From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: ACPI S3 suspend and LCD backlight Date: Wed, 16 Nov 2005 22:02:49 +0100 Message-ID: <20051116210249.GA12561@elf.ucw.cz> References: <200511130639.jAD6d42Y011608@dragonslair.panasol.com> <20051114131728.GA22957@srcf.ucam.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20051114131728.GA22957-1xO5oi07KQx4cg9Nei1l7Q@public.gmane.org> Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Matthew Garrett Cc: yauh-acpi-CDzBh2wLF5MAvxtiuMwx3w@public.gmane.org, acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Hi! > > It appears something in the ACPI suspend code turns on the > > LCD backlight to print out the diagnostic messages. Is there any > > way to prevent this? Alternatively, is there a place in the drive > > I can add a sequence to turn off the display just before it goes > > to sleep? > > No, the ACPI suspend code doesn't do this (as far as I can tell). If you > suspend from X, the kernel will switch away from X and X will restore > the console state - which probably includes switching the backlight back > on. ACPI does switch consoles, which may cause something like that... see kernel/power/console.c . Pavel -- Thanks, Sharp! ------------------------------------------------------- This SF.Net email is sponsored by the JBoss Inc. Get Certified Today Register for a JBoss Training Course. Free Certification Exam for All Training Attendees Through End of 2005. For more info visit: http://ads.osdn.com/?ad_id=7628&alloc_id=16845&op=click