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1/* SPDX-License-Identifier: ((GPL-2.0-only WITH Linux-syscall-note) OR BSD-3-Clause) */2/*3 * linux/can.h4 *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 Research10 * All rights reserved.11 *12 * Redistribution and use in source and binary forms, with or without13 * modification, are permitted provided that the following conditions14 * are met:15 * 1. Redistributions of source code must retain the above copyright16 * notice, this list of conditions and the following disclaimer.17 * 2. Redistributions in binary form must reproduce the above copyright18 * notice, this list of conditions and the following disclaimer in the19 * documentation and/or other materials provided with the distribution.20 * 3. Neither the name of Volkswagen nor the names of its contributors21 * may be used to endorse or promote products derived from this software22 * without specific prior written permission.23 *24 * Alternatively, provided that this notice is retained in full, this25 * software may be distributed under the terms of the GNU General26 * Public License ("GPL") version 2, in which case the provisions of the27 * GPL apply INSTEAD OF those given above.28 *29 * The provided data structures and external interfaces from this code30 * are not restricted to be used by modules with a GPL compatible license.31 *32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT36 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,37 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT38 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,39 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY40 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT41 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE42 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH43 * DAMAGE.44 */45 46#ifndef _UAPI_CAN_H47#define _UAPI_CAN_H48 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 structure68 *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 */74typedef __u32 canid_t;75 76#define CAN_SFF_ID_BITS 1177#define CAN_EFF_ID_BITS 2978#define CANXL_PRIO_BITS CAN_SFF_ID_BITS79 80/*81 * Controller Area Network Error Message Frame Mask structure82 *83 * bit 0-28 : error class mask (see include/uapi/linux/can/error.h)84 * bit 29-31 : set to zero85 */86typedef __u32 can_err_mask_t;87 88/* CAN payload length and DLC definitions according to ISO 11898-1 */89#define CAN_MAX_DLC 890#define CAN_MAX_RAW_DLC 1591#define CAN_MAX_DLEN 892 93/* CAN FD payload length and DLC definitions according to ISO 11898-7 */94#define CANFD_MAX_DLC 1595#define CANFD_MAX_DLEN 6496 97/*98 * CAN XL payload length and DLC definitions according to ISO 11898-199 * CAN XL DLC ranges from 0 .. 2047 => data length from 1 .. 2048 byte100 */101#define CANXL_MIN_DLC 0102#define CANXL_MAX_DLC 2047103#define CANXL_MAX_DLC_MASK 0x07FF104#define CANXL_MIN_DLEN 1105#define CANXL_MAX_DLEN 2048106 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 definition110 * @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: padding113 * @__res0: reserved / padding114 * @len8_dlc: optional DLC value (9 .. 15) at 8 byte payload length115 * len8_dlc contains values from 9 .. 15 when the payload length is116 * 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 */120struct 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 that125 * name for legacy support126 */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.flags138 *139 * The use of struct canfd_frame implies the FD Frame (FDF) bit to140 * be set in the CAN frame bitstream on the wire. The FDF bit switch turns141 * the CAN controllers bitstream processor into the CAN FD mode which creates142 * two new options within the CAN FD frame specification:143 *144 * Bit Rate Switch - to indicate a second bitrate is/was used for the payload145 * Error State Indicator - represents the error state of the transmitting node146 *147 * As the CANFD_ESI bit is internally generated by the transmitting CAN148 * controller only the CANFD_BRS bit is relevant for real CAN controllers when149 * building a CAN FD frame for transmission. Setting the CANFD_ESI bit can make150 * sense for virtual CAN interfaces to test applications with echoed frames.151 *152 * The struct can_frame and struct canfd_frame intentionally share the same153 * 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 gets155 * lost. CANFD_FDF allows programmers to mark CAN FD frames in the case of156 * 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 FD158 * 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 structure166 * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition167 * @len: frame payload length in byte (0 .. CANFD_MAX_DLEN)168 * @flags: additional flags for CAN FD169 * @__res0: reserved / padding170 * @__res1: reserved / padding171 * @data: CAN FD frame payload (up to CANFD_MAX_DLEN byte)172 */173struct 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.flags184 *185 * The canxl_frame.flags element contains two bits CANXL_XLF and CANXL_SEC186 * 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 checks189 * 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 structure203 * @prio: 11 bit arbitration priority with zero'ed CAN_*_FLAG flags / VCID204 * @flags: additional flags for CAN XL205 * @sdt: SDU (service data unit) type206 * @len: frame payload length in byte (CANXL_MIN_DLEN .. CANXL_MAX_DLEN)207 * @af: acceptance field208 * @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 */212struct 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_MTU227 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 8237 238#define SOL_CAN_BASE 100239 240/**241 * struct sockaddr_can - the sockaddr structure for CAN sockets242 * @can_family: address family number AF_CAN.243 * @can_ifindex: CAN network interface index.244 * @can_addr: protocol specific address information245 */246struct 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 0260 * 8 bit: PF261 * 1 bit: DP262 * 1 bit: reserved263 */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, when281 *282 * <received_can_id> & mask == can_id & mask283 *284 * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can285 * filter for error message frames (CAN_ERR_FLAG bit set in mask).286 */287struct 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 */295