From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AFEDEC433DF for ; Mon, 3 Aug 2020 13:04:28 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 81789205CB for ; Mon, 3 Aug 2020 13:04:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="MxXS7aXG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 81789205CB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 014A06E267; Mon, 3 Aug 2020 13:04:29 +0000 (UTC) Received: from mail-ed1-x541.google.com (mail-ed1-x541.google.com [IPv6:2a00:1450:4864:20::541]) by gabe.freedesktop.org (Postfix) with ESMTPS id 573136EB79; Sat, 1 Aug 2020 12:24:37 +0000 (UTC) Received: by mail-ed1-x541.google.com with SMTP id l23so10420144edv.11; Sat, 01 Aug 2020 05:24:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=mTab8JNvsgo4CL+J2E65GCxL4zVDcvJICP1+e2MGiww=; b=MxXS7aXGg49OI8aq1o2JxQSacx3GEkx7XRc4h3ldURK6zBJgpz5BCs4TCQi9vzW8bw 6N5rmJ/Bc2EsNZmNEy95m4VrSdD6S36XHIE0bXDvbmHdvv8Ihd/DN3YqOot8+XNsBn4K uH6Ip0XLj/CLkS7OQbIMeU5cG1JmDbAF6R4dkjrmVllWjiJc6lq/K7WJN3y20CFnB+Zq Veh4WXw6cFj5wfDJzSErjSaJ/GQ1p/YmseYNttpG96RLDnixkmg9o75N4xiBxD0qqPsJ 1iL8Qj7buxqLPP29VEWOUOsDSz4OPW5lGkFWyKdBy9bfKl3Yd4OWQ3uoiFlz2n2kpCGD NGZg== 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:in-reply-to :references; bh=mTab8JNvsgo4CL+J2E65GCxL4zVDcvJICP1+e2MGiww=; b=fGFpXHb5yFqLC9rsaj6KGPNxRHw/BD55LHEjfJf57GrWsRG1DPtB3y0d40tmT4UwOB UejZRlmSWtUOz8SGwLV3zmnMSK6NbJhJ5ruB0TrN/HL2w3Ty4jgIv6mP+4bsAxExX5Cb 7/1yt4FFCcLy9MT9tQQy+JaBXRUCH+McTkhae36sZels85MO2zddWBDBHOVL9xNj13AT YaJznRNkazVCfP8OkbT8BJZuhAqg07e+wCFbKMyY/FNStM/z98W4EAorsKsNmCqhJcek fG74F/6DX/VOffcYWup2lCTRYzc4T4KAqz15a1qClmwazEqs+ZJ+8f6BVkN3RQKHyxfX Mo8A== X-Gm-Message-State: AOAM533H50KeZ6VWpTStO9VPEhEYBHt1eNPvf3ThRtATFQFx32gDTatI RPXHjMBcXR2ISxVT3sUDGYM= X-Google-Smtp-Source: ABdhPJyNuqCc/8r6/A/7Q7T/LnVDBWUQ9SzPEt/TNIqjoVA3EMIMDnSI53A+QOmplMa8tW5cITLjzA== X-Received: by 2002:aa7:d5d0:: with SMTP id d16mr7805559eds.212.1596284675988; Sat, 01 Aug 2020 05:24:35 -0700 (PDT) Received: from net.saheed (95C84E0A.dsl.pool.telekom.hu. [149.200.78.10]) by smtp.gmail.com with ESMTPSA id a101sm12083131edf.76.2020.08.01.05.24.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 01 Aug 2020 05:24:35 -0700 (PDT) From: "Saheed O. Bolarinwa" To: helgaas@kernel.org, David Airlie , Daniel Vetter Date: Sat, 1 Aug 2020 13:24:38 +0200 Message-Id: <20200801112446.149549-10-refactormyself@gmail.com> X-Mailer: git-send-email 2.18.4 In-Reply-To: <20200801112446.149549-1-refactormyself@gmail.com> References: <20200801112446.149549-1-refactormyself@gmail.com> X-Mailman-Approved-At: Mon, 03 Aug 2020 13:04:28 +0000 Subject: [Intel-gfx] [RFC PATCH 09/17] drm/i915/vga: Drop uses of pci_read_config_*() return value X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Saheed O. Bolarinwa" , intel-gfx@lists.freedesktop.org, skhan@linuxfoundation.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-pci@vger.kernel.org, bjorn@helgaas.com, linux-kernel-mentees@lists.linuxfoundation.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" The return value of pci_read_config_*() may not indicate a device error. However, the value read by these functions is more likely to indicate this kind of error. This presents two overlapping ways of reporting errors and complicates error checking. It is possible to move to one single way of checking for error if the dependency on the return value of these functions is removed, then it can later be made to return void. Remove all uses of the return value of pci_read_config_*(). Check the actual value read for ~0. In this case, ~0 is an invalid value thus it indicates some kind of error. Suggested-by: Bjorn Helgaas Signed-off-by: Saheed O. Bolarinwa --- drivers/gpu/drm/i915/display/intel_vga.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_vga.c b/drivers/gpu/drm/i915/display/intel_vga.c index be333699c515..6f9406699c9d 100644 --- a/drivers/gpu/drm/i915/display/intel_vga.c +++ b/drivers/gpu/drm/i915/display/intel_vga.c @@ -99,7 +99,8 @@ intel_vga_set_state(struct drm_i915_private *i915, bool enable_decode) unsigned int reg = INTEL_GEN(i915) >= 6 ? SNB_GMCH_CTRL : INTEL_GMCH_CTRL; u16 gmch_ctrl; - if (pci_read_config_word(i915->bridge_dev, reg, &gmch_ctrl)) { + pci_read_config_word(i915->bridge_dev, reg, &gmch_ctrl); + if (gmch_ctrl == (u16)~0) { drm_err(&i915->drm, "failed to read control word\n"); return -EIO; } -- 2.18.4 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C95C8C433E1 for ; Sat, 1 Aug 2020 12:24:41 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9D81E2087C for ; Sat, 1 Aug 2020 12:24:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="MxXS7aXG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9D81E2087C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-kernel-mentees-bounces@lists.linuxfoundation.org Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id 80C68887D9; Sat, 1 Aug 2020 12:24:41 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 7P1p1uyfUGDM; Sat, 1 Aug 2020 12:24:40 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by hemlock.osuosl.org (Postfix) with ESMTP id D60D9887BB; Sat, 1 Aug 2020 12:24:40 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id BFCE5C0888; Sat, 1 Aug 2020 12:24:40 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) by lists.linuxfoundation.org (Postfix) with ESMTP id B1A8AC004D for ; Sat, 1 Aug 2020 12:24:38 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id A75C9203E7 for ; Sat, 1 Aug 2020 12:24:38 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id C4kFNKuLHsCT for ; Sat, 1 Aug 2020 12:24:37 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail-ed1-f68.google.com (mail-ed1-f68.google.com [209.85.208.68]) by silver.osuosl.org (Postfix) with ESMTPS id 8F343203DF for ; Sat, 1 Aug 2020 12:24:37 +0000 (UTC) Received: by mail-ed1-f68.google.com with SMTP id o10so14440004edh.6 for ; Sat, 01 Aug 2020 05:24:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=mTab8JNvsgo4CL+J2E65GCxL4zVDcvJICP1+e2MGiww=; b=MxXS7aXGg49OI8aq1o2JxQSacx3GEkx7XRc4h3ldURK6zBJgpz5BCs4TCQi9vzW8bw 6N5rmJ/Bc2EsNZmNEy95m4VrSdD6S36XHIE0bXDvbmHdvv8Ihd/DN3YqOot8+XNsBn4K uH6Ip0XLj/CLkS7OQbIMeU5cG1JmDbAF6R4dkjrmVllWjiJc6lq/K7WJN3y20CFnB+Zq Veh4WXw6cFj5wfDJzSErjSaJ/GQ1p/YmseYNttpG96RLDnixkmg9o75N4xiBxD0qqPsJ 1iL8Qj7buxqLPP29VEWOUOsDSz4OPW5lGkFWyKdBy9bfKl3Yd4OWQ3uoiFlz2n2kpCGD NGZg== 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:in-reply-to :references; bh=mTab8JNvsgo4CL+J2E65GCxL4zVDcvJICP1+e2MGiww=; b=VpNQXLMqbmrHeEC1hT1LKWHKcq/nNdu7EdEsoyb35tRQ14YHFUZZf3NpCXYqfbDrrM VqdUFx5C6R3tuEfpoR6NG4xcDuxdqVmVpc1IyGkFD9Fy9fKmJDkYrG4J1mYZWWNIIoBz GvwhTI+PqYb1Es3JY9V6Gf+yAz11Gj6fTtumoUNUmT/vrMnURjtAGmtT/zEp2ADGrIaE fCHkn/ZJZjk6b5e08uCxnw50tVQfY9wV/VvjiEGohOc2qLQci8Y0JITYSQWNazeeFS1i REECQTWgypD4YCiuJ+hrakKY0PeUqaCuXoOC9OzyLP+MGgMFm2/g4X78jcohg95LsgV7 sX1w== X-Gm-Message-State: AOAM530RcWyFZ8nTgLfCF7vHlMruwan5r79YTP3/yxjVNl0CLuF2WDD0 KXC5WEn7w0E8Um4Mg3ko9GE= X-Google-Smtp-Source: ABdhPJyNuqCc/8r6/A/7Q7T/LnVDBWUQ9SzPEt/TNIqjoVA3EMIMDnSI53A+QOmplMa8tW5cITLjzA== X-Received: by 2002:aa7:d5d0:: with SMTP id d16mr7805559eds.212.1596284675988; Sat, 01 Aug 2020 05:24:35 -0700 (PDT) Received: from net.saheed (95C84E0A.dsl.pool.telekom.hu. [149.200.78.10]) by smtp.gmail.com with ESMTPSA id a101sm12083131edf.76.2020.08.01.05.24.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 01 Aug 2020 05:24:35 -0700 (PDT) From: "Saheed O. Bolarinwa" To: helgaas@kernel.org, David Airlie , Daniel Vetter Date: Sat, 1 Aug 2020 13:24:38 +0200 Message-Id: <20200801112446.149549-10-refactormyself@gmail.com> X-Mailer: git-send-email 2.18.4 In-Reply-To: <20200801112446.149549-1-refactormyself@gmail.com> References: <20200801112446.149549-1-refactormyself@gmail.com> Cc: Joonas Lahtinen , "Saheed O. Bolarinwa" , intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, Jani Nikula , Rodrigo Vivi , dri-devel@lists.freedesktop.org, linux-pci@vger.kernel.org, linux-kernel-mentees@lists.linuxfoundation.org Subject: [Linux-kernel-mentees] [RFC PATCH 09/17] drm/i915/vga: Drop uses of pci_read_config_*() return value X-BeenThere: linux-kernel-mentees@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-kernel-mentees-bounces@lists.linuxfoundation.org Sender: "Linux-kernel-mentees" The return value of pci_read_config_*() may not indicate a device error. However, the value read by these functions is more likely to indicate this kind of error. This presents two overlapping ways of reporting errors and complicates error checking. It is possible to move to one single way of checking for error if the dependency on the return value of these functions is removed, then it can later be made to return void. Remove all uses of the return value of pci_read_config_*(). Check the actual value read for ~0. In this case, ~0 is an invalid value thus it indicates some kind of error. Suggested-by: Bjorn Helgaas Signed-off-by: Saheed O. Bolarinwa --- drivers/gpu/drm/i915/display/intel_vga.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_vga.c b/drivers/gpu/drm/i915/display/intel_vga.c index be333699c515..6f9406699c9d 100644 --- a/drivers/gpu/drm/i915/display/intel_vga.c +++ b/drivers/gpu/drm/i915/display/intel_vga.c @@ -99,7 +99,8 @@ intel_vga_set_state(struct drm_i915_private *i915, bool enable_decode) unsigned int reg = INTEL_GEN(i915) >= 6 ? SNB_GMCH_CTRL : INTEL_GMCH_CTRL; u16 gmch_ctrl; - if (pci_read_config_word(i915->bridge_dev, reg, &gmch_ctrl)) { + pci_read_config_word(i915->bridge_dev, reg, &gmch_ctrl); + if (gmch_ctrl == (u16)~0) { drm_err(&i915->drm, "failed to read control word\n"); return -EIO; } -- 2.18.4 _______________________________________________ Linux-kernel-mentees mailing list Linux-kernel-mentees@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 81351C433E1 for ; Sat, 1 Aug 2020 12:25:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 615EC208A9 for ; Sat, 1 Aug 2020 12:25:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="MxXS7aXG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729043AbgHAMZS (ORCPT ); Sat, 1 Aug 2020 08:25:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54216 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728933AbgHAMYh (ORCPT ); Sat, 1 Aug 2020 08:24:37 -0400 Received: from mail-ed1-x543.google.com (mail-ed1-x543.google.com [IPv6:2a00:1450:4864:20::543]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3826BC06174A; Sat, 1 Aug 2020 05:24:37 -0700 (PDT) Received: by mail-ed1-x543.google.com with SMTP id bs17so5368392edb.1; Sat, 01 Aug 2020 05:24:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=mTab8JNvsgo4CL+J2E65GCxL4zVDcvJICP1+e2MGiww=; b=MxXS7aXGg49OI8aq1o2JxQSacx3GEkx7XRc4h3ldURK6zBJgpz5BCs4TCQi9vzW8bw 6N5rmJ/Bc2EsNZmNEy95m4VrSdD6S36XHIE0bXDvbmHdvv8Ihd/DN3YqOot8+XNsBn4K uH6Ip0XLj/CLkS7OQbIMeU5cG1JmDbAF6R4dkjrmVllWjiJc6lq/K7WJN3y20CFnB+Zq Veh4WXw6cFj5wfDJzSErjSaJ/GQ1p/YmseYNttpG96RLDnixkmg9o75N4xiBxD0qqPsJ 1iL8Qj7buxqLPP29VEWOUOsDSz4OPW5lGkFWyKdBy9bfKl3Yd4OWQ3uoiFlz2n2kpCGD NGZg== 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:in-reply-to :references; bh=mTab8JNvsgo4CL+J2E65GCxL4zVDcvJICP1+e2MGiww=; b=pa8PyqiRXCleEs8MJbgKvUwLyhtbQQKu/3LxyfJE9G9tvCw/rM1DitlyNwNeLnHt/q mmjTUBnfiX5t3aWU6JVhZ03SdIITbjognEdB0rCuU/FsMt+ICDIx71iz2SLMKwYgTzqG kij8iQ4YfXDa7vKTxTANaUB1UrcdFtKuqPtFPIQ3NuBCRWj9mMVLS9NXH7+V7WFQQ0i8 mRFm5ViuF3ydIDiD5m9asVBX4TwZdqLLg90Eo+2Cbb3PuaffIRRkK7RYiWy1JAZa5iPP ZZOdBvCHUMCzn7YVxpsH5iedrviT+WwT5cPQvNqM8BpVM9C7twVKJN6ndStIcxdddgi7 kYdA== X-Gm-Message-State: AOAM533934lHCn1H2Qf5XdkoTyeyge9gkiIKcjj5cb0YC18dmILmUg9y oTOQh/LUlPLi37H6hXaYj8Q= X-Google-Smtp-Source: ABdhPJyNuqCc/8r6/A/7Q7T/LnVDBWUQ9SzPEt/TNIqjoVA3EMIMDnSI53A+QOmplMa8tW5cITLjzA== X-Received: by 2002:aa7:d5d0:: with SMTP id d16mr7805559eds.212.1596284675988; Sat, 01 Aug 2020 05:24:35 -0700 (PDT) Received: from net.saheed (95C84E0A.dsl.pool.telekom.hu. [149.200.78.10]) by smtp.gmail.com with ESMTPSA id a101sm12083131edf.76.2020.08.01.05.24.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 01 Aug 2020 05:24:35 -0700 (PDT) From: "Saheed O. Bolarinwa" To: helgaas@kernel.org, David Airlie , Daniel Vetter Cc: "Saheed O. Bolarinwa" , bjorn@helgaas.com, skhan@linuxfoundation.org, linux-kernel-mentees@lists.linuxfoundation.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Subject: [RFC PATCH 09/17] drm/i915/vga: Drop uses of pci_read_config_*() return value Date: Sat, 1 Aug 2020 13:24:38 +0200 Message-Id: <20200801112446.149549-10-refactormyself@gmail.com> X-Mailer: git-send-email 2.18.4 In-Reply-To: <20200801112446.149549-1-refactormyself@gmail.com> References: <20200801112446.149549-1-refactormyself@gmail.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The return value of pci_read_config_*() may not indicate a device error. However, the value read by these functions is more likely to indicate this kind of error. This presents two overlapping ways of reporting errors and complicates error checking. It is possible to move to one single way of checking for error if the dependency on the return value of these functions is removed, then it can later be made to return void. Remove all uses of the return value of pci_read_config_*(). Check the actual value read for ~0. In this case, ~0 is an invalid value thus it indicates some kind of error. Suggested-by: Bjorn Helgaas Signed-off-by: Saheed O. Bolarinwa --- drivers/gpu/drm/i915/display/intel_vga.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_vga.c b/drivers/gpu/drm/i915/display/intel_vga.c index be333699c515..6f9406699c9d 100644 --- a/drivers/gpu/drm/i915/display/intel_vga.c +++ b/drivers/gpu/drm/i915/display/intel_vga.c @@ -99,7 +99,8 @@ intel_vga_set_state(struct drm_i915_private *i915, bool enable_decode) unsigned int reg = INTEL_GEN(i915) >= 6 ? SNB_GMCH_CTRL : INTEL_GMCH_CTRL; u16 gmch_ctrl; - if (pci_read_config_word(i915->bridge_dev, reg, &gmch_ctrl)) { + pci_read_config_word(i915->bridge_dev, reg, &gmch_ctrl); + if (gmch_ctrl == (u16)~0) { drm_err(&i915->drm, "failed to read control word\n"); return -EIO; } -- 2.18.4 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4159EC433E0 for ; Mon, 3 Aug 2020 08:20:44 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0EBB6206E2 for ; Mon, 3 Aug 2020 08:20:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="MxXS7aXG" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0EBB6206E2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 471F9890D2; Mon, 3 Aug 2020 08:20:38 +0000 (UTC) Received: from mail-ed1-x541.google.com (mail-ed1-x541.google.com [IPv6:2a00:1450:4864:20::541]) by gabe.freedesktop.org (Postfix) with ESMTPS id 573136EB79; Sat, 1 Aug 2020 12:24:37 +0000 (UTC) Received: by mail-ed1-x541.google.com with SMTP id l23so10420144edv.11; Sat, 01 Aug 2020 05:24:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=mTab8JNvsgo4CL+J2E65GCxL4zVDcvJICP1+e2MGiww=; b=MxXS7aXGg49OI8aq1o2JxQSacx3GEkx7XRc4h3ldURK6zBJgpz5BCs4TCQi9vzW8bw 6N5rmJ/Bc2EsNZmNEy95m4VrSdD6S36XHIE0bXDvbmHdvv8Ihd/DN3YqOot8+XNsBn4K uH6Ip0XLj/CLkS7OQbIMeU5cG1JmDbAF6R4dkjrmVllWjiJc6lq/K7WJN3y20CFnB+Zq Veh4WXw6cFj5wfDJzSErjSaJ/GQ1p/YmseYNttpG96RLDnixkmg9o75N4xiBxD0qqPsJ 1iL8Qj7buxqLPP29VEWOUOsDSz4OPW5lGkFWyKdBy9bfKl3Yd4OWQ3uoiFlz2n2kpCGD NGZg== 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:in-reply-to :references; bh=mTab8JNvsgo4CL+J2E65GCxL4zVDcvJICP1+e2MGiww=; b=fGFpXHb5yFqLC9rsaj6KGPNxRHw/BD55LHEjfJf57GrWsRG1DPtB3y0d40tmT4UwOB UejZRlmSWtUOz8SGwLV3zmnMSK6NbJhJ5ruB0TrN/HL2w3Ty4jgIv6mP+4bsAxExX5Cb 7/1yt4FFCcLy9MT9tQQy+JaBXRUCH+McTkhae36sZels85MO2zddWBDBHOVL9xNj13AT YaJznRNkazVCfP8OkbT8BJZuhAqg07e+wCFbKMyY/FNStM/z98W4EAorsKsNmCqhJcek fG74F/6DX/VOffcYWup2lCTRYzc4T4KAqz15a1qClmwazEqs+ZJ+8f6BVkN3RQKHyxfX Mo8A== X-Gm-Message-State: AOAM533H50KeZ6VWpTStO9VPEhEYBHt1eNPvf3ThRtATFQFx32gDTatI RPXHjMBcXR2ISxVT3sUDGYM= X-Google-Smtp-Source: ABdhPJyNuqCc/8r6/A/7Q7T/LnVDBWUQ9SzPEt/TNIqjoVA3EMIMDnSI53A+QOmplMa8tW5cITLjzA== X-Received: by 2002:aa7:d5d0:: with SMTP id d16mr7805559eds.212.1596284675988; Sat, 01 Aug 2020 05:24:35 -0700 (PDT) Received: from net.saheed (95C84E0A.dsl.pool.telekom.hu. [149.200.78.10]) by smtp.gmail.com with ESMTPSA id a101sm12083131edf.76.2020.08.01.05.24.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 01 Aug 2020 05:24:35 -0700 (PDT) From: "Saheed O. Bolarinwa" To: helgaas@kernel.org, David Airlie , Daniel Vetter Subject: [RFC PATCH 09/17] drm/i915/vga: Drop uses of pci_read_config_*() return value Date: Sat, 1 Aug 2020 13:24:38 +0200 Message-Id: <20200801112446.149549-10-refactormyself@gmail.com> X-Mailer: git-send-email 2.18.4 In-Reply-To: <20200801112446.149549-1-refactormyself@gmail.com> References: <20200801112446.149549-1-refactormyself@gmail.com> X-Mailman-Approved-At: Mon, 03 Aug 2020 08:20:37 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Saheed O. Bolarinwa" , intel-gfx@lists.freedesktop.org, skhan@linuxfoundation.org, linux-kernel@vger.kernel.org, Rodrigo Vivi , dri-devel@lists.freedesktop.org, linux-pci@vger.kernel.org, bjorn@helgaas.com, linux-kernel-mentees@lists.linuxfoundation.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The return value of pci_read_config_*() may not indicate a device error. However, the value read by these functions is more likely to indicate this kind of error. This presents two overlapping ways of reporting errors and complicates error checking. It is possible to move to one single way of checking for error if the dependency on the return value of these functions is removed, then it can later be made to return void. Remove all uses of the return value of pci_read_config_*(). Check the actual value read for ~0. In this case, ~0 is an invalid value thus it indicates some kind of error. Suggested-by: Bjorn Helgaas Signed-off-by: Saheed O. Bolarinwa --- drivers/gpu/drm/i915/display/intel_vga.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_vga.c b/drivers/gpu/drm/i915/display/intel_vga.c index be333699c515..6f9406699c9d 100644 --- a/drivers/gpu/drm/i915/display/intel_vga.c +++ b/drivers/gpu/drm/i915/display/intel_vga.c @@ -99,7 +99,8 @@ intel_vga_set_state(struct drm_i915_private *i915, bool enable_decode) unsigned int reg = INTEL_GEN(i915) >= 6 ? SNB_GMCH_CTRL : INTEL_GMCH_CTRL; u16 gmch_ctrl; - if (pci_read_config_word(i915->bridge_dev, reg, &gmch_ctrl)) { + pci_read_config_word(i915->bridge_dev, reg, &gmch_ctrl); + if (gmch_ctrl == (u16)~0) { drm_err(&i915->drm, "failed to read control word\n"); return -EIO; } -- 2.18.4 _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel