Capture functionality dmtimer

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Hello Ladis, Keerthy,

I'm trying out your combined patches to move dmtimer to clocksource and
then activate the capture functionality.
However, I have an unfortunate issue, that is that the pwm-omap-dmtimer
driver gets loaded before the timer-dm clocksource driver. As such, the pwm
driver cannot access the platform data of the dmtimer, because it is not
yet filled in by the timer-dm driver.
I was wondering if you've had this issue also, and if so, how did you
resolve it?
I could defer the probe if pdata is NULL, but there is no way to know if
pdata is ever gonna be filled in. So I'm wondering how it worked on your
systems?

I looked at the working of the capture code and the TI datasheet, and I
fear you are correct that there is no way of knowing of you are sampling
the duty cycle or the inverse.
In a real-time system, you could configure the capture mode in singledetect
rising edge, reconfigure the capture mode in interrupt to falling edge, and
voila.
Another way would be to do a dual detection (as now), reconfigure the pin
during IRQ to GPIO and read out the value. This might be doable with the
ARM FIQ, but it is a hell of a workaround.

So using this for duty cycle detection will never work I think without
severe hacks.
However, I only need frequency determination, so for me, it is usable.

Thanks for your work and your input,
Brecht
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