From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D4A9C433ED for ; Tue, 4 May 2021 10:26:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DE14561040 for ; Tue, 4 May 2021 10:26:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230316AbhEDK1J convert rfc822-to-8bit (ORCPT ); Tue, 4 May 2021 06:27:09 -0400 Received: from relay-b03.edpnet.be ([212.71.1.220]:60692 "EHLO relay-b03.edpnet.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230328AbhEDK1I (ORCPT ); Tue, 4 May 2021 06:27:08 -0400 X-ASG-Debug-ID: 1620123027-15c43553ead31ab0001-ZXuqFv Received: from zotac.vandijck-laurijssen.be (94.105.122.62.dyn.edpnet.net [94.105.122.62]) by relay-b03.edpnet.be with ESMTP id ZZAlTdfcBncX78KZ; Tue, 04 May 2021 12:10:27 +0200 (CEST) X-Barracuda-Envelope-From: dev.kurt@vandijck-laurijssen.be X-Barracuda-Effective-Source-IP: 94.105.122.62.dyn.edpnet.net[94.105.122.62] X-Barracuda-Apparent-Source-IP: 94.105.122.62 Received: from x1.vandijck-laurijssen.be (x1.vandijck-laurijssen.be [IPv6:fd01::1a1d:eaff:fe02:d339]) by zotac.vandijck-laurijssen.be (Postfix) with ESMTPSA id 59DA213B59CB; Tue, 4 May 2021 12:10:27 +0200 (CEST) Date: Tue, 4 May 2021 12:10:26 +0200 From: Kurt Van Dijck To: Marc Kleine-Budde Cc: Ayoub Kaanich , Vincent MAILHOL , linux-can Subject: Re: More flags for logging Message-ID: <20210504101026.GC27660@x1.vandijck-laurijssen.be> X-ASG-Orig-Subj: Re: More flags for logging Mail-Followup-To: Marc Kleine-Budde , Ayoub Kaanich , Vincent MAILHOL , linux-can References: <20210503100246.n7uu437kbabdzu7m@pengutronix.de> <20210503100810.cacbmdfmpjipgoka@pengutronix.de> <20210503154749.q3nrfjveixsqp3uj@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8BIT In-Reply-To: <20210503154749.q3nrfjveixsqp3uj@pengutronix.de> User-Agent: Mutt/1.5.22 (2013-10-16) X-Barracuda-Connect: 94.105.122.62.dyn.edpnet.net[94.105.122.62] X-Barracuda-Start-Time: 1620123027 X-Barracuda-URL: https://212.71.1.220:443/cgi-mod/mark.cgi X-Virus-Scanned: by bsmtpd at edpnet.be X-Barracuda-Scan-Msg-Size: 873 X-Barracuda-BRTS-Status: 1 X-Barracuda-Spam-Score: 0.00 X-Barracuda-Spam-Status: No, SCORE=0.00 using global scores of TAG_LEVEL=1000.0 QUARANTINE_LEVEL=1000.0 KILL_LEVEL=7.0 tests= X-Barracuda-Spam-Report: Code version 3.2, rules version 3.2.3.89703 Rule breakdown below pts rule name description ---- ---------------------- -------------------------------------------------- Precedence: bulk List-ID: X-Mailing-List: linux-can@vger.kernel.org On Mon, 03 May 2021 17:47:49 +0200, Marc Kleine-Budde wrote: > On 03.05.2021 15:31:34, Ayoub Kaanich wrote: > > For the ack bit, I think we could go with the bit being a “NO_ACK” > > bit, so a spy listener will set it to 1, if it receives a CAN frame, > > but it does not see any node in the bus acknowledging it. This way we > > preserve backward compatibility. > > As Vincent pointed out, the device should not receive the CAN frame that > has not been acked as I do on the flexcan. > > And even on the mcp251xfd, where I receive the CAN frame, there's no way > to tell if this frame has been acked or not. in listen-only mode, it's debatable if you should see an ack. If there's only 1 active node on the bus, you would not be able to probe the bitrate using listen-only mode, unless you accept CAN frames that are only miss the ACK bit. Kurt