/* * linux/can.h * * Definitions for CAN network layer (socket addr / CAN frame / CAN filter) * * Authors: Oliver Hartkopp * Urs Thuermann * Copyright (c) 2002-2007 Volkswagen Group Electronic Research * All rights reserved. * */ #ifndef CAN_H #define CAN_H #include #include /* 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 */ /* * 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 /* * Controller Area Network Error Message Frame Mask structure * * bit 0-28 : error class mask (see include/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_DLEN 8 /* CAN FD payload length and DLC definitions according to ISO 11898-7 */ #define CANFD_MAX_DLC 15 #define CANFD_MAX_DLEN 64 /** * struct can_frame - basic CAN frame structure * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition * @can_dlc: frame payload length in byte (0 .. 8) aka data length code * N.B. the DLC field from ISO 11898-1 Chapter 8.4.2.3 has a 1:1 * mapping of the 'data length code' to the real payload length * @data: CAN frame payload (up to 8 byte) */ struct can_frame { canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */ __u8 can_dlc; /* frame payload length in byte (0 .. CAN_MAX_DLEN) */ __u8 data[CAN_MAX_DLEN] __attribute__((aligned(8))); }; /* * defined bits for canfd_frame.flags * * The use of struct canfd_frame implies the Extended Data Length (EDL) bit to * be set in the CAN frame bitstream on the wire. The EDL 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. */ #define CANFD_BRS 0x01 /* bit rate switch (second bitrate for payload data) */ #define CANFD_ESI 0x02 /* error state indicator of the transmitting node */ /** * 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))); }; #define CAN_MTU (sizeof(struct can_frame)) #define CANFD_MTU (sizeof(struct canfd_frame)) /* 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_NPROTO 7 #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; /* 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 * * & 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 */ #endif /* CAN_H */