From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757980AbcILLrV (ORCPT ); Mon, 12 Sep 2016 07:47:21 -0400 Received: from lxorguk.ukuu.org.uk ([81.2.110.251]:60398 "EHLO lxorguk.ukuu.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756103AbcILLrT (ORCPT ); Mon, 12 Sep 2016 07:47:19 -0400 Date: Mon, 12 Sep 2016 12:46:55 +0100 From: One Thousand Gnomes To: Rob Herring Cc: Alan Cox , Greg Kroah-Hartman , Jiri Slaby , Peter Hurley , "linux-kernel@vger.kernel.org" , "linux-serial@vger.kernel.org" Subject: Re: [PATCH 0/9] tty: tty_struct dependency clean-ups Message-ID: <20160912124655.6a698da0@lxorguk.ukuu.org.uk> In-Reply-To: References: <20160909223711.26238-1-robh@kernel.org> <20160911221424.2d56682a@lxorguk.ukuu.org.uk> Organization: Intel Corporation X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 11 Sep 2016 22:05:07 -0500 Rob Herring wrote: > On Sun, Sep 11, 2016 at 4:14 PM, One Thousand Gnomes > wrote: > > On Fri, 9 Sep 2016 17:37:01 -0500 > > Rob Herring wrote: > > > >> This patch series removes or prepares to remove some of the dependencies > >> on tty_struct within tty_port drivers. This will allow using tty_ports > >> directly for so called UART slave devices. > > > > You can create a tty_struct kernel side with the two tiny changes I > > posted before. Why do you want to do invasive tree wide changes when you > > can do simple ones ? > > Well, I don't want to do invasive changes, but I thought the idea was > to use tty_port struct without a tty_struct. I posted some tiny patches to break the file/tty requirement in the base tty code for comment a while ago and they were very tiny for most ldiscs (n_tty unsurprisingly wouldn't work this way but does anyone need kernel mode n_tty ?) Moving termios into the tty_port is IMHO a good thing to do whichever approach is taken. > I was planning to keep termios out of tty_port and make clients of > tty_port carry it if for nothing else not quite understanding all the > details around the lifetime, init and locking of it. If there's always > a tty_struct then there's not much point moving it other than which > struct makes more sense. But that would cause some churn. The termios lifetime is the lifetime of the port, although it may get reset at some times. Alan