Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264073AbTEOPPQ (ORCPT ); Thu, 15 May 2003 11:15:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264077AbTEOPPQ (ORCPT ); Thu, 15 May 2003 11:15:16 -0400 Received: from h-68-165-86-241.DLLATX37.covad.net ([68.165.86.241]:41782 "EHLO sol.microgate.com") by vger.kernel.org with ESMTP id S264073AbTEOPPO (ORCPT ); Thu, 15 May 2003 11:15:14 -0400 Subject: Re: Test Patch: 2.5.69 Interrupt Latency From: Paul Fulghum To: Alan Stern Cc: Greg KH , Andrew Morton , "linux-kernel@vger.kernel.org" , Arnd Bergmann , johannes@erdfelt.com, USB development list In-Reply-To: References: Content-Type: text/plain Organization: Message-Id: <1053012368.2026.6.camel@diemos> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.2 (1.2.2-4) Date: 15 May 2003 10:26:08 -0500 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1117 Lines: 35 I think I found the key to this whole problem: Note:I mistakenly referred to the chipset as PIIX3 in previous messages, in fact it is the PIIX4 (BX) The PIIX4 errata states that false resume indications can be generated if CLK48 is active during an overcondition indication (OC[1..0]). Sure enough, the USBPORTSC[12] registers constantly report a status of 0C80 which shows that both ports are showing overcurrent condition (which disables the associated port). My guess is that HP deliberately tied the OC[1..0] inputs active to force the ports to a disabled state. So checking for the case of both ports constantly in OC condition and disabled may be a reasonable way to either disable the controller altogether or at least not do the wakeup/suspend shuffle. Any comments? -- Paul Fulghum, paulkf@microgate.com Microgate Corporation, http://www.microgate.com - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/