From patchwork Tue May 17 15:23:29 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: 12852662 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 0DB62C433F5 for ; Tue, 17 May 2022 15:24:54 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BD530112F62; Tue, 17 May 2022 15:24:35 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by gabe.freedesktop.org (Postfix) with ESMTPS id A5C6810EE1C for ; Tue, 17 May 2022 15:24:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1652801069; 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: in-reply-to:in-reply-to:references:references; bh=t+H/TswPkMRXO5vBRUWnPMtn4ad0PJrC+rqLbyxYlrs=; b=bSKSND4MZ88uaC4TT5uphmdoFO5vhKQExd4HMgNELRMvhtUFpgMbjz3LcOnp/LnHSD+66S 7/sHNhOhVxV1OhEVMKDhSDbPi7xsUmQCBotg/Gk6kR1LCXmh7wjfV8QCmdUlHKCAwldVHz 0nPAv/XMNv5PYSIXxKaqLCRWr2Loepg= 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-393-Lq3kuABZNsiv6QA1BZU6Qw-1; Tue, 17 May 2022 11:24:26 -0400 X-MC-Unique: Lq3kuABZNsiv6QA1BZU6Qw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 21EF4101A52C; Tue, 17 May 2022 15:24:25 +0000 (UTC) Received: from localhost.localdomain (unknown [10.39.192.162]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8F58EC15D75; Tue, 17 May 2022 15:24:21 +0000 (UTC) From: Hans de Goede To: Ben Skeggs , Karol Herbst , Lyude , Daniel Dadap , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , Tvrtko Ursulin , Alex Deucher , =?utf-8?q?Christian_K=C3=B6nig?= , Pan@freedesktop.org, Xinhui , "Rafael J . Wysocki" , Mika Westerberg , Mark Gross , Andy Shevchenko Subject: [PATCH 12/14] drm/nouveau: Register ACPI video backlight when nv_backlight registration fails Date: Tue, 17 May 2022 17:23:29 +0200 Message-Id: <20220517152331.16217-13-hdegoede@redhat.com> In-Reply-To: <20220517152331.16217-1-hdegoede@redhat.com> References: <20220517152331.16217-1-hdegoede@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.8 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-acpi@vger.kernel.org, David Airlie , nouveau@lists.freedesktop.org, intel-gfx , dri-devel@lists.freedesktop.org, platform-driver-x86@vger.kernel.org, Hans de Goede , amd-gfx@lists.freedesktop.org, Len Brown Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Typically the acpi_video driver will initialize before nouveau, which used to cause /sys/class/backlight/acpi_video0 to get registered and then nouveau would register its own nv_backlight device later. After which the drivers/acpi/video_detect.c code unregistered the acpi_video0 device to avoid there being 2 backlight devices. This means that userspace used to briefly see 2 devices and the disappearing of acpi_video0 after a brief time confuses the systemd backlight level save/restore code, see e.g.: https://bbs.archlinux.org/viewtopic.php?id=269920 To fix this the ACPI video code has been modified to make backlight class device registration a separate step, relying on the drm/kms driver to ask for the acpi_video backlight registration after it is done setting up its native backlight device. Add a call to the new acpi_video_register_backlight() when native backlight device registration has failed / was skipped to ensure that there is a backlight device available before the drm_device gets registered with userspace. Signed-off-by: Hans de Goede Reviewed-by: Lyude Paul --- drivers/gpu/drm/nouveau/nouveau_backlight.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/nouveau/nouveau_backlight.c b/drivers/gpu/drm/nouveau/nouveau_backlight.c index f56ff797c78c..0ae8793357a4 100644 --- a/drivers/gpu/drm/nouveau/nouveau_backlight.c +++ b/drivers/gpu/drm/nouveau/nouveau_backlight.c @@ -436,6 +436,13 @@ nouveau_backlight_init(struct drm_connector *connector) fail_alloc: kfree(bl); + /* + * If we get here we have an internal panel, but no nv_backlight, + * try registering an ACPI video backlight device instead. + */ + if (ret == 0) + acpi_video_register_backlight(); + return ret; }