From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751205AbeCIJeh (ORCPT ); Fri, 9 Mar 2018 04:34:37 -0500 Received: from esa3.dell-outbound.iphmx.com ([68.232.153.94]:59587 "EHLO esa3.dell-outbound.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751167AbeCIJef (ORCPT ); Fri, 9 Mar 2018 04:34:35 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: =?us-ascii?q?A2FjAADUU6Jah8qZ6EReGQEBAQEBAQEBA?= =?us-ascii?q?QEBAQcBAQEBAYQmfygKg0aKHo13ggKBFocejQyCFQqFJQIagnUhNBgBAgEBAQE?= =?us-ascii?q?BAQIBAhABAQEIDQkIKC6COCKCSgEBAQEDIwQNOgsMBAIBCBEBAwEBAQICHwQDA?= =?us-ascii?q?gICHyUBAgEFCAIEAQ0FCIR5AxWsQYFsOocqDYEwghqBDoQogi6DPIMtgmqCJRk?= =?us-ascii?q?QIQKCT4JiBI1/jCUxCY0ygy2Oa4oyhxWBLB6CC3BPgkOCMRAMFoFldwGIQyqBB?= =?us-ascii?q?4EXAQEB?= X-IPAS-Result: =?us-ascii?q?A2FjAADUU6Jah8qZ6EReGQEBAQEBAQEBAQEBAQcBAQEBAYQ?= =?us-ascii?q?mfygKg0aKHo13ggKBFocejQyCFQqFJQIagnUhNBgBAgEBAQEBAQIBAhABAQEID?= =?us-ascii?q?QkIKC6COCKCSgEBAQEDIwQNOgsMBAIBCBEBAwEBAQICHwQDAgICHyUBAgEFCAI?= =?us-ascii?q?EAQ0FCIR5AxWsQYFsOocqDYEwghqBDoQogi6DPIMtgmqCJRkQIQKCT4JiBI1/j?= =?us-ascii?q?CUxCY0ygy2Oa4oyhxWBLB6CC3BPgkOCMRAMFoFldwGIQyqBB4EXAQEB?= From: X-LoopCount0: from 10.166.132.187 X-IronPort-AV: E=Sophos;i="5.47,444,1515477600"; d="scan'208";a="147432509" X-DLP: DLP_GlobalPCIDSS To: , CC: , , , , , , Subject: RE: [PATCH v2 3/3] ALSA: hda: Disabled unused audio controller for Dell platforms with Switchable Graphics Thread-Topic: [PATCH v2 3/3] ALSA: hda: Disabled unused audio controller for Dell platforms with Switchable Graphics Thread-Index: AQHTtr1XC+3UjKIddE2I55hGuXPKiaPIAceAgAAHyYD//5ufkA== Date: Fri, 9 Mar 2018 09:34:01 +0000 Message-ID: <014795f5a3014cd3bf55de26f76a5af8@ausx13mpc124.AMER.DELL.COM> References: <20180308091023.9061-1-kai.heng.feng@canonical.com> <20180308091023.9061-3-kai.heng.feng@canonical.com> <20180309090223.xb55ltac4pfesdrh@pali> <723DA929-C9FA-4F69-8D3A-03D8A75D09A6@canonical.com> In-Reply-To: <723DA929-C9FA-4F69-8D3A-03D8A75D09A6@canonical.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.143.242.75] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id w299YjuV021474 > -----Original Message----- > From: Kai Heng Feng [mailto:kai.heng.feng@canonical.com] > Sent: Friday, March 9, 2018 5:30 PM > To: Pali Rohár > Cc: mjg59@srcf.ucam.org; dvhart@infradead.org; andy@infradead.org; > Limonciello, Mario ; tiwai@suse.com; platform- > driver-x86@vger.kernel.org; Linux Kernel Mailing List kernel@vger.kernel.org>; alsa-devel@alsa-project.org > Subject: Re: [PATCH v2 3/3] ALSA: hda: Disabled unused audio controller for Dell > platforms with Switchable Graphics > > > > On Mar 9, 2018, at 5:02 PM, Pali Rohár wrote: > > > > On Thursday 08 March 2018 17:10:23 Kai-Heng Feng wrote: > >> Some Dell platforms (Preicsion 7510/7710/7520/7720) have a BIOS option > >> "Switchable Graphics" (SG). > >> > >> When SG is enabled, we have: > >> 00:02.0 VGA compatible controller: Intel Corporation Device 591b (rev 04) > >> 00:1f.3 Audio device: Intel Corporation CM238 HD Audio Controller (rev 31) > >> 01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. > >> [AMD/ATI] Ellesmere [Polaris10] > >> 01:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere > >> [Radeon RX 580] > >> > >> The Intel Audio outputs all the sound, including HDMI audio. The audio > >> controller comes with AMD graphics doesn't get used. > >> > >> When SG is disabled, we have: > >> 00:1f.3 Audio device: Intel Corporation CM238 HD Audio Controller (rev 31) > >> 01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. > >> [AMD/ATI] Ellesmere [Polaris10] > >> 01:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Ellesmere > >> [Radeon RX 580] > >> > >> Now it's a typical discrete-only system. HDMI audio comes from AMD audio > >> controller, others from Intel audio controller. > >> > >> When SG is enabled, the unused AMD audio controller still exposes its > >> sysfs, so userspace still opens the control file and stream. If > >> userspace tries to output sound through the stream, it hangs when > >> runtime suspend kicks in: > >> [ 12.796265] snd_hda_intel 0000:01:00.1: Disabling via vga_switcheroo > >> [ 12.796367] snd_hda_intel 0000:01:00.1: Cannot lock devices! > >> > >> Since the discrete audio controller isn't useful when SG enabled, we > >> should just disable the device. > >> > >> Signed-off-by: Kai-Heng Feng > >> --- > >> v2: Mario suggested to squash the HDA part into the same series. > >> > >> sound/pci/hda/hda_intel.c | 35 +++++++++++++++++++++++++++++++++++ > >> 1 file changed, 35 insertions(+) > >> > >> diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c > >> index 96143df19b21..8e3e8b88624a 100644 > >> --- a/sound/pci/hda/hda_intel.c > >> +++ b/sound/pci/hda/hda_intel.c > >> @@ -49,6 +49,7 @@ > >> #include > >> #include > >> #include > >> +#include > >> > >> #ifdef CONFIG_X86 > >> /* for snoop control */ > >> @@ -1620,6 +1621,35 @@ static void check_msi(struct azx *chip) > >> } > >> } > >> > >> +#if IS_ENABLED(CONFIG_DELL_LAPTOP) > >> +static bool check_dell_switchable_gfx(struct pci_dev *pdev) > >> +{ > >> + static int (*dell_switchable_gfx_enabled_func)(bool *); > >> + bool enabled; > >> + int err; > >> + > >> + if (pdev->vendor != PCI_VENDOR_ID_ATI || > >> + pdev->subsystem_vendor != PCI_VENDOR_ID_DELL) > >> + return false; > > > > Are you sure that you want to do this check unconditionally on all > > machines which have enabled CONFIG_DELL_LAPTOP? > > > > Subvendor ID_DELL for dell specific code is not suspicious, but ID_ATI > > is. What would happen if ATI vendor changes to NVIDIA or other which is > > not related to Dell? > > We only check it when it's both ATI and DELL, otherwise just return false? > > The platform does have a NVIDIA variant, but the discrete NVIDIA have a > audio controller, hence it doesn't have the issue. > The issue only happens to AMD/ATI configs with "Switchable Graphics" option. > Pali is your concern that this code for matching vendor/subsystem is running on non-Dell too? The only other recommendation I think that can be to restrict to matching Dell OEM strings in SMBIOS table, but I don't think that's any better than the matching for VID/SSVID. > > > > Interesting question would be, how handle this situation Windows? > > I don't know how this platform handles this on Windows, I guess we need > Mario to shed some lights here. Sorry I don't have this information to share. I don't think it's too useful here anyway though because Windows driver architecture is much different in this area.