From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752470AbeDDTUJ (ORCPT ); Wed, 4 Apr 2018 15:20:09 -0400 Received: from smtp62.i.mail.ru ([217.69.128.42]:52150 "EHLO smtp62.i.mail.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752424AbeDDTUH (ORCPT ); Wed, 4 Apr 2018 15:20:07 -0400 Subject: Re: [PATCH v2 1/6] spi: core: handle timeout error from transfer_one() To: Maxime Ripard Cc: Chen-Yu Tsai , Mark Brown , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-spi@vger.kernel.org References: <20180403152905.1524-1-ssuloev@orpaltech.com> <20180403152905.1524-2-ssuloev@orpaltech.com> <20180403155224.GA11578@sirena.org.uk> <20180403161824.GB11578@sirena.org.uk> <20180404070817.6cens44jvlmdaxtm@flea> From: Sergey Suloev Message-ID: Date: Wed, 4 Apr 2018 22:19:59 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <20180404070817.6cens44jvlmdaxtm@flea> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Authentication-Results: smtp62.i.mail.ru; auth=pass smtp.auth=ssuloev@orpaltech.com smtp.mailfrom=ssuloev@orpaltech.com X-7FA49CB5: 0D63561A33F958A56F5296078A3C987776889ED789FDEA0FFC839A7D10C5E1E9725E5C173C3A84C3A1C30C8AFC676C8B9AD636F337C3FD3E5E1C53F199C2BB95B5C8C57E37DE458B4C7702A67D5C3316FA3894348FB808DB48C21F01D89DB561574AF45C6390F7469DAA53EE0834AAEE X-Mailru-Sender: C5364AD02485212F3ACDC11E67D84917B83A51F760C4735767E24D0D576F94E6069BFC61DABEEB110841D3AAAB1726C63DDE9B364B0DF289264D2CD8C2503E8C22A194DADEED8EEDCA01A23BA9CD1BE7ED14614B50AE0675 X-Mras: OK Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/04/2018 10:08 AM, Maxime Ripard wrote: > On Tue, Apr 03, 2018 at 07:24:11PM +0300, Sergey Suloev wrote: >> On 04/03/2018 07:18 PM, Mark Brown wrote: >>> On Tue, Apr 03, 2018 at 07:00:55PM +0300, Sergey Suloev wrote: >>>> On 04/03/2018 06:52 PM, Mark Brown wrote: >>>>> On Tue, Apr 03, 2018 at 06:29:00PM +0300, Sergey Suloev wrote: >>>>>> As long as sun4i/sun6i SPI drivers have overriden the default >>>>>> "wait for completion" procedure then we need to properly >>>>>> handle -ETIMEDOUT error from transfer_one(). >>>>> Why is this connected to those drivers specifically? >>>> These 2 drivers have their own "waiting" code and not using the code from >>>> SPI core. >>> Does this not apply to any other driver - why is this something we only >>> have to do when these drivers do it? That's what's setting off alarm >>> bells. >> sun4i/sun6i drivers have let's say "smart" waiting while SPI core uses a >> fixed interval to wait. >> >> I can't say for every SPI driver in kernel, that's outside of my area of >> expertise. > I'm not sure what's specific about the sun4i / sun6i case here. Your > patch doesn't have anything to do with the delay before the timeout, > but the fact that we return -ETIMEDOUT in the first place. > > And I'm pretty sure that papering over an error returned by a driver > is not the right thing to do. > > Maxime > > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel do you mean the changes in spi.c are not required at all ? My point was to eat ETIMEDOUT error from transfer_one() as it is just a mark and shouldn't be handled as a normal error.