From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Szyprowski Subject: Re: [PATCH v3] regulator: treat regulators with constant volatage as fixed Date: Tue, 20 Nov 2012 14:20:20 +0100 Message-ID: <50AB8394.1010207@samsung.com> References: <20121113094255.GW18224@opensource.wolfsonmicro.com> <1352800177-16139-1-git-send-email-m.szyprowski@samsung.com> <20121114020124.GH4415@opensource.wolfsonmicro.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <20121114020124.GH4415@opensource.wolfsonmicro.com> Sender: linux-kernel-owner@vger.kernel.org To: Mark Brown Cc: linux-kernel@vger.kernel.org, linux-mmc@vger.kernel.org, Kyungmin Park , Liam Girdwood , Chris Ball List-Id: linux-mmc@vger.kernel.org Hello, On 11/14/2012 3:01 AM, Mark Brown wrote: > On Tue, Nov 13, 2012 at 10:49:37AM +0100, Marek Szyprowski wrote: > > > + if (rdev->constraints->valid_ops_mask & REGULATOR_CHANGE_VOLTAGE) { > > + if (rdev->desc->n_voltages) > > + return rdev->desc->n_voltages; > > + else > > + return -EINVAL; > > + } else { > > + return 1; > > + } > > Hrm, now I can read the logic I'm not convinced this is a good idea. > This will report that we have an available voltage for devices which > don't know their voltage (things like battery supplies often do this as > the voltage is unregulated) and it will mean that we are doing something > different for the case where there's only one voltage (reporting the > restricted count instead of the physically supported count). > > I think we want a regulator_can_change_voltage() or possibly a count > function (though I can't see any use cases except this) which answers > the question directly instead of layering on top of this function. Right, regulator_can_change_voltage() sounds much better than my hacky approach. The first client would be probably sdhci/mmc driver, as 'can_change_voltage' check sounds much more appropriate than counting available voltage values. I will prepare patches soon. Best regards -- Marek Szyprowski Samsung Poland R&D Center