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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 BA153C433E0 for ; Tue, 19 May 2020 11:17:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8F7C8207D3 for ; Tue, 19 May 2020 11:17:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728686AbgESLRv (ORCPT ); Tue, 19 May 2020 07:17:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54990 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728573AbgESLRv (ORCPT ); Tue, 19 May 2020 07:17:51 -0400 Received: from omr1.cc.vt.edu (omr1.cc.ipv6.vt.edu [IPv6:2607:b400:92:8300:0:c6:2117:b0e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1659CC05BD09 for ; Tue, 19 May 2020 04:17:51 -0700 (PDT) Received: from mr6.cc.vt.edu (mr6.cc.vt.edu [IPv6:2607:b400:92:8500:0:af:2d00:4488]) by omr1.cc.vt.edu (8.14.4/8.14.4) with ESMTP id 04JBHnXp031223 for ; Tue, 19 May 2020 07:17:49 -0400 Received: from mail-qt1-f200.google.com (mail-qt1-f200.google.com [209.85.160.200]) by mr6.cc.vt.edu (8.14.7/8.14.7) with ESMTP id 04JBHiwg021978 for ; Tue, 19 May 2020 07:17:49 -0400 Received: by mail-qt1-f200.google.com with SMTP id n33so16315322qtd.10 for ; Tue, 19 May 2020 04:17:49 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:in-reply-to:references :mime-version:content-transfer-encoding:date:message-id; bh=XdezUHtnjEPl34SNV/OG/wiZxI5dHtj/gxxjDGommaM=; b=BGHqIySBQWJkRoZ5RVOp+Ab2FtVmQe5OJ+gM5QLWeRvMwna/V7nwD2ivCsaBjLnYmw 9vvc1fRLhI5m5ZmE8zLa3LsY3xq1fpeVqAeDd47MqVoRyQnD/AdN6YdH0iPjBReDMugx SAM6YqOmvC9MHDHn6Jh4QFlHrKN4ldVxdzOFh0OF7BigsuTO9dfhw5S8aUnObsZrAUcB 6zd3w5KgMEYgX/WxC1iBFB1tUFzUFGn+EBxpAiVzxkDY5E/+tSBs7MCLu1fw63iI0k3s Tp6AS5pmlZqUClk0yatPeB3MeVk5KR+TNutW6+PPStZIywIYogGphdH87q+720rXiSmc nPeQ== X-Gm-Message-State: AOAM532OzbbC2tEhbgc5Zdl11ddhaimzs+LPTrpWmNIXMhKqPeJo+eOH aj7ZcSB9jfWynW9JOiyf2DuzqNPhUa6MLrbb+gY3RUGufOYsCJmzrogByGvE5rrpMzpj9x6pAkU 9Zf5Ix1R0/wOvRwTBw1IZkuwTYlv8v2w= X-Received: by 2002:a0c:aec5:: with SMTP id n5mr20903692qvd.0.1589887064023; Tue, 19 May 2020 04:17:44 -0700 (PDT) X-Google-Smtp-Source: ABdhPJzYm/oMeyoCURXB8A/ux+JFjkbZhUA+4db9QUZHAWEUR8WA0qRoukom4Qn9ITWbQR/8QthsHQ== X-Received: by 2002:a0c:aec5:: with SMTP id n5mr20903663qvd.0.1589887063744; Tue, 19 May 2020 04:17:43 -0700 (PDT) Received: from turing-police ([2601:5c0:c001:c9e1::359]) by smtp.gmail.com with ESMTPSA id z65sm10191073qkc.91.2020.05.19.04.17.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 19 May 2020 04:17:42 -0700 (PDT) From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Google-Original-From: "Valdis Kl=?utf-8?Q?=c4=93?=tnieks" X-Mailer: exmh version 2.9.0 11/07/2018 with nmh-1.7+dev To: Qii Wang Cc: Joe Perches , Geert Uytterhoeven , Wolfram Sang , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , srv_heupstream@mediatek.com, leilk.liu@mediatek.com, "Linux Kernel Mailing List" , linux-mediatek@lists.infradead.org, Linux I2C , Linux ARM Subject: Re: [PATCH v2 2/2] i2c: mediatek: Add i2c ac-timing adjust support In-Reply-To: <1589857073.25512.34.camel@mhfsdcap03> References: <1589461844-15614-1-git-send-email-qii.wang@mediatek.com> <1589461844-15614-3-git-send-email-qii.wang@mediatek.com> <1589857073.25512.34.camel@mhfsdcap03> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1589887060_31675P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Tue, 19 May 2020 07:17:41 -0400 Message-ID: <116825.1589887061@turing-police> Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org --==_Exmh_1589887060_31675P Content-Type: text/plain; charset=us-ascii On Tue, 19 May 2020 10:57:53 +0800, Qii Wang said: > (1000000000 * (sample_cnt + 1)) / clk_src value is a 32-bit, (1000000000 > * (sample_cnt + 1)) will over 32-bit if sample_cnt is 7. > > I think 1000000000 and clk_src is too big, maybe I can reduce then with > be divided all by 1000. Yes, it's definitely too big, the 3 DIV_ROUND_UP calls in mtk_i2c_check_ac_timing() end up causing a build issue during modpost on a 32-bit RPi4: ERROR: modpost: "__aeabi_uldivmod" [drivers/i2c/busses/i2c-mt65xx.ko] undefined! ERROR: modpost: "__aeabi_ldivmod" [drivers/i2c/busses/i2c-mt65xx.ko] undefined! --==_Exmh_1589887060_31675P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Comment: Exmh version 2.9.0 11/07/2018 iQIVAwUBXsPAVAdmEQWDXROgAQLPGg/9GGQpzw7XKYxr/tvBAg5sc8H1rTqhNMQF FGBWDl46QaKwfWatNNq0L6HGC2X9FDlG7hdzIi0HJFJjTDVGlN9C/QNH5zeCmMCF zDcbsj8tnLoNMW4v2Dl3Q2ZxFWihnepXqfzg8KG5fDDiEHSaP38hDe8GK/MXb5X/ KjGRXMF1qQnbDh2q1trjaJExQqbJ2D2wyngaUS0vDqJOaXm3TaY91NbNUQUVlOmd wQl05fDL7ziCbcrxn5HdNSxaBiSTNtQwcBrsV8JF7YImeyDx+/I974qRSxZB8zKF +RPabakMPOZFBgHrikYKplTogjXN5fCCF8F/muITK1/EPpI9PgeMDZNCGU07xRux v8/UkqwLqAuAnqG3vm5F9I1q+0qbEyyCaU4Mm2DWMGyYzCHXAkfQAJQF/MkQhE54 JxyZKSv7Y4x+nMgL4tlD37DFGCVTXlk9nUyKcNqr08nlu2nDiszlTScHtuHnSqEo uk3mbh7mKYwpbMJIa/j0n5zLVabSB09IDZ5Jk/+ZlTPh143zTqqFXKfB5akC6Ve5 6pGPcsXJl6ubOdaLT8LcxRVkyaKa/3tYXLBFjxsu6NkfNhytddnVzPAw6/5qRcos M4R7h0mvQLLRPDLrTkNq1ur6V/3xgup/M8qAunQyKWPNZXYPvNc93Vgh1b6274o0 aL8PqtTCnss= =SvGK -----END PGP SIGNATURE----- --==_Exmh_1589887060_31675P--