
		dev_kfree_skb(skb);
	}
}

static int
l2down_skb(struct layer2 *l2, struct sk_buff *skb) {
	int ret;

	ret = l2->ch.recv(l2->ch.peer, skb);
	if (ret && (*debug & DEBUG_L2_RECV))
		printk(KERN_DEBUG "l2down_skb: dev %s ret(%d)\n",
		       mISDNDevName4ch(&l2->ch), ret);
	return ret;
}

static int
l2down_raw(struct layer2 *l2, struct sk_buff *skb)
{
	struct mISDNhead *hh = mISDN_HEAD_P(skb);

	if (hh->prim == PH_DATA_REQ) {
		if (test_and_set_bit(FLG_L1_NOTREADY, &l2->flag)) {
			skb_queue_tail(&l2->down_queue, skb);
			return 0;
		}
		l2->down_id = mISDN_HEAD_ID(skb);
	}
	return l2down_skb(l2, skb);
}

static int
l2down(struct layer2 *l2, u_int prim, u_int id, struct sk_buff *skb)
{
	struct mISDNhead *hh = mISDN_HEAD_P(skb);

	hh->prim = prim;
	hh->id = id;
	return l2down_raw(l2, skb);
}

static int
l2down_create(struct layer2 *l2, u_int prim, u_int id, int len, void *arg)
{
	struct sk_buff	*skb;
	int		err;
	struct mISDNhead *hh;

	skb = mI_alloc_skb(len, GFP_ATOMIC);
	if (!skb)
		return -ENOMEM;
	hh = mISDN_HEAD_P(skb);
	hh->prim = prim;
	hh->id = id;
	if (len)
		skb_put_data(skb, arg, len);
	err = l2down_raw(l2, skb);
	if (err)
		dev_kfree_skb(skb);
	return err;
}

static int
ph_data_confirm(struct layer2 *l2, struct mISDNhead *hh, struct sk_buff *skb) {
	struct sk_buff *nskb = skb;
	int ret = -EAGAIN;

	if (test_bit(FLG_L1_NOTREADY, &l2->flag)) {
		if (hh->id == l2->down_id) {
			nskb = skb_dequeue(&l2->down_queue);
			if (nskb) {
				l2->down_id = mISDN_HEAD_ID(nskb);
				if (l2down_skb(l2, nskb)) {
					dev_kfree_skb(nskb);
					l2->down_id = MISDN_ID_NONE;
				}
			} else
				l2->down_id = MISDN_ID_NONE;
			if (ret) {
				dev_kfree_skb(skb);
				ret = 0;
			}
			if (l2->down_id == MISDN_ID_NONE) {
				test_and_clear_bit(FLG_L1_NOTREADY, &l2->flag);
				mISDN_FsmEvent(&l2->l2m, EV_L2_ACK_PULL, NULL);
			}
		}
	}
	if (!test_and_set_bit(FLG_L1_NOTREADY, &l2->flag)) {
		nskb = skb_dequeue(&l2->down_queue);
		if (nskb) {
			l2->down_id = mISDN_HEAD_ID(nskb);
			if (l2down_skb(l2, nskb)) {
				dev_kfree_skb(nskb);
				l2->down_id = MISDN_ID_NONE;
				test_and_clear_bit(FLG_L1_NOTREADY, &l2->flag);
			}
		} else
			test_and_clear_bit(FLG_L1_NOTREADY, &l2->flag);
	}
	return ret;
}

static void
l2_timeout(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb;
	struct mISDNhead *hh;

	skb = mI_alloc_skb(0, GFP_ATOMIC);
	if (!skb) {
		printk(KERN_WARNING "%s: L2(%d,%d) nr:%x timer %s no skb\n",
		       mISDNDevName4ch(&l2->ch), l2->sapi, l2->tei,
		       l2->ch.nr, event == EV_L2_T200 ? "T200" : "T203");
		return;
	}
	hh = mISDN_HEAD_P(skb);
	hh->prim = event == EV_L2_T200 ? DL_TIMER200_IND : DL_TIMER203_IND;
	hh->id = l2->ch.nr;
	if (*debug & DEBUG_TIMER)
		printk(KERN_DEBUG "%s: L2(%d,%d) nr:%x timer %s expired\n",
		       mISDNDevName4ch(&l2->ch), l2->sapi, l2->tei,
		       l2->ch.nr, event == EV_L2_T200 ? "T200" : "T203");
	if (l2->ch.st)
		l2->ch.st->own.recv(&l2->ch.st->own, skb);
}

static int
l2mgr(struct layer2 *l2, u_int prim, void *arg) {
	long c = (long)arg;

	printk(KERN_WARNING "l2mgr: dev %s addr:%x prim %x %c\n",
	       mISDNDevName4ch(&l2->ch), l2->id, prim, (char)c);
	if (test_bit(FLG_LAPD, &l2->flag) &&
	    !test_bit(FLG_FIXED_TEI, &l2->flag)) {
		switch (c) {
		case 'C':
		case 'D':
		case 'G':
		case 'H':
			l2_tei(l2, prim, (u_long)arg);
			break;
		}
	}
	return 0;
}

static void
set_peer_busy(struct layer2 *l2) {
	test_and_set_bit(FLG_PEER_BUSY, &l2->flag);
	if (skb_queue_len(&l2->i_queue) || skb_queue_len(&l2->ui_queue))
		test_and_set_bit(FLG_L2BLOCK, &l2->flag);
}

static void
clear_peer_busy(struct layer2 *l2) {
	if (test_and_clear_bit(FLG_PEER_BUSY, &l2->flag))
		test_and_clear_bit(FLG_L2BLOCK, &l2->flag);
}

static void
InitWin(struct layer2 *l2)
{
	int i;

	for (i = 0; i < MAX_WINDOW; i++)
		l2->windowar[i] = NULL;
}

static int
freewin(struct layer2 *l2)
{
	int i, cnt = 0;

	for (i = 0; i < MAX_WINDOW; i++) {
		if (l2->windowar[i]) {
			cnt++;
			dev_kfree_skb(l2->windowar[i]);
			l2->windowar[i] = NULL;
		}
	}
	return cnt;
}

static void
ReleaseWin(struct layer2 *l2)
{
	int cnt = freewin(l2);

	if (cnt)
		printk(KERN_WARNING
		       "isdnl2 freed %d skbuffs in release\n", cnt);
}

inline unsigned int
cansend(struct layer2 *l2)
{
	unsigned int p1;

	if (test_bit(FLG_MOD128, &l2->flag))
		p1 = (l2->vs - l2->va) % 128;
	else
		p1 = (l2->vs - l2->va) % 8;
	return (p1 < l2->window) && !test_bit(FLG_PEER_BUSY, &l2->flag);
}

inline void
clear_exception(struct layer2 *l2)
{
	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
	test_and_clear_bit(FLG_REJEXC, &l2->flag);
	test_and_clear_bit(FLG_OWN_BUSY, &l2->flag);
	clear_peer_busy(l2);
}

static int
sethdraddr(struct layer2 *l2, u_char *header, int rsp)
{
	u_char *ptr = header;
	int crbit = rsp;

	if (test_bit(FLG_LAPD, &l2->flag)) {
		if (test_bit(FLG_LAPD_NET, &l2->flag))
			crbit = !crbit;
		*ptr++ = (l2->sapi << 2) | (crbit ? 2 : 0);
		*ptr++ = (l2->tei << 1) | 1;
		return 2;
	} else {
		if (test_bit(FLG_ORIG, &l2->flag))
			crbit = !crbit;
		if (crbit)
			*ptr++ = l2->addr.B;
		else
			*ptr++ = l2->addr.A;
		return 1;
	}
}

static inline void
enqueue_super(struct layer2 *l2, struct sk_buff *skb)
{
	if (l2down(l2, PH_DATA_REQ, l2_newid(l2), skb))
		dev_kfree_skb(skb);
}

static inline void
enqueue_ui(struct layer2 *l2, struct sk_buff *skb)
{
	if (l2->tm)
		l2_tei(l2, MDL_STATUS_UI_IND, 0);
	if (l2down(l2, PH_DATA_REQ, l2_newid(l2), skb))
		dev_kfree_skb(skb);
}

inline int
IsUI(u_char *data)
{
	return (data[0] & 0xef) == UI;
}

inline int
IsUA(u_char *data)
{
	return (data[0] & 0xef) == UA;
}

inline int
IsDM(u_char *data)
{
	return (data[0] & 0xef) == DM;
}

inline int
IsDISC(u_char *data)
{
	return (data[0] & 0xef) == DISC;
}

inline int
IsRR(u_char *data, struct layer2 *l2)
{
	if (test_bit(FLG_MOD128, &l2->flag))
		return data[0] == RR;
	else
		return (data[0] & 0xf) == 1;
}

inline int
IsSFrame(u_char *data, struct layer2 *l2)
{
	register u_char d = *data;

	if (!test_bit(FLG_MOD128, &l2->flag))
		d &= 0xf;
	return ((d & 0xf3) == 1) && ((d & 0x0c) != 0x0c);
}

inline int
IsSABME(u_char *data, struct layer2 *l2)
{
	u_char d = data[0] & ~0x10;

	return test_bit(FLG_MOD128, &l2->flag) ? d == SABME : d == SABM;
}

inline int
IsREJ(u_char *data, struct layer2 *l2)
{
	return test_bit(FLG_MOD128, &l2->flag) ?
		data[0] == REJ : (data[0] & 0xf) == REJ;
}

inline int
IsFRMR(u_char *data)
{
	return (data[0] & 0xef) == FRMR;
}

inline int
IsRNR(u_char *data, struct layer2 *l2)
{
	return test_bit(FLG_MOD128, &l2->flag) ?
		data[0] == RNR : (data[0] & 0xf) == RNR;
}

static int
iframe_error(struct layer2 *l2, struct sk_buff *skb)
{
	u_int	i;
	int	rsp = *skb->data & 0x2;

	i = l2addrsize(l2) + (test_bit(FLG_MOD128, &l2->flag) ? 2 : 1);
	if (test_bit(FLG_ORIG, &l2->flag))
		rsp = !rsp;
	if (rsp)
		return 'L';
	if (skb->len < i)
		return 'N';
	if ((skb->len - i) > l2->maxlen)
		return 'O';
	return 0;
}

static int
super_error(struct layer2 *l2, struct sk_buff *skb)
{
	if (skb->len != l2addrsize(l2) +
	    (test_bit(FLG_MOD128, &l2->flag) ? 2 : 1))
		return 'N';
	return 0;
}

static int
unnum_error(struct layer2 *l2, struct sk_buff *skb, int wantrsp)
{
	int rsp = (*skb->data & 0x2) >> 1;
	if (test_bit(FLG_ORIG, &l2->flag))
		rsp = !rsp;
	if (rsp != wantrsp)
		return 'L';
	if (skb->len != l2addrsize(l2) + 1)
		return 'N';
	return 0;
}

static int
UI_error(struct layer2 *l2, struct sk_buff *skb)
{
	int rsp = *skb->data & 0x2;
	if (test_bit(FLG_ORIG, &l2->flag))
		rsp = !rsp;
	if (rsp)
		return 'L';
	if (skb->len > l2->maxlen + l2addrsize(l2) + 1)
		return 'O';
	return 0;
}

static int
FRMR_error(struct layer2 *l2, struct sk_buff *skb)
{
	u_int	headers = l2addrsize(l2) + 1;
	u_char	*datap = skb->data + headers;
	int	rsp = *skb->data & 0x2;

	if (test_bit(FLG_ORIG, &l2->flag))
		rsp = !rsp;
	if (!rsp)
		return 'L';
	if (test_bit(FLG_MOD128, &l2->flag)) {
		if (skb->len < headers + 5)
			return 'N';
		else if (*debug & DEBUG_L2)
			l2m_debug(&l2->l2m,
				  "FRMR information %2x %2x %2x %2x %2x",
				  datap[0], datap[1], datap[2], datap[3], datap[4]);
	} else {
		if (skb->len < headers + 3)
			return 'N';
		else if (*debug & DEBUG_L2)
			l2m_debug(&l2->l2m,
				  "FRMR information %2x %2x %2x",
				  datap[0], datap[1], datap[2]);
	}
	return 0;
}

static unsigned int
legalnr(struct layer2 *l2, unsigned int nr)
{
	if (test_bit(FLG_MOD128, &l2->flag))
		return ((nr - l2->va) % 128) <= ((l2->vs - l2->va) % 128);
	else
		return ((nr - l2->va) % 8) <= ((l2->vs - l2->va) % 8);
}

static void
setva(struct layer2 *l2, unsigned int nr)
{
	struct sk_buff	*skb;

	while (l2->va != nr) {
		l2->va++;
		if (test_bit(FLG_MOD128, &l2->flag))
			l2->va %= 128;
		else
			l2->va %= 8;
		if (l2->windowar[l2->sow]) {
			skb_trim(l2->windowar[l2->sow], 0);
			skb_queue_tail(&l2->tmp_queue, l2->windowar[l2->sow]);
			l2->windowar[l2->sow] = NULL;
		}
		l2->sow = (l2->sow + 1) % l2->window;
	}
	skb = skb_dequeue(&l2->tmp_queue);
	while (skb) {
		dev_kfree_skb(skb);
		skb = skb_dequeue(&l2->tmp_queue);
	}
}

static void
send_uframe(struct layer2 *l2, struct sk_buff *skb, u_char cmd, u_char cr)
{
	u_char tmp[MAX_L2HEADER_LEN];
	int i;

	i = sethdraddr(l2, tmp, cr);
	tmp[i++] = cmd;
	if (skb)
		skb_trim(skb, 0);
	else {
		skb = mI_alloc_skb(i, GFP_ATOMIC);
		if (!skb) {
			printk(KERN_WARNING "%s: can't alloc skbuff in %s\n",
			       mISDNDevName4ch(&l2->ch), __func__);
			return;
		}
	}
	skb_put_data(skb, tmp, i);
	enqueue_super(l2, skb);
}


inline u_char
get_PollFlag(struct layer2 *l2, struct sk_buff *skb)
{
	return skb->data[l2addrsize(l2)] & 0x10;
}

inline u_char
get_PollFlagFree(struct layer2 *l2, struct sk_buff *skb)
{
	u_char PF;

	PF = get_PollFlag(l2, skb);
	dev_kfree_skb(skb);
	return PF;
}

inline void
start_t200(struct layer2 *l2, int i)
{
	mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, i);
	test_and_set_bit(FLG_T200_RUN, &l2->flag);
}

inline void
restart_t200(struct layer2 *l2, int i)
{
	mISDN_FsmRestartTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, i);
	test_and_set_bit(FLG_T200_RUN, &l2->flag);
}

inline void
stop_t200(struct layer2 *l2, int i)
{
	if (test_and_clear_bit(FLG_T200_RUN, &l2->flag))
		mISDN_FsmDelTimer(&l2->t200, i);
}

inline void
st5_dl_release_l2l3(struct layer2 *l2)
{
	int pr;

	if (test_and_clear_bit(FLG_PEND_REL, &l2->flag))
		pr = DL_RELEASE_CNF;
	else
		pr = DL_RELEASE_IND;
	l2up_create(l2, pr, 0, NULL);
}

inline void
lapb_dl_release_l2l3(struct layer2 *l2, int f)
{
	if (test_bit(FLG_LAPB, &l2->flag))
		l2down_create(l2, PH_DEACTIVATE_REQ, l2_newid(l2), 0, NULL);
	l2up_create(l2, f, 0, NULL);
}

static void
establishlink(struct FsmInst *fi)
{
	struct layer2 *l2 = fi->userdata;
	u_char cmd;

	clear_exception(l2);
	l2->rc = 0;
	cmd = (test_bit(FLG_MOD128, &l2->flag) ? SABME : SABM) | 0x10;
	send_uframe(l2, NULL, cmd, CMD);
	mISDN_FsmDelTimer(&l2->t203, 1);
	restart_t200(l2, 1);
	test_and_clear_bit(FLG_PEND_REL, &l2->flag);
	freewin(l2);
	mISDN_FsmChangeState(fi, ST_L2_5);
}

static void
l2_mdl_error_ua(struct FsmInst *fi, int event, void *arg)
{
	struct sk_buff *skb = arg;
	struct layer2 *l2 = fi->userdata;

	if (get_PollFlagFree(l2, skb))
		l2mgr(l2, MDL_ERROR_IND, (void *) 'C');
	else
		l2mgr(l2, MDL_ERROR_IND, (void *) 'D');

}

static void
l2_mdl_error_dm(struct FsmInst *fi, int event, void *arg)
{
	struct sk_buff *skb = arg;
	struct layer2 *l2 = fi->userdata;

	if (get_PollFlagFree(l2, skb))
		l2mgr(l2, MDL_ERROR_IND, (void *) 'B');
	else {
		l2mgr(l2, MDL_ERROR_IND, (void *) 'E');
		establishlink(fi);
		test_and_clear_bit(FLG_L3_INIT, &l2->flag);
	}
}

static void
l2_st8_mdl_error_dm(struct FsmInst *fi, int event, void *arg)
{
	struct sk_buff *skb = arg;
	struct layer2 *l2 = fi->userdata;

	if (get_PollFlagFree(l2, skb))
		l2mgr(l2, MDL_ERROR_IND, (void *) 'B');
	else
		l2mgr(l2, MDL_ERROR_IND, (void *) 'E');
	establishlink(fi);
	test_and_clear_bit(FLG_L3_INIT, &l2->flag);
}

static void
l2_go_st3(struct FsmInst *fi, int event, void *arg)
{
	dev_kfree_skb((struct sk_buff *)arg);
	mISDN_FsmChangeState(fi, ST_L2_3);
}

static void
l2_mdl_assign(struct FsmInst *fi, int event, void *arg)
{
	struct layer2	*l2 = fi->userdata;

	mISDN_FsmChangeState(fi, ST_L2_3);
	dev_kfree_skb((struct sk_buff *)arg);
	l2_tei(l2, MDL_ASSIGN_IND, 0);
}

static void
l2_queue_ui_assign(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_queue_tail(&l2->ui_queue, skb);
	mISDN_FsmChangeState(fi, ST_L2_2);
	l2_tei(l2, MDL_ASSIGN_IND, 0);
}

static void
l2_queue_ui(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_queue_tail(&l2->ui_queue, skb);
}

static void
tx_ui(struct layer2 *l2)
{
	struct sk_buff *skb;
	u_char header[MAX_L2HEADER_LEN];
	int i;

	i = sethdraddr(l2, header, CMD);
	if (test_bit(FLG_LAPD_NET, &l2->flag))
		header[1] = 0xff; /* tei 127 */
	header[i++] = UI;
	while ((skb = skb_dequeue(&l2->ui_queue))) {
		memcpy(skb_push(skb, i), header, i);
		enqueue_ui(l2, skb);
	}
}

static void
l2_send_ui(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_queue_tail(&l2->ui_queue, skb);
	tx_ui(l2);
}

static void
l2_got_ui(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_pull(skb, l2headersize(l2, 1));
/*
 *		in states 1-3 for broadcast
 */

	if (l2->tm)
		l2_tei(l2, MDL_STATUS_UI_IND, 0);
	l2up(l2, DL_UNITDATA_IND, skb);
}

static void
l2_establish(struct FsmInst *fi, int event, void *arg)
{
	struct sk_buff *skb = arg;
	struct layer2 *l2 = fi->userdata;

	establishlink(fi);
	test_and_set_bit(FLG_L3_INIT, &l2->flag);
	dev_kfree_skb(skb);
}

static void
l2_discard_i_setl3(struct FsmInst *fi, int event, void *arg)
{
	struct sk_buff *skb = arg;
	struct layer2 *l2 = fi->userdata;

	skb_queue_purge(&l2->i_queue);
	test_and_set_bit(FLG_L3_INIT, &l2->flag);
	test_and_clear_bit(FLG_PEND_REL, &l2->flag);
	dev_kfree_skb(skb);
}

static void
l2_l3_reestablish(struct FsmInst *fi, int event, void *arg)
{
	struct sk_buff *skb = arg;
	struct layer2 *l2 = fi->userdata;

	skb_queue_purge(&l2->i_queue);
	establishlink(fi);
	test_and_set_bit(FLG_L3_INIT, &l2->flag);
	dev_kfree_skb(skb);
}

static void
l2_release(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_trim(skb, 0);
	l2up(l2, DL_RELEASE_CNF, skb);
}

static void
l2_pend_rel(struct FsmInst *fi, int event, void *arg)
{
	struct sk_buff *skb = arg;
	struct layer2 *l2 = fi->userdata;

	test_and_set_bit(FLG_PEND_REL, &l2->flag);
	dev_kfree_skb(skb);
}

static void
l2_disconnect(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_queue_purge(&l2->i_queue);
	freewin(l2);
	mISDN_FsmChangeState(fi, ST_L2_6);
	l2->rc = 0;
	send_uframe(l2, NULL, DISC | 0x10, CMD);
	mISDN_FsmDelTimer(&l2->t203, 1);
	restart_t200(l2, 2);
	if (skb)
		dev_kfree_skb(skb);
}

static void
l2_start_multi(struct FsmInst *fi, int event, void *arg)
{
	struct layer2	*l2 = fi->userdata;
	struct sk_buff	*skb = arg;

	l2->vs = 0;
	l2->va = 0;
	l2->vr = 0;
	l2->sow = 0;
	clear_exception(l2);
	send_uframe(l2, NULL, UA | get_PollFlag(l2, skb), RSP);
	mISDN_FsmChangeState(fi, ST_L2_7);
	mISDN_FsmAddTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 3);
	skb_trim(skb, 0);
	l2up(l2, DL_ESTABLISH_IND, skb);
	if (l2->tm)
		l2_tei(l2, MDL_STATUS_UP_IND, 0);
}

static void
l2_send_UA(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	send_uframe(l2, skb, UA | get_PollFlag(l2, skb), RSP);
}

static void
l2_send_DM(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	send_uframe(l2, skb, DM | get_PollFlag(l2, skb), RSP);
}

static void
l2_restart_multi(struct FsmInst *fi, int event, void *arg)
{
	struct layer2	*l2 = fi->userdata;
	struct sk_buff	*skb = arg;
	int		est = 0;

	send_uframe(l2, skb, UA | get_PollFlag(l2, skb), RSP);

	l2mgr(l2, MDL_ERROR_IND, (void *) 'F');

	if (l2->vs != l2->va) {
		skb_queue_purge(&l2->i_queue);
		est = 1;
	}

	clear_exception(l2);
	l2->vs = 0;
	l2->va = 0;
	l2->vr = 0;
	l2->sow = 0;
	mISDN_FsmChangeState(fi, ST_L2_7);
	stop_t200(l2, 3);
	mISDN_FsmRestartTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 3);

	if (est)
		l2up_create(l2, DL_ESTABLISH_IND, 0, NULL);
/*		mISDN_queue_data(&l2->inst, l2->inst.id | MSG_BROADCAST,
 *		    MGR_SHORTSTATUS | INDICATION, SSTATUS_L2_ESTABLISHED,
 *		    0, NULL, 0);
 */
	if (skb_queue_len(&l2->i_queue) && cansend(l2))
		mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
}

static void
l2_stop_multi(struct FsmInst *fi, int event, void *arg)
{
	struct layer2	*l2 = fi->userdata;
	struct sk_buff	*skb = arg;

	mISDN_FsmChangeState(fi, ST_L2_4);
	mISDN_FsmDelTimer(&l2->t203, 3);
	stop_t200(l2, 4);

	send_uframe(l2, skb, UA | get_PollFlag(l2, skb), RSP);
	skb_queue_purge(&l2->i_queue);
	freewin(l2);
	lapb_dl_release_l2l3(l2, DL_RELEASE_IND);
	if (l2->tm)
		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
}

static void
l2_connected(struct FsmInst *fi, int event, void *arg)
{
	struct layer2	*l2 = fi->userdata;
	struct sk_buff	*skb = arg;
	int pr = -1;

	if (!get_PollFlag(l2, skb)) {
		l2_mdl_error_ua(fi, event, arg);
		return;
	}
	dev_kfree_skb(skb);
	if (test_and_clear_bit(FLG_PEND_REL, &l2->flag))
		l2_disconnect(fi, event, NULL);
	if (test_and_clear_bit(FLG_L3_INIT, &l2->flag)) {
		pr = DL_ESTABLISH_CNF;
	} else if (l2->vs != l2->va) {
		skb_queue_purge(&l2->i_queue);
		pr = DL_ESTABLISH_IND;
	}
	stop_t200(l2, 5);
	l2->vr = 0;
	l2->vs = 0;
	l2->va = 0;
	l2->sow = 0;
	mISDN_FsmChangeState(fi, ST_L2_7);
	mISDN_FsmAddTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 4);
	if (pr != -1)
		l2up_create(l2, pr, 0, NULL);

	if (skb_queue_len(&l2->i_queue) && cansend(l2))
		mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);

	if (l2->tm)
		l2_tei(l2, MDL_STATUS_UP_IND, 0);
}

static void
l2_released(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	if (!get_PollFlag(l2, skb)) {
		l2_mdl_error_ua(fi, event, arg);
		return;
	}
	dev_kfree_skb(skb);
	stop_t200(l2, 6);
	lapb_dl_release_l2l3(l2, DL_RELEASE_CNF);
	mISDN_FsmChangeState(fi, ST_L2_4);
	if (l2->tm)
		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
}

static void
l2_reestablish(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	if (!get_PollFlagFree(l2, skb)) {
		establishlink(fi);
		test_and_set_bit(FLG_L3_INIT, &l2->flag);
	}
}

static void
l2_st5_dm_release(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	if (get_PollFlagFree(l2, skb)) {
		stop_t200(l2, 7);
		if (!test_bit(FLG_L3_INIT, &l2->flag))
			skb_queue_purge(&l2->i_queue);
		if (test_bit(FLG_LAPB, &l2->flag))
			l2down_create(l2, PH_DEACTIVATE_REQ,
				      l2_newid(l2), 0, NULL);
		st5_dl_release_l2l3(l2);
		mISDN_FsmChangeState(fi, ST_L2_4);
		if (l2->tm)
			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
	}
}

static void
l2_st6_dm_release(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	if (get_PollFlagFree(l2, skb)) {
		stop_t200(l2, 8);
		lapb_dl_release_l2l3(l2, DL_RELEASE_CNF);
		mISDN_FsmChangeState(fi, ST_L2_4);
		if (l2->tm)
			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
	}
}

static void
enquiry_cr(struct layer2 *l2, u_char typ, u_char cr, u_char pf)
{
	struct sk_buff *skb;
	u_char tmp[MAX_L2HEADER_LEN];
	int i;

	i = sethdraddr(l2, tmp, cr);
	if (test_bit(FLG_MOD128, &l2->flag)) {
		tmp[i++] = typ;
		tmp[i++] = (l2->vr << 1) | (pf ? 1 : 0);
	} else
		tmp[i++] = (l2->vr << 5) | typ | (pf ? 0x10 : 0);
	skb = mI_alloc_skb(i, GFP_ATOMIC);
	if (!skb) {
		printk(KERN_WARNING "%s: isdnl2 can't alloc sbbuff in %s\n",
		       mISDNDevName4ch(&l2->ch), __func__);
		return;
	}
	skb_put_data(skb, tmp, i);
	enqueue_super(l2, skb);
}

inline void
enquiry_response(struct layer2 *l2)
{
	if (test_bit(FLG_OWN_BUSY, &l2->flag))
		enquiry_cr(l2, RNR, RSP, 1);
	else
		enquiry_cr(l2, RR, RSP, 1);
	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
}

inline void
transmit_enquiry(struct layer2 *l2)
{
	if (test_bit(FLG_OWN_BUSY, &l2->flag))
		enquiry_cr(l2, RNR, CMD, 1);
	else
		enquiry_cr(l2, RR, CMD, 1);
	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
	start_t200(l2, 9);
}


static void
nrerrorrecovery(struct FsmInst *fi)
{
	struct layer2 *l2 = fi->userdata;

	l2mgr(l2, MDL_ERROR_IND, (void *) 'J');
	establishlink(fi);
	test_and_clear_bit(FLG_L3_INIT, &l2->flag);
}

static void
invoke_retransmission(struct layer2 *l2, unsigned int nr)
{
	u_int	p1;

	if (l2->vs != nr) {
		while (l2->vs != nr) {
			(l2->vs)--;
			if (test_bit(FLG_MOD128, &l2->flag)) {
				l2->vs %= 128;
				p1 = (l2->vs - l2->va) % 128;
			} else {
				l2->vs %= 8;
				p1 = (l2->vs - l2->va) % 8;
			}
			p1 = (p1 + l2->sow) % l2->window;
			if (l2->windowar[p1])
				skb_queue_head(&l2->i_queue, l2->windowar[p1]);
			else
				printk(KERN_WARNING
				       "%s: windowar[%d] is NULL\n",
				       mISDNDevName4ch(&l2->ch), p1);
			l2->windowar[p1] = NULL;
		}
		mISDN_FsmEvent(&l2->l2m, EV_L2_ACK_PULL, NULL);
	}
}

static void
l2_st7_got_super(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;
	int PollFlag, rsp, typ = RR;
	unsigned int nr;

	rsp = *skb->data & 0x2;
	if (test_bit(FLG_ORIG, &l2->flag))
		rsp = !rsp;

	skb_pull(skb, l2addrsize(l2));
	if (IsRNR(skb->data, l2)) {
		set_peer_busy(l2);
		typ = RNR;
	} else
		clear_peer_busy(l2);
	if (IsREJ(skb->data, l2))
		typ = REJ;

	if (test_bit(FLG_MOD128, &l2->flag)) {
		PollFlag = (skb->data[1] & 0x1) == 0x1;
		nr = skb->data[1] >> 1;
	} else {
		PollFlag = (skb->data[0] & 0x10);
		nr = (skb->data[0] >> 5) & 0x7;
	}
	dev_kfree_skb(skb);

	if (PollFlag) {
		if (rsp)
			l2mgr(l2, MDL_ERROR_IND, (void *) 'A');
		else
			enquiry_response(l2);
	}
	if (legalnr(l2, nr)) {
		if (typ == REJ) {
			setva(l2, nr);
			invoke_retransmission(l2, nr);
			stop_t200(l2, 10);
			if (mISDN_FsmAddTimer(&l2->t203, l2->T203,
					      EV_L2_T203, NULL, 6))
				l2m_debug(&l2->l2m, "Restart T203 ST7 REJ");
		} else if ((nr == l2->vs) && (typ == RR)) {
			setva(l2, nr);
			stop_t200(l2, 11);
			mISDN_FsmRestartTimer(&l2->t203, l2->T203,
					      EV_L2_T203, NULL, 7);
		} else if ((l2->va != nr) || (typ == RNR)) {
			setva(l2, nr);
			if (typ != RR)
				mISDN_FsmDelTimer(&l2->t203, 9);
			restart_t200(l2, 12);
		}
		if (skb_queue_len(&l2->i_queue) && (typ == RR))
			mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
	} else
		nrerrorrecovery(fi);
}

static void
l2_feed_i_if_reest(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	if (!test_bit(FLG_L3_INIT, &l2->flag))
		skb_queue_tail(&l2->i_queue, skb);
	else
		dev_kfree_skb(skb);
}

static void
l2_feed_i_pull(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_queue_tail(&l2->i_queue, skb);
	mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
}

static void
l2_feed_iqueue(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_queue_tail(&l2->i_queue, skb);
}

static void
l2_got_iframe(struct FsmInst *fi, int event, void *arg)
{
	struct layer2	*l2 = fi->userdata;
	struct sk_buff	*skb = arg;
	int		PollFlag, i;
	u_int		ns, nr;

	i = l2addrsize(l2);
	if (test_bit(FLG_MOD128, &l2->flag)) {
		PollFlag = ((skb->data[i + 1] & 0x1) == 0x1);
		ns = skb->data[i] >> 1;
		nr = (skb->data[i + 1] >> 1) & 0x7f;
	} else {
		PollFlag = (skb->data[i] & 0x10);
		ns = (skb->data[i] >> 1) & 0x7;
		nr = (skb->data[i] >> 5) & 0x7;
	}
	if (test_bit(FLG_OWN_BUSY, &l2->flag)) {
		dev_kfree_skb(skb);
		if (PollFlag)
			enquiry_response(l2);
	} else {
		if (l2->vr == ns) {
			l2->vr++;
			if (test_bit(FLG_MOD128, &l2->flag))
				l2->vr %= 128;
			else
				l2->vr %= 8;
			test_and_clear_bit(FLG_REJEXC, &l2->flag);
			if (PollFlag)
				enquiry_response(l2);
			else
				test_and_set_bit(FLG_ACK_PEND, &l2->flag);
			skb_pull(skb, l2headersize(l2, 0));
			l2up(l2, DL_DATA_IND, skb);
		} else {
			/* n(s)!=v(r) */
			dev_kfree_skb(skb);
			if (test_and_set_bit(FLG_REJEXC, &l2->flag)) {
				if (PollFlag)
					enquiry_response(l2);
			} else {
				enquiry_cr(l2, REJ, RSP, PollFlag);
				test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
			}
		}
	}
	if (legalnr(l2, nr)) {
		if (!test_bit(FLG_PEER_BUSY, &l2->flag) &&
		    (fi->state == ST_L2_7)) {
			if (nr == l2->vs) {
				stop_t200(l2, 13);
				mISDN_FsmRestartTimer(&l2->t203, l2->T203,
						      EV_L2_T203, NULL, 7);
			} else if (nr != l2->va)
				restart_t200(l2, 14);
		}
		setva(l2, nr);
	} else {
		nrerrorrecovery(fi);
		return;
	}
	if (skb_queue_len(&l2->i_queue) && (fi->state == ST_L2_7))
		mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
	if (test_and_clear_bit(FLG_ACK_PEND, &l2->flag))
		enquiry_cr(l2, RR, RSP, 0);
}

static void
l2_got_tei(struct FsmInst *fi, int event, void *arg)
{
	struct layer2	*l2 = fi->userdata;
	u_int		info;

	l2->tei = (signed char)(long)arg;
	set_channel_address(&l2->ch, l2->sapi, l2->tei);
	info = DL_INFO_L2_CONNECT;
	l2up_create(l2, DL_INFORMATION_IND, sizeof(info), &info);
	if (fi->state == ST_L2_3) {
		establishlink(fi);
		test_and_set_bit(FLG_L3_INIT, &l2->flag);
	} else
		mISDN_FsmChangeState(fi, ST_L2_4);
	if (skb_queue_len(&l2->ui_queue))
		tx_ui(l2);
}

static void
l2_st5_tout_200(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	if (test_bit(FLG_LAPD, &l2->flag) &&
	    test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
	} else if (l2->rc == l2->N200) {
		mISDN_FsmChangeState(fi, ST_L2_4);
		test_and_clear_bit(FLG_T200_RUN, &l2->flag);
		skb_queue_purge(&l2->i_queue);
		l2mgr(l2, MDL_ERROR_IND, (void *) 'G');
		if (test_bit(FLG_LAPB, &l2->flag))
			l2down_create(l2, PH_DEACTIVATE_REQ,
				      l2_newid(l2), 0, NULL);
		st5_dl_release_l2l3(l2);
		if (l2->tm)
			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
	} else {
		l2->rc++;
		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
		send_uframe(l2, NULL, (test_bit(FLG_MOD128, &l2->flag) ?
				       SABME : SABM) | 0x10, CMD);
	}
}

static void
l2_st6_tout_200(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	if (test_bit(FLG_LAPD, &l2->flag) &&
	    test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
	} else if (l2->rc == l2->N200) {
		mISDN_FsmChangeState(fi, ST_L2_4);
		test_and_clear_bit(FLG_T200_RUN, &l2->flag);
		l2mgr(l2, MDL_ERROR_IND, (void *) 'H');
		lapb_dl_release_l2l3(l2, DL_RELEASE_CNF);
		if (l2->tm)
			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
	} else {
		l2->rc++;
		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200,
				  NULL, 9);
		send_uframe(l2, NULL, DISC | 0x10, CMD);
	}
}

static void
l2_st7_tout_200(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	if (test_bit(FLG_LAPD, &l2->flag) &&
	    test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
		return;
	}
	test_and_clear_bit(FLG_T200_RUN, &l2->flag);
	l2->rc = 0;
	mISDN_FsmChangeState(fi, ST_L2_8);
	transmit_enquiry(l2);
	l2->rc++;
}

static void
l2_st8_tout_200(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	if (test_bit(FLG_LAPD, &l2->flag) &&
	    test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
		return;
	}
	test_and_clear_bit(FLG_T200_RUN, &l2->flag);
	if (l2->rc == l2->N200) {
		l2mgr(l2, MDL_ERROR_IND, (void *) 'I');
		establishlink(fi);
		test_and_clear_bit(FLG_L3_INIT, &l2->flag);
	} else {
		transmit_enquiry(l2);
		l2->rc++;
	}
}

static void
l2_st7_tout_203(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	if (test_bit(FLG_LAPD, &l2->flag) &&
	    test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
		mISDN_FsmAddTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 9);
		return;
	}
	mISDN_FsmChangeState(fi, ST_L2_8);
	transmit_enquiry(l2);
	l2->rc = 0;
}

static void
l2_pull_iqueue(struct FsmInst *fi, int event, void *arg)
{
	struct layer2	*l2 = fi->userdata;
	struct sk_buff	*skb, *nskb;
	u_char		header[MAX_L2HEADER_LEN];
	u_int		i, p1;

	if (!cansend(l2))
		return;

	skb = skb_dequeue(&l2->i_queue);
	if (!skb)
		return;
	i = sethdraddr(l2, header, CMD);
	if (test_bit(FLG_MOD128, &l2->flag)) {
		header[i++] = l2->vs << 1;
		header[i++] = l2->vr << 1;
	} else
		header[i++] = (l2->vr << 5) | (l2->vs << 1);
	nskb = skb_realloc_headroom(skb, i);
	if (!nskb) {
		printk(KERN_WARNING "%s: no headroom(%d) copy for IFrame\n",
		       mISDNDevName4ch(&l2->ch), i);
		skb_queue_head(&l2->i_queue, skb);
		return;
	}
	if (test_bit(FLG_MOD128, &l2->flag)) {
		p1 = (l2->vs - l2->va) % 128;
		l2->vs = (l2->vs + 1) % 128;
	} else {
		p1 = (l2->vs - l2->va) % 8;
		l2->vs = (l2->vs + 1) % 8;
	}
	p1 = (p1 + l2->sow) % l2->window;
	if (l2->windowar[p1]) {
		printk(KERN_WARNING "%s: l2 try overwrite ack queue entry %d\n",
		       mISDNDevName4ch(&l2->ch), p1);
		dev_kfree_skb(l2->windowar[p1]);
	}
	l2->windowar[p1] = skb;
	memcpy(skb_push(nskb, i), header, i);
	l2down(l2, PH_DATA_REQ, l2_newid(l2), nskb);
	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
	if (!test_and_set_bit(FLG_T200_RUN, &l2->flag)) {
		mISDN_FsmDelTimer(&l2->t203, 13);
		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 11);
	}
}

static void
l2_st8_got_super(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;
	int PollFlag, rsp, rnr = 0;
	unsigned int nr;

	rsp = *skb->data & 0x2;
	if (test_bit(FLG_ORIG, &l2->flag))
		rsp = !rsp;

	skb_pull(skb, l2addrsize(l2));

	if (IsRNR(skb->data, l2)) {
		set_peer_busy(l2);
		rnr = 1;
	} else
		clear_peer_busy(l2);

	if (test_bit(FLG_MOD128, &l2->flag)) {
		PollFlag = (skb->data[1] & 0x1) == 0x1;
		nr = skb->data[1] >> 1;
	} else {
		PollFlag = (skb->data[0] & 0x10);
		nr = (skb->data[0] >> 5) & 0x7;
	}
	dev_kfree_skb(skb);
	if (rsp && PollFlag) {
		if (legalnr(l2, nr)) {
			if (rnr) {
				restart_t200(l2, 15);
			} else {
				stop_t200(l2, 16);
				mISDN_FsmAddTimer(&l2->t203, l2->T203,
						  EV_L2_T203, NULL, 5);
				setva(l2, nr);
			}
			invoke_retransmission(l2, nr);
			mISDN_FsmChangeState(fi, ST_L2_7);
			if (skb_queue_len(&l2->i_queue) && cansend(l2))
				mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
		} else
			nrerrorrecovery(fi);
	} else {
		if (!rsp && PollFlag)
			enquiry_response(l2);
		if (legalnr(l2, nr))
			setva(l2, nr);
		else
			nrerrorrecovery(fi);
	}
}

static void
l2_got_FRMR(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_pull(skb, l2addrsize(l2) + 1);

	if (!(skb->data[0] & 1) || ((skb->data[0] & 3) == 1) || /* I or S */
	    (IsUA(skb->data) && (fi->state == ST_L2_7))) {
		l2mgr(l2, MDL_ERROR_IND, (void *) 'K');
		establishlink(fi);
		test_and_clear_bit(FLG_L3_INIT, &l2->flag);
	}
	dev_kfree_skb(skb);
}

static void
l2_st24_tei_remove(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	skb_queue_purge(&l2->ui_queue);
	l2->tei = GROUP_TEI;
	mISDN_FsmChangeState(fi, ST_L2_1);
}

static void
l2_st3_tei_remove(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	skb_queue_purge(&l2->ui_queue);
	l2->tei = GROUP_TEI;
	l2up_create(l2, DL_RELEASE_IND, 0, NULL);
	mISDN_FsmChangeState(fi, ST_L2_1);
}

static void
l2_st5_tei_remove(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	skb_queue_purge(&l2->i_queue);
	skb_queue_purge(&l2->ui_queue);
	freewin(l2);
	l2->tei = GROUP_TEI;
	stop_t200(l2, 17);
	st5_dl_release_l2l3(l2);
	mISDN_FsmChangeState(fi, ST_L2_1);
}

static void
l2_st6_tei_remove(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	skb_queue_purge(&l2->ui_queue);
	l2->tei = GROUP_TEI;
	stop_t200(l2, 18);
	l2up_create(l2, DL_RELEASE_IND, 0, NULL);
	mISDN_FsmChangeState(fi, ST_L2_1);
}

static void
l2_tei_remove(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	skb_queue_purge(&l2->i_queue);
	skb_queue_purge(&l2->ui_queue);
	freewin(l2);
	l2->tei = GROUP_TEI;
	stop_t200(l2, 17);
	mISDN_FsmDelTimer(&l2->t203, 19);
	l2up_create(l2, DL_RELEASE_IND, 0, NULL);
/*	mISDN_queue_data(&l2->inst, l2->inst.id | MSG_BROADCAST,
 *		MGR_SHORTSTATUS_IND, SSTATUS_L2_RELEASED,
 *		0, NULL, 0);
 */
	mISDN_FsmChangeState(fi, ST_L2_1);
}

static void
l2_st14_persistent_da(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_queue_purge(&l2->i_queue);
	skb_queue_purge(&l2->ui_queue);
	if (test_and_clear_bit(FLG_ESTAB_PEND, &l2->flag))
		l2up(l2, DL_RELEASE_IND, skb);
	else
		dev_kfree_skb(skb);
}

static void
l2_st5_persistent_da(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_queue_purge(&l2->i_queue);
	skb_queue_purge(&l2->ui_queue);
	freewin(l2);
	stop_t200(l2, 19);
	st5_dl_release_l2l3(l2);
	mISDN_FsmChangeState(fi, ST_L2_4);
	if (l2->tm)
		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
	dev_kfree_skb(skb);
}

static void
l2_st6_persistent_da(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_queue_purge(&l2->ui_queue);
	stop_t200(l2, 20);
	l2up(l2, DL_RELEASE_CNF, skb);
	mISDN_FsmChangeState(fi, ST_L2_4);
	if (l2->tm)
		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
}

static void
l2_persistent_da(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	skb_queue_purge(&l2->i_queue);
	skb_queue_purge(&l2->ui_queue);
	freewin(l2);
	stop_t200(l2, 19);
	mISDN_FsmDelTimer(&l2->t203, 19);
	l2up(l2, DL_RELEASE_IND, skb);
	mISDN_FsmChangeState(fi, ST_L2_4);
	if (l2->tm)
		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
}

static void
l2_set_own_busy(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	if (!test_and_set_bit(FLG_OWN_BUSY, &l2->flag)) {
		enquiry_cr(l2, RNR, RSP, 0);
		test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
	}
	if (skb)
		dev_kfree_skb(skb);
}

static void
l2_clear_own_busy(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;
	struct sk_buff *skb = arg;

	if (!test_and_clear_bit(FLG_OWN_BUSY, &l2->flag)) {
		enquiry_cr(l2, RR, RSP, 0);
		test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
	}
	if (skb)
		dev_kfree_skb(skb);
}

static void
l2_frame_error(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	l2mgr(l2, MDL_ERROR_IND, arg);
}

static void
l2_frame_error_reest(struct FsmInst *fi, int event, void *arg)
{
	struct layer2 *l2 = fi->userdata;

	l2mgr(l2, MDL_ERROR_IND, arg);
	establishlink(fi);
	test_and_clear_bit(FLG_L3_INIT, &l2->flag);
}

static struct FsmNode L2FnList[] =
{
	{ST_L2_1, EV_L2_DL_ESTABLISH_REQ, l2_mdl_assign},
	{ST_L2_2, EV_L2_DL_ESTABLISH_REQ, l2_go_st3},
	{ST_L2_4, EV_L2_DL_ESTABLISH_REQ, l2_establish},
	{ST_L2_5, EV_L2_DL_ESTABLISH_REQ, l2_discard_i_setl3},
	{ST_L2_7, EV_L2_DL_ESTABLISH_REQ, l2_l3_reestablish},
	{ST_L2_8, EV_L2_DL_ESTABLISH_REQ, l2_l3_reestablish},
	{ST_L2_4, EV_L2_DL_RELEASE_REQ, l2_release},
	{ST_L2_5, EV_L2_DL_RELEASE_REQ, l2_pend_rel},
	{ST_L2_7, EV_L2_DL_RELEASE_REQ, l2_disconnect},
	{ST_L2_8, EV_L2_DL_RELEASE_REQ, l2_disconnect},
	{ST_L2_5, EV_L2_DL_DATA, l2_feed_i_if_reest},
	{ST_L2_7, EV_L2_DL_DATA, l2_feed_i_pull},
	{ST_L2_8, EV_L2_DL_DATA, l2_feed_iqueue},
	{ST_L2_1, EV_L2_DL_UNITDATA, l2_queue_ui_assign},
	{ST_L2_2, EV_L2_DL_UNITDATA, l2_queue_ui},
	{ST_L2_3, EV_L2_DL_UNITDATA, l2_queue_ui},
	{ST_L2_4, EV_L2_DL_UNITDATA, l2_send_ui},
	{ST_L2_5, EV_L2_DL_UNITDATA, l2_send_ui},
	{ST_L2_6, EV_L2_DL_UNITDATA, l2_send_ui},
	{ST_L2_7, EV_L2_DL_UNITDATA, l2_send_ui},
	{ST_L2_8, EV_L2_DL_UNITDATA, l2_send_ui},
	{ST_L2_1, EV_L2_MDL_ASSIGN, l2_got_tei},
	{ST_L2_2, EV_L2_MDL_ASSIGN, l2_got_tei},
	{ST_L2_3, EV_L2_MDL_ASSIGN, l2_got_tei},
	{ST_L2_2, EV_L2_MDL_ERROR, l2_st24_tei_remove},
	{ST_L2_3, EV_L2_MDL_ERROR, l2_st3_tei_remove},
	{ST_L2_4, EV_L2_MDL_REMOVE, l2_st24_tei_remove},
	{ST_L2_5, EV_L2_MDL_REMOVE, l2_st5_tei_remove},
	{ST_L2_6, EV_L2_MDL_REMOVE, l2_st6_tei_remove},
	{ST_L2_7, EV_L2_MDL_REMOVE, l2_tei_remove},
	{ST_L2_8, EV_L2_MDL_REMOVE, l2_tei_remove},
	{ST_L2_4, EV_L2_SABME, l2_start_multi},
	{ST_L2_5, EV_L2_SABME, l2_send_UA},
	{ST_L2_6, EV_L2_SABME, l2_send_DM},
	{ST_L2_7, EV_L2_SABME, l2_restart_multi},
	{ST_L2_8, EV_L2_SABME, l2_restart_multi},
	{ST_L2_4, EV_L2_DISC, l2_send_DM},
	{ST_L2_5, EV_L2_DISC, l2_send_DM},
	{ST_L2_6, EV_L2_DISC, l2_send_UA},
	{ST_L2_7, EV_L2_DISC, l2_stop_multi},
	{ST_L2_8, EV_L2_DISC, l2_stop_multi},
	{ST_L2_4, EV_L2_UA, l2_mdl_error_ua},
	{ST_L2_5, EV_L2_UA, l2_connected},
	{ST_L2_6, EV_L2_UA, l2_released},
	{ST_L2_7, EV_L2_UA, l2_mdl_error_ua},
	{ST_L2_8, EV_L2_UA, l2_mdl_error_ua},
	{ST_L2_4, EV_L2_DM, l2_reestablish},
	{ST_L2_5, EV_L2_DM, l2_st5_dm_release},
	{ST_L2_6, EV_L2_DM, l2_st6_dm_release},
	{ST_L2_7, EV_L2_DM, l2_mdl_error_dm},
	{ST_L2_8, EV_L2_DM, l2_st8_mdl_error_dm},
	{ST_L2_1, EV_L2_UI, l2_got_ui},
	{ST_L2_2, EV_L2_UI, l2_got_ui},
	{ST_L2_3, EV_L2_UI, l2_got_ui},
	{ST_L2_4, EV_L2_UI, l2_got_ui},
	{ST_L2_5, EV_L2_UI, l2_got_ui},
	{ST_L2_6, EV_L2_UI, l2_got_ui},
	{ST_L2_7, EV_L2_UI, l2_got_ui},
	{ST_L2_8, EV_L2_UI, l2_got_ui},
	{ST_L2_7, EV_L2_FRMR, l2_got_FRMR},
	{ST_L2_8, EV_L2_FRMR, l2_got_FRMR},
	{ST_L2_7, EV_L2_SUPER, l2_st7_got_super},
	{ST_L2_8, EV_L2_SUPER, l2_st8_got_super},
	{ST_L2_7, EV_L2_I, l2_got_iframe},
	{ST_L2_8, EV_L2_I, l2_got_iframe},
	{ST_L2_5, EV_L2_T200, l2_timeout},
	{ST_L2_6, EV_L2_T200, l2_timeout},
	{ST_L2_7, EV_L2_T200, l2_timeout},
	{ST_L2_8, EV_L2_T200, l2_timeout},
	{ST_L2_7, EV_L2_T203, l2_timeout},
	{ST_L2_5, EV_L2_T200I, l2_st5_tout_200},
	{ST_L2_6, EV_L2_T200I, l2_st6_tout_200},
	{ST_L2_7, EV_L2_T200I, l2_st7_tout_200},
	{ST_L2_8, EV_L2_T200I, l2_st8_tout_200},
	{ST_L2_7, EV_L2_T203I, l2_st7_tout_203},
	{ST_L2_7, EV_L2_ACK_PULL, l2_pull_iqueue},
	{ST_L2_7, EV_L2_SET_OWN_BUSY, l2_set_own_busy},
	{ST_L2_8, EV_L2_SET_OWN_BUSY, l2_set_own_busy},
	{ST_L2_7, EV_L2_CLEAR_OWN_BUSY, l2_clear_own_busy},
	{ST_L2_8, EV_L2_CLEAR_OWN_BUSY, l2_clear_own_busy},
	{ST_L2_4, EV_L2_FRAME_ERROR, l2_frame_error},
	{ST_L2_5, EV_L2_FRAME_ERROR, l2_frame_error},
	{ST_L2_6, EV_L2_FRAME_ERROR, l2_frame_error},
	{ST_L2_7, EV_L2_FRAME_ERROR, l2_frame_error_reest},
	{ST_L2_8, EV_L2_FRAME_ERROR, l2_frame_error_reest},
	{ST_L2_1, EV_L1_DEACTIVATE, l2_st14_persistent_da},
	{ST_L2_2, EV_L1_DEACTIVATE, l2_st24_tei_remove},
	{ST_L2_3, EV_L1_DEACTIVATE, l2_st3_tei_remove},
	{ST_L2_4, EV_L1_DEACTIVATE, l2_st14_persistent_da},
	{ST_L2_5, EV_L1_DEACTIVATE, l2_st5_persistent_da},
	{ST_L2_6, EV_L1_DEACTIVATE, l2_st6_persistent_da},
	{ST_L2_7, EV_L1_DEACTIVATE, l2_persistent_da},
	{ST_L2_8, EV_L1_DEACTIVATE, l2_persistent_da},
};

static int
ph_data_indication(struct layer2 *l2, struct mISDNhead *hh, struct sk_buff *skb)
{
	u_char	*datap = skb->data;
	int	ret = -EINVAL;
	int	psapi, ptei;
	u_int	l;
	int	c = 0;

	l = l2addrsize(l2);
	if (skb->len <= l) {
		mISDN_FsmEvent(&l2->l2m, EV_L2_FRAME_ERROR, (void *) 'N');
		return ret;
	}
	if (test_bit(FLG_LAPD, &l2->flag)) { /* Maybe not needed */
		psapi = *datap++;
		ptei = *datap++;
		if ((psapi & 1) || !(ptei & 1)) {
			printk(KERN_WARNING
			       "%s l2 D-channel frame wrong EA0/EA1\n",
			       mISDNDevName4ch(&l2->ch));
			return ret;
		}
		psapi >>= 2;
		ptei >>= 1;
		if (psapi != l2->sapi) {
			/* not our business */
			if (*debug & DEBUG_L2)
				printk(KERN_DEBUG "%s: sapi %d/%d mismatch\n",
				       mISDNDevName4ch(&l2->ch), psapi,
				       l2->sapi);
			dev_kfree_skb(skb);
			return 0;
		}
		if ((ptei != l2->tei) && (ptei != GROUP_TEI)) {
			/* not our business */
			if (*debug & DEBUG_L2)
				printk(KERN_DEBUG "%s: tei %d/%d mismatch\n",
				       mISDNDevName4ch(&l2->ch), ptei, l2->tei);
			dev_kfree_skb(skb);
			return 0;
		}
	} else
		datap += l;
	if (!(*datap & 1)) {	/* I-Frame */
		c = iframe_error(l2, skb);
		if (!c)
			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_I, skb);
	} else if (IsSFrame(datap, l2)) {	/* S-Frame */
		c = super_error(l2, skb);
		if (!c)
			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_SUPER, skb);
	} else if (IsUI(datap)) {
		c = UI_error(l2, skb);
		if (!c)
			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_UI, skb);
	} else if (IsSABME(datap, l2)) {
		c = unnum_error(l2, skb, CMD);
		if (!c)
			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_SABME, skb);
	} else if (IsUA(datap)) {
		c = unnum_error(l2, skb, RSP);
		if (!c)
			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_UA, skb);
	} else if (IsDISC(datap)) {
		c = unnum_error(l2, skb, CMD);
		if (!c)
			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DISC, skb);
	} else if (IsDM(datap)) {
		c = unnum_error(l2, skb, RSP);
		if (!c)
			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DM, skb);
	} else if (IsFRMR(datap)) {
		c = FRMR_error(l2, skb);
		if (!c)
			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_FRMR, skb);
	} else
		c = 'L';
	if (c) {
		printk(KERN_WARNING "%s:l2 D-channel frame error %c\n",
		       mISDNDevName4ch(&l2->ch), c);
		mISDN_FsmEvent(&l2->l2m, EV_L2_FRAME_ERROR, (void *)(long)c);
	}
	return ret;
}

static int
l2_send(struct mISDNchannel *ch, struct sk_buff *skb)
{
	struct layer2		*l2 = container_of(ch, struct layer2, ch);
	struct mISDNhead	*hh =  mISDN_HEAD_P(skb);
	int			ret = -EINVAL;

	if (*debug & DEBUG_L2_RECV)
		printk(KERN_DEBUG "%s: %s prim(%x) id(%x) sapi(%d) tei(%d)\n",
		       __func__, mISDNDevName4ch(&l2->ch), hh->prim, hh->id,
		       l2->sapi, l2->tei);
	if (hh->prim == DL_INTERN_MSG) {
		struct mISDNhead *chh = hh + 1; /* saved copy */

		*hh = *chh;
		if (*debug & DEBUG_L2_RECV)
			printk(KERN_DEBUG "%s: prim(%x) id(%x) internal msg\n",
				mISDNDevName4ch(&l2->ch), hh->prim, hh->id);
	}
	switch (hh->prim) {
	case PH_DATA_IND:
		ret = ph_data_indication(l2, hh, skb);
		break;
	case PH_DATA_CNF:
		ret = ph_data_confirm(l2, hh, skb);
		break;
	case PH_ACTIVATE_IND:
		test_and_set_bit(FLG_L1_ACTIV, &l2->flag);
		l2up_create(l2, MPH_ACTIVATE_IND, 0, NULL);
		if (test_and_clear_bit(FLG_ESTAB_PEND, &l2->flag))
			ret = mISDN_FsmEvent(&l2->l2m,
					     EV_L2_DL_ESTABLISH_REQ, skb);
		break;
	case PH_DEACTIVATE_IND:
		test_and_clear_bit(FLG_L1_ACTIV, &l2->flag);
		l2up_create(l2, MPH_DEACTIVATE_IND, 0, NULL);
		ret = mISDN_FsmEvent(&l2->l2m, EV_L1_DEACTIVATE, skb);
		break;
	case MPH_INFORMATION_IND:
		if (!l2->up)
			break;
		ret = l2->up->send(l2->up, skb);
		break;
	case DL_DATA_REQ:
		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DL_DATA, skb);
		break;
	case DL_UNITDATA_REQ:
		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DL_UNITDATA, skb);
		break;
	case DL_ESTABLISH_REQ:
		if (test_bit(FLG_LAPB, &l2->flag))
			test_and_set_bit(FLG_ORIG, &l2->flag);
		if (test_bit(FLG_L1_ACTIV, &l2->flag)) {
			if (test_bit(FLG_LAPD, &l2->flag) ||
			    test_bit(FLG_ORIG, &l2->flag))
				ret = mISDN_FsmEvent(&l2->l2m,
						     EV_L2_DL_ESTABLISH_REQ, skb);
		} else {
			if (test_bit(FLG_LAPD, &l2->flag) ||
			    test_bit(FLG_ORIG, &l2->flag)) {
				test_and_set_bit(FLG_ESTAB_PEND,
						 &l2->flag);
			}
			ret = l2down(l2, PH_ACTIVATE_REQ, l2_newid(l2),
				     skb);
		}
		break;
	case DL_RELEASE_REQ:
		if (test_bit(FLG_LAPB, &l2->flag))
			l2down_create(l2, PH_DEACTIVATE_REQ,
				      l2_newid(l2), 0, NULL);
		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DL_RELEASE_REQ,
				     skb);
		break;
	case DL_TIMER200_IND:
		mISDN_FsmEvent(&l2->l2m, EV_L2_T200I, NULL);
		break;
	case DL_TIMER203_IND:
		mISDN_FsmEvent(&l2->l2m, EV_L2_T203I, NULL);
		break;
	default:
		if (*debug & DEBUG_L2)
			l2m_debug(&l2->l2m, "l2 unknown pr %04x",
				  hh->prim);
	}
	if (ret) {
		dev_kfree_skb(skb);
		ret = 0;
	}
	return ret;
}

int
tei_l2(struct layer2 *l2, u_int cmd, u_long arg)
{
	int		ret = -EINVAL;

	if (*debug & DEBUG_L2_TEI)
		printk(KERN_DEBUG "%s: cmd(%x) in %s\n",
		       mISDNDevName4ch(&l2->ch), cmd, __func__);
	switch (cmd) {
	case (MDL_ASSIGN_REQ):
		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_ASSIGN, (void *)arg);
		break;
	case (MDL_REMOVE_REQ):
		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_REMOVE, NULL);
		break;
	case (MDL_ERROR_IND):
		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_ERROR, NULL);
		break;
	case (MDL_ERROR_RSP):
		/* ETS 300-125 5.3.2.1 Test: TC13010 */
		printk(KERN_NOTICE "%s: MDL_ERROR|REQ (tei_l2)\n",
		       mISDNDevName4ch(&l2->ch));
		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_ERROR, NULL);
		break;
	}
	return ret;
}

static void
release_l2(struct layer2 *l2)
{
	mISDN_FsmDelTimer(&l2->t200, 21);
	mISDN_FsmDelTimer(&l2->t203, 16);
	skb_queue_purge(&l2->i_queue);
	skb_queue_purge(&l2->ui_queue);
	skb_queue_purge(&l2->down_queue);
	ReleaseWin(l2);
	if (test_bit(FLG_LAPD, &l2->flag)) {
		TEIrelease(l2);
		if (l2->ch.st)
			l2->ch.st->dev->D.ctrl(&l2->ch.st->dev->D,
					       CLOSE_CHANNEL, NULL);
	}
	kfree(l2);
}

static int
l2_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
{
	struct layer2		*l2 = container_of(ch, struct layer2, ch);
	u_int			info;

	if (*debug & DEBUG_L2_CTRL)
		printk(KERN_DEBUG "%s: %s cmd(%x)\n",
		       mISDNDevName4ch(ch), __func__, cmd);

	switch (cmd) {
	case OPEN_CHANNEL:
		if (test_bit(FLG_LAPD, &l2->flag)) {
			set_channel_address(&l2->ch, l2->sapi, l2->tei);
			info = DL_INFO_L2_CONNECT;
			l2up_create(l2, DL_INFORMATION_IND,
				    sizeof(info), &info);
		}
		break;
	case CLOSE_CHANNEL:
		if (l2->ch.peer)
			l2->ch.peer->ctrl(l2->ch.peer, CLOSE_CHANNEL, NULL);
		release_l2(l2);
		break;
	}
	return 0;
}

struct layer2 *
create_l2(struct mISDNchannel *ch, u_int protocol, u_long options, int tei,
	  int sapi)
{
	struct layer2		*l2;
	struct channel_req	rq;

	l2 = kzalloc(sizeof(struct layer2), GFP_KERNEL);
	if (!l2) {
		printk(KERN_ERR "kzalloc layer2 failed\n");
		return NULL;
	}
	l2->next_id = 1;
	l2->down_id = MISDN_ID_NONE;
	l2->up = ch;
	l2->ch.st = ch->st;
	l2->ch.send = l2_send;
	l2->ch.ctrl = l2_ctrl;
	switch (protocol) {
	case ISDN_P_LAPD_NT:
		test_and_set_bit(FLG_LAPD, &l2->flag);
		test_and_set_bit(FLG_LAPD_NET, &l2->flag);
		test_and_set_bit(FLG_MOD128, &l2->flag);
		l2->sapi = sapi;
		l2->maxlen = MAX_DFRAME_LEN;
		if (test_bit(OPTION_L2_PMX, &options))
			l2->window = 7;
		else
			l2->window = 1;
		if (test_bit(OPTION_L2_PTP, &options))
			test_and_set_bit(FLG_PTP, &l2->flag);
		if (test_bit(OPTION_L2_FIXEDTEI, &options))
			test_and_set_bit(FLG_FIXED_TEI, &l2->flag);
		l2->tei = tei;
		l2->T200 = 1000;
		l2->N200 = 3;
		l2->T203 = 10000;
		if (test_bit(OPTION_L2_PMX, &options))
			rq.protocol = ISDN_P_NT_E1;
		else
			rq.protocol = ISDN_P_NT_S0;
		rq.adr.channel = 0;
		l2->ch.st->dev->D.ctrl(&l2->ch.st->dev->D, OPEN_CHANNEL, &rq);
		break;
	case ISDN_P_LAPD_TE:
		test_and_set_bit(FLG_LAPD, &l2->flag);
		test_and_set_bit(FLG_MOD128, &l2->flag);
		test_and_set_bit(FLG_ORIG, &l2->flag);
		l2->sapi = sapi;
		l2->maxlen = MAX_DFRAME_LEN;
		if (test_bit(OPTION_L2_PMX, &options))
			l2->window = 7;
		else
			l2->window = 1;
		if (test_bit(OPTION_L2_PTP, &options))
			test_and_set_bit(FLG_PTP, &l2->flag);
		if (test_bit(OPTION_L2_FIXEDTEI, &options))
			test_and_set_bit(FLG_FIXED_TEI, &l2->flag);
		l2->tei = tei;
		l2->T200 = 1000;
		l2->N200 = 3;
		l2->T203 = 10000;
		if (test_bit(OPTION_L2_PMX, &options))
			rq.protocol = ISDN_P_TE_E1;
		else
			rq.protocol = ISDN_P_TE_S0;
		rq.adr.channel = 0;
		l2->ch.st->dev->D.ctrl(&l2->ch.st->dev->D, OPEN_CHANNEL, &rq);
		break;
	case ISDN_P_B_X75SLP:
		test_and_set_bit(FLG_LAPB, &l2->flag);
		l2->window = 7;
		l2->maxlen = MAX_DATA_SIZE;
		l2->T200 = 1000;
		l2->N200 = 4;
		l2->T203 = 5000;
		l2->addr.A = 3;
		l2->addr.B = 1;
		break;
	default:
		printk(KERN_ERR "layer2 create failed prt %x\n",
		       protocol);
		kfree(l2);
		return NULL;
	}
	skb_queue_head_init(&l2->i_queue);
	skb_queue_head_init(&l2->ui_queue);
	skb_queue_head_init(&l2->down_queue);
	skb_queue_head_init(&l2->tmp_queue);
	InitWin(l2);
	l2->l2m.fsm = &l2fsm;
	if (test_bit(FLG_LAPB, &l2->flag) ||
	    test_bit(FLG_FIXED_TEI, &l2->flag) ||
	    test_bit(FLG_LAPD_NET, &l2->flag))
		l2->l2m.state = ST_L2_4;
	else
		l2->l2m.state = ST_L2_1;
	l2->l2m.debug = *debug;
	l2->l2m.userdata = l2;
	l2->l2m.userint = 0;
	l2->l2m.printdebug = l2m_debug;

	mISDN_FsmInitTimer(&l2->l2m, &l2->t200);
	mISDN_FsmInitTimer(&l2->l2m, &l2->t203);
	return l2;
}

static int
x75create(struct channel_req *crq)
{
	struct layer2	*l2;

	if (crq->protocol != ISDN_P_B_X75SLP)
		return -EPROTONOSUPPORT;
	l2 = create_l2(crq->ch, crq->protocol, 0, 0, 0);
	if (!l2)
		return -ENOMEM;
	crq->ch = &l2->ch;
	crq->protocol = ISDN_P_B_HDLC;
	return 0;
}

static struct Bprotocol X75SLP = {
	.Bprotocols = (1 << (ISDN_P_B_X75SLP & ISDN_P_B_MASK)),
	.name = "X75SLP",
	.create = x75create
};

int
Isdnl2_Init(u_int *deb)
{
	int res;
	debug = deb;
	mISDN_register_Bprotocol(&X75SLP);
	l2fsm.state_count = L2_STATE_COUNT;
	l2fsm.event_count = L2_EVENT_COUNT;
	l2fsm.strEvent = strL2Event;
	l2fsm.strState = strL2State;
	res = mISDN_FsmNew(&l2fsm, L2FnList, ARRAY_SIZE(L2FnList));
	if (res)
		goto error;
	res = TEIInit(deb);
	if (res)
		goto error_fsm;
	return 0;

error_fsm:
	mISDN_FsmFree(&l2fsm);
error:
	mISDN_unregister_Bprotocol(&X75SLP);
	return res;
}

void
Isdnl2_cleanup(void)
{
	mISDN_unregister_Bprotocol(&X75SLP);
	TEIFree();
	mISDN_FsmFree(&l2fsm);
}