Re: getting timestamp of last interrupt?

[Hans-Georg Thien]

Richard B. Johnson wrote:
> On Sat, 4 Oct 2003, Hans-Georg Thien wrote:
>
>
> > > [...]
> > > > I am looking for a possibility to read out the last timestamp when an
> > > > interrupt has occured.
> > > >
> > > > e.g.: the user presses a key on the keyboard. Where can I read out the
> > > > timestamp of this event?
> > >
> > >
> > > You can get A SIGIO signal for every keyboard, (or other input) event.
> > > What you do with it is entirely up to you. Linux/Unix doesn't have
> > > "callbacks", instead it has signals. It also has select() and poll(),
> > > all useful for handling such events. If you want a time-stamp, you
> > > call gettimeofday() in your signal handler.
> >
> > Thanks a lot Richard,
> >
> > ... but ... can I use signals in kernel mode?
>
>
> Well you talked about the user pressing a key and getting
> a time-stamp as a result. If you need time-stamps
> inside the kernel, i.e, a module, then you can call
> the kernel's do_gettimeofday() function.
Hello Richard, - It seems, that I should be more precise about what I 
exactly mean...


I'm writing a kernel mode device driver (mouse).

In that device driver I need the timestamp of the last event for another 
kernel mode device (keyboard).

I do not care if that timestamp is in jiffies or in gettimeofday() 
format or whatever format does exist in the world. I am absolutely sure 
I can convert it somehow to fit my needs.

But since it is a kernel mode driver it can not -AFAIK- use the signal() 
syscall.

-Hans



-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/