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 C4410C7EE2E for ; Mon, 12 Jun 2023 12:48:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233280AbjFLMsX (ORCPT ); Mon, 12 Jun 2023 08:48:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36744 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229639AbjFLMsW (ORCPT ); Mon, 12 Jun 2023 08:48:22 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2E813E51; Mon, 12 Jun 2023 05:48:21 -0700 (PDT) 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 BD267615DA; Mon, 12 Jun 2023 12:48:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8FBFBC433EF; Mon, 12 Jun 2023 12:48:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1686574100; bh=v4Z8rlRMT58I5wgb/bRfwh8250zpxCQEUMup4PFg33E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=N29rIO+VqXsARmgbLd3uP6mrezsJ7tzFZAFOS8qcDXJx0ldhFBigJPWeDZaclw4oj JUsBe0iSPz343rXXioDRPpmM5nQxeNqKjzABOZAfLwMqGspWPnPbMEt9RIy6bIgrnt SwhF5fhSuXRTflRjPywGKMrKIWZXU5jpXDw5sjhX2okApKVmDJ/J/h4lf+xXpOwJOq pLEgf5Bo4PrcsqIwru87FmIAAndIcVaKqZU7F1Sbor7RydUbz8hvwIaBfhH4c8ahVt 2lfroueintxEV6u2vQzw/D6K6kJgCuqgyh7ZyAIAazz3qJsOeuInPlZshdQsSV/X22 oUcYyLoj161aw== Date: Mon, 12 Jun 2023 14:48:17 +0200 From: Wolfram Sang To: Geert Uytterhoeven Cc: Krzysztof Kozlowski , Laurent Pinchart , Geert Uytterhoeven , Rob Herring , Conor Dooley , Andrzej Hajda , Neil Armstrong , Robert Foss , David Airlie , Daniel Vetter , Kieran Bingham , Mauro Carvalho Chehab , Hans Verkuil , Alessandro Zummo , Alexandre Belloni , Jonas Karlman , Jernej Skrabec , Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= , Corey Minyard , Marek =?utf-8?B?QmVow7pu?= , Jiasheng Jiang , Antonio Borneo , Abhinav Kumar , Ahmad Fatoum , "dri-devel@lists.freedesktop.org" , "linux-i2c@vger.kernel.org" , "linux-media@vger.kernel.org" , Fabrizio Castro , "linux-renesas-soc@vger.kernel.org" , Mark Brown Subject: Re: [PATCH v5 01/11] i2c: Enhance i2c_new_ancillary_device API Message-ID: Mail-Followup-To: Wolfram Sang , Geert Uytterhoeven , Krzysztof Kozlowski , Laurent Pinchart , Geert Uytterhoeven , Rob Herring , Conor Dooley , Andrzej Hajda , Neil Armstrong , Robert Foss , David Airlie , Daniel Vetter , Kieran Bingham , Mauro Carvalho Chehab , Hans Verkuil , Alessandro Zummo , Alexandre Belloni , Jonas Karlman , Jernej Skrabec , Uwe =?utf-8?Q?Kleine-K=C3=B6nig?= , Corey Minyard , Marek =?utf-8?B?QmVow7pu?= , Jiasheng Jiang , Antonio Borneo , Abhinav Kumar , Ahmad Fatoum , "dri-devel@lists.freedesktop.org" , "linux-i2c@vger.kernel.org" , "linux-media@vger.kernel.org" , Fabrizio Castro , "linux-renesas-soc@vger.kernel.org" , Mark Brown References: <20230608103929.GO5058@pendragon.ideasonboard.com> <20230608125019.GD26742@pendragon.ideasonboard.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="WvJDwm/Hwewvo4Eu" Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org --WvJDwm/Hwewvo4Eu Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Geert, > > Would this binding allow to not use the RTC if the second reg is > > missing? What are the advantages of not enabling RTC? Saving power? >=20 > It doesn't work if there is no clock? Maybe I am confusing something now, but if the RTC _needs_ to be enabled, then why we don't do it unconditionally? > > Thinking more about this: DT is hardware description, so the RTC should > > always be described in DT. If the RTC is actually activated is more a > > configuration thing, or? Brainstorming: maybe the PMIC driver could try > > to find the node with reg =3D=3D 0x6f and see if firmware has enabled i= t or > > not? >=20 > I guess the RTC part would acknowledge anyway? > It is always present, it is just part of the RAA215300. I mean the driver should scan for the DT node. Not on the bus. But a phandle is probably safer. > Sure, you can put that in DT. But it's a pity you have to do that, > as the device (the PMIC part) does know the revision... > That's why I suggested to let the PMIC part instantiate an i2c ancillary > device... I see. I'll let it sink in some more. Happy hacking, Wolfram --WvJDwm/Hwewvo4Eu Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmSHFAwACgkQFA3kzBSg KbZwkw/9Gsje3G0GrpSg0bBAo/lCUg0W8jr/9SckwE+ZV+oyUifFj3f6UGBYOUh3 3lp01hw8HMpNx7UGEXeqtks0XJx/NvrQSrEo9evQFxbqD1bknR3/rVSazPYq2YVU OIKnMgtDFwbNFTW4Z1XrWkTid0GiwMxjwPYOGpggHz/dCC0X7sbSYVjB5Mp8AtQq QMbtztNNvpRK3myi3gXoydxt45elOyxYqNUzqA8LE0VSrngKkbJ9bfsjzFVzMmYs JZyhMjKyKv37qTsLrOEDOK0+Af9ObWx+1eEmb6zuJiaxzVZiEI4EQC211aUgYW+i WuaTobtQLvXPGdYqCZFj+a5TjIZM5a1zUos1yleeJPhA64x7ZL9KlwkwpMSEW8bq 5XvVFrbFtOLQmYMBY5u1DdPyLC/4oi7uMdX0MHm92Y1+7syj46fnxEiwjqTeVOu/ 7DL1ubJ84p0uAyQXbBBeXMFh5FlTvPL/4a61irbaoHw9d7U2DUs83Xj3zEYXsXmG Ni02dcZRUMuUKti8CYEhWtlCXbbkKOtvspFdTPGN0F9Q0v6+XW6WScBuivMTVy2E zhp4luTeRE7bguizBbUSdjRYAVUa/ibYqRzfKaLsYmU7W34RHa5DI+aK4BqOU+sB kEUSvcw5kVL33AwvwSzcvPF/qFMI+cYvxAORB6rvoMdOU+CkTYA= =KA5H -----END PGP SIGNATURE----- --WvJDwm/Hwewvo4Eu--