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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 BCBE5C43142 for ; Mon, 28 Dec 2020 15:52:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A54C422573 for ; Mon, 28 Dec 2020 15:52:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391440AbgL1Ni2 (ORCPT ); Mon, 28 Dec 2020 08:38:28 -0500 Received: from mail-ot1-f45.google.com ([209.85.210.45]:41122 "EHLO mail-ot1-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391398AbgL1NiY (ORCPT ); Mon, 28 Dec 2020 08:38:24 -0500 Received: by mail-ot1-f45.google.com with SMTP id x13so9112743oto.8; Mon, 28 Dec 2020 05:38:08 -0800 (PST) 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; bh=xtrfQuQnyNAaVJXZ6+NykLzyM/gg5DoautEkBZLloKQ=; b=XreerNaYqzFmQZcZkkQyCPSpOKhwTjjo2xWiG9wTC5UhMnt7GYcRWv4yVub9THkl1m xq3n0n8P6G2iz72uGcvKP5uNv1GsECOnKDuddcz43bTjwr7q2D9sFtGqd6KF/vTp0jLz acuonjG2AvmJhHwbtSVqkoskwD/hhnfl/grnsXlu4Um12IheBAzljsSdTyV6y8bAz1bO /tcZZE1N4L+cCKMj6ZEanceyaVUJmNeJSUBSStKraZbeDtqsenyZ9GJ9OyVuwq7W7gE4 7PpCku9ve4pwCZxsbescCT32THHDpka4bMmHe/0JGjhSB+buWHNbnzEEeYVU9hT7mMB/ erkw== X-Gm-Message-State: AOAM530hx+FGM/MKyQRfHiWYaiXm/bs2xqMzEqbLRBkrzJnkAhUWQv+P g1J9/jXQZlBngIrdLDqaCcEJ3bFfmlpIlh3mQAg6nHjF X-Google-Smtp-Source: ABdhPJwRKFKOGwrhQo6MkWu7nf73xZXEdW3xtWzT5PYhCCTBANFRv9cSRZQAD0yFMLygz7+JhGEPOm80gLjWa1fA3w0= X-Received: by 2002:a05:6830:210a:: with SMTP id i10mr32898563otc.145.1609162662989; Mon, 28 Dec 2020 05:37:42 -0800 (PST) MIME-Version: 1.0 References: <20201223172154.34462-1-wsa+renesas@sang-engineering.com> <20201223172154.34462-5-wsa+renesas@sang-engineering.com> In-Reply-To: <20201223172154.34462-5-wsa+renesas@sang-engineering.com> From: Geert Uytterhoeven Date: Mon, 28 Dec 2020 14:37:32 +0100 Message-ID: Subject: Re: [PATCH 4/4] i2c: rcar: protect against supurious interrupts on V3U To: Wolfram Sang Cc: Linux I2C , Linux-Renesas , Kuninori Morimoto , Yoshihiro Shimoda Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Hi Wolfram, On Wed, Dec 23, 2020 at 6:24 PM Wolfram Sang wrote: > V3U creates spurious interrupts which we need to handle. This costs time > until BUS_PHASE_DATA can be activated which is problematic for Gen2 SoCs > and earlier. Because of this we introduce two interrupt handlers here > which will call a generic main irq function once the timing critical > stuff is done. > > Signed-off-by: Wolfram Sang Thanks for your patch! > --- a/drivers/i2c/busses/i2c-rcar.c > +++ b/drivers/i2c/busses/i2c-rcar.c > @@ -625,20 +625,11 @@ static bool rcar_i2c_slave_irq(struct rcar_i2c_priv *priv) > * generated. It turned out that taking a spinlock at the beginning of the ISR > * was already causing repeated messages. Thus, this driver was converted to > * the now lockless behaviour. Please keep this in mind when hacking the driver. > + * R-Car Gen3 seems to have this fixed but earlier versions than R-Car Gen2 are s/than/like/? > + * likely affected. Therefore, we have different interrupt handler entries. > */ Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds