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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 5986AC10F11 for ; Wed, 10 Apr 2019 12:01:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2EE9620818 for ; Wed, 10 Apr 2019 12:01:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731639AbfDJMBU convert rfc822-to-8bit (ORCPT ); Wed, 10 Apr 2019 08:01:20 -0400 Received: from smtp.asem.it ([151.1.184.197]:56986 "EHLO smtp.asem.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727515AbfDJMBU (ORCPT ); Wed, 10 Apr 2019 08:01:20 -0400 Received: from webmail.asem.it by asem.it (smtp.asem.it) (SecurityGateway 5.5.0) with ESMTP id SG003804311.MSG for ; Wed, 10 Apr 2019 14:01:16 +0200S Received: from ASAS044.asem.intra (172.16.16.44) by ASAS044.asem.intra (172.16.16.44) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1261.35; Wed, 10 Apr 2019 14:01:15 +0200 Received: from ASAS044.asem.intra ([::1]) by ASAS044.asem.intra ([::1]) with mapi id 15.01.1261.035; Wed, 10 Apr 2019 14:01:15 +0200 From: Flavio Suligoi To: Mark Brown CC: Daniel Mack , Haojian Zhuang , Robert Jarzmik , "linux-arm-kernel@lists.infradead.org" , "linux-spi@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: RE: [PATCH 1/1] spi: pxa2xx: add driver enabling message Thread-Topic: [PATCH 1/1] spi: pxa2xx: add driver enabling message Thread-Index: AQHU7h76xswpdz/DmEySUaMIIqbaa6Y1E7kAgAAzYSD//+NxgIAAIlmw Date: Wed, 10 Apr 2019 12:01:15 +0000 Message-ID: <6953cafeb6bc4367842f37f567bb893f@asem.it> References: <1554736964-6058-1-git-send-email-f.suligoi@asem.it> <20190410103250.GF6106@sirena.org.uk> <20190410115431.GO6106@sirena.org.uk> In-Reply-To: <20190410115431.GO6106@sirena.org.uk> Accept-Language: it-IT, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [172.16.17.208] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 X-SGHeloLookup-Result: pass smtp.helo=webmail.asem.it (ip=172.16.16.44) X-SGSPF-Result: none (smtp.asem.it) X-SGOP-RefID: str=0001.0A0B020B.5CADDB0B.0086,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0 (_st=1 _vt=0 _iwf=0) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Wed, Apr 10, 2019 at 11:47:43AM +0000, Flavio Suligoi wrote: > > > You have right about to avoid too many boot messages, > > but in this case, using an x86 machine and with > > the spi-pxa2xx in DMA mode, so without the message: > > > "no DMA channels available, using PIO", > > > there is absolutely no indication about the existence > > of the SPI master controller. > > It's totally fine to not have a boot print for the device, the best way > to find devices if you need them is to look in sysfs anyway. Ok > > The second reason is about the DMA/PIO mode indication. > > With the board I'm using, sometimes the spi-pxa2xx driver can't allocate > > a DMA channel and works in PIO mode. > > > So, with the advice of Jarkko, I think that a valid solution could be: > > > 1) remove the "no DMA channels available, using PIO" message > > 2) add a new message with the indications of: > > - controller mode (slave or master) > > - transfer mode (DMA or PIO) > > > What do you think about this? > > If the system is randomly failing to assign a DMA channel when it should > then shouldn't we just fix that? A print which is presumably intended > to prompt the user to reboot to try to get things working doesn't seem > like a good solution. Right, I'm just fix the DMA problem (I'm preparing a patch about this) Flavio