[PATCH v2 2/4] PM / OPP: Initialize OPP table from device tree
Shawn Guo
shawn.guo at linaro.org
Mon Aug 6 13:19:19 EST 2012
On Sun, Aug 05, 2012 at 09:50:32PM -0500, Rob Herring wrote:
> > +Properties:
> > +- operating-points: An array of 3-tuples items, and each item consists
>
> 3 tuples?
>
It's the case of v1, and I forgot updating it. Thanks for spotting it.
> > + of frequency and voltage like <freq-kHz vol-uV>.
> > + freq: clock frequency in kHz
> > + vol: voltage in microvolt
>
> Although maybe 3 fields would be good for a flags field? I'm concerned
> it's a pretty generic name and not very future proof. What about
> transition times? Not sure how you would represent that as it probably
> depends on which points you are changing between rather than a property
> of the opp.
>
This is a binding for OPP, which does not define transition times.
As for cpufreq, we only need to represent a possible maximum transition
latency. The driver will ask regulator subsystem for voltage latency,
while the clock latency is defined in DT.
> I think this whole function can be written more concisely. Just iterate
> over the property and avoid the intermediate array allocation.
>
I'm not sure about that, since directly iterating over the property
means we have to take care of all these sanity checks done in API
of_property_read_u32_array().
--
Regards,
Shawn
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