From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans de Goede Subject: Re: [PATCH v4 4/4] ARM: mvebu: Armada 385 GP: Add regulators to the SATA port Date: Sun, 18 Jan 2015 16:29:02 +0100 Message-ID: <54BBD13E.6030901@redhat.com> References: <1421330978-9694-5-git-send-email-gregory.clement@free-electrons.com> <54B8C933.7020502@redhat.com> <54B8D97B.3090908@free-electrons.com> <54B8E38A.6020709@redhat.com> <20150116123705.GM3043@sirena.org.uk> <54B9629C.9090800@redhat.com> <20150116202516.GL3856@sirena.org.uk> <54BA21F9.5050408@redhat.com> <20150117131404.GA6414@sirena.org.uk> <54BA7197.40301@redhat.com> <20150118123531.GA2809@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20150118123531.GA2809@sirena.org.uk> Sender: linux-ide-owner@vger.kernel.org To: Mark Brown Cc: Gregory CLEMENT , Tejun Heo , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, =?windows-1252?Q?Antoine_T=E9nart?= , Liam Girdwood , Thomas Petazzoni , Ezequiel Garcia , Maxime Ripard , Boris BREZILLON , Jason Cooper , Andrew Lunn , Sebastian Hesselbarth , linux-arm-kernel@lists.infradead.org, Lior Amsalem , Tawfik Bayouk , Nadav Haklai , Mark Rutland , devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org Hi, On 18-01-15 13:35, Mark Brown wrote: > On Sat, Jan 17, 2015 at 03:28:39PM +0100, Hans de Goede wrote: >> On 17-01-15 14:14, Mark Brown wrote: > >>> Following your argument to the logical conclusion means we can never >>> turn any regualtor off - we always have the risk that there's another >>> shared user which is going to get a power bounce if we power down. More >>> directly we'll also get people complaining that we're burning power >>> pointlessly on their systems for devices they've not even got drivers >>> enabled for. This powering down is something there's been user demand >>> for. > >> Right, note I'm only advocating to not turn off regulators marked as >> regulator-boot-on. I would expect any regulator to have such a >> marking to have at least one user with an actual driver. If people decide >> to not build that driver, and then complain we can simply tell them to >> build the driver ... > > Right, but that's not what regulator-boot-on actually means (and I'm not > sure why you would think it would TBH) Well, the meaning of regulator-boot-on is not clearly defined really, to begin we need with fixing that, currently all the bindings file says is: - regulator-boot-on: bootloader/firmware enabled regulator One could easily argue that the bootloader likely has a good reason to turn the regulator on, and that unless there is a specific driver which claims the regulator and thus knows what to do with it it is best left alone ... > so this will disrupt existing > users who are expecting the current behaviour. We could try adding a > new property but it doesn't feel very idiomatic for DT which isn't very > nice. > > Telling people not to build the driver doesn't in general work any > better than telling them to build it in I fear, it seems like it's > essentially just shuffling things around so people have to change their > kernel config in a different way to avoid issues. Regards, Hans