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  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 3. Neither the name of Volkswagen nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * Alternatively, provided that this notice is retained in full, this
  24  * software may be distributed under the terms of the GNU General
  25  * Public License ("GPL") version 2, in which case the provisions of the
  26  * GPL apply INSTEAD OF those given above.
  27  *
  28  * The provided data structures and external interfaces from this code
  29  * are not restricted to be used by modules with a GPL compatible license.
  30  *
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  36  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  37  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  38  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  39  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  40  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  41  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  42  * DAMAGE.
  43  */
  44
  45 #ifndef CAN_H
  46 #define CAN_H
  47
  48 #include <linux/types.h>
  49 #include <linux/socket.h>
  50
  51 /* controller area network (CAN) kernel definitions */
  52
  53 /* special address description flags for the CAN_ID */
  54 #define CAN_EFF_FLAG 0x80000000U /* EFF/SFF is set in the MSB */
  55 #define CAN_RTR_FLAG 0x40000000U /* remote transmission request */
  56 #define CAN_ERR_FLAG 0x20000000U /* error message frame */
  57
  58 /* valid bits in CAN ID for frame formats */
  59 #define CAN_SFF_MASK 0x000007FFU /* standard frame format (SFF) */
  60 #define CAN_EFF_MASK 0x1FFFFFFFU /* extended frame format (EFF) */
  61 #define CAN_ERR_MASK 0x1FFFFFFFU /* omit EFF, RTR, ERR flags */
  62
  63 /*
  64  * Controller Area Network Identifier structure
  65  *
  66  * bit 0-28     : CAN identifier (11/29 bit)
  67  * bit 29       : error message frame flag (0 = data frame, 1 = error message)
  68  * bit 30       : remote transmission request flag (1 = rtr frame)
  69  * bit 31       : frame format flag (0 = standard 11 bit, 1 = extended 29 bit)
  70  */
  71 typedef __u32 canid_t;
  72
  73 #define CAN_SFF_ID_BITS         11
  74 #define CAN_EFF_ID_BITS         29
  75
  76 /*
  77  * Controller Area Network Error Message Frame Mask structure
  78  *
  79  * bit 0-28     : error class mask (see include/linux/can/error.h)
  80  * bit 29-31    : set to zero
  81  */
  82 typedef __u32 can_err_mask_t;
  83
  84 /* CAN payload length and DLC definitions according to ISO 11898-1 */
  85 #define CAN_MAX_DLC 8
  86 #define CAN_MAX_DLEN 8
  87
  88 /* CAN FD payload length and DLC definitions according to ISO 11898-7 */
  89 #define CANFD_MAX_DLC 15
  90 #define CANFD_MAX_DLEN 64
  91
  92 /**
  93  * struct can_frame - basic CAN frame structure
  94  * @can_id:  CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition
  95  * @can_dlc: frame payload length in byte (0 .. 8) aka data length code
  96  *           N.B. the DLC field from ISO 11898-1 Chapter 8.4.2.3 has a 1:1
  97  *           mapping of the 'data length code' to the real payload length
  98  * @data:    CAN frame payload (up to 8 byte)
  99  */
 100 struct can_frame {
 101         canid_t can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */
 102         __u8    can_dlc; /* frame payload length in byte (0 .. CAN_MAX_DLEN) */
 103         __u8    data[CAN_MAX_DLEN] __attribute__((aligned(8)));
 104 };
 105
 106 /*
 107  * defined bits for canfd_frame.flags
 108  *
 109  * The use of struct canfd_frame implies the Extended Data Length (EDL) bit to
 110  * be set in the CAN frame bitstream on the wire. The EDL bit switch turns
 111  * the CAN controllers bitstream processor into the CAN FD mode which creates
 112  * two new options within the CAN FD frame specification:
 113  *
 114  * Bit Rate Switch - to indicate a second bitrate is/was used for the payload
 115  * Error State Indicator - represents the error state of the transmitting node
 116  *
 117  * As the CANFD_ESI bit is internally generated by the transmitting CAN
 118  * controller only the CANFD_BRS bit is relevant for real CAN controllers when
 119  * building a CAN FD frame for transmission. Setting the CANFD_ESI bit can make
 120  * sense for virtual CAN interfaces to test applications with echoed frames.
 121  */
 122 #define CANFD_BRS 0x01 /* bit rate switch (second bitrate for payload data) */
 123 #define CANFD_ESI 0x02 /* error state indicator of the transmitting node */
 124
 125 /**
 126  * struct canfd_frame - CAN flexible data rate frame structure
 127  * @can_id: CAN ID of the frame and CAN_*_FLAG flags, see canid_t definition
 128  * @len:    frame payload length in byte (0 .. CANFD_MAX_DLEN)
 129  * @flags:  additional flags for CAN FD
 130  * @__res0: reserved / padding
 131  * @__res1: reserved / padding
 132  * @data:   CAN FD frame payload (up to CANFD_MAX_DLEN byte)
 133  */
 134 struct canfd_frame {
 135         canid_t can_id;  /* 32 bit CAN_ID + EFF/RTR/ERR flags */
 136         __u8    len;     /* frame payload length in byte */
 137         __u8    flags;   /* additional flags for CAN FD */
 138         __u8    __res0;  /* reserved / padding */
 139         __u8    __res1;  /* reserved / padding */
 140         __u8    data[CANFD_MAX_DLEN] __attribute__((aligned(8)));
 141 };
 142
 143 #define CAN_MTU         (sizeof(struct can_frame))
 144 #define CANFD_MTU       (sizeof(struct canfd_frame))
 145
 146 /* particular protocols of the protocol family PF_CAN */
 147 #define CAN_RAW         1 /* RAW sockets */
 148 #define CAN_BCM         2 /* Broadcast Manager */
 149 #define CAN_TP16        3 /* VAG Transport Protocol v1.6 */
 150 #define CAN_TP20        4 /* VAG Transport Protocol v2.0 */
 151 #define CAN_MCNET       5 /* Bosch MCNet */
 152 #define CAN_ISOTP       6 /* ISO 15765-2 Transport Protocol */
 153 #define CAN_NPROTO      7
 154
 155 #define SOL_CAN_BASE 100
 156
 157 /**
 158  * struct sockaddr_can - the sockaddr structure for CAN sockets
 159  * @can_family:  address family number AF_CAN.
 160  * @can_ifindex: CAN network interface index.
 161  * @can_addr:    protocol specific address information
 162  */
 163 struct sockaddr_can {
 164         __kernel_sa_family_t can_family;
 165         int         can_ifindex;
 166         union {
 167                 /* transport protocol class address information (e.g. ISOTP) */
 168                 struct { canid_t rx_id, tx_id; } tp;
 169
 170                 /* reserved for future CAN protocols address information */
 171         } can_addr;
 172 };
 173
 174 /**
 175  * struct can_filter - CAN ID based filter in can_register().
 176  * @can_id:   relevant bits of CAN ID which are not masked out.
 177  * @can_mask: CAN mask (see description)
 178  *
 179  * Description:
 180  * A filter matches, when
 181  *
 182  *          <received_can_id> & mask == can_id & mask
 183  *
 184  * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can
 185  * filter for error message frames (CAN_ERR_FLAG bit set in mask).
 186  */
 187 struct can_filter {
 188         canid_t can_id;
 189         canid_t can_mask;
 190 };
 191
 192 #define CAN_INV_FILTER 0x20000000U /* to be set in can_filter.can_id */
 193
 194 #endif /* CAN_H */