[PATCH v3] PM / devfreq: Add possible_frequencies device attribute

On 07/16/2014 05:50 PM, MyungJoo Ham wrote:

On Wed, Jul 16, 2014 at 12:01 PM, Saravana Kannan [off-list ref] wrote:

quoted

Some devices use freq_table instead of OPP. For those devices, the
available_frequencies sysfs file shows up empty. So, add a
possible_frequencies attribute/syfs file that list all the possible
frequencies.

For devices that use OPP, the output of this file will match
available_frequencies. It may change in the future to show all OPP
frequencies -- even the disabled ones.

Signed-off-by: Saravana Kannan <redacted>

Hi,


Please add a documentation entry for this new ABI having a little justification and usage included.

Will do.

Plus, I am considering to move trans_stat along with this entry to somewhere such as .../stat/*
(you don't need to take care of this.)

Ok.

Besides, as OPP seems becoming the standard as imagined when devfreq development started,
soon, devfreq may require OPP unless the devfreq device has continuous frequencies.

I agree. Only one caveat with OPP is that if a device isn't using OPP to
do any voltage scaling, then it forces a voltage column with 0s. Also,
even if we make OPP mandatory, we'll still want trans_stats that
currently seem to depend on freq_table being populated. I was actually
planning on sending out more patches later that'll do a lot of stuff
automatically for devices with OPP. Like creating freq_table, etc.

-Saravana

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