From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CAF1A2874E1; Tue, 14 Oct 2025 19:32:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760470323; cv=none; b=Bb9Gem+JfzLUBNXv+j/KIiAjcfcdrVYlKVpt+31a5kQ0Pvm/tzazKt6J9qPcCblAecnrVESIdtmfEBTvMs9zUxNLeZdX0w4aM/K5tK1zBanYf5SQrw/kXhhLnwMc86es+fuCXkq+9FdE2RvpIOqYIST6xGmZakGOPILlXmsc29M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760470323; c=relaxed/simple; bh=X1XYILS4PYawHLwWQb6dY8gYVnKbbRtl5rUw+yvMvcI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=F2jy0NVycREoSJj18ctD9iTv4DfzgloQDS4vZrejQYntQyD96ibNG26fVGbS9hAix7ijWaFIKbzNReRJWyaTHeEpR1VAkNPWI4vjV+LTqA828Spf5w+p07LrEEo2zD2IVvyGr9pIbxKfKbOKN7Jg224l2W0USlSbl68DM7cOcOE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LCpA/e8I; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LCpA/e8I" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 28A10C4CEF9; Tue, 14 Oct 2025 19:32:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1760470323; bh=X1XYILS4PYawHLwWQb6dY8gYVnKbbRtl5rUw+yvMvcI=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=LCpA/e8IfQcXZrCtmPpmkDVgugz9ns/LpbYH29kpFdma3eTBZv54uz0ZJ27lqYJ0k vsygBYRg662v9jVwelASkkkmK5IGr654MM1qA2PssDmldzmK0LHbS9qdIKxTh/FLQI 3dbxGzu8gxCMtp0RSBMfkPXIIwF5MU2LsgLJKi5n6sFbDyXM6NlP2wSuUa5dMl98mU UruIk32ihN6/krwwOGYV6CLDbzMyE03J9CDnZT1Lu3uMvALMOpIW9DIgT4pwkpEEmZ ZF1fjcnnoKOt+Q4GyuC9E5XaVu1mmu1k2U4xj4ckcsaaryvPytfw15NpVpn0BPIhVo A3M6ds98zRC2A== Message-ID: Date: Tue, 14 Oct 2025 13:32:02 -0600 Precedence: bulk X-Mailing-List: linux-mmc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] mmc: pxamci: Simplify pxamci_probe() error handling using devm APIs To: Rakuram Eswaran , ulf.hansson@linaro.org Cc: u.kleine-koenig@baylibre.com, chenhuacai@kernel.org, david.hunter.linux@gmail.com, skhan@linuxfoundation.org, zhoubinbin@loongson.cn, linux-kernel-mentees@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mmc@vger.kernel.org, kernel test robot , Dan Carpenter References: <20251014184657.111144-1-rakuram.e96@gmail.com> Content-Language: en-US From: Khalid Aziz In-Reply-To: <20251014184657.111144-1-rakuram.e96@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 10/14/25 12:46 PM, Rakuram Eswaran wrote: > This patch refactors pxamci_probe() to use devm-managed resource > allocation (e.g. devm_dma_request_chan()) and dev_err_probe() for > improved readability and automatic cleanup on probe failure. > > This eliminates redundant NULL assignments and manual release logic. > > This issue was originally reported by Smatch: > drivers/mmc/host/pxamci.c:709 pxamci_probe() warn: passing zero to 'PTR_ERR' > > The warning occurred because a pointer was set to NULL before using > PTR_ERR(), leading to PTR_ERR(0) and an incorrect 0 return value. > This refactor eliminates that condition while improving overall > error handling robustness. > > Reported-by: kernel test robot > Reported-by: Dan Carpenter > Closes: https://lore.kernel.org/r/202510041841.pRlunIfl-lkp@intel.com/ > Fixes: 58c40f3faf742c ("mmc: pxamci: Use devm_mmc_alloc_host() helper") > Suggested-by: Uwe Kleine-König > Signed-off-by: Rakuram Eswaran > --- > > Changes since v1: > Following Uwe Kleine-König’s suggestion: > - Replaced dma_request_chan() with devm_dma_request_chan() to make DMA > channel allocation devm-managed and avoid manual release paths. > - Used dev_err_probe() for improved error reporting and consistent > probe failure handling. > - Removed redundant NULL assignments and obsolete goto-based cleanup logic. > - Updated commit message to better describe the intent of the change. > > Testing note: > I do not have access to appropriate hardware for runtime testing. > Any help verifying on actual hardware would be appreciated. > > Build and Analysis: > This patch was compiled against the configuration file reported by > 0day CI in the above link (config: s390-randconfig-r071-20251004) using > `s390x-linux-gnu-gcc (Ubuntu 14.2.0-19ubuntu2) 14.2.0`. > > Static analysis was performed with Smatch to ensure the reported warning > no longer reproduces after applying this fix. > > Command used for verification: > ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- \ > ~/project/smatch/smatch_scripts/kchecker ./drivers/mmc/host/pxamci.c > > drivers/mmc/host/pxamci.c | 57 +++++++++++++++------------------------ > 1 file changed, 21 insertions(+), 36 deletions(-) > > diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c > index 26d03352af63..d03388f64934 100644 > --- a/drivers/mmc/host/pxamci.c > +++ b/drivers/mmc/host/pxamci.c > @@ -652,11 +652,14 @@ static int pxamci_probe(struct platform_device *pdev) > host->clkrt = CLKRT_OFF; > > host->clk = devm_clk_get(dev, NULL); > - if (IS_ERR(host->clk)) { > - host->clk = NULL; > - return PTR_ERR(host->clk); > - } > + if (IS_ERR(host->clk)) > + return dev_err_probe(dev, PTR_ERR(host->clk), > + "Failed to acquire clock\n"); > > + /* > + * Note that the return value of clk_get_rate() is only valid > + * if the clock is enabled. > + */ > host->clkrate = clk_get_rate(host->clk); > > /* > @@ -703,46 +706,36 @@ static int pxamci_probe(struct platform_device *pdev) > > platform_set_drvdata(pdev, mmc); > > - host->dma_chan_rx = dma_request_chan(dev, "rx"); > - if (IS_ERR(host->dma_chan_rx)) { > - host->dma_chan_rx = NULL; > + host->dma_chan_rx = devm_dma_request_chan(dev, "rx"); > + if (IS_ERR(host->dma_chan_rx)) > return dev_err_probe(dev, PTR_ERR(host->dma_chan_rx), > "unable to request rx dma channel\n"); > - } > > - host->dma_chan_tx = dma_request_chan(dev, "tx"); > - if (IS_ERR(host->dma_chan_tx)) { > - dev_err(dev, "unable to request tx dma channel\n"); > - ret = PTR_ERR(host->dma_chan_tx); > - host->dma_chan_tx = NULL; > - goto out; > - } > + host->dma_chan_tx = devm_dma_request_chan(dev, "tx"); > + if (IS_ERR(host->dma_chan_tx)) > + return dev_err_probe(dev, PTR_ERR(host->dma_chan_tx), > + "unable to request tx dma channel\n"); > > if (host->pdata) { > host->detect_delay_ms = host->pdata->detect_delay_ms; > > host->power = devm_gpiod_get_optional(dev, "power", GPIOD_OUT_LOW); > - if (IS_ERR(host->power)) { > - ret = PTR_ERR(host->power); > - dev_err(dev, "Failed requesting gpio_power\n"); > - goto out; > - } > + if (IS_ERR(host->power)) > + return dev_err_probe(dev, PTR_ERR(host->power), > + "Failed requesting gpio_power\n"); > > /* FIXME: should we pass detection delay to debounce? */ > ret = mmc_gpiod_request_cd(mmc, "cd", 0, false, 0); > - if (ret && ret != -ENOENT) { > - dev_err(dev, "Failed requesting gpio_cd\n"); > - goto out; > - } > + if (ret && ret != -ENOENT) > + return dev_err_probe(dev, ret, "Failed requesting gpio_cd\n"); > > if (!host->pdata->gpio_card_ro_invert) > mmc->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH; > > ret = mmc_gpiod_request_ro(mmc, "wp", 0, 0); > - if (ret && ret != -ENOENT) { > - dev_err(dev, "Failed requesting gpio_ro\n"); > - goto out; > - } > + if (ret && ret != -ENOENT) > + return dev_err_probe(dev, ret, "Failed requesting gpio_ro\n"); > + > if (!ret) > host->use_ro_gpio = true; > > @@ -759,16 +752,8 @@ static int pxamci_probe(struct platform_device *pdev) > if (ret) { > if (host->pdata && host->pdata->exit) > host->pdata->exit(dev, mmc); > - goto out; > } > > - return 0; > - > -out: > - if (host->dma_chan_rx) > - dma_release_channel(host->dma_chan_rx); > - if (host->dma_chan_tx) > - dma_release_channel(host->dma_chan_tx); > return ret; > } > This looks good now. Reviewed-by: Khalid Aziz -- Khalid