Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752886Ab0LGR3p (ORCPT ); Tue, 7 Dec 2010 12:29:45 -0500 Received: from mtagate5.uk.ibm.com ([194.196.100.165]:33899 "EHLO mtagate5.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751853Ab0LGR3o (ORCPT ); Tue, 7 Dec 2010 12:29:44 -0500 Date: Tue, 7 Dec 2010 18:29:37 +0100 (CET) From: Sebastian Ott X-X-Sender: sebott@localhost6.localdomain6 To: Greg KH cc: Kay Sievers , linux-kernel@vger.kernel.org Subject: Re: [RFC] bind/unbind uevent In-Reply-To: <20101207162755.GA32328@suse.de> Message-ID: References: <20101207162755.GA32328@suse.de> User-Agent: Alpine 2.02 (LFD 1266 2009-07-14) Organization: "IBM Deutschland Research & Development GmbH Vorsitzender des Aufsichtsrats: Martin Jetter Geschaeftsfuehrung: Dirk Wittkopp Sitz der Gesellschaft: Boeblingen Registergericht: Amtsgericht Stuttgart, HRB 243294" 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: 1912 Lines: 48 On Tue, 7 Dec 2010, Greg KH wrote: > On Tue, Dec 07, 2010 at 05:18:27PM +0100, Sebastian Ott wrote: > > Hi, > > > > There is currently no generic trigger for userspace to know when a driver > > is bound to a device. > > Not true at all, you get one when a device is attached to a bus. What's > wrong with that notification? we get a KOBJ_ADD if a device is attached to a bus, but this does not imply that a device driver is bound to this device > > > Such a trigger may be required in cases where setup > > steps must be performed in userspace after the device is bound, e.g. > > because the driver adds sysfs attributes in its probe function. > > A driver should not add sysfs attributes in its probe function as that > is racy as you have noticed. Add the attributes in the bus functions > for that driver and it should be fine. sry..I was not clear on this one. I was talking driver specific attributes per device. So I'm searching for a trigger when these attributes are created, or in other words when the device is useable, which I think translates to when a driver is bound to this device. > > > I can imagine 3 possible ways to solve this problem: > > * add a bus specific change event (triggered by BUS_NOTIFY_BOUND_DRIVER) > > - this may result in duplicated code for each bus > > * dissable autoprobing and "manually" probe the device from userspace > > triggered by the add event - this duplicates logic already implemented > > in the kernel > > * add a generic bind/unbind uevent > > > > Which one is preferred from a driver core perspective? > > None, use the existing notifications like everyone else :) > > thanks, > > greg k-h > -- 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/