From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Madore Subject: Re: Reboot on shutdown with USB 2.0 Date: Fri, 28 Mar 2003 15:41:08 -0800 Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Message-ID: <3E84DD94.4080508@aslab.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Help: List-Post: List-Subscribe: , List-Unsubscribe: , List-Archive: To: "Grover, Andrew" Cc: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Grover, Andrew wrote: >>From: Michael Madore [mailto:mmadore-JChM1cqIHx8AvxtiuMwx3w@public.gmane.org] >> >> > > > >>I'm having a strange problem regarding ACPI and USB 2.0 devices >>(External CD-Rom, Jaz drive, etc). Using 2.4.21-pre5 with the latest >>patch if I issue: >> >>shutdown -h now >> >>The machine shuts off, but half a second later the power >>comes back on. >> If I unload the echi driver module, the machine shuts off normally. >> >>Any thoughts on what would cause that kind of behavior? >> >> > >Is this an SMP system? Just curious. > > Yes, this particular system is SMP. I'll have to try it with a UP kernel just to see if the problem persists. >What we should be doing (but aren't) is telling each device's driver on >the system to deactivate its device before we turn off the system power. >This gives the driver the chance to disable that device's interrupt >generation. We haven't gotten that far in the driver model work, so what >we are doing is disabling interrupts and then powering down. This mostly >works, but isn't really how we want things to work, and is pretty much >doomed to fail on SMP systems. > >I don't know why the ehci device would specifically be the one to cause >problems... > > That makes sense, thanks for the explaination. As a workaround, perhaps we can modify the init scripts to unload the ehci driver during shutdown. Mike Madore ------------------------------------------------------- This SF.net email is sponsored by: The Definitive IT and Networking Event. Be There! NetWorld+Interop Las Vegas 2003 -- Register today! http://ads.sourceforge.net/cgi-bin/redirect.pl?keyn0001en