Re: [PATCH v2] PM / devfreq: Use freq_table for available_frequencies

From: Saravana Kannan
Date: Mon May 05 2014 - 14:18:43 EST


On 04/29/2014 01:00 PM, Saravana Kannan wrote:
> On 04/27/2014 06:41 PM, MyungJoo Ham wrote:
>> You are hereby changing the semmantics of the original
>> available_frequencies node.
>>
>> When a frequency/voltage pair has been disabled (opp_disable), probably
>> by opp_disable(), the frequency is no more "available".
>> However, when the driver author supplied freq_table as well as OPP
>> in order to see the statistics, the node will behave differently.
>>
>> Please do not affect the current users as long as it does not give
>> additional benefit or fix a bug.
>
> I was actually trying to stick with the semantics as it was documented.
> The documentation for this file says it'll show frequencies that are not
> allowed by the current min/max settings either. To me, an OPP disable
> seems similar to some frequencies "disabled" by min/max settings.
>
> Giving preference to OPP is not a hard change to do, but it seems to go
> againsts the documented semantics.
>
> Thoughts?

I'll send out another patch like you wanted -- with OPP being given
preference over freq_table when listing frequencies.

But I would still like to hear your thoughts. As of today, there's no
clean way to get the complete list of available frequencies that would
give a consistent output irrespective of the temporary limits/conditions
imposed by thermal, current limiting, etc. The round about way is to cat
trans_stat and parse the frequencies from that.

That's why I was trying to give preference to freq_table.

Thanks,
Saravana

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