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 DA61F3DFC75; Thu, 19 Mar 2026 15:12:00 +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=1773933121; cv=none; b=tSFEGscnb45+KXN4uFpqPOxJEs9b/Y8yjJjRZUY84D02OkqHaupjkZC7WloM0TpS2XnwnmKXzyY2A/gi2zYSXKURtPYIDpR+A0iaEtsp5yEv7+T4VZE5IR+rmYBd6l5ESXXFS9Le6YZMqrdfvz125TTHPRNZIL7Vwn+woFie3gY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773933121; c=relaxed/simple; bh=UX9bnwd/iOEELMYCow66V4EiBuo/TPrF6n7M8pxHr58=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=YdOPSbzrVc9HUVraqalEIN6LJ68nJpNsIuOils1tZ6RFCTYRDm380Up2vhelOMZNkrO0UCmlPS2I/rCrkQ52vSdbRwrdJ/bM+XAUvHaWXjvuK7RUNrP0S1s/P4uVF7cC9uPeI1J4zhfDqGpK030YD3cG1eE0RDU73NWNL2AK6uw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jIJM84bW; 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="jIJM84bW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2C9CBC19424; Thu, 19 Mar 2026 15:11:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773933120; bh=UX9bnwd/iOEELMYCow66V4EiBuo/TPrF6n7M8pxHr58=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=jIJM84bW79Px6PgBLe3udUr0KpystcPIgPvi3YneDh6SYID/OimOMS9WGfsz4k/f6 rzqU56knhxoL8U+7INgxmgMQbUezs+2nPzVcUsoW0l3pK3gPqNeNJlx4OxA0lrrjGI NEBT6Y7vhetQYaZjFrtp+GgknzZI+SFw7kQHfSz1K9QZW3A0Mac9vKGQ8SMkCmQZkL rFi6jlvgJ9yGXL/YSN5gkIY9lDIw4uVl931vN8xWWpgeokREUvUBJEmPVJZIP/Q8S3 VnBHEzA4eLhaKkhsTGkT6Ekerjyq8aPK1AlV7g1fAaYkQBeoQP9szSzG4z7aeI75lg SHfVLblJI91+Q== Date: Thu, 19 Mar 2026 15:11:54 +0000 From: Lee Jones To: Bjorn Andersson Cc: Srinivas Kandagatla , Pierre-Louis Bossart , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mfd: wcd934x: Unroll regmap and irqchip on removal Message-ID: <20260319151154.GM554736@google.com> References: <20260309-wcd934x-unroll-regmap-v1-1-9a5fb305540e@oss.qualcomm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260309-wcd934x-unroll-regmap-v1-1-9a5fb305540e@oss.qualcomm.com> On Mon, 09 Mar 2026, Bjorn Andersson wrote: > When the slimbus-up event is handled a new regmap is created, an IRQ > chip is registered on this regmap and then the MFD devices are added. > > But the regmap is left dangling if either any of those operations are > failing or if the slimbus-down event ever comes. Which manifest itself > as an error print from debugfs once the next slimbus-up event happens. > > Likewise, if for some reason a slimbus-down event would be followed by > a slimbus-up event without the MFD being torn down by the slimbus > controller inbetween, we're going to have a dangling irq_chip. > > Add cleanup of the registered resources on failure and on removal. > > Fixes: 6ac7e4d7ad70 ("mfd: wcd934x: Add support to wcd9340/wcd9341 codec") > Signed-off-by: Bjorn Andersson > --- > drivers/mfd/wcd934x.c | 49 ++++++++++++++++++++++++++++++++++++++----------- > 1 file changed, 38 insertions(+), 11 deletions(-) > > diff --git a/drivers/mfd/wcd934x.c b/drivers/mfd/wcd934x.c > index 3c3080e8c8cf7ecaaa62e255c7e01a850e65e9ad..b03cc91cc3a6a114a34efdb278420ae3dfa016eb 100644 > --- a/drivers/mfd/wcd934x.c > +++ b/drivers/mfd/wcd934x.c > @@ -170,29 +170,56 @@ static int wcd934x_slim_status_up(struct slim_device *sdev) > ret = wcd934x_bring_up(ddata); > if (ret) { > dev_err(dev, "Failed to bring up WCD934X: err = %d\n", ret); > - return ret; > + goto err_regmap_exit; > } > > - ret = devm_regmap_add_irq_chip(dev, ddata->regmap, ddata->irq, > - IRQF_TRIGGER_HIGH, 0, > - &wcd934x_regmap_irq_chip, > - &ddata->irq_data); > + ret = regmap_add_irq_chip(ddata->regmap, ddata->irq, > + IRQF_TRIGGER_HIGH, 0, > + &wcd934x_regmap_irq_chip, > + &ddata->irq_data); > if (ret) { > dev_err(dev, "Failed to add IRQ chip: err = %d\n", ret); > - return ret; > + goto err_regmap_exit; > } > > ret = mfd_add_devices(dev, PLATFORM_DEVID_AUTO, wcd934x_devices, > ARRAY_SIZE(wcd934x_devices), NULL, 0, NULL); > if (ret) { > - dev_err(dev, "Failed to add child devices: err = %d\n", > - ret); > - return ret; > + dev_err(dev, "Failed to add child devices: err = %d\n", ret); > + goto err_del_irq_chip; > } > > + return 0; > + > +err_del_irq_chip: > + regmap_del_irq_chip(ddata->irq, ddata->irq_data); > + ddata->irq_data = NULL; > +err_regmap_exit: > + regmap_exit(ddata->regmap); > + ddata->regmap = NULL; > return ret; > } > > +static void wcd934x_slim_status_down(struct slim_device *sdev) > +{ > + struct device *dev = &sdev->dev; > + struct wcd934x_ddata *ddata; > + > + ddata = dev_get_drvdata(dev); Is this guaranteed to be populated? If this fails for any reason, we'll nul-ptr-deref below. > + mfd_remove_devices(&sdev->dev); > + > + if (ddata->irq_data) { > + regmap_del_irq_chip(ddata->irq, ddata->irq_data); > + ddata->irq_data = NULL; > + } > + > + if (ddata->regmap) { > + regmap_exit(ddata->regmap); > + ddata->regmap = NULL; > + } > +} [...] -- Lee Jones [李琼斯]