From d6e640f9766e2fb9aa3853b4ff19e4d7d5d7e373 Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Tue, 8 May 2012 22:20:33 +0200 Subject: can: update documentation wording error frames -> error messages As Heinz-Juergen Oertel pointed out 'CAN error frames' are a already defined term for the CAN protocol violation indication on the wire. To avoid confusion with the error messages created by CAN drivers available via CAN RAW sockets update the documentation and change the naming from 'error frames' to 'error messages' or 'error message frames'. Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- include/linux/can.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'include/linux/can.h') diff --git a/include/linux/can.h b/include/linux/can.h index 9a19bcb3eeaf..17334c09bd93 100644 --- a/include/linux/can.h +++ b/include/linux/can.h @@ -21,7 +21,7 @@ /* 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 frame */ +#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) */ @@ -32,14 +32,14 @@ * Controller Area Network Identifier structure * * bit 0-28 : CAN identifier (11/29 bit) - * bit 29 : error frame flag (0 = data frame, 1 = error frame) + * 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; /* - * Controller Area Network Error Frame Mask structure + * 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 @@ -97,7 +97,7 @@ struct sockaddr_can { * & mask == can_id & mask * * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can - * filter for error frames (CAN_ERR_FLAG bit set in mask). + * filter for error message frames (CAN_ERR_FLAG bit set in mask). */ struct can_filter { canid_t can_id; -- cgit From 7c9416365c60f150ef8961a2855fafbc7394ad6b Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Wed, 13 Jun 2012 20:04:33 +0200 Subject: canfd: add new data structures and constants - add new struct canfd_frame - check identical element offsets in struct can_frame and struct canfd_frame - new ETH_P_CANFD definition to tag CAN FD skbs correctly - add CAN_MTU and CANFD_MTU definitions for easy frame and mode detection - add CAN[FD]_MAX_[DLC|DLEN] helper constants to remove hard coded values - update existing struct can_frame with helper constants and comments Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- include/linux/can.h | 59 ++++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 54 insertions(+), 5 deletions(-) (limited to 'include/linux/can.h') diff --git a/include/linux/can.h b/include/linux/can.h index 17334c09bd93..1a66cf6112ae 100644 --- a/include/linux/can.h +++ b/include/linux/can.h @@ -46,18 +46,67 @@ typedef __u32 canid_t; */ 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: the CAN ID of the frame and CAN_*_FLAG flags, see above. - * @can_dlc: the data length field of the CAN frame - * @data: the CAN frame payload. + * @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; /* data length code: 0 .. 8 */ - __u8 data[8] __attribute__((aligned(8))); + __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 + * + * As the default for CAN FD should be to support the high data rate in the + * payload section of the frame (HDR) and to support up to 64 byte in the + * data section (EDL) the bits are only set in the non-default case. + * Btw. as long as there's no real implementation for CAN FD network driver + * these bits are only preliminary. + * + * RX: NOHDR/NOEDL - info about received CAN FD frame + * ESI - bit from originating CAN controller + * TX: NOHDR/NOEDL - control per-frame settings if supported by CAN controller + * ESI - bit is set by local CAN controller + */ +#define CANFD_NOHDR 0x01 /* frame without high data rate */ +#define CANFD_NOEDL 0x02 /* frame without extended data length */ +#define CANFD_ESI 0x04 /* error state indicator */ + +/** + * 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 */ -- cgit From f057bbb6f9ed0fb61ea11105c9ef0ed5ac1a354d Mon Sep 17 00:00:00 2001 From: Rostislav Lisovy Date: Wed, 4 Jul 2012 05:32:03 +0200 Subject: net: em_canid: Ematch rule to match CAN frames according to their identifiers This ematch makes it possible to classify CAN frames (AF_CAN) according to their identifiers. This functionality can not be easily achieved with existing classifiers, such as u32, because CAN identifier is always stored in native endianness, whereas u32 expects Network byte order. Signed-off-by: Rostislav Lisovy Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde --- include/linux/can.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/can.h') diff --git a/include/linux/can.h b/include/linux/can.h index 1a66cf6112ae..018055efc034 100644 --- a/include/linux/can.h +++ b/include/linux/can.h @@ -38,6 +38,9 @@ */ typedef __u32 canid_t; +#define CAN_SFF_ID_BITS 11 +#define CAN_EFF_ID_BITS 29 + /* * Controller Area Network Error Message Frame Mask structure * -- cgit