Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
can.h
Go to the documentation of this file.
1 /*
2  * linux/can.h
3  *
4  * Definitions for CAN network layer (socket addr / CAN frame / CAN filter)
5  *
6  * Authors: Oliver Hartkopp <[email protected]>
7  * Urs Thuermann <[email protected]>
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 message 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 message frame flag (0 = data frame, 1 = error message)
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 #define CAN_SFF_ID_BITS 11
42 #define CAN_EFF_ID_BITS 29
43 
44 /*
45  * Controller Area Network Error Message Frame Mask structure
46  *
47  * bit 0-28 : error class mask (see include/linux/can/error.h)
48  * bit 29-31 : set to zero
49  */
51 
52 /* CAN payload length and DLC definitions according to ISO 11898-1 */
53 #define CAN_MAX_DLC 8
54 #define CAN_MAX_DLEN 8
55 
56 /* CAN FD payload length and DLC definitions according to ISO 11898-7 */
57 #define CANFD_MAX_DLC 15
58 #define CANFD_MAX_DLEN 64
59 
68 struct can_frame {
69  canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */
70  __u8 can_dlc; /* frame payload length in byte (0 .. CAN_MAX_DLEN) */
72 };
73 
74 /*
75  * defined bits for canfd_frame.flags
76  *
77  * The use of struct canfd_frame implies the Extended Data Length (EDL) bit to
78  * be set in the CAN frame bitstream on the wire. The EDL bit switch turns
79  * the CAN controllers bitstream processor into the CAN FD mode which creates
80  * two new options within the CAN FD frame specification:
81  *
82  * Bit Rate Switch - to indicate a second bitrate is/was used for the payload
83  * Error State Indicator - represents the error state of the transmitting node
84  *
85  * As the CANFD_ESI bit is internally generated by the transmitting CAN
86  * controller only the CANFD_BRS bit is relevant for real CAN controllers when
87  * building a CAN FD frame for transmission. Setting the CANFD_ESI bit can make
88  * sense for virtual CAN interfaces to test applications with echoed frames.
89  */
90 #define CANFD_BRS 0x01 /* bit rate switch (second bitrate for payload data) */
91 #define CANFD_ESI 0x02 /* error state indicator of the transmitting node */
92 
102 struct canfd_frame {
103  canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */
104  __u8 len; /* frame payload length in byte */
105  __u8 flags; /* additional flags for CAN FD */
106  __u8 __res0; /* reserved / padding */
107  __u8 __res1; /* reserved / padding */
109 };
110 
111 #define CAN_MTU (sizeof(struct can_frame))
112 #define CANFD_MTU (sizeof(struct canfd_frame))
113 
114 /* particular protocols of the protocol family PF_CAN */
115 #define CAN_RAW 1 /* RAW sockets */
116 #define CAN_BCM 2 /* Broadcast Manager */
117 #define CAN_TP16 3 /* VAG Transport Protocol v1.6 */
118 #define CAN_TP20 4 /* VAG Transport Protocol v2.0 */
119 #define CAN_MCNET 5 /* Bosch MCNet */
120 #define CAN_ISOTP 6 /* ISO 15765-2 Transport Protocol */
121 #define CAN_NPROTO 7
122 
123 #define SOL_CAN_BASE 100
124 
131 struct sockaddr_can {
134  union {
135  /* transport protocol class address information (e.g. ISOTP) */
136  struct { canid_t rx_id, tx_id; } tp;
137 
138  /* reserved for future CAN protocols address information */
139  } can_addr;
140 };
141 
155 struct can_filter {
158 };
159 
160 #define CAN_INV_FILTER 0x20000000U /* to be set in can_filter.can_id */
161 
162 #endif /* CAN_H */