From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756605Ab0CXQv5 (ORCPT ); Wed, 24 Mar 2010 12:51:57 -0400 Received: from cantor2.suse.de ([195.135.220.15]:54643 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753808Ab0CXQv4 (ORCPT ); Wed, 24 Mar 2010 12:51:56 -0400 Date: Wed, 24 Mar 2010 09:52:22 -0700 From: Greg KH To: Pavan Savoy Cc: Marcel Holtmann , PavanSavoy , "alan@lxorguk.ukuu.org.uk" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 4/6] drivers:misc: sources for Init manager module Message-ID: <20100324165222.GA9922@suse.de> References: <20100324162616.GA9257@suse.de> <749404.60454.qm@web94909.mail.in2.yahoo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <749404.60454.qm@web94909.mail.in2.yahoo.com> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 24, 2010 at 10:05:19PM +0530, Pavan Savoy wrote: > --- On Wed, 24/3/10, Greg KH wrote: > > > From: Greg KH > > Subject: Re: [PATCH 4/6] drivers:misc: sources for Init manager module > > To: "Marcel Holtmann" > > Cc: "Pavan Savoy" , "PavanSavoy" , "alan@lxorguk.ukuu.org.uk" , "linux-kernel@vger.kernel.org" > > Date: Wednesday, 24 March, 2010, 9:56 PM > > On Wed, Mar 24, 2010 at 09:11:45AM > > -0700, Marcel Holtmann wrote: > > > > I wanted to somehow put this in staging because > > then it would probably have a thorough architectural review > > process. > > > > Some details about this driver - > > > > > > > > 1. This driver will be used by > > Bluetooth-BlueZ/FM-V4L2 and GPS (probably character device > > driver) using the EXPORTED symbols (-register/_unregister). > > > > > > > > 2. Much like the hciattach daemon which maintains > > N_HCI bluetooth line discipline, this driver will also have > > a User-Space? N_TI_WL Init manager (UIM) maintaining > > the Line discipline. > > > > > > can you explain why you think this is needed and we > > can not interface > > > this directly. If it is a serial port, what protocol > > does it talk? > > > > > > > 3. Because of the UIM should know when to > > install/uninstall line discipline, the /sys entry is created > > a root called UIM (a new kobject) and UIM daemon would write > > it's PID to it. > > > > > > I don't understand this. This sounds like a broken > > concept to me. > > > > I also agree, those sysfs files are not acceptable, and > > will not work > > as-designed due to the pid namespace issues :( > > Ok, How do I then from kernel space, ask a user-space daemon to open the TTY port and do a tiocsetd on it ? > [i.e ask for a line discipline to be installed ?] What would cause the kernel to want to tell userspace to do this? Is it an external event that happens somehow that userspace should know to look for? > Can't open the TTY and TIOCSETD upon boot, because BT, FM and GPS > might be used or not used anytime. What causes them to want to be used? The user, right? > And the idea of creating a device node, specifically for this and then > doing an fasync/SIGIO was somehow rubbished. Why? thanks, greg k-h