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 D8A05C433EF for ; Wed, 19 Jan 2022 19:32:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240141AbiASTcb (ORCPT ); Wed, 19 Jan 2022 14:32:31 -0500 Received: from mga02.intel.com ([134.134.136.20]:51948 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238608AbiASTc0 (ORCPT ); Wed, 19 Jan 2022 14:32:26 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1642620746; x=1674156746; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=hA5pSNQjxDTLN0gQu3qfl7xtlPzKT55FdGnVp2YHmjo=; b=n2RzNA0cu70jI0tKMlC8cgrd1/NaO9fD1K1V1Ju2f9M+X82zYNCTYZFi +n6NZ2aqRDqdlzc4jIJAgZ76AeLnskoi/OwFNUBhoEG0hn8pD82nIWJfz bodapKd9ek8gCBTtk/k+iWIdE3qoRFfJm+2G2J3xu6phTGNbg8gsQt0li 7JPWFWa12RUnmYYt6dXG+N9ZSSsqwVBFc67kgpfTSIOsq5VP41JijYsUV sB5jUoBwF4BExbpJdTyH7lkEVeHTOT0otv7K+ZJrgnaFU+GBsWILq0bl0 BTr0KB3foyg0UzSHG7fESjJTzg7P9EkZXnXdxQRqBx/vmib8rxJ0p7aNz A==; X-IronPort-AV: E=McAfee;i="6200,9189,10231"; a="232534823" X-IronPort-AV: E=Sophos;i="5.88,300,1635231600"; d="scan'208";a="232534823" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Jan 2022 11:18:55 -0800 X-IronPort-AV: E=Sophos;i="5.88,300,1635231600"; d="scan'208";a="530741414" Received: from smile.fi.intel.com ([10.237.72.61]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Jan 2022 11:18:46 -0800 Received: from andy by smile.fi.intel.com with local (Exim 4.95) (envelope-from ) id 1nAGSd-00CETd-Sx; Wed, 19 Jan 2022 21:17:35 +0200 Date: Wed, 19 Jan 2022 21:17:35 +0200 From: Andy Shevchenko To: Esaki Tomohito Cc: dri-devel@lists.freedesktop.org, Alex Deucher , Christian =?iso-8859-1?Q?K=F6nig?= , "Pan, Xinhui" , David Airlie , Daniel Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Ben Skeggs , Michel =?iso-8859-1?Q?D=E4nzer?= , Simon Ser , Qingqing Zhuo , Bas Nieuwenhuizen , Mark Yacoub , Sean Paul , Evan Quan , Petr Mladek , Sakari Ailus , Lee Jones , Abhinav Kumar , Dmitry Baryshkov , Rob Clark , amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, nouveau@lists.freedesktop.org, Daniel Stone , Laurent Pinchart , Damian Hobson-Garcia , Takanari Hayama Subject: Re: [RFC PATCH v3 2/3] drm: add support modifiers for drivers whose planes only support linear layout Message-ID: References: <20220114101753.24996-1-etom@igel.co.jp> <20220114101753.24996-3-etom@igel.co.jp> <0cf405a1-0d2d-ed5e-abdf-be645e7a9209@igel.co.jp> <94bddda6-9823-6479-bc1d-cbb8c1079877@igel.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <94bddda6-9823-6479-bc1d-cbb8c1079877@igel.co.jp> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 19, 2022 at 11:35:22AM +0900, Esaki Tomohito wrote: > On 2022/01/18 18:53, Andy Shevchenko wrote: > > On Mon, Jan 17, 2022 at 02:15:48PM +0900, Esaki Tomohito wrote: > > > On 2022/01/14 23:16, Andy Shevchenko wrote: > > > > On Fri, Jan 14, 2022 at 07:17:52PM +0900, Tomohito Esaki wrote: > > > > > The LINEAR modifier is advertised as default if a driver doesn't specify > > > > > modifiers. > > > > > > > > ... > > > > > > > > > + const uint64_t default_modifiers[] = { > > > > > + DRM_FORMAT_MOD_LINEAR, > > > > > + DRM_FORMAT_MOD_INVALID > > > > > > > > + Comma? > > > > > > There is no mention in the coding style about adding/removing a comma to the > > > last element of an array. Is there a policy in drm driver? > > > > > > I think the advantage of adding a comma to the last element of an array is > > > that diff is only one line when an element is added to the end. > > > However since INVALID is always the last element in the modifiers array, I > > > think it can be either in this case. > > > If there is a policy, I will match it. > > > > Indeed, but there is a common sense. The idea behind (multi-line) definitions > > that when next time somebody will add an element in the array, there are will > > be: > > > > a) no additional churn (like in case of this patch, if the item will be added > > at the bottom; > > > > b) an element that may not be added behind the terminator, which will look > > weird. > > > > That said, the question is if the element is terminator one or not, if not, > > comma is better than no comma and vise versa. > > Ah I see. In this case, DRM_FORMAT_MOD_INVALID is terminator, so it > should not have a comma. Thanks for pointing this out. In this case we are good and any new item, AFAIU, must be added before _INVALID one. -- With Best Regards, Andy Shevchenko