Re: [PATCH V5] PM / OPP: Pass opp_table to dev_pm_opp_put_regulator()

From: Stephen Boyd
Date: Wed Nov 30 2016 - 17:00:28 EST


On 11/30, Viresh Kumar wrote:
> From: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
>
> Joonyoung Shim reported an interesting problem on his ARM octa-core
> Odoroid-XU3 platform. During system suspend, dev_pm_opp_put_regulator()
> was failing for a struct device for which dev_pm_opp_set_regulator() is
> called earlier.
>
> This happened because an earlier call to
> dev_pm_opp_of_cpumask_remove_table() function (from cpufreq-dt.c file)
> removed all the entries from opp_table->dev_list apart from the last CPU
> device in the cpumask of CPUs sharing the OPP.
>
> But both dev_pm_opp_set_regulator() and dev_pm_opp_put_regulator()
> routines get CPU device for the first CPU in the cpumask. And so the OPP
> core failed to find the OPP table for the struct device.
>
> This patch attempts to fix this problem by returning a pointer to the
> opp_table from dev_pm_opp_set_regulator() and using that as the
> parameter to dev_pm_opp_put_regulator(). This ensures that the
> dev_pm_opp_put_regulator() doesn't fail to find the opp table.
>
> Note that similar design problem also exists with other
> dev_pm_opp_put_*() APIs, but those aren't used currently by anyone and
> so we don't need to update them for now.
>
> [Viresh]: Written commit log and tested on exynos 5250.
>
> Cc: # v4.4+ <stable@xxxxxxxxxxxxxxx>
> Reported-by: Joonyoung Shim <jy0922.shim@xxxxxxxxxxx>
> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
> Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> ---

You should have asked for my Signed-off-by instead of just adding
it. Here it is to make things explicit and recorded:

Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>

Thanks for putting everything together and simplifying the error
case.

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