From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH 2/2] ata_piix: fix suspend/resume for some TOSHIBA laptops Date: Tue, 24 Jul 2007 18:05:55 -0400 Message-ID: <46A677C3.9090107@garzik.org> References: <20070710063605.GA21994@htj.dyndns.org> <20070710065543.GA23568@htj.dyndns.org> <46A66842.6040803@garzik.org> <20070724225747.1dd4d141@the-village.bc.nu> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:59796 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755079AbXGXWF7 (ORCPT ); Tue, 24 Jul 2007 18:05:59 -0400 In-Reply-To: <20070724225747.1dd4d141@the-village.bc.nu> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Alan Cox Cc: Tejun Heo , greg@kroah.com, linux-ide@vger.kernel.org, owner-linux-pci@atrey.karlin.mff.cuni.cz Alan Cox wrote: >> A more generalized rule to consider for the future would be to ensure >> that ALL suspend routines put the hardware back into its pre-Linux init >> mode before suspending. i.e. that means if we turned on some enhanced >> mode, we must switch back to legacy mode before calling pci_xxx to >> suspend our device. > > This sounds good but for some hardware you can't get it back into that > state and there is no guarantee some laptops don't have ACPI suspend > paths that "know" Windows will have reconfigured the hardware. Good point. To generalize a bit more: it is quite possible that many situations will require us to put the hardware device into a certain mode before suspending, a mode that Linux may not currently be operating in. ata_piix is definitely not going to be the only one needing this change, long term. Jeff