From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Hurley Subject: Re: [Gta04-owner] [PATCH 0/3] tty slave device support - version 3. Date: Thu, 07 May 2015 11:37:57 -0400 Message-ID: <554B86D5.8080403@hurleysoftware.com> References: <20150318055437.21025.13990.stgit@notabene.brown> <55492001.30806@hurleysoftware.com> <20150506092738.GB4508@amd> <554A03A7.2000504@hurleysoftware.com> <20150506123632.GA1764@leverpostej> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org 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" List-Id: devicetree@vger.kernel.org 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? >=20 > In OO terminology: =E2=80=9Edevice connects to uart=E2=80=9C vs. =E2=80= =9Euart has device connected=E2=80=9C. > "d -> u=E2=80=9C vs. "u <- d=E2=80=9C. 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 ho= st) 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