On 08/05/2012 10:19 PM, Shawn Guo wrote:
> 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().
>
This won't work?:
of_property_for_each_u32(...) {
if (i & 0x1) {
volt = val;
ret = opp_add(dev, freq, volt);
if (ret)
...
} else
freq = val * 1000;
i++;
}
Rob
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