From patchwork Mon Jun 1 06:51:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sam Ravnborg X-Patchwork-Id: 11581463 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 E6295913 for ; Mon, 1 Jun 2020 06:52:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CE16520772 for ; Mon, 1 Jun 2020 06:52:22 +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="e2Fj5Mog" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726005AbgFAGwW (ORCPT ); Mon, 1 Jun 2020 02:52:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44848 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725283AbgFAGwW (ORCPT ); Mon, 1 Jun 2020 02:52:22 -0400 Received: from mail-lj1-x243.google.com (mail-lj1-x243.google.com [IPv6:2a00:1450:4864:20::243]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BA793C061A0E; Sun, 31 May 2020 23:52:21 -0700 (PDT) Received: by mail-lj1-x243.google.com with SMTP id m18so6757404ljo.5; Sun, 31 May 2020 23:52:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=18JbutLa3sEGZU8ji80y4T0HOoe/GimoCUZDbVyKY0E=; b=e2Fj5MogkKmmlicpZQIOcwOKcfsndqV5JSgZlnOJPZKp5N41Qkoah2I5L+kq+0n5xH 3wTRhIuHGWcFmhJecE6nLFQQEAgNEn0P5D72ORGOutadmzwdvFMXCoQlxfbmN+Myklzl rguVPFRYjbKEkUFrlPWeF5147m7T/7ELoYom48Fdu1C/F1qH4wKFR76529LX2cTBtgDz J5NlM9AJ/0Z7WJGmQPmbZ/x5QYxm5SBp2RdyIl0DAAuuUC7YBSK/2J2uKFoL0ntMGdnK dHZ/3Wy/+sVKJtZtQe2kQ67mTFb5aOlSC8FdrBm5kiY5ybts/i67pwFqK7AJm3E0cJYN 1jfw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=18JbutLa3sEGZU8ji80y4T0HOoe/GimoCUZDbVyKY0E=; b=VABIJrX0Da4XIj75CQtWiQqduaUd+9VtLvLy0UI3kYOIa6kNTW9wgYakp0vYtzXaKp fxOLwVyjBj0jpdrTT5bFFa6BX1FMk0fCIV/Ew8lG5cBEH3KJEhyjStL7b9JpueVLFviq N0Dxg1ecxoCNIqNsEuwSizfrxBDpqVDAwMbnqckSXVGOwcwci3IldUbG0MzU074ijqQH wJeLaFXb9RnXIjtJ3eQVIT04c9Ab+ffOxwSEj24cmnANhDVGHSSFZbXwYTUari/KYB3K Idax+FujdfZG6Naiyu/s7LRNdnb77IExdA9Mt9s2z+yyGrG95mQP/inKD5MyjCqXtdZU U07Q== X-Gm-Message-State: AOAM533YdfPasUtMPvoQ+hf+yJEPtSmDOKNfKc2+ypJ/xJl7B1mFl1xz q+/iOpH4cUDQnc/nNKGfPIk= X-Google-Smtp-Source: ABdhPJzTmzfyLe20++Ve5cRFiyoAQagMqwFVvs32L/FlmdwyctEw1qWH+8aNS3DXRsegMEk3+htxXg== X-Received: by 2002:a2e:4612:: with SMTP id t18mr4691823lja.212.1590994340242; Sun, 31 May 2020 23:52:20 -0700 (PDT) Received: from saturn.lan ([2a00:fd00:805f:db00:281d:a604:434c:a58d]) by smtp.gmail.com with ESMTPSA id e13sm2540462ljl.117.2020.05.31.23.52.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 31 May 2020 23:52:19 -0700 (PDT) From: Sam Ravnborg To: dri-devel@lists.freedesktop.org, Jingoo Han , Lee Jones , Daniel Thompson Cc: Andy Gross , Bartlomiej Zolnierkiewicz , Bjorn Andersson , Daniel Vetter , David Airlie , Emil Velikov , Jonathan Corbet , linux-arm-msm@vger.kernel.org, linux-pwm@vger.kernel.org, Maarten Lankhorst , Maxime Ripard , Michael Hennerich , patches@opensource.cirrus.com, Support Opensource , Thierry Reding , Thomas Zimmermann , Uwe Kleine-Konig , Peter Ujfalusi , Tomi Valkeinen , Sam Ravnborg Subject: [PATCH v3 02/13] backlight: add backlight_is_blank() Date: Mon, 1 Jun 2020 08:51:56 +0200 Message-Id: <20200601065207.492614-3-sam@ravnborg.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200601065207.492614-1-sam@ravnborg.org> References: <20200601065207.492614-1-sam@ravnborg.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The backlight support has two properties that express the state: - power - state It is un-documented and easy to get wrong. Add backlight_is_blank() helper to make it simpler for drivers to get the check of the state correct. A lot of drivers also includes checks for fb_blank. This check is redundant when the state is checked and thus not needed in this helper function. But added anyway to avoid introducing subtle bugs due to the creative use of fb_blank in some drivers. Introducing this helper will for some drivers results in added support for fb_blank. This will be a change in functionality, which will improve the backlight driver. Rolling out this helper to all relevant backlight drivers will eliminate almost all accesses to fb_blank. v3: - Clarified that the fb_blank support in backlight_is_blank() may result in functionality changes for the users (Emil) v2: - Added fb_blank condition (Daniel) Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Cc: Emil Velikov Cc: Daniel Vetter Cc: Lee Jones Cc: Daniel Thompson Cc: Jingoo Han Reviewed-by: Peter Ujfalusi --- include/linux/backlight.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/include/linux/backlight.h b/include/linux/backlight.h index c7d6b2e8c3b5..a0a083b35c47 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -175,6 +175,25 @@ static inline void backlight_put(struct backlight_device *bd) put_device(&bd->dev); } +/** + * backlight_is_blank - Return true if display is expected to be blank + * @bd: the backlight device + * + * Display is expected to be blank if any of these is true:: + * + * 1) if power in not UNBLANK + * 2) if fb_blank is not UNBLANK + * 3) if state indicate BLANK or SUSPENDED + * + * Returns true if display is expected to be blank, false otherwise. + */ +static inline bool backlight_is_blank(struct backlight_device *bd) +{ + return bd->props.power != FB_BLANK_UNBLANK || + bd->props.fb_blank != FB_BLANK_UNBLANK || + bd->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK); +} + extern struct backlight_device *backlight_device_register(const char *name, struct device *dev, void *devdata, const struct backlight_ops *ops, const struct backlight_properties *props);