From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: 2.6.25-rc2 System no longer powers off after suspend-to-disk. Screen becomes green. Date: Thu, 21 Feb 2008 01:13:04 +0100 Message-ID: <200802210113.05733.rjw@sisk.pl> References: <200802210035.14058.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: suspend-devel-bounces@lists.sourceforge.net Errors-To: suspend-devel-bounces@lists.sourceforge.net To: Linus Torvalds Cc: Jeff Chua , Alexey Starikovskiy , Dave Airlie , Greg KH , lkml , suspend-devel List , linux-acpi@vger.kernel.org, Jesse Barnes List-Id: linux-acpi@vger.kernel.org On Thursday, 21 of February 2008, Linus Torvalds wrote: > > On Thu, 21 Feb 2008, Rafael J. Wysocki wrote: > > > > In fact we have acpi_pci_choose_state() that tells the driver which power > > state to put the device into in ->suspend(). If that is used, the device ends > > up in the state expected by to BIOS for S4. > > First off, nobody should *ever* use that directly anyway. Yes, sorry. > Secondly, the one that people should use ("pci_choose_state()") doesn't > actually do what you claim it does. It does all kinds of wrong things, and > doesn't even take the target state into account at all. So look again. Well, if platform_pci_choose_state() is defined, pci_choose_state() returns its result and on ACPI systems that points to acpi_pci_choose_state(), so in fact it does what I said (apart from the error path). > > No. Again, if there are devices that wake us up from S4, but not from S5, > > they need to be handled differently in the *enter S4* case (hibernation) and > > in the *enter S5* case (powering off the system). > > And again, what does this have to do with (the example I used) the > graphics hardware? Answer: nothing. The example I gave you we simply DO > THE WRONG THING FOR. > > Same thing for things like USB devices - where pci_choose_state() doesn't > work to begin with. Why do we call "suspend()" on such a thing when we > don't want to suspend it? We shouldn't. We should call "freeze/unfreeze" > (which are no-ops) and then finally perhaps "poweroff", and that final > stage might want to spin things down or similar. I'm already convinced, really. :-) Thanks, Rafael ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/