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 B81A6C43217 for ; Thu, 17 Nov 2022 11:37:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239539AbiKQLhJ (ORCPT ); Thu, 17 Nov 2022 06:37:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42062 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239495AbiKQLeO (ORCPT ); Thu, 17 Nov 2022 06:34:14 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1674E22501 for ; Thu, 17 Nov 2022 03:34:11 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A595861253 for ; Thu, 17 Nov 2022 11:34:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 90E73C433D7; Thu, 17 Nov 2022 11:34:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1668684850; bh=yMu6+GoFnl1mrIFFhTT3h7tPE+tEdM553AlyVAInMtU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=HdOniGdlwP8cyj9N71XQTfTLaJOTTLgOhFdmgU4B+ak6zjuXmZIs3qRCND30cYI5p LwUV6gPCiTQeVyEhetyAvPKo6HRrLedjPJdUZgIAj6VGVw1mLZPqTGIu1TIiXu/n15 Pt2dhgSARtYkngniM6kN5WdFRICtscNIcNoA8Xg7qiYJ2aZxqiw/EpylvUU10nncSU 1a9VXdp7zAIdtQpJoYcC6HOGQTUKYY0WihJ7mwYs4b5dYsP1OvoTiwEdu9QUQyxqQw QmEWDn1h+Rdam4Y0+fPyop0vK7uYuO4/S2C+pmoHRvKzC0ffcLyngND8Rl6X+E5HJT vJE2Kq4p/UaOg== Date: Thu, 17 Nov 2022 11:34:06 +0000 From: Mark Brown To: Dmitry Torokhov Cc: Liam Girdwood , linux-kernel@vger.kernel.org, alsa-devel@alsa-project.org Subject: Re: [PATCH 01/11] ASoC: ak5386: switch to using gpiod API Message-ID: References: <20221116053817.2929810-1-dmitry.torokhov@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="QM8UBU9P046DRTWO" Content-Disposition: inline In-Reply-To: X-Cookie: Ego sum ens omnipotens. Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --QM8UBU9P046DRTWO Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Nov 16, 2022 at 11:07:48AM -0800, Dmitry Torokhov wrote: > On Wed, Nov 16, 2022 at 10:36:27AM +0000, Mark Brown wrote: > > How are we ensuring that people have described signals as active > > low/high in existing DTs, and are we positive that the signal is > > described as active low for all devices? In particular if the > > signal is described as a reset signal then it's active high even > > if we want it low while the device is actually in use. > I have been going through in-kernel DTSes and adjusting ones that are > incorrect. For external ones I think we should take a pragmatic approach > and say that if driver has last non-mechanical update in 2014 and there > are no users submitted to mainline since then (as this one), then it is > highly unlikely that devices currently using this component/codec will > be updated to the 6.2+ kernel even if they are still in service. And if > this does happen the breakage will be immediately obvious as we'll keep > the codec in reset state. > But if you really want to I can add quirk(s) to gpiolib forcing this > line to be treated as active-low regardless of what specified in DTS. > This kind of negates benefit of going to gpiod though. That doesn't address the bit about checking that the device describes the signal as active low in hardware - it's assuming that the signal is described by the device as an active low reset and not for example as a shutdown signal. TBH I'm not thrilled about just randomly breaking ABI compatibility for neatness reasons, it's really not helping people take device tree ABI compatibility seriously. --QM8UBU9P046DRTWO Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmN2HC4ACgkQJNaLcl1U h9Dxfgf/ftYFUMW/ILTdWcqMEKVkYIa3+9VBKpQL0Aq9xN022wMz+ICsRHsAonCe fhG0ZfhhAvP4nkV+Ui6cxFdWM/vM0Or+OF1KnI8BsCoWkMpyDU7WahUXQ8HhjnUv RkKKkXG3K0jcYeh1yLB4p1miF1tt060Z09558aUHtnFto6vNOtE1VE56aI8TJvzo qAN33CB7jWe++RfqjI0hismVbCjTNxivk48+6qKzdjS4JsgoqGGqxMYqnJzBMbf5 rUAM8yj6zH74WkWELWsv9ZlxCQ9CAEOWEeP4eWLFgQ1arngjeymdAVy04frQB+Dy Q1mfUHb1Sj+c6y7pgbHXtAOaX6CjWg== =EGgz -----END PGP SIGNATURE----- --QM8UBU9P046DRTWO--