From patchwork Tue Jun 8 04:32:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Anand K. Mistry" X-Patchwork-Id: 12305449 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=-16.6 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 C92DEC47082 for ; Tue, 8 Jun 2021 06:34:29 +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 8C1B361208 for ; Tue, 8 Jun 2021 06:34:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8C1B361208 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.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 F301D6EAAA; Tue, 8 Jun 2021 06:34:28 +0000 (UTC) Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by gabe.freedesktop.org (Postfix) with ESMTPS id C3CAB6EA95 for ; Tue, 8 Jun 2021 04:32:47 +0000 (UTC) Received: by mail-yb1-xb4a.google.com with SMTP id w130-20020a25df880000b02905327e5d7f43so25261590ybg.3 for ; Mon, 07 Jun 2021 21:32:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=1CsAHJB1drzJFE9aMs2rQoto13RGg0fVp1ldOeOJhJM=; b=AODPeS3Rxy2dCzZVvlT77V++MmhgHwq/LXwUy62+WDULLkPs3l7t2Y3YlSU2OjGQxR wRSr6oKoRjTEq51NPDaNczweGae+Jm19rFf8p0D5OaFId+n1nPwvgzxFuLh4LXw1S3QA MlDb9Z41YtIo7OVegofT3m75hTP5y4ZKA8kLLhHCTMA3VMmJxMvAugXCIMSbiEfuHiPX l+2sM+hwGu4aP8yjEWplKd/vPOAJeenAlCNz4bOpqFQQmQe5Eiee/FvebF7i5MxXku5F PHbrhdGGqnsemAsDaDo5A53MJ4cVUbzYoHZdk1btN6z0Gl0BwAEeWgU7kEOQooBIeWs0 GOLA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=1CsAHJB1drzJFE9aMs2rQoto13RGg0fVp1ldOeOJhJM=; b=lOFPT4E3rP+PewIREHCrhra1NDV3QHOSZ5C4GCbJkheOEx8MW4sAjg6Tq3tjclcgKz 45qX4DfUeWF3RPb7L5L943FUS6mmB9jNT7IsM8XFxGEHnJmhtV9VX4oBCLxrlL1hpTcp BMHCZ+W+p4m11/HOIAUJloGoRAWSUoPkRNK8yUDrMHxvf0AhvqXoliSISkxUbdYXqcfn UtkLl7Ql1sx2/A/kz4zZdknPwh3KXek/TVb9QlKYcD++hbkyDXn0qHp9qOnfZ1K+Y9qL meTbl2wRCDMLb/JO7z5H8qO4JUoVpzDUQFSxHez7dzllL+88wBAaDmCpHsE5J8t7i259 dcjw== X-Gm-Message-State: AOAM531kmn/5DISMmXCpzAsdt1LDvGupeybScEPDHi4RZ45qboQdImbl jsYKiQpB1806dWLJCSlKyCbC8luWbhf2 X-Google-Smtp-Source: ABdhPJzGFYSJkGjEYy0wczei19iWM6Y/PFAcqGhaMiTDjHXzZj8TJzkLVLUqX7h6ji794vCiYrmvD3iMRwb6 X-Received: from nandos.syd.corp.google.com ([2401:fa00:9:14:7455:f4f3:5253:80b3]) (user=amistry job=sendgmr) by 2002:a25:7a41:: with SMTP id v62mr28852515ybc.225.1623126766754; Mon, 07 Jun 2021 21:32:46 -0700 (PDT) Date: Tue, 8 Jun 2021 14:32:38 +1000 Message-Id: <20210608143159.1.I230026301243fbcee23d408c75aa468c1fec58f7@changeid> Mime-Version: 1.0 X-Mailer: git-send-email 2.32.0.rc1.229.g3e70b5a671-goog Subject: [PATCH] drm/amd/display: Fix error code on failure to set brightness From: Anand K Mistry To: amd-gfx@lists.freedesktop.org X-Mailman-Approved-At: Tue, 08 Jun 2021 06:34:28 +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: Anand K Mistry , Eryk Brol , David Airlie , Qingqing Zhuo , Wayne Lin , Rodrigo Siqueira , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Nicholas Kazlauskas , Leo Li , Aurabindo Pillai , Alex Deucher , Nikola Cornij , =?utf-8?q?Christian_K=C3=B6nig?= Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The backlight_ops.update_status function is required to return a negative error code on failure. Returning a positive code may be interpreted as a success. This is true for the 'brightness' sysfs file, which passes through a non-zero value as the return value of the write() syscall. This is interpreted in user-space as a successful write of 1 character, which is obviously wrong. It's not clear exactly what error code to use, but EINVAL should be reasonable. Signed-off-by: Anand K Mistry --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 652cc1a0e450..ad322613390d 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -3431,7 +3431,7 @@ static int amdgpu_dm_backlight_update_status(struct backlight_device *bd) else rc = dc_link_set_backlight_level(dm->backlight_link, brightness, 0); - return rc ? 0 : 1; + return rc ? 0 : -EINVAL; } static int amdgpu_dm_backlight_get_brightness(struct backlight_device *bd)