From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhang Rui Subject: Re: [patch 2.6.21-rc5-git] make /proc/acpi/wakeup more useful Date: Mon, 09 Apr 2007 10:36:25 +0800 Message-ID: <1176086185.2650.28.camel@localhost.localdomain> References: <200704031741.42273.david-b@pacbell.net> <200704060843.30723.david-b@pacbell.net> <20070407050131.GB25511@kroah.com> <200704071308.07571.david-b@pacbell.net> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <200704071308.07571.david-b@pacbell.net> Sender: linux-kernel-owner@vger.kernel.org To: David Brownell , Greg KH Cc: Andrew Morton , lenb@kernel.org, "linux-acpi@vger" , Linux Kernel list List-Id: linux-acpi@vger.kernel.org On Sat, 2007-04-07 at 13:08 -0700, David Brownell wrote: > On Friday 06 April 2007 10:01 pm, Greg KH wrote: > > > Are you _sure_ you have a 1-to-1 relationship here? No multiple devices > > pointing to the same acpi node? Or the other way around? If so, you > > are going to have to change the name to be something more unique. > > I've wondered that too. The short answer: APCI only supports 1-1 > here. Right. > It will emit warnings if it tries to bind more than one ACPI > device to a given "real" device ... but errors the other way are > silently ignored. > My understanding is different. First, one "real" device can only have one device.archdata.acpi_handle, which means it can only be bound to one ACPI device. Second, AE_ALREADY_EXISTS will be returned when ACPI tries to bind more than one "real" devices to the same ACPI device. > By adding a warning over this create-links patch, I found that the > system in the $SUBJECT patch (and likely every ACPI system) has > two different nodes that correspond to one ACPI node: > > /sys/devices/pci0000:00 ... pci root node > /sys/devices/pnp0/00:00 ... id PNP0a03 > /sys/devices/acpi_system:00/device:00/PNP0A03:00 ... ditto > > Arguably that's too many sysfs nodes for one device... > > Plus, there's the issue of flakey ACPI tables; in the $SUBJECT patch > both MDM and AUD nodes exist in the ACPI namespace, but they could > only refer to one PCI device (with MDM as the wakeup source, not AUD > as listed in the table). Or maybe that's another case where the ACPI > code isn't handling the tables as sensibly as it might... > Could you attach this acpidump please? :) Thanks, Rui