From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261768AbVFPQHB (ORCPT ); Thu, 16 Jun 2005 12:07:01 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261772AbVFPQHA (ORCPT ); Thu, 16 Jun 2005 12:07:00 -0400 Received: from caramon.arm.linux.org.uk ([212.18.232.186]:17679 "EHLO caramon.arm.linux.org.uk") by vger.kernel.org with ESMTP id S261768AbVFPQG1 (ORCPT ); Thu, 16 Jun 2005 12:06:27 -0400 Date: Thu, 16 Jun 2005 17:06:22 +0100 From: Russell King To: Pierre Ossman Cc: LKML , Alan Cox Subject: Re: ISA DMA controller hangs Message-ID: <20050616170622.A1712@flint.arm.linux.org.uk> Mail-Followup-To: Pierre Ossman , LKML , Alan Cox References: <42987450.9000601@drzeus.cx> <1117288285.2685.10.camel@localhost.localdomain> <42A2B610.1020408@drzeus.cx> <42A3061C.7010604@drzeus.cx> <42B1A08B.8080601@drzeus.cx> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: <42B1A08B.8080601@drzeus.cx>; from drzeus-list@drzeus.cx on Thu, Jun 16, 2005 at 05:53:47PM +0200 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 16, 2005 at 05:53:47PM +0200, Pierre Ossman wrote: > So how do we solve this problem? We should do a master clear and then > enable channel 4 after a suspend. The question is where. I see three > possible places: > > * In the suspend code in kernel/power. > * In the driver actually handling the suspend (ACPI/APM/etc.). > * Via the device layer by adding a device for the DMA controller. > > Which would be the preferred solution? Shouldn't there be a system device for the DMA controller? I think that should have appropriate hooks into the power management system to do the necessary magic to restore whatever's needed - just like we do for the PIC. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 Serial core