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 CADC8EB64DD for ; Wed, 5 Jul 2023 10:34:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231791AbjGEKeA (ORCPT ); Wed, 5 Jul 2023 06:34:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50464 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231334AbjGEKd4 (ORCPT ); Wed, 5 Jul 2023 06:33:56 -0400 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 CF0F6E6D for ; Wed, 5 Jul 2023 03:33:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1688553195; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=0pedzrxF76VGYnCdMLq3tBfEt7kLCHpedkXjqiqZXI8=; b=CKFw4ZfkGPtBIu9Br2AQJM0DVn12XKkjU7340CUNgE3s/w2yi59lHuUZDpHCrTw2BZX3NQ wy6orwny8oy3RWrtGVMRIU0/iSnMzL5QUoWgB1hBqwfC2x4ochA0vA1yuylmKVLbtCcuA5 Ih2I6LIbrcivgT5uC2XdDDEiDTLKAWo= Received: from mail-ej1-f69.google.com (mail-ej1-f69.google.com [209.85.218.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-662-Q5bexCRbMpGhyfVSQ886zA-1; Wed, 05 Jul 2023 06:33:11 -0400 X-MC-Unique: Q5bexCRbMpGhyfVSQ886zA-1 Received: by mail-ej1-f69.google.com with SMTP id a640c23a62f3a-992e6840901so76196966b.0 for ; Wed, 05 Jul 2023 03:33:10 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1688553190; x=1691145190; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=0pedzrxF76VGYnCdMLq3tBfEt7kLCHpedkXjqiqZXI8=; b=YN0gwQmdZdF+KeSLRqjnw3Vn41igBn4anCZE6BN94r6jqvgZg56b4Wgq8CtO+NId+5 YRUn3Hfgs0qoJWSMiEZNwglG5fdbAa36lhvD/GIex3D8CCxyt+bco1500jczFCOf6FYw z7XY3HFUjyMzVu6dHEwnHVj5VQWtpWX2ind2z3Y+LjK/fmnFk9vSsBz3Cbqze+Txvj03 I623iRVbKKuSzRBu7UN92IHNPZ0VbgsowzsaorHcMCKRNnZKq5NOk4KCBxoezafWer1g QojKpJ9RiFXhdFsCT0IYZrSnlN4x3b6fEYEteaaihIASDS4wLW5E5VBhK3Qb72xzbIIX ljmQ== X-Gm-Message-State: ABy/qLbu6b2EnOo3e1AKX8wzYDyKOD7R+y90WNsXtunycVks9psbm/4P PqmFWX9Akc7PSrXrkpJjOA4u3n5sg9OKAOcXl8RAk9LwZr6YNPwxih6SA5slDQtFfPK+hMgpfJn HCCmtKF4HpZdow0WNZWDmRnOJ X-Received: by 2002:a17:907:2d93:b0:986:38ab:ef99 with SMTP id gt19-20020a1709072d9300b0098638abef99mr1967400ejc.9.1688553189925; Wed, 05 Jul 2023 03:33:09 -0700 (PDT) X-Google-Smtp-Source: APBJJlGhXqePR6/QEYX86GFSnxBLHxWyQyo9uA2HI7qOIKMEJ/tQuS5Enp3k+Ifdbo8yVpukIpwMvw== X-Received: by 2002:a17:907:2d93:b0:986:38ab:ef99 with SMTP id gt19-20020a1709072d9300b0098638abef99mr1967382ejc.9.1688553189676; Wed, 05 Jul 2023 03:33:09 -0700 (PDT) Received: from ?IPV6:2001:1c00:c32:7800:5bfa:a036:83f0:f9ec? (2001-1c00-0c32-7800-5bfa-a036-83f0-f9ec.cable.dynamic.v6.ziggo.nl. [2001:1c00:c32:7800:5bfa:a036:83f0:f9ec]) by smtp.gmail.com with ESMTPSA id z2-20020a50eb42000000b0051bf17d7710sm12908012edp.57.2023.07.05.03.33.08 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 05 Jul 2023 03:33:09 -0700 (PDT) Message-ID: Date: Wed, 5 Jul 2023 12:33:08 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.12.0 Subject: Re: [PATCH] ACPI: video: Invoke _PS0 at boot for ACPI video To: "Rafael J. Wysocki" , Kai-Heng Feng Cc: lenb@kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org References: <20230704074506.2304939-1-kai.heng.feng@canonical.com> Content-Language: en-US, nl From: Hans de Goede In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 7/4/23 18:58, Rafael J. Wysocki wrote: > On Tue, Jul 4, 2023 at 9:46 AM Kai-Heng Feng > wrote: >> >> Screen brightness can only be changed once on some HP laptops. >> >> Vendor identified the root cause as Linux doesn't invoke _PS0 at boot >> for all ACPI devices: > > This part of the changelog is confusing, because the evaluation of > _PS0 is not a separate operation. _PS0 gets evaluated when devices > undergo transitions from low-power states to D0. > >> Scope (\_SB.PC00.GFX0) >> { >> Scope (DD1F) >> { >> Method (_PS0, 0, Serialized) // _PS0: Power State 0 >> { >> If (CondRefOf (\_SB.PC00.LPCB.EC0.SSBC)) >> { >> \_SB.PC00.LPCB.EC0.SSBC () >> } >> } >> ... >> } >> ... >> } >> >> _PS0 doesn't get invoked for all ACPI devices because of commit >> 7cd8407d53ef ("ACPI / PM: Do not execute _PS0 for devices without _PSC >> during initialization"). So this _PS0 which seems to be the one which needs to run here, is not the _PS0 for the GFX0 ACPI device, but rather for a child ACPI device-node which describes the connector (assumed based on the small part of quoted DSDT, the actual definition of the DD1F device-node is missing). Having a _PS0 method on a connector object is really weird IMHO. But if we need to invoke such a _PS0 method then IMHO that really should be done in the drm/kms driver. E.g. at least the i915 code already contains code to map the ACPI connector objects to the drm_connector objects, so it should be relatively easily to make that try and do a power-transition to D0 when enabling the connector. Also can you provide some more info on the hw on which this is being seen: 1. What GPU(s) is/are being used 2. If there is a mux for hybrid gfx in which mode is the mux set ? 3. Wjich method is used to control the brightness (which backlight-class-devices show up under /sys/class/backlight) ? And can you add this info to the commit msg for the next version of the patch ? Regards, Hans > > And yes, Linux doesn't put all of the ACPI devices into D0 during > initialization, but the above commit has a little to do with that. > >> For now explicitly call _PS0 for ACPI video to workaround the issue. > > This is not what the patch is doing. > >> Signed-off-by: Kai-Heng Feng >> --- >> drivers/acpi/acpi_video.c | 2 ++ >> 1 file changed, 2 insertions(+) >> >> diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c >> index 62f4364e4460..793259bd18c8 100644 >> --- a/drivers/acpi/acpi_video.c >> +++ b/drivers/acpi/acpi_video.c >> @@ -2027,6 +2027,8 @@ static int acpi_video_bus_add(struct acpi_device *device) >> if (error) >> goto err_put_video; >> >> + acpi_device_fix_up_power_extended(device); >> + > > I would like to know what Hans thinks about this. > >> pr_info("%s [%s] (multi-head: %s rom: %s post: %s)\n", >> ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device), >> video->flags.multihead ? "yes" : "no", >> -- >