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=-5.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 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 8844BC43461 for ; Fri, 4 Sep 2020 14:35:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5A550206D4 for ; Fri, 4 Sep 2020 14:35:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=tq-group.com header.i=@tq-group.com header.b="LkEW6cNW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730513AbgIDOfL (ORCPT ); Fri, 4 Sep 2020 10:35:11 -0400 Received: from mx1.tq-group.com ([62.157.118.193]:32814 "EHLO mx1.tq-group.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727049AbgIDOev (ORCPT ); Fri, 4 Sep 2020 10:34:51 -0400 IronPort-SDR: MRED0OCmkjLNXo8Kz0rHdFOUZXQAYc9NHl180JrekTcYuQIAO0vPEsXeL+umr+g/QzVPwBhdNR AvWaWeCdqCPGTYSKlqEeT3TN0J6ti8UmioQeIMFtFZIYdHtKh1UsAJm/Rzq79pijLpGE6jvnhj u6i0bm57/HjEYqmL9kug62dq9dpP0V+pOwd7HCpaVs8QxzFFbP4awbH0PWoU6KUuLnqkSi8vfk 3gwt9F19U19ZWC35alSqQrEaPYSYrfZgWcEyo8Urfi03icVRs4KjoWtSEdcQvPyYWg9j3GzndC tRQ= X-IronPort-AV: E=Sophos;i="5.76,389,1592863200"; d="scan'208";a="13737379" Received: from unknown (HELO tq-pgp-pr1.tq-net.de) ([192.168.6.15]) by mx1-pgp.tq-group.com with ESMTP; 04 Sep 2020 16:34:43 +0200 Received: from mx1.tq-group.com ([192.168.6.7]) by tq-pgp-pr1.tq-net.de (PGP Universal service); Fri, 04 Sep 2020 16:34:43 +0200 X-PGP-Universal: processed; by tq-pgp-pr1.tq-net.de on Fri, 04 Sep 2020 16:34:43 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1599230083; x=1630766083; h=message-id:subject:from:to:cc:date:in-reply-to: references:mime-version:content-transfer-encoding; bh=T7XiVlDr00IMxMBe764lGNk5PWpuISV6o8DZWMwHMFg=; b=LkEW6cNWfD2yMDFHAcyzgn8dVUHnbsuMNQ93VYO2eFrGIavOcnEJ8XX7 ck4AGrnqy10Y8t+ZwqL2XbOvRHgYB+IlKSI5XPSe0Oz9w3LjV5uIYMzUH prqIxqtcoQjLIo7noYIVp/yY02QHUaitpTfmW2ujDos3Px4Jsvxlo7gtS /aHkXkMr1a0WrK2tPsGeY5WQaYLViDDAcyD3NkXqqyVnwpJ9TN2CTQHSA ECeS/U4ep5JeepQdjp/p1ifeQf97EH7MxKeQNaS3UL3gTNTSMbitUMtaK Qv5VKPVpR0yxvwozdZL+Pc9tTpmuA/v7lLX/CRoRb2wD4CQluO5r9PeAm Q==; IronPort-SDR: XWepbQyV2JQ+1ituWt8O4o77v0i8ltrFzVdO3CzJgRlRnMO1bNPMKAW/gXDaGQtRwqfihgutVX UoAMCc/OKxXSJ6NmGgesXMCjAjFNbnDJqT2kzVktpcuddkgFs13C71LDKHh7YJsO3U2PJiRmCl xUdRn3BMWQMq7OKTd5NskyELgH0o4NyMWVl6PcidcmvLop19HQXhXsr68n9Q3WO6NENrNxmLaz ExALDZnJ2W6IqYfSY09zWjnIwzY1JFn4yd4RyWtEWUOgg8nXfhhQuq0qu4aAAucqIZnEdUoh8t SSM= X-IronPort-AV: E=Sophos;i="5.76,389,1592863200"; d="scan'208";a="13737378" Received: from vtuxmail01.tq-net.de ([10.115.0.20]) by mx1.tq-group.com with ESMTP; 04 Sep 2020 16:34:43 +0200 Received: from schifferm-ubuntu4.tq-net.de (schifferm-ubuntu4.tq-net.de [10.117.49.26]) by vtuxmail01.tq-net.de (Postfix) with ESMTPA id 38FF9280065; Fri, 4 Sep 2020 16:34:43 +0200 (CEST) Message-ID: Subject: Re: (EXT) Re: (EXT) Re: [PATCH] spi-imx: remove num-cs support, set num_chipselect to 4 From: Matthias Schiffer To: Fabio Estevam Cc: Mark Brown , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , NXP Linux Team , linux-spi , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" , linux-kernel Date: Fri, 04 Sep 2020 16:34:43 +0200 In-Reply-To: References: <20200903144028.20416-1-matthias.schiffer@ew.tq-group.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.5-0ubuntu0.18.04.2 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2020-09-04 at 10:57 -0300, Fabio Estevam wrote: > On Fri, Sep 4, 2020 at 10:02 AM Matthias Schiffer > wrote: > > > This would make num_chipselect default to 1 again (set by > > __spi_alloc_controller()), breaking every i.MX board that uses more > > than 1 native CS. > > Which boards are that? Are you referring to non-DT i.MX boards? > > If so, I have sent a patch removing all non-DT i.MX boards. > > > I'm aware that using cs-gpios instead of native CS is probably a > > good > > idea in any case, as the native CS of this SPI controller is kinda > > flaky (and at a glance it looks like all in-tree DTs do this; not > > sure > > about board files that don't use DTs?), but I'm not convinced that > > breaking native CS support completely is desirable either. > > Initial i.MX chips with this SPI IP had issues in using chip-select > in > native mode and GPIO chip-select has been used since them. > > Do we have i.MX dts that make use of native chip select? As mentioned in my previous mail, all in-tree DTS use cs-gpios (unless I've overlooked something - I grepped for CSPIn_SSm pinmuxings), so removing support for native CS should not break anything we know of. Nevertheless, I don't see why we should deliberately remove the native CS support - my understanding was that we try to avoid breaking changes to DT interpretation even for unknown/out-of-tree DTS.