From patchwork Wed Sep 18 12:42:58 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kai-Heng Feng X-Patchwork-Id: 11150279 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9D674912 for ; Wed, 18 Sep 2019 12:43:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8512220665 for ; Wed, 18 Sep 2019 12:43:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727283AbfIRMnF (ORCPT ); Wed, 18 Sep 2019 08:43:05 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:50430 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725902AbfIRMnF (ORCPT ); Wed, 18 Sep 2019 08:43:05 -0400 Received: from 61-220-137-37.hinet-ip.hinet.net ([61.220.137.37] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1iAZIU-00079V-MC; Wed, 18 Sep 2019 12:43:03 +0000 From: Kai-Heng Feng To: bhelgaas@google.com, tiwai@suse.com Cc: linux-pci@vger.kernel.org, alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, Kai-Heng Feng Subject: [PATCH v3 2/2] ALSA: hda: Allow HDA to be runtime suspended when dGPU is not bound to a driver Date: Wed, 18 Sep 2019 20:42:58 +0800 Message-Id: <20190918124258.10744-1-kai.heng.feng@canonical.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190828180128.1732-1-kai.heng.feng@canonical.com> References: <20190828180128.1732-1-kai.heng.feng@canonical.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Nvidia proprietary driver doesn't support runtime power management, so when a user only wants to use the integrated GPU, it's a common practice to let dGPU not to bind any driver, and let its upstream port to be runtime suspended. At the end of runtime suspension the port uses platform power management to disable power through _OFF method of power resource, which is listed by _PR3. After commit b516ea586d71 ("PCI: Enable NVIDIA HDA controllers"), when the dGPU comes with an HDA function, the HDA won't be suspended if the dGPU is unbound, so the power resource can't be turned off by its upstream port driver. Commit 37a3a98ef601 ("ALSA: hda - Enable runtime PM only for discrete GPU") only allows HDA to be runtime suspended once GPU is bound, to keep APU's HDA working. However, HDA on dGPU isn't that useful if dGPU is not bound to any driver. So let's relax the runtime suspend requirement for dGPU's HDA function, to disable the power source to save lots of power. BugLink: https://bugs.launchpad.net/bugs/1840835 Fixes: b516ea586d71 ("PCI: Enable NVIDIA HDA controllers") Signed-off-by: Kai-Heng Feng --- v3: - Make changelog more clear. v2: - Change wording. - Rebase to Tiwai's branch. sound/pci/hda/hda_intel.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c index 91e71be42fa4..c3654d22795a 100644 --- a/sound/pci/hda/hda_intel.c +++ b/sound/pci/hda/hda_intel.c @@ -1284,7 +1284,11 @@ static void init_vga_switcheroo(struct azx *chip) dev_info(chip->card->dev, "Handle vga_switcheroo audio client\n"); hda->use_vga_switcheroo = 1; - chip->bus.keep_power = 1; /* cleared in either gpu_bound op or codec probe */ + + /* cleared in either gpu_bound op or codec probe, or when its + * root port has _PR3 (i.e. dGPU). + */ + chip->bus.keep_power = !pci_pr3_present(p); chip->driver_caps |= AZX_DCAPS_PM_RUNTIME; pci_dev_put(p); }