From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael Frank" Subject: Re: Re: [Swsusp-devel] swsusp and ac status Date: Mon, 28 Jun 2004 08:13:00 +0800 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: References: <200406250701.i5P71GKC006204@fermat.unipv.it> <20040627222842.GB1816@hell.org.pl> Mime-Version: 1.0 Content-Type: text/plain; format=flowed; delsp=yes; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20040627222842.GB1816-DETuoxkZsSqrDJvtcaxF/A@public.gmane.org> Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Karol Kozimor Cc: Daniele Boffi , acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Software Suspend - Mailing Lists List-Id: linux-acpi@vger.kernel.org On Mon, 28 Jun 2004 00:28:42 +0200, Karol Kozimor wr= ote: > Thus wrote Michael Frank: >> Too bad, this implies that the AC module does not get reinitialized af= ter >> resume and I suspect that acpi core is broken on 2.6 in this regard. > > As far as I know, there is no need to reinitialize the AC module, as it > does not cache the results -- upon read, it calls the appropriate _PSR > method which is supposed to return the correct AC adapter state, as sim= ple > as it gets. This way, any problems would indicate a faulty BIOS. > Best regards, > Sorry, the BIOS does not know about suspend. Please consider It just booted cold and the resuming kernel without any ACPI modules won't have touched the AC method. ----> Thus the BIOS is now in a post boot state, like before vmlinux starts on boot! ----> The resumed kernel is in the state it was upon suspend. Therefor IMO cause is the kernel which was resumed and continues to talk to the BIOS which is in a state quite different than what it was pefore suspend... I concur that the BIOS in this case may break, but as it worked prior to suspend it cannot be blamed for not handling such abuse. A simple solution is for the resumed kernel to start talking to BIOS as it would have on a normal boot, perhaps executing just a subset of the init code. If it also would disable all modules prior to suspend, it would likely fix all problems eliminating the reuqirement to unload ACPI modules.... Best Regards ------------------------------------------------------- This SF.Net email sponsored by Black Hat Briefings & Training. Attend Black Hat Briefings & Training, Las Vegas July 24-29 - digital self defense, top technical experts, no vendor pitches, unmatched networking opportunities. Visit www.blackhat.com