xref: /openbmc/linux/include/net/lapb.h (revision cfbb9be8)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LAPB_H
3 #define _LAPB_H
4 #include <linux/lapb.h>
5 #include <linux/refcount.h>
6 
7 #define	LAPB_HEADER_LEN	20		/* LAPB over Ethernet + a bit more */
8 
9 #define	LAPB_ACK_PENDING_CONDITION	0x01
10 #define	LAPB_REJECT_CONDITION		0x02
11 #define	LAPB_PEER_RX_BUSY_CONDITION	0x04
12 
13 /* Control field templates */
14 #define	LAPB_I		0x00	/* Information frames */
15 #define	LAPB_S		0x01	/* Supervisory frames */
16 #define	LAPB_U		0x03	/* Unnumbered frames */
17 
18 #define	LAPB_RR		0x01	/* Receiver ready */
19 #define	LAPB_RNR	0x05	/* Receiver not ready */
20 #define	LAPB_REJ	0x09	/* Reject */
21 
22 #define	LAPB_SABM	0x2F	/* Set Asynchronous Balanced Mode */
23 #define	LAPB_SABME	0x6F	/* Set Asynchronous Balanced Mode Extended */
24 #define	LAPB_DISC	0x43	/* Disconnect */
25 #define	LAPB_DM		0x0F	/* Disconnected mode */
26 #define	LAPB_UA		0x63	/* Unnumbered acknowledge */
27 #define	LAPB_FRMR	0x87	/* Frame reject */
28 
29 #define LAPB_ILLEGAL	0x100	/* Impossible to be a real frame type */
30 
31 #define	LAPB_SPF	0x10	/* Poll/final bit for standard LAPB */
32 #define	LAPB_EPF	0x01	/* Poll/final bit for extended LAPB */
33 
34 #define	LAPB_FRMR_W	0x01	/* Control field invalid	*/
35 #define	LAPB_FRMR_X	0x02	/* I field invalid		*/
36 #define	LAPB_FRMR_Y	0x04	/* I field too long		*/
37 #define	LAPB_FRMR_Z	0x08	/* Invalid N(R)			*/
38 
39 #define	LAPB_POLLOFF	0
40 #define	LAPB_POLLON	1
41 
42 /* LAPB C-bit */
43 #define LAPB_COMMAND	1
44 #define LAPB_RESPONSE	2
45 
46 #define	LAPB_ADDR_A	0x03
47 #define	LAPB_ADDR_B	0x01
48 #define	LAPB_ADDR_C	0x0F
49 #define	LAPB_ADDR_D	0x07
50 
51 /* Define Link State constants. */
52 enum {
53 	LAPB_STATE_0,	/* Disconnected State		*/
54 	LAPB_STATE_1,	/* Awaiting Connection State	*/
55 	LAPB_STATE_2,	/* Awaiting Disconnection State	*/
56 	LAPB_STATE_3,	/* Data Transfer State		*/
57 	LAPB_STATE_4	/* Frame Reject State		*/
58 };
59 
60 #define	LAPB_DEFAULT_MODE		(LAPB_STANDARD | LAPB_SLP | LAPB_DTE)
61 #define	LAPB_DEFAULT_WINDOW		7		/* Window=7 */
62 #define	LAPB_DEFAULT_T1			(5 * HZ)	/* T1=5s    */
63 #define	LAPB_DEFAULT_T2			(1 * HZ)	/* T2=1s    */
64 #define	LAPB_DEFAULT_N2			20		/* N2=20    */
65 
66 #define	LAPB_SMODULUS	8
67 #define	LAPB_EMODULUS	128
68 
69 /*
70  *	Information about the current frame.
71  */
72 struct lapb_frame {
73 	unsigned short		type;		/* Parsed type		*/
74 	unsigned short		nr, ns;		/* N(R), N(S)		*/
75 	unsigned char		cr;		/* Command/Response	*/
76 	unsigned char		pf;		/* Poll/Final		*/
77 	unsigned char		control[2];	/* Original control data*/
78 };
79 
80 /*
81  *	The per LAPB connection control structure.
82  */
83 struct lapb_cb {
84 	struct list_head	node;
85 	struct net_device	*dev;
86 
87 	/* Link status fields */
88 	unsigned int		mode;
89 	unsigned char		state;
90 	unsigned short		vs, vr, va;
91 	unsigned char		condition;
92 	unsigned short		n2, n2count;
93 	unsigned short		t1, t2;
94 	struct timer_list	t1timer, t2timer;
95 
96 	/* Internal control information */
97 	struct sk_buff_head	write_queue;
98 	struct sk_buff_head	ack_queue;
99 	unsigned char		window;
100 	const struct lapb_register_struct *callbacks;
101 
102 	/* FRMR control information */
103 	struct lapb_frame	frmr_data;
104 	unsigned char		frmr_type;
105 
106 	refcount_t		refcnt;
107 };
108 
109 /* lapb_iface.c */
110 void lapb_connect_confirmation(struct lapb_cb *lapb, int);
111 void lapb_connect_indication(struct lapb_cb *lapb, int);
112 void lapb_disconnect_confirmation(struct lapb_cb *lapb, int);
113 void lapb_disconnect_indication(struct lapb_cb *lapb, int);
114 int lapb_data_indication(struct lapb_cb *lapb, struct sk_buff *);
115 int lapb_data_transmit(struct lapb_cb *lapb, struct sk_buff *);
116 
117 /* lapb_in.c */
118 void lapb_data_input(struct lapb_cb *lapb, struct sk_buff *);
119 
120 /* lapb_out.c */
121 void lapb_kick(struct lapb_cb *lapb);
122 void lapb_transmit_buffer(struct lapb_cb *lapb, struct sk_buff *, int);
123 void lapb_establish_data_link(struct lapb_cb *lapb);
124 void lapb_enquiry_response(struct lapb_cb *lapb);
125 void lapb_timeout_response(struct lapb_cb *lapb);
126 void lapb_check_iframes_acked(struct lapb_cb *lapb, unsigned short);
127 void lapb_check_need_response(struct lapb_cb *lapb, int, int);
128 
129 /* lapb_subr.c */
130 void lapb_clear_queues(struct lapb_cb *lapb);
131 void lapb_frames_acked(struct lapb_cb *lapb, unsigned short);
132 void lapb_requeue_frames(struct lapb_cb *lapb);
133 int lapb_validate_nr(struct lapb_cb *lapb, unsigned short);
134 int lapb_decode(struct lapb_cb *lapb, struct sk_buff *, struct lapb_frame *);
135 void lapb_send_control(struct lapb_cb *lapb, int, int, int);
136 void lapb_transmit_frmr(struct lapb_cb *lapb);
137 
138 /* lapb_timer.c */
139 void lapb_start_t1timer(struct lapb_cb *lapb);
140 void lapb_start_t2timer(struct lapb_cb *lapb);
141 void lapb_stop_t1timer(struct lapb_cb *lapb);
142 void lapb_stop_t2timer(struct lapb_cb *lapb);
143 int lapb_t1timer_running(struct lapb_cb *lapb);
144 
145 /*
146  * Debug levels.
147  *	0 = Off
148  *	1 = State Changes
149  *	2 = Packets I/O and State Changes
150  *	3 = Hex dumps, Packets I/O and State Changes.
151  */
152 #define	LAPB_DEBUG	0
153 
154 #define lapb_dbg(level, fmt, ...)			\
155 do {							\
156 	if (level < LAPB_DEBUG)				\
157 		pr_debug(fmt, ##__VA_ARGS__);		\
158 } while (0)
159 
160 #endif
161