From patchwork Sun May 17 19:01:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sam Ravnborg X-Patchwork-Id: 189105 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=-9.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 81B8CC433DF for ; Sun, 17 May 2020 19:02:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5B97E207D3 for ; Sun, 17 May 2020 19:02:00 +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="CPPI6Nv0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726591AbgEQTCA (ORCPT ); Sun, 17 May 2020 15:02:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45520 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726269AbgEQTB7 (ORCPT ); Sun, 17 May 2020 15:01:59 -0400 Received: from mail-lf1-x141.google.com (mail-lf1-x141.google.com [IPv6:2a00:1450:4864:20::141]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5334DC061A0C; Sun, 17 May 2020 12:01:59 -0700 (PDT) Received: by mail-lf1-x141.google.com with SMTP id 82so6130485lfh.2; Sun, 17 May 2020 12:01:59 -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=XV8ji1IDXAzgoqiTjEkmwRFdCjcd4KoRPZRb8vwPSkM=; b=CPPI6Nv0NmK6Jgf2qWm7LYYc+OuCbj2lFpHs1PWenFVqPIVubsIY83GZvYfeDuppos UkKB3SeT6wmalj7wHr0oN6C1ufkJOkyXOcJqgi8JvXafMrk3IxyVYUBqxIQpxz8M1BRu m8uCTaCRadc6URt5l2kNGHcofVYu/BUShyR2qfoPk/5F4JHzLNg2Hy9fS7252RoAuqYv mAvgo0uEuHFzYcTcs6oom0VuAihNXBJ7jfkOIP555X56lPxO72xF3KeO2fxuRVY6QiHH qzbbyIMyEa1FaULMciY+6rD5k6LCqb1L9z4LhPk6eQmA3GTSvgWlPfUZ1OSAt8aimkDl P/FQ== 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=XV8ji1IDXAzgoqiTjEkmwRFdCjcd4KoRPZRb8vwPSkM=; b=G0ATi/zZ6HNqZrutTC6XnVfieidB5ybFvrExc5ZkBwGtSqybiA9JbddyVhSRR38Cw6 TNv5ulRvEZKCrsbIN4j10cbdHTTZMR40sdona5XlS471IgIM0iypVIhCqLhCqX45U8H6 PEki9q8G45KmtsKaJwyeani3T9EGFzV0MfMDJunoCyCf/9yyztYVXl/3Hb8lmwYSKIAU K3L0kqBrqzutC6OyrQEsbd8Yr5t0vMCgEFjGIiQRIuZkewWvrmxzaFt1RV5sPacalV/e dE5BuD4Zd5L3n7kkit68ggloe9gZiUpW6E77QfTeQOIjOpcaQQPMikcK4X132S2Z8ny7 JTOg== X-Gm-Message-State: AOAM531MN+zZwIQ+v1tSpKOa5yY5IjYa/8jXh9JFbX987h96xYfA6NOz GLdIYqIxkveS5OxDHOGxHgQ= X-Google-Smtp-Source: ABdhPJxELt7Vi9287IQwgCidWZHrUTSvjwrWfyZWE3Fzz5jgr5WONsYAndwhLNaQsrNw5sDoIgf/1g== X-Received: by 2002:a05:6512:3384:: with SMTP id h4mr9221349lfg.150.1589742117777; Sun, 17 May 2020 12:01:57 -0700 (PDT) Received: from saturn.lan ([2a00:fd00:805f:db00:5d55:b3eb:397b:9086]) by smtp.gmail.com with ESMTPSA id t20sm3282535lfl.17.2020.05.17.12.01.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 17 May 2020 12:01:57 -0700 (PDT) From: Sam Ravnborg To: dri-devel@lists.freedesktop.org, Jingoo Han , Lee Jones , Daniel Thompson , Peter Ujfalusi , Tomi Valkeinen Cc: Andy Gross , Bartlomiej Zolnierkiewicz , Bjorn Andersson , Daniel Vetter , David Airlie , Douglas Anderson , Jani Nikula , Jonathan Corbet , Linus Walleij , linux-arm-msm@vger.kernel.org, linux-pwm@vger.kernel.org, Maarten Lankhorst , Maxime Ripard , Michael Hennerich , patches@opensource.cirrus.com, Russell King , Sam Ravnborg , Support Opensource , Thierry Reding , Thomas Zimmermann , Uwe Kleine-Konig Subject: [PATCH v2 04/16] backlight: improve backlight_ops documentation Date: Sun, 17 May 2020 21:01:27 +0200 Message-Id: <20200517190139.740249-5-sam@ravnborg.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200517190139.740249-1-sam@ravnborg.org> References: <20200517190139.740249-1-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 Improve the documentation for backlight_ops and adapt it to kernel-doc style. Signed-off-by: Sam Ravnborg Cc: Lee Jones Cc: Daniel Thompson Cc: Jingoo Han Reviewed-by: Daniel Thompson --- include/linux/backlight.h | 60 +++++++++++++++++++++++++++++++++++---- 1 file changed, 54 insertions(+), 6 deletions(-) diff --git a/include/linux/backlight.h b/include/linux/backlight.h index a0a083b35c47..519dc61ce7e4 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -55,19 +55,67 @@ enum backlight_scale { struct backlight_device; struct fb_info; +/** + * struct backlight_ops - backlight operations + * + * The backlight operations are specifed when the backlight device is registered. + */ struct backlight_ops { + /** + * @options: + * + * The options parameter is used to adjust the behaviour of the core. + * Set BL_CORE_SUSPENDRESUME to get the update_status() operation called + * upon suspend and resume. + */ unsigned int options; #define BL_CORE_SUSPENDRESUME (1 << 0) - /* Notify the backlight driver some property has changed */ + /** + * @update_status: + * + * Notify the backlight driver some property has changed. + * The update_status operation is protected by the update_lock. + * + * The backlight driver is expected to use backlight_is_blank() + * to check if the display is blanked and set brightness accordingly. + * update_status() is called when any of the properties has changed. + * + * RETURNS: + * + * 0 on sucees, negative error code if any failure occured. + */ int (*update_status)(struct backlight_device *); - /* Return the current backlight brightness (accounting for power, - fb_blank etc.) */ + + /** + * @get_brightness: + * + * Return the current backlight brightness. + * The driver may implement this as a readback from the HW. + * This operation is optional and if not present then the current brightness + * property value is used. + * + * RETURNS: + * + * A brightness value which is 0 or a positive numer. + * On failure a negative error code is returned. + */ int (*get_brightness)(struct backlight_device *); - /* Check if given framebuffer device is the one bound to this backlight; - return 0 if not, !=0 if it is. If NULL, backlight always matches the fb. */ - int (*check_fb)(struct backlight_device *, struct fb_info *); + + /** + * @check_fb: + * + * Check if given framebuffer device is the one bound to this backlight. + * This operation is optional and if not implemented it is assumed that the + * fbdev is always the one bound to the backlight. + * + * RETURNS: + * + * If info is NULL or the info matches the fbdev bound to the backlight return true. + * If info does not match the fbdev bound to the backlight return false. + */ + int (*check_fb)(struct backlight_device *bd, struct fb_info *info); }; /* This structure defines all the properties of a backlight */