From patchwork Thu Dec 15 09:41:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 634518 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 18CB9C4332F for ; Thu, 15 Dec 2022 09:42:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229592AbiLOJmc (ORCPT ); Thu, 15 Dec 2022 04:42:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43566 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229854AbiLOJma (ORCPT ); Thu, 15 Dec 2022 04:42:30 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1CCE82BF2 for ; Thu, 15 Dec 2022 01:41:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1671097309; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=1BG7uuSnGPV79muqIARaa573ojSEFReXOVoQVHexFwI=; b=XfZID8WCsjc6V5lUaOh5pGf47lmHybYQscnMJn/Ikao1wbXlsOdrtkl6fZZKVPW0V7AjoL IZ7hnjngC7j6a0sKUjVMeZZAG67wF9A2DQqbDWcNoES/OPIeiI8y7EgP8G/IJetMJGvrl4 ZRlHM9vuZDNzCh/2eKR9Ov99dxKL5Zw= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-372-CTPDtuV8OTOv598Mvja6Hg-1; Thu, 15 Dec 2022 04:41:47 -0500 X-MC-Unique: CTPDtuV8OTOv598Mvja6Hg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id E3C8886C14C; Thu, 15 Dec 2022 09:41:46 +0000 (UTC) Received: from localhost.localdomain (unknown [10.39.193.128]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1860B14171BE; Thu, 15 Dec 2022 09:41:45 +0000 (UTC) From: Hans de Goede To: "Rafael J . Wysocki" Cc: Hans de Goede , linux-acpi@vger.kernel.org, platform-driver-x86@vger.kernel.org, Aditya Garg Subject: [PATCH] ACPI: video: Fix Apple GMUX backlight detection Date: Thu, 15 Dec 2022 10:41:38 +0100 Message-Id: <20221215094138.7120-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org 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 --- 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 a934bbc9dd37..1b78c7434492 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) @@ -767,7 +788,7 @@ 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; /* Use ACPI video if available, except when native should be preferred. */