Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751601AbWBQUCU (ORCPT ); Fri, 17 Feb 2006 15:02:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751583AbWBQUCU (ORCPT ); Fri, 17 Feb 2006 15:02:20 -0500 Received: from caramon.arm.linux.org.uk ([212.18.232.186]:52235 "EHLO caramon.arm.linux.org.uk") by vger.kernel.org with ESMTP id S1751589AbWBQUCT (ORCPT ); Fri, 17 Feb 2006 15:02:19 -0500 Date: Fri, 17 Feb 2006 20:02:13 +0000 From: Russell King To: linux-kernel@vger.kernel.org Subject: Re: [PATCH] SIIG 8-port serial boards support Message-ID: <20060217200213.GA13502@flint.arm.linux.org.uk> Mail-Followup-To: linux-kernel@vger.kernel.org References: <20060124082538.GB4855@pazke> <20060124210140.GB23513@flint.arm.linux.org.uk> <20060202102644.GC5034@flint.arm.linux.org.uk> <20060202132726.GD24903@pazke> <20060202201734.GA17329@flint.arm.linux.org.uk> <20060203091308.GA19805@pazke> <20060203092435.GA30738@flint.arm.linux.org.uk> <20060217113942.GA30787@pazke> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060217113942.GA30787@pazke> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2163 Lines: 51 On Fri, Feb 17, 2006 at 02:39:42PM +0300, Andrey Panin wrote: > On 034, 02 03, 2006 at 09:24:36 +0000, Russell King wrote: > > On Fri, Feb 03, 2006 at 12:13:08PM +0300, Andrey Panin wrote: > > > On 033, 02 02, 2006 at 08:17:35 +0000, Russell King wrote: > > > > As I've said many a time, we need a generic way to set different hand- > > > > shaking modes. I've suggested using some spare bits in termios in the > > > > past, but nothing ever came of that - folk lose interest at that point. > > No wonder they do. Extra bits are not a problem, but for 8250.c we need some > way to glue subdrivers with serial8250_set_termios(). Callback in uart_port > structure ? They lose interest because they want to solve only their own small little problem without looking at the bigger picture. That's not what I'm interested in, so as far as I'm concerned (and I hope this is clear) I have _zero_ interest in solving their small little problems. By only solving the small little problem, we end up with lots of drivers doing their own stupid implementation of the same feature, which results in multiple differing ways to enable said same feature from userspace. Plus, there is more to handshaking than just the standard protocol we implement today - yes there's RS485-using-RTS flavour, but there's also an alternative interpretation of RTS to mean "I am requesting to send something" rather than the conventional "it is okay for you to send me something". And yes, someone has already requested this alternative RTS interpretation. So, there are three distinct flow control scenarios: - conventional RTS/CTS - alternative RTS/CTS - RS485 As I've said above, if folk wish to bury their heads and just address RS485 in isolation, I'm just plain not interested. Let's do the job properly or not at all. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 Serial core - 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/