From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932305AbWFSUwK (ORCPT ); Mon, 19 Jun 2006 16:52:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932318AbWFSUwK (ORCPT ); Mon, 19 Jun 2006 16:52:10 -0400 Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:682 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S932305AbWFSUwI (ORCPT ); Mon, 19 Jun 2006 16:52:08 -0400 Subject: Re: Linux 2.6.17: IRQ handler mismatch in serial code? From: Alan Cox To: Mark Lord Cc: Chris Rankin , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org In-Reply-To: <4496FEC2.8050903@rtr.ca> References: <20060619180658.58945.qmail@web52908.mail.yahoo.com> <20060619184706.GH3479@flint.arm.linux.org.uk> <4496FEC2.8050903@rtr.ca> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Mon, 19 Jun 2006 22:06:52 +0100 Message-Id: <1150751212.2871.44.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.6.2 (2.6.2-1.fc5.5) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Ar Llu, 2006-06-19 am 15:45 -0400, ysgrifennodd Mark Lord: > If the drivers are written "correctly", they shouldn't grab the IRQ > until someone actually opens the device. Which means they should be > able the share the IRQ, so long as both devices are not in use (open) > at the same time. This is not the case for ISA bus. Most ISA hardware is physically unable to share and the drivers for such hardware intentionally grab the IRQ at load time to avoid it being mis-reused. Alan