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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 19A66C4338F for ; Mon, 16 Aug 2021 10:41:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E9EB861BC1 for ; Mon, 16 Aug 2021 10:41:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231979AbhHPKlg convert rfc822-to-8bit (ORCPT ); Mon, 16 Aug 2021 06:41:36 -0400 Received: from mail-lj1-f173.google.com ([209.85.208.173]:39558 "EHLO mail-lj1-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230124AbhHPKlf (ORCPT ); Mon, 16 Aug 2021 06:41:35 -0400 Received: by mail-lj1-f173.google.com with SMTP id q21so4892779ljj.6; Mon, 16 Aug 2021 03:41:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=UAgKx9qFimpGqmGeQ3TM0J7Mzn3ZTYhunGpWKj3QW8E=; b=nyexwiSYDeAsM5rhwe390lHcZXxDORt6nUPfzaISmvlk41DyuGEucvb57xenctilfZ +iA02oMlVdWexn0FT3XK+IzBN157tuC0BE0hyeQadaq7rtYDpz1xszCrIZnb8mZAf909 rj/sPDK6J9OAxnHEiWb8bh9dz0XCmgDFV19bWeu7hKU96aLLSP0qKJTz8nbK4e+NZgRw iSlqAgeISYZ6PA10HzkZw2XI+6ZLYxfzkDgtCXlwEWtJ2wBl4+tI3RrokeW38iBGD3TJ YDlR8hv5JDVwnQmqaFcB42oj5Qi1rIKqJBfAMXGFcP3m2HcfYe4UgAAgsJDYLAK+n7hc faCQ== X-Gm-Message-State: AOAM530Y4xMGAieU3C90nfSMdRQyJ7Ku/OaEZvzfctD8+kfwE+AuJNdd /h5gctffoptOR966ig/t/1lfAxkKnpWbCrVkHLs= X-Google-Smtp-Source: ABdhPJxsH8x3EfCOw+pbE7D3sXGxvSvKLrPv+OSgf3ha/r/wegNx+Ubs6UxpEeEqHJoV3c7h3WC3ycTLGRw8+iUhr8g= X-Received: by 2002:a05:651c:24a:: with SMTP id x10mr10915127ljn.60.1629110463281; Mon, 16 Aug 2021 03:41:03 -0700 (PDT) MIME-Version: 1.0 References: <20210814101728.75334-1-mailhol.vincent@wanadoo.fr> <20210814101728.75334-5-mailhol.vincent@wanadoo.fr> <20210816081205.7rjdskaui35f3jml@pengutronix.de> In-Reply-To: <20210816081205.7rjdskaui35f3jml@pengutronix.de> From: Vincent MAILHOL Date: Mon, 16 Aug 2021 19:40:52 +0900 Message-ID: Subject: Re: [PATCH v5 4/4] iplink_can: add new CAN FD bittiming parameters: Transmitter Delay Compensation (TDC) To: Marc Kleine-Budde Cc: Stephen Hemminger , linux-can , =?UTF-8?Q?Stefan_M=C3=A4tje?= , netdev , open list Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-can@vger.kernel.org On Mon. 16 août 2021 at 17:12, Marc Kleine-Budde wrote: > On 14.08.2021 19:17:28, Vincent Mailhol wrote: > > At high bit rates, the propagation delay from the TX pin to the RX pin > > of the transceiver causes measurement errors: the sample point on the > > RX pin might occur on the previous bit. > > > > This issue is addressed in ISO 11898-1 section 11.3.3 "Transmitter > > delay compensation" (TDC). > > > > This patch brings command line support to nine TDC parameters which > > were recently added to the kernel's CAN netlink interface in order to > > implement TDC: > > - IFLA_CAN_TDC_TDCV_MIN: Transmitter Delay Compensation Value > > minimum value > > - IFLA_CAN_TDC_TDCV_MAX: Transmitter Delay Compensation Value > > maximum value > > - IFLA_CAN_TDC_TDCO_MIN: Transmitter Delay Compensation Offset > > minimum value > > - IFLA_CAN_TDC_TDCO_MAX: Transmitter Delay Compensation Offset > > maximum value > > - IFLA_CAN_TDC_TDCF_MIN: Transmitter Delay Compensation Filter > > window minimum value > > - IFLA_CAN_TDC_TDCF_MAX: Transmitter Delay Compensation Filter > > window maximum value > > - IFLA_CAN_TDC_TDCV: Transmitter Delay Compensation Value > > - IFLA_CAN_TDC_TDCO: Transmitter Delay Compensation Offset > > - IFLA_CAN_TDC_TDCF: Transmitter Delay Compensation Filter window > > > > All those new parameters are nested together into the attribute > > IFLA_CAN_TDC. > > > > A tdc-mode parameter allow to specify how to operate. Valid options > > are: > > > > * auto: the transmitter automatically measures TDCV. As such, TDCV > > values can not be manually provided. In this mode, the user must > > specify TDCO and may also specify TDCF if supported. > > > > * manual: Use the TDCV value provided by the user are used. In this > ^^^^^ ^^^ > singular plural ACK. I fixed that broken grammar in my local branch. As commented before, I will send the next version of the iproute series after we agree on the kernel part (unless someone finds a major issue). FYI, this is the fixed sentence: * manual: use a static TDCV provided by the user. In this mode, the user must specify both TDCV and TDCO and may also specify TDCF if supported. Yours sincerely, Vincent