From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751665AbXAAVwE (ORCPT ); Mon, 1 Jan 2007 16:52:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754357AbXAAVwE (ORCPT ); Mon, 1 Jan 2007 16:52:04 -0500 Received: from smtp-out001.kontent.com ([81.88.40.215]:60985 "EHLO smtp-out.kontent.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751665AbXAAVwD (ORCPT ); Mon, 1 Jan 2007 16:52:03 -0500 From: Oliver Neukum To: Andrew Barr Subject: Re: Cut power to a USB port? Date: Mon, 1 Jan 2007 22:52:02 +0100 User-Agent: KMail/1.8 Cc: linux-kernel@vger.kernel.org References: <1167684985.28023.4.camel@localhost> In-Reply-To: <1167684985.28023.4.camel@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200701012252.02647.oliver@neukum.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Am Montag, 1. Januar 2007 21:56 schrieb Andrew Barr: > I have a simple question perhaps someone can help me with here... > > I have one of those simple LED keyboard lamps that get their power from > the USB port. Is there some way in Linux, using files under /sys I would > imagine, to cut power to the USB port into which this lamp is plugged? I You could use usbfs to send commands to the hub. > know I would have to manually figure out what port it's plugged into, as > it is not a "real" USB device...e.g. it just draws power. I would like > to be able to programmatically switch the lamp on and off. The ability to cut each port's power individually is optional. Your hardware may well be incapable of what you want. Regards Oliver