From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vinod Koul Subject: Re: [RFC 00/10] Enable HDA Codec support on Intel Platforms (Series2) Date: Mon, 4 Dec 2017 08:52:30 +0530 Message-ID: <20171204032229.GZ32417@localhost> References: <1512119648-2700-1-git-send-email-rakesh.a.ughreja@intel.com> <23319967-3571-9e8c-3077-94200bff813f@linux.intel.com> <20171203172037.GS32417@localhost> <780726ad-3587-1f05-89e4-800ad8ce7375@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by alsa0.perex.cz (Postfix) with ESMTP id E52CE26710B for ; Mon, 4 Dec 2017 04:18:55 +0100 (CET) Content-Disposition: inline In-Reply-To: <780726ad-3587-1f05-89e4-800ad8ce7375@linux.intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Pierre-Louis Bossart Cc: alsa-devel@alsa-project.org, Takashi Iwai , liam.r.girdwood@linux.intel.com, patches.audio@intel.com, broonie@kernel.org, Rakesh Ughreja List-Id: alsa-devel@alsa-project.org On Sun, Dec 03, 2017 at 09:15:21PM -0600, Pierre-Louis Bossart wrote: > On 12/3/17 11:20 AM, Vinod Koul wrote: > >On Fri, Dec 01, 2017 at 09:03:25PM +0100, Takashi Iwai wrote: > >>>>>FIXME: > >>>>>- KConfig changes does not look right, but I could not think of any proper > >>>>> way without making changes into legacy HDA codec driver. So need some > >>>>> help on this topic. > >>>> > >>>>And this is another big issue. As long as you don't allow build both, > >>>>it never flies with distros, and it means no dramatic improvement of > >>>>the situation, either. > >>>> > >>>>IOW, we have to make the codec driver working on both controller/bus > >>>>implementations, and it essentially means to rewrite the HD-audio > >>>>codec plumbing code. Currently, it's a kind of half-baked state, and > >>>>we need to cast to unified form. > >>> > >>>Before going into codec support, should we first deal with the > >>>selection of the ASoC/Legacy mode for the controller side of things? > >>>Even with basic HDMI/iDisp cases, we don't have a clean solution > >>>today. When I worked on the late Joule platform, there was no fallback > >>>mode which forced a recompilation depending on BIOS settings. > >>>My understanding is that there is no support for multiple drivers > >>>registering for the same PCI ID, I believe we'll have to define a > >>>top-level wrapper which arbitrates internally based on BIOS settings > >>>and user/distro preferences which mode is selected. > >> > >>True, we need to sort out that. But the selection of the card-level > >>driver can be relatively easily done in a manual way, either via > >>blacklisting or by common module options. Currently AMDGPU and radeon > >>drivers are in such situation, for example. > >> > >>A common single switch, or at best the automatic arbitration would be > >>preferred, of course, though. > > > >The switch is again short term as we should progress and move towards one > >solution whilst deprecating the other, so that way this makes a simple > >solution and helps in transition, change flag defaults and deprecate. > > Sorry, I don't get your point. Are you saying the legacy would be > deprecated? that was never my understanding, Rakesh's patches only make it > easier to use the DSP in combination with an HDaudio codec, but if the DSP > is not present the legacy is the fallback, no? for now yes, but what prevents us from supporting coupled mode when DSP is disabled :) -- ~Vinod