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=unavailable 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 78B6EC433B4 for ; Wed, 14 Apr 2021 18:00:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5706E61168 for ; Wed, 14 Apr 2021 18:00:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351533AbhDNSAV (ORCPT ); Wed, 14 Apr 2021 14:00:21 -0400 Received: from mail-vs1-f53.google.com ([209.85.217.53]:37687 "EHLO mail-vs1-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234303AbhDNSAS (ORCPT ); Wed, 14 Apr 2021 14:00:18 -0400 Received: by mail-vs1-f53.google.com with SMTP id 2so10774755vsh.4; Wed, 14 Apr 2021 10:59:55 -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; bh=LrQhYoofWK1qIE+Puebb8490xY7FtwOJErFPSvGIMtY=; b=shBio9KXJcxBAmzKpdwcUWISMSsYL8M3tQO4z507KY7PgFMkaEswmzkin+rxfTFEUw gE4FBQTec8Moz+tuk7xwCZCQ694Dh34mYn1t3vrNYsTp6XtEo/yIyTOEObyybO6aZjIV +skifyO2nWsM3Z3ijX7gtDpYLtrtzg1JcaveBJzpODOGN1jTKKSRu1aEEGN4IlnfJbct HDplDg8Oc8YQmB06F4JvM8/oyHSW8KbX3UCwkBx7/t2JOamu5s6mlW8VE7omAkYl9bCY w1K2Og6Ug5L+vhdghyXYyoYkr0GknFN1TD18kRjMYxcz+FPdZERqV7nRsbZQvmly1iK3 7FQg== X-Gm-Message-State: AOAM531LqaKLI8iIRXD0m1UWr3iM/H2WaoPWUOy+C92HVyEXlTNx93N6 YjP0GApOe3SOjqCOX6O3o7/nOGUzO3Vp2eRPr8yBXqhjj/o= X-Google-Smtp-Source: ABdhPJyeOsV8TPzm4qfYRpIEOQxrAj6kXLid0sqN/BtkYP2cUAkLDMXrOtYnopbrTca5CncxrQqmj9wtMiDHf/+FZD8= X-Received: by 2002:a67:80c4:: with SMTP id b187mr29655934vsd.42.1618423195054; Wed, 14 Apr 2021 10:59:55 -0700 (PDT) MIME-Version: 1.0 References: <20210412132619.7896-1-aford173@gmail.com> <20210412132619.7896-2-aford173@gmail.com> In-Reply-To: From: Geert Uytterhoeven Date: Wed, 14 Apr 2021 19:59:43 +0200 Message-ID: Subject: Re: [PATCH V4 2/2] net: ethernet: ravb: Enable optional refclk To: Adam Ford Cc: netdev , Adam Ford-BE , Sergei Shtylyov , "David S. Miller" , Jakub Kicinski , Rob Herring , Linux-Renesas , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Adam, On Wed, Apr 14, 2021 at 3:08 PM Adam Ford wrote: > On Tue, Apr 13, 2021 at 2:33 AM Geert Uytterhoeven wrote: > > On Mon, Apr 12, 2021 at 3:27 PM Adam Ford wrote: > > > For devices that use a programmable clock for the AVB reference clock, > > > the driver may need to enable them. Add code to find the optional clock > > > and enable it when available. > > > > > > Signed-off-by: Adam Ford > > > Reviewed-by: Andrew Lunn > > > > > > --- > > > V4: Eliminate the NULL check when disabling refclk, and add a line > > > to disable the refclk if there is a failure after it's been > > > initialized. > > > > Thanks for the update! > > > > > --- a/drivers/net/ethernet/renesas/ravb_main.c > > > +++ b/drivers/net/ethernet/renesas/ravb_main.c > > > @@ -2148,6 +2148,13 @@ static int ravb_probe(struct platform_device *pdev) > > > goto out_release; > > > } > > > > > > + priv->refclk = devm_clk_get_optional(&pdev->dev, "refclk"); > > > + if (IS_ERR(priv->refclk)) { > > > + error = PTR_ERR(priv->refclk); > > > + goto out_release; > > > > Note that this will call clk_disable_unprepare() in case of failure, which is > > fine, as that function is a no-op in case of a failed clock. > > Geert, > > A bot reported that if I jump to out_release may try to free a clock > if some instances where priv isn't defined. As priv is allocated using alloc_etherdev_mqs(), priv->refclk is NULL initially, but priv itself may indeed not be initialized when the first "goto out_release" is taken. Sorry for missing that. > Currently, the priv->clk isn't freed either. I have heard some > back-and-forth discussions in other threads on whether or not devm > functions auto free or not. The devm_clk_get_optional() will be undone automatically, so there is no need to handle that explicitly. > I'm fine with sending a V5 to make the free for the refclock happen > only when the priv has successfully initialized. Should I also add As this patch has been applied to net-next, you''ll have to send a follow-up fix patch, not a v5. > one for freeing priv->clk and change all the other goto out_release > commands to point to this new section? No, not for priv->clk, due to devm_*(). > I am thinking it would like something like: > > free_refclk: > clk_disable_unprepare(priv->refclk); OK. > free_clk; > clk_disable_unprepare(priv->clk); NAK, as priv->clk is not enabled in ravb_probe(). > out_release: > free_netdev(ndev); > .... OK. Thanks! 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