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Subject: Re: [PATCH] cpufreq: dt: check the error returned by
 dev_pm_opp_of_cpumask_add_table
To:     Viresh Kumar <viresh.kumar@linaro.org>
Cc:     "Rafael J . Wysocki" <rjw@rjwysocki.net>, linux-pm@vger.kernel.org,
        linux-kernel@vger.kernel.org
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From:   "quanyang.wang" <quanyang.wang@windriver.com>
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Date:   Thu, 25 Mar 2021 13:36:52 +0800
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Hi Viresh,

On 3/25/21 1:24 PM, Viresh Kumar wrote:
> On 25-03-21, 13:15, quanyang.wang wrote:
>> Thank you for pointing it out.  Do you mean that even if
>> dev_pm_opp_of_cpumask_add_table returns
>>
>> an error, dev_pm_opp_get_opp_count may still return count > 0 because
>> someone may call dev_pm_opp_add
>>
>> to add OPP to cpu succcessfully at somewhere else?
> Yes.
>
> There are two ways we can add OPPs today:
>
> - Statically via device tree. This is what
>    dev_pm_opp_of_cpumask_add_table() tries to do.
>
> - Dynamically via call to dev_pm_opp_add(), which I described earlier.
>
> What failed here is the static way of adding OPPs, we still need to
> check if OPPs were added dynamically.

Thank you for shedding light on this.

I will send a V2 patch which only check the return error -EPROBE_DEFER.

Thanks,

Quanyang

>