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    SubjectRe: getting timestamp of last interrupt?
    Richard B. Johnson wrote:

    > On Mon, 6 Oct 2003, Hans-Georg Thien wrote:
    >
    >>
    >>[...]
    >>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
    >
    >
    > Then it gets real simple. Just use jiffies, if you can stand the [...]
    I fear that there is still some miss-understanding. Jiffies are totally
    OK for me. I can use them without any conversion.

    I'll try to formulate the problem with some other words:

    I hope that there is is something like a "jiffie-counter" for the
    keyboard driver, that stores the actual jiffies value whenever a
    keyboard interrupt occurs.

    I hope too, that there is a way to query that "jiffie-counter" from
    another kernel driver, so that I can write something like


    mymouse_module.c

    ...
    void mouse_event(){

    // get the current time in jiffies
    int now=jiffies;

    // get the jiffie value of the last kbd event
    int last_kbd_event= ????; // ... but how to do that ...

    if ((now - last_kbd_event) > delay) {
    do_some_very_smart_things();
    }
    }
    ...

    -Hans


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