can.h (9268B)
1/* SPDX-License-Identifier: ((GPL-2.0-only WITH Linux-syscall-note) OR BSD-3-Clause) */ 2/* 3 * linux/can.h 4 * 5 * Definitions for CAN network layer (socket addr / CAN frame / CAN filter) 6 * 7 * Authors: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> 8 * Urs Thuermann <urs.thuermann@volkswagen.de> 9 * Copyright (c) 2002-2007 Volkswagen Group Electronic Research 10 * All rights reserved. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of Volkswagen nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * Alternatively, provided that this notice is retained in full, this 25 * software may be distributed under the terms of the GNU General 26 * Public License ("GPL") version 2, in which case the provisions of the 27 * GPL apply INSTEAD OF those given above. 28 * 29 * The provided data structures and external interfaces from this code 30 * are not restricted to be used by modules with a GPL compatible license. 31 * 32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 36 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 37 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 38 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 39 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 40 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 41 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 42 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 43 * DAMAGE. 44 */ 45 46#ifndef _UAPI_CAN_H 47#define _UAPI_CAN_H 48 49#include <linux/types.h> 50#include <linux/socket.h> 51 52/* controller area network (CAN) kernel definitions */ 53 54/* special address description flags for the CAN_ID */ 55#define CAN_EFF_FLAG 0x80000000U /* EFF/SFF is set in the MSB */ 56#define CAN_RTR_FLAG 0x40000000U /* remote transmission request */ 57#define CAN_ERR_FLAG 0x20000000U /* error message frame */ 58 59/* valid bits in CAN ID for frame formats */ 60#define CAN_SFF_MASK 0x000007FFU /* standard frame format (SFF) */ 61#define CAN_EFF_MASK 0x1FFFFFFFU /* extended frame format (EFF) */ 62#define CAN_ERR_MASK 0x1FFFFFFFU /* omit EFF, RTR, ERR flags */ 63 64/* 65 * Controller Area Network Identifier structure 66 * 67 * bit 0-28 : CAN identifier (11/29 bit) 68 * bit 29 : error message frame flag (0 = data frame, 1 = error message) 69 * bit 30 : remote transmission request flag (1 = rtr frame) 70 * bit 31 : frame format flag (0 = standard 11 bit, 1 = extended 29 bit) 71 */ 72typedef __u32 canid_t; 73 74#define CAN_SFF_ID_BITS 11 75#define CAN_EFF_ID_BITS 29 76 77/* 78 * Controller Area Network Error Message Frame Mask structure 79 * 80 * bit 0-28 : error class mask (see include/uapi/linux/can/error.h) 81 * bit 29-31 : set to zero 82 */ 83typedef __u32 can_err_mask_t; 84 85/* CAN payload length and DLC definitions according to ISO 11898-1 */ 86#define CAN_MAX_DLC 8 87#define CAN_MAX_RAW_DLC 15 88#define CAN_MAX_DLEN 8 89 90/* CAN FD payload length and DLC definitions according to ISO 11898-7 */ 91#define CANFD_MAX_DLC 15 92#define CANFD_MAX_DLEN 64 93 94/** 95 * struct can_frame - Classical CAN frame structure (aka CAN 2.0B) 96 * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition 97 * @len: CAN frame payload length in byte (0 .. 8) 98 * @can_dlc: deprecated name for CAN frame payload length in byte (0 .. 8) 99 * @__pad: padding 100 * @__res0: reserved / padding 101 * @len8_dlc: optional DLC value (9 .. 15) at 8 byte payload length 102 * len8_dlc contains values from 9 .. 15 when the payload length is 103 * 8 bytes but the DLC value (see ISO 11898-1) is greater then 8. 104 * CAN_CTRLMODE_CC_LEN8_DLC flag has to be enabled in CAN driver. 105 * @data: CAN frame payload (up to 8 byte) 106 */ 107struct can_frame { 108 canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */ 109 union { 110 /* CAN frame payload length in byte (0 .. CAN_MAX_DLEN) 111 * was previously named can_dlc so we need to carry that 112 * name for legacy support 113 */ 114 __u8 len; 115 __u8 can_dlc; /* deprecated */ 116 } __attribute__((packed)); /* disable padding added in some ABIs */ 117 __u8 __pad; /* padding */ 118 __u8 __res0; /* reserved / padding */ 119 __u8 len8_dlc; /* optional DLC for 8 byte payload length (9 .. 15) */ 120 __u8 data[CAN_MAX_DLEN] __attribute__((aligned(8))); 121}; 122 123/* 124 * defined bits for canfd_frame.flags 125 * 126 * The use of struct canfd_frame implies the FD Frame (FDF) bit to 127 * be set in the CAN frame bitstream on the wire. The FDF bit switch turns 128 * the CAN controllers bitstream processor into the CAN FD mode which creates 129 * two new options within the CAN FD frame specification: 130 * 131 * Bit Rate Switch - to indicate a second bitrate is/was used for the payload 132 * Error State Indicator - represents the error state of the transmitting node 133 * 134 * As the CANFD_ESI bit is internally generated by the transmitting CAN 135 * controller only the CANFD_BRS bit is relevant for real CAN controllers when 136 * building a CAN FD frame for transmission. Setting the CANFD_ESI bit can make 137 * sense for virtual CAN interfaces to test applications with echoed frames. 138 * 139 * The struct can_frame and struct canfd_frame intentionally share the same 140 * layout to be able to write CAN frame content into a CAN FD frame structure. 141 * When this is done the former differentiation via CAN_MTU / CANFD_MTU gets 142 * lost. CANFD_FDF allows programmers to mark CAN FD frames in the case of 143 * using struct canfd_frame for mixed CAN / CAN FD content (dual use). 144 * N.B. the Kernel APIs do NOT provide mixed CAN / CAN FD content inside of 145 * struct canfd_frame therefore the CANFD_FDF flag is disregarded by Linux. 146 */ 147#define CANFD_BRS 0x01 /* bit rate switch (second bitrate for payload data) */ 148#define CANFD_ESI 0x02 /* error state indicator of the transmitting node */ 149#define CANFD_FDF 0x04 /* mark CAN FD for dual use of struct canfd_frame */ 150 151/** 152 * struct canfd_frame - CAN flexible data rate frame structure 153 * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition 154 * @len: frame payload length in byte (0 .. CANFD_MAX_DLEN) 155 * @flags: additional flags for CAN FD 156 * @__res0: reserved / padding 157 * @__res1: reserved / padding 158 * @data: CAN FD frame payload (up to CANFD_MAX_DLEN byte) 159 */ 160struct canfd_frame { 161 canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */ 162 __u8 len; /* frame payload length in byte */ 163 __u8 flags; /* additional flags for CAN FD */ 164 __u8 __res0; /* reserved / padding */ 165 __u8 __res1; /* reserved / padding */ 166 __u8 data[CANFD_MAX_DLEN] __attribute__((aligned(8))); 167}; 168 169#define CAN_MTU (sizeof(struct can_frame)) 170#define CANFD_MTU (sizeof(struct canfd_frame)) 171 172/* particular protocols of the protocol family PF_CAN */ 173#define CAN_RAW 1 /* RAW sockets */ 174#define CAN_BCM 2 /* Broadcast Manager */ 175#define CAN_TP16 3 /* VAG Transport Protocol v1.6 */ 176#define CAN_TP20 4 /* VAG Transport Protocol v2.0 */ 177#define CAN_MCNET 5 /* Bosch MCNet */ 178#define CAN_ISOTP 6 /* ISO 15765-2 Transport Protocol */ 179#define CAN_J1939 7 /* SAE J1939 */ 180#define CAN_NPROTO 8 181 182#define SOL_CAN_BASE 100 183 184/** 185 * struct sockaddr_can - the sockaddr structure for CAN sockets 186 * @can_family: address family number AF_CAN. 187 * @can_ifindex: CAN network interface index. 188 * @can_addr: protocol specific address information 189 */ 190struct sockaddr_can { 191 __kernel_sa_family_t can_family; 192 int can_ifindex; 193 union { 194 /* transport protocol class address information (e.g. ISOTP) */ 195 struct { canid_t rx_id, tx_id; } tp; 196 197 /* J1939 address information */ 198 struct { 199 /* 8 byte name when using dynamic addressing */ 200 __u64 name; 201 202 /* pgn: 203 * 8 bit: PS in PDU2 case, else 0 204 * 8 bit: PF 205 * 1 bit: DP 206 * 1 bit: reserved 207 */ 208 __u32 pgn; 209 210 /* 1 byte address */ 211 __u8 addr; 212 } j1939; 213 214 /* reserved for future CAN protocols address information */ 215 } can_addr; 216}; 217 218/** 219 * struct can_filter - CAN ID based filter in can_register(). 220 * @can_id: relevant bits of CAN ID which are not masked out. 221 * @can_mask: CAN mask (see description) 222 * 223 * Description: 224 * A filter matches, when 225 * 226 * <received_can_id> & mask == can_id & mask 227 * 228 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can 229 * filter for error message frames (CAN_ERR_FLAG bit set in mask). 230 */ 231struct can_filter { 232 canid_t can_id; 233 canid_t can_mask; 234}; 235 236#define CAN_INV_FILTER 0x20000000U /* to be set in can_filter.can_id */ 237#define CAN_RAW_FILTER_MAX 512 /* maximum number of can_filter set via setsockopt() */ 238 239#endif /* !_UAPI_CAN_H */