Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752125AbbEGPiL (ORCPT ); Thu, 7 May 2015 11:38:11 -0400 Received: from mail-qg0-f46.google.com ([209.85.192.46]:34132 "EHLO mail-qg0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751442AbbEGPiF (ORCPT ); Thu, 7 May 2015 11:38:05 -0400 Message-ID: <554B86D5.8080403@hurleysoftware.com> Date: Thu, 07 May 2015 11:37:57 -0400 From: Peter Hurley User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: "Dr. H. Nikolaus Schaller" , Mark Rutland CC: Pavel Machek , List for communicating with real GTA04 owners , NeilBrown , One Thousand Gnomes , Arnd Bergmann , Greg Kroah-Hartman , Sebastian Reichel , "grant.likely@linaro.org" , Jiri Slaby , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [Gta04-owner] [PATCH 0/3] tty slave device support - version 3. References: <20150318055437.21025.13990.stgit@notabene.brown> <55492001.30806@hurleysoftware.com> <20150506092738.GB4508@amd> <554A03A7.2000504@hurleysoftware.com> <20150506123632.GA1764@leverpostej> In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1066 Lines: 28 On 05/06/2015 09:28 AM, Dr. H. Nikolaus Schaller wrote: > The key point appears to be how we want to see the serial connection. Is the > device connected to the uart or the uart to a device? > > In OO terminology: „device connects to uart“ vs. „uart has device connected“. > "d -> u“ vs. "u <- d“. This is not a very good analogy because both relationships need to be represented. The practical consideration is the lifetime of the target device. If the target device should/must have a lifetime (as viewed from the host) outside that of the uart, then the target device should not be a slave device. Object lifetime is controlled by expressions of ownership or scope. Since devicetree offers no expression of ownership, scope is the obvious and natural way to control lifetime. Regards, Peter Hurley -- 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/