include/uapi/linux/can.h

   1 /*
   2  * linux/can.h
   3  *
   4  * Definitions for CAN network layer (socket addr / CAN frame / CAN filter)
   5  *
   6  * Authors: Oliver Hartkopp <oliver.hartkopp@volkswagen.de>
   7  *          Urs Thuermann   <urs.thuermann@volkswagen.de>
   8  * Copyright (c) 2002-2007 Volkswagen Group Electronic Research
   9  * All rights reserved.
  10  *
  11  */
  12
  13 #ifndef CAN_H
  14 #define CAN_H
  15
  16 #include <linux/types.h>
  17 #include <linux/socket.h>
  18
  19 /* controller area network (CAN) kernel definitions */
  20
  21 /* special address description flags for the CAN_ID */
  22 #define CAN_EFF_FLAG 0x80000000U /* EFF/SFF is set in the MSB */
  23 #define CAN_RTR_FLAG 0x40000000U /* remote transmission request */
  24 #define CAN_ERR_FLAG 0x20000000U /* error message frame */
  25
  26 /* valid bits in CAN ID for frame formats */
  27 #define CAN_SFF_MASK 0x000007FFU /* standard frame format (SFF) */
  28 #define CAN_EFF_MASK 0x1FFFFFFFU /* extended frame format (EFF) */
  29 #define CAN_ERR_MASK 0x1FFFFFFFU /* omit EFF, RTR, ERR flags */
  30
  31 /*
  32  * Controller Area Network Identifier structure
  33  *
  34  * bit 0-28     : CAN identifier (11/29 bit)
  35  * bit 29       : error message frame flag (0 = data frame, 1 = error message)
  36  * bit 30       : remote transmission request flag (1 = rtr frame)
  37  * bit 31       : frame format flag (0 = standard 11 bit, 1 = extended 29 bit)
  38  */
  39 typedef __u32 canid_t;
  40
  41 #define CAN_SFF_ID_BITS         11
  42 #define CAN_EFF_ID_BITS         29
  43
  44 /*
  45  * Controller Area Network Error Message Frame Mask structure
  46  *
  47  * bit 0-28     : error class mask (see include/linux/can/error.h)
  48  * bit 29-31    : set to zero
  49  */
  50 typedef __u32 can_err_mask_t;
  51
  52 /* CAN payload length and DLC definitions according to ISO 11898-1 */
  53 #define CAN_MAX_DLC 8
  54 #define CAN_MAX_DLEN 8
  55
  56 /* CAN FD payload length and DLC definitions according to ISO 11898-7 */
  57 #define CANFD_MAX_DLC 15
  58 #define CANFD_MAX_DLEN 64
  59
  60 /**
  61  * struct can_frame - basic CAN frame structure
  62  * @can_id:  CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition
  63  * @can_dlc: frame payload length in byte (0 .. 8) aka data length code
  64  *           N.B. the DLC field from ISO 11898-1 Chapter 8.4.2.3 has a 1:1
  65  *           mapping of the 'data length code' to the real payload length
  66  * @data:    CAN frame payload (up to 8 byte)
  67  */
  68 struct can_frame {
  69         canid_t can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */
  70         __u8    can_dlc; /* frame payload length in byte (0 .. CAN_MAX_DLEN) */
  71         __u8    data[CAN_MAX_DLEN] __attribute__((aligned(8)));
  72 };
  73
  74 /*
  75  * defined bits for canfd_frame.flags
  76  *
  77  * The use of struct canfd_frame implies the Extended Data Length (EDL) bit to
  78  * be set in the CAN frame bitstream on the wire. The EDL bit switch turns
  79  * the CAN controllers bitstream processor into the CAN FD mode which creates
  80  * two new options within the CAN FD frame specification:
  81  *
  82  * Bit Rate Switch - to indicate a second bitrate is/was used for the payload
  83  * Error State Indicator - represents the error state of the transmitting node
  84  *
  85  * As the CANFD_ESI bit is internally generated by the transmitting CAN
  86  * controller only the CANFD_BRS bit is relevant for real CAN controllers when
  87  * building a CAN FD frame for transmission. Setting the CANFD_ESI bit can make
  88  * sense for virtual CAN interfaces to test applications with echoed frames.
  89  */
  90 #define CANFD_BRS 0x01 /* bit rate switch (second bitrate for payload data) */
  91 #define CANFD_ESI 0x02 /* error state indicator of the transmitting node */
  92
  93 /**
  94  * struct canfd_frame - CAN flexible data rate frame structure
  95  * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition
  96  * @len:    frame payload length in byte (0 .. CANFD_MAX_DLEN)
  97  * @flags:  additional flags for CAN FD
  98  * @__res0: reserved / padding
  99  * @__res1: reserved / padding
 100  * @data:   CAN FD frame payload (up to CANFD_MAX_DLEN byte)
 101  */
 102 struct canfd_frame {
 103         canid_t can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */
 104         __u8    len;     /* frame payload length in byte */
 105         __u8    flags;   /* additional flags for CAN FD */
 106         __u8    __res0;  /* reserved / padding */
 107         __u8    __res1;  /* reserved / padding */
 108         __u8    data[CANFD_MAX_DLEN] __attribute__((aligned(8)));
 109 };
 110
 111 #define CAN_MTU         (sizeof(struct can_frame))
 112 #define CANFD_MTU       (sizeof(struct canfd_frame))
 113
 114 /* particular protocols of the protocol family PF_CAN */
 115 #define CAN_RAW         1 /* RAW sockets */
 116 #define CAN_BCM         2 /* Broadcast Manager */
 117 #define CAN_TP16        3 /* VAG Transport Protocol v1.6 */
 118 #define CAN_TP20        4 /* VAG Transport Protocol v2.0 */
 119 #define CAN_MCNET       5 /* Bosch MCNet */
 120 #define CAN_ISOTP       6 /* ISO 15765-2 Transport Protocol */
 121 #define CAN_NPROTO      7
 122
 123 #define SOL_CAN_BASE 100
 124
 125 /**
 126  * struct sockaddr_can - the sockaddr structure for CAN sockets
 127  * @can_family:  address family number AF_CAN.
 128  * @can_ifindex: CAN network interface index.
 129  * @can_addr:    protocol specific address information
 130  */
 131 struct sockaddr_can {
 132         __kernel_sa_family_t can_family;
 133         int         can_ifindex;
 134         union {
 135                 /* transport protocol class address information (e.g. ISOTP) */
 136                 struct { canid_t rx_id, tx_id; } tp;
 137
 138                 /* reserved for future CAN protocols address information */
 139         } can_addr;
 140 };
 141
 142 /**
 143  * struct can_filter - CAN ID based filter in can_register().
 144  * @can_id:   relevant bits of CAN ID which are not masked out.
 145  * @can_mask: CAN mask (see description)
 146  *
 147  * Description:
 148  * A filter matches, when
 149  *
 150  *          <received_can_id> & mask == can_id & mask
 151  *
 152  * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
 153  * filter for error message frames (CAN_ERR_FLAG bit set in mask).
 154  */
 155 struct can_filter {
 156         canid_t can_id;
 157         canid_t can_mask;
 158 };
 159
 160 #define CAN_INV_FILTER 0x20000000U /* to be set in can_filter.can_id */
 161
 162 #endif /* CAN_H */