From patchwork Fri Jun 10 08:45:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Nuno Sa X-Patchwork-Id: 12876871 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 6019ACCA485 for ; Fri, 10 Jun 2022 08:48:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348360AbiFJIs4 (ORCPT ); Fri, 10 Jun 2022 04:48:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48636 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348301AbiFJIsS (ORCPT ); Fri, 10 Jun 2022 04:48:18 -0400 Received: from mx0a-00128a01.pphosted.com (mx0a-00128a01.pphosted.com [148.163.135.77]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EA75162BE8; Fri, 10 Jun 2022 01:48:05 -0700 (PDT) Received: from pps.filterd (m0167089.ppops.net [127.0.0.1]) by mx0a-00128a01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 25A7noCd005281; Fri, 10 Jun 2022 04:48:05 -0400 Received: from nwd2mta4.analog.com ([137.71.173.58]) by mx0a-00128a01.pphosted.com (PPS) with ESMTPS id 3ghq33kq9b-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 10 Jun 2022 04:48:05 -0400 Received: from ASHBMBX8.ad.analog.com (ASHBMBX8.ad.analog.com [10.64.17.5]) by nwd2mta4.analog.com (8.14.7/8.14.7) with ESMTP id 25A8m4b4027550 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 10 Jun 2022 04:48:04 -0400 Received: from ASHBCASHYB5.ad.analog.com (10.64.17.133) by ASHBMBX8.ad.analog.com (10.64.17.5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.14; Fri, 10 Jun 2022 04:48:03 -0400 Received: from ASHBMBX9.ad.analog.com (10.64.17.10) by ASHBCASHYB5.ad.analog.com (10.64.17.133) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.14; Fri, 10 Jun 2022 04:48:03 -0400 Received: from zeus.spd.analog.com (10.66.68.11) by ashbmbx9.ad.analog.com (10.64.17.10) with Microsoft SMTP Server id 15.2.986.14 via Frontend Transport; Fri, 10 Jun 2022 04:48:00 -0400 Received: from nsa.ad.analog.com ([10.44.3.70]) by zeus.spd.analog.com (8.15.1/8.15.1) with ESMTP id 25A8imii014275; Fri, 10 Jun 2022 04:47:49 -0400 From: =?utf-8?q?Nuno_S=C3=A1?= To: , , , , , Lad Prabhakar , , , , , CC: Cai Huoqing , Benjamin Fair , Jishnu Prakash , "Linus Walleij" , Lars-Peter Clausen , Alexandre Torgue , Amit Kucheria , Andy Gross , Michael Hennerich , Haibo Chen , Benson Leung , "Rafael J. Wysocki" , "Alexandre Belloni" , Christophe Branchereau , Patrick Venture , Arnd Bergmann , Nancy Yuen , Sascha Hauer , Daniel Lezcano , "Gwendal Grignou" , Saravanan Sekar , "Tali Perry" , Maxime Coquelin , Paul Cercueil , Thara Gopinath , Avi Fishman , "Lorenzo Bianconi" , Claudiu Beznea , Pengutronix Kernel Team , Andy Shevchenko , Fabrice Gasnier , Matthias Brugger , Tomer Maimon , Bjorn Andersson , "Nicolas Ferre" , Jonathan Cameron , Zhang Rui , Shawn Guo , "Guenter Roeck" , Fabio Estevam , "Olivier Moysan" , Eugen Hristev , Miquel Raynal Subject: [PATCH 22/34] iio: inkern: only return error codes in iio_channel_get_*() APIs Date: Fri, 10 Jun 2022 10:45:33 +0200 Message-ID: <20220610084545.547700-23-nuno.sa@analog.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220610084545.547700-1-nuno.sa@analog.com> References: <20220610084545.547700-1-nuno.sa@analog.com> MIME-Version: 1.0 X-ADIRuleOP-NewSCL: Rule Triggered X-Proofpoint-ORIG-GUID: Y_iBkwY0TFr0zytvI3INOXjiF43q9YVc X-Proofpoint-GUID: Y_iBkwY0TFr0zytvI3INOXjiF43q9YVc X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.874,Hydra:6.0.517,FMLib:17.11.64.514 definitions=2022-06-10_02,2022-06-09_02,2022-02-23_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 mlxlogscore=842 phishscore=0 priorityscore=1501 adultscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 spamscore=0 impostorscore=0 bulkscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2204290000 definitions=main-2206100031 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org APIs like of_iio_channel_get_by_name() and of_iio_channel_get_all() were returning a mix of NULL and error pointers being NULL the way to "notify" that we should do a "system" lookup for channels. This make it very confusing and prone to errors as commit dbbccf7c20bf ("iio: inkern: fix return value in devm_of_iio_channel_get_by_name()") proves. On top of this, patterns like 'if (channel != NULL) return channel' were being used where channel could actually be an error code which makes the code hard to read. Signed-off-by: Nuno Sá --- drivers/iio/inkern.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c index 87fd2a0d44f2..31d9c122199a 100644 --- a/drivers/iio/inkern.c +++ b/drivers/iio/inkern.c @@ -214,7 +214,7 @@ static struct iio_channel *of_iio_channel_get(struct device_node *np, int index) struct iio_channel *of_iio_channel_get_by_name(struct device_node *np, const char *name) { - struct iio_channel *chan = NULL; + struct iio_channel *chan; /* Walk up the tree of devices looking for a matching iio channel */ while (np) { @@ -231,11 +231,11 @@ struct iio_channel *of_iio_channel_get_by_name(struct device_node *np, name); chan = of_iio_channel_get(np, index); if (!IS_ERR(chan) || PTR_ERR(chan) == -EPROBE_DEFER) - break; - else if (name && index >= 0) { + return chan; + if (name && index >= 0) { pr_err("ERROR: could not get IIO channel %pOF:%s(%i)\n", np, name ? name : "", index); - return NULL; + return chan; } /* @@ -245,10 +245,10 @@ struct iio_channel *of_iio_channel_get_by_name(struct device_node *np, */ np = np->parent; if (np && !of_get_property(np, "io-channel-ranges", NULL)) - return NULL; + return chan; } - return chan; + return ERR_PTR(-ENODEV); } EXPORT_SYMBOL_GPL(of_iio_channel_get_by_name); @@ -267,8 +267,8 @@ static struct iio_channel *of_iio_channel_get_all(struct device *dev) break; } while (++nummaps); - if (nummaps == 0) /* no error, return NULL to search map table */ - return NULL; + if (nummaps == 0) /* return -ENODEV to search map table */ + return ERR_PTR(-ENODEV); /* NULL terminated array to save passing size */ chans = kcalloc(nummaps + 1, sizeof(*chans), GFP_KERNEL); @@ -295,7 +295,7 @@ static struct iio_channel *of_iio_channel_get_all(struct device *dev) static inline struct iio_channel *of_iio_channel_get_all(struct device *dev) { - return NULL; + return ERR_PTR(-ENODEV); } #endif /* CONFIG_OF */ @@ -362,7 +362,7 @@ struct iio_channel *iio_channel_get(struct device *dev, if (dev) { channel = of_iio_channel_get_by_name(dev->of_node, channel_name); - if (channel != NULL) + if (!IS_ERR(channel) || PTR_ERR(channel) == -EPROBE_DEFER) return channel; } @@ -412,8 +412,6 @@ struct iio_channel *devm_of_iio_channel_get_by_name(struct device *dev, channel = of_iio_channel_get_by_name(np, channel_name); if (IS_ERR(channel)) return channel; - if (!channel) - return ERR_PTR(-ENODEV); ret = devm_add_action_or_reset(dev, devm_iio_channel_free, channel); if (ret) @@ -436,7 +434,7 @@ struct iio_channel *iio_channel_get_all(struct device *dev) return ERR_PTR(-EINVAL); chans = of_iio_channel_get_all(dev); - if (chans) + if (!IS_ERR(chans) || PTR_ERR(chans) == -EPROBE_DEFER) return chans; name = dev_name(dev);