Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757623AbZDUQyB (ORCPT ); Tue, 21 Apr 2009 12:54:01 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756097AbZDUQwn (ORCPT ); Tue, 21 Apr 2009 12:52:43 -0400 Received: from sj-iport-6.cisco.com ([171.71.176.117]:19766 "EHLO sj-iport-6.cisco.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757195AbZDUQw2 (ORCPT ); Tue, 21 Apr 2009 12:52:28 -0400 X-IronPort-AV: E=Sophos;i="4.40,225,1238976000"; d="scan'208";a="290188159" Date: Tue, 21 Apr 2009 09:52:14 -0700 From: David VomLehn To: Alan Stern Cc: Jamie Lokier , Ingo Molnar , Arjan van de Ven , "H. Peter Anvin" , Thomas Gleixner , Linus Torvalds , Linux Kernel Mailing List , Linux USB Mailing List , Linux Embedded Mailing List , Andrew Morton Subject: Re: Wait for console to become available, v3.2 Message-ID: <20090421165214.GB8251@cuplxvomd02.corp.sa.net> References: <20090421140533.GA6375@shareable.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) Authentication-Results: sj-dkim-2; header.From=dvomlehn@cisco.com; dkim=pass ( sig from cisco.com/sjdkim2002 verified; ); Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1210 Lines: 25 > If somebody would like to suggest a programming interface (a waitqueue > perhaps?) by which the USB hub driver could send a notification when it > becomes idle, I could implement it. I actually started the USB console stuff with exactly this approach, but switched to the approach that's out there. A minor drawback, which is probably obvious, is that you actually wait for some interval without getting anything to do before you think things are idle. But a bigger drawback is that you lose the ability to chose appropriate intervals for different classes of devices. So far, there appear to be three possible USB boot devices: consoles, network devices, and boot devices. A system may not have all of these and so may not need to wait as long as a system with all of them. One of my goals is to preserve as much of the reduction in boot time as possible, even on systems that use USB devices that may or may not be plugged in. > Alan Stern David VomLehn -- 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/