Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934288AbZJGQff (ORCPT ); Wed, 7 Oct 2009 12:35:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934245AbZJGQfd (ORCPT ); Wed, 7 Oct 2009 12:35:33 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:35057 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S933702AbZJGQfc (ORCPT ); Wed, 7 Oct 2009 12:35:32 -0400 Date: Wed, 7 Oct 2009 12:34:55 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Oliver Neukum cc: Alan Cox , , , Subject: Re: [PATCH 4/5] usb_serial: Kill port mutex In-Reply-To: <200910071810.02966.oliver@neukum.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1084 Lines: 26 On Wed, 7 Oct 2009, Oliver Neukum wrote: > Am Mittwoch, 7. Oktober 2009 18:03:08 schrieb Alan Stern: > > On Wed, 7 Oct 2009, Oliver Neukum wrote: > > > We will need some generic way to autoresume from open. > > > Resume will need to lock against open() and need to be called > > > from within open(). Any ideas for an unugly interface? > > > > It's not quite that bad. ?Resume doesn't need to lock against open. > > If open is called while resume is running then when it tries to do its > > own resume, it will either block (waiting for the pm_mutex) or return > > immediately (if it sees the device is already resumed). > > But resume() needs to know whether the read URBs need to be > submitted or not. Given that there are several pathways for turning on or turning off the read URBs, the best answer is to use a flag. Alan Stern -- 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/