From mboxrd@z Thu Jan 1 00:00:00 1970 From: Karol Kozimor Subject: Re: Centrino question Date: Wed, 26 May 2004 01:56:10 +0200 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: <20040525235610.GA21791@hell.org.pl> References: <3ACA40606221794F80A5670F0AF15F8404622C57@PDSMSX403.ccr.corp.intel.com> <20040520015748.776d5b84.neurowork@free.fr> <1085111429.12352.563.camel@dhcppc4> <20040521125637.33f69fc6.neurowork@free.fr> <20040521115207.GA12775@hell.org.pl> <1085161136.9856.5.camel@Neuromancer.home.net> <1085527691.9167.39.camel@dorker.boxed.no> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-2 Return-path: Content-Disposition: inline In-Reply-To: <1085527691.9167.39.camel-x1HDAq6LUf79HyLP1LL8ZA@public.gmane.org> Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Alexander Hoogerhuis Cc: Ow Mun Heng , acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Thus wrote Alexander Hoogerhuis: > I've been through tracking down what disables C3 on my laptop (HP > nc6000). It all happens when the uhci-hci USB drviver goes in. When I > queried about it on lkml a while back it was due tro some support > lacking in the UHCI dirvers as of yet. Whenever something is plugged into the controller, bus mastering kicks in and C3 is effectively disabled, also on Windows. This is, to my best knowledge, a limitation of the USB interface itself. As far as I know, at least uhci-hcd driver in 2.6 suspends the controller when nothing is plugged in, thus allowing to use C3. The situation might be different under 2.4. Best regards, -- Karol 'sziwan' Kozimor sziwan-DETuoxkZsSqrDJvtcaxF/A@public.gmane.org ------------------------------------------------------- This SF.Net email is sponsored by: Oracle 10g Get certified on the hottest thing ever to hit the market... Oracle 10g. Take an Oracle 10g class now, and we'll give you the exam FREE. http://ads.osdn.com/?ad_id=3149&alloc_id=8166&op=click