From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: Re: [PATCH] backlight: add support for disabling backlights via sysfs Date: Fri, 29 Jun 2012 03:57:24 +0100 Message-ID: <20120629025724.GB18605@srcf.ucam.org> References: <1340910426-13269-1-git-send-email-seth.forshee@canonical.com> <20120628191043.GA9777@srcf.ucam.org> <20120628193017.GA29456@thinkpad-t410> <20120628193652.GB10945@srcf.ucam.org> <20120628211600.GB29456@thinkpad-t410> <20120628211936.GA14286@srcf.ucam.org> <1340937839.6196.212.camel@linux-s257.site> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1340937839.6196.212.camel@linux-s257.site> Sender: linux-kernel-owner@vger.kernel.org To: joeyli Cc: seth.forshee@canonical.com, Richard Purdie , linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org, Corentin Chary List-Id: platform-driver-x86.vger.kernel.org On Fri, Jun 29, 2012 at 10:43:59AM +0800, joeyli wrote: > http://msdn.microsoft.com/en-us/windows/hardware/gg487382.aspx > > In WDDM architecture, in spec p.5, there have a "Monitor" driver to > check the WDDM driver support brightness DDI, if not, then it will use > standard acpi method to control brightness. What's the interaction between GPU drivers and platform drivers? For instance, on acer systems that have backlight control via WMI, does Windows use WMI, the GPU driver or ACPI? -- Matthew Garrett | mjg59@srcf.ucam.org