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 6E1EECCA480 for ; Wed, 20 Jul 2022 16:53:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235271AbiGTQxt (ORCPT ); Wed, 20 Jul 2022 12:53:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53216 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235224AbiGTQxt (ORCPT ); Wed, 20 Jul 2022 12:53:49 -0400 Received: from mail-ed1-x52d.google.com (mail-ed1-x52d.google.com [IPv6:2a00:1450:4864:20::52d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C0E42691C1; Wed, 20 Jul 2022 09:53:47 -0700 (PDT) Received: by mail-ed1-x52d.google.com with SMTP id z22so11556406edd.6; Wed, 20 Jul 2022 09:53:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=UJ8S55elQG8rT6GpyiUvZTI+ZRSSMG/MOcad0kU1mxc=; b=fsHG/tQ4hTj8OchDkCs08gXQinTEKkqANQIVGZu5jhS2nxVa/dLXfRrEDvqcEGfXyE tnXR+ggv6i6pm67wO0K5naCIiAkIaL4iq3HB1owXFBR0TBO9DzEJXdAxdJcb04p4J5UC C/2QyHd765C3vFaqc7P0VNDqmLXJjwIFr1wcRQ0DsXydOh+QbfreWjQwOiBkUntg6s97 jok35PJYMERSzCG62ZArthSoxwphhsEDYj+EDK/txbYVipBhcAPS9EbYRhul40ZkknTo D1ejvE5QxUlXYgaGB8VSR7D63iFmwqvFDAxM2q7XZJlPdrK8SB2MjGWbM91DxYTn43Mq wviA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=UJ8S55elQG8rT6GpyiUvZTI+ZRSSMG/MOcad0kU1mxc=; b=5CaURZvRMUvqBhFladllmhGF7ZlVml/hTV89wq73G4oFoZYizHmf4/X3fdODRo26OU bV/yVSpwcCrT+VYfUhu37GE9Dph3BSuBCEuiRox+wn/8Ab9kWrYX/W7SEXL4jkydUIO1 xrr41YOXJma5DktUb28Gm6vs8KXUyBm5MilVrcd19kfbJNP2MgJC20CtgNvmP3IvKTmP z7nQzvcamv78DxbO9nl2L76H4G5uP5atVrEdXoJJFH6bPpK+mmmJsBiC/tcfOqU/mw5M ryKUv8BvNWxVbrv/5D0O2klJvQezm5z1I0FzGzFET7mN4QY0hhrWxuf0AgSGX8CWtFPA MQ1Q== X-Gm-Message-State: AJIora/vNBhepkYSvsxgEJhDJ4jUWdMbWtBRmKG+2Cb5Se49zOyki0pQ WUeLdV+I1PDUu0Vmw1S34Z/7+3eO1A+yn3U/X6I= X-Google-Smtp-Source: AGRyM1uB7u0FCxKz1D9dYX/QTZ94wPS45vrIR6JXhCAzgfaN+XvDpYj5HMov9bLxiYLAehJj1UyobwdKqbQoMfQbmHM= X-Received: by 2002:a05:6402:d0a:b0:437:f9a1:8493 with SMTP id eb10-20020a0564020d0a00b00437f9a18493mr52228238edb.226.1658336026370; Wed, 20 Jul 2022 09:53:46 -0700 (PDT) MIME-Version: 1.0 References: <20220712193910.439171-1-hdegoede@redhat.com> <20220712193910.439171-14-hdegoede@redhat.com> In-Reply-To: <20220712193910.439171-14-hdegoede@redhat.com> From: Alex Deucher Date: Wed, 20 Jul 2022 12:53:34 -0400 Message-ID: Subject: Re: [PATCH v2 13/29] drm/amdgpu: Register ACPI video backlight when skipping amdgpu backlight registration To: Hans de Goede Cc: 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 , Lukas Wunner , Mark Gross , Andy Shevchenko , linux-acpi@vger.kernel.org, David Airlie , nouveau@lists.freedesktop.org, intel-gfx , dri-devel@lists.freedesktop.org, platform-driver-x86@vger.kernel.org, amd-gfx@lists.freedesktop.org, Len Brown Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: platform-driver-x86@vger.kernel.org On Tue, Jul 12, 2022 at 3:40 PM Hans de Goede wrote: > > Typically the acpi_video driver will initialize before amdgpu, which > used to cause /sys/class/backlight/acpi_video0 to get registered and then > amdgpu would register its own amdgpu_bl# 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 amdgpu skips > registering its own backlight device because of either the firmware_flags > or the acpi_video_get_backlight_type() return value. This ensures that > if the acpi_video backlight device should be used, it will be available > before the amdgpu drm_device gets registered with userspace. > > Signed-off-by: Hans de Goede > --- > drivers/gpu/drm/amd/amdgpu/atombios_encoders.c | 9 +++++++-- > drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 ++ > 2 files changed, 9 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c b/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c > index abf209e36fca..45cd9268b426 100644 > --- a/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c > +++ b/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c > @@ -184,11 +184,11 @@ void amdgpu_atombios_encoder_init_backlight(struct amdgpu_encoder *amdgpu_encode > return; > > if (!(adev->mode_info.firmware_flags & ATOM_BIOS_INFO_BL_CONTROLLED_BY_GPU)) > - return; > + goto register_acpi_backlight; > > if (!acpi_video_backlight_use_native()) { > DRM_INFO("Skipping amdgpu atom DIG backlight registration\n"); > - return; > + goto register_acpi_backlight; > } > > pdata = kmalloc(sizeof(struct amdgpu_backlight_privdata), GFP_KERNEL); > @@ -225,6 +225,11 @@ void amdgpu_atombios_encoder_init_backlight(struct amdgpu_encoder *amdgpu_encode > error: > kfree(pdata); > return; > + > +register_acpi_backlight: > + /* Try registering an ACPI video backlight device instead. */ > + acpi_video_register_backlight(); > + return; Can drop the return here. Either way, Acked-by: Alex Deucher > } > > void > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c > index 3b03a95e59a8..a667e66a9842 100644 > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c > @@ -4054,6 +4054,8 @@ amdgpu_dm_register_backlight_device(struct amdgpu_display_manager *dm) > > if (!acpi_video_backlight_use_native()) { > DRM_INFO("Skipping amdgpu DM backlight registration\n"); > + /* Try registering an ACPI video backlight device instead. */ > + acpi_video_register_backlight(); > return; > } > > -- > 2.36.0 >