/* 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 */
#endif /* !_UAPI_CAN_H */
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