From patchwork Fri Aug 28 14:55:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tom Rix X-Patchwork-Id: 11743103 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DAD2014E5 for ; Fri, 28 Aug 2020 14:55:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C039520665 for ; Fri, 28 Aug 2020 14:55:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="H8shbgy2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727969AbgH1Ozc (ORCPT ); Fri, 28 Aug 2020 10:55:32 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:35027 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726400AbgH1Oz3 (ORCPT ); Fri, 28 Aug 2020 10:55:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1598626528; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc; bh=dY8soZQxplpIr5t025W/ct4MI2YimaV2y2Pnl5LKJQQ=; b=H8shbgy2sTHNy77hOkF+QYocEDyhHHzeIbE7Rm9BcrY5SwGMcSw4lJkADcrksjXm5l0m1e 7VFF6K156mjjZzaUKX3TX0UjUx0LLrVh+WCTZQs+xYr+ceOYe7hI/2J+6XRuOhd4fG4L0f F+xhYmVyvSDMCbECgMKnUlP+xDkhcd8= Received: from mail-qt1-f199.google.com (mail-qt1-f199.google.com [209.85.160.199]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-502-NksA_v27OJqjtQd1xS4D_g-1; Fri, 28 Aug 2020 10:55:25 -0400 X-MC-Unique: NksA_v27OJqjtQd1xS4D_g-1 Received: by mail-qt1-f199.google.com with SMTP id w1so900337qto.4 for ; Fri, 28 Aug 2020 07:55:25 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=dY8soZQxplpIr5t025W/ct4MI2YimaV2y2Pnl5LKJQQ=; b=a9ID3GWY1rTGSNZshZ7LQXECnpBkosXwFewVvJxcDFNdBGA4qjcRO2BcvEE5+wRFUA 4c8/HYpJE7UDpYGB0dDRFntFAMltBcRPaPeQ11D/IcAmPszKQ1xFyxHgzhutzddMFs3Q ApnFHCQddmQOpGT+WK2C55msBShdAQRa4H9Jodh0WmWJHYWn9uRbKuEq+Ygrl+CLqrGK Rfo8SWim6GohfPdFZLHY80l6PLuVZPRBvX7XVEgzCn4BGZq3Q/bKer369hGmJt8fr/Lh gTGqtmiO74+zrORx2xgvR6uRXJf0vQsyM6fAEBxaZ1+NWzPlCUS2WNcJfLhJJrDlxxeq uCZg== X-Gm-Message-State: AOAM532iAKOVnAMm/VojbRuP/NOFbwM27oZpG1hGF1xgcqgtBKnj1h7w f+H/LrRKREi32n8pZBQsPUbscTrANmuJvYGzx5QxVnwiFBAJVkPc9Tr1xymVpQCuwvHbMOgzb88 5MU9qG09Blf1Bn7qpFikw1P0= X-Received: by 2002:ac8:3836:: with SMTP id q51mr1875670qtb.41.1598626525327; Fri, 28 Aug 2020 07:55:25 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwTyv6Dcvf7JIMnb6Tl0QbVqispJtEs2IxGCkvKAa5tM3L596s/Au8e2J9bLRlyfSveblr7UA== X-Received: by 2002:ac8:3836:: with SMTP id q51mr1875649qtb.41.1598626525042; Fri, 28 Aug 2020 07:55:25 -0700 (PDT) Received: from trix.remote.csb (075-142-250-213.res.spectrum.com. [75.142.250.213]) by smtp.gmail.com with ESMTPSA id w36sm1206414qtc.48.2020.08.28.07.55.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 28 Aug 2020 07:55:24 -0700 (PDT) From: trix@redhat.com To: corbet@lwn.net, mchehab@kernel.org, natechancellor@gmail.com, ndesaulniers@google.com Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Tom Rix Subject: [PATCH] media: ov7670: check status of ov7670_read Date: Fri, 28 Aug 2020 07:55:18 -0700 Message-Id: <20200828145518.26324-1-trix@redhat.com> X-Mailer: git-send-email 2.18.1 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Tom Rix clang static analysis flags this representative problem drivers/media/i2c/ov7670.c:1463:9: warning: Assigned value is garbage or undefined *value = gain; ^ ~~~~ gain is set by a successful call to ov7670_read() So check that ov7670_read() is successful. The remaining static analysis problems are false positives. There appears to be a limitation with checking the aggregated returns. Signed-off-by: Tom Rix --- drivers/media/i2c/ov7670.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c index b42b289faaef..001d4b09db72 100644 --- a/drivers/media/i2c/ov7670.c +++ b/drivers/media/i2c/ov7670.c @@ -929,6 +929,8 @@ static int ov7670_set_hw(struct v4l2_subdev *sd, int hstart, int hstop, ret = ov7670_write(sd, REG_HSTART, (hstart >> 3) & 0xff); ret += ov7670_write(sd, REG_HSTOP, (hstop >> 3) & 0xff); ret += ov7670_read(sd, REG_HREF, &v); + if (ret) + return ret; v = (v & 0xc0) | ((hstop & 0x7) << 3) | (hstart & 0x7); msleep(10); ret += ov7670_write(sd, REG_HREF, v); @@ -938,6 +940,8 @@ static int ov7670_set_hw(struct v4l2_subdev *sd, int hstart, int hstop, ret += ov7670_write(sd, REG_VSTART, (vstart >> 2) & 0xff); ret += ov7670_write(sd, REG_VSTOP, (vstop >> 2) & 0xff); ret += ov7670_read(sd, REG_VREF, &v); + if (ret) + return ret; v = (v & 0xf0) | ((vstop & 0x3) << 2) | (vstart & 0x3); msleep(10); ret += ov7670_write(sd, REG_VREF, v); @@ -1460,6 +1464,8 @@ static int ov7670_g_gain(struct v4l2_subdev *sd, __s32 *value) unsigned char gain; ret = ov7670_read(sd, REG_GAIN, &gain); + if (ret) + return ret; *value = gain; return ret; } @@ -1470,11 +1476,14 @@ static int ov7670_s_gain(struct v4l2_subdev *sd, int value) unsigned char com8; ret = ov7670_write(sd, REG_GAIN, value & 0xff); + if (ret) + return ret; /* Have to turn off AGC as well */ - if (ret == 0) { - ret = ov7670_read(sd, REG_COM8, &com8); - ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AGC); - } + ret = ov7670_read(sd, REG_COM8, &com8); + if (ret) + return ret; + ret = ov7670_write(sd, REG_COM8, com8 & ~COM8_AGC); + return ret; }