From mboxrd@z Thu Jan 1 00:00:00 1970 X-GM-THRID: 6138556841984 X-Google-Groups: outreachy-kernel X-Google-Thread: 9ca63f596c,db883bf8dd7e9dae X-Google-Attributes: gid9ca63f596c,domainid0,private,googlegroup X-Google-NewGroupId: yes X-Received: by 10.152.28.137 with SMTP id b9mr4605723lah.8.1425392862928; Tue, 03 Mar 2015 06:27:42 -0800 (PST) X-BeenThere: outreachy-kernel@googlegroups.com Received: by 10.180.8.193 with SMTP id t1ls774959wia.30.canary; Tue, 03 Mar 2015 06:27:42 -0800 (PST) X-Received: by 10.180.13.195 with SMTP id j3mr3019422wic.2.1425392862569; Tue, 03 Mar 2015 06:27:42 -0800 (PST) Return-Path: Received: from mail-wg0-x230.google.com (mail-wg0-x230.google.com. [2a00:1450:400c:c00::230]) by gmr-mx.google.com with ESMTPS id by11si931576wib.1.2015.03.03.06.27.42 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 03 Mar 2015 06:27:42 -0800 (PST) Received-SPF: pass (google.com: domain of mahfouz.saif.elyazal@gmail.com designates 2a00:1450:400c:c00::230 as permitted sender) client-ip=2a00:1450:400c:c00::230; Authentication-Results: gmr-mx.google.com; spf=pass (google.com: domain of mahfouz.saif.elyazal@gmail.com designates 2a00:1450:400c:c00::230 as permitted sender) smtp.mail=mahfouz.saif.elyazal@gmail.com; dkim=pass header.i=@gmail.com; dmarc=pass (p=NONE dis=NONE) header.from=gmail.com Received: by mail-wg0-x230.google.com with SMTP id l18so40334649wgh.8 for ; Tue, 03 Mar 2015 06:27:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=date:from:to:subject:message-id:mime-version:content-type :content-disposition:user-agent; bh=4Wf/YPU8w2fdEsWJfmpX3fcK4J2HBiA1NJKxl0r2zEc=; b=qrqO8J8VEpY71hRBHQdIgq9kYrUH4zvfrB1ryMw3qOgqzP8Mbp1Nj3qWDjClnUF2tI 7IuV0RLU7UAc3OWpBunSsfa+FlZtj8BHk/1TXSbhKdFepaPajdb9LrdXoSfV2pZw2use Ku5GXIm0sIy+FXEwDcqqYdUEtZrnNn0yEtU5f5LCy9t59K0l18F+QjfzzzpVIHXvEB/O 6eFhw4w3pfwSGS1pettd861U6adLx7gDvzUGe9+TcaTstjhaejBxoKLiGD/0WrmInQL7 5L286NCMAYYRVcbU0k1cP3zBIsxgUT0ovQUh2lkS8WYLOEMkp4Gj+TPBsETYhBvm73GT ztRQ== X-Received: by 10.180.81.7 with SMTP id v7mr3342437wix.27.1425392862457; Tue, 03 Mar 2015 06:27:42 -0800 (PST) Return-Path: Received: from localhost.localdomain ([196.205.191.99]) by mx.google.com with ESMTPSA id w4sm2682294wib.19.2015.03.03.06.27.40 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 03 Mar 2015 06:27:41 -0800 (PST) Date: Tue, 3 Mar 2015 16:27:37 +0200 From: Aya Mahfouz To: outreachy-kernel@googlegroups.com Subject: [PATCH v5] staging: iio: meter: add check on return variables Message-ID: <20150303142737.GA27100@waves> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) adds checks on variables that are used to return values. If the value is less than zero, this indicates that an error occurred and hence a message is printed through dev_err. Checks are made on negative values only since spi_* functions return negative error codes. The functions were found using the following script but the aforementioned modification was what was carried out in the end: @@ identifier len,f; @@ -int len; ... when != len when strict -len = +return f(...); -return len; Signed-off-by: Aya Mahfouz --- v1: added checks on last calls only. v2: added checks on all calls that return values along with labels. v3: added changelog that was missed in v2. v4: adjusted the patch to state how the problem was discovered, simplify the if conditions and avoid redundant error messages. v5: added driver specific error messages drivers/staging/iio/meter/ade7758_core.c | 30 ++++++++++++++++-------------- 1 file changed, 16 insertions(+), 14 deletions(-) diff --git a/drivers/staging/iio/meter/ade7758_core.c b/drivers/staging/iio/meter/ade7758_core.c index 70e96b2..7e287da 100644 --- a/drivers/staging/iio/meter/ade7758_core.c +++ b/drivers/staging/iio/meter/ade7758_core.c @@ -303,14 +303,15 @@ static int ade7758_reset(struct device *dev) int ret; u8 val; - ade7758_spi_read_reg_8(dev, - ADE7758_OPMODE, - &val); + ret = ade7758_spi_read_reg_8(dev, ADE7758_OPMODE, &val); + if (ret < 0) { + dev_err(dev, "Failed to read opmode reg\n"); + return ret; + } val |= 1 << 6; /* Software Chip Reset */ - ret = ade7758_spi_write_reg_8(dev, - ADE7758_OPMODE, - val); - + ret = ade7758_spi_write_reg_8(dev, ADE7758_OPMODE, val); + if (ret < 0) + dev_err(dev, "Failed to write opmode reg\n"); return ret; } @@ -444,14 +445,15 @@ static int ade7758_stop_device(struct device *dev) int ret; u8 val; - ade7758_spi_read_reg_8(dev, - ADE7758_OPMODE, - &val); + ret = ade7758_spi_read_reg_8(dev, ADE7758_OPMODE, &val); + if (ret < 0) { + dev_err(dev, "Failed to read opmode reg\n"); + return ret; + } val |= 7 << 3; /* ADE7758 powered down */ - ret = ade7758_spi_write_reg_8(dev, - ADE7758_OPMODE, - val); - + ret = ade7758_spi_write_reg_8(dev, ADE7758_OPMODE, val); + if (ret < 0) + dev_err(dev, "Failed to write opmode reg\n"); return ret; } -- 1.9.3 -- Kind Regards, Aya Saif El-yazal Mahfouz