Messages in this thread |  | | Date | Wed, 3 Sep 2008 10:26:30 -0400 | | From | Dmitry Torokhov <> | | Subject | Re: Lenovo 3000 N100 i8042 problems |
| |
On Tue, Sep 02, 2008 at 12:16:15PM -0400, Daniel Barkalow wrote: > On Tue, 2 Sep 2008, Dmitry Torokhov wrote: > > > On Tue, Sep 02, 2008 at 11:23:25AM +0200, Jiri Kosina wrote: > > > > > > so the product name both of System and Base Board are different, and > > > apparently the systems differ. Dmitry, what fields would you propose to be > > > put in the DMI matching here? I will do the patch then. > > > > > > > I guess we could use System's product name to differentiate between > > Cristopher's and Daniel's boards. Although I must admit it is the very > > first time when I see a box that behaves better with active mux. DOes > > Vista use active mux nowadays? Because if it is not then I bet there > > is (or shortly will be) a BIOS update fixing legacy mode on Daniel's > > box. > > Mine's actually old (came with XP). It's still got the original BIOS > (because I haven't found a way to upgrade the BIOS without reformatting my > hard drive to include Windows), and I remember there being an upgrade > available, but I don't think it had anything to do with keyboard/trackpad > stuff. > > In what way does active mux usually behave badly? It's possible that
It usually manifests with a touchpad/mouse missing because they don't responf to kernel's queries. Quite a few Fujitsus exibit this behavior.
> legacy mode only has a bug that doesn't matter to Windows, and active mux > may have some of the usual problems but nothing I particularly noticed. > > I noticed that, when my i8042 would stop working, it would generally have > just delivered one mouse interrupt to CPU1 after never previously doing > so. Perhaps there's some sort of deadlock in the Linux i8042 driver when > both cores are unexpectedly getting interrupts from the two devices at > once? I could understand there being a Linux bug only triggered by quirky > hardware that only applies to legacy mode, which was just uncovered by > this patch. >
I am not sure, internally we the kernel still deals with 2 interrupt sources (KBD and AUX) regardless whether it is in legacy or active multiplexing mode...
Does it take long to trigger the bug? You coudl try doing "echo 1 > /sys/modules/i8042/parameters/debug" and thend me dmesg or /var/log/messages after the bug was triggered - I might see something there. But please be aware that if you send me such a log I can decode everything that you have been typing...
-- Dmitry
|  |