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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 AB59FC4338F for ; Wed, 25 Aug 2021 13:59:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 818E7610E5 for ; Wed, 25 Aug 2021 13:59:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239601AbhHYOAg (ORCPT ); Wed, 25 Aug 2021 10:00:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34266 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232058AbhHYOAg (ORCPT ); Wed, 25 Aug 2021 10:00:36 -0400 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 558AEC061757; Wed, 25 Aug 2021 06:59:50 -0700 (PDT) Received: from pendragon.ideasonboard.com (62-78-145-57.bb.dnainternet.fi [62.78.145.57]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 6440C24F; Wed, 25 Aug 2021 15:59:47 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1629899987; bh=lAmUs2tEJMT77bx/hltss4KbUysanylpuQF7pGqzjI8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=W/KpBlPGtnBk7vh4xNcqJn+SPcuecSu9D8RHULsAnQOfc7Byhh2czJeuH1ioEeBSi XvGveC5Arnp8bgsmcMIQyHs3xmjKNF9NH/YvI6SPSJ3aviDmCkh7mSer25sEjE0Old 9lejdGCJD4QLhkuKtKwqRql2hDb3sRICevYNpW0M= Date: Wed, 25 Aug 2021 16:59:35 +0300 From: Laurent Pinchart To: Mark Brown Cc: Andy Shevchenko , Daniel Scally , Linux Kernel Mailing List , Platform Driver , Liam Girdwood , Hans de Goede , Mark Gross , Maximilian Luz , Kieran Bingham , sailues@pendragon.ideasonboard.com Subject: Re: [RFC PATCH v2 1/3] regulator: core: Add regulator_lookup_list Message-ID: References: <20210824230620.1003828-1-djrscally@gmail.com> <20210824230620.1003828-2-djrscally@gmail.com> <20210825103301.GC5186@sirena.org.uk> <20210825113013.GD5186@sirena.org.uk> <20210825131139.GG5186@sirena.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20210825131139.GG5186@sirena.org.uk> Precedence: bulk List-ID: X-Mailing-List: platform-driver-x86@vger.kernel.org Hello, CC'ing Sakari. On Wed, Aug 25, 2021 at 02:11:39PM +0100, Mark Brown wrote: > On Wed, Aug 25, 2021 at 03:26:37PM +0300, Andy Shevchenko wrote: > > On Wed, Aug 25, 2021 at 2:30 PM Mark Brown wrote: > > > > No, what was proposed for regulator was to duplicate all the the DT > > > binding code in the regulator framework so it parses fwnodes then have > > > an API for encoding fwnodes from C data structures at runtime. The bit > > > where the data gets joined up with the devices isn't the problem, it's > > > the duplication and fragility introduced by encoding everything into > > > an intermediate representation that has no purpose and passing that > > > around which is the problem. > > > The whole exercise with swnode is to minimize the driver intrusion and > > evolving a unified way for (some) of the device properties. V4L2 won't > > The practical implementation for regulators was to duplicate a > substantial amount of code in the core in order to give us a less type > safe and more indirect way of passing data from onen C file in the > kernel to another. This proposal is a lot better in that it uses the > existing init_data and avoids the huge amounts of duplication, it's just > not clear from the changelog why it's doing this in a regulator specific > manner. > > *Please* stop trying to force swnodes in everywhere, take on board the > feedback about why the swnode implementation is completely inappropriate > for regulators. I don't understand why you continue to push this so > hard. swnodes and fwnodes are a solution to a specific problem, they're > not the answer to every problem out there and having to rehash this > continually is getting in the way of actually discussing practical > workarounds for these poorly implemented ACPI platforms. > > > like what you are suggesting exactly because they don't like the idea > > of spreading the board code over the drivers. In some cases it might > > even be not so straightforward and easy. > > > Laurent, do I understand correctly the v4l2 expectations? > > There will be some cases where swnodes make sense, for example where the > data is going to be read through the fwnode API since the binding is > firmware neutral which I think is the v4l case. On the other hand > having a direct C representation is a very common way of implementing > DMI quirk tables, and we have things like the regulator API where > there's off the shelf platform data support and we actively don't want > to support fwnode. >From a camera sensor point of view, we want to avoid code duplication. Having to look for regulators using OF lookups *and* platform data in every single sensor driver is not a good solution. This means that, from a camera sensor driver point of view, we want to call regulator_get() (or the devm_ version) with a name, without caring about who establishes the mapping and how the lookup is performed. I don't care much personally if this would be implemented through swnode or a different mechanism, as long as the implementation can be centralized. -- Regards, Laurent Pinchart