1 /*
2  * linux/can.h
3  *
4  * Definitions for CAN network layer (socket addr / CAN frame / CAN filter)
5  *
6  * Authors: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
7  *          Urs Thuermann   <urs.thuermann@volkswagen.de>
8  * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
9  * All rights reserved.
10  *
11  */
12 
13 #ifndef CAN_H
14 #define CAN_H
15 
16 #include <linux/types.h>
17 #include <linux/socket.h>
18 
19 /* controller area network (CAN) kernel definitions */
20 
21 /* special address description flags for the CAN_ID */
22 #define CAN_EFF_FLAG 0x80000000U /* EFF/SFF is set in the MSB */
23 #define CAN_RTR_FLAG 0x40000000U /* remote transmission request */
24 #define CAN_ERR_FLAG 0x20000000U /* error frame */
25 
26 /* valid bits in CAN ID for frame formats */
27 #define CAN_SFF_MASK 0x000007FFU /* standard frame format (SFF) */
28 #define CAN_EFF_MASK 0x1FFFFFFFU /* extended frame format (EFF) */
29 #define CAN_ERR_MASK 0x1FFFFFFFU /* omit EFF, RTR, ERR flags */
30 
31 /*
32  * Controller Area Network Identifier structure
33  *
34  * bit 0-28	: CAN identifier (11/29 bit)
35  * bit 29	: error frame flag (0 = data frame, 1 = error frame)
36  * bit 30	: remote transmission request flag (1 = rtr frame)
37  * bit 31	: frame format flag (0 = standard 11 bit, 1 = extended 29 bit)
38  */
39 typedef __u32 canid_t;
40 
41 /*
42  * Controller Area Network Error Frame Mask structure
43  *
44  * bit 0-28	: error class mask (see include/linux/can/error.h)
45  * bit 29-31	: set to zero
46  */
47 typedef __u32 can_err_mask_t;
48 
49 /**
50  * struct can_frame - basic CAN frame structure
51  * @can_id:  the CAN ID of the frame and CAN_*_FLAG flags, see above.
52  * @can_dlc: the data length field of the CAN frame
53  * @data:    the CAN frame payload.
54  */
55 struct can_frame {
56 	canid_t can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */
57 	__u8    can_dlc; /* data length code: 0 .. 8 */
58 	__u8    data[8] __attribute__((aligned(8)));
59 };
60 
61 /* particular protocols of the protocol family PF_CAN */
62 #define CAN_RAW		1 /* RAW sockets */
63 #define CAN_BCM		2 /* Broadcast Manager */
64 #define CAN_TP16	3 /* VAG Transport Protocol v1.6 */
65 #define CAN_TP20	4 /* VAG Transport Protocol v2.0 */
66 #define CAN_MCNET	5 /* Bosch MCNet */
67 #define CAN_ISOTP	6 /* ISO 15765-2 Transport Protocol */
68 #define CAN_NPROTO	7
69 
70 #define SOL_CAN_BASE 100
71 
72 /**
73  * struct sockaddr_can - the sockaddr structure for CAN sockets
74  * @can_family:  address family number AF_CAN.
75  * @can_ifindex: CAN network interface index.
76  * @can_addr:    protocol specific address information
77  */
78 struct sockaddr_can {
79 	__kernel_sa_family_t can_family;
80 	int         can_ifindex;
81 	union {
82 		/* transport protocol class address information (e.g. ISOTP) */
83 		struct { canid_t rx_id, tx_id; } tp;
84 
85 		/* reserved for future CAN protocols address information */
86 	} can_addr;
87 };
88 
89 /**
90  * struct can_filter - CAN ID based filter in can_register().
91  * @can_id:   relevant bits of CAN ID which are not masked out.
92  * @can_mask: CAN mask (see description)
93  *
94  * Description:
95  * A filter matches, when
96  *
97  *          <received_can_id> & mask == can_id & mask
98  *
99  * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
100  * filter for error frames (CAN_ERR_FLAG bit set in mask).
101  */
102 struct can_filter {
103 	canid_t can_id;
104 	canid_t can_mask;
105 };
106 
107 #define CAN_INV_FILTER 0x20000000U /* to be set in can_filter.can_id */
108 
109 #endif /* CAN_H */
110