No subject


Wed Feb 22 22:40:10 UTC 2012


structure disappearing so long as the end result is able to do the same
with about the same amount of complexity.

>> Another option to think about... how about putting it in as a generic
>> GPIO - generic PWM bridge and providing one-shot as a degenerate case of
>> that?  Then you can get low latency timed gpio events that's needed and
>> with only very little more code get bitbanged PWM on generic GPIO for
>> low rate DAC action etc.
> 
> A pwm-gpio bridge may well be useful, but I think using that to provide a
> one-shot trigger would be a hack.  Better would be to provide an explicit
> one-shot trigger in some place that already supports triggers...
> 
> 
> (actually, what I really want in an n-shot trigger.

Yeah as I said the degenerate case of it, so a one-shot is just one
cycle of something that becomes pwm if left for more than one cycle.

If the timing / pwm did disappear into gpio plumbing it might be
interesting for LEDs too, it would be able to do soft pwm on generic
gpio LEDs for brightness control where none was possible before for
example.  Although I guess on realworld systems, that might still be a
bit flickery.

Otherwise I don't mind where it goes, I jumped in because I thought you
were trying to say "do it in userspace" ^^ and because there is some
subtlety about where to choose to put it to consider, even if LEDs is
the best place in the end.

-Andy


-- 
Andy Green | TI Landing Team Leader
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