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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 34739CCA473 for ; Fri, 3 Jun 2022 15:57:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343540AbiFCP5S (ORCPT ); Fri, 3 Jun 2022 11:57:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59728 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343509AbiFCP5Q (ORCPT ); Fri, 3 Jun 2022 11:57:16 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B47F64DF; Fri, 3 Jun 2022 08:57:15 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 275F6B82376; Fri, 3 Jun 2022 15:57:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E519C385A9; Fri, 3 Jun 2022 15:57:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1654271832; bh=HoAH8VUSJkTU91dOsuHMUpmGc42O1/PdsZRIM1Rg2LM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Ibh+E3eXNswhfW0vlgaHdmD7Hj1o8MVbv/7ztFjLNsWTxRqu4l6DCdN7+DdxN7EOf k4inn4zBbmxDKeTDVZfk7Pm0PXNaLlqphv474X53BPZhzQfpr6+busQS9A/0ECkdcB cDfLLUUIeF6GlLDqCWWsAEsg+S9TJCG/4lp+ar+c3j+z/0XU9ktWHrixwMzrNykUZi 9xEB5Oc79xZ0w/6wxyPa4sIiH/ULTUKSmgdKgUGrTE5obhbERL91UvzdQ/s9x6mPbM ePqVVc0lMwqvEKUlNnQbuTO9+CxmybY1UDoSUiEM0v/auy9UPzNlbCYPJNRVg72J1l Yf3jVEapZk8EA== Date: Fri, 3 Jun 2022 17:06:12 +0100 From: Jonathan Cameron To: Andy Shevchenko Cc: linux-iio@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-amlogic@lists.infradead.org, linux-kernel@vger.kernel.org, Lars-Peter Clausen , Neil Armstrong , Kevin Hilman , Jerome Brunet , Martin Blumenstingl Subject: Re: [PATCH v3 1/6] iio: adc: meson_saradc: Don't attach managed resource to IIO device object Message-ID: <20220603170612.561edfbf@jic23-huawei> In-Reply-To: <20220603100004.70336-1-andriy.shevchenko@linux.intel.com> References: <20220603100004.70336-1-andriy.shevchenko@linux.intel.com> X-Mailer: Claws Mail 4.1.0 (GTK 3.24.34; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 3 Jun 2022 12:59:59 +0300 Andy Shevchenko wrote: > It feels wrong and actually inconsistent to attach managed resources > to the IIO device object, which is child of the physical device object. > The rest of the ->probe() calls do that against physical device. > > Resolve this by reassigning managed resources to the physical device object. > > Fixes: 3adbf3427330 ("iio: adc: add a driver for the SAR ADC found in Amlogic Meson SoCs") > Suggested-by: Lars-Peter Clausen > Signed-off-by: Andy Shevchenko Hi Andy, This has come up a few times in the past (and we elected to not clean it up at the time, though it wasn't a decision to never do so!) It would definitely be wrong if we had another driver binding against the resulting created device (funnily enough I reported a bug on a driver doing just that earlier this week), but in this case it's harmless because the the tear down will occur with a put_device() ultimately calling device_release() and devres_release_all() https://elixir.bootlin.com/linux/latest/source/drivers/base/core.c#L2211 Has a comment that covers this case (more or less). " * Some platform devices are driven without driver attached * and managed resources may have been acquired. Make sure * all resources are released. " Now, I definitely agree with your statement that it's a bit inconsistent to do this, just not the fixes tag. One other suggestion below. > --- > v3: new fix-patch > drivers/iio/adc/meson_saradc.c | 12 +++++------- > 1 file changed, 5 insertions(+), 7 deletions(-) > > diff --git a/drivers/iio/adc/meson_saradc.c b/drivers/iio/adc/meson_saradc.c > index 62cc6fb0ef85..4fe6b997cd03 100644 > --- a/drivers/iio/adc/meson_saradc.c > +++ b/drivers/iio/adc/meson_saradc.c > @@ -650,11 +650,11 @@ static int meson_sar_adc_clk_init(struct iio_dev *indio_dev, > void __iomem *base) > { > struct meson_sar_adc_priv *priv = iio_priv(indio_dev); > + struct device *dev = indio_dev->dev.parent; I'd slightly prefer the device was passed in explicitly to this function rather than using the parent assignment which feels a little fragile. > struct clk_init_data init; > const char *clk_parents[1]; > > - init.name = devm_kasprintf(&indio_dev->dev, GFP_KERNEL, "%s#adc_div", > - dev_name(indio_dev->dev.parent)); > + init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_div", dev_name(dev)); > if (!init.name) > return -ENOMEM; > > @@ -670,13 +670,11 @@ static int meson_sar_adc_clk_init(struct iio_dev *indio_dev, > priv->clk_div.hw.init = &init; > priv->clk_div.flags = 0; > > - priv->adc_div_clk = devm_clk_register(&indio_dev->dev, > - &priv->clk_div.hw); > + priv->adc_div_clk = devm_clk_register(dev, &priv->clk_div.hw); > if (WARN_ON(IS_ERR(priv->adc_div_clk))) > return PTR_ERR(priv->adc_div_clk); > > - init.name = devm_kasprintf(&indio_dev->dev, GFP_KERNEL, "%s#adc_en", > - dev_name(indio_dev->dev.parent)); > + init.name = devm_kasprintf(dev, GFP_KERNEL, "%s#adc_en", dev_name(dev)); > if (!init.name) > return -ENOMEM; > > @@ -690,7 +688,7 @@ static int meson_sar_adc_clk_init(struct iio_dev *indio_dev, > priv->clk_gate.bit_idx = __ffs(MESON_SAR_ADC_REG3_CLK_EN); > priv->clk_gate.hw.init = &init; > > - priv->adc_clk = devm_clk_register(&indio_dev->dev, &priv->clk_gate.hw); > + priv->adc_clk = devm_clk_register(dev, &priv->clk_gate.hw); > if (WARN_ON(IS_ERR(priv->adc_clk))) > return PTR_ERR(priv->adc_clk); >