From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754141AbYE3WIk (ORCPT ); Fri, 30 May 2008 18:08:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751340AbYE3WIc (ORCPT ); Fri, 30 May 2008 18:08:32 -0400 Received: from smtpq1.groni1.gr.home.nl ([213.51.130.200]:56746 "EHLO smtpq1.groni1.gr.home.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751185AbYE3WIb (ORCPT ); Fri, 30 May 2008 18:08:31 -0400 Message-ID: <48407B99.4080209@keyaccess.nl> Date: Sat, 31 May 2008 00:11:37 +0200 From: Rene Herman User-Agent: Thunderbird 2.0.0.14 (X11/20080421) MIME-Version: 1.0 To: Bjorn Helgaas CC: Takashi Iwai , Alan Cox , Linux Kernel , ALSA devel , Andrew Morton Subject: Re: [PATCH] Re: 2.6.26-rc1 regression: ISA DMA broken (bisected) References: <4823AAF2.7070102@keyaccess.nl> <482B38D6.5030804@keyaccess.nl> <48406E8D.8050408@keyaccess.nl> <200805301543.42208.bjorn.helgaas@hp.com> In-Reply-To: <200805301543.42208.bjorn.helgaas@hp.com> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -1.0 (-) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 30-05-08 23:43, Bjorn Helgaas wrote: > On Friday 30 May 2008 03:15:57 pm Rene Herman wrote: >> It gets uglier. ALSA ISA drivers (for cards that exist both as legacy >> and as ISAPnP at least) keep a merged legacy/isapnp model; PnP is used >> mostly for initializing global variables that the same old legacy probe >> routines then reference. This means that beyond that global resource >> init step the specific struct device is no longer available. Without >> restructuring too many things really only fixable through other hacks >> again such as a global dma_dev[] array or some such. >> >> From the viewpoint of PnP itself setting the dma_mask for a pnp_card (a >> pnp_dev collection) makes isolated sense so if no objections, I'll >> submit the attached after all. From the ALSA side we'd then pass the >> card dev (which we'd also do for isa_dev) and keep in mind that we might >> want to get more specific if over time structure permits it. >> >> struct snd_pcm already has its own struct device * which would be the >> right one here but it's setting that which gets ugly... > > Looks good to me. It does sound like a lot of work and possibly > more risk than it's worth to fix up some of this stuff. Fairly invasive at least. The good thing though is that with the recent pnp_manual_config_dev() removal the PnP drivers have no actual need/use for this global variable model anymore and now I have a great excuse for rewriting them. That can happen one at a time though... > I do still wonder whether any non-x86 architectures need similar > fixes in dma_alloc_coherent(), i.e., check for dev==NULL and fall > back to a 24-bit DMA mask. Hrmmpf. Good question. In sound/isa, we've had a but of alpha spottyness over time but nothing which would seem to be related. > Acked-by: Bjorn Helgaas Thanks. I'll assume Andrew picks it up from the CC... Rene.