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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5A74AC4361B for ; Wed, 16 Dec 2020 15:59:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 118F322283 for ; Wed, 16 Dec 2020 15:59:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726658AbgLPP7L (ORCPT ); Wed, 16 Dec 2020 10:59:11 -0500 Received: from mx2.suse.de ([195.135.220.15]:46120 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725957AbgLPP7L (ORCPT ); Wed, 16 Dec 2020 10:59:11 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id C7B6AAC7B; Wed, 16 Dec 2020 15:58:29 +0000 (UTC) Date: Wed, 16 Dec 2020 16:58:29 +0100 Message-ID: From: Takashi Iwai To: Kai-Heng Feng Cc: tiwai@suse.com, Jaroslav Kysela , Kai Vehmanen , Pierre-Louis Bossart , Alex Deucher , Mike Rapoport , "moderated list:SOUND" , open list Subject: Re: [PATCH v2] ALSA: hda: Continue to probe when codec probe fails In-Reply-To: References: <20201214060621.1102931-1-kai.heng.feng@canonical.com> <20201216124726.2842197-1-kai.heng.feng@canonical.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 16 Dec 2020 16:50:20 +0100, Kai-Heng Feng wrote: > > On Wed, Dec 16, 2020 at 11:41 PM Takashi Iwai wrote: > > > > On Wed, 16 Dec 2020 13:47:24 +0100, > > Kai-Heng Feng wrote: > > > > > > Similar to commit 9479e75fca37 ("ALSA: hda: Keep the controller > > > initialization even if no codecs found"), when codec probe fails, it > > > doesn't enable runtime suspend, and can prevent graphics card from > > > getting powered down: > > > [ 4.280991] snd_hda_intel 0000:01:00.1: no codecs initialized > > > > > > $ cat /sys/bus/pci/devices/0000:01:00.1/power/runtime_status > > > active > > > > > > So mark there's no codec and continue probing to let runtime PM to work. > > > > > > BugLink: https://bugs.launchpad.net/bugs/1907212 > > > Signed-off-by: Kai-Heng Feng > > > > Hm, but if the probe fails, doesn't it mean something really wrong? > > IOW, how does this situation happen? > > The HDA controller is forcely created by quirk_nvidia_hda(). So > probably there's really not an HDA controller. I still don't understand how non-zero codec_mask is passed. The non-zero codec_mask means that BIOS or whatever believes that HD-audio codecs are present and let HD-audio controller reporting the presence. What error did you get at probing? > > The usual no-codec state is for the devices that have a bogus HD-audio > > bus remaining while codecs aren't hooked or disabled by BIOS. For > > that, it makes to leave the controller driver and let it idle. But if > > you get really an error, it's something to fix there, not to just > > ignore in general. > > The best approach I can think of is to make current two steps probe > into one. So when probe fails, the driver won't bind to the device. > What's the reason behind the two steps approach? It's a sort of must, as the module loading is involved with binding with the codecs, as well as (optionally) request_firmware() invocation. Takashi