Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934257AbZJGQDq (ORCPT ); Wed, 7 Oct 2009 12:03:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934196AbZJGQDq (ORCPT ); Wed, 7 Oct 2009 12:03:46 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:33058 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S932780AbZJGQDp (ORCPT ); Wed, 7 Oct 2009 12:03:45 -0400 Date: Wed, 7 Oct 2009 12:03:08 -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: <200910070702.32266.oliver@neukum.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 860 Lines: 21 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). A more interesting question is how to synchronize both open/close and suspend/resume against throttle/unthrottle. 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/