[lkml]   [2012]   [Apr]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [PATCH ] leds: add new transient trigger for one shot timer support
    Hi Jonas,

    activate does sound better and having units in the property name is a
    good idea. Will make the changes including the 0200 change for activate.
    Will change the transient_time to transient_time_msec (no problem using
    duration, just that time is shorter :)

    > A couple of questions:
    > i) Why is it important for you to maintain the LED state?
    One use-case that would be easier for user to comprehend would be to
    have a constant timer that runs periodically. time value doesn't change
    and by simply writing 1 or 0, timer with a value specified by the time
    file can be started. The following use-case is a good example for what I
    am talking about:

    echo transient > trigger
    echo n > transient_time
    repeat the following step as needed:
    echo 1 > transient_enabled - start timer = transient_time to run once
    echo 1 > transient_enabled - start timer = transient_time to run once
    echo none > trigger

    This could be accomplished by simply using just the time property,
    however, each time, the same timer value needs to be echoed. Not a big
    deal, however time value either needs to stay where it is even when a
    timer is not running, or clear it 0. I don't like clearing the time
    value. Here is why. The use-case is very similar to a stop and start
    timer function on a watch for example. I typically set a time
    value and then activate and deactivate as needed without needing to
    reset the time value.

    > ii) Why do you need to be able to cancel the timer?
    Here is an example where canceling timer is necessary. Phone is in
    silent mode and a call comes in. When call comes in phone will start
    vibrating (maybe vibrate mode set for 2 seconds), when caller answers,
    vibrate mode needs to deactivated right away by stopping the vibrate
    mode and canceling the timer.
    > As I understand this trigger (and your use-case), this is about being
    > able to turn on a LED (signal) and forget about it, knowing that it will
    > be extinguished in due time without any intervention. So I would leave
    > it at that; don't even present an option to intervene.
    > That said, there is already a way to intervene: I can always write 0 to
    > 'brightness' to extinguish the led immediately.

    That is correct. brightness could be used, however having a distinct
    name-space might be better for future changes instead of overloading

    Hope this helps explain my reasoning to keep transient state.

    -- Shuah

     \ /
      Last update: 2012-04-23 01:55    [W:0.026 / U:30.588 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site