From patchwork Sun Jul 19 08:07:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sam Ravnborg X-Patchwork-Id: 11672259 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 DB63C138C for ; Sun, 19 Jul 2020 08:08:20 +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 B9DA8208DB for ; Sun, 19 Jul 2020 08:08:20 +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="FeXCC5uW" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B9DA8208DB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ravnborg.org 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 9E4CC89FA6; Sun, 19 Jul 2020 08:08:12 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-lj1-x242.google.com (mail-lj1-x242.google.com [IPv6:2a00:1450:4864:20::242]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6889C89FA6 for ; Sun, 19 Jul 2020 08:08:10 +0000 (UTC) Received: by mail-lj1-x242.google.com with SMTP id f5so17026146ljj.10 for ; Sun, 19 Jul 2020 01:08:10 -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=nbqgxv/h5SeSHOXMolpp1BPamIvzkqESgLDvhPwqMhU=; b=FeXCC5uWIx+xcOi69FiCd1WNxp1c/0jhf4TeSjclL5MQ77bSEs6eYcrjtY3c5MC2Kd pXnWznTPbn1EC8xVG2HU9EqNJHM7HiZ7QY10MsYNw05o+K3H+g426JRiY2HJMomejE05 iknc8vjgLAXT9POoZMjTVAAqfs5H4ARBf8CJKejX7PxYmW92/4TWwbTtiu8DXMtrfxqc aj5eHo0ic5j/N+HCl+zgtVeGL7vcQroTB8o1+bHOZndpn+y3YdaLyW1GzDBKzupjA9oj axFgVOOEew7dJ/Uz0JNPWu1rv9a3MhJxNILabroCh+Zs8LIhuYrTktu6ljiNwd8+kp+C ekVw== 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=nbqgxv/h5SeSHOXMolpp1BPamIvzkqESgLDvhPwqMhU=; b=e4Z6C9yXGsi2Al952hr3+IrObIq69Eydf/S7rucmDApUV3GjaQ20Cu6RLnuSeZmE8m m556VXRGIoZWpdqHLKe3GwyrWt6WuUrXqhh7qkQPnu7T9z6iVedTKZTwIoIexI+6ru8z XeJtZ4PX59Tj+zLQBwepUK36+TqSXf5uJ1AiEBNNtBu759nPfsF+o/6FM49BRovnNj6w 7Ya+zrV/ZwNGu3k4dLl0GqkSl6LM27f/1gjOs+CghOT4imPzYdmKPbuhd6B+Kk94qdOF +PyBGdd6UALuJojT50FTWDSlZ7oCBGyNP4ZeKByyfJA9ns0C9OpPk/02t/9F0Kc8QJsc z75Q== X-Gm-Message-State: AOAM5339JXs8wH7PzMtdkeug9YB2vp+RtoQDnmE2FxNlcDcDdEJ2ZwXD KB97l4C40FbpnHiOlv63tQIPCa5YGdo= X-Google-Smtp-Source: ABdhPJyNcZ5EJA4eLpDENaVjpjfmWTUn7NaB1GxtAlwE27Hcf1R33YPb6lzXpJNzB9cCUKkhmuZ2AQ== X-Received: by 2002:a2e:9cc2:: with SMTP id g2mr7060773ljj.442.1595146088632; Sun, 19 Jul 2020 01:08:08 -0700 (PDT) Received: from saturn.lan ([2a00:fd00:805f:db00:d5fe:fe9c:fc06:b74c]) by smtp.gmail.com with ESMTPSA id 72sm732407lfh.97.2020.07.19.01.08.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 19 Jul 2020 01:08:08 -0700 (PDT) From: Sam Ravnborg To: dri-devel@lists.freedesktop.org, Jingoo Han , Lee Jones , Daniel Thompson Subject: [PATCH v5 04/19] backlight: improve backlight_properties documentation Date: Sun, 19 Jul 2020 10:07:28 +0200 Message-Id: <20200719080743.8560-5-sam@ravnborg.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200719080743.8560-1-sam@ravnborg.org> References: <20200719080743.8560-1-sam@ravnborg.org> MIME-Version: 1.0 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: linux-pwm@vger.kernel.org, Support Opensource , Michael Hennerich , Bartlomiej Zolnierkiewicz , David Airlie , Daniel Vetter , Tomi Valkeinen , Jonathan Corbet , Emil Velikov , Bjorn Andersson , Peter Ujfalusi , Andy Gross , Thierry Reding , Thomas Zimmermann , linux-arm-msm@vger.kernel.org, Uwe Kleine-Konig , Sam Ravnborg , patches@opensource.cirrus.com Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Improve the documentation for backlight_properties and adapt it to kernel-doc style. v3: - Added missing '@' in kernel-doc v2: - Added into for each field (Daniel) - Re-written some parts to explain what to do, rather than what not to do. Partly based on suggestions from the review (Daniel) Signed-off-by: Sam Ravnborg Reviewed-by: Daniel Thompson Reviewed-by: Emil Velikov Cc: Lee Jones Cc: Daniel Thompson Cc: Jingoo Han --- include/linux/backlight.h | 96 ++++++++++++++++++++++++++++++++++----- 1 file changed, 85 insertions(+), 11 deletions(-) diff --git a/include/linux/backlight.h b/include/linux/backlight.h index dfb43ee02ea0..10518b00b059 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -117,28 +117,102 @@ struct backlight_ops { int (*check_fb)(struct backlight_device *bd, struct fb_info *info); }; -/* This structure defines all the properties of a backlight */ +/** + * struct backlight_properties - backlight properties + * + * This structure defines all the properties of a backlight. + */ struct backlight_properties { - /* Current User requested brightness (0 - max_brightness) */ + /** + * @brightness: The current brightness requested by the user. + * + * The backlight core makes sure the range is (0 to max_brightness) + * when the brightness is set via the sysfs attribute: + * /sys/class/backlight//brightness. + * + * This value can be set in the backlight_properties passed + * to devm_backlight_device_register() to set a default brightness + * value. + */ int brightness; - /* Maximal value for brightness (read-only) */ + + /** + * @max_brightness: The maximum brightness value. + * + * This value must be set in the backlight_properties passed to + * devm_backlight_device_register() and shall not be modified by the + * driver after registration. + */ int max_brightness; - /* Current FB Power mode (0: full on, 1..3: power saving - modes; 4: full off), see FB_BLANK_XXX */ + + /** + * @power: The current power mode. + * + * User space can configure the power mode using the sysfs + * attribute: /sys/class/backlight//bl_power + * When the power property is updated update_status() is called. + * + * The possible values are: (0: full on, 1 to 3: power saving + * modes; 4: full off), see FB_BLANK_XXX. + * + * When the backlight device is enabled @power is set + * to FB_BLANK_UNBLANK. When the backlight device is disabled + * @power is set to FB_BLANK_POWERDOWN. + */ int power; - /* FB Blanking active? (values as for power) */ - /* Due to be removed, please use (state & BL_CORE_FBBLANK) */ + + /** + * @fb_blank: The power state from the FBIOBLANK ioclt. + * + * When the FBIOBLANK ioctl is called @fb_blank is set to the + * blank parameter and the update_status() operation is called. + * + * When the backlight device is enabled @fb_blank is set + * to FB_BLANK_UNBLANK. When the backlight device is disabled + * @fb_blank is set to FB_BLANK_POWERDOWN. + * + * Backlight drivers should avoid using this property. It has been + * replaced by state & BL_CORE_FBLANK (although most drivers should + * use backlight_is_blank() as the preferred means to get the blank + * state). + * + * fb_blank is deprecated and will be removed. + */ int fb_blank; - /* Backlight type */ + + /** + * @type: The type of backlight supported. + * + * The backlight type allows userspace to make appropriate + * policy desicions based on the backlight type. + * + * This value must be set in the backlight_properties + * passed to devm_backlight_device_register(). + */ enum backlight_type type; - /* Flags used to signal drivers of state changes */ + + /** + * @state: The state of the backlight core. + * + * The state is a bitmask. BL_CORE_FBBLANK is set when the display + * is expected to be blank. BL_CORE_SUSPENDED is set when the + * driver is suspended. + * + * backlight drivers are excpected to use backlight_is_blank() + * in their update_status() operation rather than reading the + * state property. + * + * The state is maintained by the core and drivers may not modify it. + */ unsigned int state; - /* Type of the brightness scale (linear, non-linear, ...) */ - enum backlight_scale scale; #define BL_CORE_SUSPENDED (1 << 0) /* backlight is suspended */ #define BL_CORE_FBBLANK (1 << 1) /* backlight is under an fb blank event */ + /** + * @scale: The type of the brightness scale. + */ + enum backlight_scale scale; }; struct backlight_device {