From mboxrd@z Thu Jan 1 00:00:00 1970 From: "David Woodhouse" Subject: Re: [PATCH v4 00/13] Add ACPI _DSD and unified device properties support Date: Wed, 15 Oct 2014 14:08:09 -0000 Message-ID: References: <2660541.BycO7TFnA2@vostro.rjw.lan> <1413378271.2762.77.camel@infradead.org> <20141015131551.GC20034@leverpostej> <1413379736.2762.79.camel@infradead.org> <20141015134209.GD20034@leverpostej> Mime-Version: 1.0 Content-Type: text/plain;charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20141015134209.GD20034@leverpostej> Sender: linux-acpi-owner@vger.kernel.org To: Mark Rutland Cc: David Woodhouse , "Rafael J. Wysocki" , Linux Kernel Mailing List , Greg Kroah-Hartman , Mika Westerberg , ACPI Devel Maling List , Aaron Lu , "devicetree@vger.kernel.org" , Linus Walleij , Alexandre Courbot , Dmitry Torokhov , Bryan Wu , "grant.likely@linaro.org" , Arnd Bergmann , Darren Hart List-Id: devicetree@vger.kernel.org > We have been checking for all DT platforms, and that's a bug for DT. > Copying that bug to ACPI is inexcusable given we know it's a bug to do > so. We'll, perhaps it should be named 'used-by-firmware' and actually it's just as valid under ACPI as it is on RTAS systems. All it does is stop the OS from using the port. > I understand that. However, where a binding doesn't make sense (as in > this case), it shouldn't be enabled for ACPI as it provides a larger > surface area for misuse, for no benefit. These are *optional* properties. They were optional precisely *because* they only make sense in some cases. I don't know that it makes sense to take them away. The benefit we get is *consistency*. For example if someone *does* use the property in question as 'used-by-firmware' and expects the OS not to touch it, we don't want that to change behaviour between ACPI and fdt boots. -- dwmw2