Re: [PATCH] can: isotp: remove ISO 15675-2 specification version where possible

[Francesco Valla <valla.francesco@gmail.com>]

Hello,

just one small observation below. Other that that (FWIW):

Acked-by: Francesco Valla <valla.francesco@gmail.com>


On Sat, Apr 20, 2024 at 09:47:46PM +0200, Oliver Hartkopp wrote:
> With the new ISO 15765-2:2024 release the former documentation and comments
> have to be reworked. This patch removes the ISO specification version/date
> where possible.
> 
> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
> ---
>  include/uapi/linux/can/isotp.h |  2 +-
>  net/can/Kconfig                | 11 +++++------
>  net/can/isotp.c                | 11 ++++++-----
>  3 files changed, 12 insertions(+), 12 deletions(-)
> 
> diff --git a/include/uapi/linux/can/isotp.h b/include/uapi/linux/can/isotp.h
> index 6cde62371b6f..bd990917f7c4 100644
> --- a/include/uapi/linux/can/isotp.h
> +++ b/include/uapi/linux/can/isotp.h
> @@ -1,10 +1,10 @@
>  /* SPDX-License-Identifier: ((GPL-2.0-only WITH Linux-syscall-note) OR BSD-3-Clause) */
>  /*
>   * linux/can/isotp.h
>   *
> - * Definitions for isotp CAN sockets (ISO 15765-2:2016)
> + * Definitions for ISO 15765-2 CAN transport protocol sockets
>   *
>   * Copyright (c) 2020 Volkswagen Group Electronic Research
>   * All rights reserved.
>   *
>   * Redistribution and use in source and binary forms, with or without
> diff --git a/net/can/Kconfig b/net/can/Kconfig
> index cb56be8e3862..af64a6f76458 100644
> --- a/net/can/Kconfig
> +++ b/net/can/Kconfig
> @@ -54,20 +54,19 @@ config CAN_GW
>  	  by the netlink configuration interface known e.g. from iptables.
>  
>  source "net/can/j1939/Kconfig"
>  
>  config CAN_ISOTP
> -	tristate "ISO 15765-2:2016 CAN transport protocol"
> +	tristate "ISO 15765-2 CAN transport protocol"
>  	help
>  	  CAN Transport Protocols offer support for segmented Point-to-Point
>  	  communication between CAN nodes via two defined CAN Identifiers.
> +	  This protocol driver implements segmented data transfers for CAN CC
> +	  (aka Classical CAN, CAN 2.0B) and CAN FD frame types which were
> +	  introduced with ISO 15765-2:2016.

ISO 15765-2 also supports CAN2.0A networks, so I'd drop CAN 2.0B here.

>  	  As CAN frames can only transport a small amount of data bytes
> -	  (max. 8 bytes for 'classic' CAN and max. 64 bytes for CAN FD) this
> +	  (max. 8 bytes for CAN CC and max. 64 bytes for CAN FD) this
>  	  segmentation is needed to transport longer Protocol Data Units (PDU)
>  	  as needed e.g. for vehicle diagnosis (UDS, ISO 14229) or IP-over-CAN
>  	  traffic.
> -	  This protocol driver implements data transfers according to
> -	  ISO 15765-2:2016 for 'classic' CAN and CAN FD frame types.
> -	  If you want to perform automotive vehicle diagnostic services (UDS),
> -	  say 'y'.
>  
>  endif
> diff --git a/net/can/isotp.c b/net/can/isotp.c
> index 25bac0fafc83..16046931542a 100644
> --- a/net/can/isotp.c
> +++ b/net/can/isotp.c
> @@ -70,25 +70,26 @@
>  #include <linux/can/isotp.h>
>  #include <linux/slab.h>
>  #include <net/sock.h>
>  #include <net/net_namespace.h>
>  
> -MODULE_DESCRIPTION("PF_CAN isotp 15765-2:2016 protocol");
> +MODULE_DESCRIPTION("PF_CAN ISO 15765-2 transport protocol");
>  MODULE_LICENSE("Dual BSD/GPL");
>  MODULE_AUTHOR("Oliver Hartkopp <socketcan@hartkopp.net>");
>  MODULE_ALIAS("can-proto-6");
>  
>  #define ISOTP_MIN_NAMELEN CAN_REQUIRED_SIZE(struct sockaddr_can, can_addr.tp)
>  
>  #define SINGLE_MASK(id) (((id) & CAN_EFF_FLAG) ? \
>  			 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
>  			 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
>  
> -/* ISO 15765-2:2016 supports more than 4095 byte per ISO PDU as the FF_DL can
> - * take full 32 bit values (4 Gbyte). We would need some good concept to handle
> - * this between user space and kernel space. For now set the static buffer to
> - * something about 8 kbyte to be able to test this new functionality.
> +/* Since ISO 15765-2:2016 the CAN isotp protocol supports more than 4095
> + * byte per ISO PDU as the FF_DL can take full 32 bit values (4 Gbyte).
> + * We would need some good concept to handle this between user space and
> + * kernel space. For now set the static buffer to something about 8 kbyte
> + * to be able to test this new functionality.
>   */
>  #define DEFAULT_MAX_PDU_SIZE 8300
>  
>  /* maximum PDU size before ISO 15765-2:2016 extension was 4095 */
>  #define MAX_12BIT_PDU_SIZE 4095
> -- 
> 2.39.2
>