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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 40941C433F5 for ; Tue, 16 Nov 2021 19:18:03 +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 0EBE663220 for ; Tue, 16 Nov 2021 19:18:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 0EBE663220 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D4A166E10F; Tue, 16 Nov 2021 19:18:01 +0000 (UTC) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by gabe.freedesktop.org (Postfix) with ESMTPS id 25FBB6E10F for ; Tue, 16 Nov 2021 19:18:00 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id D661E63223; Tue, 16 Nov 2021 19:17:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637090279; bh=EjfK6ywtkTbYiXTxOr4yEkJELrvwgwMVwqnEQgNPO2Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=frWfIpfU8B8hdkehcTUBtDi0OnSNOB/Kx9yM4kvNjk0KQY6XP2Q4N/+wyYk453KVB qKPWbovxQmJnL5hkSZ78JlgSCKz8hkfog2Y3udhiAz6b1orNHa5g0GeBwrWj8MU+f/ gObcCeD9SXptakUNFJFu1FwXYyNCs6us0dDhqXaelLJhY0EgxC4mGKHH6SLytM+oTA +p7TSvdz14QHPT25mEfOSCoZkWkBp8exNTz2nuJ9Il5cHJdJYtTFNmJJ4qxrB75NZa dPpWzEMfNBn8LTQ6753Sg2CxnpOv82xgEq8+Mg0cf/ZAJGCEfq6Avw18ut9jJhJgOZ UxkF/T+6gpiCg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 5.15 03/65] backlight: Propagate errors from get_brightness() Date: Tue, 16 Nov 2021 14:16:48 -0500 Message-Id: <20211116191754.2419097-3-sashal@kernel.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20211116191754.2419097-1-sashal@kernel.org> References: <20211116191754.2419097-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit 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: Sasha Levin , Daniel Thompson , jingoohan1@gmail.com, =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= , dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, Lee Jones Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Thomas Weißschuh [ Upstream commit 563edf85ce18a90dd0a7b39e279a691d937205f6 ] backlight.h documents "struct backlight_ops->get_brightness()" to return a negative errno on failure. So far these errors have not been handled in the backlight core. This leads to negative values being exposed through sysfs although only positive values are documented to be reported. Signed-off-by: Thomas Weißschuh Reviewed-by: Daniel Thompson Signed-off-by: Lee Jones Signed-off-by: Sasha Levin --- drivers/video/backlight/backlight.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c index 537fe1b376ad7..4658cfb75aa28 100644 --- a/drivers/video/backlight/backlight.c +++ b/drivers/video/backlight/backlight.c @@ -292,10 +292,13 @@ static ssize_t actual_brightness_show(struct device *dev, struct backlight_device *bd = to_backlight_device(dev); mutex_lock(&bd->ops_lock); - if (bd->ops && bd->ops->get_brightness) - rc = sprintf(buf, "%d\n", bd->ops->get_brightness(bd)); - else + if (bd->ops && bd->ops->get_brightness) { + rc = bd->ops->get_brightness(bd); + if (rc >= 0) + rc = sprintf(buf, "%d\n", rc); + } else { rc = sprintf(buf, "%d\n", bd->props.brightness); + } mutex_unlock(&bd->ops_lock); return rc; @@ -381,9 +384,18 @@ ATTRIBUTE_GROUPS(bl_device); void backlight_force_update(struct backlight_device *bd, enum backlight_update_reason reason) { + int brightness; + mutex_lock(&bd->ops_lock); - if (bd->ops && bd->ops->get_brightness) - bd->props.brightness = bd->ops->get_brightness(bd); + if (bd->ops && bd->ops->get_brightness) { + brightness = bd->ops->get_brightness(bd); + if (brightness >= 0) + bd->props.brightness = brightness; + else + dev_err(&bd->dev, + "Could not update brightness from device: %pe\n", + ERR_PTR(brightness)); + } mutex_unlock(&bd->ops_lock); backlight_generate_event(bd, reason); } -- 2.33.0