From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262831AbVF3IBZ (ORCPT ); Thu, 30 Jun 2005 04:01:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262830AbVF3IBZ (ORCPT ); Thu, 30 Jun 2005 04:01:25 -0400 Received: from [85.8.12.41] ([85.8.12.41]:16314 "EHLO smtp.drzeus.cx") by vger.kernel.org with ESMTP id S262831AbVF3IBS (ORCPT ); Thu, 30 Jun 2005 04:01:18 -0400 Message-ID: <42C3A698.9020404@drzeus.cx> Date: Thu, 30 Jun 2005 10:00:24 +0200 From: Pierre Ossman User-Agent: Mozilla Thunderbird 1.0.2-7 (X11/20050623) X-Accept-Language: en-us, en Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="=_hermes.drzeus.cx-24712-1120118477-0001-2" To: LKML CC: Russell King , Alan Cox , Linus Torvalds Subject: Re: ISA DMA controller hangs References: <42987450.9000601@drzeus.cx> <1117288285.2685.10.camel@localhost.localdomain> <42A2B610.1020408@drzeus.cx> <42A3061C.7010604@drzeus.cx> <42B1A08B.8080601@drzeus.cx> <20050616170622.A1712@flint.arm.linux.org.uk> In-Reply-To: <20050616170622.A1712@flint.arm.linux.org.uk> X-Enigmail-Version: 0.90.1.0 X-Enigmail-Supports: pgp-inline, pgp-mime Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org This is a MIME-formatted message. If you see this text it means that your E-mail software does not support MIME-formatted messages. --=_hermes.drzeus.cx-24712-1120118477-0001-2 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 7bit Reset the ISA DMA controller into a known state after a suspend. Primary concern was reenabling the cascading DMA channel (4). Signed-off-by: Pierre Ossman If this patch seems ok then I'll make another one for x86_64 (the only other platform with ISA DMA AFAIK). I couldn't find who was responsible for the i386 arch so I've cc:ed Linus. Rgds Pierre --=_hermes.drzeus.cx-24712-1120118477-0001-2 Content-Type: text/x-patch; name="i8237-i386.patch"; charset=iso-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="i8237-i386.patch" Index: linux-wbsd/arch/i386/kernel/i8237.c =================================================================== --- linux-wbsd/arch/i386/kernel/i8237.c (revision 0) +++ linux-wbsd/arch/i386/kernel/i8237.c (revision 0) @@ -0,0 +1,67 @@ +/* + * i8237.c: 8237A DMA controller suspend functions. + * + * Written by Pierre Ossman, 2005. + */ + +#include +#include + +#include + +/* + * This module just handles suspend/resume issues with the + * 8237A DMA controller (used for ISA and LPC). + * Allocation is handled in kernel/dma.c and normal usage is + * in asm/dma.h. + */ + +static int i8237A_resume(struct sys_device *dev) +{ + unsigned long flags; + int i; + + flags = claim_dma_lock(); + + dma_outb(DMA1_RESET_REG, 0); + dma_outb(DMA2_RESET_REG, 0); + + for (i = 0;i < 8;i++) { + set_dma_addr(i, 0x000000); + /* DMA count is a bit wierd so this is not 0 */ + set_dma_count(i, 1); + } + + /* Enable cascade DMA or channel 0-3 won't work */ + enable_dma(4); + + release_dma_lock(flags); + + return 0; +} + +static int i8237A_suspend(struct sys_device *dev, pm_message_t state) +{ + return 0; +} + +static struct sysdev_class i8237_sysdev_class = { + set_kset_name("i8237"), + .suspend = i8237A_suspend, + .resume = i8237A_resume, +}; + +static struct sys_device device_i8237A = { + .id = 0, + .cls = &i8237_sysdev_class, +}; + +static int __init i8237A_init_sysfs(void) +{ + int error = sysdev_class_register(&i8237_sysdev_class); + if (!error) + error = sysdev_register(&device_i8237A); + return error; +} + +device_initcall(i8237A_init_sysfs); Index: linux-wbsd/arch/i386/kernel/Makefile =================================================================== --- linux-wbsd/arch/i386/kernel/Makefile (revision 153) +++ linux-wbsd/arch/i386/kernel/Makefile (working copy) @@ -7,7 +7,7 @@ obj-y := process.o semaphore.o signal.o entry.o traps.o irq.o vm86.o \ ptrace.o time.o ioport.o ldt.o setup.o i8259.o sys_i386.o \ pci-dma.o i386_ksyms.o i387.o dmi_scan.o bootflag.o \ - doublefault.o quirks.o + doublefault.o quirks.o i8237.o obj-y += cpu/ obj-y += timers/ --=_hermes.drzeus.cx-24712-1120118477-0001-2--