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 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 */ 50 typedef __u32 can_err_mask_t; 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 60 /** 61 * struct can_frame - basic CAN frame structure 62 * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition 63 * @can_dlc: frame payload length in byte (0 .. 8) aka data length code 64 * N.B. the DLC field from ISO 11898-1 Chapter 8.4.2.3 has a 1:1 65 * mapping of the 'data length code' to the real payload length 66 * @data: CAN frame payload (up to 8 byte) 67 */ 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) */ 71 __u8 data[CAN_MAX_DLEN] __attribute__((aligned(8))); 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 93 /** 94 * struct canfd_frame - CAN flexible data rate frame structure 95 * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition 96 * @len: frame payload length in byte (0 .. CANFD_MAX_DLEN) 97 * @flags: additional flags for CAN FD 98 * @__res0: reserved / padding 99 * @__res1: reserved / padding 100 * @data: CAN FD frame payload (up to CANFD_MAX_DLEN byte) 101 */ 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 */ 108 __u8 data[CANFD_MAX_DLEN] __attribute__((aligned(8))); 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 100 124 125 /** 126 * struct sockaddr_can - the sockaddr structure for CAN sockets 127 * @can_family: address family number AF_CAN. 128 * @can_ifindex: CAN network interface index. 129 * @can_addr: protocol specific address information 130 */ 131 struct sockaddr_can { 132 __kernel_sa_family_t can_family; 133 int can_ifindex; 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 }; 141 142 /** 143 * struct can_filter - CAN ID based filter in can_register(). 144 * @can_id: relevant bits of CAN ID which are not masked out. 145 * @can_mask: CAN mask (see description) 146 * 147 * Description: 148 * A filter matches, when 149 * 150 * <received_can_id> & mask == can_id & mask 151 * 152 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can 153 * filter for error message frames (CAN_ERR_FLAG bit set in mask). 154 */ 155 struct can_filter { 156 canid_t can_id; 157 canid_t can_mask; 158 }; 159 160 #define CAN_INV_FILTER 0x20000000U /* to be set in can_filter.can_id */ 161 162 #endif /* CAN_H */ 163