Re: [PATCH 2/2] cpufreq: drivers: Remove unnecessary assignmentsof policy-> members

From: Sekhar Nori
Date: Mon Mar 25 2013 - 05:42:19 EST


On 3/25/2013 2:15 PM, Viresh Kumar wrote:
> On 25 March 2013 14:06, Sekhar Nori <nsekhar@xxxxxx> wrote:
>> There is a line in the code a little above the ones you deleted that
>> also sets these same variables. I guess you were relying on that line to
>> set policy->cur, but that also sets policy->{min, max} which can be
>> cleaned up.
>
> This code is rather confusing or wrong, this was the state of code before
> this patch:
>
> policy->cur = policy->min = policy->max = davinci_getspeed(0);
>
> if (freq_table) {
> result = cpufreq_frequency_table_cpuinfo(policy, freq_table);
> if (!result)
> cpufreq_frequency_table_get_attr(freq_table,
> policy->cpu);
> } else {
> policy->cpuinfo.min_freq = policy->min;
> policy->cpuinfo.max_freq = policy->max;
> }
>
> policy->min = policy->cpuinfo.min_freq;
> policy->max = policy->cpuinfo.max_freq;
> policy->cur = davinci_getspeed(0);
>
>
> The tricky part is if/else, where if don't return error if
> cpufreq_frequency_table_cpuinfo() fails. We want to set ->min[max]
> and cpuinfo.min[max] always. And i can see this code not doing that for some
> case even with my patch.
>
> Possible scenarios:
> 1. Valid freq_table: My patch + what you suggested is required.
> 2. Invalid freq_table: We never set cpuinfo.min[max] with or without my patch
> 3. No freq_table: Only my patch is required.
>
> If i do what you suggested then 2 and 3 would fail... If you want to
> return error
> in case cpufreq_frequency_table_cpuinfo(), then i can fix it properly.

So down in the cpufreq driver probe below, we bail out if freq_table is
not provided. So all this checking for freq_table in the code you pasted
above is superfluous. If you can clean that part up and add checking for
cpufreq_frequency_table_cpuinfo() as you proposed, I will be glad to
test it out ;)

Thanks,
Sekhar
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