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 D7AC3C5479D for ; Mon, 2 Jan 2023 11:27:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232807AbjABL1X (ORCPT ); Mon, 2 Jan 2023 06:27:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45948 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232740AbjABL0r (ORCPT ); Mon, 2 Jan 2023 06:26:47 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B74F7655D for ; Mon, 2 Jan 2023 03:25:22 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 6397660F37 for ; Mon, 2 Jan 2023 11:25:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 775ABC433EF; Mon, 2 Jan 2023 11:25:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672658721; bh=OJxtv8Lu4/H79MRZceI+ffMKtRC/yFWX/+WKxj2GxG4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BOmomBraq45X3edF+YeRvWNrCYjlgm+xVCdhfmKYOlpHURPZNbyOark5mScHqdWf8 ootNw57mAsFedHx4/2bwey/Pgg0e5jg3JjCf3KZ7s4Etu36ipaF0N4R6W8o6rIVtxC 60GX1fG+6fgyOPIm7LpO3msw/+vFo8keeMSRPSc0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hans de Goede , "Rafael J. Wysocki" , Sasha Levin , Aditya Garg Subject: [PATCH 6.1 10/71] ACPI: video: Fix Apple GMUX backlight detection Date: Mon, 2 Jan 2023 12:21:35 +0100 Message-Id: <20230102110551.907189699@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230102110551.509937186@linuxfoundation.org> References: <20230102110551.509937186@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Hans de Goede [ Upstream commit 3cf3b7f012f3ea8bdc56196e367cf07c10424855 ] The apple-gmux driver only binds to old GMUX devices which have an IORESOURCE_IO resource (using inb()/outb()) rather then memory-mapped IO (IORESOURCE_MEM). T2 MacBooks use the new style GMUX devices (with IORESOURCE_MEM access), so these are not supported by the apple-gmux driver. This is not a problem since they have working ACPI video backlight support. But the apple_gmux_present() helper only checks if an ACPI device with the "APP000B" HID is present, causing acpi_video_get_backlight_type() to return acpi_backlight_apple_gmux disabling the acpi_video backlight device. Add a new apple_gmux_backlight_present() helper which checks that the "APP000B" device actually is an old GMUX device with an IORESOURCE_IO resource. This fixes the acpi_video0 backlight no longer registering on T2 MacBooks. Note people are working to add support for the new style GMUX to Linux: https://github.com/kekrby/linux-t2/commits/wip/hybrid-graphics Once this lands this patch should be reverted so that acpi_video_get_backlight_type() also prefers the gmux on new style GMUX MacBooks, but for now this is necessary to avoid regressing backlight control on T2 Macs. Fixes: 21245df307cb ("ACPI: video: Add Apple GMUX brightness control detection") Reported-and-tested-by: Aditya Garg Signed-off-by: Hans de Goede Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/acpi/video_detect.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index ffa19d418847..13f10fbcd7f0 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -34,6 +34,7 @@ #include #include #include +#include #include #include #include @@ -105,6 +106,26 @@ static bool nvidia_wmi_ec_supported(void) } #endif +static bool apple_gmux_backlight_present(void) +{ + struct acpi_device *adev; + struct device *dev; + + adev = acpi_dev_get_first_match_dev(GMUX_ACPI_HID, NULL, -1); + if (!adev) + return false; + + dev = acpi_get_first_physical_node(adev); + if (!dev) + return false; + + /* + * drivers/platform/x86/apple-gmux.c only supports old style + * Apple GMUX with an IO-resource. + */ + return pnp_get_resource(to_pnp_dev(dev), IORESOURCE_IO, 0) != NULL; +} + /* Force to use vendor driver when the ACPI device is known to be * buggy */ static int video_detect_force_vendor(const struct dmi_system_id *d) @@ -755,7 +776,7 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native) if (nvidia_wmi_ec_present) return acpi_backlight_nvidia_wmi_ec; - if (apple_gmux_present()) + if (apple_gmux_backlight_present()) return acpi_backlight_apple_gmux; /* Chromebooks should always prefer native backlight control. */ -- 2.35.1