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SubjectRe: [PATCH V4 07/14] cpufreq: mediatek: Add .get function
On 26-04-22, 19:13, Rex-BC Chen wrote:
> We have a non-upstream driver which tries to get frequency by
> 'cpufreq_get'.

This is the right thing to do there.

> When we use that non-upstream driver, 'cpufreq_verify_current_freq'
> will be further invoked by 'cpufreq_get' and it would cause voltage
> pulse issue as I described previously.

I see this will eventually resolve to __cpufreq_driver_target(), which
should return without any frequency updates.

What do you mean by "voltage pulse" here? What actually happens which
you want to avoid.

> Therefore, we apply the solution in this series.

I won't call it a solution but a Bug as .get() is supposed to read
real freq of the hardware.

> Recently, we found that using 'cpufreq_generic_get' directly in our
> non-upstream driver can do the same thing without pulse issue.

That would be an abuse of the cpufreq_generic_get() API. It is ONLY
allowed to be used while setting .get callback in the driver.

--
viresh

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