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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1C363C38A2D for ; Mon, 24 Oct 2022 11:38:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231184AbiJXLiY (ORCPT ); Mon, 24 Oct 2022 07:38:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50430 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230472AbiJXLhp (ORCPT ); Mon, 24 Oct 2022 07:37:45 -0400 Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [IPv6:2607:f8b0:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C624813CDB for ; Mon, 24 Oct 2022 04:37:32 -0700 (PDT) Received: by mail-pf1-x434.google.com with SMTP id e4so4797032pfl.2 for ; Mon, 24 Oct 2022 04:37:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=daynix-com.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=nh284RfbKTKjVZ53xc/BjYmJT2KbUvj6smXua/Y15lg=; b=wKxhR+PYREmRgVKkasTw0GfLrz2v/WYReVJQ30eu6x7i4eVQgdnhuAzGFkfXj43osX iAXkQ9aOTTvoovjS5IAKs+vGwyfg/3OtbGuKU/dCjSKPeCgfec8HUoDEQ74hMGKLlidw xopGpztVbn+H0pgQsRhyf7RQzg47xJ12vGdWkiLpV1wmLs/HSBYTp0CLCI3VpboZfYoK OVdGvVz64lio5FjIFDglJN+RSxy4l6GjXQ4rIatNLGAan07rIxYhnoljN8p8kyn4jRRy crr47iBoKn1Bk8Y506uKaUb06iRU9mYdDjzttWDNXRDmwZYfgtsJrKYIzOgRriRarrJF 6iww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=nh284RfbKTKjVZ53xc/BjYmJT2KbUvj6smXua/Y15lg=; b=hC87GNHB+aqBtCXDAN1G0gqCmfub/8p5jENoJ2EGF0fHZnpUIhOKVriaVpeUYqclas 2SSQZkq+Ydf7qVdcCQChppivCS1jzfCPYij6onp370NvmoZtDbFDnunIbG6bfO7/AbSs nhO18xdTV3MpuOgNli7WtfVbmY2pKDmSs2c2c63JdnPEyPxLfnbi4I0/VDVyPBQtKe4g AVUVJaNJ8N+QJbkOe5+XFcFZGSGNRBywOcbGhq2RTs6MyORuLsTYoEl7RKNDDKrZMgct asElVt6kVkATRu/AmMEMIvi2nFODNwo97HO4biASwsKwPc6h1inXIVasJHDXuFHWA0PN 7Hxw== X-Gm-Message-State: ACrzQf1DaW+dOR6/jOemsfL5RxuKg7zGMyvlMnudS28zdRdxO3ibbDDr fBI2FHE2vjcf6TcMdyoCi4/tNw== X-Google-Smtp-Source: AMsMyM5qFqNKIQCrH6nqN3yVGbGf1IzcRlrs4UvsvzXwRIAC8cYkTRMstnrFzu4g/FRXgW5McIN7zw== X-Received: by 2002:a05:6a00:114c:b0:528:2c7a:6302 with SMTP id b12-20020a056a00114c00b005282c7a6302mr33351690pfm.37.1666611349588; Mon, 24 Oct 2022 04:35:49 -0700 (PDT) Received: from fedora.flets-east.jp ([2400:4050:c360:8200:8ae8:3c4:c0da:7419]) by smtp.gmail.com with ESMTPSA id b8-20020a170903228800b001830ed575c3sm19475075plh.117.2022.10.24.04.35.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 24 Oct 2022 04:35:49 -0700 (PDT) From: Akihiko Odaki Cc: David Airlie , Daniel Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Jonathan Corbet , "Rafael J. Wysocki" , Len Brown , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , "Lee, Chun-Yi" , Hans de Goede , Mark Gross , Corentin Chary , Cezary Jackiewicz , Matthew Garrett , =?UTF-8?q?Pali=20Roh=C3=A1r?= , Jonathan Woithe , Ike Panhc , Daniel Dadap , Kenneth Chan , Mattia Dongili , Henrique de Moraes Holschuh , Azael Avalos , Lee Jones , Daniel Thompson , Jingoo Han , Helge Deller , Robert Moore , dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, intel-gfx@lists.freedesktop.org, platform-driver-x86@vger.kernel.org, acpi4asus-user@lists.sourceforge.net, ibm-acpi-devel@lists.sourceforge.net, linux-fbdev@vger.kernel.org, devel@acpica.org, Akihiko Odaki Subject: [PATCH 01/22] drm/i915/opregion: Improve backlight request condition Date: Mon, 24 Oct 2022 20:34:52 +0900 Message-Id: <20221024113513.5205-2-akihiko.odaki@daynix.com> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20221024113513.5205-1-akihiko.odaki@daynix.com> References: <20221024113513.5205-1-akihiko.odaki@daynix.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org asle_set_backlight() needs to accept backlight request only if the firmware controls the backlight. It used the following expression for this purpose: acpi_video_get_backlight_type() == acpi_backlight_native This expression works well in practice, but has two semantic problems. One is that it actually determines if a backlight device which directly modifies hardware registers ("native backlight") exists. It is possible that a device which does not have backlight at all incorrectly triggers asle_set_backlight(), and the expression does not cover such a case. Another problem is that acpi_video_get_backlight_type() always return acpi_backlight_vendor in reality if CONFIG_ACPI_VIDEO is unset. It means even its ability to determine the existence of native backlight is somewhat limited. This change introduces a new function backlight_device_non_raw_exists(), which returns if the firmware is controlling the backlight, and is always available if backlight support is enabled. Signed-off-by: Akihiko Odaki --- drivers/gpu/drm/i915/display/intel_opregion.c | 3 ++- drivers/video/backlight/backlight.c | 18 ++++++++++++++++++ include/linux/backlight.h | 1 + 3 files changed, 21 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/display/intel_opregion.c b/drivers/gpu/drm/i915/display/intel_opregion.c index caa07ef34f21..82ea02ab94c2 100644 --- a/drivers/gpu/drm/i915/display/intel_opregion.c +++ b/drivers/gpu/drm/i915/display/intel_opregion.c @@ -26,6 +26,7 @@ */ #include +#include #include #include #include @@ -467,7 +468,7 @@ static u32 asle_set_backlight(struct drm_i915_private *dev_priv, u32 bclp) drm_dbg(&dev_priv->drm, "bclp = 0x%08x\n", bclp); - if (acpi_video_get_backlight_type() == acpi_backlight_native) { + if (!backlight_device_non_raw_exists()) { drm_dbg_kms(&dev_priv->drm, "opregion backlight request ignored\n"); return 0; diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c index b788ff3d0f45..4f0ce463e250 100644 --- a/drivers/video/backlight/backlight.c +++ b/drivers/video/backlight/backlight.c @@ -516,6 +516,24 @@ struct backlight_device *backlight_device_get_by_name(const char *name) } EXPORT_SYMBOL(backlight_device_get_by_name); +bool backlight_device_non_raw_exists(void) +{ + bool found = false; + struct backlight_device *bd; + + mutex_lock(&backlight_dev_list_mutex); + list_for_each_entry(bd, &backlight_dev_list, entry) { + if (bd->props.type != BACKLIGHT_RAW) { + found = true; + break; + } + } + mutex_unlock(&backlight_dev_list_mutex); + + return found; +} +EXPORT_SYMBOL(backlight_device_non_raw_exists); + /* deprecated - use devm_backlight_device_unregister() */ void backlight_device_unregister(struct backlight_device *bd) { diff --git a/include/linux/backlight.h b/include/linux/backlight.h index 614653e07e3a..364ef6f99a9e 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -444,6 +444,7 @@ int backlight_register_notifier(struct notifier_block *nb); int backlight_unregister_notifier(struct notifier_block *nb); struct backlight_device *backlight_device_get_by_name(const char *name); struct backlight_device *backlight_device_get_by_type(enum backlight_type type); +bool backlight_device_non_raw_exists(void); int backlight_device_set_brightness(struct backlight_device *bd, unsigned long brightness); -- 2.37.3