From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bjorn Helgaas Subject: Re: [2.6.23-rc3 possible regression] 8250 claims nonexisting device blocking IO port Date: Fri, 24 Aug 2007 12:33:55 -0600 Message-ID: <200708241233.55698.bjorn.helgaas@hp.com> References: <200708181107.56087.arvidjaar@mail.ru> <200708211334.58157.bjorn.helgaas@hp.com> <200708242142.37001.arvidjaar@mail.ru> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Return-path: Received: from atlrel7.hp.com ([156.153.255.213]:57541 "EHLO atlrel7.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756732AbXHXSeS (ORCPT ); Fri, 24 Aug 2007 14:34:18 -0400 In-Reply-To: <200708242142.37001.arvidjaar@mail.ru> Content-Disposition: inline Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: Andrey Borzenkov Cc: linux-serial@vger.kernel.org, Michal Piotrowski , linux-kernel@vger.kernel.org On Friday 24 August 2007 11:42:36 am Andrey Borzenkov wrote: > On Tuesday 21 August 2007, Bjorn Helgaas wrote: > > On Tuesday 21 August 2007 12:28:49 pm Andrey Borzenkov wrote: > > > On Monday 20 August 2007, Bjorn Helgaas wrote: > > > > On Monday 20 August 2007 10:28:22 am Andrey Borzenkov wrote: > > > > > This worked in 2.6.22 with the same quirks. I will test without later > > > > > but I fail to see how they are related. > > > > > > > > OK, let me know what happens. The way it's related is that the quirk > > > > fiddles with the IRDA device, and it probably changes the SIR config > > > > so that it starts responding at the ttyS3 address. > > > > > > You are probably right. Disabling quirk makes it work again (with pnp off > > > in smsc-ircc2 of course). > > > > I think pnp is off in smsc-ircc2 by default, right? > > > > > Hmm ... is there any reason why this quirk is in PnP core in the first > > > place? Would not it be more logical to have it in (PnP) part of > > > smsc-ircc2? This way it could share code with legacy detection; and it > > > even may have chance to work - assuming BIOS is aware that 0x100 is > > > claimed by PCMCIA it could allocate different port when we try to > > > activate device after that ... should I give it a try? > > > > I agree it would make sense to put the quirk in smsc-ircc2, since > > we only need it if we want to use the smsc-ircc2 driver. But I don't > > think we have a mechanism for calling quirks at module load-time, so > > it has to be part of the static kernel. And we don't have anything > > like DECLARE_PCI_FIXUP_SECTION, so it really has to be in quirks.c for > > now. > > > > How does the following patch look? > > > I am fine with any patch that works. Of course, it would be better to fix 8250 > to respect PnP (it does load 8250_pnp in the first place). I agree. 8250_pnp is actually fine -- it won't claim SMCf010 devices. The problem is that we have the legacy addresses (including the SMCf010 SIR range) in SERIAL_PORT_DFNS, so 8250.c claims the SIR range in serial8250_isa_init_ports(). I'm still hoping to fix that bit of 8250, but it's going to take some work. I'll post the SMCf010 quirk removal as a fix for the 2.6.23-rc3 regression. Bjorn