/* SPDX-License-Identifier: ((GPL-2.0-only WITH Linux-syscall-note) OR BSD-3-Clause) */ /* * linux/can.h * * Definitions for CAN network layer (socket addr / CAN frame / CAN filter) * * Authors: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> * Urs Thuermann <urs.thuermann@volkswagen.de> * Copyright (c) 2002-2007 Volkswagen Group Electronic Research * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of Volkswagen nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * Alternatively, provided that this notice is retained in full, this * software may be distributed under the terms of the GNU General * Public License ("GPL") version 2, in which case the provisions of the * GPL apply INSTEAD OF those given above. * * The provided data structures and external interfaces from this code * are not restricted to be used by modules with a GPL compatible license. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH * DAMAGE. */ #ifndef _CAN_H #define _CAN_H #include <linux/types.h> #include <linux/socket.h> #include <linux/stddef.h> /* for offsetof */ /* controller area network (CAN) kernel definitions */ /* special address description flags for the CAN_ID */ #define CAN_EFF_FLAG 0x80000000U /* EFF/SFF is set in the MSB */ #define CAN_RTR_FLAG 0x40000000U /* remote transmission request */ #define CAN_ERR_FLAG 0x20000000U /* error message frame */ /* valid bits in CAN ID for frame formats */ #define CAN_SFF_MASK 0x000007FFU /* standard frame format (SFF) */ #define CAN_EFF_MASK 0x1FFFFFFFU /* extended frame format (EFF) */ #define CAN_ERR_MASK 0x1FFFFFFFU /* omit EFF, RTR, ERR flags */ #define CANXL_PRIO_MASK CAN_SFF_MASK /* 11 bit priority mask */ /* * Controller Area Network Identifier structure * * bit 0-28 : CAN identifier (11/29 bit) * bit 29 : error message frame flag (0 = data frame, 1 = error message) * bit 30 : remote transmission request flag (1 = rtr frame) * bit 31 : frame format flag (0 = standard 11 bit, 1 = extended 29 bit) */ typedef __u32 canid_t; #define CAN_SFF_ID_BITS 11 #define CAN_EFF_ID_BITS 29 #define CANXL_PRIO_BITS CAN_SFF_ID_BITS /* * Controller Area Network Error Message Frame Mask structure * * bit 0-28 : error class mask (see include/uapi/linux/can/error.h) * bit 29-31 : set to zero */ typedef __u32 can_err_mask_t; /* CAN payload length and DLC definitions according to ISO 11898-1 */ #define CAN_MAX_DLC 8 #define CAN_MAX_RAW_DLC 15 #define CAN_MAX_DLEN 8 /* CAN FD payload length and DLC definitions according to ISO 11898-7 */ #define CANFD_MAX_DLC 15 #define CANFD_MAX_DLEN 64 /* * CAN XL payload length and DLC definitions according to ISO 11898-1 * CAN XL DLC ranges from 0 .. 2047 => data length from 1 .. 2048 byte */ #define CANXL_MIN_DLC 0 #define CANXL_MAX_DLC 2047 #define CANXL_MAX_DLC_MASK 0x07FF #define CANXL_MIN_DLEN 1 #define CANXL_MAX_DLEN 2048 /** * struct can_frame - Classical CAN frame structure (aka CAN 2.0B) * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition * @len: CAN frame payload length in byte (0 .. 8) * @can_dlc: deprecated name for CAN frame payload length in byte (0 .. 8) * @__pad: padding * @__res0: reserved / padding * @len8_dlc: optional DLC value (9 .. 15) at 8 byte payload length * len8_dlc contains values from 9 .. 15 when the payload length is * 8 bytes but the DLC value (see ISO 11898-1) is greater then 8. * CAN_CTRLMODE_CC_LEN8_DLC flag has to be enabled in CAN driver. * @data: CAN frame payload (up to 8 byte) */ struct can_frame { canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */ union { /* CAN frame payload length in byte (0 .. CAN_MAX_DLEN) * was previously named can_dlc so we need to carry that * name for legacy support */ __u8 len; __u8 can_dlc; /* deprecated */ } __attribute__((packed)); /* disable padding added in some ABIs */ __u8 __pad; /* padding */ __u8 __res0; /* reserved / padding */ __u8 len8_dlc; /* optional DLC for 8 byte payload length (9 .. 15) */ __u8 data[CAN_MAX_DLEN] __attribute__((aligned(8))); }; /* * defined bits for canfd_frame.flags * * The use of struct canfd_frame implies the FD Frame (FDF) bit to * be set in the CAN frame bitstream on the wire. The FDF bit switch turns * the CAN controllers bitstream processor into the CAN FD mode which creates * two new options within the CAN FD frame specification: * * Bit Rate Switch - to indicate a second bitrate is/was used for the payload * Error State Indicator - represents the error state of the transmitting node * * As the CANFD_ESI bit is internally generated by the transmitting CAN * controller only the CANFD_BRS bit is relevant for real CAN controllers when * building a CAN FD frame for transmission. Setting the CANFD_ESI bit can make * sense for virtual CAN interfaces to test applications with echoed frames. * * The struct can_frame and struct canfd_frame intentionally share the same * layout to be able to write CAN frame content into a CAN FD frame structure. * When this is done the former differentiation via CAN_MTU / CANFD_MTU gets * lost. CANFD_FDF allows programmers to mark CAN FD frames in the case of * using struct canfd_frame for mixed CAN / CAN FD content (dual use). * Since the introduction of CAN XL the CANFD_FDF flag is set in all CAN FD * frame structures provided by the CAN subsystem of the Linux kernel. */ #define CANFD_BRS 0x01 /* bit rate switch (second bitrate for payload data) */ #define CANFD_ESI 0x02 /* error state indicator of the transmitting node */ #define CANFD_FDF 0x04 /* mark CAN FD for dual use of struct canfd_frame */ /** * struct canfd_frame - CAN flexible data rate frame structure * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition * @len: frame payload length in byte (0 .. CANFD_MAX_DLEN) * @flags: additional flags for CAN FD * @__res0: reserved / padding * @__res1: reserved / padding * @data: CAN FD frame payload (up to CANFD_MAX_DLEN byte) */ struct canfd_frame { canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */ __u8 len; /* frame payload length in byte */ __u8 flags; /* additional flags for CAN FD */ __u8 __res0; /* reserved / padding */ __u8 __res1; /* reserved / padding */ __u8 data[CANFD_MAX_DLEN] __attribute__((aligned(8))); }; /* * defined bits for canxl_frame.flags * * The canxl_frame.flags element contains two bits CANXL_XLF and CANXL_SEC * and shares the relative position of the struct can[fd]_frame.len element. * The CANXL_XLF bit ALWAYS needs to be set to indicate a valid CAN XL frame. * As a side effect setting this bit intentionally breaks the length checks * for Classical CAN and CAN FD frames. * * Undefined bits in canxl_frame.flags are reserved and shall be set to zero. */ #define CANXL_XLF 0x80 /* mandatory CAN XL frame flag (must always be set!) */ #define CANXL_SEC 0x01 /* Simple Extended Content (security/segmentation) */ /** * struct canxl_frame - CAN with e'X'tended frame 'L'ength frame structure * @prio: 11 bit arbitration priority with zero'ed CAN_*_FLAG flags * @flags: additional flags for CAN XL * @sdt: SDU (service data unit) type * @len: frame payload length in byte (CANXL_MIN_DLEN .. CANXL_MAX_DLEN) * @af: acceptance field * @data: CAN XL frame payload (CANXL_MIN_DLEN .. CANXL_MAX_DLEN byte) * * @prio shares the same position as @can_id from struct can[fd]_frame. */ struct canxl_frame { canid_t prio; /* 11 bit priority for arbitration (canid_t) */ __u8 flags; /* additional flags for CAN XL */ __u8 sdt; /* SDU (service data unit) type */ __u16 len; /* frame payload length in byte */ __u32 af; /* acceptance field */ __u8 data[CANXL_MAX_DLEN]; }; #define CAN_MTU (sizeof(struct can_frame)) #define CANFD_MTU (sizeof(struct canfd_frame)) #define CANXL_MTU (sizeof(struct canxl_frame)) #define CANXL_HDR_SIZE (offsetof(struct canxl_frame, data)) #define CANXL_MIN_MTU (CANXL_HDR_SIZE + 64) #define CANXL_MAX_MTU CANXL_MTU /* particular protocols of the protocol family PF_CAN */ #define CAN_RAW 1 /* RAW sockets */ #define CAN_BCM 2 /* Broadcast Manager */ #define CAN_TP16 3 /* VAG Transport Protocol v1.6 */ #define CAN_TP20 4 /* VAG Transport Protocol v2.0 */ #define CAN_MCNET 5 /* Bosch MCNet */ #define CAN_ISOTP 6 /* ISO 15765-2 Transport Protocol */ #define CAN_J1939 7 /* SAE J1939 */ #define CAN_NPROTO 8 #define SOL_CAN_BASE 100 /** * struct sockaddr_can - the sockaddr structure for CAN sockets * @can_family: address family number AF_CAN. * @can_ifindex: CAN network interface index. * @can_addr: protocol specific address information */ struct sockaddr_can { __kernel_sa_family_t can_family; int can_ifindex; union { /* transport protocol class address information (e.g. ISOTP) */ struct { canid_t rx_id, tx_id; } tp; /* J1939 address information */ struct { /* 8 byte name when using dynamic addressing */ __u64 name; /* pgn: * 8 bit: PS in PDU2 case, else 0 * 8 bit: PF * 1 bit: DP * 1 bit: reserved */ __u32 pgn; /* 1 byte address */ __u8 addr; } j1939; /* reserved for future CAN protocols address information */ } can_addr; }; /** * struct can_filter - CAN ID based filter in can_register(). * @can_id: relevant bits of CAN ID which are not masked out. * @can_mask: CAN mask (see description) * * Description: * A filter matches, when * * <received_can_id> & mask == can_id & mask * * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can * filter for error message frames (CAN_ERR_FLAG bit set in mask). */ struct can_filter { canid_t can_id; canid_t can_mask; }; #define CAN_INV_FILTER 0x20000000U /* to be set in can_filter.can_id */ #define CAN_RAW_FILTER_MAX 512 /* maximum number of can_filter set via setsockopt() */ #endif /* !_UAPI_CAN_H */