From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luis Oliveira Subject: Re: [PATCH] i2c: core: helper function to detect slave mode Date: Mon, 16 Jan 2017 10:32:36 +0000 Message-ID: <7fdf5d3c-d0ea-ec45-6b18-4573fff6dd11@synopsys.com> References: <73246c4a-504c-52d7-dde4-970a45dca0bd@mleia.com> <3748130b-5321-12eb-ec75-e2637dd9fc54@mleia.com> <1484240482.2133.92.camel@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: Received: from smtprelay.synopsys.com ([198.182.47.9]:51547 "EHLO smtprelay.synopsys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751339AbdAPKr4 (ORCPT ); Mon, 16 Jan 2017 05:47:56 -0500 In-Reply-To: <1484240482.2133.92.camel@linux.intel.com> Sender: linux-i2c-owner@vger.kernel.org List-Id: linux-i2c@vger.kernel.org To: Andy Shevchenko , Vladimir Zapolskiy , Andy Shevchenko Cc: Luis Oliveira , Wolfram Sang , Rob Herring , Mark Rutland , Jarkko Nikula , Mika Westerberg , linux-i2c@vger.kernel.org, devicetree , "linux-kernel@vger.kernel.org" , Ramiro.Oliveira@synopsys.com, Joao Pinto , CARLOS.PALMINHA@synopsys.com On 12-Jan-17 17:01, Andy Shevchenko wrote: > On Sat, 2017-01-07 at 03:24 +0200, Vladimir Zapolskiy wrote: >> On 01/07/2017 02:19 AM, Andy Shevchenko wrote: >>> On Sat, Jan 7, 2017 at 1:43 AM, Vladimir Zapolskiy >>> wrote: >>>> On 01/07/2017 12:45 AM, Andy Shevchenko wrote: > >>>>> + } >>>>>>> + } else if (IS_BUILTIN(CONFIG_ACPI) && >>>>>>> ACPI_HANDLE(dev)) { >>>>>>> + dev_dbg(dev, "ACPI slave is not supported >>>>>>> yet\n"); >>>>>>> + } >>>>>> >>>>>> If so, then it might be better to drop else-if stub for now. >>>>> >>>>> Please, don't. >>>>> >>>> >>>> Why do you ask for this stub to be added? >>> >>> 1. Exactly the reason you asked above. Here is the code which has >>> built differently on different platforms. x86 usually is not using >>> CONFIG_OF, ARM doesn't ACPI (versus ARM64). Check GPIO library for >>> existing examples. >> >> From the context by the stub I mean dev_dbg() in >> i2c_slave_mode_detect() >> function, I don't see a connection to GPIO library, please clarify. > > I agree that is not good proof for using IS_ENABLED/IS_BUILTIN macro. I can prepare a V3 and remove it if that's the decision. > >>> 2. We might add that support later, but here is again, just no-op. >>> >>> So, what is your strong argument here against that? >> >> When the support is ready for ACPI case, you'll remove the added >> dev_dbg(), and I don't see a good point by adding it temporarily. > > It would remind me to look at it at some point. > >> What is wrong with the approach of adding the ACPI case handling >> branch when it is ready and remove any kind of stubs right now? > > I will not object. Here is maintainer, let him speak. > >> On ACPI platforms the function returns 'false' always, will the >> function work correctly (= corresponding to its description) as is? > > Yes. >