can.h (11495B) - Raw
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 _CAN_H 47 #define _CAN_H 48 49 #include <linux/types.h> 50 #include <linux/socket.h> 51 #include <linux/stddef.h> /* for offsetof */ 52 53 /* controller area network (CAN) kernel definitions */ 54 55 /* special address description flags for the CAN_ID */ 56 #define CAN_EFF_FLAG 0x80000000U /* EFF/SFF is set in the MSB */ 57 #define CAN_RTR_FLAG 0x40000000U /* remote transmission request */ 58 #define CAN_ERR_FLAG 0x20000000U /* error message frame */ 59 60 /* valid bits in CAN ID for frame formats */ 61 #define CAN_SFF_MASK 0x000007FFU /* standard frame format (SFF) */ 62 #define CAN_EFF_MASK 0x1FFFFFFFU /* extended frame format (EFF) */ 63 #define CAN_ERR_MASK 0x1FFFFFFFU /* omit EFF, RTR, ERR flags */ 64 #define CANXL_PRIO_MASK CAN_SFF_MASK /* 11 bit priority mask */ 65 66 /* 67 * Controller Area Network Identifier structure 68 * 69 * bit 0-28 : CAN identifier (11/29 bit) 70 * bit 29 : error message frame flag (0 = data frame, 1 = error message) 71 * bit 30 : remote transmission request flag (1 = rtr frame) 72 * bit 31 : frame format flag (0 = standard 11 bit, 1 = extended 29 bit) 73 */ 74 typedef __u32 canid_t; 75 76 #define CAN_SFF_ID_BITS 11 77 #define CAN_EFF_ID_BITS 29 78 #define CANXL_PRIO_BITS CAN_SFF_ID_BITS 79 80 /* 81 * Controller Area Network Error Message Frame Mask structure 82 * 83 * bit 0-28 : error class mask (see include/uapi/linux/can/error.h) 84 * bit 29-31 : set to zero 85 */ 86 typedef __u32 can_err_mask_t; 87 88 /* CAN payload length and DLC definitions according to ISO 11898-1 */ 89 #define CAN_MAX_DLC 8 90 #define CAN_MAX_RAW_DLC 15 91 #define CAN_MAX_DLEN 8 92 93 /* CAN FD payload length and DLC definitions according to ISO 11898-7 */ 94 #define CANFD_MAX_DLC 15 95 #define CANFD_MAX_DLEN 64 96 97 /* 98 * CAN XL payload length and DLC definitions according to ISO 11898-1 99 * CAN XL DLC ranges from 0 .. 2047 => data length from 1 .. 2048 byte 100 */ 101 #define CANXL_MIN_DLC 0 102 #define CANXL_MAX_DLC 2047 103 #define CANXL_MAX_DLC_MASK 0x07FF 104 #define CANXL_MIN_DLEN 1 105 #define CANXL_MAX_DLEN 2048 106 107 /** 108 * struct can_frame - Classical CAN frame structure (aka CAN 2.0B) 109 * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition 110 * @len: CAN frame payload length in byte (0 .. 8) 111 * @can_dlc: deprecated name for CAN frame payload length in byte (0 .. 8) 112 * @__pad: padding 113 * @__res0: reserved / padding 114 * @len8_dlc: optional DLC value (9 .. 15) at 8 byte payload length 115 * len8_dlc contains values from 9 .. 15 when the payload length is 116 * 8 bytes but the DLC value (see ISO 11898-1) is greater then 8. 117 * CAN_CTRLMODE_CC_LEN8_DLC flag has to be enabled in CAN driver. 118 * @data: CAN frame payload (up to 8 byte) 119 */ 120 struct can_frame { 121 canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */ 122 union { 123 /* CAN frame payload length in byte (0 .. CAN_MAX_DLEN) 124 * was previously named can_dlc so we need to carry that 125 * name for legacy support 126 */ 127 __u8 len; 128 __u8 can_dlc; /* deprecated */ 129 } __attribute__((packed)); /* disable padding added in some ABIs */ 130 __u8 __pad; /* padding */ 131 __u8 __res0; /* reserved / padding */ 132 __u8 len8_dlc; /* optional DLC for 8 byte payload length (9 .. 15) */ 133 __u8 data[CAN_MAX_DLEN] __attribute__((aligned(8))); 134 }; 135 136 /* 137 * defined bits for canfd_frame.flags 138 * 139 * The use of struct canfd_frame implies the FD Frame (FDF) bit to 140 * be set in the CAN frame bitstream on the wire. The FDF bit switch turns 141 * the CAN controllers bitstream processor into the CAN FD mode which creates 142 * two new options within the CAN FD frame specification: 143 * 144 * Bit Rate Switch - to indicate a second bitrate is/was used for the payload 145 * Error State Indicator - represents the error state of the transmitting node 146 * 147 * As the CANFD_ESI bit is internally generated by the transmitting CAN 148 * controller only the CANFD_BRS bit is relevant for real CAN controllers when 149 * building a CAN FD frame for transmission. Setting the CANFD_ESI bit can make 150 * sense for virtual CAN interfaces to test applications with echoed frames. 151 * 152 * The struct can_frame and struct canfd_frame intentionally share the same 153 * layout to be able to write CAN frame content into a CAN FD frame structure. 154 * When this is done the former differentiation via CAN_MTU / CANFD_MTU gets 155 * lost. CANFD_FDF allows programmers to mark CAN FD frames in the case of 156 * using struct canfd_frame for mixed CAN / CAN FD content (dual use). 157 * Since the introduction of CAN XL the CANFD_FDF flag is set in all CAN FD 158 * frame structures provided by the CAN subsystem of the Linux kernel. 159 */ 160 #define CANFD_BRS 0x01 /* bit rate switch (second bitrate for payload data) */ 161 #define CANFD_ESI 0x02 /* error state indicator of the transmitting node */ 162 #define CANFD_FDF 0x04 /* mark CAN FD for dual use of struct canfd_frame */ 163 164 /** 165 * struct canfd_frame - CAN flexible data rate frame structure 166 * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition 167 * @len: frame payload length in byte (0 .. CANFD_MAX_DLEN) 168 * @flags: additional flags for CAN FD 169 * @__res0: reserved / padding 170 * @__res1: reserved / padding 171 * @data: CAN FD frame payload (up to CANFD_MAX_DLEN byte) 172 */ 173 struct canfd_frame { 174 canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */ 175 __u8 len; /* frame payload length in byte */ 176 __u8 flags; /* additional flags for CAN FD */ 177 __u8 __res0; /* reserved / padding */ 178 __u8 __res1; /* reserved / padding */ 179 __u8 data[CANFD_MAX_DLEN] __attribute__((aligned(8))); 180 }; 181 182 /* 183 * defined bits for canxl_frame.flags 184 * 185 * The canxl_frame.flags element contains two bits CANXL_XLF and CANXL_SEC 186 * and shares the relative position of the struct can[fd]_frame.len element. 187 * The CANXL_XLF bit ALWAYS needs to be set to indicate a valid CAN XL frame. 188 * As a side effect setting this bit intentionally breaks the length checks 189 * for Classical CAN and CAN FD frames. 190 * 191 * Undefined bits in canxl_frame.flags are reserved and shall be set to zero. 192 */ 193 #define CANXL_XLF 0x80 /* mandatory CAN XL frame flag (must always be set!) */ 194 #define CANXL_SEC 0x01 /* Simple Extended Content (security/segmentation) */ 195 196 /* the 8-bit VCID is optionally placed in the canxl_frame.prio element */ 197 #define CANXL_VCID_OFFSET 16 /* bit offset of VCID in prio element */ 198 #define CANXL_VCID_VAL_MASK 0xFFUL /* VCID is an 8-bit value */ 199 #define CANXL_VCID_MASK (CANXL_VCID_VAL_MASK << CANXL_VCID_OFFSET) 200 201 /** 202 * struct canxl_frame - CAN with e'X'tended frame 'L'ength frame structure 203 * @prio: 11 bit arbitration priority with zero'ed CAN_*_FLAG flags / VCID 204 * @flags: additional flags for CAN XL 205 * @sdt: SDU (service data unit) type 206 * @len: frame payload length in byte (CANXL_MIN_DLEN .. CANXL_MAX_DLEN) 207 * @af: acceptance field 208 * @data: CAN XL frame payload (CANXL_MIN_DLEN .. CANXL_MAX_DLEN byte) 209 * 210 * @prio shares the same position as @can_id from struct can[fd]_frame. 211 */ 212 struct canxl_frame { 213 canid_t prio; /* 11 bit priority for arbitration / 8 bit VCID */ 214 __u8 flags; /* additional flags for CAN XL */ 215 __u8 sdt; /* SDU (service data unit) type */ 216 __u16 len; /* frame payload length in byte */ 217 __u32 af; /* acceptance field */ 218 __u8 data[CANXL_MAX_DLEN]; 219 }; 220 221 #define CAN_MTU (sizeof(struct can_frame)) 222 #define CANFD_MTU (sizeof(struct canfd_frame)) 223 #define CANXL_MTU (sizeof(struct canxl_frame)) 224 #define CANXL_HDR_SIZE (offsetof(struct canxl_frame, data)) 225 #define CANXL_MIN_MTU (CANXL_HDR_SIZE + 64) 226 #define CANXL_MAX_MTU CANXL_MTU 227 228 /* particular protocols of the protocol family PF_CAN */ 229 #define CAN_RAW 1 /* RAW sockets */ 230 #define CAN_BCM 2 /* Broadcast Manager */ 231 #define CAN_TP16 3 /* VAG Transport Protocol v1.6 */ 232 #define CAN_TP20 4 /* VAG Transport Protocol v2.0 */ 233 #define CAN_MCNET 5 /* Bosch MCNet */ 234 #define CAN_ISOTP 6 /* ISO 15765-2 Transport Protocol */ 235 #define CAN_J1939 7 /* SAE J1939 */ 236 #define CAN_NPROTO 8 237 238 #define SOL_CAN_BASE 100 239 240 /** 241 * struct sockaddr_can - the sockaddr structure for CAN sockets 242 * @can_family: address family number AF_CAN. 243 * @can_ifindex: CAN network interface index. 244 * @can_addr: protocol specific address information 245 */ 246 struct sockaddr_can { 247 __kernel_sa_family_t can_family; 248 int can_ifindex; 249 union { 250 /* transport protocol class address information (e.g. ISOTP) */ 251 struct { canid_t rx_id, tx_id; } tp; 252 253 /* J1939 address information */ 254 struct { 255 /* 8 byte name when using dynamic addressing */ 256 __u64 name; 257 258 /* pgn: 259 * 8 bit: PS in PDU2 case, else 0 260 * 8 bit: PF 261 * 1 bit: DP 262 * 1 bit: reserved 263 */ 264 __u32 pgn; 265 266 /* 1 byte address */ 267 __u8 addr; 268 } j1939; 269 270 /* reserved for future CAN protocols address information */ 271 } can_addr; 272 }; 273 274 /** 275 * struct can_filter - CAN ID based filter in can_register(). 276 * @can_id: relevant bits of CAN ID which are not masked out. 277 * @can_mask: CAN mask (see description) 278 * 279 * Description: 280 * A filter matches, when 281 * 282 * <received_can_id> & mask == can_id & mask 283 * 284 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can 285 * filter for error message frames (CAN_ERR_FLAG bit set in mask). 286 */ 287 struct can_filter { 288 canid_t can_id; 289 canid_t can_mask; 290 }; 291 292 #define CAN_INV_FILTER 0x20000000U /* to be set in can_filter.can_id */ 293 294 #endif /* !_UAPI_CAN_H */