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=-7.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 C82D3C282DE for ; Wed, 5 Jun 2019 07:23:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9D8DD2075C for ; Wed, 5 Jun 2019 07:23:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="LxIaZty5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726556AbfFEHXN (ORCPT ); Wed, 5 Jun 2019 03:23:13 -0400 Received: from mail-io1-f66.google.com ([209.85.166.66]:44387 "EHLO mail-io1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726551AbfFEHXM (ORCPT ); Wed, 5 Jun 2019 03:23:12 -0400 Received: by mail-io1-f66.google.com with SMTP id s7so12083573iob.11 for ; Wed, 05 Jun 2019 00:23:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=bFlickOGyCE8q2nid47CTokWI0/Tlpvfgy/2BgVqxGM=; b=LxIaZty5SFUHpeOd6VDojbonDevwkb/pcxQ1fTAr8bq2nAGRG0FUXbB1ahd4Cs8yIg oRPSkndInGzFgEmm/7b8+X+6UoxWShv3j+IC09/3LLXcEjsZyFDlSftzMZGeWVKdukuX tRxKQheHKNttUpTHH5/RMjZ+9n5MZjzcjavgM2hp/GDi8kasXudamsoB8q5ZYKcvvRFK oXRYVu3aAEZpJ3wnVIPhImAJzexpje8nEOn7PZhmrjPhy8orFBxeeLwbH0l94g5oP+Bm HWPA8NJ/LOwXgcprZGF5/kFXdsM8GDFUlEgPx3qrwshAgepVR88j0fhlf2GCzx85nK3B zqWw== 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=bFlickOGyCE8q2nid47CTokWI0/Tlpvfgy/2BgVqxGM=; b=IWsrcWCUj3dRa8doi12tpBXD6ndDzPs7cp+iH6yEIoTKWt0rJkedRb9RT0jJAaAdVH ZF2F0M0IWlQ4PZ6cVMtrFsy4Hs4ct4x128+a1F8VyMxOeyMUb+0JzlKuktDkqRXciVNS vVzUQT46MuhsJ8fkXhtLDyj5wrAoonFAqHOTW8FlbcVJyeDoYc/UKdQ/Xasoivqlh6o9 xk4WJJ1QSvyeyaV1qejjyDL+VAUJ7dmGoigzYPLJr17sjYlHnVsyosTwUhH6M/yuw6T2 xV52/3y50SVhmO0HIrb+s8JW/Jtl9DyetoNL3vqxrHZ/lupS2fk+T8bj4aCa/mpl93b+ HkLg== X-Gm-Message-State: APjAAAVlYrr8wLgSdBowbQZvdxxxDMIV45PBrAcsLZlkNJOpaxA1mQ6E LBuPoPPBwYub9yDHlPmo674GP15Cd643TtOWttD4gA== X-Google-Smtp-Source: APXvYqyvUHNyNwg2/0w1ihfOoePLCRKJbrn5Y6sShasQnJXGkrj6UQ0uvq3+cXzOG4W7XlqhT4twEcbHEF/T3XAEymE= X-Received: by 2002:a5d:9402:: with SMTP id v2mr7086874ion.128.1559719391862; Wed, 05 Jun 2019 00:23:11 -0700 (PDT) MIME-Version: 1.0 References: <20190604104455.8877-1-lee.jones@linaro.org> <20190604104455.8877-2-lee.jones@linaro.org> <20190605062020.GL22737@tuxbook-pro> <20190605071625.GK4797@dell> In-Reply-To: <20190605071625.GK4797@dell> From: Ard Biesheuvel Date: Wed, 5 Jun 2019 09:22:59 +0200 Message-ID: Subject: Re: [PATCH 2/8] i2c: i2c-qcom-geni: Signify successful driver probe To: Lee Jones Cc: Bjorn Andersson , balbi@kernel.org, wsa+renesas@sang-engineering.com, Greg Kroah-Hartman , Linus Walleij , linux-usb , Linux Kernel Mailing List , David Brown , alokc@codeaurora.org, kramasub@codeaurora.org, linux-i2c , "open list:GPIO SUBSYSTEM" , linux-arm-msm , Andy Gross , Jeffrey Hugo , linux-arm-kernel Content-Type: text/plain; charset="UTF-8" Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Wed, 5 Jun 2019 at 09:16, Lee Jones wrote: > > On Tue, 04 Jun 2019, Bjorn Andersson wrote: > > > On Tue 04 Jun 03:44 PDT 2019, Lee Jones wrote: > > > > > The Qualcomm Geni I2C driver currently probes silently which can be > > > confusing when debugging potential issues. Add a low level (INFO) > > > print when each I2C controller is successfully initially set-up. > > > > > > Signed-off-by: Lee Jones > > > --- > > > drivers/i2c/busses/i2c-qcom-geni.c | 2 ++ > > > 1 file changed, 2 insertions(+) > > > > > > diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c > > > index 0fa93b448e8d..e27466d77767 100644 > > > --- a/drivers/i2c/busses/i2c-qcom-geni.c > > > +++ b/drivers/i2c/busses/i2c-qcom-geni.c > > > @@ -598,6 +598,8 @@ static int geni_i2c_probe(struct platform_device *pdev) > > > return ret; > > > } > > > > > > + dev_info(&pdev->dev, "Geni-I2C adaptor successfully added\n"); > > > + > > > > I would prefer that we do not add such prints, as it would be to accept > > the downstream behaviour of spamming the log to the point where no one > > will ever look through it. > > We should be able to find a middle ground. Spamming the log with all > sorts of device specific information/debug is obviously not > constructive, but a single liner to advertise that an important > device/controller has been successfully initialised is more helpful > than it is hinderous. > > This print was added due to the silent initialisation costing me > several hours of debugging ACPI device/driver code (albeit learning a > lot about ACPI as I go) just to find out that it was already doing the > right thing - just very quietly. > I agree. There are numerous EHCI drivers IIRC which, if compiled in, unconditionally print some blurb, whether you have the hardware or not, which is pretty annoying. In this case, however, having a single line per successfully probed device (containing the dev_name and perhaps the MMIO base address or some other identifying feature) is pretty useful, and shouldn't be regarded as log spamming imo. dev_info() honours the 'quiet' kernel command line parameter, and so you will only see the message if you actually look at the log.