Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031211AbWI0XFH (ORCPT ); Wed, 27 Sep 2006 19:05:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1031212AbWI0XFG (ORCPT ); Wed, 27 Sep 2006 19:05:06 -0400 Received: from smtp101.sbc.mail.mud.yahoo.com ([68.142.198.200]:45961 "HELO smtp101.sbc.mail.mud.yahoo.com") by vger.kernel.org with SMTP id S1031211AbWI0XFB (ORCPT ); Wed, 27 Sep 2006 19:05:01 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=pacbell.net; h=Received:From:To:Subject:Date:User-Agent:Cc:References:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-Disposition:Message-Id; b=Lswdf9D57hlscOyUef9eHzlgq68OdWoKudko4Y8lmft6+8PDV5L81c/A/Tmc/aEJYDJDTzdk3qPF+jKmofpH4Xx0AyOSd2yVlit6+6gHHsWnINFjOyIy3iWMO11DtyoQj+qhuJjTwJR9cDYNkrAn5k17K9zuRbunLzp2kLRb0DY= ; From: David Brownell To: linux-usb-devel@lists.sourceforge.net Subject: Re: [linux-usb-devel] usb still sucks battery in -rc7-mm1 Date: Wed, 27 Sep 2006 15:46:16 -0700 User-Agent: KMail/1.7.1 Cc: "Theodoros V. Kalamatianos" , Pavel Machek , Greg KH , kernel list References: <20060924090858.GA1852@elf.ucw.cz> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200609271546.16604.david-b@pacbell.net> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1168 Lines: 23 On Sunday 24 September 2006 5:18 am, Theodoros V. Kalamatianos wrote: > I have encountered at least 3 hubs (2 usb2 & 1 usb1) that will consume a > lot of power (about 2-2.5W if the laptop power consumption readings are to > be trusted) and heat up a lot (to the point of being too hot to touch for > more than a few seconds) even when no devices are connected, at least on > Linux. I have not tested them on a Windows machine to see if this is the > case there. The USB2 ones used Cypress chips. I do not know what your h/w > config is, but perhaps this is a similar case ? Probably not unrelated. I have one of those Cypress-based hubs; it's nice except for the heat/power, which precludes using them in bus-powered mode with a laptop (or anything) ... I don't much like wall-warts! It might be too much to expect that when that hub's upstream port is suspended, its power usage goes to something reasonable. - 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/